Manual TitriSoft 2.6 / P

Manual TitriSoft 2.6 / P

1.1. Software Installation and Initial Start

1. Installation ..........................................................................................6 1.1. Software Installation and Initial Start................................................................ 6 1.2. Creating a Configuration for Checking the RS-Configuration........................... 7 2. General Proceeding .........................................................................10 2.1. Login 10 2.2. Concept Creation and Configuration Check....................................................13 2.3. Concept Creation for Methods ........................................................................13 2.4. Concept Creation for a Work List ....................................................................14 2.5. Concept Titration With Your Work List ............................................................15 3. Hardware Center..............................................................................17 3.1. Creating a Configuration .................................................................................18 3.2. Creating a New Configuration.........................................................................18 3.3. Creating an Additional Configuration ..............................................................20 3.4. Checking a Configuration................................................................................21 3.5. Add or Delete Devices ....................................................................................21 3.6. Compatibility List of Devices ...........................................................................23 3.7. Creation of Users............................................................................................24 3.8. User Concept With Authorizations ..................................................................26 3.9. Creation and Deletion of a User......................................................................27 3.10. Change User Level and Password..............................................................28 3.11. Tracing the RS-Configuration and the Method Procedure...........................29 3.12. Tracer Concept............................................................................................29 3.13. Turn Tracer on and off.................................................................................30 3.14. Work With Trace-Files in TitriSoft or on Operating System Levels..............30 4. Methods Center................................................................................32 4.1. Creation of Variables ......................................................................................32

4.1.1. Creation of Reagents................................................................................ 32 4.1.2. Creation of Results................................................................................... 33 4.1.3. Creation of Global Variables....................................................................... 34 4.1.4. Creation of Sample Data ........................................................................... 35

4.2. Creation of a Method ......................................................................................36 4.2.1. Changing a Method .................................................................................. 41 4.2.2. Modules of a Method ................................................................................ 42 4.2.3. Titration ................................................................................................. 43 4.2.4. Measuring Value...................................................................................... 49 4.2.5. Dosing................................................................................................... 51 4.2.6. Calculation ............................................................................................. 51 4.2.7. Repetitions ............................................................................................. 54 4.2.8. If-Statements .......................................................................................... 55 4.2.9. I/O-Connection ........................................................................................ 56 4.2.10. Command .............................................................................................. 57 4.2.11. Screen Message...................................................................................... 57 4.2.12. Stirring Speed ......................................................................................... 58 4.2.13. Reset Curves .......................................................................................... 59 4.2.14. Delay time .............................................................................................. 59 4.2.15. Input Box ............................................................................................... 60 4.2.16. Titration Types and Their Parameters........................................................... 61 4.2.17. General Method Adjustment ....................................................................... 65 4.2.18. Allocation Hardware ................................................................................. 67 4.2.19. Dynamic Control ...................................................................................... 68

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4.2.20. Drift Control ............................................................................................ 72 4.2.21. End Criteria ............................................................................................ 73 4.2.22. Dynamic Titration..................................................................................... 76 4.2.23. Linear Titration ........................................................................................ 77 4.2.24. End Point Titration ................................................................................... 79 4.2.25. pH-Stat Titration ...................................................................................... 81

4.3. Calculation of a Result ....................................................................................83 4.3.1. Creation and Editing of a Formula (Creation and Editing).................................. 83 4.3.2. Concept of the Variables in a Formula .......................................................... 86 4.3.3. Calculation of an EQ of a Potentiometric Curve .............................................. 89 4.3.4. Calculation of an EQ of a Conductivity Curve ................................................. 90 4.3.5. Calculation of an EQ of a Photometric Curve ................................................. 91 4.3.6. Creation of a Formula ............................................................................... 91 4.3.7. Calculation Average Value and Standard Deviation ......................................... 94 4.3.8. Calculation with Sample Variables and Input Variables..................................... 96 4.3.9. Calculation for ISE Calibration and Measurement ......................................... 100

4.4. Examples of Methods ...................................................................................104 4.4.1. Dynamic Acid-Base Titration Hydrochloric Acid/Sodium Hydroxide Solution........ 104 4.4.2. Dynamic Acid-Base Titration Phosphoric Acid / Sodium Hydroxide Solution........ 106 4.4.4. Acid/Base Capacity ................................................................................ 108 4.4.5. Chloride Titration ................................................................................... 113 4.4.6. Redoxtitration Titration with Thiosulfate....................................................... 115 4.4.8. TAN in Oil ............................................................................................ 118 4.4.10. Direct Measurement Fluoride and Calibration............................................... 121

5. Titrations Center.............................................................................127 5.1. Creation and Modification of a Work List ......................................................130

5.1.1. Creation of a Work List............................................................................ 130 5.1.2. Add and Delete Samples ......................................................................... 132 5.1.3. Delete Work Lists................................................................................... 133 5.1.4. Configuration of a Work List ..................................................................... 134 5.1.5. Configuration of Variables........................................................................ 137

5.2. Defining the Documentation..........................................................................140 5.2.1. Printout................................................................................................ 140 5.2.2. Export ................................................................................................. 143

5.3. Carry out Titration .........................................................................................145 5.3.1. Start and Stop Titration ........................................................................... 145 5.3.2. Work List during Titration ......................................................................... 147 5.3.3. Direct Operation with Titrator and Sample Changer ....................................... 147

6. Database........................................................................................151 6.1 Configuration File..........................................................................................153 6.2. Selection of a Sample ...................................................................................154

6.2.1. Sort and Select Samples ......................................................................... 155 6.2.2. Adjust Selection Criteria .......................................................................... 156 6.2.3. Detail Selection Criteria ........................................................................... 156

6.3. Export and Import .........................................................................................158 6.3.1. Text Information .................................................................................... 158 6.3.2. Pdf-Files .............................................................................................. 159 6.3.3. EXCEL ................................................................................................ 160

6.4. Information on a Sample...............................................................................161 6.4.1. Graphic................................................................................................ 161 6.4.2. Sample Information and Results................................................................ 162

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6.4.3. Data List .............................................................................................. 163 6.4.4. Method ................................................................................................ 164 6.4.5. Subsequent Calculation........................................................................... 164 6.4.6. Add a Calculation................................................................................... 166 6.4.7. Change of a Calculation .......................................................................... 166 6.4.8. Delete Samples, Reorganize Database....................................................... 167 6.4.9. Delete Samples ..................................................................................... 167 6.4.10. Downsize Database................................................................................ 168 6.4.11. Data Backup ......................................................................................... 168 6.4.12. Edit Database ....................................................................................... 168

7. FDA-Requirements ........................................................................170 7.1. Electronic Records........................................................................................170 7.2. Access Control..............................................................................................170 7.3. Copies of Electronic Records........................................................................174 7.4. „Audit Trail“ ...................................................................................................175 7.5. Electronical Signature ...................................................................................178

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TitriSoft 2.6 allows the titration with the following Schott titrators, burets and sample changers:

• TitroLine alpha plus • TitroLine alpha • TR 250 • T 110 plus • T 200 • T 110 • T Universal • T 97 • TW alpha plus • TW alpha • TW 280

Here, the titrations will be controlled by means of the software. Thereby, the input of measuring results of the titrators and burets will be used in the methods independent from each other. Thus, for one titration the input of the measuring inputs of one titrator is definable, whereas the titration reagent will be dosed out of another buret. In a row the hardware will be connected at a serial interface of the PC. The concept is named „Daisy Chain“. Here, the serial interface of the PC will be connected with the RS interface 1 of the first device (titrator, buret or sample changer), the RS-interface 2 of the first device with the RS-interface 1 of the second device. Every device needs another address. Due to the fact that there are up to 16 addresses, it is possible to connect up to 16 devices. Attention: TitroLine alpha must be the last device in such a row! Such a row of devices is called „Configuration“! For the cables and their respective designations please refer to the instruction manual or also the price list. TitriSoft 2.6 requires:

• 512 MB RAM • 800 MHz Processor • 20 GB Hard disk • WIN 2000, WIN XP (Prof.) • Graphic min 1024 * 768 • MS Internet Explorer 6.0 or later or installation of the MS Data Access Software (the driver can

be found in the TitriSoft directory) If any other software applications will be used simultaneously, it can be possible that more memory is required in particular cases.

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1. Installation In order to use the software, the following steps must be processed:

• Connect hardware with PC. • Install software. • Configure methods and work lists.

The connection of the hardware has already been described in the first part. The installation of the software will be carried out in the usual way, i.e. the way other common software applications will be installed.

1.1. Software Installation and Initial Start After the start of WINDOWS EXPLORER, the installation will be started by double-clicking with the left mouse button onto the data file “setup.exe” on the installation-CD. Subsequently, the installation routine guides you through various windows which must be confirmed for a successful installation. The different screens are:

Licensing agreement Last information on requirements or other notes User name and company name Installation directory and hard disk

We recommend to read this information carefully and to confirm them with all settings. Afterwards, the installations starts automatically into the specified directory: ”c:\Programme\Schott Instruments GmbH\TitriSoft 2.6” After the completed setup, the setup routine can be abandoned. It is not necessary to restart the software. Now, TitriSoft can be started via a symbol on the WINDOWS desktop or in “START”, PROGRAMME”, “TitriSoft 2.6”. With the first start it is necessary to select the directory for the TitriSoft data base. The location of the database can be freely chosen, i.e. it can also lie on the server.

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1.2. Creating a Configuration for Checking the RS-Configuration

Name and password will be asked for in a login-window. Already registered user names can be picked from a list. The login names will be saved in the data file “TitriSoft.ini” and can, if necessary, also be deleted. If the complete ini-file will be deleted, a new one will automatically be generated. Here, the location of the data base will again be queried.

For further information please refer to chapter 2.1 section „Login“. TitriSoft adjusts its appearance to the user. One user will be provided with the sample list in the titration center or additionally with the database, the experienced user will be provided with all functions, except the deletion and creation of users. But it is only the administrator who can use all functions without any restrictions.


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A new configuration will be created by selecting the menu item <Configuration> and, there, the menu item <New>. A pop-up window appears where many entries can be made. At first, the name will be entered, in this case “Check device connection“. Such a name will only be assigned for testing purposes. The name should refer to the type of the devices connected, such as “TL alpha + with TW alpha +” or the location, such as “Order laboratory“. In the next line the COM-Port (RS 232-Interface) will be selected from a row of available interfaces. On this interface the buret or the titrator must be connected. For the final configuration it is necessary to tick off the weighing machine if it has been connected as last device in a row.

After confirmation with <OK> it is now possible to select the newly created configuration on the left side of the screen. It is possible to click on the “+” sign in front of “Configurations“, it will change into a “-“ sign and a list of the created configurations will appear. If the newly created configuration is highlighted in blue, the connected titration hardware will be checked and displayed with the menu item <Hardware> and then with the menu item <Determine>.

The number of detected devices will be shown in a window and the devices will be listed with their respective characteristics. A check mark in the field <Device is on> means that this device was found with the current “Scan” procedure.

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In case no device has been found, possible reasons might be:

Wrong COM-interface selected. The interfaces in the PC or in the titration devices are not properly configured. The common transmission parameters are: 4800 bauds, 7 data-bits, no parity, no handshake. Wrong cable used. Opposite to a null modem cable the pins 2 and 3 are interchanged. Attention: A TW alpha plus can only be set up to 8 data bits. In practice, the second interface of

the previously connected TL alpha plus will be configured differently. The presetting of the TL alpha plus for the interfaces 1 and 2 are:

4800 Baud 7 Data bits 1 Stop bit No parity No handshake

If a TL alpha plus is connected, the interface 2 in the TL alpha plus will be changed into: 4800 Baud 8 Data bits 1 Stop bit No parity No handshake

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2.1. Login

2. General Proceeding In a first step the hardware will be connected to the PC and turned on. Subsequently, the configuration will be created, i.e. a collective name will be entered for all connected devices. After the right RS 232-interface has been selected, the hardware will automatically be determined. The number of all detected devices will be shown in a status notice and all devices will be listed with their respective characteristics. Only devices that have a check mark in the line “Device is on“, are available within this software. In the next step the methods will be generated. In these methods it is only possible to select these devices that have been found during a hardware scan. The method can contain a measuring value, a dosing task or a titration with calculation. The third step is the creation of a work list. A work list contains a chart that lists all samples and the associated methods with the associated adjustments. In the first instance, the desired number of samples will be copied and pasted into the work list. Moreover, for each sample the associated method will be selected from a list.

Create and determine configuration

Generate method(s)

Create and configure work lists

Start titrations. After the titration the samples will be saved in the database

During the titration an online graphic is being displayed. After the titration the results and curves will be stored in the data base.

2.1. Login If a user will newly be created or he or she logs in for the first time, he or she must enter his or her password. This password must comply with some specific conditions. These conditions will be determined by the system administrator and will be stored in an “Installation qualification” or SOP. Possible conditions might be:

Password length Numerical signs must be included Special signs must be included Validity period

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2.1. Login

If a password has been entered wrongly for the third time, the access will be blocked for the respective user. This user can only be reactivated by the administrator. The following user levels will be distinguished:

Routine user – can process and document analyses in work lists, can create and position work lists.

User – can, additionally, access the data base for the purpose of subsequent calculations or documentations.

Expert – can, additionally, create and change configurations, variables and methods. Can access all essential functions of TitriSoft.

Laboratory director – can, in addition to the expert, release samples and methods. Administrator – combines, additionally, the user and system administration. Can, under

specific conditions, delete methods or results. Accordingly, the users see only “their” respective functions. Screen for the routine user:

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2.1. Login

Screen for the user:

Screen for the expert and the laboratory director:

Additional functions for the administrator:

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2.2. Concept Creation and Configuration Check

2.2. Concept Creation and Configuration Check A configuration contains all specifications on titration devices that are demanded by TitriSoft. It is possible to create as many configurations as desired. Methods base on the devices that are contained within a configuration and can not access devices in any other configuration. Configurations will be generated in the hardware center. The minimum access level required is “user. The variables in TitriSoft, e.g. global variable, results and reagents, are available for all configurations. Chapter 1 describes the first check of the devices connected. If the devices „respond“, i.e. a check mark is on every device in the hardware-configuration, this means:

The device is ready and can be used in a method The device is properly connected The communication between titration devices and computer is alright

The name of a configuration should be assigned meaningfully. With many different configurations, this name could be the purpose or the compilation of the devices. The following name types will often be used for installations carried out by us:

List of connected devices, e.g. TL alpha plus with TW alpha plus Purpose of the work list: device test, routine analyses, methods check Laboratory names

2.3. Concept Creation for Methods A method describes the procedure of an analysis including all its parameters and calculations. Precondition is a configuration. It will be created in TitriSoft from components that contain variable and parameter. Normally, a method consists of a component “Titration” and at least a component “calculation“. In a method only these devices are available which are contained in the configuration. The devices must be set to “active“. Devices are active if they are switched on or if they have successfully been determined during the configuration check. In the first step of the method creation, the required variables, such as reagents and results, will be defined.

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2.4. Concept Creation for a Work List

In the next step the method will be given a name and the procedure will be composed of components.

Here, various components are available which can be used to adjust a method to all practical requirements.

All respective details are specified in chapter 4.

2.4. Concept Creation for a Work List In a work list the methods will be executed. The samples will be entered in a clearly arranged form and for each sample the respective method will be selected. In a work list it will also be defined, what such a sample list is supposed to look like. This refers to the representation on the screen as well as the representation during the documentation.

In this level a titration will be started and the online representation of the titration curve is visible.

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2.5. Concept Titration With Your Work List

A work list will newly be created, the samples will be entered and the characteristics will be defined. The characteristics are e.g.:

Type and look of the documentation Sample changer or single sample Data export Limits for weighted samples

2.5. Concept Titration With Your Work List In a sample list a sample will be entered. Thereto, a sample (e.g. with copy and paste) will newly be entered. The method will be chosen and the weight of the sample will be entered. It is certainly

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possible to take over the weighted sample automatically from a connected weighing machine. Every new sample has the status “Planned” until the sample list has been started.

Now, the sample can be titrated. Thus, the start symbol in the upper right corner must be clicked on.

The status changes from “active” and the online graphic can be displayed by displaying the configuration name above left in the “explorer” window.

After the titration has been finished, the result including the titration curve will be saved in the data base, the results will be shown in the sample list. The titration curves are visible in the titration center until the program has been shut down.

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3. Hardware Center In the hardware center the configuration of the titration software will be carried out. The following issues will be represented and configured:

Configurations with the connected hardware Users and their rights Backup of the data base Rule for passwords Audit trail for the FDA requirements System tracer for solving hardware problems.

The functions of the FDA version of TitriSoft (version 2.6 P) will be specified in the chapter with the FDA characteristics. As general adjustments the data backup of the complete data base as well as the compression of the data base are possible. The compression will be recommended if data have been deleted. The fields in the data base are indeed empty, but still occupy the space. This space will again be compressed by means of the function “Repair and compress“. The data base can, depending on the number of deleted entries, shrink to approx. 10% of its original size.

A successful compression will be displayed on the screen by means of the following message.

The data backup will be executed within time periods specified with the user settings. However, they can also be carried manually at all times. The successful backup will be displayed on the screen by means of the following message.

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3.1. Creating a Configuration

A copy with the name of the data base will be generated, for which date and time will be added. An mdb-file with the name of the data base, an ldb-file that shows that the data base is open and the data backup for which data and time had been added will then be existent in the Titrisoft directory.

3.1. Creating a Configuration The configuration is the summarizing organizational unit that contains all methods and the devices associated. All devices must have different addresses. At first, all devices must be connected and turned on. With the connection of the devices, errors could occur in a very few cases. In practice, the following failures could be observed:

Wrong cables (null modem cables are not suitable, since the arrangement of the pins 2 and 3 is different).

A RS-interface is not available under WINDOWS. The PC has only USB interfaces. In this case, appropriate adaptors are available. After they

have been installed, WINDOWS will show the interface. The interfaces on the devices have not been configured properly. The sample changer can

only process 8 data bits, whereas the standard setting of the most devices is 7 data bits. The devices have identical addresses, only the first device with this address will be detected.

For the analysis of this problems, the system tracer will help (described below in the text). It is possible to create as much configurations as desired. If it is necessary to operate several devices at the same time, for every single device a configuration will be created. For parallel operations, these configurations must be operated via different RS interfaces of the PC.

3.2. Creating a New Configuration After the installation, the first step in TitriSoft is the creation of a configuration. The configuration contains all device information TitriSoft needs for the titrations.

The name is an important organizational and arrangement criteria for the working routine and should, thus, be assigned with appropriate criteria. Additionally, it is necessary to select the COM-interface of the PC where the devices are connected. The program will show all PC interfaces available under WINDOWS. If a weighing machine will automatically be connected, this field will be marked in this window. However, this procedure can well be carried out later.

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3.2. Creating a New Configuration

Now, the connected devices can automatically be determined. For this, the devices must have been connected to the COM-interface and switched on. Please make sure that the first device is connected with its interface 1 to the computer, and the second device with its interface 1 to the interface 2 of the first device.

After the hardware scan, a message appears showing how many devices have been found. All devices will be listed and turned active. If no or just a part of an device has been detected, the following criteria must be checked:

Settings of the data transfer parameters of the devices Cabling and the RS interfaces selected Cable and plugs (original cables, corrosion, etc.) All devices turned on? All devices ready for communication?

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3.3. Creating an Additional Configuration

3.3. Creating an Additional Configuration An additional configuration will be created in the same way as the first one:

Enter name for new configuration Select RS-interface Activate weighing machine if directly connected Determine hardware

At first, “Configurations“ will be marked on the left side and, then, the menu items “Configuration“ and “New“ will be selected. A window appears with the designation “Record editor“. There, the name of the configuration will be entered. The name should be chosen according to the same criteria as recommended for the creation of the configuration. The interfaces available will be shown and the interface with the connected devices will be selected. If a weighing machine has been connected, the respective field will be marked.

Subsequently, the configuration will be determined and shown, according to the first configuration.

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3.4. Checking a Configuration

3.4. Checking a Configuration The configuration will be marked and the menu item “Hardware“ and “Scan“ will be selected. After a short while the number of connected devices will be shown in a window. During this process an hour glass appears. If this hour glass does not appear, TitriSoft can not address this serial interface. Then, the serial interface must be checked.

After the scanning procedure all found devices will be shown. All devices that have a check mark at “Device is on“, could have been detected. Since in the Daisy Chain Principle all devices are connected in a row, devices can not be detected after device which has been turned off or is defective.

3.5. Add or Delete Devices If new devices will be added to a configuration, these devices can be detected by means of a new scan, as described in Creating a New Configuration. Besides that, it is possible to add devices to a configuration even if they are not connected to the system. However, some characteristics will not be available.

The configuration will be marked and the menu item “Hardware“ and „New Device “ will be selected. Now, a window appears in which the device and the address can be selected.

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3.5. Add or Delete Devices

In case of a TL alpha plus no name will appear and the device will have no marking for the menu item “Device is on“. The parameters for the cap, the dosage speed, the filling speed are only pre-settings. The calibration values of the pH-electrodes have been set to “0“, since they are not (yet) existing.

It is possible to delete a device in a configuration. For this, it is necessary to firstly mark the line with the device name.

The device will be deleted from a configuration with the menu item “Hardware“ and “Delete Device“.

