| Nanotechnology and The Little Old Man
Posted: 5/14/2008 7:51:25 PM | Nanotechnology
Very simple terminology,
Just the prefix Nano- is used a lot lol. Don't let it scare you away!
Our Living Language : Nanotechnology is the science and technology of precisely manipulating the structure of matter at the molecular level. The term nanotechnology embraces many different fields and specialties, including engineering, chemistry, electronics, and medicine, among others, but all are concerned with bringing existing technologies down to a very small scale, measured in nanometers A nanometer—a billionth of a meter—is about the size of six carbon atoms in a row. (The prefix nano- comes from the Greek word nanos, which meant "little old man" or "dwarf.") Today, as in the past, most industrial products are created by pushing piles of millions of atoms together—by mixing, grinding, heating—a very imprecise process. However, scientists can now pick up individual atoms to assemble them into simple structures or cause specific chemical reactions. Propellers have been attached to molecular motors, and electricity has been conducted through nanowires. Nanotubes made of carbon are being investigated for a variety of industrial and research purposes. In the future, nanotechnology may be able to harness the forces that operate at the scale of the nanometer, such as the van der Waals force, as well as changes in the quantum states of particles, for new engineering purposes. The development of nanotechnology holds out great promise of improvements in the quality of life, including new treatments for disease and greater efficiency in computer data storage and processing. For example, tiny autonomous robots, or nanobots, may one day be sent into human bodies to repair cells and cure cancers, perhaps even extending the human life span by many years. The simple devices created by nanotechnology so far have not yet approached the complexity of the envisioned nanomachines and nanobots. Some scientists even see a dark side to the technology, emphasizing the need for caution in its development, particularly in attempts to create nanobots that can replicate themselves like living organisms.
Brief of Cnts
WHAT ARE CARBON NANOTUBES? Carbon nanotubes are tubular forms of carbon that can be envisaged as graphitic sheets rolled into cylindrical form. These nanotubes have diameters in the range of few nanometers and their lengths are up to several micrometers. Each nanotube is a single molecule made up of a hexagonal network of covalently bonded carbon atoms.
Carbon nanotubes are of two types: single-walled and multi-walled. A single-walled carbon nanotube (SWNT) consists of a single grapheme cylinder, whereas a multi-walled carbon nanotube (MWNT) comprises several concentric grapheme cylinders.
Strong covalent bonding, unique one-dimensional structure and nanometer size, together impart unusual properties to the nanotubes. These properties include exceptionally high tensile strength, high resilience, electronic properties ranging from metallic to semi-conducting, the ability to sustain high current densities and high thermal conductivity. Thus carbon nanotubes could be used as fillers in super-strong composite materials, as wires and components in nano-electronic devices, as tips of scanning probe microscopes and in flat panel displays and gas sensors.
Nanotubes are interesting to me because they can be used in chemistry,- biology,- medicine ,- physics, engineering, and electronics. It is also used to make bullet proof vests(chemistry), Touch Screen Displays,(electronics)- and more.
Question; what is the name of at least 1 product, device, field, (it could be of any size),- chemical, drug, etc. that currently uses this technology?
a hint would be; belongs as a part, member, accessory, or product of chemistry,- biology,- medicine ,- physics, engineering, and, or electronics.
Good Luck! | |
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| Nanotechnology and The Little Old Man
Posted: 5/15/2008 1:44:14 PM | ----------------------------------------------------------------------------------------------------------------------------------
here is a link from last year on plentyoffish;
http://forums.plentyoffish.com/datingPosts7361778.aspx
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here is a URL of how much this field has advanced since last year.;
http:http://uwnews.org/article.asp?articleID=1464
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| Nanotechnology and The Little Old Man
Posted: 5/16/2008 4:57:41 PM |
Question; what is the name of at least 1 product, device, field, (it could be of any size),- chemical, drug, etc. that currently uses this technology?
a hint would be; belongs as a part, member, accessory, or product of chemistry,- biology,- medicine ,- physics, engineering, and, or electronics.
When you say "this technology", do you mean the nanotubes or nanotech in general? If you mean in general, then there are a few high tech steel alloys that are assembled atom by atom, they're prefaced by "CPM" (crucible particle metallurgy) in the alloy designation, such as CPM S30V. What this process does is allow microstructures and homogenousness that would be impossible with standard methods, such as making carbides smaller than they'd naturally form. Basically, you can make the steel better than you normally could concidering the alloy components. | |
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| Nanotechnology and The Cellular Phone
Posted: 5/17/2008 11:27:07 AM | Hi AwP,
Speaking overall YES. This phenomenon would be directly related to "Chemistry and Physics Dept",
nanotubes; there is actually a German Corporation that sells them. I was listening to a "pod cast" of University of Washington, reporting on this subject, and they had a convention, on nano- science,
nano-tech, nano-me, nano- you nano-whatever, lol.
