ΒΙΟΑΝΟΡΓΑΝΑ ΚΑΤΑΛΥΤΙΚΑ ΚΕΝΤΡΑ ΚΑΙ … · karaindrou Κ. 18. karapati s. 19. kaparou m. 20. kazantzaki Μ. 21. koumoulis d. 22. kyropoulou d. 23. maniati

FOREWORD

The Institute of Materials Science (IMS) is one of the eight Institutes of NCSR "Demokritos”. It wascreated from the pre-existing Department of Physics and is one the largest Research Institutions inthe country, employing a permanent staff of 26 researchers, 6 scientific officers, 3 technicians and 2administrators.

In addition, through research projects the Institute employs 25 postdoctoral fellows, 43 graduatestudents, as well as hosting students and visiting researchers from around the world.

The main objectives of the IMS are: a ) to conduct basic and applied research in selected areas ofmaterials science, b ) the development and application of modern physical methods in the study ofancient materials and finds, and c) to offer specialized high quality services to Greek society andindustry.

The IMS sets a priority on the development of expertise in priority areas of national and Europeanresearch such as the environment, health and sustainable development. Particular emphasis is givento the development of interdisciplinary research activities through the implementation of a largenumber of joint research programs with laboratories, universities and research centers in Greece andabroad. Other key activities include collaborations with industrial partners to exploit scientificadvances, and the provision of high quality graduate training and education.

This report presents a review of scientific achievements, departmental activities and financial datafor 2011. In this year the institute implemented more than 62 research projects financed orsupported by European Union programs, the General Secretariat for Research and Technology,government organizations and enterprises. From these activities, the income generated in 2011exceeded 3.25 million € of which 3 million € came from competitive and other research programsand 250.000 Euro from the provision of scientific and technological services.

Dr. G. PapavassiliouDirector, Institute of Materials Science

INSTITUTE OF MATERIALS SCIENCE 2

CHART OF THE INSTITUTE OF MATERIALS SCIENCE(2011)

*coordinator

VICE DIRECTOR

Dr. K. TROHIDOU

SCIENTIFIC ADVISORY BOARD SECRETARY

IIELECTRONIC AND

COMPOSITEMATERIALS

Dr. A. Travlos*

IIIARCHAEOMETRY

Dr. Y. Maniatis*

DIRECTOR

Dr. G. PAPAVASSILIOU

IMAGNETIC AND

SUPERCONDUCTINGMATERIALS

Dr. G. Papavassiliou*

(Provision of Services)TECHNOLOGICAL AND

INDUSTRIALAPPLICATIONS


CONTENTS

FOREWORDCHART OF THE INSTITUTE

1. GENERAL INFORMATION

INTRODUCTION 5PERSONNEL 8

2. STATUS QUO

Income - Expenses 13Program Funding 14Publications – Conferences – PhD theses 15

3. INFRASTRUCTURE

Equipment 16Services 18

4. RESEARCH PROGRAMS

PROGRAM I: MAGNETIC AND SUPERCONDUCTING MATERIALS 19Magnetic Nanomaterials 21Crystallography Laboratory 28Nuclear Magnetic Resonance Spectroscopy 33Heavy Fermion Systems 38Computational Materials Science 43Theoretical Physics of Multielectron and magnetic systems 48Nanofunctional and Nanocomposite Materials 54Bioinorganic Catalyst Centers and Mixed valence Valence Multinuclear Complexes 61

PROGRAM II: ELECTRONIC MATERIALS 67Electronic and Composite Materials 69Molecular Beam Epitaxy and Surface Science 75Sol-Gel / Pulsed EPR Laboratory 80


Advanced Ceramics Laboratory 86

PROGRAM III : ARCHAEOMETRY 94Radiocarbon dating and provenance of biological and lithic materials 96Luminescence dating and solid state dosimetry 101Paleoenvironment and ancient metals 105Ceramics and composite materials 112Stable isotope unit 121Laboratory of Archaeometry 127

PUBLICATION LIST 129


GENERAL INFORMATION

INTRODUCTION

The mission of the IMS is to support high-quality interdisciplinary research and thepromotion of innovation in materials science and technology. The principal research aim isthe synthesis, preparation and study of the structure and physical properties of novelmagnetic, superconducting and semiconducting materials with emphasis on nanostructuredmaterials. In addition, there is a major complementary research activity in the field ofArchaeometry on the study of archaeological materials and the understanding of ancienttechnologies and their evolution.

The objectives of IMS implemented through the three main research programs cover:

Synthesis, characterization and theoretical study of the physical properties of new materialsfor product development and high-tech devices. Development of analytical techniques andmethods for the control of materials in order to provide specialized technical services andtechnology transfer to industry. Training of young scientists and technicians through post-graduate study programs and their participation in the research activities of the Institute.

The IMS has a large number of laboratory facilities unique in Greece, which enable aninterdisciplinary approach to research activities. New techniques are developed for thesynthesis of nanostructured materials (nanoparticles, thin films and nano-wires) forapplications based on their unique physical properties in a range of fields such as magneticrecording media, magnetic quantum dots, biological applications (dialysis, magnetichyperthermia), sensors in low temperature semiconductor devices, catalysis, etc. Thussystematic investigations of the physical properties of these materials are carried out for thepurpose of understanding the underlying physical mechanisms to improve theireffectiveness and efficiency. Experimental techniques and computational physics methodsare used in conjunction for the refinement of theoretical models. Central to these activitiesare the Magnetic Thin Films and Nanostructured Materials laboratories (including theMolecular Beam Epitaxy (MBE), Magnetron Sputtering, and Laser Ablation facilities) , SolidState Chemistry laboratories, Synthetic Chemistry and Liquid Chemistry nanostructuredmaterials laboratories, as well as the large number of characterization techniques such ascontinuous and pulsed Electron Paramagnetic Resonance (EPR), Nuclear MagneticResonance (NMR) covering the temperature range 2-1000 K, Mössbauer spectroscopy inmagnetic fields up to 7 Tesla, SQUID magnetometery, VSM and Hall sensor magnetometry(the sensitivity of the latter reaches 10-9 emu), powder and monocrystal X -raycrystallography, and the high precision Electron Microscopy SEM and TEM etc. The institutealso houses the unique facilities of the Laboratory of Archaeometry which, in combinationwith the IMS infrastructure, contributes significantly to the understanding and promotion ofthe country’s cultural heritage. Lastly, we must note the significant contribution that the IMSmakes to the needs of the wider society and industry in offering services such as non-destructive structural testing (Mobile Radiography unit), liquid Helium for use in medicalMRI units, as well as electron microscopy services, asbestos detection, and carbon- 14 datingamongst others.

The research activities of the IMS are grouped into three research programs and oneprogram dedicated to the provision of services. The research programs, as shown in theorganization chart, are:

- Magnetic and superconducting materials ( coordinator Dr. G. Papavassiliou).


- Electronic and composite materials (coordinator Dr. A. Travlos).

- Archaeometry (coordinator Dr. I. Maniatis).

The scientific activities of these programs are summarized as follows :

(I ) Magnetic and Superconducting materials

The aim of this program is to conduct basic and applied research on materials of hightechnological interest in the following areas :

• Hard magnetic materials.

• Magnetic recording media.

• Magnetic nanoparticles , nano-wires , quantum dots.

• Nanoparticles for biological applications (hemodialysis, hyperthermia).

• Left-handed magnetic materials.

• High Temperature Superconducting (HTS) materials and colossal magnetoresistance.

• Heavy fermion systems.

• Hybrid nanostructured materials.

• Molecular magnetic materials.

• Biomolecular magnetic systems.

• Computational condensed matter physics.

• Theoretical many-electron and magnetic systems.

(II ) Electronic and Composite Materials

The activities in this program cover the following areas :

• High dielectric and semiconductor materials for nanoelectronic devices

• Metal- semiconductor Si nanoparticles

• Large energy gap semiconductor nanostructures.

• Conductive polymer coatings and ORMOSIL inhibitors deposited on self-healing metals.

• Nano-containers for drug delivery.

• Antibacterial nano-containers.

• Heat-protection systems for space and satellite applications.


• Advanced ceramic composites with improved mechanical properties.

• Inorganic catalytic materials for chemical and environmental applications.

( III ) Archaeometry

The research areas in the field of Archaeometry focus on the following areas:

• High precision radiocarbon dating, luminescence and ESR.

• Technology and origin of ceramic and glassy materials.

• Origin and distribution of stone materials (marble, obsidian, steatite).

• Archaeometallurgy and ancient metals.

• Geo-archeology and the palaeo-environment.

• Nutrition and organic residues.

• Erosion mechanisms, repair and stabilization of artifacts and monuments.

• Development of restorative materials for antiques and monuments.


1. PERSONNEL

RESEARCHERS

1. ALOUPOGIANNIS P.2. BASSIAKOS Y.3. BOUKOS N.4. DEVLIN E.5. DIMOULAS A.6. DOTSIKA E.7. FARDIS M.8. HEIN A.9. ΚORDAS G.10.KYLIKOGLOU V.11.MANIATIS Y.12.MHTRIKAS G.13.MICHAEL Ch.14.MOSXOPOULOU E.15.VEKINIS G.16.NIARCHOS D.17.PAPAVASSILIOU G.18.PETROULEAS V.19.PISSAS M.20.PSYCHARIS V.21.RAPTOPOULOU C.22.SANAKIS Y.23.THANOS S.24.TRAPALIS C.25.TRAVLOS A.26.TROHIDOU K.

RESEARCH OFFICERS

1. FILIPAKI E.2. GIOKAS M.2. IOANNIDIS N.3. KARATASIOS I.4. SPELIOTIS A.5. XANTHOPOULOU G


POST DOCTORAL SCIENTISTS

1. ΑLEXANDRAKIS V.2. ATHANASSAS K.3. BILALIS P.4. CHRONAIOS A.5. DIAMANTOPOULOS G.6. EFTHIMIADOU E.7. GIANNAKOPOULOU Τ.8. HADJIPANAYIS G.9. KALAGRI A.G.10. KARAKOSTA E.11. KARATZAS E.12. KARTSONAKIS I.13. MAVROULIS S.14. MUELLER N. S.15. SIMSERIDES K.16. STAMOPOULOS D.17. TARKHNYAN R.18. TODOROVA N.19. TSOUTSOU D.20. TZITZIOS V.21. TZIVELEKA A.L.22. VAGENAS D.23. VASILAKAKH M.24. VERMISOGLOU E.25. ZAFEIROPOULOU E.

EXTERNAL COLLABORATORS

1. GAMARI – SEALE E.2. GEORGAKILAS V.3. PETRIDIS D.4. MILIA F.5. PANAGIOTOPOULOS I.6. TERZIS A.7. HATZIPANAYIS G. (Dept. of Physics, University of Delaware)8. CHRISTIDES Ch.


PHD STUDENTS

1. ΑGELOPOULOU Α.2. ΑMENTA M.3. AMPATZIOGLOU E.4. ARISTOMENOPOULOU E.5. ATHANASAKOU N.6. ΑTHANASSOPOULOS G.7. BAKAS M.8. BALASKAS A. (contract)9. CHATZIPAVLIDIS A. (contract)10. CHRISTOFI Α.11. CHRYSSINA Μ.12. FARMAKALIDOU L.13. GEORGOPOULOU A.14. GIANNOPOULOS G. (contract)15. GOLIAS Ε.16. KALAMPALIKI TH.17. KARAINDROU Κ.18. KARAPATI S.19. KAPAROU M.20. KAZANTZAKI Μ.21. KOUMOULIS D.22. KYROPOULOU D.23. MANIATI M.24. MANIOS E. (contract)25. MARAVELIS G. (contract)26. MARGARIS G.27. MARGARITIS I.28. MARINOU A.29. MASTROTHEODOROS G.30. MAVROULIS S.31. OIKONOMOU D.32. PAPAGEORGIOU M.33. PANOPOULOS N.34. PAPPAS G. (contract)35. SOFIANOU M.V.36. TAMPAKOPOULOS D.37. TAPEINOS C. (contract)38. TASSI M.39. THEOFILOU Ι.40. TSAKALOS E. (contract)41. TSELIOS CH.42. TSITROULI D.43. TZIMA TH.


44. TZIOTZIOU M.45. VARELAS G.46. ZEIBEKIS Ε.47. ZIANNI Α.48. ZISSI N. (contract)

TECHNICAL AND ADMINISTRATIVE PERSONNEL

1. CHARITOS A.2. KORDA A. (contract)3. KYRIAZI M.4. MANOLA E.5. MARINOS A. (contract)6. MOUNTZOURIS V. (contract)7. MOUTSOS K. (contract)8. VLESSIDIS V.9. TZIFAS M. (contract)10. ZATTA V.


Comparative details

PERSONNEL

2009 2010 2011

Researchers 25 26 26

Research Officers 6 6 6

Post Doctoral Scientists 26 23 25

PHD scientists 50 63 48

Administrative / TechnicalPersonnel

13 9 10

TOTAL 120 127 115

0

10

20

30

40

50

60

70

2009 2010 2011

Researchers Research Officers

Post Doctoral Scientists PhD Students

Administr./Technical Personnel


2. STATUS QUO

Income

€2009 2010 2011

INCOME 3.778.338,63 3.038.040,18 3.038.040,18

Regular Funding 2.036.603,63 1.369.469,18 1.369.469,18

Income from NationalPrograms 229.919,00 105.087,00 168.212,71

Income from EUprograms 1.386.462,00 1.342.671,00 2.990.057,56

Income from othersources 25.017,00 49.702,00 13.050,00Income from services-third party 100.337,00 171.111,00 248.117,04

0,00

0,50

1,00

1,50

2,00

2,50

3,00

2009 2010 2011

RF

RF RF

NPNP NP

EU EU

EU

OS OS OSServicesServices Services


PROGRAM FUNDING

PROGRAM INCOME (€)

2009 2010 2011

MAGNETIC ANDSUPERCONDUCTING MATERIALS

62.108,14 257.817,40 748.950,85

ELECTRONIC AND COMPOSITEMATERIALS

7.500 1.194.285,07 2.021.022.41

ARCHAEOMETRY 38.287,74 45.357,53 421.038,03

SERVICES

14.702,27 171.111,00 248.117.,04

TOTAL 122.598,15 1.688.571,00 3.439.128,33

2009

2010

2011


PUBLICATIONS – CONFERENCES - THESES

2009 2010 2011

PUBLICATIONS ININTERNATIONAL JOURNALS

141 113 93

IN INTERNATIONALCONFERENCES

36 57 80

OTHER 34 17 38

CHAPTERS IN BOOKS 9 10 4

CITATIONS 2773 2785 4545

INVITED TALKS 23 30 36

PhD THESIS 12 8 5

141

11393

36

5780

43

274

31

30

36

12

12

5

0 50 100 150 200 250 300

2009

2010

211

Inter. Journals Intern. Conferences Chapters in Books Invited Talks PhD Thesis


EXISTING EQUIPMENT

INSTRUMENTS

Materials Preparation

Arc melting and induction RF melting *- Melt-spinning vacuum system with RF heating

Solid State Chemistry and Liquid Chemistry (Sol-Gel etc.)

Thin Films and Nanostructured Materials:- Molecular Beam Epitaxy (2 systems) *- Magnetron sputtering (3 systems) *- e-beam evaporation *- Thermal evaporation *- Laser Ablation *- Ion beam sputtering *- UV-lithography down to 5 microns *

Materials Characterisation

Spectroscopy- Mössbauer superconducting magnet with 0-7 Tesla **- EPR continuous wave in regions X and Q- Solid state NMR (in 2.35 , 4.7 and 8 Tesla - the frequency range 1 MHz-800 MHz)

**- Nuclear Quadrupole Resonance (NQR) **- ICP *- FT-IR **- HP-Network analyzers (40MHz-2GHz, 100MHz-13GHz)- Gamma-spectroscopy for neutron activation analysis.

X-ray diffractometry- Single–Crystal and powder diffraction

Magnetometry- SQUID magnetometry, **- Vibrating Sample Magnetometry (VSM), *- Ac- susceptibility ( superconducting magnet with 0-12 Tesla) **- Kerr Microscopy *- SQUID gradiometry *


Microscopy :- Electronic, Optical and Atomic Force Microscopy- Scanning Electron Microscopy (SEM) **- Electronic microscopy (TEM) **- Atomic Force Microscopy (AFM) *-- Magnetic Force Microscopy (MFM) * variable field to 0.2 T-- Metallographic / Petrographic and stereoscopic optical microscopy

Thermogravimetric analysis (TGA) *

Dielectric measurement device up to 40 GHz.

Mechanical Properties Measuring System Dating Measurements- Radiocarbon dating (14C) with measurement arrays for gaseous sample- Thermoluminescence System **- Optical Luminescence- Portable -gamma scintillation spectrometer

Other Systems

60Co gamma- ray and X-ray Radiography **

Active plasma processing equipment

Helium Liquefier **

Two reactors for plasma restoration of metal surfaces

* Used by many groups within IMS.** Used by groups outside IMS.


SERVICES

The scientific infrastructure and research experience of the IMS allow it to offerunique services in Greece. The IMS has placed particular emphasis ontechnological and industrial applications useful for industry and beneficial tosociety.

Brief description of services.Industrial Gamma-ray and X-ray Radiography.Dating with 14C and Luminescence techniques.

Identification and Analysis of asbestos. ICP for elemental analysis. X-Ray Diffraction. Magnetometery.

Electron Microscopy (SEM, TEM).Spectroscopy (Mössbauer, EPR, FT-EPR, NMR, NQR).Mechanical Properties of Materials.Metallography and Ceramography.Gas Chromatography (FID and TCD).Liquefaction of Helium.Advanced films and coatings.Atomic and Magnetic Force Microscopy (AFM).


MAGNETIC NANOMATERIALS

CRYSTALLOGRAPHY

NUCLEAR MAGNETIC RESONANCE (NMR) SPECTROSCOPY

HEAVY FERMIONS SYSTEMS

COMPUTATIONAL MATERIALS SCIENCE

THEORETICAL PHYSICS OF MULTIELECTRON AND MAGNETICSYSTEMS

NANOFUNCTIONAL AND NANOCOMPOSITE MATERIALS

BIOINORGANIC CATALYST CENTERS AND MIXED VALENCEMULTINUCLEAR COMPLEXES SUPERCONDUCTIVITY ANDMAGNETIC OXIDES

RESEARCHERS

E. Devlin, M. Fardis, E. Moshopoulou, D. Niarchos, G. Papavasiliou, V. Petrouleas, M.Pissas, V. Psycharis, C. Raptopoulou, Y. Sanakis, S. Thanos, C. Trapalis, K. Trohidou

PERMANENT SCIENTIFIC STAFF

M. Gjoka, T. Speliotis

PROJECTS

PROGRAM IMAGNETIC AND SUPERCONDUCTINGMATERIALS

PERSONNEL



G. Diamantopoulos, K. Simserides, V. Alexandrakis, V. Georgakilas, T.Giannakopoulou, M. Giannouri, A. Ioannidou, E. Karakosta, M. Vasilikaki, E.Vermisoglou, D. Stamopoulos, A.K. Theofilou, A. Terzis, N. Todorova, V. Tzitzios, E.Zafeiropoulou

PhD STUDENTS

G. Giannopoulos, E. Manios, T. Tzima, M. Chryssina, D. Koumoulis, N. Panopoulos, D.Tsitrouli, I. Theophilou, M. Tassi, A. Christofi, M.V. Sofianou, S. Karapati, T.Kalampaliki, G. Margaris, A.N. Georgopoulou, G. Varelas


MAGNETIC NANOMATERIALS

Research Director: Dr. Dimitris NiarchosPermanent Research Staff: Dr Eamonn Devlin, Dr. Thanassis SpeliotisContract Researchers: Dr. Vasilis AlexandrakisPost-Doctoral Researchers: A. IoannidouVisiting Researchers: Dr. George HadjipanayisPhD Candidates: Mr. George Giannopoulos, E. Manios

External Collaborators:George Hadjipanyis, U of Delaware, USAJosef Fidler, TUW, Austria,Manfred Albrect, U of Chemnitz, DEC. Soukoulis, U of Iowa, USAD. Fiorani, ICN, Rome, ItalyE. Torbjorn, Obducat, SdedenM. Mamoun, KTH, SwedenA. Jacquot, Fraunhofer, IPM, GermanyM. Martin, CSIC, Madrid, SpainG. Noriega, CIDETE, SpainH. Philip, SIEMENS, GermanyO. Gutfleisch, U of Darmstadt, GermanyG.C. Papaefthymiou, U. of Villanova, Baltimore, USA.S. Cadogan, University of Manitoba, Winnipeg, Canada

Sputtering systems in our laboratoryUHV deposition system:

Deposition chamber with six con-focal guns Load lock preparation chamber 4 inches substrate heating station (800 0C), ±2% uniformity, RF bias/etching. In-situ calibration of deposition rate 2 DC and 2 RF power supplies.

Two more HV deposition systems, with up to three guns, DC/RF power supplies.

Activities:1. FePt graded media for perpendicular magnetic recording

Today, as the conventional magnetic recording technology is finally facing itsfundamental limit due to thermal instabilities in the longitudinal magnetic media thestrong interest for perpendicular recording is increased. Among the large variety ofmaterials for perpendicular recording, e.g. L10, CoPt and FePt, Co/Pd artificialstructures and SmCo5, FePt explored in our laboratory, due to excellent properties:high magnetocrystalline anisotropy, strong corrosion resistance and his uniquethermal stability for grain diameters less than 3nm.Our approach is:


Growth of FePt single layers, 10nm thick on MgO (200) substrates. Growth of hard/graded FePt structures on MgO substrates. Growth of semi-core like L10, FePt/A1 or Co, shell structures. Transfer this work, on MgO substrates, to amorphous (glass), industrial

substrates.

FePt single layers on MgOFig. 1 and 2 shows perpendicular magnetization curves of the films deposited onMgO(200) substrates at different temperatures. The coercivity of the films drasticallyincreased with increasing Ts from 300 0C to 650 0C.

Fig. 1: XRD patterns of FePt films fabricatedon MgO substrates.

Fig. 2: Perpendicular magnetization curves ofFePt films fabricated on MgO substrates.

Fig. 3: High resolution TEM images on the FePt films grown (a) at 500oC and (b) 200oC. The fast Fouriertransformation (FFT) images of the marked boxes are listed on (c-g). The arrows and description onthe FFT images stand for the orientational directions of the given materials.


Hard/Graded FePt granular layersThe high coercivity field (Hc > 30 kOe) of these materials makes the writing processdifficult using available magnetic write heads. An approach for reducing the writingfield, while retaining the high thermal stability, is through the use of graded ESM, anew class of nano-composite materials proposed for ultrahigh density recordingmedia. Graded ESM with a spatially varying anisotropy Ku(z) offer improvedcharacteristics in comparison to homogeneous, constant K hard/soft bilayer media.At first a single phase L10 FePt layer with high coercive field Hc and perpendicular tothe film plane magnetic anisotropy was deposited on the MgO substrate at 500 0C.The next step was the growth of the graded L10 to A1 FePt layer on top of themagnetically hard L10 FePt layer. Results are shown in Fig. 3,4.

Fig. 4: Cross-sectional image of hard(10 nm)/graded(10 nm)FePt nano - composite

Fig. 5: Variation of the coercive field Hc of hard(10nm)/graded(tx nm) FePtnano - composite with the thickness of the graded layer tx.

L10 FePt on amorphous substratesTexture control and seed layerIn order to obtain the FePt with (001) texture, either the substrate or a suitable under-layer which has a similar atomic configuration to that of the FePt (001) plane andsmall lattice misfit required. Substrates such as MgO(001), SrTiO3(100), Cr(200),Ag(200) are normally used to induce the FePt (001) texture. The correspondingepitaxial relationship is FePt(001)<001>||MgO(100)<001> for MgO, with lattice misfit8.5% and FePt(01)<001>||Cr(100)<110> for Cr, with lattice misfit 5.8%. Thedevelopment of Cr(200) texture is a key to obtain FePt(001) textured films. Anintermediate layer of MgO to prevent the Cr diffusion on FePt is required.


Fig. 6: Cross section TEM ofGlass/Cr(200)/MgO(100)/FePt(100)

Fig. 7: HR Cross section TEM ofGlass/Cr(200)/MgO(100)/FePt(100)

Achievements:

Optimization of L10 ordered FePt single layers Tailoring the coercive field with hard/graded nano-composite media Develop L10/A1 FePt, semi-core – shell nanocomposites and tailor the

coercivity, structural and magnetic properties Exploitation of L10 ordered FePt growth on amorphous industrial substrates,

with perpendicular anisotropy, coercivity in excess of 1T at low (325 0C)deposition temperatures.

2. Thermoelectric materials

There is now an increasing interest in research of improved materials forthermoelectric applications. The properties of thermoelectric materials are

characterized by the Figure of Merit ZT= where S is Seebeck coefficient ρ is the

electrical conductivity, κ the thermal conductivity and T is the absolute temperature.Therefore in order to have a good material it must have a low thermal conductivityand a high power factor. Here we report the synthesis of skutterudite Co4-xFexSb12

powders where Fe substituted Co.

Method: Microwave oven Panasonic 1700 WThe samples were made of Co, Fe and Sb pure metalsafter milling for 30min in order to have homogeneity.Then pellets of 4mm height were produced andsealed in vacuum in a quartz tube. The tube wasinserted in a high temperature brick and covered byCuO which is used for a susceptor as seen in Figure 8.A novel technique for Fast sample preparation in minu-

procedure of tes instead of hours!

Fig. 8: Experimental material synthesisin microwave oven.


In CoSb3 alloys the formation of small, homogeneous particles, has been reportedand was confirmed in our undoped CoSb3 sample Fig. 20a. Figs. 20b and 20c showsthe SEM images for the two iron containing samples which reveal that increasing Feleads to the formation of larger particles, in good agreement with earlier studies onconventionally prepared samples. It is also appeared that Fe could not penetrate intothe lattice indicating the existence of iron phase for the compound with nominalcomposition Co3.2Fe0.8Sb12. SEM results showed that more time in required inmicrowaves so that Fe gets into the skutterudite phase.

Fig. 20: SEM photo of the alloys: a) CoSb3, b) Co3.6Fe0.4Sb12

Also we developed a theoretical model for scalar nanoporous materials with higherZT.

Active Externally Funded research ProgramsOur group is involved in the following Research Programmes

1. NANOPERMAG ( MC-IIF) May 1st 2010- 31 November 2012Title: “Novel nanostructured Permanent Magnets”Role of Partner: Dr. D. Niarchos, Coordinator

Sb

a

b


Beneficiary Prof. G. HadjipanayisBudget: 205,000 EurosFunding Agency: EC

2. TERAMAGSTOR ( ICT-FP7) May 1st 2008- July 31st 2011Title: “Terabit Magnetic Recording Media”Role of Partner: Dr. D. Niarchos, CoordinatorBudget: 935,000 EurosFunding Agency: ECWeb: www.teramagstor.eu

3. NEXTEC( NMP-FP7) May 1st 2008- July 31st 2011"Next Generation Nano-engineered Thermoelectric Converters – fromconcept to industrial validation".Role of Partner: Dr. D. Niarchos, CoordinatorBudget: 325,000 EurosFunding Agency: ECWeb: www.eu-nextec.eu

We have been also grantedREFREEPERMAG (NMP-FP7) May 1st 2012-Arpil 30th 2015Title: “Rare-Erath-Free Permanet Magnets”Role of Partner: Dr. D. Niarchos, CoordinatorBudget: 903,747 EurosFunding Agency: ECWeb: www.rarefreepermag-Fp7.eu

MAGNACORE (Aristeia)- GSRT-ESPA, GreeceTitle: « NOVEL NANOSTRUCTURED MAGNETIC CORE MATERIALS FOR DC-DCconverters »Role of Partner: Dr. D. Niarchos, CoordinatorBudget: 200,000 EurosFunding Agency: GSRT, ESPA, GreeceWeb: www.rarefreepermag-Fp7.eu

Conference Organisation

EUROSENSORS 2011, Athens, Septemember 4-7, Co-Chair Programme Committee

Conference Participation

1. R. H. Tarkhanyan and D.G. NiarchosInternational Conference for Materials and Applications for Sensors andTransducers, ICMAST-2011. Kos, Greece, May 13-17, 2011

2. D. Niarchos, European Conference on Thermoelectrics, Thessaloniki, 28-30 Sept2012

3. D. Niarchos, IC4N, Iraklio, Greece


4. D. Niarchos, EUROSENSORS 2011, 4-7 Sept 20125. D. Niarchos, TNT2011, Tenerife, Spain, 2012, Nov 21-25

Invited Talks

D. Niarchos, The trilemma towards 1 Tbit/in2, IC4N, Iraklio, June 2011D. Niarchos, Graded exchange spring media based on FePt, November 2011,TNTD. Niarchos, Towards 1 Tbit/in2 magnetic recording, June 2012D. Niarchos, Magnetic MEMS, EUROSENSORS 2011, 4-7 September , Athens GreeceD. Niarchos, Towards 1 Tbit/in2 magnetic recording, June 2012

Teaching and Training Activities

Member of PhD Committee

1. E. Zeimbekis, NTUA Greece2. E. Serletis, AUTH Greece

Doctoral Dissertations completed in 2011Name: Efthimios ManiosDissertation Title : Synthesis and characterization of magnetic recording mediaResearch Supervisor: Dimitris NiarchosUniversity where the Thesis was presented: SEMFE, NTUA

Research Consultation EC, Foresight Meeting


LABORATORY OF CRYSTALLOGRAPHY

Research Director: Dr. Vassilis PsycharisPermanent Research Staff: Dr. Catherine P. RaptopoulouPost-Doctoral Researchers: Dr. Athanassios K. BoudalisVisiting Researchers: Dr. Aris TerzisPhD Candidates: Mrs. Anastasia N. Georgopoulou, Mr Georgios VarelasExternal Collaborators: S.P. Perlepes, E. Manessi-Zoupa, N. Klouras, D.P.Kessissoglou, C. Dendrinou-Samara, G. Psomas, A. Salifoglou, P. Kyritsis, J.C.Plakatouras, I. Pirmettis, M. Papadopoulos, G.E. Kostakis, J.B. Baruah, B. Abarca,G. Christou.

Areas of Research:The research activities of the Laboratory of Crystallography cover two main fields:

1. X-ray crystallographic studies from powder samples or thin films and singlecrystal techniques ranging from routine crystal structure determination totwinned and/or disordered crystals.