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3.6. Compatibility List of Devices

3.6. Compatibility List of Devices The devices can basically be rationed according to the properties dose and measuring. The dosage device has the characteristics: size top unit, dosage speed and filling speed, provided that these settings will be supported by the software. A titrator can measure and needs the calibrating values slope and zero Point for the pH-values. The measuring unit will be shown accordingly. Sample changers TW xxx will be configured in the Titrations-Center and have the characteristics:

Plate size Flushing position Connection to a slush pump Waiting position (Position for the electrodes after the titration)

The following chart shows the devices available and their respective characteristics. Device Dose Measure pH Calibration TL alpha plus 1, 5, 10, 20, 50 ml

Dosage speed Filling speed

Measuring inputs A and B pH, mV, µA, oC, s

At Titrator

TL alpha 10, 20, 50 ml Dosage speed Filling speed

Measuring input A pH, mV, µA, oC, s

At Titrator

TR 250 - Measuring inputs A and B pH, mV, µA, oC, s, %T,

mS

In Titrations-Center from TitriSoft

T 110 plus 1, 5, 10, 20, 50 ml Dosage speed Filling speed

- -

T 200 1, 5, 10, 20, 50 ml Dosage speed Filling speed

- -

T 110 1, 5, 10, 20, 50 ml Dosage speed Filling speed

- -

T Universal 20, 50 ml Dosage speed

- -

T 97 20, 50 ml Dosage speed

- -

TW alpha plus - - -

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3.7. Creation of Users

TW alpha - - - TW 280 - - -

3.7. Creation of Users The menu item for the configuration is only available for users with the access level “Administrator“. Other users can not see this menu item.

The users have the following characteristics:

User access or user type Access name Complete name Function Active or inactive Password

Passwords will not be shown. The sorting (even manifold) is easily possible by marking the title line with the mouse and successively pulling it upwards by means of the mouse.

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3.7. Creation of Users

A sorting according to particular fields is also possible by clicking on the title. A new user will be created via the menu item “Users“ and “New“.

The user type will be selected from list, the function chosen or entered. The name is the log-in name, which will be substituted in the documentation by the complete name. The user will be turned active and, if necessary, provided with a password. This password must be substituted at the first log-in. If no password will be provided, it is not necessary to enter a password in the log-in window.

A list of users can, even sorted according to certain criteria, be printed or saved as PDF-file.

The printout is predefined and can only be adapted by the sorting criteria and the sorting of the columns. The PDF-version will be created automatically with the predefined name into a predefined directory. The list of users “Users” in the directory “Userlist“, the individual user under “Others“.

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3.8. User Concept With Authorizations

3.8. User Concept With Authorizations The following user types will be differentiated:

Routine user – Can process and document analyses in work lists, can create and set work lists.

User – can additionally access the database for the purpose of subsequent calculations or documentation.

Expert – can additionally create and modify configurations, variables and methods. Can access all essential functions of TitriSoft

Laboratory director – can, additionally to the expert, release samples and methods Administrator – includes additionally the user and system administration, can, under certain

circumstances, delete methods and results Both types, routine user and user, can process titrations and can organize the work in the titrations-center. Thus, they can create work lists, can configure sample lists and can document them at every time. Graphics are only available until the software will be shut down. Subsequently; the graphic is only visible in the data base. Users can additionally work with the database. There, it is also possible to carry out subsequent calculations and to create further documentations. Basically, the expert can use all functions of the software, except for releases and the administrator functions. The administrator functions are:

User administration All delete functions

Delete functions are automatically connected with a complete copy of the entire database. The requirements for the password can be determined by the administrator globally for all users:

Interval for password changes in days (the new password will automatically be asked for after this interval) Minimal length of the password in characters, numbers or letters A marking at “Numeric char required“ means that at least one number is required in the

password A marking at “Special char required” means that at least one special char is required besides

the letters and numbers in the password. The settings for the reminder of the database saving will here be carried out by the administrator. The interval refers to days. The settings are put in this place, since only the administrator has access here.

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3.9. Creation and Deletion of a User

3.9. Creation and Deletion of a User User will be created as described in chapter 3.7. User can only be deleted as long as no data sets are connected with them. As soon as a user creates methods or has generated analyses results, a user cannot be deleted anymore. According to every deletion process, it is necessary to enter one further person. Since only administrators are authorized to access the user administration, it goes without saying that this person must have administrator rights. The deletion process is carried out via the menu “Users” “Delete“. The confirmation of one further person with authorization is necessary.

A confirmation message prevents accidental deletions.

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3.10. Change User Level and Password

As soon as “Electronic Records” of the user are existent in the data base, it is not possible anymore to carry out a deletion!

3.10. Change User Level and Password Changes of authorization levels, complete names and of the task in the laboratory can always be carried out by the function editing. Here, an input in the audit trail will be generated in the FDA-version.

Accordingly, the activation or deactivation is also possible.

A password can be carried out by the respective menu item or by marking or deleting the < password or the user. If a user has no password, he or she can create a new password at the start of the software and, thus, does not need to enter an old password.

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3.11. Tracing the RS-Configuration and the Method Procedure

3.11. Tracing the RS-Configuration and the Method Procedure In TitriSoft the error messages and the starting of methods and work lists will continuously be saved in a trace-file. If the system tracer is marked on the left side in the explorer window, in the middle appears a list of the data saved. These data files will clearly be marked with the date in the name of the data file. If the software will be started for multiple times a day, the new information will be added.

In order to prevent that the data files become too large in the routine, it is possible to adjust two steps:

Standard: The start and the quitting of methods and work lists will be entered as well as error messages Trace all: Additionally, the serial communication from of PC and titration devices will be

traced. Everything will be recorded if “Trace all” is marked with a check mark.

3.12. Tracer Concept For the most part, the tracer is used for documenting problems of all kinds and, therefore, to detect their causes easily and fast. The resulting data files will be saved as pure text files, in order to avoid that special tools are necessary for the process. Since all electronical inputs will be saved automatically in the database and all changes will also be saved in Audit Trail (FDA Version), there are no rules and norms for recording the information in the so-called log-file. The columns, time, user and “Source“, and a comment will be saved. With the documentation of the RS communication the commands from the PC to the devices and also the information of the devices to the PC will be saved. The following lines show that TitriSoft asks for the devices connected with the command RH on the address 01 and 03. In each case, a TL alpha plus with the address 1 and a sample changer on address 3 will respond with their identity: 10 1 12 9 5 'Snd: 01RH '

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3.13. Turn Tracer on and off

10 1 13 9 5 'Rcv: 01Ident:Tl_Alpha plus' 10 1 12 9 5 'Snd: 03RH ' 10 1 13 9 5 'Rcv: 03Ident: TW280' The responds can come with delays and will be brought into the appropriate reference to each other by TitriSoft.

3.13. Turn Tracer on and off Basically, the tracer can not be turned off. However, large data files will only be generated if the RS communication will also be saved. This can be shifted via mouse markings of the respective menu item. If there is a check mark, the RS communication will be saved also. Then it is possible that files will be created with a size of more than one megabyte per day.

3.14. Work With Trace-Files in TitriSoft or on Operating System Levels As indicated in chapter 3.11, the content of every trace-file can be shown. It is also possible to sort according to different criteria by marking the respective headline with the mouse.

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3.14. Work With Trace-Files in TitriSoft or on Operating System Levels

However, the usual way to deal with the trace-file will be on WINDOWS-level: The file will be loaded with WINDOWS EDITOR or WINWORD and, then, analyzed. In case of problems, it is also possible to send these files via mail to the customer service of Schott Instruments. It is recommended to compress the files with an appropriate program. The rate of compression is very high, very small files will be created which can thus be send via mail in a very fast way. The files, including the date in the file name, are located in the directory: \Programme\Schott Instruments GmbH\TitriSoft 2.6\Log

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4.1. Creation of Variables 4.1.1. Creation of Reagents

4. Methods Center In the methods center the methods will be created after a configuration has been created. However, it is not possible to finalize the creation of a method without having the devices defined in a configuration.

In the left part of the screen the configurations with the methods are visible. Every configuration is marked with a small PC symbol. In front of the symbol there is a + or – sign. By clicking onto the + sign the methods of the configuration will be shown. Below the configuration are the methods and the variables of the system:

Results (designations for results) Chemicals (reagents with name, titer, and time of determination) Globals (global variables, with which the results within a method or between methods can be

transferred) Sample data (user defined variables, which can be entered into the sample list and which can

be used for the calculations) Electrodes (calibrating coefficients of ionic sensitive electrodes will be saved here)

The methods are listed on the left side. On the right larger side the methods including additional information are listed:

Name Status Last change Name of method creator

4.1. Creation of Variables Variables can be created prior to creating a method or also during the method creation. They can be included in multiple methods. The variables Chemicals, Globals, Sample Data and Electrodes are global and can be used in all methods, their numerical values can be applied to all methods in the same way. With Results it is the names that can be applied to all methods, however, the numerical values are only defined in the current method.

4.1.1. Creation of Reagents

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4.1. Creation of Variables 4.1.2. Creation of Results

Reagents will be created by clicking onto “Chemicals“ on the left side. By means of the menu “Items“ a new reagent will be created with “New“. The name should include the reagent and the concentration. Basically, the name can be freely selected. The longer the name is, the clearer the reagent is identified. Due to the fact that the names of the reagents are listed in the titles of some charts, they could thus become quite confusing.

The characteristics of reagents are:

Value of the titer Maximum value, in case of exceeding this value will be color-coded Minimum value, in case of shortfall this value will be color-coded Date, when lastly determined

The designation of the (reagents?) can also be entered during the creation of methods. Reagents (Chemicals) will mostly be used in multiple methods and are global variables.

4.1.2. Creation of Results Results will be created by clicking onto “Results“ on the left side. By means of the menu “Items“ a new reagent will be created with “New“. The name should include a conceptual name. Basically, the name can be freely selected. The longer the name is, the clearer the reagent is identified. Due to the fact that the names of the results are listed in the titles of some charts, they could thus become quite confusing.

The characteristics of the reagents are:

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4.1. Creation of Variables 4.1.3. Creation of Global Variables

Name of the results Maximum value, in case of exceeding this value will be color-coded Minimum value, in case of shortfall this value will be color-coded

The names will be entered together with the unit. Examples are: OH-number mg KOH / g Water content in % Equivalence quantity (EQ) in ml It is only possible to document these results which have been defined as “Results“. If no equivalence quantity is defined as “Result“, this quantity will not be existent as result in the documentation. The results can also be defined in the formula editor. Here, also other characteristics will be determined, e.g. the number of decimal places.

The designation of the (results?) can also be entered during the creation of methods. The names of the results will mostly be used in multiple methods, however, the calculated numerical values are only known in the current method.

4.1.3. Creation of Global Variables Global variables will be created by clicking onto “Globals“ on the left side. By means of the menu ”Items“ a new reagent will be created with “New“. The name should include a conceptual name. Basically, the name can be freely selected. The longer the name is, the clearer the reagent is identified. Due to the fact that the names of the global variables are listed in the titles of some charts, they could thus become quite confusing.

The characteristics of the reagents are:

Name of the global value Pre-allocated value Maximum value, in case of exceeding this value will be color-coded Minimum value, in case of shortfall this value will be color-coded

The names will be entered together with the unit. Examples are:

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4.1. Creation of Variables 4.1.4. Creation of Sample Data

Blank value in ml Nominator Molecular weight in g

4.1.4. Creation of Sample Data Sample data will be created by clicking onto “Sample Data“ on the left side. By means of the menu “Items“ a new reagent will be created with “New“. The name should include a conceptual name. Basically, the name can be freely selected. The longer the name is, the clearer the reagent is identified. Due to the fact that the names of the sample date are listed in the titles of some charts, they could thus become quite confusing.

The special feature of sample data is the possibility to be able to enter the numerical value ion the titrations-center individually for every sample.

In order to add sample data in the titration-center, within the work list the item „Properties“ will be chosen and under the menu item “Properties “ a sample data will be added.

The sample property “Density“ can be named with a another title, which appears in the chart on the screen or in the printout. It will be marked whether the variable should be included on the screen, in the printout or even with the export in the chart.

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4.2. Creation of a Method 4.1.4. Creation of Sample Data

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The properties of the reagents are:

Name of the sample data Pre-allocated value Maximum value, in case of exceeding this value will be color-coded Minimum value, in case of shortfall this value will be color-coded

4.2. Creation of a Method The methods consist of individual modules. The most important modules are the titration-module and the calculation formulas. Normally, a titration method consists of a titration-module and one or multiple formulas. In order to adapt a method to particular requirements, a method can also be assembled from multiple modules. Multiple titration-modules add the generated data values to the global field of the titration curve. Equally modules with measuring values and dosages. If it is not wanted to have the data values in the titration curve up to a certain point, a reset of the data can be inserted at this point. Then, the titration curve starts at this point.


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At first, an existent method will be selected on the left side, this method can be modified in the next step. In order to create a new method, the configuration will be marked on the left side. Under the menu item “Analysis “ “New“ will be selected.

The name of the method can be entered in any form. The name should represent what will be done with the method. A name which is too long diminishes the clearness.

Now, under the index card “Analysis Info“ on the right side everything will be summarized, what will be available as information besides the method procedure. This is general organizational information, comments, variables and the electronical signature. Information for the “Electronic Signature“ are located in the description for the FDA-Information.


By clicking the double arrows in the titles it is possible to show only the titles or also the associated contents.

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The analysis flow will be shown under the tab “Analysis Flow“. All modules of the analysis and associated comments will be shown.

Under “Analysis Info“ a method can be checked technically and can, subsequently, be released. Further advises for this procedure you will find in the FDA Part of the description. It is possible to print an analysis. The printout contains general information, the flow and all parameters.

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In the same form a PDF-file can be generated in the same layout. The PDF-file will automatically be provided with a name and created in the subdirectory: ……\TitriSoft 2.6\Pdf The file name will be composed of the name of the analysis and the date.

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4.2. Creation of a Method 4.2.1. Changing a Method

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Under analysis flow the modules of a method will be shown which make up the analysis flow. The following menus are available:

Edit Modify, delete or insert modules Operation Insert modules for the analysis flow, add e.g. measuring data Utils Auxiliary functions, such as delay times, notes or special commands

The modules are shown in the following figure and will be described in subsequent chapters.

4.2.1. Changing a Method A method can be edited as long as it has not been checked or released. The changes can be both changes of parameters and changes in the flow of inserting or deleting modules. Changes are possible if the registration card “Analysis Flow“ has been selected.

If parameter have been changed, a disc symbol appears on the right side. Parameters will only be saved if they are saved here. Analyses that have not been saved will be marked on the explorer page with a starlet in front of the name. Multiple analyses can have the status “not saved“. This status will be retained until an analysis has been saved or until the software has been shut down. Changes which have not been saved will then be lost.

4.2. Creation of a Method 4.2.2. Modules of a Method

In the insert mode a module can be inserted in front of a marked module. In the following example the module “Titration“ is marked and in the insert mode the module “Measurement“ will be inserted in front of the module “Measurement“.

Marked modules can be deleted or edited. If it is not worked in the insert mode, the module can be inserted directly behind a marked module.

4.2.2. Modules of a Method Modules are available which can be used to implement the usual titration and measurement methods of the potentiometry.

The following chart presents modules and their properties: Modules Properties Titration The most basic module of a method. It contains all parameters of a titration.

In order to be able document a result of this titration, at least one formula is necessary.

Measurement This module contains a measuring value. Such a measuring value can only be documented, if it is listed via a result variable in a formula as final value.

Calculation Results and measurement values can be calculated and documented by means of calculation formulas.

Dose Buret With this module it is possible to dose (even calculated) volumes. Thus, a volume can be calculated from a weighed sample and can be dosed variably.

Repeat With this module it is possible to carry out processes in a method procedure

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4.2. Creation of a Method 4.2.3. Titration

as often as desired or even with a variable quantity of repetitions. If-statement With an If-statement a module in a procedure can be determined by

particular conditions. Titrator Method With the TL alpha plus the Karl Fischer Titration will be carried out with the

titrator. The results will then be transferred via a TAL (TitroLine Alpha) Mode into the TitriSoft database.

Calibration This module carries out a calibration with an ISE (ionic sensitive electrode). An equalizing calculation with as many calibration standards as desired will be calculated and the coefficients will be saved up to a function of the third degree (depending on the number of calibration points).

ISE Measurement By means of this module a measurement with a ionic sensitive electrode will be carried out which uses the coefficients of the function from the „Calibration“ as a basis.

Standard Addition With the Standard Addition it is possible to carry out a more matrix-independent determination of an ion on the basis of the calibration values of an ISE electrode or with a multiple standard addition through Gran-extrapolation.

IO Box With this module it is possible to control the I/O ports of the sample changer or the buret.

Delay Time With this it is possible to enter a defined delay time within an analysis flow. Stirring Time The stirring speed of the sample changer or on the devices with comparable

functionalities can be adjusted. Message Box A message on the screen which must be confirmed. Clear Curve With multiple dosage and titration modules all volumes will be added and

coherently be shown in the graphics. With this command it is possible to define that the curve starts at this point anew.

Direct command With this command it is possible to send direct commands to the titration devices.

Input Box With this input box it is possible to enter these values within a flow that are also necessary in a calculation, but are not yet available prior to the beginning of the titration.

4.2.3. Titration A titration will be defined with the module “Titration“. Basically, a method can be assembled by the modules “Measuring Value“ and “Dose“. These modules in connection with an “If“-statement can generate the values for a titration curve. However, it is more comfortable and better to use a titration-module. There, the following titration possibilities have been included:

Dynamic titration, with which most titrations can be titrated very precisely and fast. Endpoint titrations for conventional methods resulting in comparable results. Linear titrations for applications in organic solvents or other particular conditions. pH-Stat-titrations, in order to precisely comply with a pH-value.

Normally, the “Titration“ is the first module in a method. Depending on the application, the different conditions of the method will be adjusted one after the other. At first, the register card “Analysis Flow“ will be clicked with the mouse. Then, the module „Titration loop“ will be chosen from the menu “Operation “.

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Parameters will be configured for:

Titration Buret settings Settings for titration Settings screen

The parameters for the titration contains the selection of the titrator with its measuring input, the type of titration and the stirring speed. The buret adjustments contain respectively the selection of the buret, of the reagent and the time when the buret is to be filled. The actual titration parameters under the adjsutments for the titration are the criteria for the end of titration, the control of the step-length of the titration steps and the duration of titration via titration speed. Additionally, it is possible to adjust which value should be represented on which axis.

With the selection of the titrator the model, its address and all its measuring possibilities will be shown. The example “TL Alpha plus-1-pHA“ means that with the address “01“ a TL alpha plus is connected

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and the measuring input A has been selected for the pH-measurement. Always, the measuring possibilities of all connected titrators will be shown.

For example, a TL alpha plus has two measuring inputs A and B, on which, in each case, pH or mV can be measured. Moreover, it is possible to measure µA with connected polarization voltage. A connection for a Pt 1000 is available, with which the temperature can be measured. Basically, the time as “Measurement category“ can be used for all titrators.

The following titration types for the control of the step-length are available as finished working methods:

Dynamic titration, for which the step-length will be controlled in dependence on the slope of the titration curve. This means small steps in steep curve sections and large steps in flat ones. Linear titration means equidistant step-length in the course of the entire titration. Endpoint-titration is a fast titration on a preset endpoint, e.g. a particular pH-value. pH-Stat is a titration, in which a defined pH-value will constantly be adhered to by means of a

reagent-addition.

The stirring speed refers to devices that support this function: Sample changer and TL alpha. TL alpha plus does not support this function. The stirring speed can be adjusted in ten steps from 0 to 10. Standard setting is step 6, it applies to a medium-sized magnetic stirring staff in a 150 ml tumbler.

The reagent addition will be defined under the buret settings. This includes the selection of the buret from the connected burets and titrators, the selection of the reagent and the time for filling the buret. The latter issue will be used if a titration is composed of multiple modules and will not be filled between the individual modules. At the end of a titration or of a dosing procedure it is advised to refill, in order to be able to put on an interchangeable unit.

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A buret to be selected will be shown with name and address. It is advisable to mark directly at the device. Certain burets are compatible and will not be differentiated:

T 200, T 110 und T 110 plus T Universal, T 97

The reagent will also be selected from a list. The significance of selecting the appropriate reagent is if its titer is available in the formula editor as calculating variable.

If a method starts, all burets will be filled automatically. It might be important to use multiple titration modules in one method. If many modules will be used for optimization purposes, it is advisable not to fill between the modules. Since this would mean a loss of time and can lead to small steps in the titration curve (primarily with fast titration). Additionally, the filling process takes minimum 15 seconds due to the valve switching.

The settings of the titration parameters depend on the mode of titration. The following values will be adjusted:

End value of the titration and the value of the end point or the potential-value at which the titration is to stop. Control of the step-length in dependence of the slope of the titration curve. Titration speed in consideration of the setting behavior of the electrode.

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The numerical values for the end value and the end volume will not be entered directly, but via the formula editor. Its advantage is that the values van be calculated. For example, a pH-value can be measured at the beginning of a method and can, after multiple sample preparation steps, again be titrated to the same pH-value.

One further application is to calculate the end volume in dependence of the start measuring value, for the purpose not to use too much reagents.

While clicking on this line with the mouse three dots appear at the end of the line. If these dots have been clicked on, the formula editor appears. Then, the numerical value or a formula can be entered in this field. All these variables are available which are known to the method at this point in time in the method flow. A detailed description can be found in the description of the formula editor.

