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Nanotechnology
Nanotechnology
Nanotechnology
Nanotechnology: General Information and Background
Nanotechnology is a concept, a term that refers to many different
technologies.
All of these technologies are extremely small in scale – ―nano‖ is a
measurement that refers to the nanometre or 10-9 m.
A nanometre is the width of 10 hydrogen atoms lined up side-by-side. To
put this in perspective, a human hair is about 80,000 nanometres wide; the
head of a pin is about 1 million nanometres wide; a red blood cell is about
7,000 nanometres in diameter
A nanometer is the amount a man's beard grows in the time it takes him to
raise the razor to his face
The raw materials and some of the products of nanotechnology are all
extremely small in physical scale.
Nanoscience and nanotechnology often focus on the manipulation of the
most basic components of all matter — atoms and molecules — with great
precision
Nanotechnology
Nanotechnology: General Information and Background
Public Health and Toxicity Concerns
Public health concerns about nanotechnology products focus on
interactions between them and biological tissues and processes.
Some nanostructures may accumulate within tissues and organs and can
be taken up by individual cells.
Nanoscale particles and structures into cells do not seem to affect the
immune responses of cells that introducing larger particles and structures
do.
This ability not to trigger the immune system may be an advantage in
targeting specific cells with introduced drugs, but the particles may still have
some unintended effects. This means that nanostructures. although
attractive as potential drug delivery mechanisms may be a health hazard.
The extremely small size of nanostructures leads some to worry that the
structures might enter the food chain undetected.
Nanotechnology
• Materials reduced to the nanoscale can show different properties compared to
what they exhibit on a macroscale, enabling unique applications.
• For instance, opaque substances become transparent (copper); stable
materials turn combustible (aluminum); solids turn into liquids at room
temperature (gold); insulators become conductors (silicon).
• A material such as gold, which is chemically inert at normal scales, can serve
as a potent chemical catalyst at nanoscales. Much of the fascination with
nanotechnology stems from these quantum and surface phenomena that matter
exhibits at the nanoscale.
Lubick, N. (2008). Silver socks have cloudy lining. Environ Sci Technol. 42(11):3910 quoted in WikiPedia
Nanotechnology
Nanotechnology: General Information and Background
Nanomedicine:
Suggested applications in nanomedicine include:
Rapid cardiovascular repair
Treatments for pathogenic disease and cancer
Responses to physical traumas, with new methods of first aid
Surgery, and emergency or critical care
Neurography, spinal restoration and brain repair (nanostructures)
Nutrition and digestion
Reproductive modifications
Cosmetics
Sports and recreation – performance augmentation
Veterinary and space medicine
Strategies for biostasis and the control of aging processes;
human augmentation systems
By: Donald E. Marlowe
• Controlled molecular assembly : molecular assemblers will position molecules, bringing them together in a specific position, orientation, and sequence.
• By holding and positioning molecules, assemblers will control how the molecules react, building complex structures with atomically precise control.
• The parts are nanometer scale, and the transferred parts are just a few atoms large, shifting from handle to workpiece through a chemical reaction at a specific site.
• An assembler will work as part of a larger system that prepares tools, puts them on the conveyor, and controls the programmable positioning mechanism
The molecular-assembler concept
The molecular-assembler concept
• Their small moving parts will enable them to operate at high frequencies: because each motion traverses less than a millionth of a meter, each can be completed in less than a millionth of a second.
• This enables extremely high productivity.
• Machines of this sort will be complex systems that are several technology generations away. Indeed, no one is even trying to directly build molecular assemblers today, because nanotechnology is still in its infancy.
• We can see a path to assemblers and the early machines may resemble the small, simple productive nanosystems in nature and in biotechnology.
Molecular Manufacturing
• Molecular manufacturing will bring both great opportunities and great potential for abuse.
• Advanced systems could be used to build large, complex products cleanly, efficiently, and at low cost.
• Building with atomic precision, desktop-scale (and larger) manufacturing systems could produce the products like the following, with consequences for many global problems:
• Inexpensive, efficient solar energy systems, a renewable, zero-carbon emission source
• Desktop computers with a billion processors
• Medical devices able to destroy viruses and cancer cells without damaging healthy cells
• Materials 100 times stronger than steel
• Superior military systems
• More molecular manufacturing systems
Nanotechnology Molecular Manufacturing
Nanotechnology: General Information and Background
In Nanosystems, Dr. Drexler proposed and analyzed a variety of molecular
machines, including some too large to be specified and analyzed in atomic
detail. One such machine was a sorting rotor based upon modulated
receptors designed to bind and transport chemical species from a feedstock
solution. One of Dr. Drexler’s more recent projects has been to design in
atomic detail a simpler pump intended to provide some of the functionality of
the larger and more complex sorting rotors.
The pump and segment of chamber wall pictured here contain 6165 atoms.
Nanopore sensor
Nanopore Sensor
Applied voltage draws a DNA strand
and surrounding ionic solution
through a pore of nanometer
dimensions. The various DNA units
in the strand block ion flow by
differing amounts. In turn, by
measuring these differences in ion
current, scientists can detect the
sequence of DNA units. Atomistic
scale simulations performed on the
NASA Columbia supercomputer
(SGI Altix-3000) allow detailed study
of DNA translocation to enhance the
abilities of these sequencers. Solid-
state nanopores offer a better
temporal control of the translocation
of DNA, and a more robust template
for nano-engineering than biological
ion channels. The chemistry of solid-
state nanopores can be more easily
tuned to increase the signal
resolution. These advantages will
results in real-time genome
sequencing..
NASA Ames nanotechnology
Nanolasers
The complex interaction between light and nanometer structures, like wires, has possibilities as new
technology for devices and sensors. NAS researchers are studying light emission from a semiconductor
nanowire-typically 10-100 nanometers wide and a few micrometers long-which functions as a laser.
Lasers made from arrays of these wires have many potential applications in communications and sensing
for NASA.
NASA Ames nanotechnology
Nanowire
An engineered DNA strand between metal atom contacts
could function as a molecular electronics device.
Such molecules and nanostructures are expected to
revolutionize electronics. Understanding the
complex quantum physics involved via simulation
guides design.
AN ENGINEERED DNA STRAND
NASA Ames nanotechnology
Carbon Nanotubes - SEM Images
• Neural tree with 14 symmetric Y-junctions
• Branching and switching of signals at each junction similar to what happens in biological
neural network
• Neural tree can be trained to perform complex switching and computing functions
• Not restricted to only electronic signals; possible to use acoustic, chemical or thermal
signals
A novel data storage
system capable of
1015 bytes/cm2 is being
explored.
In this system, H atoms
would be designated as 0
and F atoms as 1.
A tip that can distinguish
between 0 and 1 rapidly
and unambiguously
is being investigated.
NASA Ames nanotechnology
Nano and BioTechnology Research at NASA Ames
M. Meyyappan and Harry Partridge
NASA Ames Research Center
Moffett Field, CA 94035
Abstract
This article provides an overview of nanotechnology and
biotechnology research at NASA Ames Research Center
and covers current results in the areas of carbon
nanotube (CNT) growth and characterization and
functionalization, nanotubes in scanning probe
microscopy, inorganic nanowires, biosensors, chemical
sensors, nanoelectronics optoelectronics, computational
nanotechnology, quantum device simulation, and
computational optoelectronics.
Link to Report