2. Synthesis, structural and spectroscopic characterization, and magneticstudies of molecular magnetic materials in collaboration with other nationaland international research groups.

Activities and Achievements:Heterometallic 3d-4f metal clusters play a significant role in molecular magnetismbecause the combination of paramagnetic 3d ions with highly anisotropic trivalentlanthanides may lead to interesting magnetic materials. As part of our researchprogram on molecular magnetism and spectroscopy of 3d-4f clusters we reported adinuclear [FeIIGdIII{pyCO(OEt)pyCOH (OEt)py}3](ClO4)2 (1) and a trinuclear[FeII

2GdIII{pyCO(OEt)py}4(NO3) (H2O][Gd(NO3)5]0.5(ClO4) (2) heterometallic cluster("Expanding the 3d-4f heterometallic chemistry of the (py)2CO and pyCOpyCOpyligands: structural, magnetic and Mössbauer spectroscopic studies of two FeII-GdIII

complexes", A.N.Georgopoulou, R.Adam, C.P.Raptopoulou, V.Psycharis, R.Ballesteros,B.Abarca, A.K.Boudalis, Dalton Transactions, 40 (2011) 8199-8205) synthesizedunder anaerobic conditions. X-ray crystallography revealed that bridging betweenthe metal ions is achieved by the alkoxo oxygen atoms of the ligands.

1 2


Mössbauer spectroscopy of 2 revealed parameters typical of high-spin iron(II) inoctahedral N/O environments (δ1=1.14 mm s-1, ΔΕQ1=3.55 mm s-1, Γ1/2(1)=0.14 mm s-1

and δ2=1.11 mm s-1, ΔΕQ2=2.74 mm s-1, Γ1/2(2)=0.13 mm s-1). Both Fe atoms exhibitsimilar, but not identical, N3O3 coordination spheres, which cannot be discriminatedwithin this technique. Magnetic susceptibility studies in polycrystalline samples of 1and 2 revealed very weak ferromagnetic interactions between the metal ions (1:JFeGd=+0.68 cm-1, DFe=12.0 cm-1, g=1.99; 2: JFeGd=+0.03 cm-1, JFeFe=-1.73 cm-1,g=1.98;according to the –JSiSj spin-Hamiltonian formalism). Magnetization isotherms at 2Krevealed saturation above ~5T at 10.30 NAB for 1, and absence of saturation for 2,even at 9T, suggesting the presence of low-lying excited states.

In collaboration with the group of Prof. Perlepes (University of Patras) we reportedanalogous heteronuclear clusters Ni2Ln (Ln = Gd, Tb, Dy, Y) ("Triangular NiII2LnIII andNiII2YIII complexes derived from di-2-pyridyl ketone: Synthesis, structures andmagnetic properties" A.N.Georgopoulou, C.G.Efthymiou, C.Papatriantafyllopoulou,V.Psycharis, C.P.Raptopoulou, M.Manos, A.J.Tasiopoulos, A.Escuer, S.P.Perlepes,Polyhedron, 20, (2011) 2978-2986).In the field of molecular magnetism, chemical reactivity of preformed clusters as arational synthetic route to alter the physical properties has been widely used. In thatrespect we reported the isostructural complexes [Ni9(N3)2(O2CMe3)8{(py)2CO2}4] (3)and [Co9(N3)2(O2CMe3)8{(py)2CO2}4] (4) ("The first non-acetato members of thebis(anion)octacarboxylatotetrakis{di-2-pyridyl-methanediolate(-2)}enneametal(I I)family of complexes: Synthesis, X-ray structures and magnetism of[M9(N3)2(O2CMe3)8{(py)2CO2}4] (M = Co, Ni)" Th.C.Stamatatos, C.P.Raptopoulou,S.P.Perlepes, A.K.Boudalis, Polyhedron, 30 (2011) 3026-3033) which are analogous tothe previously well studied acetato analogues. X-ray crystallography revealed thatboth clusters consist of two MII

4 squares stacked parallel to each other in a slightlystaggered conformation, with a ninth octacoordinate MII ion between them.; thelatter feature is extremely rare in NiII and CoII chemistries. A salient feature of bothstructures is the two end-on azides bridging the four metal ions in the square bases.

3 4


Magnetic studies from crystalline samples of 3 revealed antiferromagneticinteractions between the metal ions leading to a diamagnetic ground state, insteadof an S=9 ground state for the acetate analogue of 3. Analogous studies for 4 alsoshowed remarkable differences in the magnetic behavior between 4 and its acetateanalogue, indicating that possible electronic effects of the carboxylate alkyl group onmagnetic exchange is an issue deserving further theoretical study.Another area of our research interest involves investigation of the syntheticparameters that may affect the identity of the product(s) from a given reactionsystem and establishment of structure-properties relationships. Within this respect,we examined the role of the reaction solvent, the reactants' stoichiometry, thenature of the anion in the metal salts, the presence of base and/or counterions, thepresence of co-ligands and the crystallization method to the chemical identity of theproducts from a certain reaction system. We isolated the monomer complex[Cu(Hsalox)2] (5), which constitutes the repeating unit of the 2D network[Cu(Hsalox)2]n (6), as well as complexes [Cu3(salox)(L1)(L2)] (7), [CuCl(L1)] (8) and the3D network [Cu2Na(O2CMe)5(HO2CMe)]n (9), where ligands L1

- = o-O-C6H4-CH=NO-C(CH3)=NH and L2

3- = o-O-C6H4-CH=NO-C(o-O-C6H4)=N were formed in situ("Copper(II)-mediated oxime-nitrile coupling in non-aqueous solutions: Synthetic,structural and magnetic studies of the copper(II)-salicylaldehyde oxime reactionsystem", K.N.Lazarou, A.K.Boudalis, V.Psycharis, C.P.Raptopoulou, InorganicaChimica Acta, 370 (2011) 50-58).

The most exciting findings of our work include the different (de)protonation state ofthe ligand in 5-7, the coordination versatility of its mono- and di-anionic form in thestructures of 5-7, and the rich reactivity of its {C=NO} fragment which affordedligands L1

- and L23- in situ. The magnetic susceptibility measurements for the 2D

network 7 revealed the presence of weak ferromagnetic interactions between theadjacent CuII ions (J = +0.36 cm-1, ˆ ˆ i jH JS S ), whereas initial evaluation for the 3Dnetwork 9 revealed antiferromagnetic interactions along with ferromagneticinteractions via the diamagnetic bridges (J = -360 cm-1, zj = +20 cm-1,

ˆ ˆ ˆ( ) i j z zH JS S zJ S S ).

The total outcome of the research activities is: 27 publications in Refereed Journals 3 conference presentations 1 Invited Lecture Currently one program (1) is active and concerns services

6 7 9


Published Conference Proceedings

Other Publications

Active Externally Funded research ProgramsFunding Research Program, “Structural study and characterization ofcrystalline materials” (services), (GEL #813), 2010-2013, 18.000 €

Conference Organisation

Conference ParticipationPsycharis, V.4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsJune 2011, Patras, GreeceRaptopoulou, C.P.4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsJune 2011, Patras, GreeceBoudalis, A.K.4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsJune 2011, Patras, GreeceGeorgopoulou, A.N.4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsJune 2011, Patras, Greece

Invited TalksBoudalis, A.K. Georgopoulou, A.N., Sanakis, Y., Margiolaki, I., Psycharis, V.,Raptopoulou, C.P."Dynamic Effects in Basic Iron(III) Carboxylates: Magnetic Relaxation and MagneticJahn-Teller Effect in [Fe3O(O2CPh)6(py)3]ClO4∙py"4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsJune 2011, Patras, Greece

Teaching and Training ActivitiesName: Dr. V. Psycharis.Lesson Title, Dates/Duration of lectures: Powder X-ray Diffraction, 5 dayAcademic Institute: post-graduate programs "Physics and TechnologicalApplications" and “Microsystems and Nanodevices” at the Faculty of AppliedMathematics and Physics of the National Technical University of Athens, PracticalLaboratory exercise,Dr V. V. Psycharis is the Supervisor of the Post-Graduate Student Program of IMSsince 2000 and Member of the Graduate Student Program Supervisor Committee ofNCSR “Demokritos”.


Doctoral Dissertations completed in 2011Georgopoulou, A.N.Dissertation Title: "Synthesis, structural characterization, spectroscopic andmagnetic studies of polynuclear 3d homometallic and 3d-4f heterometalliccomplexes"Research Supervisor at NCSR: Raptopoulou, C.P.University where the Thesis was presented: University of Patras


NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

Research Director: G. PapavassiliouPermanent Research Staff: M. FardisContract Researchers: E. KarakostaPost-Doctoral Researchers: G. DiamantopoulosVisiting Researchers: Dr. A. DouvalisPhD Candidates: D. Koumoulis, N. Panopoulos, D. TsitrouliMasters Students:External Collaborators: Dr. M. Belesi, Prof. D. Argyriou, Prof. J. Gallias,

Prof. J. Dolinsek, Prof. D. Panagiotaras

Areas of Research:

The basic research includes applications of 1D and 2D Nuclear Magnetic Resonance(NMR) and Nuclear Quadrupole Resonance (NQR) techniques in Strongly CorrelatedElectron, magnetic, superconductive and nanostructured systems, such as ColossalMagnetoresistive (CMR) manganese perovskites, magnetic nanoparticles, carbonnanotubes etc. The applied research involves the development of state-of-the-artNon-destructive testing (NDT) methodologies, which includes Acoustic methods, andNuclear Magnetic Resonance (NMR) portable devices for examining the performanceand physicochemical properties of porous materials such as cement, mortars andconcrete as well as metal structures.

Activities and Achievements:1. Decoration of Carbon Nanotubes with CoO and Co nanoparticles

In this project, the decoration of carbonnanotubes with CoO nanoparticles andthe transformation of CoO in metalliccobalt through thermal treatment underreducing atmosphere weredemostrated. The method is facile,based on environmental friendly rawmaterials, inexpensive, andreproducible for the large-scalesynthesis of analogous compositenanomaterials. These hybrid structuresmay combine the applications of thebare nanotubes structures andpotentially enhance their propertiesgiving considerable impact on thepotential applications of nanotubes. Inthis project it is shown through

(a) A comparison between the 59Co NMR spectrafor composite materials as measured at 300 K. (b)59Co NMR spectra at selected temperatures. Theinset shows the temperature dependence of theLarmor frequency L, for the composite materials.

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Comparison of NMR and MIPdistribution profiles at selectedhydration times for (a) CaIG5 and(b) CaIG7.

T1 contour plots and T1 distribution profilesvs. hydration time for CaIG5 (a and b) andCaIG7 (c and d).

magnetic characterization that the as-synthesized sample is composed of CoOnanoparticles. In the annealed samples, the presence of ferromagnetic Co isdetected by magnetic and NMR measurements. The NMR measurementsdemonstrate the allotropic phase transformation of nanometric Co particles in theannealed samples and provide evidence for slow fluctuations of uncompensatedspins in CoO nanoparticles which are still present in the sample annealed at 500◦C.

2. Application of 1H NMR in hydration and porosity studies of lime-pozzolanmixtures

The simultaneous monitoring of hydration and porosity evolution in freshlysynthesized mortars is a key issue for assessing their performance and adjusting theircompositional and curing parameters.

In this work, 1H NMR relaxation is applied to lime -pozzolan mixtures to monitor in

real time the hydration and porosity evolution during setting. We demonstrate thatby using a portable, low field (0.29 T) Halbach magnet it is possible to study in detail,the evolution of the pore structure of the mixtures. By measuring the 1H NMR spin–lattice relaxation T1 it was possible to distinguish between different pore populationswithin the system (at different setting periods), and to study the growth of the

hydrated phases.

3. Attachment of Pseudomonas putida ontodifferently structured kaolinite minerals: Acombined ATR-FTIR and 1H NMR study

The attachment of Pseudomonas (P.) putidaonto well (KGa-1) and poorly (KGa-2)

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crystallized kaolinite was investigated in this study. Attenuated Total ReflectionFourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance wereemployed to study the attachment mechanisms of P. putida. It was shown thatelectrostatic interactions and clay mineral structural disorders can influence theattachment capacity of clay mineral particles.

4. Development of Non-destructive Testing and Evaluation (NDT&E)Methodologies and Devices for the construction field.

In the context of two large European projects state-of-the-art NDT methodologieswere developed for in situ monitoring large scale structures. In particular,microseismic and impact echo methods (at frequencies 1 - 60 kHz), multifrequencyultrasonic testing (50 kHz – 500 kHz), together with a high sensitive portable NMRsensor was developed for exploring water content and cement porosity in order togain critical information concerning the performance, damage risk, and conditionmonitoring of civil engineering infrastructures including concrete and metals.

Microseismic device

The implementation of the FK methodology in a state of the art, portable device wasmainly assembled from acoustic modulus. This device, in conjunction with theadvanced signal analysis can be used for in field microseismic measurements inweathered or delaminated concrete and metal structures.

Portable NMR device

The implementation of a state of the art,portable, solid state NMR spectrometerwas assembled from solid stateelectronic modulus. This spectrometer, inconjunction with a portable permanentmagnet can be used for in field NMRmeasurements of core drilled samples.The main specifications of the NMRspectrometer are the following:1) Low applied magnetic field in order toreduce magnetic susceptibilitydifferences between the solid phase and Central part of the portable NMR

spectrometer arranged in three differentlayers

Portable microseismic device


the fluid filling the pore space in NMR experiments in porous materials.

2) High signal to noise ratio and fast recovery for the detection of the weak NMRsignals with short relaxation times encountered in the NMR experiments of porousmaterials and particularly of core drilled samples which contain many paramagneticimpurities.

3) Simple self-contained apparatus of small size and low weight for portability.The portable broadband NMR spectrometer was coupled to a circular Halbach arraymagnet, which provides a uniform field in a compact format and is capable of low-field NMR measurements. The magnet is fully insulated and temperature stabilized,providing a constant magnetic field over a wide range of sample and roomtemperatures.

Active Externally Funded research Programs

1. EUREKA-EUROSTARS, “Integrated Portable Diagnostic Tool for Non-DestructiveEvaluation of Large Scale Concrete Structures”, 2009-2012, 80,000 Euro.

2. FP7-SME-2010-1, “DIAGNORAIL-Combining innovative portable VISUAL, ACOUSTIC,MAGNETIC, and NMR methods, with in-situ CHEMICAL diagnostic tools for effectivefailure assessment and maintenance strategy of RAIL and subway systems”, 2011-2012,329,000 Euro.

3. IKYDA 2010-2011, “The study of Mott Insulators with Orbital Degrees of Freedom byusing Neutron Scattering and Nuclear Magnetic Resonance (NMR) techniques”, 9,600Euro


1. Fardis, M.1st Summer Symposium on Nanomaterials and their application to Biology and MedicineStructural, Magnetic and Spectroscopic Investigations of Iron Oxide (maghemite)nanoparticles. Application in Magnetically Induced Hyperthermia.13th-16th June 2011, Poznan, Poland.

2. G. Papavassiliou, N. Panopoulos, D. Koumoulis, M. Fardis, M. Pissas.Euromar 2011: Magnetic Resonance Conference.21st-25th August 2011, Frankfurt, Germany.

Halbach magnet with the core drill sample inside.


3. Diamantopoulos, G.Fourth North America-Greece-Cyprus workshop on paramagnetic materials.Patras Greece, June 14-18, 2011.

Doctoral Dissertations completed in 2011Name: D. KoumoulisDissertation Title: Nuclear Magnetic Resonance Spectroscopy in strongly electron correlatedtransition metal oxides exhibited intrinsic nanophase regionsResearch Supervisor at NCSR: G. PapavassiliouUniversity where the Thesis was presented: National Technical University of Athens.


HEAVY FERMION SYSTEMS

Research Director: Evagelia MoshopoulouPermanent Research Staff: Evagelia MoshopoulouVisiting Researchers: Marija MaletinExternal Collaborators:Kate Page, Vladimir Srdic, Joe D. ThompsonAreas of Research:Structural Studies of correlated Electron Materials and Nanoparticles

Activities and Achievements:

Subject 1:Evolution of the structure and physical properties as a function of composition andsize in ferrite nanoparticlesNames:Evagelia G. Moshopoulou (IMS), Marija Maletin (IMS), U. Novi Sad), Eamonn Devlin(IMS), K. P. Giannakopoulos (IMS), D. Stamopoulos (IMS), K. Eleftheriadis (IΠTA)Aim:Some of the most interesting and challenging issues of the science of magneticnanoparticles are the development of new electronic, optical or photochemicalproperties and the optimization of their magnetic properties. Among the widevariety of magnetic nanoparticles available for modification, spinel ferritenanoparticles are among the most attractive systems. The spinel structure iscomplex and adaptive compared to the crystal structure of other magneticnanoparticles (elemental, intermetallic, oxides) and thus it can be modified invarious ways, resulting in novel or enhanced physical properties.In spinel ferrites, with the general formula (M1-δFeδ)[MδFe2-δ]2O4, where M is a cationand δ is the inversion parameter, the cubic close-packed structure is formed ofoxygen ions with cations occupying the tetrahedral (A) and octahedral [B] interstitialsites of the spinel cell (A)[B]2O4. The spinel structure is characterized by threedegrees of freedom: (i) the lattice parameter, a; (ii) the anion parameter, u; and (iii)the cation inversion parameter, δ. For spinel nanoparticles, these degrees offreedom (and concomitantly their physical properties) can be modified controllablyby changes to the preparation method, particle size or shape, by doping, byprocessing, by pressure, temperature, magnetic or electric field. Besides theseparameters, in spinel ferrites the cation distribution between the two interstitialsites of the structure has a strong influence on the magnetic properties whichoriginate from the magnetic moments of their unpaired electrons, coupled bysuperexchange interactions via the oxygen anions.

Our plan is to exploit the flexibility, the complexity and the adaptability of thespinel cell in order to modify the structure and composition of spinel nanoparticles


and thus to enhance their electronic and/or magnetic properties. Our goal is toestablish the size-composition-structure-property relationship and to identifypromising functional materials for applications.

Among the spinel oxides, there is a great interest in ZnFe2O4 and doped-ZnFe2O4

nanoparticles. Besides the fundamental scientific interest, these materials haveimportant existing applications in such diverse fields as energy, medicine andenvironment.

Results:The present study was undertaken against the above background. It is focused

on Zn1-xInxFe2O4 and ZnYxFe2-xO4 nps with 0 x 0.6 and explores the effect ofcomposition and size on the above degrees of freedom of their spinel structure andconcomitantly on their magnetic properties.

Nanoparticles of ZnFe2O4 and doped derivatives Zn1-xInxFe2O4 and ZnYxFe2-xO4 (0 x 0.6), were synthesised by a low temperature wet-chemical method (co-precipitation) and characterised by conventional powder X-ray diffraction,Transmission Electron Microscopy, Mössbauer and Raman spectroscopies and SQUIDmagnetometry. Additional experiments had been conducted using a SMPSspectrometer in order to measure the number size distribution of the generatednanoparticles. The results suggested that more than 85% of the nanoparticles werein the range of 10-50nm. It was found that, while the average spinel structure ismaintained for all compositions and sizes investigated, there is cation re-distributionon the tetrahedral and octahedral sites of the spinel cell of the nanoparticlescompared with the normal spinel cell of the bulk ZnFe2O4. Therefore, the co-precipitation technique yields single phase, partially inversed spinel Zn-ferritenanoparticles. Regarding their magnetic behavior, they exhibit the magneticproperties of a collection of single domain nanoparticles, with superparamagnetismabove a blocking temperature of about 25 K (which varies slightly with thecomposition and size) and ferrimagnetism below this temperature. Our studiesrevealed that size, composition, and concomitant structural rearrangementsinfluence the Fe-O-Fe superexchange interactions and consequently the magnetismof ZnFe2O4 nanoparticles and In- or Y- doped derivatives obtained by co-precipitationmethod.

Subject 2:Synthesis and characterization of silica core/nano-ferrite shell particlesNames:Evagelia G. Moshopoulou (IMS), Milan P. Nikolić (University of Novi Sad, Serbia), K. P.Giannakopoulos (IMS), D. Stamopoulos (IMS)Aim:At present, major challenges for the preparation of nanoparticle systems include thedevelopment of new compositions and the fabrication of multifunctional systemswith specific architectures. In such systems, silica has been very often utilized as atemplate for the assembly of different functional nanoparticles. Special attention hasbeen directed to properly coated or surface-modified particles, which can offer ahigh potential for numerous applications, due to the change of their interfacialcharacteristic and to their novel electrical, magnetic or optical properties. In


addition, incorporation of another layer of magnetic nanoparticles between the silicacore and the mesoporous silica shell can improve particle separation and make itrapid and highly efficient. The first step in the development of such a specificarchitecture is the preparation of the silica core with the appropriate magnetic shell.Given that sufficiently small ferrite magnetic nanoparticles are single-domainmagnets and exhibit superparamagnetic behavior above their blocking temperature,they can be used for the formation of the shell. Each individual ferritesuperparamagnetic nanoparticle has a constant magnetic moment and, while themoments of an assembly of such magnetic nanoparticles can be oriented in anapplied field, they have no net magnetization in zero-field. These features makesuperparamagnetic nanoparticles very attractive systems for a broad range ofbiomedical applications, because the risk of magnetically induced aggregation isnegligible at RT. Magnetic nanoparticles have been already widely used in variousaspects in biotechnology and bioengineering such as cell separation, immobilizedenzymes, isolation and purifications of proteins, magnetic drug targeting andantibody immobilization. Regarding the synthesis of core/shell nanoparticlesextensive research has been devoted. In this work, monodispersed silica spheres,synthesized by the Stober method, were used as templates for assembly of ferritenps synthesized from nitrate solutions.

Fig 1: TEM images of as-synthesized particles (prepared with APTES-functionalizedsilica, at pH = 7 with ferrite/silica weight ratio WR = 1/4).

Results: We could sythesize core/shell particles by assembling oppositelycharged ferrite (Fe3O4 or NiFe2O4) nanoparticles on the surface of monodispersedsilica core particles (having size ≈0.4 mm) prepared by hydrolysis and condensationof tetraethylortosilicate. Optimal conditions for synthesis of silica core/ nano-Fe3O4

shell particles were found at pH ≈5.4. The obtained particles havesuperparamagnetic behavior above a blocking temperature of 25 K, which makethem very attractive for a broad range of biomedical and bioengineeringapplications. Incorporation of nickel into ferrite structure could not be achieved atlower pH value, so functionalization of core particles was required. Incorporation ofnickel into ferrite structure was successful at pH above 7, however at higher pH theformation rate of nickel–ferrite particles becomes very fast and the self-aggregation


dominates the competing formation of the nickel–ferrite shell. Because of that, theself-aggregation was prevented by surface modification of nickel–ferritenanoparticles with citric acid before their deposition on the functionalized silica coreand homogenous and continuous NiFe2O4 shell was finally obtained.

Publications“Probing the Transition from Nano- to Bulk-Like Behavior in ZnFe2O4 Nanoparticles”,E. G. Moshopoulou, O. Isnard, M. Milanovic, V. V. SrdicMaterials Science Forum 674, 207 (2011).

Programs1. Funding Agency: EU FP7Program: Cooperation in Science and Technology (COST); Action “Materials, Physicsand Nanosciences”Project title: “Single- and Multiphase Ferroics and Multiferroics with RestrictedGeometries (SIMUFER)”; 02/03/2010 through 01/03/2014Member of the Management Committee and the National Representative.

2. Funding Agency: GSRTProgram: ThalesProject title: “Preparation, Structural Characterization and Physical Properties ofNanostructured Multifunctional Materials” 1/10/2011 through 31/9/2015

Participation at conferencesTalk: “On the processing and properties of nanostructured single- and multiphaseferroics and multiferroics: Strengths, needs and joint initiatives” COST Meeting,Bordeaux, France, June 30th - July 1st, 2011

Active Externally Funded research ProgramsFunding Research Program, “Project Title”, Duration, Funding

1. EU FP7Cooperation in Science and Technology (COST); Action Materials,Physics and Nanosciences, “Single- and Multiphase Ferroics and Multiferroicswith Restricted Geometries (SIMUFER)”; 02/03/2010 through 01/03/2014.

2. GSRT - Thales “Preparation, Structural Characterization and PhysicalProperties of Nanostructured Multifunctional Materials” 1/10/2011 through31/9/2015

Conference ParticipationName: Evagelia MoshopoulouConference Title: COST Meeting, Bordeaux, France, June 30th - July 1st, 2011.Presentation: “On the processing and properties of nanostructured single- andmultiphase ferroics and multiferroics: Strengths, needs and joint initiatives”Conference dates, location: June 30th - July 1st, 2011, Bordeaux, France


COMPUTATIONAL MATERIALS SCIENCE

Research Director: K. TrohidouPermanent Research Staff: K. TrohidouContract Researchers: M. VasilakakiPost-Doctoral Researchers: K. SimseridisPhD Candidates: G. Margaris

External Collaborators:

Prof. JA Blackman. Department of Physics, University of Leicester,UK, Prof. C.Binns. School of Physics, University of Leicester,United Kingdom, Dr. D. Fiorani.Instituto Struttura della Materia- CNR,Rome, Italy, Prof. T. Dietl. Institute ofPhysics, Police Academy of Sciences, Warsaw, Poland, Dr. J. Nogues. InstitucióCatalana de Recerca i Estudis Avançats (ICREA), and Institut Català deNanotecnologia (ICN), Barcelona, Spain, Prof. H. Kachkachi. Lab. deMathematiques, Physique et Systemes (LAMPS) Universite de Perpignan,Perpignan France, Prof. M Velgakis, Polytechnic School, Univ. of Patra, Greece,Prof. L. Lanotte and Dr. V. Ianotti. Coherentia—INFM and Dipartimento di ScienzeFisiche, Università degli Studi di Napoli, Italy, Dr Gang Chen, Johannes KeplerInstitute of Semiconductor and Solid State Physics, Johannes Kepler University,Linz, Austria.

Activities and Achievements:Our research activities this year have been focus in the study of nanostructuredmagnetic semiconductors of the type Ga1-xMnxN and in the study of simple andcomplex magnetic nanoparticles and their assemblies.Study of simple nanoparticles and their assembliesa1)Recently a great interest is focused on the magnetic behaviour of ultra-smallnanoparticles (3 nm) CoFe2O4 because of scientific and technological reasons. Themagnetic properties of cobalt ferrite particles in combination with their small sizemake them suitable for their use in ordered nanostructured superlattices while theirhigh surface to volume ratio gives the opportunity for studying the effects of thespin-glass like surface on the magnetic behaviour.In collaboration with Drs Dino Fiorani and Davide Peddis from the Instituto diStruttura della Materia–CNR, Roma, Italy, we have employed the Monte Carlosimulation technique to study the aging effect on the Zero-Field-Cooled (ZFC)magnetization curves of ultra-small CoFe2O4 nanoparticles (mean size ~ 3 nm)embedded in a Si matrix. We consider spherical nanoparticles consisting of anordered ferrimagnetic core and a ferrimagnetic disordered surface. Our simulationsshow that the spin-glass like disorder at the surface affects the magnetic propertiesto the extent that they exhibit an aging effect: the low temperature ZFCmagnetization depends on the time (waiting time, tW) spent before applying themagnetic field at a temperature at which most of the surface moments are frozen.


The results of our MC simulations are in good agreement with the experimentalfindings confirming that the random freezing of surface spins is responsible for theaging effect.

a2) In the assemblies of magnetic nanoparticles the crucial role of interparticleinteractions in determining their response to an applied field and temperature hasbeen recognized long ago. When the interparticle interactions become significantthe system displays a rich variety of magnetic configurations resulting from thecompetition between the different energy terms.In collaboration with Dr D. Fiorani from Rome and the team of Prof. L. Lanotte(University of Naples) we have studied the role of interparticle interactions in themagnetic behavior of dense assemblies of Fe nanoparticles with concentration wellabove the percolation threshold using the Monte Carlo simulations technique withthe implementation of the Metropolis algorithm. The initial magnetization as afunction of the applied field as well as the temperature dependent zero field cooledand field cooled (ZFC/FC) magnetization curves have been calculated for differentconditions of the assembly’s morphology and the interparticle interaction strengths.Our simulations showed that the magnetic behavior of the assembly is mainlydetermined by its morphology. Strong competition between the anisotropy energyand exchange energy in a non-uniform assembly of nanoparticles (NPs) results in afrustration of the NPs moments coupling and creates plateaus and abrupt steps,which indicate a sudden collective spin reversal. The numerical results are inagreement with experimental findings.

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T(J/KB)

Fig.1 (left) Monte Carlo simulations and (right) Experimental results of ZFCreference curve(full circles) and ZFC memory curve after waiting tw(emptycircles), (insets) percentage of the relative difference DM between memoryand reference curve as a function of temperature.


Study of complex nanoparticles and their assembliesb1) Recently, bi-magnetic core/shell nanoparticles, where both core and shell areeither ferromagnetic (FM), ferrimagnetic (FiM) or antiferromagnetic (AFM), arebecoming increasingly appealing. The synergetic combination of the properties ofthe two constituents and their interactions (e.g., in hard/soft FM spring magnets orexchange biased FM/AFM) can enhance their performance. In fact, promising resultsshowing enhanced blocking temperatures, increased energy products, superiormicrowave absorption or optimized hyperthermia, have already been demonstrated.Other potential applications also include nanoscale magnetic quantum-dot cellularautomata or miniaturized spin transport devices.We have studied in collaboration with the research group of Prof. J. Nogués of ICREAand Catalan Institute of Nanotechnology, the magnetic behavior of non-interactingFe3O4/Mn3O4 soft core /hard shell nanoparticles with a discontinuous shell wherethe two phases couple antiferromagnetically. Our results show that theantiferromagnetic interface coupling allows the control of the sign and themagnitude of the loop shift and the coercivity by the cooling field. Concerning thetemperature dependence of the magnetization M(T) our results show that for lowcooling fields M(T) exhibits a downturn at critical temperature of the shell, while forlarge fields there is an upward turn at this critical temperature.

b2) Taking into account that most of the applications of bi-magnetic core/shellnanoparticles (e.g., magnetic recording or permanent magnets) should involve largenumbers of particles there is an increasing need to simulate arrays of core/shellnanoparticles.