The number of equivalence points (EQs) refers exclusively to the stop criterion during the titration. Normally, it is one equivalence point. Two EQs show e.g. the titration curves of the water hardness with the calcium sensitive electrode and the phosphoric acid. Even if no value is entered here, it is possible to calculate one or more EQs in one formula. The EQ sensitivity will be determined by means of the curve shape. It bases on the value of the first derivative and can even be entered as a numerical value at the user settings for the curve shape.

With the curve shape the following issues will be controlled:

Intensity criterion for one equivalence point which is to end a titration. Check of the titration direction, falling or rising. The dynamic parameters that regulate the titration. Regulating parameter for a steep titration

curve mean a careful titration, in which the step-length will be reduced in time, in order to guarantee that there are small addition steps in the steep section. If a flat titration curve will be titrated with the parameters for a steep curve, too many small steps will be titrated and

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the titration has too many data points, takes too long and will be very noisy. If, conversely, a steep titration curve will be titrated with the parameters for a flat curve, this will lead to an over-titration.

The control of the step-length of a titration via the curve shape largely influences the titration speed. One further important factor is the time which is given to the electrode to obtain a stable measuring value. It will be adjusted via the parameter Titration Speed. Depending on the speed adjusted, the measuring value will firstly be transferred into the titration curve when a defined value has been exceeded. The drift will be used mV / Minute. The speed rates mean:

Turbo: Measuring value will be transferred without drift control Fast: The drift is 30 mV/min, a normal titration is approx. 3 min Normal: The drift is 10 mV/min, the titration takes approx. 5 min Secure: The drift is 5 mV/min, the titration takes approx. 10 min Custom: The drift will be adjusted by the user.

Additionally, the actual titration time depends on the step-length and the adjusting speed of the electrode. If a titration takes significantly longer than usual, in most cases it is the electrode that is the reason. Then, it should be regenerated or exchanged.

The titration speed can be adjusted by means of the following four parameter.

Parameter Unit Meaning Measuring interval

s For this time interval the criterion Delta will be checked. The value can reasonably be adjusted from 0,5 to 30 seconds. A common value is from 1 to 2 seconds

Delta mV/min Drift criterion, if this value in mV/min will be fallen short of during the measuring interval, the measuring value is alright. A common value is 5 mV/s.

Min time s The minimum time in seconds for a measuring value. A common value is 1 or 2 seconds.

Max time s The maximum time in seconds for a measuring value. A common value is 5 – 10 seconds.

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4.2. Creation of a Method 4.2.4. Measuring Value

During the titration the titration curve will be represented as online curve. The settings for the allocation of the axes will be carried out in dependence on the type of application. It is possible to choose the units for the x-axis and for two y-axes. Typical representations are:

Type of Titration x-Axis y-Axis 1 y-Axis 2 Acid-Base Titration Consumption in

ml pH- Value Optional Time in s

Redox Titration Consumption in ml

mV- Values Optional Time in s

Chloride Titration Consumption in ml

mV- Values Optional Time in s

Karl Fischer Titration Time in s Consumption in ml Optional Current in µA

pH-Stat-Titration Time in s Consumption in ml Optional pH-Value This setting will be saved and can also be used in the data base.

The settings will be taken over if “OK“ is pressed. However, a method can contain multiple modules and will only be saved if the disk symbol will be clicked on with the mouse in the upper right part of the screen.

4.2.4. Measuring Value The measuring value will be selected from the modules list under “Operation“. It can stand at any position of a method. If a measuring value will be recorded during a analysis flow, e.g. prior to a titration, it will be taken for the entire attempt. A measuring value pH recorded at the beginning would continuously be recorded during an mV-titration.

A measuring value is allocated to a titrator and its measuring input (A or B). It is possible to record measuring values of multiple units at the same time. The criteria for the stability or drift of measuring values can be parameterized as know from the titration. Here, the drift will be shown in mV / minute. The values mean:

Turbo: The measuring value will promptly be taken over without drift control

Fast: The drift is 30 mV/min, a usual titration approx. 3 min Normal: The drift is 10 mV/min, the titration takes approx. 5 min

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4.2. Creation of a Method 4.2.4. Measuring Value

Secure: The drift is 5 mV/min, the titration takes approx. 10 min custom: The drift will be adjusted by the user.

The measuring speed can be adjusted by means of the following four parameters.

Parameter Unit Meaning Measuring Interval

s For this time interval the criterion Delta will be checked. The value can reasonably be adjusted from 0,5 to 30 seconds. A common value is from 1 to 2 seconds

Delta mV/min Drift criterion, if this value in mV/min will be fallen short of during the measuring interval, the measuring value is alright.

Min Time s The minimum time in seconds for a measuring value Max Time s The maximum time in seconds for a measuring value

Recorded measuring values can be documented in the measuring and titration data or via a formula. In this formula a name will be entered for the measuring value, e.g. “Measuring value in pH“, the number of places will be named and the end value will be selected among the values.

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4.2. Creation of a Method 4.2.5. Dosing

Then, the end value pH can be represented in a work list in the chart. With the curve list or with individual documentations it will always automatically be transferred into the documentation.

4.2.5. Dosing By means of “Dose buret “ any desired volume can be dosed in any desired buret in a configuration. In a method dosing and titration volume can be used as desired. All volumes will be shown in a titration graphic and added if, at the same time, measuring values will be recorded. In order to reset the graphic to 0 after a dosage, a module “Reset curve“ must be used. The dosing volume will be entered into a formula, thus a volume value can be a calculated term.

4.2.6. Calculation In TitriSoft the built-in formula editor will also be used on many occasions to enter numerical values. Thus, it is possible to use variables or calculated terms instead of pure numerical values. For this there are numerous examples. Here, we mention only two of them:

A dosing volume will be calculated because of a weighted sample in order to adjust a defined concentration. The weighted sample can thus vary in a broad spectrum. A pH-value will be saved as measured. After some additions it will again be titrated onto this

pH-value, without the necessity of knowing this value previously. Basically, the formula editor will also be used to document results or intermediary results. All calculated values can be represented in the titration-center on the screen or in the printout in a chart. A formula can be integrated as module in the analysis flow at any desired place. The number of formulas is not limited. The selection will be carried out under the menu item “Operation“ and “Calculation“.

The following information will be shown and can (except for the type of variables) be entered:

Type of variables to be calculated or to be entered

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4.2. Creation of a Method 4.2.6. Calculation

Variables names Number of decimal places Number of equivalence points necessary in the formula. The formula itself Smoothing degree Analysis window for x-axis Analysis window for y-axis

If the formula editor is used, in order to enter a number, this number can directly be entered in the White Field. If signs are to be deleted, this can be done with the “Backspace button“ “ “, after the cursor has been positioned behind the last sign.

This example shows a formula for the calculation of the Chloride Content in %. The following items mean:

EQ[1] An equivalence point has been selected, in case of many – the first. 35,45 Atomic weight of chlorine 0,1 Molarity of the silver nitrate solvent, of the titration reagent. Titer[] Titer of the silver nitrate solvent 100 Ratio in % / Fraction stroke Amount Sample amount 1000 Ratio of g towards mg () The brackets

The usual mathematical calculation rules apply. Thus, the, for instance, the omission of brackets would mean that the expression will previously be divided by the sample amount and the obtained value will be multiplied by 1000 resulting in another outcome. The values within a formula can be entered “Manually“ or selected from the menus. Usually, it is advisable to enter the numerical values manually and to choose the variables from the menus.

If a new formula will be created for a result, in the first step a name has to be entered in the second line. If a name will be chosen from the second line, there is an automatic allocation to the variable type. The types of variables are described in chapter 4.1. Thus, results can be directly and promptly

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4.2. Creation of a Method 4.2.6. Calculation

entered as type while variables must be defined previously. Variable names can also be used for results in multiple methods since the values are only be known in the current method. Under the menu item “Values“ the variables can be chosen: Designation Meaning Explanation

Weighed Sample

Also „amount“ Every form of the sample amount, be it sample volume or weighed sample. The value can be entered in the titration – center for every sample.

End Volume End volume of all reagents, if it was titrated with two reagents, volumina will added.

Globals Global Variable Global variables will be used to exchange values between methods. Such as blank values, nominator or other.

Sample Data Sample Variable Sample variables behave like global variables but can, additionally, be entered as values into the sample lists in the titration –center, e.g. sample-specific density.

End Values End value The last measuring values of a measurement or titration. If many measuring values have been recorded in a method, there are also end values available.

Volume Chemicals

End Volume Reagent

Here, the end volumina of all reagents used in a method are available,

Titers Titer The titer of the reagents. It behaves like the global variables, but as additional characteristic it contains the date of the last determination.

Results Result Result variables are only known with their numeric values in the current method.

Averages Average Value The average value of a variable used in a method. Typical use is the calculation of the average value of a titer use. Thus, a result “Individual Titer“ will be calculated, then the variable Titer will be stored as Average of this result.

Standard deviation

Standard Deviation Calculation of the standard deviation as basic population according to the formula:

From the calculations different forms of the equivalence point calculations can be selected:

EQ There are as much EQs available as previously selected

These will be represented as EQn. It is possible to calculate up to 5 EQs. Attention: If analysis windows will be used, there is mostly only one EQ inside

this window!! A EQ will be calculated as maximum of the first derivative.

LF Analysis of conductometric or conductivity curves. The inflection point will be determined by means of the second derivative and, then, straight lines will be calculated from the starting point up to the inflection point and from the end point to the inflection point by means of linear regression. The point of intersection of the straight line is the EQ for LF-curves.

%T (1) Analysis for photometric titrations with phototrodes. It is likewise possible to use the normal EQ-calculation. With the calculation of the special photometric analysis, by means of the steepest section a straight line will be calculated. By means of the flat sections straight lines will likewise be calculated. The point of intersection of the starting straight line with the straight line through the steepest section is %T (1).

%T (2) The point of intersection of the starting straight line with the straight line through the steep section is %T (1).

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4.2. Creation of a Method 4.2.7. Repetitions

In the functions there are brackets available. Three levels are possible. Additionally, as functions are available:

Sqrt Root of a numerical value or even of composed numerical values Ln Natural logarithm Exp Exponential function e to the power of the numerical value or term X at Y Calculates the x-value on a given or calculated place, e.g. the consumption

with determined pH-value. In “Operators“ all common operations such as +, -, *, / are accessible. In “If“-statements even reference operators can be used. In pH Calibration slope and zero point can be documented in a result variable. It is the only way to document the current values for slope and zero point. For further information on the use of the formula editor refer to chapter 4.3 and 4.4.

4.2.7. Repetitions Repetitions can be used for e.g. recording measuring values or of repeating titrations. The function will be selected via “Operation“ “Repeat“.

For setting the number of repetitions the formula editor will be started. The number of repetitions can be a numerical value or a calculated variable.

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4.2. Creation of a Method 4.2.8. If-Statements

4.2.8. If-Statements The “If“ – statement will be selected via the menu item “Operation“ “If-Statement “. The if-statement will be used to carry out a e.g. titration with different reagents. The following applications will be carried out:

Titration with acid or leach in dependence of a start-pH value. Titration with different concentrations in dependence of a start potential. Titrations with differently set linear step lengths in dependence of a potential.

The function consists of three elements:

If-Statement Else-Branch End if

In the if-statement the criterion will be entered by means of the formula editor. Mostly, a variable, e.g. a measuring value with a reference value, will be compared by means of a logical operator. Thus, it is possible to decide if it should be titrated with acid if the last pH-measuring value is above pH 7. In the first step a measuring value pH will be taken. Then, this pH-value will be taken as decisive criterion in the if – statement. Thus, it is advisable to have this value precisely enough and stable. Then, the if-statement will be selected. By double clicking with the mouse the formula editor appears. Via “Values“ the end value pH will be selected. As reference criterion “>“ or “>=“ can be used, then the pH-value will be entered. The formula will be finished with “ok“. With marked if-statement a module titration will be inserted. By double clicking with the mouse the module can be edited. Then, it will be titrated with acid in this module. Subsequently, the “Else“-branch will be marked and an additional titration will be inserted. By means of a double click it will be edited and can be adjusted for the titration with leach.

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4.2. Creation of a Method 4.2.9. I/O-Connection

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At first, a pH-value will be recorded during the flow, and then, it is to be decided whether the titration will be carried out with acid or leach. An else-branch must not contain a module, it simply will be ignored. Another example is a chloride-titration, in which it will be titrated with different silver nitrate concentration due to the start measuring value. The lower the start measuring value is, the more concentrated is the silver nitrate solvent. In this case it is necessary to solve with multiple if-statements in the respective else-branches cording to the scheme:

If V < 0 mV then titrate with 0,1 mol/l AgNO3, else If mV < 50 mV then titrate with 0,05 mol/l AgNO3, else If mV < 100 mV then titrate with 0,01 mol/l AgNO3, else If mV >= 100 mV then no chloride is in the sample

The numerical values depend on the sample matrix, the electrode and its condition and, thus, can only be first indication for the experimental determination of numerical values. Such an example can not be realized with all chloride applications.

4.2.9. I/O-Connection Input (I) and Output (O) connections are located at the following devices:

TW alpha plus (TW alpha, TW 280) T 110 plus T 110 T 200

There, it is possible to connect units with relays, with which processes can be automated. Since this procedure is often combined with special requirements, please contact Schott Instruments if you want to control external devices. The selection for the control-procedure will be carried out in the menu “Utils” via “IO Box”.

After the device has been selected with the IO-Box, the switch will be entered and turned on or off for the time period entered. For the number of the electrical connections please refer to the device’s user manual.

4.2. Creation of a Method 4.2.10. Command

4.2.10. Command All devices communicate with the PC via commands. The commands are structured according to the following scheme:

Address from 00 to 15 Command with 1-3 signs Parameters as number or letter

The list of commands every device accepts can be taken from the operating manual. Basically, every command has the same functionality with every device. Here are some examples for a connected TL alpha plus with the address 01:

O1BF Fill buret 01DO10.00 Dose 10 ml

All commands are provided with a so-called “Timeout“ of approx. three minutes. If a device does not directly respond to a command (e.g. since the execution takes too long), it can take up to three minutes until a subsequent reaction is carried out. Typical applications are:

Fill buret at a particular place Adjust input delay for titrations in organic media

The selection is carried out via “Utils” “Direct command“.

Every command must be entered with the address and the command by means of capital letters. A parameter which is possibly necessary will directly be added. Decimal separator is always the dot.

4.2.11. Screen Message A screen message can be inserted at any place of an analysis flow. Various applications are possible:

Manual addition of auxiliary solvents of buffers. Advice for changing top sections. Advice for the procedure of analyses flows. Wait until a button was pressed. Control messages for analyses flows during the development of methods.

The selection is carried out via “Utils” and “Messagebox“. Other inputs are not possible during this process.

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4.2. Creation of a Method 4.2.12. Stirring Speed

By double clicking the mouse the input window opens up. Now, it is possible to enter a text which will then be shown during the analysis flow.

4.2.12. Stirring Speed The stirring speed can be adjusted at the sample changer, the TL alpha or the TR 250. With the TL alpha plus the stirring speed will be adjusted manually. Within a titration the stirring speed will be selected independently. The stirring speed always refers to the configuration, in which only one titration can be carried out at a time. The selection is carried out via “Utils“, “Stirring speed “.

The stirring speed can be adjusted from 0 to 9 in 10 steps. If a manual controller has been set onto a particular step, a fine adjustment can be carried out in ten steps.

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4.2. Creation of a Method 4.2.13. Reset Curves

Attention: It is possible that a manual controller (e.g. at the sample changer) is switched off. Then, it will not be stirred! The sample changer starts to stir gradually, since otherwise a magnetic stirring staff will jump around in the tumbler. The final stirring speed will be been reached after approx. 10 seconds.

4.2.13. Reset Curves All volumina and measuring values recorded in a analysis flow will be merged in a curve representation. If, for instance, in a flow will at first be titrated with sodium hydroxide solution and subsequently with hydrochloric acid, the titration curve will firstly show the rising part with the sodium hydroxide solution and then the falling part with the hydrochloric acid. In order to show only the falling part of the hydrochloric acid, a module „Clear curve“ will be incorporated after the titration with sodium hydroxide solution. This module is available under “Utils” and “Clear curve “. In the data base only the values after the module “Clear curve” will be saved! If the data should be available previously, it is necessary to titrate in two analyses. It is also possible to use a formula in certain places, in order to save the volumina at these places and to avoid the module “Clear curve“.

In practice this module will often be used to save the succeeding data relevant for the calculation after setting the pH-value. With a screen message it is possible to e.g. announce this.

4.2.14. Delay time Delay times can be inserted at any desired place into a analysis flow. They will be inserted in order to provide for a distribution within the titration vessel or even for an adjustment of the measuring value after e.g. reagent additions. The selection is possible via “Utils” and “Delay times “.

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4.2. Creation of a Method Input Box

The time will be entered in whole seconds. At the lower verge of the screen a message appears and the running seconds will be shown.

4.2.15. Input Box Since certain messages on the screen prevent an input of values or data (due to the fact that they must be receipted previously), a special window is necessary if data can be entered not until the execution of a titration. If e.g. the window “Messagebox“ appears, no other input is possible until “OK“ has been clicked on with the mouse. One application is the input of a weighed sample which has firstly been determined during or after a titration. The selection is carried out via “Utils” and “Input box “.

It is possible to enter a screen message such as “Enter weight sample” and the entered value can be allocated to any desired variable. In the lower example the result variable “Result” has been selected.

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4.2. Creation of a Method Titration Types and Their Parameters

4.2.16. Titration Types and Their Parameters TitriSoft allows four pre-defined titration methods:

End point titration Dynamic titration Linear titration pH-Stat-titration

The types of titration will be used for typical titration-applications:

Type of Titration Typical Applications Endpoint-Titration Covention-method, to achieve comparable results

Many pH-titrations in water and environmental ranges Overall-acid in watery solvents pH-titrations in the food sector

Dynamic Titration Determinations of contents Chloride titration Redox titrations

Linear Titration Titrations in organic solvents Titrations with very low contents Many titrations with ionic-sensitive electrodes Titrations with noisy measuring values

pH-Stat-Titration Determination of enzyme activities Extraction processes Stability processes pH-Adjustments along longer times

For the endpoint-titration the following parameter will be adjusted:

Parameter Meaning End Value (Unit) The endpoint of titration, the point at which titration is finished.

The value is entered as a formula. A comma functions as the decimal separator.

End Volume The maximum volume of titration, even if the endpoint is not reached yet. Ensures that the titration vessel does not overflow, if forgotten to attach an electrode. The value is entered as a formula. A comma functions as the decimal separator.

End delay The endpoint must be stable awhile, to be accepted as such. The duration is entered in seconds, often, 10 seconds are common.

Linear Step The last part of titration can be titrated with adequate small steps. The step length is entered in ml. Common are 0,01 or 0,02 ml. For very precise titrations smaller steps can be entered. It is important to pay attention to not make the steps too small which inadequately slows down titration.

Delta Value This is the distance to end value in pH-units or the chosen unit with which the linear step is titrated. Common are 0,2 pH-units in some applications.

Titration slope The titration slope describes the adjustment of the step to the slope of the titration curve. If the titration curve is arduous, titration is made with small steps to make the calculated results more precise. In the flat part of the curve titration is made with bigger steps and thereby titration is accelerated. Titration curves are differentiated by means of pictographs:

steep decrease medium decreasing exact decreasing steep rise medium rising exact rising user adjustments (description see dynamic parameter)

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Titration speed The titration speed is adjusted with the drift. The drift is the potential change of a sensor over time, measured in mV/min. The following setups are possible:

turbo, without drift control fast (with many pH-titrations medium (e.g. chloride in many cases) exact (for especially exact titrations) user adjustments (see description in chapter about drift

control)

For dynamic titration the following parameters are adjusted:

Parameter Meaning Use end value If this point is marked, titration will be made up to the defined pH or mV-

value as termination criterion for titration. End Value (Unit) The end value of titration is the point when titration is finished.


End Volume The maximum volume of titration, even when the end volume is not reached yet. Ensures that the titration vessel does not overflow, if forgotten to attach an electrode. The value is entered as a formula. A comma functions as the decimal separator.

Number EQ’s During titration, EQ’s can be calculated. They only function as termination criterion for titration and are not connected with formula calculation. 5 EQ’s are possible, as a rule, one EQ is applied, or two (as in the case of phosphoric acid). Because a random EQ can be calculated with noisy titration slopes, these titration slopes break up too early. That is why titration parameters must be applied correctly and the electrodes have to be alright with these titrations.

Titration Slope The titration slope describes the adjustment of the step to the slope of the titration curve. If the titration curve is arduous, titration is made with small steps to make the calculated results more precise. In the flat part of the curve titration is made with bigger steps and thereby titration is accelerated. Titration curves are differentiated by means of pictographs:


Titration Speed The titration speed is adjusted with the drift. The drift is the potential change of a sensor over time, measured in mV/min. The following setups are possible:

turbo, without drift control

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fast (with many pH-titrations medium (e.g. chloride in many cases) exact (for especially exact titrations) user adjustments (see description in chapter about drift

control)

For linear titration, the following parameters are adjusted:

Parameter Meaning Use End Value If this point is marked, titration will be made up to the defined pH or mV-

value as termination criterion for titration. End Value (Unit) The end value of titration is the point when titration is finished.