The fact of the matter is that, the salespersons, representing a wide array of these nano- technology corporations, had a problem, because, even though,- they have the actual products,- machines,
etc.- ON hand, unfortunately, they did NOT find people smart enough that knew much about this field.
nanotubes or nanotech in general?
I will add some amazing news, regarding;" nanotubes". It will be quite complex to explain !
Current project underway has to do with monitoring bodily fluids, to check sugar levels, and help in keeping an keen eye on the patient, mostly in remote parts of the world, such as Africa, and India, - in -which there is hardly any doctor care.
These devices will transmit data, via a cell phone, the technical part is how the machine can actually
convert a chemical reaction data to digital data. I believe the devices under way , can detect traces of gases also.
The factors they are working on are;
1) mass production, so that a poor person can afford it
2) to maintain the waste product,
3)the actual release of the medication, automatically when needed.
nanotubes are the " just what it sounds like TUBES?
nanotubes are going to be made on a, device similar to your computer printer, they put a silicone or mixed compound sheet in this, printer like machine.
What happens is that they manipulate, these sheets to make these grooves in the paper, to make a credit card insert, for the cell phone device, that does all the work, by having nano- type pumps , to create a flow.
111incogneto. | |
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| Nanotechnology and The Cellular Phone
Posted: 5/18/2008 4:35:24 PM | Dang that Robin Williams..."nano-nano!"
Mankind is trying to develope ways to make his world better. Nanotech could do this. Just think....buildings made with nanotech...with a built-in "best before" date. This would be keeping the construction industry going on forever. You computer becomes a blob of gelatinous mass after 5 years...time for a new one. Healthcare....oops...you reached 100...all nano machines in you automatically shut down, you are on your own.
Could we really live in a society that would even aloow this? We already do. The washer and dryer your grandmother bought in 1969 still runs (with a couple small repairs)...but the one you got 3 years ago has needed repairs already...twice, and is ready for replacement! Seals shot or whatever was built into it to make sure it needed to be replaced within six months of having finished the payments. Same with cars. Same with almost anything manufactured today. So..nanotechnology will simply "fine-tune" this consumerism.
It could be a boon to mankind...but I wouldn't bet on it unless there was a REAL watchdog on it that has some teeth. Otherwise.... | |
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| Nanotechnology and The Little Old Man
Posted: 5/18/2008 7:26:44 PM | OLEDs already used in some cell phones. a $3200 11" OLED tv is in production.
Flatter, sharper, blah blah...
They are already building AMOLEDs (active matrix organic light-emitting diode)
see http://pubs.acs.org/journals/nalefd/articleWindow.html.
But it's all over the place. Not just display. Rice University has just created the "New Black". The darkest material known. Made of stack walled nanotubes. Why is a black black good? The nanotube forest only reflects 0.1% of the light that falls on it. Makes for a better solar collector, infrared detectors, and more. | |
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| Nanotechnology and The Little Old Man
Posted: 5/21/2008 3:25:34 PM | I participated in a science project and I won " Honorable Mention"!
The subject was "Solar Radiator" I have to dig up the paper. Here is what I did;
I took a piece of copper pipe, bend it at many angles, to resemble a miniature radiator, then painted it black.
I would pour cold water in one end, and by using solar rays, ( attracted to the black paint) the water would pour out on the other end, boiling hot! The "black attracts sun rays" I would imagine all of the rules of science apply to nano-science.