0.0 0.2 0.4 0.6 0.8 1.00.0

0.2

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1.0

g=0.1 g=0.5 g=0.8

Mz/

Ms

h

(a)

0.0 0.1 0.2 0.3 0.4 0.50.0

0.1

0.2

0.3

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0.5

0.6

Mz/

Ms

h

g=0.1 g=0.5 g=0.8

(b)

Fig. 2 An assembly of Fe nanoparticles interacting with 3 different dipolar interaction strengths(p=0.5) (a) Initial Magnetization curves (virgin curves) at temperature T=0.005 (b) ZFC curves forthe assembly under cooling field Hcool=0.05

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(d)(c)

(b)

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H (J/gμB)

(a) core + core IF + core surf shell + shell IF + shell surf

M Z

H (J/gμB)

HE

HCH E, HC

(J/gμ

B)

HFC (J/gμB)

0.4 J/μB

0.7 J/μB

4.0 J/μB

M Z

T (J/kB)

TC(shell)

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(a) core + core IF + core surf shell + shell IF + shell surf

M Z

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HE

HCH E, HC

(J/gμ

B)

HFC (J/gμB)

0.4 J/μB

0.7 J/μB

4.0 J/μB

M Z

T (J/kB)

TC(shell)Fig.3 (left) Hysteresis loop of the magnetization and in the inset the schematic representationof the simulated soft core/hard core ferrimagnetic nanoparticle, red denotes core surfaceatoms, green shell and blue surface, respectively. (right) Cooling field dependence of thecoercivity, HC, and exchange bias, HE.


In collaboration with Prof. Nogues from Barcelona, Spain, we have developed a novelmesoscopic method based on a Monte-Carlo approach to easily simulate largeensembles of bi-magnetic core/shell nanoparticles by reducing the number of spinsto be simulated to the minimum necessary to satisfactorily represent their magneticstructure and introducing the adequate exchange parameters between them. Thevalidity of the model has been demonstrated by studying the effect of exchangeinteractions on the exchange bias of Co/CoO (FM/AFM) core/shell nanoparticles withexcellent agreement with experimental results. The experimentally observedevolution of the magnetic properties (i.e., HE, HC, TB) of large 2D random arrays ofCo/CoO nanoparticles have been satisfactorily simulated. Moreover, the fact thatexchange and dipolar interactions can be controlled independently in the model hasclearly highlighted the dominant role of exchange interactions in the Co/CoO system.Importantly, the proposed mesoscopic approach can be easily extrapolated to thestudy of the magnetic and magnetotransport properties of other bi-magneticsystems by the proper choice of the minimum number of spins characterizing thesystems and their interactions.

Conference OrganisationTrohidou, KN

20ου International Conference on Soft Magnetic MaterialsMember of the International Advisory Committee and the Local OrganisingCommittee, Kos , 18-20 September, 2011

Conference Participation and PresentationsVasilakaki, M., Margaris, G., Trohidou, K. N.Interplay of internal characteristics and interparticle interactions in the magneticbehaviour in nanoparticle assemblies (oral)Soft Magnetic Materials (SMM20)18-22 September, 2011, Kos Island, Greece

-3 -2 -1 0 1 2 3-0,6

-0,4

-0,2

0,0

0,2

0,4

0,6

Dense

MZ/M

S

H

Co/CoO

Disperse

Fig. 4 (left) Schematic representation of the spin structure and intraparticle and interparticle exchangeinteractions utilized in the simulations. (right) Simulated at T = 0.02 normalized hysteresis loops of 2Drandom arrays of Co/CoO core/shell nanoparticles with densities xV=0.08(Dispersed) and 0.33 (dense).


Trohidou, K. N., Vasilakaki, M., Peddis, D., Fiorani, D.Memory effects in ultra small CoFe2O4 Nanoparticles (poster)Soft Magnetic Materials (SMM20)18-22 September, 2011, Kos Island, Greece

Vasilakaki, M., Trohidou, K. N., Nogues, J.Study of the exchange bias effect in doubly inverted core/shell nanoparticles(poster)Soft Magnetic Materials (SMM20)18-22 September, 2011, Kos Island, Greece

G. Margaris, K.N. Trohidou and H KachkachiInterplay between single particle surface anisotropy and dipolar interactions inmagnetic nanoparticle assemblies.Workshop on Dynamics of Nanomagnets Assemblies,7-8 Nov. 2011, Perpignan, France.

Invited TalksTrohidou, KNMonte Carlo Study of the exchange bias effects in doubly inverted core/shellnanoparticles.Workshop on Dynamics of Nanomagnets Assemblies,7-8 Nov. 2011, Perpignan, France.

Teaching and Training ActivitiesVasilakaki, M.Self-Organized Magnetic NanostructuresSummer School of National Center of Scientific Research ‘Demokritos’4-15 July, 2011, Athens, Greece

Research ConsultationTrohidou KNReferee for FP7 ERA-NET Grants Period 201


THEORETICAL PHYSICS OF MULTIELECTRON AND MAGNETIC SYSTEMS

Research Director: S. ThanosPermanent Research Staff: S. ThanosContract Researchers: A. K. TheophilouPost-Doctoral Researchers: -Visiting Researchers: -PhD Candidates: 1. Iris Theophilou

2. Maria Tassi3. Aristi Christofi

External Collaborators:Vitaly Glushkov, University of Dniepropetrovsk, UkrainePanagiotis Moustanis, TEI of PiraeusNikitas Gidopoulos, Rutherford-Appleton, Laboratory, EnglandMiroslaw Labuz, Univerisity of Rzeszow, Poland

Areas of Research:Methods of Many-electron systems. Advances in the mathematical theory of themany-particle quantum mechanics, make it possible nowadays to determine theproperties of atoms, molecules and solids with sufficient accuracy. Unfortunately,existing techniques are not applicable for large systems. For this purpose one has toresume to approximation methods. Such methods, based on mathematicaltheorems, have been developed by our group. Our methods include excited statedensity functional theory, direct mapping optimized effective potential theory andspin projected Hartree-Fock for the ground and excited states. In addition, usingopen sources computational packages we try to determine the properties of solidmaterial (bulk and layers) with and without impurities. For Heisenberg Hamiltoniansa method based on a hierarchy of spin algebras has been developed and applied tospin rings with calculation giving results close to those measured experimentally.Anisotropic Photonic Nanocomposite Materials: We make detailed calculationsusing the layer-multiple-scattering method, in order to examine the opticalproperties of photonic crystals consisting of chiral spheres as well as spiral staircasestructures consisting of metallic nanorods.

Activities and Achievements:a) Methods of Many-electron systemsI) Development of mathematical and computational techniques for ab initio

calculations of properties of atoms, molecules and solidsThe single Slater determinant approximations to the ground state of many-

electron problem (e. g Hartree-Fock, Density Functional Theory) are noteigenfunctions of all operators that commute with the exact Hamiltonian of thephysical systems under consideration, although the exact solution of the Schrödingerequation have such properties. Knowledge of the exact symmetry of the energy


eigenstates allow us to determine selection rules for transitions to excited states andthe possible allowed transitions. For this purpose, we used the unrestricted Hartree-Fock (UHF) ground state to extract wave functions having the proper total spinsymmetry and improved energy. The advantage of the approximation is its low cost,since one can use already existing data on UHF calculations. Also, this approach givesbetter results in energies than those obtained by UHF. We test our methodology bymaking applications to molecules as one can see in the figure 1.

The usual approximation method to the excited states is to create a particle hole pairfrom the energy orbitals. In the present formulation the particle hole pair orbitalsare chosen by a minimization method, i.e., we minimize the functional <Φ|Η|Φ>where |Φ>=α+

ναoc|Φ0>, α+ν is the creation operator corresponding to a spin orbital

in the space of virtual space and αoc the annihilation operator corresponding to aspin orbital in the space of occupied states. The excited states we obtain are not onlymutually orthogonal but also orthogonal to the ground state. The advantage of thismethod is that can obtain a good approximation for the excitation energies without

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E1/21/2

ERHF

LiO

E (

hart

ree)

R (a.u.)

(a)

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ree)

R (a.u.)

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E1/21/2

ECI

(b)

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E1/21/2

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E (

hart

ree)

R (a.u.)

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E1/21/2

EROHF

NH2

E (

hart

ree)

R (a.u.)

(c)

E (

hart

ree)

R (a.u.)

EUHF

E1/21/2

ECI

(d)

EUHF

E1/21/2

EROHF

E (

hart

ree)

R (a.u.)Figure 1: Total molecular energy versus internuclear separation of: a) , b) LiO and c), d) NH2


requiring time consuming calculations. We tested the accuracy of our methodologyby evaluating the excitation energies for atoms and molecules.

Table 1: Excitation energies for the second excited state from the ground state

Table 2: Excitation energies for the third excited state from the ground state

Table 3:

Excitation energies from the ground state of the first two excited states for BeH andCH at the equilibrium distances 2.5 Bohr and 2.12 Bohr respectively

Atom Ground stateSecond

excited state

Excitationenergy

(hartree)

Excitation energy(experimental)

(hartree)Li 1s22s1 1s23s1 0,12 0,12N 1s22s22p3 1s22s22p23p1 0,44 0,45

F 1s22s22p5 1s22s22p43p1 0,56 0,54

Ne 1s22s22p6 1s22s22p53p1 0,68 0,67

Na 1s22s22p63s1 1s22s22p64s1 0,11 0,12

Atom Ground stateThird excited

state

Excitationenergy

(hartree)

Excitation energy(experimental)

(hartree)Li 1s22s1 1s23p1 0,15 0,14N 1s22s22p3 1s22s22p24s1 0,46 0,47

F 1s22s22p5 1s22s22p4s1 0,57 0,58

Ne 1s22s22p6 1s22s22p54s1 0,72 0,71

Na 1s22s22p63s1 1s22s22p63d1 0,13 0,13

Molecule Ground stateExcitation

energy(hartree)

Excitation energy(CI)

(hartree)BeH A2Π 0.099 0.092

C2Σ 0.226 0.203

CH Α2Δ 0.097 0.103

D2Π 0.243 0.268


II) Atomistic scale simulationsWe perform electronic

structure calculations andmaterial modeling based on ab-initio methods such as DFT, usingthe open source computationalpackage Quantum Espresso. Atthe moment we are interested inthe absorption of smallmolecules on the [001] surface ofTiO2, because it is relevant to awide range of technologicalapplications such asphotocatalysis. We have studiedthe TiO2 surface doped with Cu inproportions (Ti/Cu=1/1 andTi/Cu=1/4) and we observedboth in rutile and anataseintermediate levels within the

energy gap. Intermediate levels were also observed in the case of anatase which wasdoped with N. Finally, the energy gap seems to be reduced when we dope anatasewith F and O.

b) Anisotropic Photonic Nanocomposite MaterialsWe have generalized the Fortran MULTEM2 program [N. Stefanou, V. Yannopapas

and A. Modinos, Comput. Phys. Commun. 132 (2000) 189-196] for the case that thescatterers are chiral in a nonchiral medium. We presented a detailed analysis of theoptical modes of photonic crystals consisting of submicron chiral spheres in anonchiral isotropic medium, calculated by the full electrodynamic layer-multiple-scattering method. It was shown that resonant modes of the individual spheres,weakly interacting between them, give rise to narrow bands that hybridize with theextended bands of the appropriate symmetry associated with light propagation in anunderlying effective chiral medium. The resulting photonic dispersion diagramsexhibit remarkable features, which are interesting for a variety of applications, suchas the design of polarization-selective filters and novel negative-indexmetamaterials. In particular, we revealed the occurrence of strong band bendingaway from the Bragg points with consequent negative-slope dispersion inside thefirst Brillouin zone as well as sizable frequency gaps, specific to each polarizationmode (Fig. 3). Additionally, we reported a rigorous group-theory analysis to explainqualitative features of the calculated photonic band structure peculiar to a system,which possesses time-inversion but not space-inversion symmetry, and discuss someaspects of the underlying physics to a degree, which goes beyond existinginterpretation. Finally, we proposed and analyzed a layer-by-layer assembly ofmetallic nanorods, with circular cross section, stacked along the z direction. In eachlayer the nanorods are centered at the sites of a square lattice with their axes

Charge Density of

Anatase doped with NCharge Density of

Anatase doped withCu and N


aligned perpendicular to the z direction and mutually twisted through an angle of 60degrees from layer to layer (Fig. 4).

Figure 3: Band diagram and extinction

Figure 4 : Crystal structure of the proposedmaterial

1 2 3 4 5 6 7 8 9 10 11 12 130

1

2

3DO

S

E (eV)

Bulk P lus N N

TiO 2

Anatase

Figure 2: Density of States for TiO2


Active Externally Funded research ProgramsProject “SYNERGASIA”, “Development of Nanocomposite Surfaces for a Safer andCleaner Environment”, February 2011 – February 2013, GSRT

Conference OrganisationAndreas K. Theophilou, Chairman of the Organizing Committee14th International Density Functional Theory ConferenceAugust 29 - September 2, 2011, “DEMOCRITOS NCSR, Athens

Conference Participation1. Theophilou, Iris.

14th International Density Functional Theory ConferenceSpin Projection to Unrestricted Kohn-Sham determinantsAugust 29 - September 2, 2011, Athens

2. Tassi, M14th International Density Functional Theory ConferenceAb initio calculations of excited statesAugust 29 - September 2, 2011, Athens

3. Christofi, A27th Panhellenic Conference of Solid State Physics and Materials ScienceChiral Metamaterials of Metallic Nanorods18-21 September 2011, Cyprus

Invited TalksTheophilou, A. K.Fundamental Principles of Density Functional Theory14th International Density Functional Theory Conference,August 29 - September 2, 2011, Demokritos N.C.S.R., Athens

Teaching and Training Activities1. S. ThanosHeisenberg Hamiltonians, March-May 2011Practical TRAINING, N.C.S.R. Demokritos and Mathematics Department, University ofAthens2. A.K. TheophilouMathematical Methods of Physics, March-July 2011Postgraduate program in physics, School of applied Mathematical and PhysicalScience, National Technical University of Athens


NANOFUNCTIONAL AND NANOCOMPOSITE MATERIALS

Researcher in Charge : C. Trapalis

Researchers : C. TrapalisPost Doctoral Researchers : T. Giannakopoulou, N. Todorova,

E. Vermisoglou, M. Giannouri,V. Georgakilas

External Collaborators : D. Petridis

Ph.D. Candidates: M.V. Sofianou, S. Karapati, T. KalampalikiUndergraduate Students: M. Vassilakou

SCIENTIFIC COLLABORATORS

Prof. C. Lekakou, University of Surrey, U.K. Prof. D. Bahnemann, Institut fur Technische Chemie, Leibniz Universitet

Hannover, Hannover, Germany. Prof. J.G. YU, Wuhan University of Technology, China. Prof. B. Abramović, Faculty of Science, Department of Chemistry, Novi Sad,

Serbia. Prof. I. Dekany, Szeget University, Szeget, Hungary. Prof. K. Pomoni, Physics Dept. University of Patras. Prof. T. Vaimakis, Chemistry Dept, University of Ioannina.

OBJECTIVES

Major objective of the laboratory is the development of nanostructured materialswith targeted functionalities and properties for environment and energyapplications. Laboratory works on the molecular design and surface functionalizationof nanostructured materials. Such materials are sensitive to visible lightphotocatalytic powders and coatings, composite nanoparticles modified with metalsand/or polymers. Graphitic materials like graphite oxide, graphenes, and carbon –metal nanocomposite materials and carbon nanotubes are functionalized in order tobe easy dispersed in organic and/or aqueous solutions. New or modified methodsare applied for nanoparticles synthesis, like sol-gel technology, hydrothermaltreatment, flame and spray pyrolysis techniques etc. Important area of laboratoryresearch is photocatalytic air and water pollutants oxidation aiming to creatematerials for environmental protection, and self-cleaning purposes.


ACTIVITIES AND ACHIEVEMENTS

a) Morphosynthesis of anatase nanocrystals with exposed {001} facets forenvironmental applications

The anatase phase of TiO2 has in most cases higher photocatalytic activity than theother crystalline allotropies. Recently several studies have shown that the (001)surface of anatase is more reactive than the thermodynamically stable (101) surface.This implies that anatase structures with dominant {001} crystal facets will exhibitenhanced photocatalytic properties.

SEM micrograph of TiO2

anatase microcrystalsSEM micrograph ofanatase microspheres

TEM micrograph of the TiO2

anatase nanocrystals

The anatase structures that have been produced with morphosynthesis routes, aremicroplates, nanoplates and hollow microspheres of TiO2 consisted of {001} anatasedominant crystal facets. The formation of dominant {001} crystal facets is managedby combining hydrofluoric acid as a capping agent, which facilitates the formation ofthese crystal facets by lowering their free energy making them more stable and theuse of the hydrothermal-solvothermal method in order to produce highly crystallizedanatase structures. We evaluate the influence of the samples’ morphology on theirphotocatalytic activity for NOx oxidation and acetaldehyde decomposition.

b) Photocatalytic oxidation of NOx under ambient conditions for air purificationover TiO2 /inorganic substrate composites

The activity is focused on the problem of NOx oxidation which is one the mostcommon and harmful air pollutants. The idea lies in the usage of TiO2 photocatalystcomposite materials where the supporting material has a definite affinity to theproducts of the photocatalytic oxidation (NO2, NO3

-). This will increase theeffectiveness of the composite catalyst due to adsorption and storage of theproducts inside the substrate while the catalyst surface will remain unsaturated andopen for photocatalytic process. A set of composites with different wt% ofcommercial P25 Evonik-Degussa and supporting materials like calcium carbonate(PCCB) CaCO3, white cement (PWT), sodium aluminosilicate 14SiO2.Al2O3.Na2O.3H2O(PSAS), talc Mg3Si4O10(OH)2 (PTK), alumina


0 ,0 0 0

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NOx

NONO

2

P M G 30P A L30

P D E 33P TK 33

P S A S 33

P W TC 33

P C C B 33P 25

Phot

onic

effici

ency

(mole

/eins

tein)

Photonicefficiency of theP25/ inorganicsubstratecomposites withapproximately1/3 wt % of TiO2

in thecomposites

Al2O3 (PAL) and magnesium oxide MgO (PMG) were prepared. The photonicefficiencies in oxidation of NO and NO2 as well as in NOx removal for the compositeswith 30-33 wt% of P25 were recorded using a standard technique according toISO/DIS 22197-1. All the composites showed high activity in NO oxidation. Thecomposites with Ba-converted clays exhibited better results in NOx removal from theair phase.

d) Nanomaterials by Flame Spray Pyrolysis

The Flame spray pyrolysis (FSP) is a fast(one step) and versatile process for theproduction of a wide variety ofnanoparticles.

On the right is shown the experimental set-up, constructed in the lab. Mixed metaloxides could be produced and investigatedas photocatalysts. Precursor solution isinjected through the center capillary of theFSP nozzle by a syringe pump at differentrates.

Oxygen is fed through the surroundingannulus as dispersion gas and a supportingCH4/O2 flame surrounding the oxygen gasannulus stabilizes the spray flame.

(c)

0 20 40 60 80 100

(c)

(b)

Inte

nsity

(a.u

.)

2θ (degrees)

(a) WA(%)=60 WR(%)=40

(b) WA(%)=65 WR(%)=35

(c) WA(%)=70 WR(%)=30

(a)

* anataseo rutile

(b)


Finally a sintered metal plate ring providesan additional sheath flow (oxygen ornitrogen) surrounding the spray flame. Toregulate and to monitor all gas flowscalibrated mass flow controllers are used.The particles are collected on a glass fiberfilter with the aid of a vacuum pump.

The relationship between the particleproperties and the synthesis conditions(the combustion environment, that meansexcess or restrictive oxygen, and/or thepump rate of the precursor, and/or theenthalpy combustion of the fuel) is studied.

(a)(a) The Spray Flame Pyrolysis device,(b) Controlled crystalline phaseproduction, (c) Spherical Titaniamicroparticles

e) Few layers graphene for Supercapacitors application

GO is irradiated in a microwave oven (900 W) for ~1min and a fluffy form of carbon,namely Expanded Graphite Oxide, was formed (sample EGO). This material wasactivated by impregnation in aqueous solution KOH, washed, and thermally treatedat 800 oC for 1h. EGO was further decorated with Ag nanoparticles using solar lightirradiation. In the TEM micrographs below the prepared materials are presented.

Bright field TEM image ofEGO (a), thickness map (b)oxygen map (c) of the samegraphene area and HRTEM(d) image showing few layergraphenes.

It was found that microwave expanded GO consists of a few layers approximatelyfour or less. Conclusively, the violent removal of oxygen functional groups thatoccurs during the expansion results in exfoliation of graphite oxide to a large extentand as it was verified by IR spectroscopy to reduction of GO which is furtheraccomplished by thermal treatments. This material has a BET surface area~1316m2/g.

f) Magnetic few layer graphenes via pillaring of graphite oxide for Supercapacitors

Graphite oxide was pillared with [Fe3O(CO2C6H4NH2)6(H2O)3]+ a complex trinuclearcompound of iron (III) with p-aminobenzoic acid, where the amino groups react withthe epoxy groups and thus is grafted to the graphite oxide layers. The reaction is


leading to enhanced interlayer distance of graphene oxide layers. This was verifiedby the XRD patterns where natural graphite exhibits a peak at 26.54o with a basalspacing d002 =3.34 Å while in the case of GO a 001 peak appears at 12.02o with abasal spacing of d001=7.35 Å. Pillaring with the iron – aminoacid complex results inthe increase of d001 spacing (12.1Å) which corresponds to an interlayer separation of12.1-6.1=6.0Å where 6.1Å is the thickness of graphene oxide layers. When pillaredgraphite oxide was thermally annealed at 800 oC in vacuum for 2 hours the XRDpattern illustrated the existence of iron carbide and a low intensity broad peak at~26o indicating a hybrid iron carbide-graphene nanostructure. This approach mayopen new perspectives for relatively lightweight magnetic graphene materials,appropriate for a variety of applications.

g) Clay mediated graphene sheets

The smectite clay used in this work was a natural dioctahedral montmorillonite,obtained from Kunimine Industries Co. (Japan), Kunipia F (KUN), with structuralformula Ca0.11Na0.891(Si7.63Al0.37)(Al3.053Mg0.65Fe0.245Ti0.015)O20(OH)4 and cation-exchange capacity (CEC) 1.18 meq g-1 of clay. Dimethyldioctadecylammonium(DODA) chloride purity of 99+% (Sigma-Aldrich) was used as surfactant. Modificationof hydrophilic Kunipia F based on cation exchange of sodium ion with the surfactant:Me2N-(C18H37)2Cl results in an organophilic clay appropriate for the dispersion ofexfoliated graphite. Exfoliated graphite was derived by microwave irradiation (900Wfor 1 min) of expandable graphite provided by Asbury Carbons. These hybrid solidshold the promise of important applications, such as catalysts and catalyst supports,gas sorption/separation, waste absorbents, liquid decolorizers, and anode materialsin lithium batteries. Furthermore, the clay properties offer the possibility to load theclay surfaces with various metal ions or metal oxide catalysts that can add furthertechnological value to the composites.

0.001 mg of exfoliated graphite(left) and 60 mg of organoclay(middle) in 7 ml xylene aftersonication for 1h resulted in asuspension stable for over 1month (right).

h) Functionalisation of graphene and composite formation.

Graphite can be dispersed in graphene nanosheets (single monolayers or few layersgraphene) by an extended sonication in dimethylformamide. The dispersedgraphene sheets are then functionalized by 1,3 dipolar cycloaddition by azomethineylide affording organically modified graphene sheets. The experimental data showedthat the time of this reaction is the most important factor to control the extent of


the functionalisation and thus the properties of the modified graphene. In the nextimage, the Raman spectra of the starting graphene and the functionalized grapheneafter 5 hours and 5 days reaction are presented. The organically modified graphenederivatives are easily and finely dispersible in several polymers such as PMMA,polyvinyl acetate etc.

Raman spectra of thestarting graphene andfunctionalizedgraphene after 5 hoursand 5 days reactiontime.

Our group also studies the formation and the properties of nanocomposite materialsthat formed by the mixing of organically modified Carbon nanotubes and graphenenanosheets. Such nanocomposites that combine the one dimension carbonnanotubes with the two dimensional graphene are expected to have interestingproperties as regards electric conductivity or mechanical reinforcement of polymers.

Teaching and TrainingC. Trapalis1. Member of the advisory committee of Ph.D. candidate M.B. Sofianou, Univeristyof Ioanina, 2009-2012.2) Lecturer on Physical Chemistry, Open University of Greece, 2010-20112) Lecturer in Materials Technology, ΑΤΕΙ-Athens, 2010-11.


1. Sofianou, M.V., Trapalis, C., Boukos, N., Vaimakis, T., Yu, Jiaguo, Wang,WenguangEuropean Symposium on Photocatalysis, JEPStudy of TiO2 Anatase Nano and Microstructures with Dominant {001} Facetsfor NO OxidationBordeaux, 29-30 September, 2011, France.

2. Sofianou, M.V., Vaimakis, T., Trapalis, C.Anatase TiO2 Nanostructures with Exposed {001} Facets for Air PollutantsOxidation8th International Conference on Nanosciences & Nanotechnologies (NN11)Thessaloniki, 12-15 July, 2011, Greece.

3. Todorova, N, Vaimakis, T., Giannakopoulou, T., Hishita, S., Trapalis, C.Vissible Light Active TiO2 Nanostructured Photocatalysts8th International Conference on Nanosciences & Nanotechnologies (NN11)Thessaloniki, 12-15 July, 2011, Greece.


RESEARCH PROGRAMS - FUNDING

1. “Development of High Energy Power Density Supercapacitors for AutomotiveApplications”, AUTOSUPERCAP, 2011-13, EU, 308.000€, Partner.2. “Development of Nanofunctional Materials for Safe and Clean Environment”,ARISTON, 2011-14, 305.000€, GSRT, Coordinator.3. “Photocatalytic NOx Oxidation Under Ambient Conditions for Air Purification”,Bilateral Collaboration Program Greece – Turkey, 2011-12, 15.000€, GSRT,Coordinator.4. “Nanostructured Materials for Air Purification”, Bilateral Collaboration ProgramGreece - Germany, IKYDA, 2009-11, 15.000€, IKY, Coordinator.


BIOINORGANIC CATALYST CENTERS AND MIXED VALENCE MULTINUCLEARCOMPLEXES

Research Director: Vassilios PetrouleasPermanent Research Staff: Yiannis Sanakis, Nikolaos IoannidisPhD Candidates: Theodora Tzima, Maria Chryssina

External Collaborators:Prof. P. Kyritsis, Dept of Chem. Univ. of AthensProf P. Paraskevopoulou, Dept of Chem. Univ. of Athens, GreeceProf. V. Melissas, Dept of Chem. Univ. of Ioannina, GreeceProf. P. Akrivos, Dept of Chem, Aristotle Univ. Thessaloniki, GreeceProf. V. Tangoulis, Dept of Chem, Aristotle Univ. Thessaloniki, GreeceProf. R. G. Raptis, Dept. of Chemistry, Univ. of Puerto Rico, Puerto RicoProf. G. Christou, Dept of Chemistry, Univ. of Florida, U.S.A.Prof. A. Tasiopoulos, Dept of Chemistry, Univ. of Cyprus, CyprusProf. D. Ghanotakis, Dept of Chemistry, Univ. of Crete, GreeceProf. K. Kotzabasis, Dept. of Biology, Univ. of Crete, Greece

Areas of Research:The project aims toward (a) the understanding and synthetic simulation of thefunction of active centers in biological systems, which catalyze important processes(conversion of light energy to electric charge separation, water oxidation,electron/proton transfer etc), and (b) the study of the electronic and magneticproperties of syntheticmultinuclearcomplexes of transitionmetals.Emphasis is given in tothe study of thetetranuclear Mncomplex, whichoxidizes water andconstitutes part of theso called PhotosystemII. In contemporaryterminologyPhotosystem II couldbe characterized as amodel multi-functionalnanostructured system,whereas the Mn4complex exhibits interesting analogies with the molecular magnets. Many syntheticmultinuclear complexes of transition metals exhibit interesting properties, whichrender them candidates for technological applications in the field of magnetic data

3200 3300 3400 35003200 3300 3400 3500

b

untreated

Magnetic field (Gauss)

120 G

Magnetic field (Gauss)

170 G

c

a

127 K

c

ba

170 G

150 K

glycerol 50%

124G

Figure 3

Figure 1. Isolation of the wide component of the S2YZ• spectrum,

trace a, from the signal trapped at the indicated temperatures,trace b, by subtraction from the latter of a fraction of thenarrow signal induced at 10 K, trace c


storage, magnetic cooling, quantum computing, or in their use as magneticresonance contrast agents.

Activities and Achievements:A) EPR studies on short-lived reaction intermediates trapped during the S-statecycle of Photosystem II. The oxygen evolving complex, OEC, of Photosystem II, PSII,undergoes, during its catalytic cycle, four one-electron oxidation transitions, S0 –S1,..., S3 – (S4)S0 driven by the photo-oxidation ofthe chlorophyll species P680. Oxygen evolvesduring the S3 to (S4)S0 transition, the S4 being atransient state. There are two major steps oneach S-state transition; the oxidation of anappropriately positioned tyrosine, YZ, by P680

+

and the subsequent oxidation of the centralcatalytic core, the Mn4CaO5 cluster, by oxidizedYZ. Proton translocation is a dominant factor,being the rate limiting step for the partialreactions leading to oxygen evolution. In the firstplace, the redox function of YZ is coupled toproton exchange with a nearby base,presumably H190. In the second, one electronand on the average one proton are extractedfrom the Mn cluster on each S-state transition.No net proton release is observed in the S1 to S2

transition and the Mn environment is consideredto be more electro-positive in S2 and S3. We haveextended our earlier studies on the S2YZ

•

intermediate that is trapped by illumination inthe temperature range 77 K to 190 K of samplespoised in the S2...QA state. X-band EPRexperiments at 10 K indicate that theintermediate consists of two components. Awide one with a splitting of ca. 170 G, and anarrow one characterized by a splitting of ca.120 G (untreated), or 124 G (glycerol treated samples) (figure 1). Lowertemperatures of illumination in the above temperature range favour the widecomponent, which at 10 K decays faster than the narrow one. Re-illumination at 10 Kafter decay of the signal trapped at 77 – 190 K induces only the narrow component.Rapid scan experiments in the temperature range 77 – 190 K reveal high resolutionspectra of the isolated YZ

• radical and no evidence of alternative radicals. The twosplit signals are accordingly assigned to different conformations of the S2YZ

•

intermediate. A point-dipole simulation of the spectra yields "effective distances"between the spin densities of YZ

• and the Mn4Ca center of 5.7 Å for the wide and6.4Å for the narrow component (figure 2). The results are interpreted with respect to amolecular model assuming two sequential proton transfers during oxidation of YZ.