End Volume The maximum volume of titration, even when the end volume is not reached yet. Ensures that the titration vessel does not overflow, if forgotten to attach an electrode. The value is entered as a formula. A comma functions as the decimal separator.

Number EQ’s During titration, EQ’s can be calculated. They only function as termination criterion for titration and are not connected with formula calculation. 5 EQ’s are possible, as a rule, one EQ is applied, or two (as in the case of phosphoric acid). Because a random EQ can be calculated with noisy titration slopes, these titration slopes break up too early. That is why titration parameters must be applied correctly and the electrodes have to be alright with these titrations.

Linear Step The linear step range in ml, which is adhered to constantly during the entire titration.

Direction The titration slope describes the adjustment of the step to the slope of the titration curve. If the titration curve is arduous, titration is made with small steps to make the calculated results more precise. In the flat part of the curve titration is made with bigger steps and thereby titration is accelerated. Titration curves are differentiated by means of pictographs:




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control)

For pH-titration the following parameters are adjusted:

Parameter Meaning pH-Stat Value The pH-Value, which ought to be held constant during titration. End Volume The maximum volume of titration, even when the end volume is not

reached yet. Ensures that the titration vessel does not overflow, if forgotten to attach an electrode. The value is entered as a formula. A comma functions as the decimal separator.

End Time [min] The duration of titration in minutes. Linear Step The last part of titration can be titrated with adequate small steps. The

step length is entered in ml. Common are 0,01 or 0,02 ml. For very precise titrations smaller steps can be entered. It is important to pay attention to not make the steps too small which inadequately slows down titration.

Delta Value This is the distance to end value in pH-units or the chosen unit with which the linear step is titrated. Common are 0,2 pH-units in some applications.

Measurement Interval [sec]

The pH-Value is held constant during the whole process. In the indicated intervals data points are saved to the database. During very long titrations one should pay attention not to create too many data points. As a general rule, more than 1,000 data points do not make sense, standard titrations have between 50 and 100 data points.

Titration Slope The titration slope describes the adjustment of the step to the slope of the titration curve. If the titration curve is arduous, titration is made with small steps to make the calculated results more precise. In the flat part of the curve titration is made with bigger steps and thereby titration is accelerated. Titration curves are differentiated by means of pictographs:




control)

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4.2. Creation of a Method 4.2.17. General Method Adjustment

4.2.17. General Method Adjustment The method is built up with modules. To carry out a titration, only one module titration is needed. There is no calculation, though. But then, there will be no calculation. Thus, the methods still have at least one calculation in practice. Therefore, it is recommended to include further elements into the method in order to improve the documentation:

The pH-value or measuring value prior to the titration often gives information on the sample

and will, in many cases, documented. In addition to the results the calculated EQ or the used EP should also be documented. The average value can be calculated automatically.

In many cases, methods contain even further elements such as dosages of auxiliary reagents or even further calculations. In the following method the most common elements will be inserted. On the left side is the inserted module, on the right side the associated comment. This example shows the chloride determination. Mostly, the start measuring value is only common with pH-titrations.

The start measuring value will be documented with two places after the comma, the respective variable is the end value mV, in this example a chloride titration.

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4.2. Creation of a Method 4.2.17. General Method Adjustment

The titration to determine the chloride will mostly be carried out dynamically. After the titration the buret will again be filled, in order to be able to change the top section. An mV-value of 260 mV, which is dependent on samples and electrodes, terminates the titration as an equivalent point or a maximum volume of 20 ml will do. The curve is steep or middle and will be carried out with normal speed.

The found and calculated EQ will be documented as first result. Thus, subsequent calculations can easily be carried out.

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4.2. Creation of a Method 4.2.18. Allocation Hardware

The result in % chloride calculated with all necessary data will be obtained in the following formula with a decimal. Often the titer of the reagent used will be added.

The average value will simply be obtained by an additional calculation. With the same sample designation in the sample list the average value will automatically be calculated.

4.2.18. Allocation Hardware An allocation to the hardware used you will obtain at many times in a method. Measurements are included both with a measuring value and within a titration in a method. In a method it is always possible to pick from all connected devices in a configuration. In the following example, a TL alpha plus with the address 1 and a T 110 with the address 2 are connected. It is possible to use all

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4.2. Creation of a Method 4.2.19. Dynamic Control

measuring possibilities of the TL alpha plus with all measuring values, with all dosing procedures it is always possible to select between both devices depending on the fact in which top section which reagents are located.

The display is constructed according to the scheme device-address-measuring input.

With dosing procedures the reagent will always be named separately. This is primarily necessary for the documentation and for subsequent calculation option, since every reagent is also connected with its titer. A check of the appropriate reagent in the top section is not possible, neither by the software, nor by the titration hardware. This is the exclusive responsibility of the user.

4.2.19. Dynamic Control Dynamic titration means a variable adjustment of the titration step range depending on the slope of the titration curve. The objective is to titrate in the flat part of the titration with both large steps and faster speed rates, whereas in the steep part of the curve, where normally the equivalence point will be calculated, the objective is to titrate with smaller steps in a careful and precise way. For many routine titrations this is the method of choice. Various procedures can be found in diverse literary publications. While linear or monotonous titrations titrate with equidistant volume steps, the dynamic titration uses equidistant potentials. The result is a curve in which the volume steps get continuously smaller with rising slopes. TitriSoft uses procedures that calculate the dosage directly in dependence of the slope of the titration curve. A potentiometric titration follows the equation of Nernst:

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This equation is a function of the natural logarithm in which the potential is proportional to the natural logarithm of the activities of all reactants involved.

The derivation and, thus, also the slope of the titration curve is the 1/x- function:

Therefore, TitriSoft uses a 1/x-function for the calculation of the currently best step ranges in direct dependence on the slope of the titration curve.:

The dosing step in ml is a parameter „a“ divided by the slope of the titration curve to the power of parameter „b“. From that, the result is a hyperbolic function in which the slope of the titration curve will be laid onto the x-axis, whereas on the y-axis the dependent dosage step will be laid on in ml:

Thus, with large values for the slope small step ranges are the result. With small slopes large step ranges are the result. The following illustration shows the curves for preset values for flat, middle and steep titration curves.

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Curve Shape Smallest Step Largest Step a b Steep 0,01 1,00 2,7 0,9 Middle 0,01 1,00 1,5 0,9 Flat 0,01 1,00 0,5 0,6 The following illustration shows the diminution of the step range as illustrated at the example of a chloride titration. The titration volume has been laid onto the x-axis, the first y-axis shows the mV measuring value, the second y-axis shows the step ranges of the titration up to the equivalence point.

In praxis, it is common to aim at multiple equidistant volume steps for the EQ-range. The following example shows the titration of all steps from 4,84 to 5,03 ml with 0,01 steps (with one exception). Here we use the standard settings for middle titration curves.

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The risks of the dynamic titration are titration curves that are noisy or also very flat. This can cause noisy titration steps where large and small steps alternate. Thus, it is normal to titrate titrations in organic solvents linearly and not dynamically. Often, a defective electrode or an un-kept sensor is the cause for noisy titration curves. These two illustrations below with settings of dynamic titrations allow manual manipulations, firstly for rising and, secondly, for falling titrations. The step range will be determined in dependence on the application. Titration steps that are too small often cause results that are not exact since they produce noises. For a chloride titration more than small steps between 0,02 and 0,05 ml will be used. For the determination of carbonate within a sodium hydroxide solution it is even possible to use 0,01 steps. The largest step range is between 0,2 ml and 1,00 ml, in dependence on the curve shape and the overall consumption. A dynamic titration can titrate very precisely with 50 measuring points in total.

Both parameters “a“ and “b“ can thus be calculated within an Excel-Chart.

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4.2. Creation of a Method 4.2.20. Drift Control

The following facts will be obtained from the titration curve:

The slope from which it is to be titrated with smallest volume steps (slope steep) The step range in ml for these smallest steps (ml_min) The slope of the titration curve up to which it is to be titrated with the largest step ranges

(slope flat) The step range of the largest step range (ml_min)

Then it is possible to obtain the values for the parameters a and b from the Excel-Chart. Please note: During the titration process the titration curves will be smoothed by polynomial approximations in dependence on the number of data points. The values which have been calculated with Excel are thus only approximate values and can not be considered as exact values. The EQ-sensitivity is one criteria for the EQ-detection as abortion criteria for the titration. It has nothing to do with the calculation of the EQs after the titration in the formulas. This value of the first derivative will be entered for which it is just possible to detect an EQ. The value should be significantly higher than the values that have caused the noises. There are no general recommendations since the values of the first derivative depend on multiple factors:

Step range Concentration Curve shape Consumption

4.2.20. Drift Control The drift describes the setting of a stable measuring value at a sensor. The duration of such a setting procedure can here be in the range of seconds to minutes. Normally, asymptotic adjustments to a stable final value are typical.

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4.2. Creation of a Method 4.2.21. End Criteria

Measuring values are immediately stable at the beginning of a titration since the potentials do hardly change. In the range of a potential step the adjustment of a measuring value takes significantly longer. In case of a titration it is not always possible to wait until the balance has been generated. In many cases the titration takes between three and five minutes and has between 30 and 100 measuring points. Thus, there is no time to create the equilibrium for each measuring point.

With four parameters it is possible to control the creation of the equilibrium. It is necessary to define a measuring interval in seconds in which a stability criterion must have been met. The duration will here be limited by a minimum and a maximum time. The maximum duration should be measured in a way that the titration will have ended within a reasonable time frame. The minimum duration must at least be as long as the measuring interval.

4.2.21. End Criteria The end criteria are, besides the calculation of the step range and the consideration of the drift, additional titration parameters. Depending on the type of titration it is the titration volume, the measuring value, titration time and/or the number of equivalence points that are the criteria which end the titration. For the dynamic titration the following endpoint criteria are possible:

Measuring value, e.g. pH or mV Titration volume Number EQs The curve shape as direct criterion for the height of the first derivative for EQ detection

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In order to use a measuring value as abortion criterion it is necessary to tick off the item „Analyze Endpoints“. The value for this endpoint, the last point of the titration curve, will be stated in mV, pH or any other unit. The curve shape is the decisive factor that decides whether the titration is falling or increasing. In case a measuring value is 100 mV and the titration direction is increasing, the titration starts and ends with 260 mV. In case the starting measuring value is above 260 mV, the titration will not start at all. A volume will always be stated, in order to prevent the titration vessel from flowing over. It would also end a titration if the reagent would run dry in the middle of the titration process. EQs as abortion criteria take care for the appropriate measure of reagents, i.e. that not more reagent is used than needed. By means of the slope of the titration curve the criteria will be determined as value for the first derivative. Noisy titration curves, slow electrodes or in case of specific applications, apparent EQs can abort the titration even at a premature stage. If the titration results have a bad reproducibility, noisy titration curves can be the cause within the EQ-range. They will be visualized by means of the first derivative in a very good manner. In order to calculate an EQ it is always necessary to over-titrate some steps since the inflection point of the titration curve must be calculated. TitriSoft uses the maximum of the first derivative for the calculation of the EQs.

The “Linear titration“ has the same abortion criteria.

By means of the linear steps the first derivative will often become flatter so that in case of some curves the EQ-criterion does not make much sense.

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The endpoint titration is a conventional method that emphasizes comparability. Normally, it stops at the endpoint which is at the same time the point of the titration curve.

For the EP-titration the following endpoint criteria are possible:

Measuring value, e.g. pH or mV Titration volume Duration, which must be exceeded by the endpoint Step range with which the last titration steps must be carried out. If the difference is smaller

as a defined value “difference to endpoint” to the endpoint, the step range amounts to the value „linear step range“..

In the example underneath the last three 0,3 pH-units before the endpoint 260 mV will be titrated with 0,02 ml steps. The precision with which the endpoint is to be reached is dependent on the step range. The smaller the step range, the more precise is the way in which the endpoint will be reached. For steps that are too small there is the risk that extraneous influences compensate the reagent measure and that the endpoint will not be reached or only at a very slow speed.

pH-Stat-titrations usually consist of two steps. In a first step, the pH-value, which must be kept at constant levels, will be reached, i.e. will be “pre-titrated“. Now, in a second step, this pH-value will be stabilized and kept at constant levels. Often, the first part is carried out quite fast and needs much reagent with some applications.

For the pH-Stat-titration the following endpoint criteria are possible:

Measuring value which must be kept at constant levels, e.g. pH or mV Titration volume

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4.2. Creation of a Method 4.2.22. Dynamic Titration

Duration of titration Measuring interval in which the measuring values are to be entered for the titration curve

which has been saved in the data base. If a titration takes ten minutes and a measuring value is taken every 20 seconds, the titration curve has 30 measuring values. The step range with which the last titration steps are to be carried out. If the difference is

smaller than a defined value „difference to endpoint“, the step range amounts to the value “Linear step range“.

4.2.22. Dynamic Titration The dynamic titration is a method with which it is possible to carry out precise content determinations for many applications. Normally, this method is fast and precise. Typical applications are:

Chloride titration Redox titration with Thiosulfat Contents of acids and alkaline

The parameter of a dynamic titration are:

Parameter Meaning Analyze Endpoints End criterion for the titration. Will often be used if electrode potentials

are relatively stable and the applications do not differ very much within their conditions.

Endpoint Value The numerical value for the end criterion. In this example typical for the chloride titration with 0,1 molar silver nitrate solution and an AgCl 62 electrode.

End Volume Abortion criterion as security, in order to prevent a titration from taking to long and that the titration vessel does not overflow.

Number EQs Abortion criterion, can include risks if the titration curve is noisy. Curve Shape Determines the control of the step range for the titration. The following

possibilities can be selected: Steep curve falling (e.g. COD) Middle curve falling (e.g. Thiosulfat) Flat curve falling (Ca/Mg) Flat curve rising (Chloride in the range of traces) Middle curve rising (Chloride) Steep curve rising (Hydrochloric acid with sodium hydroxide

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4.2. Creation of a Method 4.2.23. Linear Titration

solution) User settings falling User settings falling

Titration Speed Determines the drift and thus influences the titration speed. The

following settings are possible: Turbo (no drift control) Fast (fast with slight drift control) Normal (with drift control, appropriate for many applications) Precise (with drift control for precise titrations or e.g.

precipitation titrations) User settings with drift criteria and limitation to minimum and

maximum duration of drift control.

The titration curve shows a bromide/chloride – titration. The first steps are bigger and will grow smaller onto the first EQ (bromide). The second EQ (chloride) will also be titrated with smaller step ranges. After the second EQ the titration curve will become flatter again and the step range grows. Thus, it is possible to carry out the calculation of the EQs in a very precise manner.

4.2.23. Linear Titration The linear titration has advantages for the following applications:

Noisy measuring values or slow electrode Titrations in organic solutions (TAN, TBN….) Titrations with small potential changes (e.g. ISE electrodes) Conductibility titration Photometric titrations

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4.2. Creation of a Method 4.2.23. Linear Titration

Determination of equilibrium constants By mathematic interpolation between the measuring points it is possible that a titration with comparably large step ranges can have very precise results for stable measuring values. The linear titration will often be used for the first inspections of a new sample in order to be able to titrate the succeeding samples with optimized parameters. The linear titration will be selected at “Loop type“.

Parameter Meaning Analyze Endpoints End criterion for the titration. Will often be used if electrode potentials

are relatively stable and the applications do not differ very much within their conditions.

Endpoint Value The numerical value for the end criterion. In this example typical for the chloride titration with 0,1 molar silver nitrate solution and an AgCl 62 electrode.

End Volume Abortion criterion as security, in order to prevent a titration from taking to long and that the titration vessel does not overflow.

Number EQs Abortion criterion, can bear risks if the titration curve is noisy. Especially with flat titrations curves the values are so small for the first derivative that a secure differentiation between noise and maximum i soften not possible. The value for the first derivative as criterion is only indirectly accessible: At first select „Dynamic Titration“, now select the curve shape in „User Settings“, enter the value for the first derivative, back to titration type and select “Linear Titration”.

Linear Step Range Step range for the titration. As rough recommendation 50 to 100 measuring points should be saved within a titration curve. For specific applications it is also possible to use more (pH-Stat) or even less (TAN, TBN).

Curve Shape Determines the control of the step range for the titration. It is possible to choose the following possibilities:

Curve falling Curve rising

Since it is not necessary to adjust the curve in one particular form, further selection possibilities are not necessary.

Titration Speed Determines the drift and thus influences the titration speed. The following settings are possible:

Turbo (no drift control) Fast (fast with slight drift control) Normal (with drift control, appropriate for many applications) Precise (with drift control for precise titrations or e.g.

precipitation titrations) User settings with drift criteria and limitation to minimum and

maximum duration of drift control. For titrations in organic solvents, especially in non-polar aprotic solvents, it is often titrated with fixed waiting periods since the potentials often fluctuate. But potentials are reproducible if the electrode will be stored in the same solvent in which also the titration will be carried out. The steps will become better if the electrodes will be conditioned in water and diluted acids between the titrations.

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4.2. Creation of a Method 4.2.24. End Point Titration

In this titration example for calcium and magnesium with EDTA there are two EQs. The first step will be allocated to calcium. If the portion of magnesium is very small, the steps will merge together and often the Ca-step will not be analyzed correctly. If the step range is too small, as it can happen with the dynamic titration, the curve will become very noisy due to the relatively small potential changes, and, thus, the Ca-content will not be calculated very precisely. For this application it is thus often necessary to titrate linearly and, in crucial cases, to use standard extras of magnesium.

4.2.24. End Point Titration The endpoint titration is a convention method. Here, it will be titrated on a fixed measuring value, which has once meant a color change. Thereby, it is possible to achieve a very good comparability with previous titration results which have been titrated towards a color change manually. Always in this cases in which comparability, e.g. with a large number of comparative data from a long period of time, is more important than the exact analytical content, the endpoint titration will be used. The different concentrations in a sample will lead to different pH-values of the equivalence points. Thus, an end point titration is, in comparison to the dynamic titration, only second choice.

The parameters of the end point titration are:

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4.2. Creation of a Method 4.2.24. End Point Titration

Parameters Meaning Value for end point The numerical value for the end criterion. In this example pH 7 for a

total acid determination, as often practiced in the food sector. Duration endpoint reached The endpoint must be exceeded for a particular time. Often it is ten

seconds. In individual cases this can take longer or even shorter. This allows for a hesitant adaptation of the electrode or acid output of the sample.

End volume Abortion criterion as security, in order to guarantee that a titration does not take too long and that the titration vessel does not overrun.

Linear step length Step length for the last part of the titration. Thereby, it is ensured that it will neither be over-titrated in too large steps, nor the endpoint will be reached in too little steps. The linear step length will be used as soon as the current measuring value has exceeded the difference to the endpoint.

Difference to end point Defines, together with the end point, a window in which it will be titrated with the linear step length.

Curve shape Determines the control of the step length for the titration. The following possibilities can be selected:

Steep curve decreasing (e.g. COD) Middle curve decreasing (e.g. Thiosulfat) Flat curve decreasing (Ca/Mg) Flat curve rising (Chloride in the traces range) Middle curve rising (Chloride) Steep curve rising (hydrochloric acid with sodium hydroxide

solution) User setting decreasing User setting decreasing

Titration speed Determines the drift and has thus influence on the titration speed. The following settings are possible:

Turbo (no drift control) Fast (fast with minimal drift control) Normal with drift control, appropriate for many applications) Precise (with drift control for precise titrations or e.g. precipant

titrations) User settings with drift criteria and limitation to minimal and

maximal drift control.

The end point will not exactly be reached, it will be exceeded with the final titration step. In many titrators the consumption of the desired end point will be re-calculated and the target-pH of the end point will be stated. Since the step lengths are very small in the end point range, usually around 0,01 ml, this is not relevant in practice and the actual and measured end value will be specified. In order to achieve the desired accuracy, it is possible to define the step length in the range or the end point. The titration will be carried out dynamically, according to the selected curve shapes and the drift defined. Only the last “Difference to the end point“ range will be titrated with the defined linear step length. It is usual to titrate 0,2 pH-units with a step length of 0,01 ml.

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4.2. Creation of a Method 4.2.25. pH-Stat Titration

Endpoint Titration

6,50

6,60

6,70

6,80

6,90

7,00

7,10

10,00 10,10 10,20 1

ml NaOH 0,1 m

pH

In order to achieve the desired accuracy, it is possible to depoint. From the end point the value of the “Difference toexample the end point is 7,00 pH and the difference to the titrated from pH 6,00 with the defined linear step lengtdependent on the application. The following issues must be

Too small steps can cause that the end point wilwith the titration with alkali Too large steps result in an over-titration

Endpoint Titratio

6,60

6,70

6,80

6,90

7,00

7,10

7,20

10,20 10,25 10,30 10,35

ml NaOH 0,1 m

pH

4.2.25. pH-Stat Titration The pH-Stat titration is used to keep a measuring value (nperiod of time. Applications can be:

Titration of enzyme, such as Pankrease

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0,30 10,40 10,50

ol/l

fine the step length in the range of the end the end point“ will be subtracted. In this end point is 0,2 pH units. This range will be h of von 0,01 ml. The optimum value is considered: l never be reached, e.g. by CO2-absorption

n

10,40 10,45 10,50

ol/l

Difference to the endpoint is titrated in the defined step size

ormally a pH-value) constant for a defined

4.2. Creation of a Method 4.2.25. pH-Stat Titration

Titration of soil samples Eluation of concrete samples …and much more

The pH-Stat titration will be selected under Loop type“. pH-Stat titrations normally consist of two steps, a first step in which the ph-value to be kept constant will be reached, i.e. will be aimed at with the titration, and a second phase in which this ph-value will be kept constant. The first part will mostly be carried out very fast and needs with some user much reagent.