Before you get started, you would need a Nanotechnology microscope. Called
atomic force microscope (AFM), and the scanning tunneling microscope (STM). Combined with refined processes such as electron beam lithography and molecular beam epitaxy. | |
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| Nanotechnology >>Overview>>Origins>>Fundamental concepts>>Cu.rrent research>Tools and techniques>con
Posted: 5/21/2008 3:38:54 PM | Overview
Nanotechnology >>Overview>>Origins>>Fundamental concepts>>Current research>>Tools and techniques>>Applications>>Health and environmental concerns>>Implications>>
Nanotechnology is a highly multidisciplinary field, drawing from fields such as applied physics, materials science, interface and colloid science, device physics, supramolecular chemistry (which refers to the area of chemistry that focuses on the noncovalent bonding interactions of molecules), self-replicating machines and robotics, chemical engineering, mechanical engineering, biological engineering, and electrical engineering. Grouping of the sciences under the umbrella of "nanotechnology" has been questioned on the basis that there is little actual boundary-crossing between the sciences that operate on the nano-scale. Instrumentation is the only area of technology common to all disciplines; on the contrary, for example pharmaceutical and semiconductor industries do not "talk with each other". Corporations that call their products "nanotechnology" typically market them only to a certain industrial cluster.[1]
Two main approaches are used in nanotechnology. In the "bottom-up" approach, materials and devices are built from molecular components which assemble themselves chemically by principles of molecular recognition. In the "top-down" approach, nano-objects are constructed from larger entities without atomic-level control. The impetus for nanotechnology comes from a renewed interest in Interface and Colloid Science, coupled with a new generation of analytical tools such as the atomic force microscope (AFM), and the scanning tunneling microscope (STM). Combined with refined processes such as electron beam lithography and molecular beam epitaxy, these instruments allow the deliberate manipulation of nanostructures, and lead to the observation of novel phenomena.
Examples of nanotechnology are the manufacture of polymers based on molecular structure, and the design of computer chip layouts based on surface science. Despite the promise of nanotechnologies such as quantum dots and nanotubes, real commercial applications have mainly used the advantages of colloidal nanoparticles in bulk form, such as suntan lotion, cosmetics, protective coatings, drug delivery,[2] and stain resistant clothing.
Origins
Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. Members of the fullerene family are a major subject of research falling under the nanotechnology umbrella.
Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. Members of the fullerene family are a major subject of research falling under the nanotechnology umbrella.
Main article: History of nanotechnology
The first use of the concepts in 'nano-technology' (but predating use of that name) was in "There's Plenty of Room at the Bottom," a talk given by physicist Richard Feynman at an American Physical Society meeting at Caltech on December 29, 1959. Feynman described a process by which the ability to manipulate individual atoms and molecules might be developed, using one set of precise tools to build and operate another proportionally smaller set, so on down to the needed scale. In the course of this, he noted, scaling issues would arise from the changing magnitude of various physical phenomena: gravity would become less important, surface tension and Van der Waals attraction would become more important, etc. This basic idea appears plausible, and exponential assembly enhances it with parallelism to produce a useful quantity of end products. The term "nanotechnology" was defined by Tokyo Science University Professor Norio Taniguchi in a 1974 paper[3] as follows: "'Nano-technology' mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or by one molecule." In the 1980s the basic idea of this definition was explored in much more depth by Dr. K. Eric Drexler, who promoted the technological significance of nano-scale phenomena and devices through speeches and the books Engines of Creation: The Coming Era of Nanotechnology (1986) and Nanosystems: Molecular Machinery, Manufacturing, and Computation,[4] and so the term acquired its current sense. Engines of Creation: The Coming Era of Nanotechnology is considered the first book on the topic of nanotechnology. Nanotechnology and nanoscience got started in the early 1980s with two major developments; the birth of cluster science and the invention of the scanning tunneling microscope (STM). This development led to the discovery of fullerenes in 1986 and carbon nanotubes a few years later. In another development, the synthesis and properties of semiconductor nanocrystals was studied; This led to a fast increasing number of metal oxide nanoparticles of quantum dots. The atomic force microscope was invented six years after the STM was invented. In 2000, the United States National Nanotechnology Initiative was founded to coordinate Federal nanotechnology research and development.
Fundamental concepts
One nanometer (nm) is one billionth, or 10-9 of a meter. To put that scale in context, the comparative size of a nanometer to a meter is the same as that of a marble to the size of the earth.[5] Or another way of putting it: a nanometer is the amount a man's beard grows in the time it takes him to raise the razor to his face.[5]
Typical carbon-carbon bond lengths, or the spacing between these atoms in a molecule, are in the range 0.12-0.15 nm, and a DNA double-helix has a diameter around 2 nm. On the other hand, the smallest cellular lifeforms, the bacteria of the genus Mycoplasma, are around 200 nm in length.
Larger to smaller: a materials perspective
Image of reconstruction on a clean Au(100) surface, as visualized using scanning tunneling microscopy. The positions of the individual atoms composing the surface are visible.
Image of reconstruction on a clean Au(100) surface, as visualized using scanning tunneling microscopy. The positions of the individual atoms composing the surface are visible.