3200 3300 3400 3500

o

124 G

170 G

r = 5.70 (0.04) A

r = 6.40 (0.05) A

Figure 6

o

Magnetic Field (Gauss)Figure 2. Theoretical simulation ofthe X-band-EPR S2YZ• split signalsof glycerol treated samples.Continuous traces are theexperimental spectra a and c of theright panel of Figure 1. Dashedtraces are simulations on the basisof the point dipolar model with S1 =S2 = 1/2, g1 = g2 = 2.003 and r =6.40 Å, r =0.05 Å and r = 5.70 Å, r=0.04 Å, as indicated. A residuallinewidth of 5 G was used.


The wide component is assigned to a transient S2YZ• conformation, which forms

during the primary proton transfer (scheme 1).

T=4.2 K

+e--e-

T>77 K

T=4.2 K

Tyr 161

His 190

Asn 298

-e- +e-

wide signal narrow signal

S2

Tyr 161

His 190

Asn 298

T>77 K T=4.2 K

-t ~ hours

4.2 K

S2YZ

Tyr 161

His 190

Asn 298

S2YZTyr 161

His 190

Asn 298

S2t

T=4.2 K

+e--e-

T>77 K

T=4.2 K

Tyr 161

His 190

Asn 298

-e- +e-

wide signal narrow signal

S2

Tyr 161

His 190

Asn 298

T>77 K T=4.2 K

-t ~ hours

4.2 K

S2YZ

Tyr 161

His 190

Asn 298

S2YZTyr 161

His 190

Asn 298

S2t

Scheme 1. Schematic illustration of the suggested deprotonation events during tyrosineoxidation in the S2 state.


B) Polynuclear Transition Metal Clusters(I) Magnetic Interactions Between Antiferromagnetic Trinuclear Cu(II) clusters.Exchange coupled trinuclear clusters comprising half ineteger spin transition metalions constitute an intense field of our research. In the past we explored the magneticproperties of isolated trinuclear clusters including a variety of metal ions

(Fe(III)(S=5/2),Cr(III)(S=3/2) andCu(II)(S=1/2)) and wewere able todetermine criticalfeatures in theirmagnetic propertiessuch as thecontribution of

antisymmetricexchange. Interestingmagnetic relaxationpropeties wererevealed in the caseof a ferromagneticCu3 and anantiferromagnetic Fe3

cluster. In all thesecases the propertieswere derived fromisolated clusters. Infigure 3 we show thecrystal structure of

complex[Et3NH][Cu3(µ3-OH)(µ-pz)3(PhCOO)3]·H2O (1). Compound 1 (figure 3) can be viewedas a dimer of trimers connected by two H-bonds in the solid state. Magneticmeasurements indicate strong intra-trimer antiferromagnetic coupling yielding (pertrimer) an S = 1/2 ground state. Moreover, the data indicate the significantcontribution of antisymmetric exchange and negligible (if any) inter-trimer exchangeinteractions. Dual mode EPR spectra recorded at liquid helium temperatures (figure4) indicate that the two trimers interact through point dipolar interactions with aneffective distance of 4.5 Å in reasonable agreement with the crystal structure. Infrozen solutions the EPR spectra at liquid helium temperatures are consistent withisolated S=1/2 trimers indicating that in solution the H-bonds break. Moreover, theS=1/2 signals exhibit axial anisotropy with g<2.0 attributed to the effects ofantisymmetric exchange in agreement with the magnetic susceptibility data.

(II) Polynuclear Transition Metal Clusters as Building Blocks for 3D netwowrks.Over the last years, polynuclear metal complexes have emerged as building blocksfor the construction of polymeric complexes known as Metal-Organic Frameworks(MOFs). The [Fe8] pre-isolated clusters of the type [Fe8(μ4-O)4(4-R-pz)12X4] (Figure 5)were utilized for the construction of such materials. By appropriate replacement of

150 300 450 600

_|_

B (mT)

||

Figure 4. Dual mode X-bandEPR spectra from a solidsample of 1. The strongsignal in parallel mode at 170mT is a “forbidden transition”from a system comprisingtwo anisotropic S = 1/2 spinswith g<2.0 exhibiting dipolarinteractions.

Figure 3. Arrangement ofthe two Cu(II) trimers incomplex 1. Copper ions areshown as blue balls


the terminal ligand X- efforts are undertaken in orded to construct 3D networksfetauring the [Fe8]-O-[Fe8] motif. The 3D network is expected to adopt a diamondtopology. Mössbauer spectroscopy in combination with magnetic susceptibilitymeasurements was used to characterize these materials. Represenative zero fieldMössbauer spectra recorded at various temperatures are shown in figure 6. Above35 K the spectra comprise quadruple doublets attributed to different ferric sites ofthe [Fe8] units. Below 30 K the spectra split to magnetic sextets. The combination ofmagnetic susceptibility measurements and Mössbauer spectroscopy indicate thatthese materials exhibit as spin glass behavior.

Conference ParticipationSanakis, Y.EUROMAR 2011Spin Relaxation in trinuclear clusters comprising half integer spin ions21-25 August 2011, Frankfurt am Main, Germany

Invited TalksIoannidis N.4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsMetalloradical EPR Signals in Photosystem IIJune 14-18, 2011, Patras, Greece

Figure 5. Crystal structure of the [Fe8] clusters usedto build 3D materials. The ferric ions are shown asorange balls.

-10 -8 -6 -4 -2 0 2 4 6 8 10

40 K

35 K

30 K

25 K

20 K

15 K

10.3 K

4.2 K

v (mm/s)

Figure 6. Temperature dependency of zero fieldMössbauer spectra from a sample comprising [Fe8]-O-[Fe8] units in a 3D network.


Tzima Th.4th North America-Greece-Cyprus Workshop on Paramagnetic MaterialsDFT Evaluation of the Spectroscopic Properties of Iron and Manganese compoundsJune 14-18, 2011, Patras, Greece

Sanakis, Y.Dept. of Chemistry, University of AthensEPR and Mossbauer Spectroscopy in the Study polynuclear transition metal andlanthanide clusters. From Photosynthesis to Quantum ComputingJune 2, 2011.

Teaching and Training ActivitiesYiannis SanakisExternal examiner in two PhD theses (Dept of Chemistry, University of Athens)Yiannis SanakisGraduate course “Molecular Magnetism”, University of Ioannina (6 hours)

Masters Degree projects completed in 2011.Maria ChryssinaChanges of the water-splitting complex during the S2 to S3 transition. An EPRSpectroscopic Study.Research Supervisor at NCSR “D”: V. PetrouleasDept of Chemistry, University of Athens.


ELECTRON MICROSCOPY AND NANOMATERIALS

MOLECULAR BEAM EPITAXY AND SURFACE SCIENCE

SOL GEL / PULSED EPR LABORATORY

ADVANCED CERAMICS LABORATORY

RESEARCHERS

P. Aloupogiannis, N. Boukos, A. Dimoulas, G. Kordas, G. Mitrikas, A. Travlos, G.Vekinis

RESEARCHER OFFICERS

G. Xanthopoulou


P. Bilalis, A. Chroneos, E. Efthimiadou, I. Kartsonakis, N. Kelaidis, A. Karatzas, L-E.Tziveleka, E. Xenogiannopoulou

PhD STUDENTS

A. Angelopoulou, A. Balaskas, E A. Chatzipavlidis,. Golias, A. Marinou C. Tapeinos,G. Giannopoulos, E. Manios, T. Tzima, M. Chryssina, D. Koumoulis, N. Panopoulos, D.Tsitrouli, I. Theophilou, M. Tassi, A. Christofi, M.V. Sofianou, S. Karapati, T.Kalampaliki, G. Margaris, A.N. Georgopoulou, G. Varelas

PROJECTS

PROGRAM IIELECTRONIC AND COMPOSITEMATERIALS

PERSONNEL


ELECTRON MICROSCOPY AND NANOMATERIALS

Research Director: Anastasios TravlosPermanent Research Staff: Nikolaos BoukosContract Researchers: Chryssoula ChandrinouMasters Students: Sigiava Aminalragia GiaminiExternal Collaborators:Prof. R. Vladea Petroleum Institute, Abu Dhabi, United Arab EmiratesDr. A. Kean, Mantis Deposition Ltd, Thame, UKAssoc. Prof I. Zergioti, NTUA, Athens GreeceProf. P. Lianos, U. of Patras, GReeceProf. X.E. Verikios, U. of Patras, GReece

Areas of Research:Semiconducting oxides nanostructures

Activities and Achievements:ZnO based nanostructuresZnO is a wide band gap (3.3 eV) semiconductor, which has been the subject ofintense interest in recent years. The attractive features of ZnO for optoelectronicapplications, in addition to its wide band gap – similar to that of GaN – are its highexciton binding energy (60 meV) and the availability of bulk ZnO single crystals.Additional advantages of ZnO are that it can be easily processed by wet chemicaletching and that it has excellent stability under high-energy radiation. Furthermore,it can be grown in a variety of nanostructured morphologies, and by low cost, lowtemperature methods. Still a major problem for the fabrication of optoelectronicdevices is efficient p-type doping of ZnO. Even though a lot of research effort hasbeen devoted to p-type doping, there is no generally accepted methodology for theproduction of stable and reproducible p-type ZnO. Furthermore there isdisagreement regarding the origin of the above problem. Some researchers haveattributed it to unintentional impurity doping such as H forming shallow donorstates, while others to self-compensation by intrinsic point defects. The intrinsicpoint defects are considered to play a profound role in the electrical behavior ofZnO. Zinc interstitial, Zni, is generally considered to act as a donor. However, itsposition in the energy gap of ZnO and its optical signature are debatable.During the past year we focused in the study the optical signatures of Zn vacanciesand interstitials utilizing low temperature photoluminescence(PL) measurements in ZnO nanorods, contributing to the understanding of the defectphysics of ZnO which is quite complex and to a large extent unknown. Since themethod of creating and annihilating VZn and Zni is the controlled in and out-diffusionof Zn atoms from the surface of ZnO, the form of thin nanorods has been chosen, asopposed to bulk single crystal or polycrystalline thin film, in order to minimize therequired diffusion lengths while maintaining single-crystalline samples.


Fig. 1. (a) SEM inclined view of as-grown ZnO nanorods. (b) Typical TEM bright fieldimage and corresponding SAED pattern shown in the inset of an as-grown ZnOnanorod.

Fig. 2. PL spectra, obtained at T=4.2 K, of ZnO nanorods that underwent varioussuccessive treatments: (1) annealing in air at 550 °C for 30 min, (2) deposition of Znin vacuum and in situ annealing at 150 °C for 10 min, (3) annealing in air at 150 °C for20 min and (4) annealing in air at 550 °C for 60 min. The spectra are shifted on thevertical axis for clarity.

The temperature PL measurements revealed that they resulted in a consistentvariation of Zni and VZn population. The Zni are related to the 3.405 eV Dh peakverifying that Zni is a shallow donor lying 30 meV below the conduction bandminimum in agreement with electrical measurements and theoretical calculations.The VZn are related to the 3.308 eV eA peak and have an activation energy of 123


meV in agreement with previous results. The DBX associated with Zni was found tobe at 3.364 eV with a localization energy of9 meV, while the ABX associated with VZn at 3.359 eV with a localization energy of 13meV. Finally a DAP corresponding to a transition from Zn i donors to VZn acceptorswas found at 3.331 eV. The identification of these intrinsic defects is expected tofacilitate the efforts for p-type doping of ZnO.

TEM study of nanomaterialsA wide range of nanomaterials were studied by TEM techniques including HRTEM,EELS and EFTEM in order to optimize their growth conditions and tailor theirproperties, including nanomaterials for photovoltaics, catalysis, drug delivery,biomedical and energy applications.

TEM study of ncTiO2/QD CdS solid state hybrid solar cell


TEM study of poyindole-NiO composite polymer electrolyte for Li batteries

Selected Publications in International Refereed Journals

1. Thangadurai, P., Zergioti, I., Saranu, S., Chandrinou, C., Yang, Z., Tsoukalas, D.,Kean, A., Boukos, N.ZnO nanoparticles produced by novel reactive physical deposition processApplied Surface Science, 257 (12), pp. 5366-5369, (2011).

2. Alexiadis, V.I., Boukos, N., Verykios, X.E.Influence of the composition of Fe 2O 3/Al 2O 3 catalysts on the rate ofproduction and quality of carbon nanotubesMaterials Chemistry and Physics, 128 (1-2), pp. 96-108 (2011).

3. Papavasiliou, A., Tsetsekou, A., Matsouka, V., Konsolakis, M., Yentekakis, I.V.,Boukos, N.Synergistic structural and surface promotion of monometallic (Pt) TWCs:Effectiveness and thermal aging toleranceApplied Catalysis B: Environmental, 106 (1-2), pp. 228-241 (2011).


4. Chatzipavlidis, A., Bilalis, P., Efthimiadou, E.K., Boukos, N., Kordas, G.C.Sacrificial template-directed fabrication of superparamagnetic polymermicrocontainers for pH-activated controlled release of DaunorubicinLangmuir, 27 (13), pp. 8478-8485, (2011).

Total number of publications in international refereed journals: 11

Active Externally Funded research ProgramsMarie Curie-IAPP, FP7, "NANOSOURCE", 2008-2012, 112.000 Euro

Teaching and Training ActivitiesAnastasios TravlosTraining on asbestos materials and related works. 8-11/03/2011 (12 hours)ELINYAE, Athens, Greece

Anastasios TravlosTraining of medical doctors on Professional Health. June 2011 (5 hours)National School of Public Health, Athens, Greece

Nikolaos BoukosNanomaterials labMSc course "Microsystems and Nanodevices", NTUA, Athens, Greece

Nikolaos BoukosExperimental Methods labMSc course "Technological Applications of Physics", NTUA, Athens, Greece

Nikolaos BoukosMaterials Characterization Methods labUndergraduate course, School of Applied Mathematical and Physical Sciences, NTUA,Athens, Greece


MOLECULAR BEAM EPITAXY AND SURFACE SCIENCE

Research Director: A. Dimoulas

Post-doctoral Researcher: D. Tsoutsou

Contract Researchers: A. Chroneos, E. Xenogiannopoulou, N. Kelaidis

PhD Candidates: E. Golias

External Collaborators: L. Tsetseris (NTUA), V. Ioannou-Sougleridis (IMEL-NCSRD), E. Evangelou (U. Ioannina), S.T. Pantelides (Vanderbilt U.), M. Barozzi &coworkers (U. Trento), F. D’ Acapito (ESRF), F. Boscherini (U. Bolonia), M. Fanciulli& coworkers (CNR-IMM/MDM), G. Le Lay & co-workers (CNRS/U. Aix Marseilles),M. Heyns & coworkers (Imec)

Areas of Research:New electronic materials and devices delivering high performance, increasedfunctionality and low power operation to satisfy technology requirements andsocietal needs beyond year 2020.

Activities and Achievements:For more than a decade, the MBE and Surface Science Laboratory worked in the areaof high-k gate dielectrics and high mobility channels for advanced CMOS. The lab hasled a series of flagship EU projects, the last being DUALLOGIC, which has successfullyended in June 2011 (for a brief summary of results visit herehttp://cordis.europa.eu/fetch?CALLER=OFFR_O_BUSI_EN&ACTION=D&DOC=1&CAT=OFFR&QUERY=0133445b55f7:c7fd:232a4d69&RCN=7176).

As we are approaching the end of the CMOS roadmap, researchers worldwideprepare for the future generations of nanoelectronics beyond year 2020. The maingoal in 2011 was to realign our research with the new requirements and re-defineour research policy and long term goals to make the transition from advanced CMOSto future post CMOS materials and devices. This effort was very successful since thelaboratory managed to secure significant funding from EU and Greek researchprograms for the next 4 to 5 years which sum up to approximately 2 MEURO. Basedon this funding the lab will expand with new PhD students, postdoctoral researchersand new growth and characterization equipment.

The main research direction is toward 2D -ultimately thin- dissipationless channelsand complex smart gates combining high performance and ultra low poweroperation. Atom thick channels such as silicene and germanene (the sp2-hybridized Siand Ge equivalent to graphene) combined with graphite like hexagonal dielectricssuch as BN and AlN will be at the center of focus of 2D-NANOLATTICES project(http://www.2dnanolattices.eu) coordinated by the MBE lab.


In addition, in the new project SMARTGATE (http://www.smartgate-erc.eu) fundedby a prestigious ERC (IDEAS) grant, the principle investigator Dr. Dimoulas and histeam will study negative capacitance FETs comprising complex graphene andtopological insulators-based gates. The aim is to demonstrate steep slope switcheswith subthreshold slope S below the Boltzmann thermal limit of 60 mV/decade toreduce the operating voltage down to 0.1 V, an order of magnitude smaller than inpresent day devices. SMARTGATE is the first and only ERC grant in Greece awardedin Electrical and Communications Engineering/Micro and Nanoelectronics andsignifies the leadership of the MBE team of NCSR DEMOKRITOS in GreekNanoelectronics. The effort in SMARTGATE will be complemented by a grant fromthe Greek ERC (ARISTEIA) program through the project TOP-ELECTRONICS retainedfor funding. In addition, the MBE team has become part of the 10-year FET Flagshipinitiative Guardian Angels which provides an excellent platform for theimplementation of our plans in line with the roadmap for low power/ energyefficient nanoelectronics.

In the framework of 2D NANOLATTICES, we study allotropic forms of Si and Ge likesilicene and germanene, which do not exist in Nature but they could be engineeredon suitable “friendly” substrates. In the first 6 months from the project start, wehave already obtained the first encouraging results:

4 x 4


Fig. 1 Si/Ag (111) : Left, RHEED patterns; Right, stable 4x4 trigonal superstructure formed by Silicenehoneycomb lattice on Ag (111) surface. Highlighted, dark blue Si atoms above Ag are higher,indicating buckling of silicene layer.

We found that, remarkably, Si and Ge wet the surface of Ag (111) instead of forming3D clusters. Moreover, Si and Ge atoms arrange themselves in an ordered manneron top of the Ag surface as seen by RHEED (Fig.1 and 2).

Fig. 2 Ge/Ag (111): The x3 pattern in the right figure is indicative of a (√3 x√3) R 30o superstructure

The RHEED pattern for Si (Fig. 1, left) indicates a 4x4 trigonal superstructure whichcould be formed by laying a silicene honeycomb lattice on top of Ag (111) as shownin Fig. 1(right). This superstructure has recently been confirmed by our CNRScollaborators in a PRL publication (P. Voigt et al., Phys. Rev. Lett. 108, p155501,2012) while jointly with our NTUA collaborators we have predicted by DFTsimulations that the superstructure of Fig. 1 (right) is energetically stable, albeit withan appreciable buckling indicating a mixed sp2/sp3 hybridization. Theaforementioned results are first concrete evidence that buckled silicene on Ag ispossible. Further research is underway to determine the influence of this buckling onthe electronic band structure and verify whether 4x4 sillicene on Ag has propertiessimilar to graphene.

In the case of Ge on Ag, the most striking result is a (√3 x√3) R 30o superstructure(see RHEED pattern in Fig. 2) which appears at low coverage of about 1/3 anddisappears at higher coverage above 1. This Ge-related superstructure drasticallymodifies the valence band structure of Ag (111) along -M direction of the surfaceBZ as shown in Fig. 3, however, the real space atomic configuration remainsunresolved at present.


Fig. 3 Valence band structure of bare Ag (111) and Ge/Ag (111) surfaces determined by angle resolvedUPS

Active Externally Funded research ProgramsHere only the projects started in 2011 are given. Projects ERC/SMARTGATE and ARISTEIA/TOP-ELECTRONICS have already been approved in 2011 but they will be described in nextyear’s Annual Review

FP7-PEOPLE-2010-IEF “REACT”-273631 “Rare Earth Oxide Dielectrics for AdvancedGermanium CMOS Technology” See CORDIS website for detailshttp://cordis.europa.eu/fetch?CALLER=FP7_PROJ_EN&ACTION=D&DOC=2&CAT=PROJ&QUERY=0133888de35a:ff8d:236210bf&RCN=98203Started: May 1, 2011: Total duration: 24 months,Total budget: 157 720 Euro.

FP7-ICT -2009-C (FET Open) “2D-NANOLATTICES” -270749 (STREP) “Strongly anisotropicgraphite-like semiconductor/dielectric 2D nanolattices” See CORDIS website for details:http://cordis.europa.eu/fetch?CALLER=PROJ_ICT&ACTION=D&DOC=1&CAT=PROJ&QUERY=01334ef468c4:3bc9:268fcfb3&RCN=99649.Started: June 1 2011, End date: May 31 2014 (3 years).Budget for NCSRD: 407 038 Euro.


Conference ParticipationE. Golias.Title of Talk: Ge-related impurities in high-k oxides: carrier traps and interaction withnative defectsConference Title: INFOS 2011Conference dates, location MINATEC, Grenoble, June 25

Invited TalksA. Dimoulas.Title of Talk: High mobility channels for advanced CMOSConference Title: INFOS 2011 tutorialConference dates, location MINATEC, Grenoble, June 25

Degree Diploma projects completed in 2011.Name Ikaros HaugeTitle “Αδρανοποίηση Φορέων Επιφάνειας Αρσενικούχου Γαλλίου (GaAs) απόΑλουμίνιο (Al) και Σελήνιο (Se)" (“Passivation of GaAs surface by Al and Se”)Research Supervisor at NCSR “D”: A. DimoulasDiploma Thesis submitted at: NTUA .


SOL-GEL / PULSED EPR Laboratory

Research Director: G. Kordas

Permanent Research Staff: G. Mitrikas

Contract Researchers: I. Kartsonakis, P. Bilalis. E. Efthimiadou,A. Karatzas, L-E. TzivelekaB.

PhD Candidates: A. Angelopoulou, A. Balaskas,C. Tapeinos, A. Chatzipavlidis

Masters Students: K. Metaxa, G. Pappas, P. Kenourgios

External Collaborators: X. Ribas, C.Charitidis, A.Stalios, T.Hack,M.Zheludkevich, C.Simon, D.Shchukin, G.Grundmeier, S.Schroeder, J.Norwig, J-A.Vogelsang, P.Warszynski, A.Jovanovic, F.Montemor, D.Bassan, S.Dietrichson,L.Maitan, C.Witt T.Schmidt-Hansberg, H-J.Tenhu, K.Dolinski

Areas of Research:Development of technology for corrosion protection of various metal alloys used incar and airplane industries. Studies of protection layers based on conductivepolymers, nanocontainer technology, and sol-gel methods. Implementation ofpulsed EPR methods and development of new materials based on electron andnuclear spins for quantum computation including molecule based magnets andmolecular spins like encaged atomic hydrogen in silicon-oxide matrices.Development of nanocontainers exhibiting triple stimuli response for targeted drugdelivery towards the treatment of prostate and breast cancer.

Activities and Achievements:a) Self-healing hybrid organic-inorganic coatings including “smart” nanocontainersfor corrosion protection of metal alloys. A new system has been developed for thecorrosion protection of various metal alloys in the framework of FP7 project ‘MUST –Multi-level protection of materials for vehicles by ‘smart’ nanocontainers’. The metalalloys are hot dip galvanized (HDG) steel, aluminium alloy (AA) 2024-T3, magnesiumalloy ZK10 and ZK30. This system includes hybrid organic-inorganic coatings togetherwith ceramic nanocontainers loaded with corrosion inhibitors. The nanocontainersare based on cerium molybdate and titanium oxide compound. The basic corrosioninhibitors that are used are 2-mercaptobenzothiazole, 8-hydroxyquinoline andcerium nitrate


Fig. 2. The multiple responses of syntheticnanoconatainers.

due to their unique inhibitproperties on the aforementionedmetal alloys. The corrosionresistance of the coatings wasexamined using EIS. The resultsrevealed improved corrosionprotection after immersion in 0.5M NaCl solution for 12 months.The addition of nanocontainersloaded with corrosion inhibitorimproved the anticorrosiveproperties of the coatings compareto the coatings that have emptynanocontainers or the coatingsthat have only the inhibitor. The concentration of the loaded nanocontainers intothe coating is an important factor for further improvement of the anticorrosiveproperties of the coating. In order possible self-healing properties of the coatings tobe estimated, artificial defects formatted on the coatings. The coatings including 4-10% w/w loaded nanocontainers presented partial recovery action of the defectedarea after immersion in 5 mM NaCl solution. These results disclose self-healingproperties of the coatings. Fig. 1 depicts the schematic self-healing mechanism of adefected from corrosion agents of a coating including nanocontainers. It is observedthat after the scratched generation, the inhibitor (green color) has been releasedfrom the nanocontainers and has covered the exposed metal area of the substrate.

b) Novel nanocontainer drugcarriers for targeted treatmentof prostate cancer. In theIDEAS project we have alreadydeveloped a novel technologyfor nanocontainers fabricationeither via distillationprecipitation polymerizationmethod or via synthesis byseed emulsion polymerization.Briefly, we fabricate a varietyof nanoparticles with differentcombinations in their responsesuch as pH, Thermo, Magneticand Redox sensitivity (Fig. 2). Itis crucial for our study to be

referred that we have already synthesize a quarto sensitive nanocontainer (pH,Thermo, Redox and Magnetic). After the nanocontainers’ fabrication, their surfacewas modified aiming at providing to our nanocontainers better solubility (Peg), lowphagocytaric reaction (Peg) and improving their targeting in specific sites of cancercells (Folic acid modification and specific ligands) and finally we create fluorophoreprobes (FITC or QD, Fig. 5). Finally we also coated their surface with polylactic acidand polysaccharides which are both biodegradable polymers.

Fig. 1. Schematic representation of self-healing mechanism


We evaluate the encapsulation efficiency (EE %), the loading capacity (LC %) and tostudy the release properties under different conditions. For this purpose we useanthracyclines as model drugs. We have already developed a hyperthermia apertureaiming at investigating the release of the drug in these conditions. Small animalpreliminary tests are on progress.

Our objective is to engineer a new nanoscopic device that combines stability, highdrug loading along with pH and redox response. (Fig. 3b).

Another synthetic example whichdeals with the synthesis andcharacterization of hollowmicrospheres via seed emulsionpolymerization is presented in Fig.4. MTT and Trypan Blue assayswere used to study thenanocontainers cytotoxicity in thebreast cancer cell line, MCF7. Cellsrelatively retained their viability in thepresence of the microspheres alone,the DNR-loaded microspheres exhibited enhanced cytotoxicity compared to the freedrug. Fig. 5, represents the confocal images of the synthesized nanocontainers afterDox & Fitc functionalization.c) Pulsed EPR characterization of encapsulated atomic hydrogen in POSS cages.Paramagnetic atoms encaged in molecular cages are promising components of spin-based quantum computing because they can be precisely placed into large arrays bychemical engineering. Trapped atomic hydrogen is even more attractive due to itssimpler electronic 1s state and the exceptionally large hyperfine coupling of1420.406 MHz. Polyhedral octa-silsesquioxanes (POSS) are ideal cages for this purpose.The aim of this project is to evaluate key

Fig. 3. (a) TEM image of magneticnanocontainers, (b) pH responsiveness ofsynthetic nanoparticles

Fig. 4. TEM images of hollow nanocontainerswith and without MNPs

Fig. 5. (a) DOX conjugated, (b) FITC conjugationon nanocontainers’ surface


Fig. 6. (a) Encapsulated H in POSS cage. (b) Temperature dependence of TM. (c) 29Si HYSCORE spectrumshowing the hyperfine interaction between the 1s electron and the Si nuclei of the cage.

properties for quantum computing like the spin-lattice T1 and spin-spin TM relaxationtimes and to address the question if these species can rival endohedral fullerenes asqubit embodiments. The detailed pulsed EPR study showed that: 1. The room-temperature phase memory time TM=13.9 μs for the system with R=OSi(CH3)2H is thelongest observed so far for this kind of cages, and 2. The spin-spin relaxation(representing the coherence time scale) is determined by nuclear spin diffusion andat low temperatures is strongly enhanced by dynamic processes like rotation of themethyl groups. Based on these findings we anticipate that the chemical modificationof the cage organic substituents (e.g. perdeuteration) will give relaxation timescomparable to TM=160 μs of 15N@C60 which is the longest electron spin coherencetime of any molecular radical.

Number of publications in peer-reviewed journals: 7Number of publications in conference proceedings: 17Number of Funded research Programs: 2Number of invited talks: 3

Selected publications1. Sacrificial Template-Directed Fabrication of Superparamagnetic Polymer

Microcontainers for pH-Activated Controlled Release of DaunorubicinA. Chatzipavlidis, P. Bilalis, E. K. Efthimiadou, N. Boukos, and G. C. Kordas.Langmuir, 2011, pp 8478–8485.

This paper presents the synthesis, characterization and release properties of newpH-sensitive nanocontainers. The advantage of this study is the pH response of thenanocontainers and the specific pH release.

2. New approach in synthesis, characterization and release study of pH-sensitivepolymeric micelles, based on PLA-Lys-b-PEGm, conjugated with doxorubicinEfthimiadou, E.K., Tapeinos, C., Bilalis, P., Kordas, G.. Journal of NanoparticleResearch 2011, 13 (12), pp. 6725-6736.

A novel approach for micelle synthesis was presented in this paper. Amphiphilicblock copolymers are well established as building blocks for the preparation ofmicellar drug carriers.


AwardsE.K. Efthimiadou, best poster award for “Thermo, pH and redox sensitivemicrocontainers for drug delivery systems: Release studies”, IC4N 2011, 26-29 June2011,Crete, Greece

Published Conference Proceedings1. Kartsonakis I.A., Balaskas A.C., Karatzas A.E., Kordas G.C.