The parameters of the pH-Stat titration are:

Parameter Meaning pH-Stat value The pH-value which will be aimed to be titrated and which will be kept

constant. Duration of the titration [min]

Duration of titration in order to keep the set value constant in minutes. Conversion of units: Seconds Minutes Hours Days 60 1 120 2 600 10 3600 60 1 86400 1440 24 1 10080 168 7

End volume Abortion criterion as security in order to guarantee that the titration does not take too long and that the titration vessel does not overrun.

Linear step length Step length for the last part of the titration. Thereby, it is ensured that it will neither be over-titrated in too large steps, nor the endpoint will be reached in too little steps. The linear step length will be used as soon as the current measuring value has exceeded the difference to the endpoint.

Difference to the end point (delta value)

Defines, together with the end point, a window in which it will be titrated with the linear step length.

Measurement interval [sec] Measuring interval in which the measuring intervals will be entered for the titration curve saved in the data base. If a titration takes ten minutes and a measuring value will be recorded every 20 seconds, the titration curve has 30 measuring values. The pH-value will also be kept constant in between this intervals. Since in the most cases either the end consumption or the slope of a straight line needs consumption per time, a high density at measuring points is in many cases not necessary and only takes resources of the computer.

Curve shape (Titration slope)

Determines the control of the step length for the titration. The following possibilities can be selected:

Steep curve decreasing (e.g. COD) Middle curve decreasing (e.g. Thiosulfat) Flat curve decreasing (Ca/Mg) Flat curve rising (Chloride in the traces range) Middle curve rising (Chloride) Steep curve rising (hydrochloric acid with sodium hydroxide

solution) User setting decreasing User setting decreasing

Titration speed Determines the drift and has thus influence on the titration speed. The following settings are possible:

Turbo (no drift control)

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4.3. Calculation of a Result 4.3.1. Creation and Editing of a Formula (Creation and Editing)

Fast (fast with minimal drift control) Normal with drift control, appropriate for many applications) Precise (with drift control for precise titrations or e.g. precipant

titrations) User settings with drift criteria and limitation to minimal and

maximal drift control.

4.3. Calculation of a Result Results must be calculated with a formula! No result will be calculated automatically. However, every titration curve or measurement will be saved in the data base. All information that are necessary after a measurement must be converted into a documentable format by means of a formula. A global description is located in chapter 4.2.6. A subsequent calculation via formulas in the data base is possible. In this case, the titer of the reagents is not available, in order to avoid the usage of defective titer values, which are out of date.

4.3.1. Creation and Editing of a Formula (Creation and Editing) The calculation will be inserted behind a titration or a measuring value in a analysis flow as a module.

The order depends on what is to be documented. If a measuring value is to be documented, a formula will be inserted directly behind the measuring value in the analysis flow. In the formula the end value of the measuring value will be selected from the menu Values. Thus, it is always possible to have access to all values recorded in the method so far and the calculated (…). The most important field of application is probably the formula usage after a titration for the calculation of a equivalence point and the result. If the module has been selected, it will then be opened for the editing process with the mouse via double clicking. The following inputs are necessary:

Parameter Meaning Type (of variable) The type of variable will be shown, it can not be selected. The

information is important e.g. if variables such as individual titer and complete titer as average value must be differentiated.

Name The name can be selected from a list. Always the type of variable and

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the name will be shown. With the variable type result the name can be also be entered directly.

Number decimal places The number of decimal places of the result, which will later on be shown in the documentation and which will be saved in the data base.

Number EQs Here, the number of equivalence points will be entered which are to be available in the calculation formula.

Formula By clicking the points in the marked line (it will be highlighted in dark red), the actual formula editor will be opened.

Smoothing The degree of smoothing for noisy titration curves can be adjusted. Good effects can be achieved with relatively flat titration curves. The algorithm bases on a „Moving average“, with which the number of the data points, via which it will be smoothed, will rise with increasing smoothing degree. The smoothing can be adjusted in multiple stages. The stages are:

Strong Middle Weak

Window for volume An analysis window will be used to limit a range for a equivalence point to be calculated. It is possible to enter a value for the smaller ml-value and a value for the bigger ml-value. The equivalence point will then be calculated between the ml-values. The window must contain enough data points (minimum seven) and the criteria for an EQ must be fulfilled.

Window for measuring value

An analysis window will be used to limit a range for a equivalence point to be calculated. It is possible to enter a value for the smaller ml-value and a value for the bigger ml-value. The equivalence point will then be calculated between the ml-values. The window must contain enough data points (minimum seven) and the criteria for an EQ must be fulfilled. Both analysis windows can be combined.

As it is possible for every module, it is possible for every formula to enter a comment. For this the comment box besides module will be marked.

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In the opening field any unformatted text can be entered. With OK the text will be confirmed and accepted. ATTENTION: A text will only be saved in a method if subsequently the method will be saved as a whole.

In the lower example one equivalence point will be calculated in ml-units, with three places after the comma, without smoothing but within a window between 50 and 180 mV and between 1 and 50 ml. A typical formula for the calculation of a EQ for a chloride titration. A small increase at the beginning of the titration will thus not accidentally be regarded as an equivalence point. ATTENTION: The measuring value and consumptions differ from electrode to electrode and are strongly dependent on the chemical conditions of the application.

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4.3. Calculation of a Result 4.3.2. Concept of the Variables in a Formula

Subsequently, for a chloride application the chloride content will be calculated in %. Thereby, it will be referred to the already calculated result. Thus, it is not necessary to set an analysis window and there is no risk that, due to different criteria, different EQs will be calculated. At least, it is easily to recognize. The designation “Chloride in %“ will be entered directly in the field “Name“. Since this is a result variable, it needs, by contrast to other variables, previously not to be created.

The example shows a formula for the calculation of the chloride content in %. Here the following issues mean:

Result[„2,EQ in ml“] A (previously calculated) equivalence point selected 35,45 Atomic weight of the chlorine 0,1 Molarity of the silver nitrate solvent, of the titration reagent. 100 Conversion in % / Fraction stroke Amount Sample amount 1000 Conversion from g into mg () The brackets

The usual mathematical calculating rules apply. Thus, the e.g. omission of the brackets would mean that the term will previously be divided by the sample amount and the obtained value will be multiplied with 1000, which would cause another result. The values within a formula can be entered “Manually“ or be selected from the menus. Usually it is advisable to enter the numerical values manually and to select the variables from the menu.

4.3.2. Concept of the Variables in a Formula TitriSoft has the following types of variables:

Results: Results that are only known within the method. They will be used to document measuring values, consumptions or even (calculated) titration results. Chemicals: They contain the value for the titer with the determination time and limits. They

are known to all methods. The allocation of the values is automatically carried out within a method if a in titration a reagent will be selected. Globals: Global variables that are known to all methods. Thus, they will be used to transfer

values between methods, such as blank values. Such variables can also be used as nominator or even for many other purposes. Sample Data: User-defined variables which can be entered into the sample list Values,

which will be used in the calculation of the method. Typical examples are e.g. density of solutions that will not be weighted-in and solids content of plastics. It could also be a correction factor for humidity in order to correct a weighted sample. Electrodes: Ionic sensitive electrodes whose calibration values will be saved here.

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All variables will be defined by marking the respective type of variables on the left side of the screen and by selecting the menu item “Characteristics“ (Results?). Then, a variable can newly be created or a marked version can be deleted.

For a result designation and unit will be entered together in one field. It is possible to specify limits for the results. If a result is outside the limits, it will be color-coded.

If “Chemicals“ will be marked on the left side, on the right side it appears a summary chart listing all reagents already existing including their characteristics.

The parameters of the “Chemicals“ are:

Name Value of the titer (or specification of the concentration) Minimum value of the titer Maximum value of the titer Date and time of the last automatic determination

If a titer is outside the limits, it will be color-coded. However, it is always possible to work with the titer value. In a formula the value will always be provided for further usages when the reagent will be used in the method, independent on dosing or titration processes. The recommended proceeding for the determination of a titer is the automatic determination by means of a titration with a standard. Firstly, in such a method the EQ will be determined, then in a further formula the result variable Individual Titer and, lastly, as average value of the individual titer the variable “Chemicals“ which has been picked from the list.

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If “Globals“ will be marked on the left side, on the right side it appears a summary chart listing all sample variables already existing including their characteristics.

The parameters of the “Globals“ are:

Name Value of the global value Minimum value of the global value Maximum value of the global value

If a global value is outside the limits, it will be color-coded. However, it can always be worked with the global value. In a formula the value will always be provided for further usages. A value for the global memory can be entered into a chart or can be allocated in a formula. Usual usages of global memory values are blank values or other values that are to be transmitted between methods.

If „Sample Data“ or sample variable will be marked on the left side, on the right side it appears a summary chart listing all sample variables already existing including their characteristics.

The parameters of the “Sample Data“ are:

Name Value of the sample variable Minimum value of the sample variable Maximum value of the sample variable

If a sample variable is outside the limits, it will be color-coded. However, it can always be worked with the sample variable. In a formula the value will always be provided for further usages. A value for a sample variable can be entered in different ways:

Can directly be entered in the list. Can be allocate in a list Can, after the variable has added to a sample list manually, be entered in this sample list

and be used for the calculation of this sample Examples for sample variables are density, solids content, variable sample volumina or the like.

4.3. Calculation of a Result 4.3.3. Calculation of an EQ of a Potentiometric Curve

One additional possibility to enter sample-specific values is the input field. This input field offers the possibility to enter a value for this sample during the flow of the analysis. Thus, it is possible to e.g. enter a value for the weighted sample from a return weighting even prior to the calculation. The content will be saved in a result variable. The entry can be a numerical value or even a comment, depending on the usage of the variable. If the entry will be confirmed with the ENTER-button, there is a check of the input as numerical value. If the ENTER-button will not be pressed, but confirmed with OK, comments will be possible as input. Respectively, these comments can be documented.

The input field can be located at any desired place in a procedure. If, however, the input is to be used in a formula, the module must be positioned in front of the formula. The characteristics are:

A message, which will be shown during the titration. The type of variable, in which the information is to be saved. The value of the variable, in which the information is to be saved.

4.3.3. Calculation of an EQ of a Potentiometric Curve An equivalence point can only be calculated via a formula. For this, a module “Calculation“ will be inserted after the titration. Via double clicking the module will be opened and can now be configured. The characteristics of a formula have already been described. For an EQ calculation the following issues will be entered:

The type of variables can not be selected, but will be shown according to selection.

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4.3. Calculation of a Result 4.3.4. Calculation of an EQ of a Conductivity Curve

Result name The number of decimal places The number of equivalence points (from 1 to 5) The formula

The formula editor will be opened by clicking on the three points, which appear when the line is marked.

In the formula the menu item “EQ“ will be selected under Calculation. It is only possible to select from the number of EQs specified in the general settings. Then, the EQ will be represented in a formula and can be used at all places within the calculation formula.

The algorithm bases on the calculation of the first derivative. The maximum of this derivative will be regarded as inflection point and equivalence point. Thereby, the derivative of the titration curve will gradually be checked for maxima. One maximum will be detected if two data points are previously and later on smaller. The so detected maxima will be sorted according to the size of the numerical value and will be processed by a polynom of the second degree. This polynom will be calculated explicitly, its maximum must comply with the criteria, i.e. its derivative, a linear equation, must be zero.

4.3.4. Calculation of an EQ of a Conductivity Curve An equivalence point on the basis of a conductivity titration will be calculated in another way. The selection is carried out in the formula editor under „Calculation“ and “LF“. The titration curve will be checked for an inflection point and, subsequently, a straight line will be calculated from the beginning of the titration curve and an additional straight line from the end of the titration curve. The inflection point of both straight lines is the LF-equivalence point. If an evaluation window has been set, only data within the analysis window will be considered.

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4.3. Calculation of a Result 4.3.5. Calculation of an EQ of a Photometric Curve

4.3.5. Calculation of an EQ of a Photometric Curve In most cases, photometric titration curves can even be determined by normal EQ-calculations. However, in a large number of cases, the photometric EQ will be calculated in a more exact way in other manners and will then better comply with the optically-detected EQ. The steepest part of the titration curve will be determined and a (vertical) straight line will be calculated through this part. Then, best fit straight lines will be calculated from the beginning and from the end of the curve. These best fit straight lines make up inflection points with the vertical straight line. The first inflection point with the smaller volume is “%T (1)“ and the second inflection point is „%T(2)“. In a descriptive way the first inflection point can be compared with a color that appears right now, the second inflection point with a color that right now disappears. Since this subjective impression is also dependent from the wave length, the optimum settings for an application must be worked out by means of experiments.

4.3.6. Creation of a Formula The following menus are available for a formula:

Values for variables in the formulas Calculation for the calculation of equivalence points Functions such as brackets or logarithmic functions Operators such as plus and minus pH-calibration in order to document the current steepness and zero point of an electrode.

Numerical values will directly be entered. Variables should directly be selected from the menu, since otherwise erroneous inputs are easily possible. Operators can be selected or can also be entered. NOTE: Formulas can be copied into the clipboard of WINDOWS with the shortcut <Strg> + <c). Then, they can be copied with the buttons < Strg> + <v> into an editor or into another formula. The following variables are available as values: Designation Meaning Description

Weighted sample

Also „amount“ Every form of the sample amount, be it sample volume or weighed sample. The value can be entered in the titration – center for every sample.

End volume End volumes of all reagents. I fit has been titrated with two reagents, the volumina will be added.

Globals Global Variable Global variables will be used to exchange values between methods. Such as blank values, nominator or other.

Sample Data Sample variable Sample variables behave like global variables but can, additionally, be entered as values into the sample lists in the titration –center, e.g. sample-specific density.

End Values End value The last measuring values of a measurement or titration. If many measuring values have been recorded in a method, there are also end values available.

Volume Chemicals

End volume Reagent Here, the end volumina of all reagents used in a method are available,

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4.3. Calculation of a Result 4.3.6. Creation of a Formula

Titer Titer The titer of the reagents. It behaves like the global variables, but as additional characteristic it contains the date of the last determination.

Results Result Result variables are only known with their numeric values in the current method.

Averages Average Value The average value of a variable used in a method. Typical use is the calculation of the average value of a titer use. Thus, a result „Individual Titer“ will be calculated, then the variable Titer will be stored as Average of this result.

Standard deviation

Standard deviation Calculation of the standard deviation as basic population according to the formula:

Calculations of the equivalence points are available as calculations for:

S-shaped titration curves Conductibility curves Photometric titration curves

With the equivalence points it is possible to calculate up to five EQs, depending on the value with the general settings of a formula.

The following issues can be used with functions:

Bracket open Bracket closed Root extracted from a positive number The natural logarithm The exponential function e to the power of a number X at Y calculates the x-value (normally the titration volume) for a particular measuring value.

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4.3. Calculation of a Result 4.3.6. Creation of a Formula

For the operators the three basic arithmetic operations are available and a number of relational operators. Normally, the relational operators will be used in an “If“-statement. E.g. a titration is to take place if a particular measuring value is smaller or bigger than a reference value.

The steepness and the zero point of an electrode will not be documented automatically. It is though possible to define a result with the name „Slope“ and to use the variable Steepness in there. The same is possible with the zero point of the electrode used.

The example shows a formula for the calculation of the chloride content in %. Here the following issues mean:

EQ[1] An equivalence point selected, with many the first. 35,45 Atomic weight of the chlorine 0,1 Molarity of the silver nitrate solvent, of the titration reagent. 100 Conversion in % / Fraction stroke Amount Sample amount 1000 Conversion from g into mg () The brackets

The usual mathematical calculation rules apply. Thus, the, for instance, the omission of brackets would mean that the expression will previously be divided by the sample amount and the obtained value will be multiplied by 1000 resulting in another outcome. The values within a formula can be entered “Manually“ or selected from the menus. Usually, it is advisable to enter the numerical values manually and to choose the variables from the menus.

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4.3. Calculation of a Result 4.3.7. Calculation Average Value and Standard Deviation

The variables will always be selected from the menus of the formula editor. In this formula this is the EQ and the sample amount, also called Amount. The sample amount can mean a weighted sample or even a sample volume. In a sample list a weighted sample can be entered manually or can automatically be transferred by a connected weighting machine.

The variables are visible in the sample list. They will automatically be listed, but can also be configured whether they are to be represented. If a result is called “EQ in ml“, the same designation is used in the sample list, but it can also be renamed and another name can be used.

Multiple typical formulas can be differentiated:

Blank values: Blank value (as global variable) = End value [ml]. The blank value will be saved in a global variable, in order to ensure that it will be available for other methods. Calculated results: Such as the chloride content in %: (as result variable) = EQ1 (in ml) *

molar weight * Molarity of the titration solvent * titer * 100 / (1000 * weighted sample). The titer can be taken from the variables of the reagents, but it must be considered that the value will either be determined automatically prior to the use or that it has been entered respectively. Titer: With a titer the EQ is in the denominator and the weighted sample in the numerator.

Then, a formula might be: Titer (of a reagent) = (weighted sample in g * 1000) / (EQ in ml * molar weight in g * Molarity of the solvent)

4.3.7. Calculation Average Value and Standard Deviation The average value can only be determined from already calculated results or variables. Results and variables available in a method will be shown if the average value or averages will be clicked on via the menu item „Values“. The calculation will only be carried out if multiple identical sample designations have been entered in a sample list of a method. If three identical sample designations are listed in a work list, the average value will be determined out of these three samples. However, a space character or even an addition “a“, “b“ or even “1“, “2“ might be enough to make the sample designation different for the software. A clear differentiation is always possible by different titration times.

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4.3. Calculation of a Result 4.3.7. Calculation Average Value and Standard Deviation

The average value will be represented in the formula editor as „Avg[variable or result].

The associated standard deviation will be obtained via the selection of “Standard deviation“ under the menu item “Values“. In the same way all results and variables available will be shown. Normally, a previously calculated average value will be selected. The representation and designation in the formula editor is “StdDev“

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4.3. Calculation of a Result 4.3.8. Calculation with Sample Variables and Input Variables

The often used term “Relative standard deviation“, short RSD, will be calculated according to: RSD = Standard Deviation * 100 / Average Value In the following example the relative standard deviation of a previously calculated average value of the chloride content will be determined. The average value of the chloride content is saved in the variable 34, in the variable 32 the individual chloride content.

4.3.8. Calculation with Sample Variables and Input Variables TitriSoft allows the input of values for samples in two different ways. It will be distinguished between the “Sample Variables“, short “Sample Data“, which will be entered prior to a titration, and the „Input Variables“, which will be entered during a titration. Normally, both types of variables contain numbers, but can also contain texts under certain circumstances, in order to enter e.g. comments or observations. Here, an entered text must not be confirmed with <ENTER>. A sample variable will be marked as Sample Data on the left side of the listed variables and then created via the menu item “Items“ and “New“. With the menu item “Delete“ the variable can again be deleted.

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The characteristics of a sample variable are:

The numerical value An upper limit A lower limit

With the exceeding or the undershooting of a limit the value of the sample variable will be highlighted in yellow.

A sample variable must be added manually in the titrations-center in the sample list in the register card “Properties“. For this, via the menu item „Properties“ the menu item “Add sample data“ will be selected. A marked sample variable can again be deleted via “Delete sample data“ from the sample list (not as variable).

For the representation in the sample list the variable can be provided with another name via “Title“. Moreover, it can be chosen whether the sample variable is to be included in the screen representation, in the “Sample list“, in the tabular chart and/or in the text export.

The sample variable appears with the preset value in the sample list. The preset value can be exceeded. If the defined limit will here be exceeded or fallen short of, the variables will be marked in yellow. However, it is though possible to work on with this variables, all calculations will be carried out with the entered value.

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The input variable will only be defined in the analysis flow. Further settings in the titrations-center are not necessary. In the methods-center the method will be marked and the modules of the method will be represented with the register card “Analysis flow“. If a weighted sample can only be determined by return weightings of the empty titration vessel, the input variable will be entered after the titration, but prior to the calculation formula. At this place in the flow of the method or analysis a window will pop-up, in which the numerical value will be entered. Comments are also possible if the entry is not confirmed with <ENTER>.

The input field consists of a screen message and a variable in which the input will be saved. A result variable can newly be created or an other, already existing type of variable can be selected. In this example the result variable “Back weight“ will be newly created.

In order to use this value further on, a formula must be created in which this variable will be used. In the following example only the result variable “Back weight“ will be called-up in the formula. In the case of practical methods, a formula with the usage of the value e.g. as weighted sample would be listed here. As all result variables the value will automatically be represented in the sample list and will also be documented in the data base.

4.3. Calculation of a Result

In this example in the sample list the “Back Weight“ appears as column. If a method has been started, then the status appears as “Active“ and at the defined place in the analysis flow an input box appears with the entered comment and the possibility to carry out the necessary entry. At the end of the analysis flow the entry as well as all other results will be shown in the sample list.

In the database the entry is saved independent from any further operations.

A comment will be saved in the database in the same way.