Improvement of Anticorrosion Properties of Epoxy Coatings on Steel withNanocontainersEUROCORR 2011 "Developing Solutions for the Global Challenge", 4 to 8September 2011 in Stockholm, Sweden

2. Balaskas A.C., Kartsonakis I.A., Karatzas A., Kordas G.Effect of Loaded Inorganic Nanocontainers Into Epoxy Coatings For Protection ofAA 2024-T3 Against CorrosionEUROCORR 2011 "Developing Solutions for the Global Challenge", 4 to 8September 2011 in Stockholm, Sweden

3. Balaskas A.C., Bilalis P., Karatzas A., Kartsonakis I.A., Kordas G.Epoxy Coatings with pH sensitive Organic Nanocontainers Loaded with Inhibitorsfor Protection of AA 2024-T3 Against CorrosionEUROCORR 2011 "Developing Solutions for the Global Challenge", 4 to 8September 2011 in Stockholm, Sweden

4. Kartsonakis I.A., Balaskas A.C., Kordas G.C.Improvement of Anticorrosion Properties of Epoxy Coatings on Steel withNanocontainers3rd International Conference on Self-Healing Materials (3rd ICSHM 2011), 27th-29th

June 2011,Bath, United Kingdom, Book of Abstracts, p. 97

5. Kartsonakis I.A., Balaskas A.C., Kordas G.C.Improvement of Anticorrosion Properties of Epoxy Coatings on Steel withNanocontainers“ICEAF II, 2nd International Conference on Engineering against Fracture”, 22-24June 2011, Μykonos, Greece

6. Balaskas A.C., Kartsonakis I.A., Kordas G.Influence of Loaded Nanocontainers on Epoxy Coatings for Protection of AA 2024-T3 against Corrosion“ICEAF II, 2nd International Conference on Engineering against Fracture”, 22-24June 2011, Μykonos, Greece

7. Kordas G.C., Balaskas A.C., Kartsonakis I.A., Efthimiadou E.C., Mitrikas G.A Raman study of 8-hydroxyquinoline release from loaded TiO2 nanocontainers

“ICEAF II, 2nd International Conference on Engineering against Fracture”, 22-24June 2011, Μykonos, Greece


8. Kartsonakis I.A., Balaskas A., Karatzas A., Kordas G.Improvement of Anticorrosion Properties of Hybrid Organic-Inorganic Coatingson Magnesium Alloys with Nanocontainers, “XIV International Sol-GelConference”, Aug. 28 – Sept. 2, 2011, Hangzhou

9. Haralambos Hatzikirou, Lolas G., Dragatogiannis D.A., Charitidis C.A., KartsonakisI.A., Kordas G.A review on multiscale modeling in complex biological systems: the tumor growthparadigm,Proc. 7th GRACM Int. Con. on 'Computational Mechanics', Athens, Greece, 30June - 2 July 2011, National Center for Research 'Demokritos', Book of Abstracts,Page 46.

10. Mitrikas G, Kordas G.Pulsed EPR characterization of encapsulated atomic hydrogen inoctasilsesquioxane cagesEUROMAR 2011, 21-25 August 2011, Frankfurt am Main, Germany, p. 50 in thebook of abstracts.

11. Chatzipavlidis A., Bilalis P., Mitrikas G., Boukos N., Kordas G.Electron magnetic resonance studies of magnetic nanoparticles encapsulated innovel multifunctional microcontainersEUROMAR 2011, 21-25 August 2011, Frankfurt am Main, Germany, p. 159 in thebook of abstracts.

12. Efthimiadou, E.K., Karaliota, A., Bilalis, P., Chatzipavlidis, A., Tapeinos, G. C,Kordas, G. C.Paramagnetism in Drug Delivery Systems: BioapplicationsFourth North America-Greece-Cyprus Workshop on Paramagnetic Materials,Patras, Greece, June 14-18, 2011, p. 43 in the book of abstracts.

13. Mitrikas G.Quantum computing with hybrid electron-nuclear spin systemsFourth North America-Greece-Cyprus Workshop on Paramagnetic Materials,Patras, Greece, June 14-18, 2011, p. 69 in the book of abstracts.

14. Bilalis, P., Efthimiadou, E. K., Chatzipavlidis, A., Boukos, N., and Kordas, G. C.Novel multifunctional microcontainers: synthesis, properties evaluation and invitro loading and release Daunorubicin testsIC4N 2011, Crete, Greece, 26-29 June, 2011, p. 8 in the book of abstracts.

15. Efthimiadou, E.K., Kordas, G.C.Smart Nanoparticles as new Drug Delivery Systems: Bioapplications.IC4N 2011, Crete, Greece, 26-29 June, 2011, p. 5. Oral Presentation.

16. Efthimiadou, E.K., Bilalis, P., Tapeinos, G.C., Boukos, N., Kordas, G.C. Thermo, pHand Redox sensitive microcontainers for drug delivery systems : Release Studies


IC4N 2011, Crete, Greece, 26-29 June, 2011, p. 29 in the book of abstracts.

17. Bilalis, P., Efthimiadou, E.K., Chatzipavlidis, A., Boukos, N., Kordas, G.C. Novelmultifunctional microcontainers: synthesis, properties evaluation and in vitroloading and release Daunorubicin tests.IC4N 2011, Crete, Greece, 26-29 June, 2011, p. 28 in the book of abstracts.

Active Externally Funded research Programs1. FP7 IDEAS Grant ERC, “NANOTHERAPY, A Novel Nano-container drug carrier for

targeted treatment of prostate cancer”, DG RTD/S2/AMH/cv/D(2008)558627,Project Number 232959

2. FP7 Collaborative Project “MUST” (“Multi-Level Protection of Materials forVehicles by “SMART” Nanocontainers” EC Grant Agreement Number NMP3-LA-2008-214261)

Conference Participation1. Kartsonakis, I.A.

EUROCORR 2011 "Developing Solutions for the Global Challenge"Improvement of Anticorrosion Properties of Epoxy Coatings on Steel withNanocontainers (oral), 4-8 September 2011, Stockholm, Sweden

2. Balaskas, A.C.EUROCORR 2011 "Developing Solutions for the Global Challenge"Effect of Loaded Inorganic Nanocontainers Into Epoxy Coatings For Protection ofAA 2024-T3 Against Corrosion (oral), 4-8 September 2011, Stockholm, Sweden

3. Kordas, G.C.3rd International Conference on Self-Healing Materials (3rd ICSHM 2011)Improvement of Anticorrosion Properties of Epoxy Coatings on Steel withNanocontainers (oral), 27-29 June 2011,Bath, United Kingdom

4. Kartsonakis, I.A.“ICEAF II, 2nd International Conference on Engineering against Fracture”Improvement of Anticorrosion Properties of Epoxy Coatings on Steel withNanocontainers (oral)22-24 June 2011, Μykonos, Greece

5. Balaskas, A.C.“ICEAF II, 2nd International Conference on Engineering against Fracture”Influence of Loaded Nanocontainers on Epoxy Coatings for Protection of AA 2024-T3 against Corrosion (oral), 22-24 June 2011, Μykonos, Greece

6. Kordas, G.C.“ICEAF II, 2nd International Conference on Engineering against Fracture”


A Raman study of 8-hydroxyquinoline release from loaded TiO2 nanocontainers(oral),22-24 June 2011, Μykonos, Greece

7. Mitrikas, G., “EUROMAR 2011, Magnetic Resonance Conference”Electron magnetic resonance studies of magnetic nanoparticles encapsulated innovel multifunctional microcontainers (poster)21-25 August 2011, Frankfurt am Main, Germany

8. Efthimiadou, E.K., “3nd International Conference from nanoparticles andnanomaterials to nanodevices and nanosystems, 3nd IC4N”, Smart Nanoparticlesas new Drug Delivery Systems: Bioapplications. Presentation (Oral) 26-29 June2011, Crete, Greece

9. Angelopoulou A., International Conference on the Chemistry of Glasses andGlass-Forming Melts, Oxford 4-8 September 2011. An insight into the GermanateAnomaly: A comparative EPR and RAMAN study supported by DFT simulations.(oral), 4-8 September 2011, Oxford, UK

10. Angelopoulou A., International Conference on the Chemistry of Glasses andGlass-Forming Melts, Evolution of P environment in 45S5 Bioglass during the firststage of HA formation. (Oral) , 4-8 September 2011, Oxford, UK

Invited Talks1. Mitrikas, G.

“Pulsed EPR characterization of encapsulated atomic hydrogen inoctasilsesquioxane cages”, “EUROMAR 2011, Magnetic Resonance Conference”,21-25 August 2011, Frankfurt am Main, Germany

2. Mitrikas, G., „Quantum computing with hybrid electron-nuclear spin systems”,“Fourth North America-Greece-Cyprus Workshop on Paramagnetic Materials”14-18 June 2011, Patras, Greece

3. Efthimiadou, E.K.Paramagnetism in Drug Delivery Systems: Bioapplications“Fourth North America-Greece-Cyprus Workshop on Paramagnetic Materials”14-18 June 2011, Patras, Greece

Teaching and Training Activities1. Mitrikas, G.

“Hybrid electron-nuclear spin systems and quantum computers”, 50 min talk inthe framework of the Summer School 2011 lectures of NCSR Demokritos, 4-15July 2011

2. Ioannis Kartsonakis“Development and Characterization Techniques of Nanomaterials”


Section III Materials Science and Technique, Τομέας ΙΙΙ National TechnicalUniversity of Athens, School of Chemical Engineering,August 2011 - February 2012

3. Eleni K. EfthimiadouBiomaterials, 5 April 2012, National Technical University of AthensSchool of Chemical Engineering,9 Heroon, Polytechniou St., Zografos, Athens, GR-157 80, Greece

Research ConsultationG. KordasSynthesis of Materials, Petrocoll2001-present


ADVANCED CERAMICS LABORATORY

Research Director: Dr George Vekinis

Permanent Research Staff: Dr Galina Xanthopoulou

PhD Candidates: Ms Amalia Marinou

Masters students: Ms Niovi Athanasakou, Mr Savvas Varitis

External Collaborators:Prof. Osamu Odawara, Dr Nastaran Tamjidi, Prof. Seiichi Hata (Tokyo Institute ofTechnology, Japan)Dr Jean-Marc Bouilly (ASTRIUM, France)Dr Alexander Sytchev (ISMAN, Russia)Prof. Alexander Mukasyan, Univ. Notre Dame , USA

Visiting Researchers: Prof./Drs: Odawara, Tamjidi, Hata, Sytchev and Mukasyan

Areas of Research: Advanced materials and systems for space and planetary exploration Advanced functional ceramics and oxide catalysts Combustion synthesis of materials Microwave processing of materials

Activities and Achievements:

1. Advanced materials and systems for space and planetary explorationThis is our main area current of research and the most successful in terms of fundingand projects won.a) Within the EC FP7/Space project “Rastas Spear”, (http://www.rastas-spear.eu/)we are studying the thermal and mechanical properties of the new ablative thermalprotective material ASTERM (supplied by coordinating partner EADS/ASTRIUM,France) which is used for the protection of “sample-return” space probes returningat high speed through the earth’s atmosphere.


Figure 1. Schematic of a sample-return probe with its thermal protective shield(left) bringing a soil sample back from a planet at high speed through the

atmosphere.

A thermal protective system is necessary for returning spacecraft as thetemperatures generated by atmospheric friction reach plasma levels. The thermalflux depends on many parameters (geometry, speed, angle of approach, type ofatmosphere etc) and can reach 30MW/m2 with the total heat energy (over about 20-30 seconds of travel) of about 700MJ/m2. No material can withstand such energieswithout vapourizing, so the thermal protection used is sacrificial, i.e. it ablates andabsorbs some of the heat energy by its latent heat of vapourisation. ASTERM is anew material made of carbon fibres in a phenolic matrix and we studied itsbehaviour and that of adhesive joints and bonds before and after plasma-jet (highspeed plasma) testing at the Sirocco facility at CIRA, Italy and some of the results areshown in Figures 2 and 3.

Figure 2. Cross-section of an ASTERM TPS after plasma testing.

Cross section of an adhesively joined ASTERM (supplied by EADS/ASTRIUM) specimen afterPlasma jet testing at 5MW/m2 for 12 seconds at the Sirocco facility at CIRA. Total recession at top is

about 2mm, it is fairly uniform and <0.5mm on the sides. Charred region varies from 6 to 12mm.Recession of the adhesive is slightly larger (photo on top left). The adhesive used was an RTV

Silicone elastomeric rubber mixed with small amount of ASTERM powder

ASTERM-adhesive interfacein charred region

Virgin ASTERM-adhesiveinterface

ASTERM-loadedadhesive incharredregion

The ASTERM-loaded adhesive

remained wellbonded after

testing withminimal additional

recession

ASTERM in charred region

Virgin ASTERM


b) Studies on our own patented TPS system, the “Hybrid TPS” which we developedpreviously with European Space Agency (ESA) support during 2007-2008 continuedin 2011. The difference with ordinary ablative TPS is the existence of a hard ceramicsubstructure which offers protection against impinging high speed particles(micrometeorites and space debris) in addition to the ablative thermal protectionfiller.c) Studies on in-situ resource utilization (ISRU) of materials on the surface of themoon and planets also continued in 2011. In particular, we studied solidification ofregolith soil simulant based on ilmenite and chromite using the combustionsynthesis method (self-propagating high-temperature synthesis, SHS). The studieshave shown that it is possible to produce hard, strong structural blocks from suchsoil raw materials without the need of atmospheric oxygen. The work is continuingwith synthesis studies in vacuum. The work is being carried out in collaboration withTokyo Institute of Technology, Japan and ISMAN, Russia. A proposal for furtherstudying of the regolith simulant was unsuccessful at ESA/ESTEC.d) During 2011, a new shielding composite system was designed in our lab (patentapplied for) for protection of humans from the dangers posed by high energycharged particles in space such as Solar Proton Events (SPE) and Galactic CosmicRays (GCR). While the earth is shielded mainly by its atmosphere and its magneticfield, space travelers are exposed and any long-term habitation or travel in openspace will only become feasible if methods are found to shield humans from theseDNA-damaging particles.The new composite system “CosmicRayShield” consists of a hydrogen-enrichedpolyethylene matrix containing magnetic micro and nanoparticles. Simulations haveshown that any penetrating charged particles will be acted upon and deviated fromtheir trajectory by the magnetic and electric (plasma) fields of the magnetic particles,as shown in the schematic in Figure 5. After many such interactions, the particleslose some of their energy and are more easily absorbed by a final collision with ahydrogen nucleus. A EC/FP7/Space proposal (supported by the main Europeanmanufacturer of spaceships, ThalesAleniaSpace) was submitted in Nov 2011 which

Bending strength of ASTERM before and after plasma tests at 5MW/m2

0.00

0.50

1.00

1.50

2.00

2.50

3.00

VirginASTERM,

loading verticalto fibres

Top char,loading vertical

to fibres

VirginASTERM, side,

spec. cuthorizontally

Side char,spec. cut

horizontally

VirginASTERM, side,

spec. cutvertically

Side char,spec. cutvertically

Tran

sver

se R

uptu

re S

treng

th, M

Pa

Figure 3. Bending strength ofcharred ASTERM from the topand the side surface (specimenscut both horizontally andvertically) in comparison withthe strength values measuredon similar sized specimens onvirgin ASTERM


succeeded in passing all thresholds but was not retained for funding and will beresubmitted in 2012.

Figure 5. Schematic of the “CosmicRayShield” illustrating the micromechanisms of deviationof High energy charged particles by the action of the magnetic particles in a hydrogen-

enriched polyethylene matrix.

e) An FP7/Space proposal for the project (“PULCHER”) coordinated by ALTA Space(Italy) to develop a new propulsion method for spacecraft was prepared andsubmitted in Nov 2011 and was retained for funding. We have a critical contributionfor the development of the new high temperature combustion chamber. The projectis expected to commence in Oct 2012.f) A new FP7/Space project “HYDRA” (coordinated by TECNALIA, Spain) to develop alayered ceramic-ablator TPS, where our contribution is on the mechanicalcharacterization of the material, was also submitted and approved in 2011 andstarted in March 2012.

2) Inorganic heterogeneous catalysts

Our work on the development of new catalyst systems for industrial andenvironmental applications using combustion synthesis, especially SHS, continued in2011. The main catalysts studied were firstly in the system Co-Ni-Mn-O for CO2

reforming of methane and secondly in the system Ni-Al-O for hydrogenation ofunsaturated hydrocarbons. In both cases, the catalysts were synthesized using theSHS method and the work is continuing.

A range of nano-structured cobalt-based inorganic pigments were developed for thefirst time by Solution Combustion Synthesis (SCS). The new pigments have very wideindustrial applicability and efforts are being made for their industrial application. In

AnisotropicMNP’s

HDPE (nCH2)matrix (with

hydrides, notshown)

Incident high energy charged particles


addition, a range of inorganic pigments based on wollastonite have been developedfor use in the plastics and paper industries.

3) NiAl-based high temperature sprayed coatings for stainless steel

A new activity based on our previous studies on the combustion synthesis ofintermetallic phases in the Ni-Al and Ni-Al-O systems was initiated during 2011. Itwas found that it is possible to produce high integrity coatings of NiAl intermetallicson stainless steels for thermal and corrosion protection, using an ordinary flamespray coating gun and inexpensive Ni and Al powders as starting materials instead ofexpensive pre-alloyed powders. The novelty of the method is the “in-flight”combustion (akin to SHS) exothermic reaction of the powders to produceintermetallics during their transit time from the gun to the substrate. Mainadvantages of this method are its ease of application, its low cost and the capabilityfor producing a range of intermetallics, ideal for repairs of turbine blades etc. Thetechnology is new, at least in terms of the use of the low cost, hand-held acetyleneblow-torch and the coatings have shown very good properties, as good as or evenbetter than with ordinary coatings using expensive pre-allowed powders, as shownin Figure 4.

Ni, NiOAl, Al2O3

Al3Ni, NiAl

Figure 4. Ni-Al coatingsmade by in-flight SHS flamespray coating of stainlesssteel. The coatings are verywell formed and in manycases better than thosemade by expensive pre-allowed powders.


An RD proposal for further development of the new technology was submitted toFP7 with many industrial and academic partners was submitted in Nov 2011,unsuccessfully, and will be re-submitted in 2012.

4. Microwave processing of industrial materials and productsOur work on developing new industrial applications of Microwave irradiation ofindustrial minerals, ceramics, lignite and solid or semi-solid wastes continued during2011.In many cases, it is possible to reduce drying time with Microwaves by as much as75% which reduces the overall production time and cost significantly. The technologyis mainly applied by our spin-off company, AIT SA (Thessaloniki) while our lab retainsthe proof of concept capabilities in each case. On-going negotiations during 2011involved the Public Power Corporation and the S&B mining company on Milos Island,Greece.

Published Conference Proceedings1. Xanthopoulou G, COMBUSTION SYNTHESIS OF MATERIALS ADDRESSES

CURRENT AND FUTURE INDUSTRIAL CHALLENGES, Plenary Talk, the 11th SHSInternational Symposium on SHS, Anavyssos, Greece, 5-9 September 2011.

2. Marinou A, Xanthopoulou G, Vekinis G, Lekatou A, Vardavoulias M,COMPOSITE COATINGS IN THE SYSTEM AL-NI-NIO BY IN-FLIGHT COMBUSTIONSYNTHESIS DURING THERMAL SPRAYING Proceedings of the 11th SHSInternational Symposium on SHS, Anavyssos, Greece, 5-9 September 2011.

3. Arvanitis K, Xanthopoulou G, Vekinis G, Zoumpoulakis L, Katsaros T andGanetsos T, SHS PRODUCTION OF STRUCTURAL UNITS OF LUNAR REGOLITHSIMULANT, Proceedings of the 11th SHS International Symposium on SHS,Anavyssos, Greece, 5-9 September 2011.

4. Athanasakou N S, Xanthopoulou G, Vekinis G and Zoumpoulakis L, PIGMENTSON THE BASIS OF Cr-, Mn- AND Co-MODIFIED WOLLASTONITE FORINDUSTRIAL APPLICATIONS, Proceedings of the 11th SHS InternationalSymposium on SHS, Anavyssos, Greece, 5-9 September 2011.

5. Marinou A, Xanthopoulou G, Vekinis G, HIGHLY ACTIVE Cu–Cr–O MIXEDSPINEL SHS CATALYST FOR THE OXIDATION OF CO, Proceedings of the 11th

SHS International Symposium on SHS, Anavyssos, Greece, 5-9 September2011.

6. Pagonis N, Xanthopoulou G, Vekinis G, Polymenis S, SHS OF Mo-BASEDHYDROGENATION CATALYSTS, Proceedings of the 11th SHS InternationalSymposium on SHS, Anavyssos, Greece, 5-9 September 2011.

7. Thoda O, Xanthopoulou G, Vekinis G, Zoumpoulakis L., Boukos N, SOLUTIONCOMBUSTION SYNTHESIS OF COBALT PIGMENTS, Proceedings of the 11th SHSInternational Symposium on SHS, Anavyssos, Greece, 5-9 September 2011.

8. Xanthopoulou G and Vekinis G JOINING OF SiC, MgO, MgAl2O4 AND FERROUSMETALS USING SHS, Proceedings of the 11th SHS International Symposium onSHS, Anavissos, Greece, 5-9 September 2011.


9. Vekinis G, “Strategy development for the transfer of new technologies toindustry: converting a clever Invention to a valuable Innovation", PlenaryTalk, 11th SHS International Symposium on SHS, Anavissos, Greece, 5-9September 2011

10. Xanthopoulou G, “Combustion Synthesis of Spinels for wide rangeapplication”, Int. conference on Nonisothermal Phenomena & Processes:From Thermal Exploision Theory to Structural Macrokinetics, ISMAN,Chernogolovka, Russia, Nov. 2011.

11. Bouilly J-M, Pisseloup A, Chazot O, Vekinis G., Bourgoing A, Chanetz B, SladekO, “RASTAS SPEAR”, 3rd International ARA Days - Arcachon, France, May 2-42011

12. Bouilly J-M, Pisseloup A, Chazot O, Vekinis G, Bourgoing A, Chanetz B, SladekO, “RASTAS SPEAR”, FP7 Space Conference 12-13 May 2011

13. Bouilly J-M, Pisseloup A, Chazot O, Vekinis G, Bourgoing A, Chanetz B, SladekO, “RASTAS SPEAR”, 8th Int. Planetary Probe Workshop, Portsmouth, VA, USA,June 6-10, 2011

Active Externally Funded research ProgramsFP7/Space, “Rastas Spear”, 2010-2012, 270kEuro for NCSRD

Conference Organisation11th International Symposium on SHS, 5-9 September 2011 Anavissos, Greece. Co-Chairperson: Dr Galina Xanthopoulou, Deputy Chairperson, Dr G. Vekinis

Conference Participation1) 11th SHS International Symposium on SHS, 5-9 September 2011 Anavyssos,

Greece.2) Int. conference on Nonisothermal Phenomena & Processes: From Thermal

Explosion Theory to Structural Macrokinetics, Chernogolovka, Russia,November 2011.

Invited Talks1) Xanthopoulou G., “SHS, A New Class of Combustion Processes for Materials

Production”, Department of Innovative and Engineering Materials, TokyoInstitute of Technology, Tokyo, Japan, 21 September 2011

2) Xanthopoulou G., “PROSPECTIVES OF SHS DEVELOPMENT”, Department ofInnovative and Engineering Materials, Tokyo Institute of Technology, Tokyo,Japan, 27 September 2011

3) Xanthopoulou G., “SHS, a New Class of Combustion Processes for MaterialsProduction”, Ryukoku University, Kyoto, Japan, 30 September, 2011

4) Xanthopoulou G., “Environmental applications of SHS”, Department ofInnovative and Engineering Materials, Tokyo Institute of Technology, Tokyo,Japan, 3 October 2011

5) Xanthopoulou G., “SHS for Space”, Department of Innovative and EngineeringMaterials, Tokyo Institute of Technology, Tokyo, Japan, 6 October 2011


6) Xanthopoulou G., “OVERVIEW OF COMBUSTION SYNTHESIS MATERIALS FORCATALYSIS”, Center for Advanced Research of Energy Conversion Materials,Hokkaido University, Supporo, Japan, 13 October 2011

Teaching and Training Activities1) Xanthopoulou G., student training and preparation of post-graduate book on

“FINE OXIDE POWDER COMBUSTION SYNTHESIS FOR CATALYST AND ENERGYMATERIAL DEVELOPMENT”, JSPS Invitation Fellowship for Research in Japan,at Tokyo Institute of Technology, Japan, September 19 - October 22, 2011

2) Vekinis G., “Advanced Ceramics”, course of lectures at the Department ofPhysics, Aristotelian University of Thessaloniki, Greece, June 2011

Degrees completed in 2011Athanasakou N.S, “Production of wollastonite pigments for different application andstudy materials properties with those pigments”, supervised by: G. Xanthopoulou, G.Vekinis and L. Zoumboulakis (NTUA), Department of Chemical Engineering, NTUA,Greece.

Consultation activities:Vekinis G., Exploitation Strategy and Innovation Management, EC/DG Research,Brussels, Belgium, 2011.


RADIOCARBON DATING AND PROVENANCE OF BIOLOGICALAND LITHIC

LUMINESCENCE DATING AND SOLID STATE DOSIMETRY

PALEOENVIRONMENT AND ANCIENT METALS

CERAMICS AND COMPOSITE MATERIALS

STABLE ISOTOPE UNIT

RESEARCHERS

Y. Bassiakos, E. Dotsika, A. Hein, V. Kilikoglou, Y. Maniatis , Ch. Michael

RESEARCHER OFFICERS

I.Karatasios, E. Filippaki

TECHNICAL STAFF

M.E. Kyriazi, P. Karalis

PROJECTS

PROGRAM IIIARCHAEOMETRY

PERSONNEL



N. Mueller

PhD STUDENTS

D. Tambakopoulos, M. Skordara, M. Mexi, I. Tzavidopoulos, M. Maniati, A. Zianni, I.Margaritis, Ch. Tselios, M. Papageorgiou, M. Kaparou, K. Karaindrou, D. Oikonomou,G. Mastrotheotoros, M. Kazantzaki, S. Mavroulis, E. Tsakalos, M. Tziotziou, L.Farmakalidou, E Ampatzioglou, N. Zisi, D. Kyropoulou, M. Bakas


RADIOCARBON DATING AND PROVENANCE OF BIOLOGICAL AND LITHICMATERIALS

Research Director: Y. Maniatis

PhD Candidates: D. Tambakopoulos, M. Skordara, I.Tzavidopoulos, M. Maniati

Masters Students: Th. Arvaniti, N. Politi

Diploma Students: E. Lariou

Technical Personnel: M.E. Kyriazi

External Collaborators:Prof. Colin Renfrew, Cambridge University; Dr. B. Kromer, University of Heidelberg;Prof. M.S. Tite, Oxford University; Dr. Zoi Tsirtsoni, Lyon; Prof. Ch. Paliadeli, Dr. E.Papadopoulou, Aristotle University of Thessaloniki; Dr. S. Papadopoulos, 18th

Ephorate, Ministry of Culture; Prof. C. Doumas, Archaeological Excavations ofAkrotiri; Ch. Ziota, Λ’ Ephorate, Ministry of Culture; Dr. J. Coltrain, University ofUtah; Prof. T. Cerling, University of Utah.

Areas of Research: High precision radiocarbon dating of cultural and environmental materials. Investigation of human paleodiet. Development of methodologies and databases for the provenance of marble

sculptures and monuments. Characterisation of provenance and technology of early vitreous materials and

paintings.

Activities and Achievements:Radiocarbon dating● Through the project BALKANS 4000, funded by the ANR of France, we investigatedsystematically the occupation gap, detected earlier by our laboratory, which occursin the 4th millennium BC in N. Greece and the Balkans. The new measurementsshowed that the gap lasts for 700-1000 years and that the Late Neolithic II period didnot last from 4800 to 3300 BC as it was thought but it suddenly stops at about 4000BC (Fig. 1) when people abandon their regular settlements and perhaps went on anomadic? way of living. The settlements were occupied again in 3300 BC, theearliest, by new people that brought the Early Bronze Age culture that spreadaround Anatolia, Greece and the Balkans.


Figure 1. Radiocarbon dates from a largenumber of sites from N. Greece. Theserious lack of dates in the periodbetween 4000-3300 BC is evident(Maniatis et al in press). Agios Ioannis ofThasos is probably an exception to thispattern contributing some dates in theabove gap (Maniatis and Papadopoulos2011).

● The investigation by radiocarbon dating and Bayesian analysis of the chronologicalsequence of a unique prehistoric cemetery at Xeropigado in Kitrini Limni near Kozanirevealed that the cemetery was in continuous use for about 700 years (2420-1730BC) and that the new burials never disturbed the old ones (Maniatis and Ziota 2011).We found also periods of more intense use at 2200-2030 BC and 2000-1850 BCwhich would mean either a population growth or some epidemics. Furthermore,there was no geographical differentiation during time, but the whole area of thecemetery (1500 sq.m) was used concurrently in all periods.

Figure 2. Calibrated dates with probability distribution forXeropigado (Kitrini Limni, Kozani) cemetery, showing thewhole time span and the periods of more intense use(Maniatis and Ziota 2011).

● A new approach was applied for determining the time of eruption of the Theravolcano and the destruction of the Late Cycladic settlement at Akrotiri. It was shownthat the houses of the last phase (LCI) were build around 1740 BC, more than 100years earlier than estimated by historical dating (1600 BC), and the eruption musthave occurred at 1640-1600 BC, also 100 years earlier than estimated by historicaldating (1530 BC) (Maniatis 2012).


Provenance of marble● A long standing and demanding project aiming at determining the provenance of

560 Cycladic figurines found on Keros during the excavations directed by Prof. ColinRenfrew was completed in 2011. It involved the development of a new data baseand methodology, based on the combination of Electron Paramagnetic Resonancespectroscopy, Stable Isotope Ratio (13C/12C και 18O/16O) analysis, Maximum GrainSize measurements and crystalline parameters, in order to discriminate the marblebetween the various Cycladic islands (Ph.D. dissertation, D. Tambakopoulos). Theresults indicate that the vast majority of the Keros figurines come from Naxos andspecifically from areas in South-east Naxos and Central-east Naxos (Fig. 3).

Figure 3. The Keros figurines (different symbols for different varieties) against the Cycladic marblegroup databases (EPR, Maximum Grain Size and Stable Isotopes)

Two large Chapters were written for the forthcoming Keros-Dhaskalio multi-volume publication: One on the provenance of figurines and vessels and a second onthe weathering degree and excavation location of the figurines.

● A large project on the marble provenance of 35 sculptures at the Lyon and VienneGallo-Roman Museums in France was completed in 2011.

Vitreous Materials TechnologyThe investigation of the technology of ancient vitreous materials such as faience andglazed steatite beads focused on laboratory simulation experiments aiming atunderstanding the physical and mineralogical changes occurring in steatite byheating. Also, the investigation and treatment of the analytical results obtained forglass vessels and window panes from the site of Philippoi in East Macedonia leads tounderstaning the glass making and glass working of the Early Christian period (Ph.D.dissertation, M. Skordara).

Human Diet and Food PreparationThis investigation involves: 1) tracing of the stable isotope ratios of δ13C and δ15Ν inhuman bone collagen; they reflect the percentage of different food sourcesconsumed (terrestrial, marine, plant, animal), and 2) the study of the cooking devicesfound in excavation; they reflect the ancient food technology. Regarding the first,studies on the Kaiadas human bones and from burials in the city of Sparta itself and


Laconia provided an interesting data which is now under treatment for publication(Ph.D. dissertation, M. Maniati). Regarding the second, the thermal properties ofvarious domestic clay structures (oven, hearths, composite structures) from the EBAsite of Archontiko Yannitson were investigated using FTIR spectroscopy, as well as,XRD and SEM. The top temperatures which these structures reached and the timesof heating were estimated from the temperature gradients through their walls andfloors. The nature and use of each of those devices was estimated. Among theunusual and exceptional finds was a composite device apparently used for smokingof food (Fig. 4, centre) (Papadopoulou and Maniatis in print).

Figure 4. Food preparation clay structures at Archontiko Yannitson (left), FTIR spectra across the wallof an oven (right).

Active Externally Funded research Programs1. Agence National de la Recherche France, Programme Jeunes Chercheuses et

Jeunes Chercheurs – 2007. “BALKANS 4000 : A la recherche du millénaire perdu:le peuplement en Grèce du Nord et dans les Balkans au IVe millénaire av. J. -C."(N ° réf.: ANR_R_0802.03). Coordinator: Dr. Z. Tsirtsoni, and for NCSR“Demokritos”: Y. Maniatis. Total Funding for 4 years: 120,000 €.

2. Program THALIS (2011-2015): “The Apollo Sanctuary and the Late RomanSettlement in Halasarna (Kos). The history of an ancient sanctuary, its declineand its final transformation into a Late Roman/Early Christian settlement”,Coordinator: G. Alevra, University of Athens, and for NCSR “Demokritos”: Y.Maniatis. Total funding: 600,000 € (50,000 € for “D”).

Invited TalksManiatis, Y.The marble over the centuries as a material for the religion, the art and thearchitecture: Its travel in the Aegean and from Rhodes to Samothrace (in Greek)University of the Aegean, Lodging of the Language of Spain, Nights Street, Old City,Rhodes, Wednesday, 4 May, 2011.

Teaching and Training ActivitiesManiatis, Y.Dating Methods in Archaeology - Carbon-14


Aristotle University of Thessaloniki, Faculty of Engineering. Inter-departmentalpostgraduate program: Protection, Conservation, and restoration of CulturalMonuments".

Maniatis, Y.Characterization, provenance and movement of marble in AntiquityAristotle University of Thessaloniki, Faculty of Engineering, Inter-departmentalpostgraduate program: Protection, Conservation, and restoration of CulturalMonuments".

Maniatis, Y.1. Cultural heritage and Physical Sciences: Definitions and aims2. Radiocarbon: A continuous revolution in the chronometry of the cultural

evolutionNational Centre for Scientific Research “Demokritos”, Summer School, 4-15 July,2011.

Maniatis, Y.Radiocarbon dating in ArchaeologyNARNIA (New Archaeological Research Network for IntegratingApproaches), Training Course Program (21/11/2011-25/11/2011).

Degree Diploma projects completed in 2011Eirini LariouDetermination of the provenance of marble from ancient monuments with PhysicalSciences methodsResearch Supervisor at NCSR “D”: Y. ManiatisSchool of Applied Mathematical and Physical Sciences, National Technical Universityof Athens, October 2011


LUMINESCENCE DATING AND SOLID STATE DOSIMETRY

Research Director: C.T. Michael

Permanent Research Staff: C.T. Michael

Diploma Students: M. Kontos

External Collaborators: National Technical University, Chemical EngineeringDepartment; University of Peloponnese, Department of History, Archaeology andCultural Resources Management; University of the Aegean, Department ofMediterranean Studies; Greek Atomic Energy Commission.

Areas of Research: Development of new techniques for luminescence dating and authenticity of

archaeological, geological and paleontological materials. Environmental dosimetry and development of new techniques in the field of

microdosimetry for the calculation on natural radioactivity (U and Th seriescontent) using phosphors and solid state detectors (TL, PIPS, etc).

Activities and Achievements:Summary of Objectives and Achievements

During the last year, 2011, the potential applications of thick source alphaparticle spectroscopy to radiation measurements beyond luminescence (TL, OSL) andESR dating were investigated, using the new technique of U and Th concentrationestimation. For this technique up to now four papers in international journals havebeen presented and one recent is in press (C.T. Michael and A. Hein, High SensitivityRadioactivity Measurements by Using Thick Source Alpha Particle Spectroscopy(2012) Applied Radiation and Isotopes). In the recent years this technique wasstudied and improved particularly in terms of determining and eliminating sources ofinaccuracy. During this study the estimated systematic error was considerablyminimized reaching to lower than 0.05 ppm for U and 0.12 ppm for Th. Apart fromoptimized radiation measurements in the field of dating the improved techniqueproved to provide the basis for extending the application towards other fields, suchas environmental radioactivity measurements. Examples are Radon estimation, andpotentially isotopic dating by exploiting further the ability of disequilibriumestimation.

Radon estimationIt was noticed that in the alpha- counting spectrum for the first 2 counting days

for many samples, relatively intense peaks of 214Po (U series) and also 212Po and 212Bi(Th series) appear. These peaks do not increase for more counting days and appearin the samples which have been left in a certain environment for some hours or daysuncovered. They are due to the daughter solid nuclides of 222Rn and 220Tn fallen on


the surface of the sample from the atmosphere of this environment. If the countingcontinues for the following days, the counts per day for these peaks decreaserapidly. The rapid decrease of these peaks is expected because their decay isdependent on the longest half life of the successive daughter nuclides of 222Rn and220Tn from which they are coming from. Thus the half life of the 214Po peak is 26.8min corresponding to the half life of 214Pb, since the former is in equilibrium to thelatter, and the half life of 212Bi and 212Po (resulting from branch decay of 212Bi ) peaksis 10.6 h corresponding to that of 212Pb for a similar reason. It is obvious that theintensity of these peaks (214Po, 212Po and 212Bi) depends on the a.c. of 222Rn and220Tn in the atmosphere of the environment in which the samples have left. Thus theintensity of these peaks could be a measure of the 222Rn and 220Tn a.c. in theatmosphere of this environment. The number of 214Po, 212Po and 212Bi nuclides onthe surface of the samples and consequently the intensity of their peaks, reachesand remains to a maximum, when the sample is left in the same environment, afterabout 4 to 5 half lives of the mentioned longest lived nuclides (214Pb and 212Pb),that is about 100 to 140 min for 214Po peak and about 40 to 50 h for the 212Po and212Bi peaks. These time corresponds to the time needed the rate of falling on thesurface of the sample for each one of these longest lived nuclides to become equalto its activity on the surface of the sample. This is about a similar case to that forreaching radioactive equilibrium.

For the a.c estimation of 222Rn and 220Tn in the atmosphere of a certainenvironment an iron disc of very low a.c. ( less than 0.005 Bq/g), 4 cm diameter andabout 2 mm thick is left uncovered on a horizontal surface (Fig. 1) for about 50 h, i.e.two days, because as explained the number of accumulated 214Po, 212Po and 212Binuclides don’t increase for more days in this environment. Then this disc is placedunder the detector and the total numbers of counts in the energy region of each oneof the peaks, corresponding to the above nuclides that is, 7.68, 8.78, and 6.09 Mev,respectively, are counted for two days, since for more days the counts don’t increasesignificantly. This is so because this time corresponds to about 5 half lives of thelongest lived nuclide 212Po of them and thus the counts rate of this nuclide decreasesto the 1/ 25 of its initial value and the decrease of counts rate for the other of thetwo nuclides is faster. Practically the number of counts of 214Po and 212Po peaks arecounted for 2 days, which are a measure of the a.c. of 222Rn and 220Tn, respectively,in the examined environment. By comparing these numbers with the correspondingnumbers taken in an environment of known 222Rn and 220Tn a.c. it is possible tohave an estimation for the a.c. in the examined environment.

In Fig. 2 the spectrums taken from the iron disc placed in a cubic plastic boxof 10 cm edge length (Fig. 1) containing also a plate covered with a powder of 350ppm U and 990 ppm Th concentration (black spectrum) and of the same disc placedin a room of known Radon a.c., which is 30 Bq/m3 (red spectrum) are presented.From the comparison of the numbers of counts in the energy region (7.68 MeV) ofthe 214Po peak in these two spectrums it was concluded that the a.c. of Radon in theplastic box is 220 Bq/m3. It is obvious that this increased Radon a.c. in the plastic boxis expected and the result is very satisfactory.

By this technique we can have a fast and simple estimation of 222Rn and 220Tn inevery environment. This technique has the additional advantage, in comparison tothe usually used methods, of separating the activity of 222Rn from that of 220Tn and


also we have the option of using filters usually used for these measurements. Sincethe duration for a measurement is only 4 days, it can be repeated many times in thesame environment for increasing the accuracy.

Figure 1. Iron disc placed in a plastic box containing a plate covered with a powder of 350 ppm U and990 ppm Th concentration

Figure 2. Spectra taken from the iron disc placed in a plastic box containing a plate covered with apowder of 350 ppm U and 990 ppm Th concentration (black) and of the same disc placed in a room ofknown Radon activity, which is 30 Bq/m3 (red).

0 1 2 3 4 5 6 7 8 9 100,0000,002

0,0040,0060,008

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51 point S-G Smoothing of EEAE2_lusavrite151 point S-G Smoothing of EEAE2_EEAE2ThU

coun

ts/ K

s

Energy (MeV)

220 Bq/m3

30 Bq/m3

214Po

212Po


Conference Participation1. Michael, C.T., Hein, A.

Industrial Radiation and Radioisotope Measurement ApplicationsHigh Sensitivity Radioactivity Measurements by Using Thick Source Alpha ParticleSpectroscopy

June 26 – July 1, 2011, Kansas, USA.

Teaching and Training Activities1. Michael, C.T.

Dating methods with Luminescence and solid state micro-dosimetryNational Centre for Scientific Research “Demokritos”, Summer School, 4-15 July,2011.

2. Michael, C.T.Principles and new techniques in alpha counting and luminescence datingNARNIA (New Archaeological Research Network for IntegratingApproaches), Training Course Programme (21/11/2011-25/11/2011).

Services providedParticipation in the service program: “Ancient Metals and Paleoenvironment”.


PALEOENVIRONMENT AND ANCIENT METALS

Research Director: Y. Bassiakos

Permanent Research Staff: Y. Bassiakos, E. Filippaki

Contract Researchers: C. Athanassas

Post-Doctoral Researchers: -

Visiting Researchers: Prof. Guenther Wagner

PhD Candidates: M. Mexi, A. Zianni, I. Margaritis, Ch. Tselios, M. Papageorgiou, M.Kaparou, K. Karaindrou, D. Oikonomou, G. Mastrotheotoros, M. Kazantzaki, S.Mavroulis, E. Tsakalos.

External Collaborators: C. Xapladeris, K. Theodorakopoulou

Areas of Research:In the frame of this project, basic research and applications being undertaken onarchaeomaterials, fall within the field of Archaeological Sciences. More specifically,under the title ‘Paleoenvironment and Ancient Metals Studies’, the followingsubjects are investigated: a) the development and improvement of theluminescence-based absolute dating techniques, with applications onpaleoenvironmental reconstructions, diachronic evolution of maritime ancientlandscapes, sea-land interactions, associated human actions, and cave evolutionswith cultural importance, b) archaeometallurgical studies (pyrotechnology, smelting,alloying, metals manufacturing, transformation and provenancing, and c) metallicobjects of historical and/or cultural importance treated under reducing low RFplasma conditions, examined towards obtaining reversion of the oxidized/weatheredsurfaces, passivication and deep desalination.

Activities and Achievements:a) Paleoenvironment and luminescence based dating techniques: Implementing

the EU-funded NARNIA research project (New Archaeological ResearchNetwork Integrating Approaches to Ancient Materials Studies,http://narnia-itn.eu/), ancient landscape reconstruction and OpticallyStimulated Luminescence (OSL) studies have been initiated in southernPeloponnese (Mani/Dyros) and in SE Cyprus (Cavo Greco, Aghia Nappa)maritime areas by two PhD candidates-NARNIA fellows, supervised by Y.Bassiakos and C. Athanassas. Moreover, another two doctorate sub-projectsare focusing 1) on the landscape evolution and OSL dating of the AncientMessene (SW Peloponnese) archaeologically excavated site and 2) on theneotectonic/structural regime and OSL dating of the North Euboean Gulf,supervised by Y. Bassiakos and C. Athanassas. Also, original research was


initiated by the currently developing dating technique of CosmogenicNuclides, aiming at absolute dating of prehistoric quarries and human-carvedrocks. Pertinent two months training to the new researcher (C. Athanassas)was offered (January 2011-March 2011) by the Centre Européen de Rechercheet d’Enseignement des Géosciences de l’Environnement, Provence, France.

b) archaeometallurgical studies:A collection of some 160 bronze artifacts which are displayed at the ArchaeologicalMuseum of Chora – Messenia/Peloponnese and the National ArchaeologicalMuseum in Athens were, after sampling, examined under the optical microscope,(Figs 1 & 2), followed by observation under a Scanning Electron Microscope (SEM)equipped with an EDS micro analytical system, in the frame of the PhD study of Ch.Tselios, supervised by E. Philippaki and Y. Bassiakos. The up to date results haverevealed a new and interesting views of the mycenaean metalwork practices as theappearance of the burial offerings is concerned, unknown previously in such extent.Although all the artifacts under discussion are catalogued as bronze finds - they weretreated such as during the course of conservation and restoration - and despite thefact that they bear no visible traces of any other metallic layer, a great number ofthem seem to have been silver plated. Silver plating is mainly attested in the form ofsmall fragments of silver located at the corroded periphery of the samples or incavities and fragmentations near the surface. The technique was applied mainly toweaponry and in a smaller scale to vases and jewelry, most probably in a sort periodbefore inhumation since all the weapons and tools under examination must haveonce been utilitarian, according to the alloys used for their manufacture and theirmechanical treatment. Silver plating was practiced as early as the late 17th or early16th century B.C. at the grave finds of Peristeria site. Slightly later the technique isattested at the artifacts of the cemetery at Volimidia site, during the course of the16th century B.C. and at the tholos tombs of Routsi in the mid 15th century.

Fig. 1 (left): Mycenaean LBA dagger externally corroded, sampled at its cutting edge(indicated). Fig. 2 (right): Microscopic image of the metallographically examined sample(after etching), exhibiting isometric crystallites with twinnings, indicating hot hammeringafter casting.

c) metallic objects under RF plasma conditions and pertinent research:1. Development of new protocol for the restoration and conservation of iron artifacts

recovered from the marine environmentMarine artifacts are notoriously challenging to conserve. Once iron has beenrecovered from a marine environment, the corrosion process is accelerated, unless


certain precautions are taken. The greatest damage is caused by various ironchlorides (ferrous and ferric) found into the recovered artifacts. Hydrated ironchlorides, on exposure to moisture and oxygen, hydrolyse to form ferric oxide orferric hydroxide and hydrochloric acid. The hydrochloric acid in turn, oxidises theuncorroded metal to ferrous chloride and hydrogen, or ferric chloride and water.Desalination treatment is one of the most laborious and time-consumingconservation treatments. A number of marine objects from Paros and Syros islandsand artificially corroded coupons were treated by using either hydrogen plasmareduction or chemical treatment using NaOH solution or a combination of them as acomparison study. It was shown that the treatment by sodium hydroxide solutionfollowing with hydrogen plasma reduction had the best dechlorination results whilethe passivation of the surface was accomplished by the magnetite layer that wasproduced due to the reduction of iron oxides.

Fig 3. Cannon ball from Paros Island before and after its treatment and its desalination diagram.

2. Magnetised Argon plasma into Q-machineA low pressure argon plasma with magnetic restraint is lit in a cylindrical cavity. Theplasma production is based on the rf upper hybrid resonance. A radial dc electricfield is created and a perpendicular drift velocity on the charged particles isappeared as a result of electric and magnetic fields. Due to azimuthal drift, acollisional instability is raised. Studying this physical procedure we concluded to thefollowing results: i) the description, study and identification of the different plasmawaves and their behaviour, ii) the great influence of the boundaries and the initialconditions on the wavy results lead to the understanding of the chaotic state ofplasma. Non linear dynamics and different models and simulations were used toappear the “non predictability” of plasmatic state, iii) a complete answer of the wellknown problem of considering a small component of the wave vector in the axisdirection, in order the wave to rise through the electron-neutral collisions’proceedings, and iv) the stabilization of an azimouthal rotating instability by using anexternal electric signal (feed-back procedure).

0 5 10 15 20 25 30 350

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Fig. 4. (a) The plasma column cut is presented and (b) the cylinder outline at the external magneticfield.

Active Externally Funded research ProgramsMarie Curie TN Programme (FP7)“N.A.R.N.I.A.” (New Archaeological Research Network Integrating Approaches toAncient Materials Studies)2010-2014629,000.00 Euros. Project leader in charge: Y. Bassiakos

Conference OrganisationBassiakos, Y., Member of the Standing Commttee3rd International Conference ‘Archaeometallurgy in Europe29 June-1 July 2011 Deutsches Bergbau-Museum Bochum, Germany

Bassiakos, Y., Filippaki, E.History, Technology and Conservation of Ancient Metal, Glasses and Enamels,International Symposium16-19 November, 2011, Athens, Greece.

Conference ParticipationTheodorakopoulou, K., Athanassas, C.13th International Conference on Luminescence and Electron Spin Resonance DatingOptically Stimulated Luminescence dating of alluvial infills at a Roman necropolis in

NE Crete: the timeline of a riverbed diversion10-14 July 2011, Toruń, Poland.

Tzanis, C., Varotsos, C., Christodoulakis, J., Theodorakopoulou, K. InternationalSymposium on Kaz Mountains (Mount Ida) and Edremit -Global Change in theMediterranean RegionImpacts of the climate characteristics on materials; an overview of the ICP materialsactivities in Athens, GreeceMay 5-7, 2011, Edremit-Turkey.

Athanassas, C., Bassiakos, Y., Wagner, G.A., Timpson, M.15th Joint Geomorphological Metting


Exploring paleogeographic conditions at two paleolithic sites in Navarino, SWGreece, by means of Optically S timulated Luminescence dating..June 1-4, 2011, Athens.

Mastrotheodoros, G., Beltsios, K., Zacharias, N.5th International Conference on Emerging Technologies in Non-Destructive Testing,Iron based and other ancient pigments for pottery decoration19-21 September 2011, Ioannina, Greece

Mastrotheodoros, G., Beltsios, K., Zacharias, N. Arapogianni, X.History, technology and conservation of ancient metal, glasses and enamels,International SymposiumMycenaean glass and a study of Late Bronze Age Messenian glass artefacts” 16-19November 2011, Athens, Greece.

Filippaki E., Bassiakos, Y.3rd International Conference ‘Archaeometallurgy in EuropeArchaeo-metallurgical studies on iron production from the site of Priniatikos Pyrgos,Mirabello Gulf, Northeastern Crete29 June-1 July 2011 Deutsches Bergbau-Museum Bochum, Germany

Tselios, Ch, Filippaki E.3rd International Conference ‘Archaeometallurgy in Europe’Silver Plated Mycenaean Bronze Artifacts - Burial Offerings from the Tholos andChamber Tombs at the Region of Pylos in Peloponnese29 June-1 July 2011 Deutsches Bergbau-Museum Bochum, Germany

Bassiakos, Y, Michailidou. A.3rd International Conference ‘Archaeometallurgy in Europe’Metal Technology at Akrotiri on Thera: analytical studies on metallurgicalimplements and by-products29 June-1 July 2011 Deutsches Bergbau-Museum Bochum, Germany

Filippaki E., Xaplanteris C.L.4th Chaotic Modeling and Simulation International ConferenceCollision Frequency leads the Plasma in a Chaotic State. Influence on theConductivity31 May – 3 June 2011, Agios Nikolaos, Crete Greece

Filippaki E., Xaplanteris C.L.History, Technology and Conservation of Ancient Metal, Glasses and EnamelsEvaluation of three cleaning methods applied on Cl- rich artificial patinas of twobronzes16-19 November 2011, Athens, Greece.


Xaplanteris C.L., Filippaki E.The 7th International Conference on Instumental Methods of Analysis Modern Trendsand ApplicationsDesalination treatment by pure hydrogen plasma of Egyptian coin fragments fromTell Basta, evaluated by SEM/EDS and XRD18-22 Sept 2011, Chania, Crete Greece

Invited TalksTheodorakopoulou, K.‘Geoarchaeological studies in Crete’CEREGE, CNRS, international meeting on Mediterranean Geoarchaeology15-18 May 2011, Aix-en province, France

Teaching and Training ActivitiesBassiakos, Y., OrganiserTraining course “Luminescence and other dating techniques” funded by NARNIA-Marie Curie FP7-PEOPLE-ITN 2010-2014, NCSR “Demokritos”, IMS, 21-25 November2011

Athanassas, C., trainer, ‘Luminescence and cosmogenic nuclide dating techniques ingeology and archaeology’, Four lectures/t Training course “Luminescence and otherdating techniques” funded by NARNIA-Marie Curie FP7-PEOPLE-ITN 2010-2014,NCSR “Demokritos”, IMS, 21-25 November 2011

Filippaki E., trainer‘XDR analysis of datable inorganic materials’Training course “Luminescence and other dating techniques” funded by NARNIA-

Marie Curie FP7-PEOPLE-ITN 2010-2014,NCSR “Demokritos”, IMS, 21-25 November 2011

Filippaki E., trainer‘RF Plasma treatment of metallic archaeological objects’NCSR “Demokritos” Summer School, 4-15 July 2011

Athanassas, C., trainer‘Luminescence dating techniques’Four lectures/training classes given in the training course ‘Regional Training Courseon Advanced Utilization of Nuclear Techniques in Archaeology and material sciences’International Atomic Energy Agency, UN, Vienna, Austria. 3-14 October 2011

Athanassas, C., trainer‘Application of geochronological techniques in geoarchaeological research: The casesof Optically Stimulated Luminescence and in situ Cosmogenic Nuclides’.Seminar on Geology and Archaeological ResearchOrganized by the Univeristy of Athens, Chania Crete, 25-31 August 2011


Theodorakopoulou, K., trainer‘Landscape reconstruction by using dating and geomorphological techniques’Training course “Luminescence and other dating techniques” funded by NARNIA-Marie Curie FP7-PEOPLE-ITN 2010-2014,NCSR “Demokritos”, IMS, 21-25 November 2011

Doctoral Dissertations completed in 2011

Saleh Mohamed Saleh AhmedConservation methods of iron artifacts recovered from the marine environmentResearch Supervisor at NCSR “D”: Y. Bassiakos, also member of the PhD thesisExamining Committee, National Technical University of Athens, and School ofChemical Engineering


CERAMICS AND COMPOSITE MATERIALS

Research Director: Vassilis Kilikoglou

Permanent Research Staff: Anno Hein, Ioannis Karatasios

Contract Researchers: Anna Kalagri

Post-Doctoral Researchers: Noemi Muller

Visiting Researchers: Peter Day

PhD Candidates: Maria Tziotziou, Lenia Farmakalidou. Eirini AmpatzioglouMasters Students: Maria Amenta

External Collaborators: Dr. P.M. Day, University of Sheffield Dr. N. Maravelaki, Technical University of Crete Dr. D. Evely, The British School at Athens Dr. E. Kiriatzi and M. Georgakopoulou, Fitch Laboratory, The British School at

Athens Prof. V. Kassianidou, Dr M. Dikomitou, University of Cyprus Dr. M. Kiderlen, Winkelmann-Institut, Humboldt University at Berlin Prof. J. Maran, Institute of Prehistory and Early History, University of Heidelberg Prof. H. Mommsen, Helmholtz Institute for Nuclear Physics, University of Bonn.

Areas of Research: Provenance and Technology of archaeological and cultural materials Thermal properties and technological developments of ancient ceramics Mortars and grouts for the restoration of architectural monuments Setting and hydration process of lime-pozzolan mortars Weathering and consolidation of natural stones in architectural monuments Computer modelling for investigation of mechanical and thermal properties

Activities and Achievements:Thermal properties and heating efficiency of ancient pyrotechnical ceramics

One of the main foci of research in 2011 was the investigation of pyrotechnicalceramics in terms of their physicochemical composition and texture and in terms ofthe associated thermal properties. Pyrotechnical ceramics usually constitute a largepart of the archaeological evidence at sites with metallurgical activities. Ceramicmaterials have been used for smelting furnaces, but also for tools such as crucibles,moulds or tuyères. Technological studies of the pyrotechnical ceramics contribute to


the understanding of the metallurgical processes, to the evaluation of operationconditions and environmental constraints and to the assessment of the technologicallevel a specific society had reached.

One of the properties, affecting the ceramics’ performance most, is the thermalconductivity, which can be measured with a modified Lee’s disk set-up. Figure 1shows the results of measurements of fragments of Late Bronze Age (LBA) and EarlyBronze Age (EBA) copper smelting furnaces, applying the method for the first timeon archaeological samples.

Figure 1 – Thermal conductivity at c. 200°C and at c. 300°C of a series of fragments of Bronze Agecopper smelting furnaces

As expected the thermal conductivity increases with higher density as pores actas heat barriers and a higher porosity reduces the heat transfer. Apart from the totalporosity there are, however, also other parameters affecting the thermalconductivity, such as the pore structure or the mineralogical composition of theceramics.

The results of the measurements are used as input parameters for computersimulations, investigating the operation conditions of furnaces or crucibles. Thesimulations allow also for assessing the heating efficiency of pyrotechnicalinstallations or tools by estimating the heat loss into the environment. Only withappropriate heat efficiency it was possible to generate and maintain the sufficienttemperatures with reasonable use of fuel resources and man-power.

Mechanical properties of 16th century transport jars from Panamà and Seville

In the 16th century specialized potteryworkshops in Seville, Europe’s gate-wayto America, manufactured the largetransport jars destined for the commerceof goods with the new foundations inAmerica (Fig 1). In one of thesefoundations, Panamá in Central America,excavations have found Sevillan transportjars alongside locally produced red paste

Fig 1: 16th century trade routes and transportamphorae


transport jars, which appear to imitate European vessels.

High demands are placed on the mechanical performance of transport jars, whichare expected to keep contents safe during transport. Stresses arise due to weightloads, e.g. from overlying vessel layers, but also from collisions caused bymovements of the ship. In order to assess and compare the mechanical performanceof imported and locally produced transport vessels found at Panamá, their fracturestrength was tested and material parameters important for their mechanicalperformance, e.g. firing temperature and amount of aplastic inclusions weredetermined.

Sevillan vessels exhibit higher fracturestrength than locally produced Panamavessels. Differences in performance are dueto different manufacture technologiesemployed. Physico-chemical andmineralogical analyses confirmed that acalcareous base clay, tempered with riversand was employed in the manufacture ofSevillan transport jars. Jars were fired to hightemperatures, ensuring a well vitrifiedceramic body (Fig 2). Panamanian containerswere made from a non-calcareous base clayand, unlike Sevillian jars, do not appear to beintentionally tempered; naturally coarseclays were used in their manufacture. Firing temperatures appear lower and samplesshow less extensive vitrification. Locally produced and imported vessels havecomparable amounts of aplastic inclusions, but those in Panama samples arefrequently larger.

The use of calcareous clays and high firing temperatures in Sevillan manufactureresulted in a well vitrified ceramic microstructure, stable over relatively widetemperature range. This ensured a high strength product and the production of jarswith consistent quality. The use of non calcareous clays and lower firingtemperatures by artisans in Panama resulted in a material with lower strength levels.The loss in material quality seems to have been compensated with a significantincrease in wall-thickness, which ensured that albeit the use of less suitable rawmaterials and a not well adapted firing technology, locally produced vessels couldfulfil their function.

Technology and Conservation of Architectural MonumentsOne of the main activities of the Group is dedicated to the laboratory analysis andcharacterisation of archaeological and traditional mortars from architecturalmonuments with respect to the design of modern conservation mortars. The activityfocuses on the development of sustainable, eco-efficient conservation compositesthat involve the combination of traditional, low-cost earthen-based materials with

Fig 2: SEM micrographs and thin section photo-graphs (below, field of view 7mm, courtesy S.Ferrer) of Sevillan (left) and Panama jars (right).


modern, advanced and nano-materials, aiming to provide a variety of protective,strengthening, de-polluting and self-healing properties.Besides the communication of the knowledge produced by studying cultural heritagebuilding materials, into the specialised needs of modern materials used for theprotection of architectural heritage, the main working tasks include:

study of self-healing mechanism in ancient lime-based mortars andconditions to activate the phenomenon in modern structures.

enhancement of reactivity in natural and artificial, low-cost pozzolanicadmixtures.

Tailor-made design of conservation mortars for masonry applications andstrengthening of architectural monuments.

optimization of mortars properties in terms of strength and durabilityperformance towards the reduction of the production cost.

The deliverables/ achievements derived so far include: identification of self-healing mechanism in different case-studies of varying

periods and use of mortars, and of environmental parameters involved. Maximising of reactivity in clay based admixtures by thermal activation

bellow 500 oC and development of methodology for producing low-cost, eco-efficient pozzolans.

Development of material- and methodology- related solutions for existingconservation problems, directives for new products, along with enhancementof existing products for application in Cultural Heritage.

Development of hydrated setting phases aroundparticles of thermally activated clay-basedadmixtures, compared to the inert particles (insetpicture).

Filling of micro-cracks with secondary formed(precipitated) calcareous material.Micromorphology of the precipitated calciteparticles.