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4.3. Calculation of a Result

4.3.9. Calculation for ISE Calibration and Measurement Ionic-sensitive electrodes (ISE) allow both titration and direct measurement ort he standard addition method. Here, the conditions are different according to electrode and user. With the Direct Measurement an ISE will firstly be calibrated. Practical usage or even different designs – with or without inbuilt reference electrode – will not be described here. The calibration will be carried out with Standards, which will be brought to a possibly constant ionic strength with exactly known concentration by means of TISAB (Total ionic strength adjustment buffer) or ISA (ionic strength adjustment). Any desired number of standards or buffer can be used, which, in practice, often differ in terms of the concentration by one decimal power. This is not imperative for TitriSoft, here also other concentrations are selectable. Then, the measurement is carried out from low to high concentrations in order to avoid a contamination of the low concentrated standards. However, it must be considered that with low concentrations the set-up time of the electrodes increases and can result in ranges of minutes. In TitriSoft an ISE-electrode will be defined like a variable. The electrode will newly added by marking “Electrodes” on the left side of the screen and an electrode will be added as new item.

An electrode should be provided with a name that clearly specifying its characteristics.

The characteristics of an ISE are:

Name Date and time of the last calibration Temperature of the last calibration The four coefficients that define a polynom of the third degree which will be calculated from

the calibration data. If less than four measuring values have been recorded, the number of coefficients will reduce. The determined correlation coefficient of the compensating polynom. The number of standards or buffers will be buffered when the ISE calibration will be used

with the sample changer. The number of places after the comma for the documentation.

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4.3. Calculation of a Result 4.3.9. Calculation for ISE Calibration and Measurement

A method will at least be made up of two modules with ISE calibration. The modules for the calibration are to be selected from the menu “Operation”. Between the modules a screen message will be inserted from the menu “Utils” in order to change the standard. The sequence will be as follows (exemplary):

Electrode will be dipped into the standard with the lowest concentration, the method will be started. The first mV-measuring value will be recorded until the criteria for a stable measuring value are fulfilled. A screen message will be shown so that the user can rinse the electrode and can dip it into

the next standard. The electrode will be dipped into the next standard.

This order will be carried out as long as all standards have been measured.

On the one hand, the characteristics of an ISE-calibration are the characteristics of each measuring value with regard to the drift:

The standard parameters for fast, normal and exact, or in this case, better Measuring interval for drift control Drift criterion in mV/min Minimum delay time Maximum delay time

Additionally, there are special characteristics for the ISE calibration measuring value: Name of the electrode, with which it will be measured and for whose name the calibration

values will later on be saved.

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The concentration of the standard or buffer in mol/l or even in another concentration unit such as mg/l. However, these must be standardized in calibration and measurement. Name of the result in which the V-value will later be saved for this concentration.

In the example below the actual concentration is saved via “Buffer” and in Result “c= 0,00005” the mV-measuring value will be saved for this buffer.

In the following example it is calibrated with three standards, depending on the measurement a message “Next standard” appears.

The concentration in the first standard was 5 * 10 -6mol/l, the one of the following is 5 * 10 -5mol/l and the one of the last 5 * 10 -4mol/l.

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In the following sample list a calibration of a fluoride-electrode will be carried out in the first position and in the following positions a control-measurement with these standards.

The sample list shows for every measured standard the determined mV-measuring value and for every ISE measurement, basing on this calibration, the determined concentration. The strong dependency on very precise mV-measuring values is obviously. The measuring values can certainly be improved by more exact drift movements.

For the ISE- measurement the last saved measuring values of the ISE-calibration with the selected electrode will be used. Besides the common characteristics for a measuring value, in this case the same as with the calibration, the following characteristics will be added:

Variable type Name of variables, in which the calculated concentration-result is to be saved. Name of variables, which can be selected from a list showing the electrodes available. Number of decimal places for the result in mol/l or the unit that was used with the calibration. mV instead of concentration offers the possibility to show the measuring value instead the

calculated concentration.

If the calculated result will be represented, the associated measuring value should additionally be documented in a formula as end value in mV.

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4.4. Examples of Methods 4.4.1. Dynamic Acid-Base Titration Hydrochloric Acid/Sodium Hydroxide Solution

4.4. Examples of Methods In the following, some examples will be specified that are to support own methods. Some methods can be used for other purposes and, thus, not all settings can be transferred into own applications without checking having them checked. Furthermore, electrode-characteristics can differ from each other and can cause a modification of parameters. A guarantee that desired results can be achieved with the parameters here specified is not given.

4.4.1. Dynamic Acid-Base Titration Hydrochloric Acid/Sodium Hydroxide Solution The dynamic titration, in this case acid/Base titration, is the most important method for the determination of exact analytical amounts. The equivalent realization will exactly be calculated by the inflection point of the titration curve. Thus, it is important to have the step length as small as possible without having the curve noisy. This can easily be recognized in the first derivation in the form of teeth. Such teeth can cause a wrong detection of the equivalence point. Good and fast electrodes in combination with a titration that is not too fast and professional stirring will normally lead to optimum results. The settings for this example of the dynamic titration are:

Selection of the titrator the electrode is connected to, in this case a TitroLine alpha plus with the address 1 and a pH-electrode connected to measuring input A. The tape of titration is dynamic. The stirring speed will only be supported in the case of a sample changer, but not directly at

the TL alpha plus. The reagent will be dosed by TL alpha plus, the dosage top section with the sodium

hydroxide solution is located there. The reagent will be selected from a list or newly entered, in this case 0,1 mol/l NaOH The top section will be filled after the titration so that it can easily be exchanged with another

one after the titration, if necessary. This issue is particularly important in the case of multiple titration modules in one method. The titration should end at a particular pH-value in order to guarantee that it is not over-

titrated. Without a marking in this field a possibly entered measuring value will not be analyzed as end criterion. The pH-value the titration is to stop at will be entered here. In case of titrations with 0,1 mol/l

NaOH in watery systems usually all titration steps will have been carried out. As security criterion the consumption will be set to 25 ml, so that the tumbler will overrun and

will stop even with a defective electrode ort hat the method will be ended even with an empty reagent bottle. The titration should stop after the first EQ. This criterion can cause an early abortion with

some applications. Thus, the example of the following titration curves has been carried out without this EQ-criterion. This will be specified with the titration curves. The calculation of the step length is carried out dynamically with the settings for a steeply

rising titration curve. The titration will be carried out fast. Usually, such a titration takes approx. three minutes.

However, if the curve shape causes many small titration steps, the titration can take significantly longer.

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4.4. Examples of Methods 4.4.1. Dynamic Acid-Base Titration Hydrochloric Acid/Sodium Hydroxide Solution

The titration graphic shows the ml-values of the titration agent on the x-axis and on the dependable y-axis the pH-values. A second y-axis is not defined here.

At first glance, the titration curve shows the expected course. A strong step of the blue pH-curve leads to a small peak or maximum in the first derivation, the equivalence point will be set appropriately in the steep part of the titration curve. Or is it not? The pH-value is with pH 7,82 somehow far away from the expected neutral point of pH 7.

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4.4. Examples of Methods 4.4.2. Dynamic Acid-Base Titration Phosphoric Acid / Sodium Hydroxide Solution

By zooming out it becomes apparent that the step consists of two parts. This is a common problem with acid/base-titrations and shows clearly the existence of carbonate in the titration agent or in the water. A titration that was slightly slower would work out the first step even in a more significant way and, with slightly smaller steps, the carbonate content could even be determined quantitatively.

4.4.2. Dynamic Acid-Base Titration Phosphoric Acid / Sodium Hydroxide Solution The phosphoric acid is a three-basic acid, for which the first both equivalence points will be recorded in watery solutions. The pKs-value of the third proton is as large that it can not be titrated in water. With applications for the determination of phosphate the content can be determined as difference of both equivalence points. This method requires that no metal hydroxide or other acids are existent in the pKs-range of pH 6 to pH 10.

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4.4. Examples of Methods 4.4.2. Dynamic Acid-Base Titration Phosphoric Acid / Sodium Hydroxide Solution

In this example the dynamic titration was also be used. Unlike the previous example it will be worked with 0,5 instead with 0,1 molar NaOH. But this depends only on the concentration of the sample. The titration ends also at pH 10,5 or maximal at 25 ml, depending on which criterion will be fulfilled at first. The dynamic parameters will be set manually. As significant characteristic the common minimal step length had been increased to 0,05 ml, in order to carry out a certain chemical smoothing. The biggest step length was reduced to 0,5 ml. The dynamic parameter have been determined with a = 2,7 and b = 0,9, as described in the chapter on Dynamics.

The method contains three formulas, in the first and second both equivalence points will be determined. Here, the determination of analysis windows can be necessary in certain cases. In this example the first EQ would lie between pH 3,5 and 7 and the second pH between pH 7 and pH 10. The limits can also be specified smaller or narrower, but then there is the risk that for an EQ there are not enough data points available. Then, in a third formula the difference of both EQs as (EQ[2] –EQ[1]) will be calculated.

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4.4. Examples of Methods 4.4.4. Acid/Base Capacity

The titration graphic shows both well-titrated steps with the correctly set equivalence points. In the steps the smallest step length will be reached, there is also no noise. The largest step length of 0,5 ml will again (scarcely) not be reached after the first step, here it is possible to optimize the dynamic parameter a little more.

4.4.4. Acid/Base Capacity A typical application with drinking water and waste water is the determination of the acid and base capacity. This is a titration of often 100 ml water with 0,1 molar hydrochloric acid up to an end point of 4,3 for the KS 4,3 value.

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The titration will be carried out as end point titration. The last titration steps from a pH of 4,7 will be titrated with 0,01 ml-steps. Too small steps cause a sluggish end, too large steps are imprecise. The method is made up with the following modules:

The individual parameters are:

The overview on the method:

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The sample list will be configured automatically if the method will be selected. In this example only the user was removed from the chart view.

The printout is often printed with the figure of the titration curve of multiple results as curve list on one page.

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In the database the results will automatically be saved and can newly be documented at any time.


Depending on the characteristics of the water and the electrodes, the curve shape differentiates. The represented titration curve was titrated with an old and sluggish electrode, otherwise the titration curve would look smoother and more even. A slower titration would improve this curve. Since only the end point will be analyzed, this is not so important in this case.

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4.4. Examples of Methods 4.4.5. Chloride Titration

In the data list it is obvious that the last titration steps have been carried out with small 0,01 additions in order to guarantee an exact result.

4.4.5. Chloride Titration The chloride titration is a very common application in all areas, be it chemistry, pharma or food. The titration is a precipitant titration and must not be carried out too fast. On the other hand, it is so precise that it can be used as inspection method for the right volume of burets according to ISO 8655 part 7. The titration is usually working very well if it is worked carefully and, in some cases, some tricks will be applied:

The sample must be acidified, with sulphuric acid or nitric acid. The amount depends on the application. The smallest step length must not be too small, from 0,5% of the total volume. The titration must not be too fast, approx. 3 to 5 minutes or slower. In many cases the addition of tenside is helpful (not chloride-containing) or polyvinylalcohol that

the electrode will less pollute and to achieve better curves. The titration will be carried out dynamically if the content and the consumption are not too small.

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4.4. Examples of Methods 4.4.5. Chloride Titration

Besides the actual, calculated result, also the equivalence point will often be documented, so that it can directly be judged if it has been set properly. Average value and relative standard deviation will also be implemented with a multiple determination.

The formula has already been described with the formula creation.

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4.4. Examples of Methods 4.4.6. Redoxtitration Titration with Thiosulfate

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The represented titration curve shows a smooth course. This becomes clearer in the representation of the first derivation (in red). With a noisy titration curve many teeth would often be visible. But this would impact the security of analysis and the precision. For the depicted titration the electrode AgCl 62 was used.

4.4.6. Redoxtitration Titration with Thiosulfate The jodometric applications often base on a back-titration with thiosulfate. The titration will be indicated with a platinum electrode (in this example a Pt 62). The titration will be carried out dynamically and shows a strongly decreasing curve flow. End criteria can be number of equivalence points, potential or even consumption. In the following figure the titration parameters will be. The tirtation will usually be carried out in sulphuric solution. As original titer e.g. bichromate can be used.


In this example the titration curve shows an ideal dynamic curve progression. It will be titrated with 1 ml steps as largest step length, as smallest step length it will dynamically be controlled downwards to 0,01 ml steps. Thus, the titration is comparatively fast and precise. The steep and sharp first derivation (in red) makes this clear.

The list of the measuring points shows that a precise titration does not necessarily need many measuring points. In the steep step range it will be titrated with the smallest step length, the transitions are continuous and fluent.

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The green curve in the following representation shows the time response. The entire titration has taken approx. 190 seconds. Ca. half of the time was needed for the exact titration in the equivalence point range. With the fast titration a pre-titration is not necessary in the first part. A stop criterion in this case would certainly have accelerated the titration, but would not have made clear the complete titration process in this example. If the stop criteria equivalence point would have been used with this titration, the titration had lasted approx. 150 seconds.

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4.4. Examples of Methods 4.4.8. TAN in Oil

4.4.8. TAN in Oil The titration in oils with glass electrodes is a difficult application. There are hardly any protons available and the glass electrode is limited in its usability. Here, the TBN-titration with perchlor acid is described. According to the same scheme and with the same parameters the TAN application which is often even more difficult will be carried out. In order to guarantee that the titration shows reproducible results, the following rules must be adhered to:

It will be titrated linear with step length that are not too small. The following rule applies: Not more than 50 measuring values. If the titration curve is not reproducible in its form, the step length will be increased. This is commonly known as „chemical smoothing“. The titration will be carried out slowly. Fixed delay times of 15 seconds or longer are usual for

one measuring value. In this example it will be worked between 10 and 20 seconds in a drift-controlled mode. Often, it will be titrated with a (as specified in the norm) final consumption of 4 or 5 ml. The

sample amount will be adapted to the expected consumption. After every titration the electrode must be conditioned and cleaned carefully. The measuring amplifier of the titrator will be adapted with a damping adjustment for the titration

in solvents with small dielectricity constants. Without appropriate cleaning and conditioning the glass electrode shows irreproducible titration curves after a short while. Therefore, the following scheme will strictly be recommended:

Cleaning one minute (even longer) in the clean solvent of the sample. Conditioning for one minute in water Second cleaning step in clean solvent (the same as with titration)

The sequence of the titration will be shown in the following figure.

The titration parameters are visible in the next figure. The linear titration with steps that are not too small and long delay times between these steps is important.

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A titer position, here in chlorobenzene, shows the good reproducibility with right titration parameters.

The two following titration curves show a sample titration and a blank value titration. Typical is the wide first derivation due to the large step length. Since the equivalence point will be determined by an approximation according to the method of least error squares between the measuring values, the calculation is very precise despite the large step length. Under these circumstances blank value titration can be a special challenge. In this example it was slowly titrated with 0,004 ml step to 0,1 ml (!). The blank value can be determined properly. If this is not possible a manual analysis of the titration curve or even a titration up to a particular mV value determined by experiment is advisable.

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4.4. Examples of Methods 4.4.10. Direct Measurement Fluoride and Calibration

4.4.10. Direct Measurement Fluoride and Calibration The direct measurement with a fluoride electrode is a reliable method especially in matrices that are not too complex. The fluoride electrode has a good selectivity, better than most other electrodes, except the glass electrode. The measurement is carried out by means of the equation of Nernst:

d

Ox

aa

FnTREE

Re0 ln

**

+=

The equation is simplified due to the use of the common logarithm to the following equation:

d

Ox

aa

nEE

Re0 log05916,0

+=

This means a theoretical slope of 59,16 mV for monovalent ions. In practice, the logarithm of activity will be plotted towards the potential:

log a

mV The real slopes and zero points often differ significantly from ideal values. The theoretical slope with monovalent ions should amount to 59,16 mV per decimal power mol/l activity, with bivalent ions 29,58 mV. A calibration is thus not implicitly necessary. Since the potentials obtained via the equation of Nernst contain only a statement on activities and no statement on the concentration, the ionic strength must be kept constant. Moreover, the conditions of the calibration and of the measurement must not, or even slightly, differ from each other in the sample. Thus, in practice it will be worked with exactly adjusted pH values and with ionic buffers.

log a2log a1

mV2 P2

P1 mV mV1

log a

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If a straight line is basis for the calculation, its parameters slope a and zero point b will be calculated according to:

bxay += * For the calibration with the two points P1(x1,y1) and P2(x2,y2) it follows:

1log2log12aa

mVmVa−−

=

1log*1 aamVb −=

The logarithm activity of the sample can be obtained via a measuring value in the same matrix from the calibration straight line.

abobemVobea −

=)(Pr)(Prlog

The concentration is:

10 )(Prlog)(Pr obeaobec = With calculation via natural logarithm:

exp )(Pr*log3026,2)(Pr

obeaobec =

The following chart shows the values of a calibration. In the first column there are the concentrations of the standards and the measured mV values in the second. In the third column are the calculated logarithms of the concentrations that will be inserted into the graphic.

C [mol/l] mV log c 0,000005 165,4 -5,301030010,000050 109,7 -4,301030010,000500 49,0 -3,301029980,005000 -10,5 -2,301030010,050000 -51,3 -1,30102999

In the following graphic the logarithms of the concentrations are depicted on the x-axis and the measured mV values on the y-axis. A linear (or with TitriSoft a nonlinear) compensating equation produces an equation from which the concentrations can be calculated if a measurement of an unknown sample is carried out. In order to keep the difference between the concentration and the measured activity as small as possible, a TISAB (Total Ionic Strength Adjustment Buffer) solution will be added to the sample. This solution ensures a preferably constant ionic strength and provides a nearly stable pH-value.

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Calibration Fluoride-Electrode

y = -55,375x - 130,35R2 = 0,9959

-100,0

-50,0

0,0

50,0

100,0

150,0

200,0

250,0

-8 -6 -4 -2 0

Log c [mol/l]

Mes

swer

t [m

V]

In TitriSoft a calibration will made up in a method. Here, the basic procedure for a method with a sample changer or without sample changer differ. In the following the procedure with the sample changer will be described. For every standard used a calibration module will be inserted into the procedure. Between the calibration modules is a screen message that indicates the next standard enabling a change of the solutions.

In the settings for the individual measuring values it is recommended to work with drift control. The measurement takes the longer, the more diluted the standards, or later the samples, are. In this example the electrode has between 30 and 60 seconds time to adjust itself. These values should be extended for a measurement that must be very precisely. Subsequently, the electrode will be selected or, if no electrode is existent yet, created, i.e. a name for an electrode will be entered. Then, the concentration of the standard will be entered in mol/l. For the result, an mV measuring value, a name will be used that later on allows a secure allocation, in this example the designation of the concentration used.

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Between the calibration modules a screen message has been built in, in order to ensure that the standard can be changed for the electrode. Usually the first step is to use the diluted standards firstly and, as a second step, to change to the more concentrated. To rinse the electrode is thus not necessary.

The individual calibration modules differ by means of the stated concentration of the standard and the adjusted name.

The concentration always changes by one decimal power.

The finished sample list shows the measured mV value for each standard.

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The values can be depicted in the graphic and the linearity can be checked optically.

The measurement of a sample will then be carried out with a method that contains the module ISE-measurement. The module contains at first the parameters for the drift settings of the electrode. In this case they comply with the settings for the calibration. In the second part, the settings for the calculation, a name will be entered for the calculated concentration, the electrode will be selected (certainly the one that was previously calibrated..) and the number of the decimal places will be specified. With concentrations expected to be small sufficient places must be defined! In an additional setting it is possible to define if the mV value is to be represented instead the calculated concentration.

The mV-value will usually be documented with an additional formula by representing the end value mV with a decimal place in a formula.

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The following figure shows in a sample list a calibration and two sample measurements. The number of places will not be represented properly. In this case two of the standards were measured as sample, the theoretical target values should be 5 * 106 5 * 105 mol/l.

The calibration can also take place in mg/liter, the results would then have the unit mg/liter.

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5. Titrations Center In the titrations-center the titrations will be carried out. Every work process with the devices takes place here. From the navigator the titrations-center will be reached by clicking onto the graphic or onto the large push button „Titrations Center“.

In the overview „Overview“ all four configurations that are simultaneously possible will be shown with their titration graphics currently running. On the left side one of these configurations can be selected. Normally, only one configuration is available, a selection is then not necessary or possible. If the configuration has been marked on the left screen side, direct functions of the connected hardware are available.

Menu item Titrator:

Represent measuring points: It will be switched between the representation of the points of the On-Line-Titrations curve and the line representation. Normally, the point representation shows the individual titration steps in a clearer way and is, thus, particularly advisable for the method development. Switch on/off stirrer: A connected controllable stirrer, e.g. at the sample changer, can be

adjusted. Calibration: A connected TR 250 can and must be calibrated here. A TL Alpha or Alpha plus

will always be calibrated at the titrator.

Menu item sample changer:

Bring down titration head: The titration head of the sample changer will be brought down up to the lower sensor. If no tumbler stands in this position, the head does not come down. However, the sensor be covered for test purposes. For routine operations this procedure is though not recommended. Percentage numbers that have possibly been set previously for the bringing down of the titration head do not have validity with this menu item. Lift titration head: The titration head of the sample changer will be lifted up to the next head

sensor. Bring down titration head (COD): The titration head of the sample changer will be brought

down up to the position of the COD-vessels. If no tumbler stands in this position, the head does not come down. However, the sensor be covered for test purposes. For routine operations this procedure is though not recommended. Next position: The plate moves to the right up to the next position.