Chemical tool kit for in situ characterization of building materialsIn order to initiate protective countermeasures against irreversible damages of builtheritage it is important to understand the deterioration processes and developadequate methodology for evaluating in-situ and in an affordable manner thepreservation condition of historic and modern concrete structures. In the thiscontext, the main task of this activity is to develop an essential portable kit for the


in-situ qualitative and quantitative characterization of the most severe soluble salts(e.g Cl- and SO4

-2) as well as, the development of an easy to apply methodology forthe field surveys. This activity was conducted within the EU funded research project“DIAGNORAIL”.

The chemical kit developed incorporates simple tests, such as paper strips andmicrochemical kits for semi-quantitative determination of water soluble ions,together with portable instrumentation (i.e. UV-Vis Photometer and Ion SelectiveElectrodes). The kit was tested and calibrated in laboratory prepared test specimenswith known concentrations of chloride and sulphate salts, while additional effort wasmade in order to simplify the in-situ procedure and minimize the required amount ofmaterial sampled. The results obtained both in laboratory and field applications arein good agreement with traditional laboratory tests and therefore it is concludedthat the proposed chemical kit can be effectively used for routine monitoring ofpreservation condition and identification of risk factors in historic and modernconcrete structures.

The chemical kit developed, comprises a variety of easily applicable field-methodsfor the determination of water soluble ions, such as paper strips, colorimetrictitration, ion selective electrodes and a portable UV-Vis photometer.

Distribution profile of ions’ concentration determined on-site, in a segmentedconcrete tunnel.


Publications in International Refereed Journals

M. Tziotziou, E. Karakosta, I. Karatasios, G. Diamantopoulos, A. Sapalidis, M. Fardis,P. Maravelaki-Kalaitzaki, G. Papavassiliou, V. KilikoglouApplication of 1H NMR to hydration and porosity studies of lime-pozzolan mixturesMicroporous and Mesoporous Materials, 139, pp 16–24, 2011

Π. Μαραβελάκη, Α. Βεργανελάκη, Ι. Καρατάσιος, Β. ΚυλίκογλουΜέθοδος παρασκευής νανο-οξαλικού πυριτικού πηκτώματος με εφαρμογές σταδομικά υλικάΟΒΙ, Αρ. 1007392, 2011

Other Publications

Hein, A. and Kilikoglou, V.Chapter 18 - Technological aspects of Bronze Age metallurgical ceramics, Metallurgy:Understanding How, Learning whY: Studies in Honor of James D. Muhly (eds. P.P.Betancourt, S.C. Ferrence), INSTAP Academic Press, Philadelphia, 181-187, 2011.

GENERAL INFORMATION

INTRODUCTION

The mission of the IMS is to support high-quality interdisciplinary research and thepromotion of innovation in materials science and technology. The principal research aim isthe synthesis, preparation and study of the structure and physical properties of novelmagnetic, superconducting and semiconducting materials with emphasis on nanostructuredmaterials. In addition, there is a major complementary research activity in the field ofArchaeometry on the study of archaeological materials and the understanding of ancienttechnologies and their evolution.

The objectives of IMS implemented through the three main research programs cover:

Synthesis, characterization and theoretical study of the physical properties of new materialsfor product development and high-tech devices. Development of analytical techniques andmethods for the control of materials in order to provide specialized technical services andtechnology transfer to industry. Training of young scientists and technicians through post-graduate study programs and their participation in the research activities of the Institute.

The IMS has a large number of laboratory facilities unique in Greece, which enable aninterdisciplinary approach to research activities. New techniques are developed for thesynthesis of nanostructured materials (nanoparticles, thin films and nano-wires) forapplications based on their unique physical properties in a range of fields such as magneticrecording media, magnetic quantum dots, biological applications (dialysis, magnetichyperthermia ), sensors in low temperature semiconductor devices, catalysis, etc. Thussystematic investigations of the physical properties of these materials are carried out for thepurpose of understanding the underlying physical mechanisms to improve theireffectiveness and efficiency. Experimental techniques and computational physics methodsare used in conjunction for the refinement of theoretical models. Central to these activitiesare the Magnetic Thin Films and Nanostructured Materials laboratories (including the


Molecular Beam Epitaxy (MBE), Magnetron Sputtering, and Laser Ablation facilities) , SolidState Chemistry laboratories, Synthetic Chemistry and Liquid Chemistry nanostructuredmaterials laboratories, as well as the large number of characterization techniques such ascontinuous and pulsed Electron Paramagnetic Resonance (EPR), Nuclear MagneticResonance (NMR) covering the temperature range 2-1000 K, Mössbauer spectroscopy inmagnetic fields up to 7 Tesla, SQUID magnetometery, VSM and Hall sensor magnetometry(the sensitivity of the latter reaches 10-9 emu), powder and monocrystal X -raycrystallography, and the high precision Electron Microscopy SEM and TEM etc. The institutealso houses the unique facilities of the Laboratory of Archaeometry which, in combinationwith the IMS infrastructure, contributes significantly to the understanding and promotion ofthe country’s cultural heritage. Lastly, we must note the significant contribution that the IMSmakes to the needs of the wider society and industry in offering services such as non-destructive structural testing (Mobile Radiography unit), liquid Helium for use in medicalMRI units, as well as electron microscopy services, asbestos detection, and carbon- 14 datingamongst others.

The research activities of the IMS are grouped into three research programs and oneprogram dedicated to the provision of services. The research programs, as shown in theorganization chart, are:

- Magnetic and superconducting materials ( coordinator Dr. G. Papavassiliou).

- Electronic and composite materials (coordinator Dr. A. Travlos).

- Archaeometry (coordinator Dr. I. Maniatis).

The scientific activities of these programs are summarized as follows :

(I ) Magnetic and Superconducting materials

The aim of this program is to conduct basic and applied research on materials of hightechnological interest in the following areas :

• Hard magnetic materials.

• Magnetic recording media.

• Magnetic nanoparticles , nano-wires , quantum dots.

• Nanoparticles for biological applications (hemodialysis, hyperthermia).

• Left-handed magnetic materials.

• High Temperature Superconducting (HTS) materials and colossal magnetoresistance.

• Heavy fermion systems.

• Hybrid nanostructured materials.

• Molecular magnetic materials.

• Biomolecular magnetic systems.


• Computational condensed matter physics.

• Theoretical many-electron and magnetic systems.

(II ) Electronic and Composite Materials

The activities in this program cover the following areas :

• High dielectric and semiconductor materials for nanoelectronic devices

• Metal- semiconductor Si nanoparticles

• Large energy gap semiconductor nanostructures.

• Conductive polymer coatings and ORMOSIL inhibitors deposited on self-healing metals.

• Nano-containers for drug delivery.

• Antibacterial nano-containers.

• Heat-protection systems for space and satellite applications.

• Advanced ceramic composites with improved mechanical properties.

• Inorganic catalytic materials for chemical and environmental applications.

( III ) Archaeometry

The research areas in the field of Archaeometry focus on the following areas:

• High precision radiocarbon dating, luminescence and ESR.

• Technology and origin of ceramic and glassy materials.

• Origin and distribution of stone materials (marble, obsidian, steatite ).

• Archaeometallurgy and ancient metals.

• Geo-archeology and the palaeo-environment.

• Nutrition and organic residues.

• Erosion mechanisms, repair and stabilization of artifacts and monuments.

• Development of restorative materials for antiques and monuments.

Active Externally Funded research Programs

The Institute for Aegean Prehistory“Thermal efficiency of metallurgical ceramics in Bronze Age – Assessment of materialproperties and operation conditions”, January 1st-December 31st 2011, 7000 US$


Greek Secretariat of Research, SYNERGASIA“NANO-COMPOSITE BIO-INSPIRED MATERIALS FOR THE CONSOLIDATION OFBUILDING MATERIALS “NANOBIODOMIL”, 2011-2013, € 90,000

EE FP7“Combining innovative portable visual, acoustic, magnetic, and nmr methods, within-situ chemical diagnostic tools for effective failure assessment and maintenancestrategy of rail and subway systems – DIAGNORAIL”, 2011-2013, € 110,000

EE Marie Curie Initial Training Networks (ITN), FP7-PEOPLE-2010-ITN“New Archaeological Research Network for Investigation Approaches to ancientmaterials studies” 2010-2014

Conference ParticipationHein, A., Karatasios, I., Müller, N.S., and Kilikoglou, V.Archaeometallurgy in Europe 3Material properties of pyrotechnical ceramics used in the Bronze Age Aegean andimplications on metallurgical technologies,June 29th-July 1st 2011, Bochum.

Michael C.T. and Hein, A.8th International Topical Meeting on Industrial Radiation and RadioisotopeMeasurement Application High sensitivity measurements by using thick source alphaspectroscopyJune 26th – July 1st 2001, Kansas City.

Hein, A., Kilikoglou, V., and Mommsen H.,11th European Meeting on Ancient CeramicsOne step beyond – ‘Mycenaean’ pottery production in Central Greece,September 29th – October 1st 2011, Vienna.

Georgopoulou, V., Hein, A., and Kilikoglou, V.11th European Meeting on Ancient CeramicsThe double barreled handle of the East Aegean transport amphora – Stylistictrademark or functional innovationSeptember 29th – October 1st 2011, Vienna.

Karatasios, I., Hein, A., Kilikoglou V., and Triantaphylidis, P.11th European Meeting on Ancient CeramicsTechnological study of Hellenistic ceramic beehives found at Tragaia island(Agathonisi), Greece,September 29th – October 1st 2011, Vienna.

Mourelatos, D. and Hein, A.History, Technology and Conservation of Ancient Metal, Glasses and EnamelsEarly Byzantine Metal Workshops in a settlement near Saint Catherine’s Monastery(Mount Sinai, Egypt),


November 16th-19th 2011, Athens.Müller, N.S., Kilikoglou, V., and Day, P.M.Food economy & diet during the Bronze Age in EuropeCooking at Bronze Age Akrotiri: cooking vessles, material properties and cookingmethodsNovember 8th-9th 2011, Aix-en-Provence, France

Müller, N.S., Gomez Ferrer, S., Buxeda i Garrrigós, J., and Kilikoglou, V.11th European Meeting on Ancient CeramicsPost-depositional alteration effects on the structural integrity of archaeologicalceramicsSeptember 29th – October 1st 2011, Vienna, Austria

Day. P.M., Müller, N.S., Gilstrap, W., Kilikoglou, V., Papadimitriou, A., Marabea, C.,and Yannos, G.11th European Meeting on Ancient CeramicsFineware and beyond: Production and exchange of pottery from the Mycenaean portof Kanakia, SalamisSeptember 29th – October 1st 2011, Vienna, Austria

Alexiou, K., Karatasios, I., Müller, N.S., and Kilikoglou, V.,11th European Meeting on Ancient CeramicsThe performance of different adhesives for archaeological ceramics undermechanical stressSeptember 29th – October 1st 2011, Vienna, Austria

Invited TalksHein, A.Materials Science in the Interpretation of the Archaeological RecordSTARC house seminarNovember 22nd 2011, The Cyprus Institute, Nicosia.

Teaching and Training ActivitiesHein, A.“Demokritos” Summer School for Post-graduate students, 4th-15th July 2011, 1 hourlectureN.C.S.R. “Demokritos”

Hein, A., Mueller, N., Kilikoglou, V., Karatasios. I.NARNIA Workshop - Physical and chemical properties of clays and archaeologicalceramics, October 17th–21st 2011, Marie Curie FP7-PEOPLE-ITNN.C.S.R. “Demokritos”

Hein, A.NARNIA Workshop - Luminescence and other dating techniques, November 21st-25th

2011, 2-hour lecture, Marie Curie FP7-PEOPLE-ITNN.C.S.R. “Demokritos”


Noémi S. MuellerThermal and mechanical properties of ancient ceramics, July 2011, 1h Lecture(Summer School at Demokritos)Athens, NCSR Demokritos

Vassilis KilikoglouTechnology of Archaeological Materials, MSc in Museum Studies, University ofAthensArchaeometry, Ceramic Materials, MSc in Restoration of Monuments, University ofThessaloniki.

Research ConsultationI. KaratasiosTask Leader on Work item 4: Characterization of Stone and related buildingmaterials,CEN TC 346/ WG 2: Conservation of Cultural Property/ Materialsconstituting cultural property

V. Kilikoglou, I. KaratasiosTechnical Committee of ELOT, ΤΕ 96 «Conservation of Cultural Heritage»

V. KilikoglouCommittee Member on Work item 4: Characterization of Stone and related buildingmaterials,CEN TC 346/ WG 2: Conservation of Cultural Property/ Materialsconstituting cultural property


STABLE ISOTOPE UNIT

Scientific Supervisor : Dotsika E.

PhD CANDIDATES : Zisi N., Kyropoulou D., Bakas M.

MSc CANDIDATES : Papaharalampou Ch.

UNDERGRADUATE STUDENTS : Karabournioti M. Chiotis S.

TECHNICIANS : Karalis P.

EXTERNAL COLLABORATORSLonginelli A., Colonese A, Raco B., Zanchetta G., Ghilardi M., Kloppmann W.,Christars V., Albanakis K., Tsoukala E., Lykoudis S.

ACTIVITIES AND ACHIEVEMENTS 2011a) Material and Environmental Isotope Geochemistry (Initiator and Coordinator ofthe Material and Environmental Isotope Geochemistry Program and of Stable IsotopeUnit of the Institute of Material Science, National Centre for Scientific Research"Demokritos").Principal aim of Material and Environmental Isotope Geochemistry is to conductbasic and applied research in the scientific field of Isotopic Geochemistry, focusingon material science, environmental evolution and cultural heritage. In specific, theresearch is centered in the following scientific areas:1. Development of novel and combined methodologies for the determination of

stable isotope composition of different materials: geological, biological,composite and natural.

2. Provenance of archaeological materials and origin of raw materials.3. Characterization and investigation of the technology of ancient–historic

structural materials (marbles, glass and mortars).4. Damage diagnosis and decay mechanisms of ancient-historic materials and

development of conservation materials.5. Authenticity and fingerprinting of food and products.6. Paleoenvironmental and paleoclimatic reconstruction.7. Hydrogeochemical processes in open and closed systems.8. Origin of geofluids, pollution, hydrology, palaeohydrology.

b) Analytical WorkThe Stable Isotope Unit (SIU) of the Institute of Material Science is accreditedaccording to EN ISO/IEC 17025:2005 (No 579). In SIU, the isotopic measurementsinclude the stable isotopes of inorganic materials (stones, rock, glass, bones, teeth)(δ13C, δ18Ο), organic materials (δ13C, δ15Ν), water (water, juices, wine…) (δ18Ο, δ2Η),


sulfates (δ34S) as well as elemental analysis of C, N and S in geological, biological,composite and natural materials.

1. Investigation of Early vitreous Technology Construction Materials and Glass.Investigate raw material of glasses manufacturing technology with heating. Thearchaeological glasses are from Roman Byzantine and Ottoman period.In 2011 research was continued on δ18Ο and chemical measurements of Roman glassfrom Greece

ObjectivesArchaeologists argued that in Greek antiquity glass was not made but the vitreousmaterial was imported from different areas of the East Mediterranean coast.Especially in the Greco-Roman age, glass artefacts in Greece are considered to havebeen manufactured using raw glass made with sand and natron, and produced inEgyptian and Near East glass-making factories. These factories probably producedonly batches of raw glass and not necessarily vessels or other objects. Theimportation of raw glass complicates more the existing problem regarding theidentification of the origin of the basic components of glass and the fusion processes.Thus, it is of utmost importance to distinguish the origin and composition of ‘Roman’age glasses from glasses imported from other provenances. In this study chemicaland isotopic methods, were employed for the identification of the fingerprint ofRoman glasses manufactured in Greece, for distinguishing the different rawmaterials and fluxes used and for defining the production technology.

2. Research to Identify Natron in Greece.In 2011 research was continued on the Isotope contents, Cl/Br ratio and origin ofwater at Pikrolimni Lake: a natron source in ancient Greece, as archive of pastenvironmental conditions.

ObjectivesThe origin of Pikrolimni water was investigated in this study, using stable isotopes, toconfirm Pliny’s description that “chalastraion nitron” was produced in the basin ofLake Pikrolimni (Northern Greece). Lake Pikrolimni is located in the basin of Kilkisplain, northern Greece, formed in a shallow depression. Lake Pikrolimni is not fed byany major river, and the hydrography of the area shows that no perennial streamsenter the lake directly. In the past, the major source of water to the lake was groundwater. Today the dominant inflow to Lake Pikrolimni is meteoric water. The meteoricorigin of the water is one of the necessary geochemical conditions that areindispensable and responsible for the formation of carbonate bicarbonate sodium(Natron, Trona) minerals.

3. Palaeo-Environment ReconstructionInvestigate water systems sediment deposition and erosion in caves, tombs andother environments that can provide information for dating, origin as well asevolution and recovery of palaeoenvironment and palaioecology. The concentrationof 13C and 18O in materials such as bones, spilaiothems, carbonate sediments, etc.,


which varies depending on climatic changes, can supply also information forpalaeoenvironment reconstruction.a) BONES. During the last four decades, the analysis of stable isotopes in terrestrialteeth and bones has provided valuable information about the palaeoclimatic andpalaeoenvironmental conditions on the Quaternary period as well as palaeodiethabits for a variety of species. Oxygen and carbon comprise principal structuralmaterials of skeleton and teeth. These elements mainly originate from the water andfood that the animal consumes, and reflect the respective isotopic fingerprints oftheir original sources. In 2011 research was conducted on palaeo-climaticinformation from isotopic signatures of Late Pleistocene Ursus ingressus bone andteeth apatite (Loutra Arideas Cave, Macedonia, Greece). Bones and teeth samples ofUrsus ingressus from Loutra Arideas Cave (Greece) were used to determine the dietof this extinct species and to reconstruct the palaeoclimatic conditions. Severalpossible effects that may affect the isotopic composition of apatite wereinvestigated, including age, sex, tooth type and diagenesis.

B) SEDIMENTS. In 2011 research was continued on the impact of rapid early- to mid-Holocene palaeoenvironmental changes on Neolithic settlement at Nea Nikomideia,Thessaloniki Plain, Greece.The site of Nea Nikomideia is one of the oldest and most important Neolithicsettlements in Northern Greece and the wider Balkan Peninsula, having been firstoccupied by early farmers at around 6500 cal. BC. Important archaeologicalexcavations conducted in the 1960s suggested that the settlement was located closeto an ancient coastline during the Neolithic. However, palaeoenvironmental changeand landscape evolution in the vicinity of the site have seldom been considered indetail. Six cores from the western and central parts of the Thessaloniki Plain weretherefore drilled in 2008 and subjected to palaeoenvironmental analyses, includingsedimentology (LASER grain size and magnetic susceptibility measurements),chemical analysis (loss on ignition and carbonate content), stable isotopes analysiscoupled with X-Ray diffraction measurements, molluscan faunal analysis andradiocarbon dating. The recognition of several important faces representingfreshwater (lacustrine and fluvial) and brackish (lagoonal and marine-influenced)conditions have shed light on the environmental and landscape evolution of thewestern part of the Thessaloniki Plain and associated impacts on human occupationduring the last 10,000 years.

4. MortarMortar samples from historic masonries dated from Hellenistic to Ottoman periodwere examined using stable isotope analysis. The study will focus on the analysis ofstable isotopes of oxygen and carbon (13C and 18O), to determine the origin of calciteand to diagnose the state of preservation of historic mortars.Conducted as part of a doctoral thesis (Kyropoulou D.).

ObjectivesSamples of mortars were collected from historic constructions and wall-paintingsdating from Hellenistic to Ottoman period. The main aims of this researchprogramme are to investigate the technological transition of historic mortars from


Hellenistic to Ottoman period and to examine the potential sources of materialdegradation. To achieve the aims of the project the samples will be analysed usingtraditional techniques of instrumental analysis such as X-ray diffraction and scanningelectron microscopy with X-ray microanalysis. Parallel to this, stable isotope analysis(13C and 18O) will be performed in order to obtain further knowledge on thetechnology, provenance and degradation of historic mortars. The signs of materialdecay are expected to be reported in isotopic values and therefore determine thesources of mortar’s degradation.

5. Modern Environment - PollutionThe use of stable isotopes (13C, 18O, 34S, 18O(SO4), 18O(CO2), 2H, 18O(H2O), 11B, 87Sr/86Sr)allows the study of aquatic environment (the source of dissolved carbonate, sourceof water, source of data, mixing), the deep geothermal fluids (water source, sourceof elements, water-rock interaction, geothermometry) of geological materials (originof carbonate rocks, travertine, etc.), of the atmosphere (the source of infectionthrough the study of CO2 and CO and control of human intervention in thesurrounding cities or industrial zones).Conducted in cooperation with Dr. Raco B., CNR Pisa (Italy) and Dr. Kloppmann W,BRGM, Service EAU (France).

In 2011 research was continued on the distribution and origin of boron in fresh andthermal waters in different areas of Greek world.

ObjectivesOrganization (WHO) guideline value for boron is 0.5 mg/l. The drinking-waterstandard of the European Community (EC Directive, 1983) is twice the valuerecommended by WHO, but still boron concentrations in many ground- and surfacewaters in Greece exceed this value, rendering such water unacceptable according tothe European standards. Boron is biologically an essential element, but at highconcentrations is toxic to plants (above approximately 1 mg/l in irrigation water) andprobably to humans. Because of this potential toxicity and the need ofimplementation of EU regulation on national level, the study of the boron levels inboth ground- and surface water is of great significance for water management. InGreece, a significant number of thermal, mineral and superficial water springs,especially in Northern Greece and in islands, present high boron values.Nevertheless, such ground waters or borehole water with high temperature and highboron content are frequently used for irrigation and drinking purposes, and couldtherefore have an antagonistic effect on crop yield and health. In order to study theboron contamination and to elucidate the origin of B, we collected a number of hotand fresh waters all over Greece.

Active Externally Funded research Programs1. 12th Ephoreia of Byzantine Antiquities, Kavala, Greece “Conservation,

consolidation-restoration of antiquities in the region of Eastern Macedonia andThrace (Anaktoroupoli of Nea Peramos, land walls in Kavala, fortification walls in


Drama, Byzantine tower in Amfipoli, wall paintings in the catholic of the HolyMonastery of Timios Prodromos in Serres)”, 2011-2012, 23.100€.

2. General Secretariat for Research and Technology and Alpha Estate SA,“Development of isotopic indices for the traceablity-authenticity of wineproducts and application of innovative methodology for the management ofwining vineyard in Protected Designation of Origin (PDO) Amyndeon”, 2011-2014, 156.000€.

Conference Participation1) Scoccari A.Conference Title “The NATO Science for peace and Security Programme.Environmental Security, Management and Control”Presentation: Distribution and origin of Boron contents in fresh and thermal water indifferent areas of Greece.Conference dates, location: 9/2011, Marrakech, Maroc.

2) EGU European Geosciences UnionConference Title “Energy, Resources and the Environment”Presentation: Pollution and Geochemistry.Conference dates, location: 5/2011, Vienna, Austria.

3) Conference Title “Fifteenth International Water Technology Conference”Presentation: Distribution and origin of Boron contents in fresh and thermal water indifferent areas of Greece.Conference dates, location: 6/2011, Cairo, Egypt.

4) IWTJConference Title International Symposium on “History, Technology and Conservationof Ancient Metal, Glasses and Enamels”Presentation: δ18Ο and chemical measurements of Greek Roman glass.Conference dates, location: 7/2011, Athens.

Invited TalksRaco B., C.N.R., Institute of Geosciences and Earth Resources Pisa, ItalyTitle of Talk Isotope GeochemistryConference TitleConference dates, location: 5/2011, Pisa, Italy.

Teaching and Training ActivitiesName: Dotsika E.Activity Title, Dates/Duration of lectures/training: Isotope HydrogeochemistryLocation/Academic Institute: Department of Geology, Aristotle Univ. of Thessaloniki.

Doctoral Dissertations completed in 20111) Name: Psomiadis DavidDissertation Title: “Palaioenvironmental and sedimental conditions for the formationof beachrocks in North Aegean)”


Research Supervisor at NCSR: Dr. Dotsika E.University where the Thesis was presented: Department of Geology, Aristotle Univ.of Thessaloniki.

2) Name: Menichini MatiaDissertation Title: “A multidisciplinary approach to define the hydrogeological modelof aquifer systems in the "Fiume Versilia" catchment and the adjacent coastal plain(Northwest Tuscany, Italy)”Research Supervisor at NCSR : Dr. Dotsika E.University where the Thesis was presented: Department of Geology, Università degliStudi di Pisa, Italy.

3) Name: Sumbele Sally AllohDissertation Title: “Photosynthetic characteristics of representative plant species ofthe Mediterranean Ecosystem”Research Supervisor at NCSR : Dr. Dotsika E.University where the Thesis was presented: Agricultural University of Athens,Department of Biotechnology, Faculty of Plant Biology.


LABORATORY OF ARCHAEOMETRY

Research Director: Y. ManiatisPermanent Research Staff: Y. Bassiakos, A. Hein, V. Kilikoglou, Ch.

MichaelScientific Personnel: E. Filippaki , I. KaratassiosTechnical Personnel: M.E. Kyriazi

Activities:The use of techniques and methodologies emanating from the research activities, inorder to provide routine services to third parties for archaeological objects,monuments, works of art and materials.The demand for such services is high and usually comes from various scientificorganizations, commercial firms, local authorities and societies and privateindividuals in Greece and abroad. These can be Universities, Technical Institutions,the Archaeological Service of Greece, Archaeological institutes, foreignarchaeological schools, Municipalities, Cultural societies, Monasteries, antiquedealers and antique collectors.

Some of the types of services offered in 2011 regarded: Dating with Radiocarbon1 and Luminescence of a wide range of organic and

inorganic materials Characterization of various materials, such as, fossils, aggregates, paleosoils,

archeological layers, house walls, vessel contents, metals, coins, etc. Characterization of pigments on marble, wall paintings, icons and canvals

paintings, plasters, etc. Provenance determination of marble from monuments and works of art from

Museums and collections in Greece and abroad. Ancient mortar analysis and characterization.

1 The Radiocarbon Unit is fully conforming with the specifications of EN-45001


1. Mitsionis, A., Vaimakis, T., Trapalis, C., Todorova, N., Bahnemann, D., Dillert, R.Hydroxyapatite/titanium dioxide nanocomposites for controlled photocatalyticNOOxidation(2011) Applied Catalysis B: Environmental, 106, pp. 398– 404.

2. Pomoni, K., Vomvas, A., Todorova, N., Giannakopoulou, T., Mergia, K., Trapalis, C.Thermal treatment effect on structure, electrical conductivity and transientphotoconductivity behavior of thiourea modified TiO2 sol–gel thin films(2011) J. Alloys and Compounds, 509 (26), pp.7253-7258,

3. Bourlinos, A.B., Karakassides, M.A., Stathi, P., Deligiannakis, Y., Zboril, R., Dallas,P., Steriotis, T.A., Stubos, A.K., Trapalis, C.Pyrolytic formation of a carbonaceous solid for heavy metal adsorption(2011) J Mater Sci 46, pp.975–982.

4. Herchel, R., Tucek, J., Travnicek, Z., Petridis, D., Zboril, R.Crystal Water Molecules as Magnetic Tuners in Molecular MetamagnetsExhibiting Antiferro-Ferro-Paramagnetic Transitions(2011) Inorganic Chemistry, 50, (18), pp. 9153-9163

5. G. Papavassiliou, D. Argyriou, N. Panopoulos, D. Koumoulis, N. Boukos, M. Fardis,M. Pissas, Hae Jin Kim, Jin-Gyu Kim, Seung Jo YooMHz Broadline NMR and HRTEM in the Study of Novel Strongly CorrelatedElectron Materials,Journal of Analytical Science & Technology (2011) 2 (Suppl A), A31-A37.

6. Molle A, S. Baldovino, M. Fanciulli, D. Tsoutsou, E. Golias, A. DimoulasImpact of post deposition annealing in the electrically active traps at the interfacebetween Ge(001) substrates and LaGeOx films grown by molecular beamdepositionJ. Appl. Phys. 110, 084504 (2011)

7. F. Boscherini, F. D'Acapito, SF Galata, D. Tsoutsou, A. DimoulasAtomic scale mechanism for the Ge-induced stabilization of the tetragonal, veryhigh-kappa, phase of ZrO2Appl. Phys. Lett. 99, 121909 (2011)

8. Golias, D., L. Tsetseris, A. DimoulasGe-related impurities in high-k oxides: Carrier traps and interaction with nativedefectsMicroel. Eng. 88, 1432 (2011)

PUBLICATION LIST


9. Tsoutsou, D., Y. Panayiotatos, S. Galata, A. Sotiropoulos, G. Mavrou, E. Golias, A.DimoulasThe effect of Se and Se/Al passivation on the oxidation of GeMicroel. Eng. 88, 407 (2011)

10. Golias D., L. Tsetseris, A. Dimoulas, ST PantelidesGe volatilization products in high-k gate dielectricsMicroel. Eng. 88, 427 (2011)

11. V. Ioannou-Sougleridis, SF Galata, T. Speliotis, A. Dimoulas, D. Giubertoni, S.Gennaro, M. BarozziHigh performance n(+)/p and p(+)/n germanium diodes at low-temperatureactivation annealingMicroel. Eng. 88, 254 (2011)

12. MS Rahman, EK. Evangelou, A. Dimoulas, G. Mavrou, S. GalataCurrent instabilities in rare-earth oxides-HfO(2) gate stacks grown on germaniumbased metal-oxide-semiconductor devices due to Maxwell-Wagner instabilitiesand dielectrics relaxationJ. Vac. Sci. Technol. B 29 01AB06 (2011)

13. Xanthopoulou G.Some Advanced Applications of SHS: An Overview, International Journal of SelfPropagating High-Temperature Synthesis, no.4, v.20, 2011, pp 269-272.