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If the configuration is marked on the left side of the screen, the two register cards „Configuration“ and „Work list“ are available. Via „Configuration“ the current On-Line-Titration curve will be shown. If there is not titration currently running, this field will be empty. The other register card shows all work lists available.

The work lists will be shown in table form, their names can be changed if the respective number is marked. The following characteristics are available:

Name TL alpha method yes/no: With TL alpha method the Karl-Fischer data and results will be

taken over into TitriSoft. Changeable, in part changeable or not changeable Sample changer yes/no. A sample changer can not be configured in a work list i fit is not

marked here. On the left side all existent work lists are listed. They show a plus sign. If this has been clicked on with the mouse, all samples will be shown in this work list and the plus sign changes into a minus sign.

A new work list will be created by marking the configuration and the selection of the register card „Work list“. Now, the menu „Work list“ is available. The following processes are possible:

To created new work lists To import work lists, a file selection window will be shown by showing all work list data and

the possibility to select one particular file. To export marked work lists. To delete work lists.

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The sample list is the center of all practical work procedures with TitriSoft. It represents the samples to be titrated or already titrated in a table form in individual lines. The columns show the characteristics that are to be represented. By means of the register card „Settings “ the following issues can be processed;

The limits of the weighted samples can be determined. The type of the documentation and result output can be defined. A connected sample changer can be configured.

With the register card „Properties“ the characteristics of the columns will be defined. These characteristics are: which of these characteristics are to be seen and who are the titles named. Additional variables can be visualized.

In the menu item „Sample list“ the samples will:

Newly added into the sample list (this function has the button „INSERT“ on the PC keyboard) Be reset in the sample list, i.e. the status will be reset from „aborted“ or „ready“ to „Planned“ In a sample list all samples of this sample list will be reset into the status „Planned“.

Samples can be marked and moved to another person and, there, they can be inserted. However, they will be processed in the order of their numbers. Via the menu item „Renumber list“ the positions can again be renumbered from the beginning to the end in ascending order. A work list can completely be exported into an Excel-file. The appearance will completely comply with the appearance in the work list. Additionally, the export of a text file is possible if this has been configured under “Settings“. Samples in a work list can also be deleted, contrary to titration results. Thereby, sample information will not get lost since all finished titrations will automatically be saved in the data base.

With a printout of a sample list there is the table form and the report. “Print sample list“ prints the table in the form in which is it represented on the screen. The report can be configured on the register card “Settings“. There the output forms that contain titration curves are also available.

The content of the pdf-files complies entirely with the print-output, the output will automatically be carried out into the TitriSoft-directory „\PDF\Methods“.

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5.1. Creation and Modification of a Work List 5.1.1. Creation of a Work List

If on the left side of the screen it will be clicked on the plus-sign of a work list, the individual samples will pop up. The sample designations will be shown.

5.1. Creation and Modification of a Work List A work list is not protected like a method. The work list has no influence on the analysis result, parameters to be entered such as the weighted sample will documented automatically and not disengageable. Thus, they become entirely traceable. In this way, a work list can be created and edited by everyone who has the respective authorization. The term „Sample list“ is a sub-term of the „Work list“ that additionally contains all configuration possibilities.

5.1.1. Creation of a Work List A work list can be created if the configuration is marked on the left side of the screen under the register card „Work list“.

Via the menu item “Work list“ the following menu items are available:

New: Creates a new work list. Import: Imports a TitriSoft work list; however, the function contains not the methods and

variables that are used in the work list. But the sample results are contained without graphics. Export: Exports a TitriSoft work list; however, the function contains not the methods and

variables that are used in the work list. But the sample results are contained without graphics. Delete: Deletes a work list. The deletion refers only to the work environment and has no

influence on the analysis results and, thus, a deletion is possible.

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5.1. Creation and Modification of a Work List

The following characteristics of a work list will be set with a creation:

Characteristics Meaning Name work list The name of the work list should represent which kind of samples are to

be titrated with this list. Due to the fact that the name will be used at the export and with the creation of pdf-files as file name, it should not contain any special signs that are not allowed to be used in a file name.

TL alpha method A marking as TL alpha method means that after the start of the work list it is only allowed to take over Karl-Fischer data from a TL alpha plus. All inputs such as sample designation and weighted samples will be carried out at the TL alpha plus. The results and the titration curves will be taken over into the TitriSoft data base after the titration. The data transfer takes approx. one minute. In the meantime it is not possible to start a new method at the TL alpha.

Type list The type of a list can reach from changeable to not changeable. In the current version of TitriSoft this function will not be supported anymore and the menu item is only still available in the software due to data compatibility.

With sample changer Only if a marking has been carried out here, a sample changer can be configured via these settings. However, sample changer must have been detected in the configuration.

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5.1. Creation and Modification of a Work List

5.1.2. Add and Delete Samples If a sample list has been created, it will be marked on the left side of the screen. On the right side an empty chart will appear. Only the head of this chart is partially to be seen.

Via the menu item “Sample list“ and via “New sample“ it is now possible to insert as many samples into the sample list as it is typical for the work process. If on one day 10 samples of a particular type will be processed, the work list should contain these 10 samples. With a 16fold sample plate and three rinse positions 13 positions will be empty. A sample list should then contain 13 positions. The samples can also be inserted with the <INSERT>-button on the PC keyboard.

In the next step the field “Analysis“ will be marked in every position. A small black triangle appears. If it is clicked on it with the mouse, all methods available will be listed. The method will be selected. Automatically, all variables will be shown, normally the results. All inserted samples have the status “Planned“.

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5.1. Creation and Modification of a Work List 5.1.3. Delete Work Lists

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Samples can also be deleted if they are marked individually or in groups and if the menu item “Sample list“ – “Delete Sample “ has been activated via mouse or keyboard.

5.1.3. Delete Work Lists Complete work lists can be deleted by marking the configuration on the left screen side and by marking this work list on the right side which is to be deleted. Via the menu item “Worklist“ “Delete“ the marked work list can be deleted.

Via the menu item “Work list“ “Delete“ the marked work list can be deleted. A deleted sample list is irrevocably deleted and can not be brought back. It is recommended to previously backup the entire database or, at least, to export a work list and, thus, to carry out a backup of this work list.

5.1. Creation and Modification of a Work List 5.1.4. Configuration of a Work List

5.1.4. Configuration of a Work List Via “Settings“ the following characteristics can be configured:

Balance limits Documentation Sample changer

The double arrows can be clicked on with the mouse will then pop up. The properties of these three ranges will then be visualized.

For weighted samples it is possible to define the smallest and the largest sample amount to be weighted via “Balance settings“. The sample amount can be limited by e.g. norms but also by end criteria in the case of titration parameters. If e.g. a maximum consumption is defined for the titration, it automatically limits the maximum sample to be weighted since otherwise the titration end would not be reached. If a sample weight is outside the limits, it will be marked in yellow in the sample list and will thus be very striking. However, in every case the titration can though be carried out even if the weighted sample is outside the limits.

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The documentation will be determined via “Setting Output“:

Menu item Meaning Form of the output The form of the output offers the following possibilities:

The list can be printed in portrait or landscape format, as defined in „Properties“. A curve list contains all sample information that are defined in “Properties“ including a small titration graphic. An individual sample contains a large graphic including all sample information.

Self-defined printout It is possible to insert own logos into the output. This is to be carried out via the own editor. For this editor Schott Instruments does not provide a documentation. The use is at one’s own risk.

File name for output If the self defined printout will be used, the form must be saved as file. This will happen within the form editor.

Title for output The printout can be provided with an own title, which is to be defined here.

Print automatically At the end of the sample list the automatic printout can be started. It can also be started manually via a menu item.

Export at the end of the work list.

With a finished sample list it is possible to automatically create an export file. Here, it will be defined if there should be such an export.

Export csv-file A csv-file will be defined that will always be overwritten anew with every start of the work list. If it is to be taken over into Excel or into a LIMS program, this is to happen prior to the new start of the sample list.

If a sample changer is to be used in a work list, at first a marking must have been carried out in the respective field during the creation of the sample list. Additionally, the sample changer must have been detected with the automatic detection of the hardware components.

The following settings are available for the sample changer:

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Menu item Meaning

Number of positions The sample changer can have the following number of samples, which must be set in the following form:

12 16 24 30 36 48 60

Skip empty positions If a position is empty, there are two possibilities: The position is to be skipped The sample changer should stop and wait

When this point is marked the position will be skipped. The status of the sample will be set to „Skipped“. This is the recommended setting. The detection is carried out via a sensor that works in the near IR-area so that it is usually not affected by daylight.

Continue with first position if work list finished

If the ready titrated samples will be removed from the plate and they are to be exchanged by new samples, it is possible to continue to titrate with the first sample. In this case, the sample list contains more samples that positions available on the plate.

Type of rinsing The rinsing can take place in two different ways, by a number of rinsing positions or via a connected pump with which the electrodes and titration tops will be washed. The pump will be inserted together with a titration head which is provided with a splash guard. Empty positions in the titration head will be closed with a blind plug. The cleaning nozzle with fixation attached in the center of the titration head. On the plate there are up to three positions available for the rinsing in rinsing positions. These positions are automatically the last positions on the table. With applications in organic solvents the positions will be used to condition and clean the electrode after each titration in the solvent (approx. one minute each), then in water or in diluted acid and then lastly again in pure solvent.

Rinsing time The rinsing time is minimum ten seconds for the rinsing positions since a

magnetic stirring staff does hardly start to stir previously. With a pump connected the time is dependent on the quantity of the flushing solution that still fits into the tumbler.

Bringing down the titration head in the rinsing process, rate in %

The titration head can be brought down into any desired interim-position via a timing control. With ground electrodes with normal short length of approx. 9,5 cm the titration head will be brought down by 100%. With longer electrodes or titration tops the height must be adjusted. If 250 ml tumblers large format will be used in the TW alpha plus/16, the titration head can only be brought down by 40 %.

Operation at the end of the work list

At the end of a sample list the titration head can remain in the upper position. However, during the night the diaphragm dries out and the electrode is not directly ready for operation the next morning. As alternative the titration head can be brought down into the first or last position at the end of a work list. Therefore, the first sample will, directly after it was titrated, be removed from the sample plate and exchanged by e.g. a potassium chloride solution. It is also possible that in the last position there is a tumbler with potassium chloride, but normally only when it was not used as rinsing position.

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5.1. Creation and Modification of a Work List 5.1.5. Configuration of Variables

Bringing down the titration head in the titration process, rate in %

The titration head can be brought down into any desired interim-position via a timing control. With ground electrodes with normal short length of approx. 9,5 cm the titration head will be brought down by 100%. With longer electrodes or titration tops the height must be adjusted. If 250 ml tumblers large format will be used in the TW alpha plus/16, the titration head can only be brought down by 40 %.

If the register card „settings“ is marked, the two menu items “Print“ and “Pdf“ are available. Via “Print“ the sample list can be printed as represented on the screen.

In the same form as the printout a Pdf-file will be released into the preset directory “\PDF“ via the menu item “Pdf“.

5.1.5. Configuration of Variables The form of the chart will be determined with the register card “Properties“. In the chart all variables of a method will be listed:

The names of the variables as system variable or as defined in the methods The type of variables; system variables are principally available in a work list. The title as it is to be represented on the screen or with the printout. The marking whether a variable is to be represented in this line on the screen in the sample

list or not. The marking whether a variable is to be represented in this line on the screen in the printout

in table form or not. The marking whether a variable is to be contained in this line on the screen in the exported

csv-file.

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The title can be named differently than the original variable. The following menu items are available:

Properties: Here, the sample variables can be added. These will not be shown automatically. Print: As with the register card „Sample list“ the report or the chart can be printed in the

format depicted on the screen. Pdf: As with the register card „Sample list“ the report or the chart can be released as Pdf-file

in the format depicted on the screen. The output will automatically be carried out into the \PDF-directory of TitriSoft.

The form of the pdf-version looks exactly like the printout-version. With the menu item “Print“ it is not printed instantly, but the print preview will firstly be shown. By means of this “Trick“ it is possible to have a look at the layout of the pdf-file previously.

With the creation of a work list, only the system variables and the results will automatically be represented. Sample variables will manually be added to a work list with the menu item “Properties“ “Add sample variable“ and can there also be deleted with “Delete sample variable“.

Via “Properties“ in the properties-window the sample variable can be selected by clicking onto the triangle in the marked field. If it has not been created yet, here it can be newly entered. Thus means that it is not yet used in a formula. Such variables can then be used as comments. But it is important that the text input will not be confirmed with <Enter>, in order to make sure that no type check will be carried out. Such a check would expect a number at this place.


The following example shows a sample list with a field a sample variable with the name “Comment“, which has been allocated the name “Info“ in the title.

The name of the variable can differ from the name of the title in the sample list. Thus, a variable can be used in many methods. Consequently, this is a more easy way. But to have a name for each sample list that perfectly shows what is to be entered in this field. A marking in one of the fields Sample List, Report or Export means that this variable is to be depicted on the screen, to be printed in the chart or is to be exported at the end of the work list.

In a work list multiple sample variables can be used. In the example below an input variable has been used in the method. This variable will be represented and printed like a result variable.

In the example below „Info!“ was entered into the info field in the sample with the designation „Test Comment“.

The information or the comment will automatically be saved in the data base similar to all other method results.

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5.2. Defining the Documentation 5.2.1. Printout

5.2. Defining the Documentation The documentation refers to the printout which can be generated as a real printout on a printer or as a Pdf-file, or to the export in an Excel-file. The automatic export at the end of a work list is easily importable as csv-file in other programs.

5.2.1. Printout The documentation will be configured via “Settings“ and “Settings Output“.

Menu item Meaning Output format The form of the output offers the following possibilities:

The list can be printed in portrait or landscape format, as defined in „Properties“. A curve list contains all sample information that are defined in “Properties“ including a small titration graphic. An individual sample contains a large graphic including all sample information.

Self-defined printout It is possible to insert own logos into the output. This is to be carried out via the own editor. For this editor Schott Instruments does not provide a documentation. The use is at one’s own risk.

File name for output If the self defined printout will be used, the form must be saved as file. This will happen within the form editor.

Title for output The printout can be provided with an own title, which is to be defined here.

Print automatically At the end of the sample list the automatic printout can be started. It can also be started manually via a menu item.

Export at the end of a work list.

With a finished sample list it is possible to automatically create an export file. Here, it will be defined if there should be such an export.

Export csv-file A csv-file will be defined that will always be overwritten anew with every start of the work list. If it is to be taken over into Excel or into a LIMS program, this is to happen prior to the new start of the sample list.

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The sample list can be printed in portrait or landscape format. The report contains here all information that are marked below Report

The formatting complies with the screen representation.

With the representation of the “Sample list“ all sample information will be printed as list, aside a small graphic of the titration curve. After the sample list and all calculations are finished even calculated equivalence points will be represented. If TitriSoft is left, the representations of the curves are not available anymore.

The “Individual sample with curve“ contains the titration curve below a text field with all sample information. The standard representation after a titration is the titration curve with the equivalence point without first derivation.

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It is possible to define an own head for the documentation. It is possible to embed own corporate designs.

For this, a marking will be made in “Self-defined term“. If now the line “File name for output“ will be marked, three points appear. If these points will be clicked on, the formula editor will be started.

Here only a brief example will be shown on how one own heading line can be sufficient. The description of the designer is part of this instruction. The usage is at one’s own risk. It can not be guaranteed that all desired applications are possible. However, it is to offer the experienced user the possibility to modify their reports according to their wishes after comprehensive and complete tests.

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5.2. Defining the Documentation 5.2.2. Export

If the text field is clicked onto on the left side below the arrow, it is possible to enter an own text which can be formatted with different colors and styles of lettering. In this example the TitriSoft logo has been deleted and a text field (as the one marked beside the text editor) was inserted. The third symbol below the arrow allows the integration of a graphic symbol.

Then, the printout contains an own title with company designations.

5.2.2. Export The export can easily be carried out via as Excel-file. This export can be carried out at any time. Thereby, the file name will be asked for. With this file name an Excel file will be generated with the extension *.xls. This file is identical to the representation in the sample list. The following sample list is to be exported in an Excel-file:

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5.2. Defining the Documentation 5.2.2. Export

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Via the menu item „Sample list“ the menu item “Export Excel“ will be selected.

In the following file-dialogue a file name will be asked for, the ending *.xs will automatically be added.

The numerical fields will not automatically be represented as numerical fields in Excel, thus, they are provided with a respective marking. With conversions there is an automatic conversion process into a number.

At the end of a work list a csv-file can automatically be created. For this, the field “Export csv-file“ will be marked and the dialogue for the file name will be entered.

Below the properties of the work list, the desired fields must also be marked in order to guarantee that information can be written into the file.

5.3. Carry out Titration 5.3.1. Start and Stop Titration

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5.3. Carry out Titration The titrations can only be started via a work list. Without a work list and a sample list a titration or measurement is not possible.

5.3.1. Start and Stop Titration A titration can only be started if the sample has the status “Planned“. By clicking the start symbol above right on the screen the titration or measurement will e started.

A finished sample can be reset, but all result information will get lost in the work list.

It is possible to reset all samples or only the marked one.

A sample which is particularly urgent can be marked with the mouse and be moved to the top position.

5.3. Carry out Titration 5.3.1. Start and Stop Titration

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The sample list can then again be renumbered with the menu item “Renumber list“. However, it must be observed that the positions of the samples on the sample plate comply with the positions in the list. During the titration an On-Line curve of the measuring values will be represented. It will be depicted on the right side of the screen if on the left side the configuration is marked. The online titration curve can be zoomed with the mouse. This is carried out by moving a square downwards to the right with the left mouse button pressed. A respective square upwards to the left restores the original curve. The measuring values will be represented below the titration curve.

The graphic below shows pH-values represented per time.

5.3. Carry out Titration 5.3.2. Work List during Titration

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A titration or measurement can be stopped by clicking with the mouse on the stop-symbol in the upper left part of the screen. Measuring points up to this point in time will be saved in the database, however, calculations will not carried out anymore. The sample obtains the status “Stopped“.

5.3.2. Work List during Titration During the titration an online titration curve will be shown. This curve will be visualized when the configuration name will be clicked on. Via the menu item “Titrator“ “Represent measuring points“ the individual measuring points will be shown and not only the curve. The scaling is carried out automatically. If the scale is not clearly arranged, the table form of the sample list will be clicked-on on the left screen side and subsequently the configuration name. Thus, the graphic will newly be scaled.

5.3.3. Direct Operation with Titrator and Sample Changer In order to work with stirrer and sample changer, the configuration name will be marked on the left screen side. Both menu items “Titrator“ and “Sample changer“ are available.

5.3. Carry out Titration 5.3.3. Direct Operation with Titrator and Sample Changer

With the menu point “Titrator“ “Switch on/off stirrer“ a stirrer of the sample changer or of the TL alpha (but not TL alpha plus) can be switched on or off. One further menu item is the calibration with a TR 250, which will be started here.

Via the menu item “Sample changer“ the following menu items are available:

Lift titration head: The titration head will be moved into the upper position. Bring down titration head: The titration head will be brought down by 100% if a tumbler

stands in the position. Bring down titration head (COD): The titration head will be brought down to the height of the

COD vessels. For this, the titration head must be brought down from the top position of the sample changer. Next position: The sample plate turns into the next position.

The calibration of a TR 250 can only be carried out if it is marked as active in the hardware-center in the configuration. Via the menu item „Titrator“ the calibration will be started by clicking on “Calibrate “. In the calibration window the measuring input and the drift can be adjusted. The selection and the parameter are identical with the parameters of a measuring value in a method. There, these parameters are described in detail. The temperature can be entered manually or can even be measured automatically if a Pt 1000 is connected. The values for slope in % and zero point in pH will be shown under „Setting calibration“. Via “Buffer for calibration“ any desired number of buffers can be selected. Always one straight line will be calculated. With a buffer a slope of 98% will be defined and only the zero point will be calculated. With two buffers on straight line through these two buffers will be calculated, with more buffers a straight line according to the method of least error squares.

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One additional buffer can be added via the menu item “Buffer“ “Add“ or can again be deleted with the menu item “Delete“.

If a buffer will be added, a listbox appears from which the desired buffer can be selected.

The calibration will be started with “Buffer“ „calibrate “.

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One further method to start a calibration of a measuring value is to click on the symbol in the current buffer line marked. The recorded mV-values will be shown via “Value“ up to the next calibration.

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6. Database The database can be used from the level “User“. From the navigator (main menu) it will be opened via the push button “Database center“.

On the left side the selection of the samples takes place. Data fields shown in the upper violet field will here be used as special criterion. On the right side of the screen the menus and, in index cards, the properties of the sample selected will be shown.

The menu item “Data“ contains the following possibilities:

Import ASCII: With this function TitriSoft datasets can be imported, which have been exported with the function „Export ASCII“. Subsequently, the datasets have the status „imported“. Export ASCII: With this function individual datasets can be exported in an own TitriSoft data

format. A part of the information can be visualized as text information in a text editor, the titration curve is saved binary in order to avoid any manipulation of the original measuring data. Export Excel: The data points of the titration curve will be exported in an Excel file. The

format is here the same as with a sample list. The numbers will not automatically be detected as numbers, but firstly with the usage or with manual allocations. Print: The marked samples or the marked sample will be printed. If a sample is printed the

printout will be carried out as individual sample on an DIN A 4 sheet, if more samples are marked, the printout as carried out automatically as curve list. Delete datasets: The samples marked will be deleted. Delete all: All samples will be deleted.