14. Chrysina M., Zahariou G., Sanakis Y., Ioannidis N., Petrouleas V.Conformational changes of the S2YZ intermediate of the S2 to S3 transition inphotosystem IIJournal of Photochemistry and Photobiology B: Biology, 104 (1-2), pp. 72-79,2011

15. Casitas, A., Ioannidis, N., Mitrikas, G., Costas, M., Ribas, X.Aryl-O reductive elimination from reaction of well-defined aryl-Cu III species withphenolates: The importance of ligand reactivityDalton Transactions, 40 (35), pp. 8796-8799, 2011

16. Zueva, E.M., Sameera, W.M.C., Pinero, D.M., Chakraborty, I., Devlin, E., Baran, P.,Lebruskova, K., Sanakis, Y., McGrady, J.E., Raptis, R.G.Experimental and Theoretical Mössbauer Study of an Extended Family of [Fe8(μ4-4-R-pz)12Χ4] ClustersInorganic Chemistry, 50, pp. 1021-1029, 2011

17. Georgopoulou, A. N., Sanakis, Y., Boudalis A.K.Magnetic Relaxation in basic iron(III) carboxylate [Fe3O(O2CPh)6(H2O)3]ClO4·pyDalton Trans, 40, pp. 6371-6374, 2011


18. Masello, A., Sanakis, Y., Boudalis, A,K., Abooud, K.A., Christou, G.Iron(III) Chemistry with Ferrocene-1,10-dicarboxylic Acid (fdcH2): An Fe7 Clusterwith an Oxidized fdc- LigandInorganic Chemistry, 50, pp. 5646-5645, 2011

19. E. G. Moshopoulou, O. Isnard, M. Milanovic, V. V. SrdicProbing the Transition from Nano- to Bulk-Like Behavior in ZnFe2O4NanoparticlesMaterials Science Forum 674, pp. 207-214 2011.

20. Ferentinos, E., Maganas, D., Raptopoulou, C.P., Terzis, A., Psycharis, V.,Robertson, N., Kyritsis P.Conversion of tetrahedral to octahedral structures upon solvent coordination:studies on the M[(OPPh2)(SePPh)2N]2 (M = Co, Ni) and[Ni{(OPPh2)(EPPh2)N}2(dmf)2] (E = S, Se) complexesDalton Transactions, 40, pp. 169-180, 2011

21. Skyrianou, K.C., Psycharis, V., Raptopoulou, C.P., Kessissoglou, D.P., Psomas, G.,Nickel-quinolones interaction. Part 4 – Structure and biological evaluation ofnickel(II)-enrofloxacin complexes compared to zinc(II) analoguesJournal of Inorganic Biochemistry, 105, pp. 105, 63-74, 2011

22. Katsoulakou, E., Konidaris, K.F., Terzis, A., Raptopoulou, C.P., Perlepes, S.P.,Manessi-Zoupa, E., Kostakis, G.E.One-dimensional cadmium(II)/bicinate(-1) complexes: The role of the alkali metalion used in the reaction mediumPolyhedron, 30, pp. 397-404, 2011

23. Sagnou, M., Benaki, D., Triantis, Ch., Tsotakos, Th., Psycharis, V., Raptopoulou,C.P., Pirmettis, I., Papadopoulos, M., Pelecanou, M.Curcumin as the OO bidentate ligand in "2+1" complexes with the [M(CO)3]+ (M =Re, 99mTc) tricarbonyl core for radiodiagnostic applications Inorganic Chemistry,50, pp. 1295-1303, 2011

24. Menelaou, M., Daskalakis, M., Mateescu, A., Raptopoulou, C.P., Terzis, A.,Mateescu, C., Tangoulis, V., Jakusch, T., Kiss, T., Salifoglou, A.In depth investigation of the synthesis, structural, and spectroscopiccharacterization of a high pH binary Co(II)-N,N-bis-(phosphonomethyl)glycinespecies. Association with aqueous speciation studies of binary Co(II)-(carboxy)phosphonate systemsPolyhedron, 30, pp. 427-437, 2011

25. Stamatatos, Th.C., Perlepes, S.P., Raptopoulou, C.P., Psycharis, V., Klouras, N.Reactions of the metallocene dichlorides [M(Cp)2Cl2] (M = Zr, Hf) and[Ti(MeCp)2Cl2] with the pyridine-2,6-dicarboxylate(-2) ligand: Synthesis,spectroscopic characterization and X-ray structures of the productsPolyhedron, 30, pp. 451-457, 2011


26. Gabriel, C., Raptopoulou, C.P., Psycharis, V., Terzis, A., Zervou, M., Mateescu, C.,Salifoglou, A.1D-3D Metal-Organic lattice assemblies through chemical reactivity and metal-assisted ligand transformations in ternary Pb(II)-phenanthroline-(hydroxyl)dicarboxylic acid systemsCrystal Growth & Design, 11, pp. 382-395, 2011

27. Lazarou, K.N., Psycharis, V., Terzis, A., Raptopoulou, C.P.Network diversity and supramolecular isomerism in copper(II)/1,2-bis(4-pyridyl)ethane coordination polymersPolyhedron, 30, pp. 963-970, 2011

28. Lazarou, K.N., Boudalis, A.K., Psycharis, V., Raptopoulou, C.P.Copper(II)-mediated oxime-nitrile coupling in non-aqueous solutions: Synthetic,structural and magnetic studies of the copper(II)-salicylaldehyde oxime reactionsystem, Inorganica Chimica Acta, 370, pp. 50-58, 2011

29. Kyprianidou, P., Tsoukalas, Ch., Chiotellis, A., Papagiannopoulou, D.,Raptopoulou, C.P., Terzis, A., Pelecanou, M., Papadopoulos, M., Piormettis, I.First example of well-characterized Re and 99mTc tricarbonyl complexes ofciprofloxacin and norfloxacin in the development of infection-specific imagingagentsInorganica Chimica Acta, 370, pp. 236-242, 2011

30. Boulsourani, Z., Geromichalos, G.D., Repana, K., Yiannaki, E., Psycharis, V.,Raptopoulou, C.P., Hadjipavlou-Litina, D., Pontiki, E., Dendrinou-Samara, C.Preparation and pharmacochemical evaluation of mixed ligand copper(II)complexes with triethanolamine and thiophenyl-2 saturated carboxylic acidsJournal of Inorganic Biochemistry, 105, pp. 839-849, 2011

31. Katsoulakou, E., Bekiari, V., Raptopoulou, C.P., Terzis, A., Manessi-Zoupa, E.,Powell, A., Perlepes, S.P.Simultaneous coordination of a ketone by two cadmium(II) ions and conversion toits gem-diolate(-1) formInorganic Chemistry Communications, 14, pp. 1057-1060, 2011

32. Chrysomallidou, K.E., Perlepes, S.P., Terzis, A., Raptopoulou, C.P.Preparation, characterization and biological relevance ofcalcium(II)/diethylmalonate(-1,-2) complexesInorganica Chimica Acta, 373, pp. 262-265, 2011

33. Georgopoulou, A.N., Adam, R., Raptopoulou, C.P., Psycharis, V., Ballesteros, R.,Abarca, B., Boudalis, A.K.Expanding the 3d-4f heterometallic chemistry of the (py)2CO and pyCOpyCOpyligands: structural, magnetic and Mössbauer spectroscopic studies of two FeII-GdIII complexesDalton Transactions, 40, pp. 8199-8205, 2011


34. Dimiza, F., Fountoulaki, S., Papadopoulos, A.N., Kontogiorgis, C.A., Tangoulis, V.,Raptopoulou, C.P., Psycharis, V., Terzis, A., Kessissoglou, D.P., Psomas, G.Non-steroidal anti-inflammatory drug-copper(II) complexes: Structure andbiological perspectivesDalton Transactions, 40, pp. 8555-8568, 2011

35. Boulsourani, Z., Tangoulis, V., Raptopoulou, C.P., Psycharis, V., Dendrinou-Samara, C.Ferromagnetic and antiferromagnetic copper(II) complexes: Counterplay betweenzero-field effects of the quartet ground state and intermolecular interactionsDalton Transactions, 40, pp. 7946-7956, 2011

36. Konidaris, K.F., Bekiari, V., Katsoulakou, E., Raptopoulou, C.P., Psycharis, V.,Perlepes, S.P., Stamatatos, T.C., Manessi-Zoupa, E.Initial employment of pyridine-2-amidoxime in zinc(II) chemistry: Synthetic,structural and spectroscopic studies of mononuclear and dinuclear complexesInorganica Chimica Acta, 376, pp. 470-478, 2011

37. Stamatatos, Th.C., Raptopoulou, C.P., Perlepes, S.P., Boudalis, A.K.The first non-acetato members of the bis(anion)octacarboxylatotetrakis{di-2-pyridyl-methanediolate(_2)}enneametal(II) family of complexes: Synthesis, X-raystructures and magnetism of [M9(N3)2(O2CCMe3)8{(py)2CO2}4] (M = Co, Ni)Polyhedron, 30, pp. 3026-3033, 2011

38. Papagiannopoulou, D., Tsoukalas, Ch., Makris, G., Raptopoulou, C.P., Psycharis,V., Leondiadis, L., Gniazdowska, E., Koźmiński, P., Fuks, L., Pelecanou, M.,Pirmettis, I., Papadopoulos, M.S.Histidine derivatives as tridentate chelators for the fac-[MI(CO)3] (Re, 99mTc, 188Re)core: Synthesis, structural characterization, radiochemistry and stabilityInorganica Chimica Acta, 378, pp. 333-337, 2011

39. Georgopoulou, A.N., Efthymiou, C.G., Papatriantafyllopoulou, C., Psycharis, V.,Raptopoulou, C.P., Manos, M., Tasiopoulos, A.J., Escuer, A., Perlepes, S.P.Triangular NiII2LnIII and NiII2YIII complexes derived from di-2-pyridyl ketone:Synthesis, structures and magnetic propertiesPolyhedron, 30, pp. 2978-2986, 2011

40. Alexandropoulos, D.I., Mukherjee, S., Papatriantafyllopoulou, C., Raptopoulou,C.P., Psycharis, V., Bekiari, V., Christou, G., Stamatatos, Th.C.A new family of nonanuclear lanthanide clusters displaying magnetic and opticalpropertiesInorganic Chemistry, 50, pp. 11276-11278, 2011


41. Kaliva, M., Gabriel, C., Raptopoulou, C.P., Terzis, A., Voyiatzis, G., Zeervou, M.,Mateescu, C., Salifoglou, A.A unique dinuclear mixed V(V) oxo-peroxo complex in the structural speciation ofthe ternary V(V)-peroxo-citrate system. Potential mechanistic and structuralinsight into the aqueous synthetic chemistry of dinuclear V(V)-citrate species withH2O2

Inorganic Chemistry, 50, pp. 11423-11436, 2011

42. Tsotakos, T., Tsoukalas, C., Patsis, G., Panagiotopoulou, A., Nikolić, N., Janković,D., Djokić, D., Raptopoulou, C.P., Terzis, A., Papagiannopoulou, D., Pelecanou, M.,Papadopoulos, M., Pirmettis, I.Benzimidazole derivatives as NSO ligands for the fac-[M(CO)3]+ (M = Re, 99mTc)Inorganica Chimica Acta, 377, pp. 62-68, 2011

43. Kostakis, G.E., Casella, L., Boudalis, A.K., Monzani, E., Plakatouras, J.C.Structural variation from 1D chains to 3D networks: A systematic study ofcoordination number effect on the construction of coordination polymers usingthe terephthaloylbisglycinate ligandNew Journal of Chemistry, 35, pp. 1060-1071, 2011

44. Sarma, R., Deka, H., Boudalis, A.K., Baruah, J.B.Coordination polymers of lanthanide(III): Toward encapsulation of well-definedassembly of guest moleculesCrystal Growth & Design, 11, pp. 547-554, 2011

45. Iannotti, V., Amoruso, S., Ausanio, G., Wang, X., Lanotte, L., Barone, A. S.,Margaris, G., Trohidou, K. N., Fiorani, D.Interplay between particle anisotropy and exchange interaction in Fenanoparticle filmsPhysical Review B83 (21), art. no. 214422, 2011.

46. Kosionis, S.G., Terzis, A.F., Simserides, C., Paspalakis, E.Intrinsic optical bistability in a two-subband system in a semiconductor quantumwell: Analytical resultsJ. Appl. Phys. Volume: 109 (6) art. no 063109, 2011

47. Theophilou, Iris and Thanos, S..Molecular Physics, 109 (11), pp. 1495, 2011

48. Christofi, A., Stefanou, N., and Gantzounis, G.Phys. Rev. B 83, 245126, 2011

49. Christofi, A., Stefanou, N., Gantzounis, G., and Papanikolaou, N.Phys. Rev. B 84, 125109, 2011


50. Chatzipavlidis, A., Bilalis, P., Efthimiadou, E.K., Boukos, N., Kordas, G.C.Sacrificial template-directed fabrication of superparamagnetic polymermicrocontainers for pH-activated controlled release of Daunorubicin.Langmuir, 27, pp. 8478-8485, 2011

51. Efthimiadou, E.K., Tapeinos, C., Bilalis, P., Kordas, G.New approach in synthesis, characterization and release study of pH-sensitivepolymeric micelles, based on PLA-Lys-b-PEGm, conjugated with doxorubicin.Journal of Nanoparticle Research, 13, pp. 6725-6736, 2011

52. Mekeridis E., Kartsonakis I.A., Pappas G., Kordas G.Release studies of corrosion inhibitors from Cerium Titanium OxideNanocontainers.J. Nanopart. Res. 13, pp. 541-554, 2011

53. Balaskas A.C., Kartsonakis I.A., Kordas G.C., Cabral A.M., Morais P.J.Influence of the doping agent on the corrosion protection properties ofpolypyrrole grown on aluminium alloy 2024-T3.Prog. Org. Coat. 71, pp. 181-187, 2011

54. Kartsonakis I.A., Balaskas A.C., Kordas G.C.Influence of Cerium Molybdate Containers on the Corrosion Performance of Epoxycoated Aluminium Alloys 2024-T3.Corros. Sci. 53, pp. 3771-3779, 2011

55. Balaskas A.C., Kartsonakis I.A., Snihirova D., Montemor M. F., Kordas G.Improving the Corrosion Protection Properties of Organically Modified Silicate –Epoxy Coatings by Incorporation of Organic and Inorganic Inhibitors.Prog. Org. Coat. 72, pp. 653-662, 2011

56. Casitas, A., Ioannidis, N., Mitrikas, G., Costas, M., Ribas, X.Aryl-O reductive elimination from reaction of well-defined aryl-Cu(III) species withphenolates: the importance of ligand reactivity.Dalton Trans. 40, pp. 8796-8799, 2011.

57. Michael, C.T., Zacharias, Ν., and Hein, Α.Thick source alpha particle spectroscopy: possibilities and prospectsMediterranean Archaeology and Archaeometry, Vol 10, No. 4 (2010) pp. 99 –105, (Printed July 2011).

58. Dotsika E., Zisi N., Tsoukala E., Poutoukis D., Lykoudis S., Giannakopoulos A.Palaeo-climatic information from isotopic signatures of late pleistocene ursusingressus bone and teeth apatite (Loutra Arideas Cave, Macedonia, N. Greece).Quaternary International, 242, issue 2, 291-301, 2011.


59. Dotsika E., Tzavidopoulos I., Poutoukis D., Raco B., Maniatis Y., Ignatiadou D.Isotope contents, Cl/Br ratio and origin of water at Pikrolimni Lake: a natronsource in ancient Greece, as archive of past environmental conditions. QuaternaryInternational, (doi:10.1016/j.quaint.2011.03.033), 2011.

60. Ghilardi M., Psomiadis D., Cordier S., Sabatier D., Demory F., Hamidi F.,Paraschou T., Dotsika E., Fouache Ε.The impact of early- to mid-holocene palaeoenvironmental changes on Neolithicsettlement at Nea Nikomideia, Thessaloniki plain, Greece.Quaternary International, (doi:10.1016/j.quaint.2010.12.016), 2011.

61. Dotsika E., Raco B., Poutoukis D., Psomiadis D., Kloppmann W., Zisi N.Boron contents in Greek: fresh and thermal waters. Edition Springer (Book, Ch.15) in the “NATO Science for Peace and Security Series-C”, 2011.

62. Alexandrakis V., Speliotis T., Manios E, Niarchos D., Fidler J., Lee J., Varvaro G.Hard/graded exchange spring composite media based on FePtJ. of Applied Physics 109 (7): Art. No. 07B729 APR 1 2011

63. Lee J., Alexandrakis V., Fuger M., Dymerska B., Suess D., Niarchos D., Fidler J.FePt L10/A1 graded media with a rough interphase boundaryApplied Physics Letters 98 (22): Art. No. 222501 MAY 30 2011

64. Giannopoulos D., Th. Speliotis, W.F. Li, G. Hadjipanayis and D. NiarchosStructural and magnetic properties of L10/A1, FePt nanocompositesJ. Magn. Magn. Mater. DOI: 10.1016/j.jmmm.2012.08.003

65. Xu H., Kolthammer J., Rudge J., Girgis E., Choi B. C, Hong Y.K., Abo G., Speliotis T.,Niarchos D., Magnetization Process in Vortex-imprinted Ni80Fe20/Ir20Mn80Square ElementsJournal of Magnetics 16 (2): 83-87 (2011)

66. R. Tarkhanyan, D. Niarchos,Nonradiative surface electromagnetic waves at the interface of uniaxiallybianisotropic enantiomeric media,Phys. Stat. Sol.(b) Vol 248, Issue 6, 1499-1504(2011)

67. N. Lagos, M.M. Sigalas, and D. NiarchosThe optical absorption of nanowire arraysPhotonics and Nanostructures – Fundamentals and Applications 9 (2011) 163–167

68. Fotopoulos, A.; Arvanitidis, J.; Christofilos, D.; Papaggelis, K.; Kalyva, M.; Triantafyllidis,K.; Niarchos, D.; Boukos, Nikos; Basina, G.; Tzitzios, V.One Pot Synthesis and Characterization of Ultra Fine CeO(2) and Cu/CeO(2)Nanoparticles. Application for Low Temperature CO OxidationJ. of Nanscience and Nanotechnology Volume: 11 Issue: 10 Pages: 8593-8598 DOI:10.1166/jnn.2011.4752, Published: OCT 2011


69. Zitko R.; Van Midden H. J. P.; Zupanic E., A. Prodam, S. S. Makridis, D. Niarchosand A. StumbosInt. J of Hydrogen Energy Volume: 36 Issue: 19 Pages: 12268-12278 DOI:10.1016/j.ijhydene.2011.06.087 Published: SEP 2011

70. Markou A.; Panagiotopoulos I.; Bakas T.; D. Niarchos, G. Safran, Wangfeng Li andG. HadjipanayisFormation of L1(0) with (001) texture in magnetically annealed Co/Pt multilayersJ of Applied Physics Volume: 110 Issue: 8 Article Number: 083903 OCT 152011

71. V. Tzitzios, G. Basina, D. Niarchos, Wanfeng Li and G. HadjipanayisSynthesis of air stable FeCo nanoparticles,Journal of Applied Physics , 109, 07A313(2011)

72. Thangadurai, P., Zergioti, I., Saranu, S., Chandrinou, C., Yang, Z., Tsoukalas, D.,Kean, A., Boukos, N.ZnO nanoparticles produced by novel reactive physical deposition processApplied Surface Science, 257 (12), pp. 5366-5369 (2011).

73. Photopoulos, P., Boukos, N., Panagopoulou, M., Meintanis, N., Pantiskos, N.,Raptis, Y., Tsoukalas, D.Size control of Ag nanoparticles for SERS sensing applicationsProcedia Engineering, 25, pp. 280-283 (2011).

74. Papavassiliou, G., Argyriou, D., Panopoulos, N., Koumoulis, D., Boukos, N., Fardis,M., Pissas, M., Kim, H.-J., Yoo, S.-J.MHz Broadline NMR and HRTEM in the study of novel strongly correlated electronmaterialsJournal of Analytical Science & Technology, 2 (Suppl. A), pp. A31-37, 2011.

75. Tziotziou, M., Karakosta, E., Karatasios, I., Diamantopoulos, G., Sapalidis, A.,Fardis, M., Maravelaki-Kalaitzaki, P., Papavassiliou, G., Kilikoglou, V.Application of 1H NMR to hydration and porosity studies of lime-pozzolanmixturesMicroporous and Mesoporous Materials, 139, pp. 16-24, 2011

76. Vasiliadou, I.A., Papoulis, D., Chrysikopoulos, C.V., Panagiotaras, D., Karakosta, E.,Fardis, M., Papavassiliou, G.Attachment of Pseudomonas putida onto differently structured kaoliniteminerals: A combined ATR-FTIR and 1H NMR studyColloids and Surfaces B: Biointerfaces, 84, pp. 354-359, 2011


77. Matsouka, V., Konsolakis, M., Yentekakis, I.V., Papavasiliou, A., Tsetsekou, A.,Boukos, N.Thermal aging behavior of Pt-only TWC converters under simulated exhaustconditions: Effect of rare earths (CeO 2, La 2O 3) and alkali (Na) modifiersTopics in Catalysis, 54 (16-18), pp. 1124-1134 (2011).

78. Rajasudha, G., Nancy, A.P., Paramasivam, T., Boukos, N., Narayanan, V., Stephen,A.Synthesis and characterization of polyindole-NiO-based composite polymerelectrolyte with LiClO 4International Journal of Polymeric Materials, 60 (11), pp. 877-892 (2011).

79. Papavasiliou, A., Tsetsekou, A., Matsouka, V., Konsolakis, M., Yentekakis, I.V.,Boukos, N.Synergistic structural and surface promotion of monometallic (Pt) TWCs:Effectiveness and thermal aging toleranceApplied Catalysis B: Environmental, 106 (1-2), pp. 228-241 (2011).

80. Alexiadis, V.I., Boukos, N., Verykios, X.E.Influence of the composition of Fe 2O 3/Al 2O 3 catalysts on the rate ofproduction and quality of carbon nanotubesMaterials Chemistry and Physics, 128 (1-2), pp. 96-108 (2011).

81. Tsiourvas, D., Tsetsekou, A., Kammenou, M.-I., Boukos, N.Controlling the formation of hydroxyapatite nanorods with dendrimersJournal of the American Ceramic Society, 94 (7), pp. 2023-2029 (2011).

82. Belesi, M., Panagiotopoulos, I., Pal, S., Hariharan, S., Tsitrouli, D., Papavassiliou,G., Niarchos, D., Boukos, N., Fardis, M., Tzitzios, V.Decoration of carbon nanotubes with CoO and Co nanoparticlesJournal of Nanomaterials, 2011, art. no. 320516 (2011).

83. Balis, N., Dracopoulos, V., Stathatos, E., Boukos, N., Lianos, P.A solid-state hybrid solar cell made of nc-TiO 2, CdS quantum dots, and P3HT with2-amino-1-methylbenzimidazole as an interface modifierJournal of Physical Chemistry C, 115 (21), pp. 10911-10916 (2011).

84. Maniatis, Y., Papadopoulos, S.Radiocarbon dating of a Final Neolithic – Early Bronze Age transition periodsettlement at Aghios Ioannis on Thassos (North Aegean)Radiocarbon, 53(1), pp. 21-37, 2011.

85. Maniatis, Y., Ziota, Ch.Systematic radiocarbon dating of a unique Early and Middle Bronze Age cemeteryat Xeropigado Koiladas, West Macedonia, GreeceRadiocarbon, 53(3), pp. 461–478, 2011.


86. Xaplanteris C. L. and Filippaki E.Nonlinear wave phenomena into plasma. Some cases of stabilization and controlof chaotic statesJournal of Plasma Physics, 77 (5), pp 679-692, 2011

87. Xaplanteris C. L.Further research of the collisional instability. An extensive study of growth and anotable influence of the boundariesJournal of Plasma Physics, 77 (1), pp 15-29, 2011

88. Xaplanteris C. L.Drift instabilities’ interaction: A tightening of the B-direction component on theamplitude of the azimouthally propagating waveJournal of Plasma Physics, 77 (3), pp 405-418, 2011

89. Athanassas, C.Constraints on the precision of SAR in equivalent dose estimations close tosaturation in quartz.Geochronometria, 38, pp. 413-423, 2011

90. Pagonis, V., Adamiec, G., Athanassas, C., Chen, R., Baker, A., Larsen, M.,Thompson, Z.Accuracy and precision of the Re-SAR dating protocol for quartz: a simulationsapproach.Nuclear Inst. and Methods in Physics Research, B, 269, pp. 1431-1443, 2011

91. Tzanis C., Varotsos C.,Christodoulakis J.,Tidblad J., Ferm M., Ionescu A.,LefevreR.A., Theodorakopoulou K., and Kreislova K.,On the corrosion and soiling effects on materials by air pollution in Athens,Greece.Atmospheric Chemistry and Physics 11 (23), pp.12039-12048. 2011

92. Vermisoglou, E.C., Pilatos, G., Romanos, G.E., Devlin, E., Kanellopoulos,N.K., Karanikolos, G.N.Magnetic carbon nanotubes with particle-free surfaces and high drug loadingcapacityNanotechnology 22 (35), Article number355602, 2011

93. Xanthopoulou G.,SHS2011,Eurasian Chemico-Technological Journal, v.13, n.3-4, 2011, p.112-114


Published Conference Proceedings

1. Paliadeli, Ch., Papageorgiou, P., Maniatis, Y., Triantafyllou, S., Kyriakou, A.,Tourtas A.Micro-excavation in an unexpected find in the Agora of Aegae, Vergina:Interdisciplinary approach (in Greek)To Archaeologiko Ergo stin Macedonia kai Thraki, Proceedings of the 22nd

Conference 2008, P. Adam-Veleni and K. Tzanavari (eds), Thessaloniki, pp. 183-190, 2011.

2. Maniatis, Y.Investigation of techniques, raw materials and colours for the manufacturing ofthe early vitreous materialsYALOS, Conservation Meeting at the Archaeological Museum of Thessaloniki2009, Ch. Gatzolis (ed.), Archaeological Museum of Thessaloniki, Thessaloniki, pp.11-28, 2011.

3. Papadopoulou, E., Maniatis, Y.Reconstructing the thermal processing techniques of food: The application of FTIRspectroscopy in the analysis of clay thermal structures from EBA ArchontikoProceedings of International Conference on Subsistence, Economy and Society inthe Greek World: Improving the integration of Archaeology and Science, 22-24March, 2010, Athens, in press.

4. Maniatis, Y., Tsirtsoni, Z., Oberlin, Ch., Darcque, P. Koukouli- Chryssanthaki, Ch.Malamidou, D., Siros, T., Miteletsis, M., Papadopoulos, S., Kromer, B.New radiocarbon evidence for the Late Neolithic – Early Bronze Age transition insoutheast EuropeProceedings of the 38th International Symposium on Archaeometry, Tampa, USA,Journal of Open Archaeometry, in press.

5. Longinelli A., Dotsika E., Silvestri A., Poutoukis D., Ignatiadou D. δ18Ο and chemicalmeasurements of Greek Roman glass. International Symposium on “History,Technology and Conservation of Ancient Metal, Glasses and Enamels”, Athens,2011.

6. Mastrotheodoros, G., Beltsios, C., Zacharias, N.Iron based and other ancient pigments for pottery decoration MaterialsProceedings of the 5th International Conference on Emerging Technologies inNon-Destructive TestingIoannina, Greece, pp.19-21, 2011

7. Xaplanteris C.L., Filippaki E., Mistakidis I.S.Collision Frequency leads the Plasma in a Chaotic State. Influence on theConductivity


Proceedings of the 4th Chaotic Modeling and Simulation InternationalConference,Agios Nikolaos, Crete Greece, pp. 635-642, 2011

8. Xaplanteris C. L. and Filippaki E.Drift waves’ synchronization by using an external signal. The stabilization of achaotic plasma turbulenceCHAOS THEORY: Modeling, Simulation and Applications, C. H. Skiadas, I.Dimotikalis, and C. Skiadas (Eds), World Scientific Publishing Co. Selected papersfrom the 3rd Chaotic Modeling and Simulation International Conference (CHAOS2010), pp. 431-438, 2011

9. Sanakis, Y.Spin Relaxation in trinuclear clusters comprising half integer spin ions.EUROMAR 2011, 21-25 August 2011, Frankfurt am Main, Germany, p. 205 in thebook of abstracts.

10. E. Simoen, J. Lauwaert, H. Vrielinck, V. Ioannou-Sougleridis, A. Dimoulas,A deep-level transient spectroscopy study of implanted Ge p +n and n +pjunctions by Pt-induced crystallization,ECS Transactions 41 (7) , pp. 299-308 (2011)

11. A. Molle, S. Baldovino, L. Lamagna, S. Spiga, A. Lamperti, M. Fanciulli, D.Tsoutsou, E. Golias, A. Dimoulas, G. Brammertz, C. Merckling, M. Caymax,Active trap determination at the interface of Ge and In 0.53Ga 0.47As substrateswith dielectric layers,ECS Transactions 41 (3) , pp. 203-221 (2011)

12. M. S. Rahman , E. K. Evangelou, N. Konofaos, A. Dimoulas, Electrical reliabilitycharacteristics and dielectrics degradation in gate stacks (REO-HfO 2) grown onthe high mobility Ge substrates, 2011 International Semiconductor DeviceResearch Symposium, ISDRS 2011 , art. no. 6135221 (2011)

13. Turbanti-Memmi, I. (Editor), Maniatis, Y. (ass. Editor).Proceedings of the 37th International Symposium on Archaeometry, 12-16 May2008, I., Springer, Heidelberg, 2011.

Other Publications

1. Trohidou, K. , Vasilakaki, M. (Chapter in Book)Monte Carlo Studies of Magnetic NanoparticlesApplications of Monte Carlo Method in Science and Engineering, NumericalAnalysis and Scientific Computing, Edited by Shlomo Mark and Shaul Mordechai,Ch. 20, pp 513-538, 2011, InTech, Croatia, ISBN 978-953-307-691-1, DOI:10.5772/15930.


2. S. Abd El Salam and Y. Maniatis, “Characterization of plasters on stone and mudwalls from ancient Pella”, Report submitted to the director of the PellaExcavations, Prof. I. Akamatis, May 2011.

3. M. Maniati, Th. Pitsios, and Y. Maniatis,“Investigation of the human diet in Pella during the Prehistoric and ClassicalPeriod” (in Greek)Report to the Director of Pella Excavations, Prof. I. Akamatis, June 2011.

4. Sanakis, Y., Mitrikas, G., Petrouleas, V., Deligiannakis, Y.Present day EPR spectroscopy in GreeceEPR Newsletter, 21 (1), pp 11-12, 2011.

PROJECTS

Documents

ΒΙΟΑΝΟΡΓΑΝΑ ΚΑΤΑΛΥΤΙΚΑ ΚΕΝΤΡΑ ΚΑΙ … · karaindrou Κ. 18. karapati s. 19. kaparou m. 20. kazantzaki Μ. 21. koumoulis d. 22. kyropoulou d. 23. maniati