The menu item “Curve“ contains the functions:

Measuring points yes/no: In the titration curve the individual measuring values will be represented or faded out. Show derivation: The first derivation of the titration curve will be shown. Additional calculations: Analysis for photometric titrations or LF-titrations (description see

formula editor) Number EQs: It is possible to show up to five equivalence points in the titration curve. The

calculation will be carried out on the basis of a smoothed titration curve. The degree of smoothing depends here on the number of the measuring points. The results can thereby

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differ from the EQs automatically calculated. If with the EQs calculated in the formula it is worked with a normal or strong smoothing, the EQs are identical.

It is possible to add a calculation to a sample. This sample will be described in detail later on. Only added calculations can subsequently be changed or deleted.

Of a marked sample the data points, the method and the results with the titration curve can be put out as pdf-file. The pdf-files will automatically be saved in the \PDF-directory under the sample name.

Samples can be checked and released. The check can only be carried out by someone that has the authorization “Expert“. The testing person must not be identical to the one who has carried out the titration. For the release at least one “Laboratory director“ is necessary, who must not be identical to the persons who have carried out or released the titration.

The characteristics of a sample will be shown in the register cards:

Curve: The titration curve will be represented. Sample information: The results of the titration will be listed, additionally possible subsequent

calculations. Data points: The individual data points of the titration will be represented. Method: The Overview on a method will be shown. Method procedure: The method with its current parameters will be shown. If a method is to

be saved with the parameters of the sample, the method must be released. Changes can only be carried out in a copy.

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6.1 Configuration File 5.3.3. Direct Operation with Titrator and Sample Changer

6.1 Configuration File TitriSoft saves the directory, in which the database is saved in, in an ini-file („titrisoft.ini“). The file “titrisoft.ini“ can be viewed and changed with a text editor. The “Editor“ contained in Windows is well appropriately suitable for that. It will be started via the Windows-Start “Button“.

There, it can be started via the menu “Accessory“ “Editor“. It is also possible to automatically start the ini-file in the Windows-Explorer via double click.

In this ini-file the information [Database] is located and directly in the next line the path specification, where the current database is saved, directly behind “File =“.

This path specification can be marked with the mouse, as shown in the figure below, and can subsequently again be deleted.

If the line is deleted then, except for “File=“, the ini-file will be saved.

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6.2. Selection of a Sample 5.3.3. Direct Operation with Titrator and Sample Changer

For this, “Save“ will be pressed in the editor via the menu item “File“. If the saving procedure does not work, the ini-file might be write-protected.

With the following start of TitriSoft all database available will be shown in the TitriSoft-directory. Then, the current database can be selected.

6.2. Selection of a Sample The samples will be listed on the left side of the screen. The sorting will be carried out according to the criteria defined in the head.

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6.2. Selection of a Sample 6.2.1. Sort and Select Samples

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In the example in the following figure it is sorted according to the method name and within the method name according to date.

6.2.1. Sort and Select Samples In order to sort samples according to particular criteria, the criterion will be marked with the mouse and, with pressed mouse button, will be moved upwards into the violet area.

A second criteria can be moved upwards in the same way. If it will be placed directly below the first property, the samples will be sorted according to the first criterion and within this sorting according to the second criterion.

6.2. Selection of a Sample 6.2.2. Adjust Selection Criteria

Within this overview-sorting it is still possible to sort according to the remaining criteria.

In this example it has been sorted according to method, here the method „Chloride“. Within the method it is sorted according to date. Then, there still remains the internal TitriSoft ID-number of the sample, the name of the sample and the name of the person who has carried out the titration.

If now the field “Measurement ID“ will be clicked on with the mouse, the sorting will be carried out according to ID-numbers in ascending order. If now the field is again clicked on with the mouse, the sorting will be reversed and will then be descending. In this way it is possible to sort in all data fields and to reverse the sorting.

6.2.2. Adjust Selection Criteria The selection criteria can be determined even further. Thus, the function “Adjustment“ will be marked with the mouse.

6.2.3. Detail Selection Criteria

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6.2. Selection of a Sample 6.2.3. Detail Selection Criteria

Then it is possible to determine the selection characteristics explicitly.

If e.g. only results of a method “Chloride“ are to be shown, the method will at first be selected from the selectable information, as link “Equals“ and as method “Chloride“. The method can now be picked from a list.

This query can be saved under a name, can again be loaded and used. The selection will be realized with “OK“ or „ Use “.

After the selection, now only the results of a method Chloride will be shown.

Via the menu “Filter“ the selection can be undone with “Clear All“, then all results will again be shown.

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6.3. Export and Import 6.3.1. Text Information

This determination can only be recommended for the experienced user and will not further be supported by Schott Instruments. This function must only be used after a data backup and after manifold tests.

6.3. Export and Import The titrations can be exported in two different ways:

Export as TitriSoft-specific ASCII-file with binary information and as Excel-format only for the measuring data of the titration curve.

6.3.1. Text Information The sample will be marked and can then be exported via the menu “Data” and “Export Excel“.

A dialogue appears for the input of the file name. The file-ending “*.smpl“ is automatically determined and can not be changed.

In this example the file “Chloride example.smpl“ has been generated.

The file can be opened with a editor and the information in this file can be corrected and added. However, a number of information is protected against changes in the binary format.

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6.3. Export and Import 6.3.2. Pdf-Files

Such a file can again be imported via the menu item “Data“ and “Import ASCII“.

The file can be selected and via “Open“ the import will be carried out. The export and import work only with one sample.

A method which was imported in this way has the status “Imported“.

6.3.2. Pdf-Files

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6.3. Export and Import 6.3.3. EXCEL

It is possible to create pdf-files of a sample from: The data points as list The method as also in the method printout The results of the sample as also with the individual documentation in the titrations-center.

The pdf-files will automatically be created with sample name and date as components. The pdf-files will be stored in the TitriSoft-directory “\PDF“ in the subdirectory “\Samples“.

Due to the file names of the pdf-file a secure allocation is possible. The method “Chloride“ is located with name and date of the pdf-file creation in the directory “\Methods“.

Files that are saved in the data base are stored in the directory “\Samples“

6.3.3. EXCEL The Excel-export will be carried out via “Data“ and “Export Excel“.

It is possible to enter directory and file name, the ending “*.xls“ will be added automatically.

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6.4. Information on a Sample 6.4.1. Graphic

The file will be stored without the necessity that Excel has been opened and even without having Excel installed.

The file can be opened by double clicking with the mouse. This is only possible if Excel is installed on the computer. Then, the chart of the measuring data of the titration will be shown. If the values have not been converted as numbers, with a simple multiplication by 1,00 numbers can easily be converted from this.

6.4. Information on a Sample The following information belong to a sample:

Titration curve a graphic Results Data points Method

6.4.1. Graphic Usually, the graphic will be represented on the x-axis including the consumption values and on the y-axis with the measuring values. Special titration such as pH-Stat can also have other representations. The data slots will be represented above in the graphic. If e.g. the first derivative will be selected, the point “Der” for “Derivative” appears additionally above in the graphic. A represented equivalence point bases on a smoothed titration curve and is identical to an EQ in a formula, which has been determined with normal or strong smoothing. The degree of smoothing depends on the number of data points. The curve can be zoomed by clicking on a point with the mouse and then moving the desired window to the right with pressed mouse button. If the mouse will be moved to the left with the left mouse button pressed, the original graphic will again be loaded.

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6.4. Information on a Sample 6.4.2. Sample Information and Results

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6.4.2. Sample Information and Results The sample information contains the results as most important information. The sample information contain:

Characteristics of the measurement, method, user etc. Results of the sample Electronical signature

The characteristics are:

Method name Date and time of the titration The status: Ready, aborted, imported The sample designation The sample number, normally the weighted sample The position in the sample list The name of the user, who has carried out the titration.

The method results will be listed in two columns, on the left side the name and on the right side the numerical value. The electronical signature consists of a (technical) check of somebody who is authorized but has not carried out the check. The electronical release must be carried out by a third person, who also needs a special authorization. The electronical signature is carried out by specifying date, time, and function.

6.4. Information on a Sample 6.4.3. Data List

6.4.3. Data List The data list contains the data points in a chart. Normally, the chart contains the ml-values of the reagent, the measuring values in mV or pH or even another unit and the time in seconds. A data field “Buffer” will be necessary for special applications (ISE measurement and Gran-Addition). A derivative “Der” will be shown as soon as the graphic has been activated.

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6.4. Information on a Sample 6.4.4. Method

6.4.4. Method The method will be represented in the same form as known from the method center. The method parameters only comply to the parameters with which the current titration has been carried out if they have been released and, thus, can not be changed anymore. Changes of a method in the data base will not be saved in the data base and will be lost as soon as TitriSoft will be shut down.

6.4.5. Subsequent Calculation A subsequent calculation is always possible. Basically, it is possible to visualize the first derivative in the first graphic and up to five equivalence points in the graphics. Due to the location of the equivalence points it can then be decided whether a smoothing for the subsequent calculation is appropriate or an analysis window. Equivalence points visualized in the graphic comply with equivalence points calculated in a formula with a normal or strong smoothing, depending on the number of data points. The less data points, the less stronger the smoothing must be. In the graphic conductometric or photometric equivalence points can likewise be calculated.

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6.4. Information on a Sample 6.4.5. Subsequent Calculation

A calculation formula will be added by the menu item “Calculation” “Add”. In the first step a new line “New result” appears in the register card “Sample information“. This can be edited with “Edit”. For the subsequent calculation nearly all variables are available, but not Titer since you could well have changed your value in the mean time and the end measuring values. The values for the calibration will cause an error message since they are possibly not valid any more.

The creation of a formula has been described in chapter 4. The following example shows that a calculation with a smoothing can result in a (slightly) different value for the equivalence point.

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6.4. Information on a Sample 6.4.6. Add a Calculation

6.4.6. Add a Calculation A calculation formula will be added with the menu item “Calculation” “Add“. In the first step a new line “New result” appears in the register card “Sample information“. This can be edited with “Edit“.

The creation of a formula is identical to the creation of a method. However, with the subsequent calculation it is only possible to enter names for results. They will not be added to the variables in the method-center! Thus, no example and no titer can be subsequently calculated. In such a case a result must be calculated and the value must subsequently be entered manually.

6.4.7. Change of a Calculation A formula will be edited with the menu item “Calculation” and “Change“.

Thus, am equivalence point can again be recalculated with e.g. a smoothing. With the menu item “Delete” a subsequently added formula can again be deleted.

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6.4. Information on a Sample 6.4.8. Delete Samples, Reorganize Database

Original calculations can not be edited and deleted. Added formulas will be also be traced in the Audit Trail.

6.4.8. Delete Samples, Reorganize Database Samples can be deleted in the data base. Nevertheless, some rules must be considered:

Only users with the level Administrator can delete data. Automatically, a copy of the entire database will be generated. There will be an entry in the Audit Trail, which will be provided with a comment.

After the deletion there are numerous empty fields in the database, which will thereby not change its size on the hard disk. Thus, all file accesses will still take the same time as prior to the deletion of the data. Then, in the configurations-center under the menu item “Data base” and “Repair and compress” the data base can be compressed. Thus, all empty fields will really be deleted. From version 2.51 the TitriSoft database will be protected via a password. If an older database will in this way be compressed, this password will automatically be added.

6.4.9. Delete Samples Samples will firstly be marked. It is also possible to mark the title in order to mark all samples listed above. But the securest way to generate a query is still to take back all sorting elements (mark respective fields with mouse, keep pressed left mouse button and move back to the title). The samples can then be sorted according to e.g. date or even other characteristics by clicking on the title with the mouse (left button). Then the upper sample will be marked and subsequently the last sample with mouse button pressed. All samples will be marked and can then be deleted.

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6.4. Information on a Sample 6.4.10. Downsize Database

6.4.10. Downsize Database The database can be minimized in the following ways:

Compression in the configurations-center Deletion of results (or also methods and work lists) and subsequently compression Send database to Schott Instruments and have it minimized there.

The shipment to Schott Instruments is the only way to remove a password from the database.

6.4.11. Data Backup A data backup of the entire data including methods, results and work lists will be carried out in the configurations-center via the menu item “Database“ and „Backup database “.

A copy of the entire database will be created in the database directory. Date and time will be added to the name of the database. An automatic saving will automatically be carried out in the same way when measuring values will be deleted.

6.4.12. Edit Database An existing database can be edited by adding configurations, methods, results and work lists. All information can be deleted, however, it is necessary that two user with administrator rights confirm this deletion process. Additionally, an entry into the Audit Trail with a comment will be carried out. In case of a deletion, a certain order must be adhered to:

1. Delete samples 2. Delete work lists 3. Delete methods 4. Delete configuration

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6.4. Information on a Sample 6.4.12. Edit Database

However, the succession of 1 and 2 can is interchangeably. With samples it is not possible to edit existing results. However, it is possible to add calculations; these can also be edited and changed.

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7.1. Electronic Records

7. FDA-Requirements The FDA (Food and Drug Administration) demands a lot from the software, which will be used in its field of activity for the storage of electronical information. The requirements are specified in 21 CFR Part 11. It applies e.g. for pharmaceutical companies.

7.1. Electronic Records Electronic Records are all methods, titration results and variables within TitriSoft that influence the results. Work lists will not considered as Electronic Records since they do not influence the results they will respectively be documented with the results, e.g. do not enter a weighted sample. The FDA defines electronical records as follows:

The FDA requires:

Access control: Not everybody is allowed to use the software, it is necessary to enter name and password; there are a number of requirements, such as validity period of a password. Backup of data: Complete copies must be possible. Audit Trail: It must be possible to save all changes and an Audit in a human-legible form

must be provided for. Electronical signature: A “Signature” of minimum two different persons for e.g. erasing

procedures. The following describes the implementation within TitriSoft:

7.2. Access Control TitriSoft can only be used if one has logged in by means of the user name and the password. With the initial login procedure, one is asked to enter a new (or for the first time at all) password. All old passwords will be saved and must not be used again. With a new input the new password must be repeated.

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7.2. Access Control

Users will be created and administered in the configuration-center. Only an administrator can create and administer users. If a user is to be deleted, thus, two administrators must be involved! The following menus are available:

User: Here it is possible to define and delete user. Print: Here it is possible to print user data (as summary) – passwords will not be visible). Pdf: Pdf-files that look like the printout will be created automatically or manually.

The menus will be available if “users” will be clicked on on the left side of the screen and the registration card “User” will be activated.

With “Print” it is possible to generate a printout of all users.

The printout contains the following information:

Access level Login name Complete name Active yes/no Function

The pdf-file will be generated in the same way via the menu “Pdf” in the pdf-subdirectory of TitriSoft.

The form complies with the printout.

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7.2. Access Control

New users will be generated under “Users” and “New”. There, they can also be deleted. If a user has forgotten his or her password, this password can be deleted via „Delete password“. Independent of the fact if a password will be allocated the user must change his or her password with the initial login-procedure.

The characteristics of a user are:

User type or level (Login-)name Complete name Active yes/no FunctionPassword

There are five levels for users. These levels adhere to certain functionalities:

Level Functions Routine user Can titrate in the titration center User Has additionally access to the data base Expert Can additionally use all functions in the analyses-center (except for release),

such as create and change methods, created variables. Can generate configurations, can adjust and view log-files. Can view the Audit Trail. Can check samples and methods.

Laboratory director Can additionally release samples and methods. Administrator Can additionally create and delete users The user name is an essential security element for accessing the TitriSoft functions. Thus, it should not be known generally. Basically, such an access concept is only reasonably i fit is worked with an operating system that principally uses an access authorization, such as with Windows XP Professional or Windows 2000. The complete name should bet he real name, it will be used with the documentation. A user can be active or inactive. Inactive user can not work with TitriSoft, but should not be removed from the data base for the sake of subsequent documentations.

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7.2. Access Control

The function of a user can freely be entered, in order to guarantee that all possible or even uncommon functions can be used.

Normally, the administrator will assign passwords, in order to assure that unauthorized persons have no access to the software. The password should then be changed with the first access procedure.

After the input the new users will be added to the list.

There are some requirements concerning the password:

Time period for the password validity in days Minimum number of signs for the password Decision, whether a password must be included Decision, whether a special sign must be included in the password

Additionally, here it will be adjusted in which timer intervals (in days) the database is to be saved.

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7.3. Copies of Electronic Records

7.3. Copies of Electronic Records Basically, electronical copies can be generated in two different ways:

Copy of the entire data base. This form needs TitriSoft or (restricted because of saved binary data) Access in order to have again access to these data. In the form of pdf-files independent of TitriSoft and Access.

The data base will simply be saved by clicking onto “Database“. Then a complete copy will be created in which the current date and the time will be added with the file-name. The file-names of copies from the copies could need some time to getting used to them.

For all additional information following it is possible to create pdf-files that will be copied into the pre-set directory with the automatic file-name. Pdf-files can be generated for:

List of users

Documentation of methods

Sample information data points Results and curves Method in the data base center

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7.4. „Audit Trail“

Sample list vertical in the screen form in the titration-center Defined report in the titration-center

7.4. „Audit Trail“ The Audit Trail consists of a data base chart in which all changes of electronic “Records” will be saved. The Audit Trail can be viewed and documented in the configuration center. On the left side of the screen the “Audit Trail” will be clicked on with the mouse. On the right side the chart will be shown.

The Audit Trail information can be saved or documented in the following way:

Save copy of the data base with data base. Print content or better marked content. Print content or better marked content as pdf-file. The pdf-file is identical with the printout in

respect of the content. The output of the pdf-file will automatically be carried out into the pdf-directory.

At first, choose desired data for the printout. A printout of an Audit Trail over a longer period of time can well contain several hundred pages. With the selection one should be aware of this fact. Entries will be marked by clicking with the mouse on the first entry and then the last entry will be marked with pressed shift-key and left mouse button.

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With the menu “Print“ and ”Print Audit Trail“ the print preview will be shown from which the printout can be started.

With the menu “Pdf” and „Audit Trail as pdf“ the pdf-file will automatically be generated without any further queries.

The file will be saved in the titrisoft-directory „\PDF\Audit Trail“.

The Audit Trail can be sorted according to all criteria available. The selection criterion will be marked with the left mouse button and then moved to the upper violet part with the mouse button pressed („Drag and drop“). Here, it is possible to combine multiple criteria as shown in the following figure. Here, the charts available will be shown.

The database activities normally refer to addition, changes and deletions. With users e.g. unsuccessful login will additionally be saved. Unsuccessful logins will cause an automatic ban of the user. The following figure shows the database activities possible.

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In the following figure it will additionally selected who has carried out the changes.

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7.5. Electronical Signature

If the small plus-sign in front of the user will be clicked on with the mouse, the respective entries will, in some cases with additional comments, be shown.

The printout (and the pdf-file) complies with the screen information.

The selection criteria will also be printed in order to prevent that it is assumed that it concerns a complete selection of the data base.

7.5. Electronical Signature The relevant electronical information in TitriSoft is the methods and the titration results. Both can be provided with an electronical signature. An electrical signature consists always of two independent elements:

“Technical check“ by someone with respective authorization “Release” after technical check has been carried out by a further person with respective

authorization. Here, the method creator, the tester and the releasing person must be different persons.

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Thereby, it is also possible to check or release various methods in a row. After the login any number of methods can be checked or released. After a “Logoff” (above left in the screen) the newly logged-in user can check or release in series according to his authorization.

For the check the method will be selected in the left side and then be checked via “Method“ and “Check Method“.

For every process it is possible to generate a comment which will be entered into the Audit Trail.

The method information will respectively be updated. Date and time as well as the complete name of the tester and his or her function will be entered.

The release will be carried out analogue to the checking procedure.

If in TitriSoft a user is still active, i.e. he or she ahs not yet logged-out, a login-window appears, in which the releasing person can enter name and password.

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Accordingly, the input of a comment is also possible.

In the method both processes, check and release, will be documented and at the same time also printed out.

A pdf-file of the method printout will automatically be generated for a released method.

In the “Printout” date and time of the check and release procedure are documented. Methods that are not checked and released have as pre-setting 30.12.1899 or 01.01.1980 entered in the method.

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For samples the procedure is identical. Via the menu point “Electronical Signature“ and “Check Sample“ a method can obtain its test tag.

With many checks or releases it is recommended to logout in order facilitate the check and release procedures in series.

If a user is still logged in, for every sample a new login is necessary.

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Every check or release can be provided with a comment, which can be viewed in the Audit Trail.

Here, the documentation will be carried out with the complete name, function and date/time.

Accordingly, the release of a sample will be carried out.

Since only three different persons will enable a release (creator, tester and releasing person), an error message will appear as soon as a person wants to assume two different tasks.

A comment is also possible after a sample has been released.

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The check and release procedure will be saved with the sample.

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SCHOTT Instruments GmbH Postfach 24 43 Tel.: +49 (0)6131/66-5111 D-55014 Mainz Fax: +49 (0)6131/66-5001 Hattenbergstraße 10 E-Mail: [email protected] D-55122 Mainz www.schottinstruments.com

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Manual TitriSoft 2.6 / P