Main article: Nanomaterials
A number of physical phenomena become pronounced as the size of the system decreases. These include statistical mechanical effects, as well as quantum mechanical effects, for example the “quantum size effect” where the electronic properties of solids are altered with great reductions in particle size. This effect does not come into play by going from macro to micro dimensions. However, it becomes dominant when the nanometer size range is reached. Additionally, a number of physical (mechanical, electrical, optical, etc.) properties change when compared to macroscopic systems. One example is the increase in surface area to volume ratio altering mechanical, thermal and catalytic properties of materials. Novel mechanical properties of nanosystems are of interest in the nanomechanics research. The catalytic activity of nanomaterials also opens potential risks in their interaction with biomaterials.
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); inert materials become catalysts (platinum); 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.
Simple to complex: a molecular perspective
Main article: Molecular self-assembly
Modern synthetic chemistry has reached the point where it is possible to prepare small molecules to almost any structure. These methods are used today to produce a wide variety of useful chemicals such as pharmaceuticals or commercial polymers. This ability raises the question of extending this kind of control to the next-larger level, seeking methods to assemble these single molecules into supramolecular assemblies consisting of many molecules arranged in a well defined manner.
These approaches utilize the concepts of molecular self-assembly and/or supramolecular chemistry to automatically arrange themselves into some useful conformation through a bottom-up approach. The concept of molecular recognition is especially important: molecules can be designed so that a specific conformation or arrangement is favored due to non-covalent intermolecular forces. The Watson-Crick basepairing rules are a direct result of this, as is the specificity of an enzyme being targeted to a single substrate, or the specific folding of the protein itself. Thus, two or more components can be designed to be complementary and mutually attractive so that they make a more complex and useful whole.
Such bottom-up approaches should be able to produce devices in parallel and much cheaper than top-down methods, but could potentially be overwhelmed as the size and complexity of the desired assembly increases. Most useful structures require complex and thermodynamically unlikely arrangements of atoms. Nevertheless, there are many examples of self-assembly based on molecular recognition in biology, most notably Watson-Crick basepairing and enzyme-substrate interactions. The challenge for nanotechnology is whether these principles can be used to engineer novel constructs in addition to natural ones.
Molecular nanotechnology: a long-term view
Main article: Molecular nanotechnology
Molecular nanotechnology, sometimes called molecular manufacturing, is a term given to the concept of engineered nanosystems (nanoscale machines) operating on the molecular scale. It is especially associated with the concept of a molecular assembler, a machine that can produce a desired structure or device atom-by-atom using the principles of mechanosynthesis. Manufacturing in the context of productive nanosystems is not related to, and should be clearly distinguished from, the conventional technologies used to manufacture nanomaterials such as carbon nanotubes and nanoparticles.
When the term "nanotechnology" was independently coined and popularized by Eric Drexler (who at the time was unaware of an earlier usage by Norio Taniguchi) it referred to a future manufacturing technology based on molecular machine systems. The premise was that molecular-scale biological analogies of traditional machine components demonstrated molecular machines were possible: by the countless examples found in biology, it is known that sophisticated, stochastically optimised biological machines can be produced.
It is hoped that developments in nanotechnology will make possible their construction by some other means, perhaps using biomimetic principles. However, Drexler and other researchers[6] have proposed that advanced nanotechnology, although perhaps initially implemented by biomimetic means, ultimately could be based on mechanical engineering principles, namely, a manufacturing technology based on the mechanical functionality of these components (such as gears, bearings, motors, and structural members) that would enable programmable, positional assembly to atomic specification (PNAS-1981). The physics and engineering performance of exemplar designs were analyzed in Drexler's book Nanosystems.
But Drexler's analysis is very qualitative and does not address very pressing issues, such as the "fat fingers" and "Sticky fingers" problems. In general it is very difficult to assemble devices on the atomic scale, as all one has to position atoms are other atoms of comparable size and stickyness. Another view, put forth by Carlo Montemagno,[7] is that future nanosystems will be hybrids of silicon technology and biological molecular machines. Yet another view, put forward by the late Richard Smalley, is that mechanosynthesis is impossible due to the difficulties in mechanically manipulating individual molecules.
This led to an exchange of letters in the ACS publication Chemical & Engineering News in 2003.[8] Though biology clearly demonstrates that molecular machine systems are possible, non-biological molecular machines are today only in their infancy. Leaders in research on non-biological molecular machines are Dr. Alex Zettl and his colleagues at Lawrence Berkeley Laboratories and UC Berkeley. They have constructed at least three distinct molecular devices whose motion is controlled from the desktop with changing voltage: a nanotube nanomotor, a molecular actuator, and a nanoelectromechanical relaxation oscillator.
An experiment indicating that positional molecular assembly is possible was performed by Ho and Lee at Cornell University in 1999. They used a scanning tunneling microscope to move an individual carbon monoxide molecule (CO) to an individual iron atom (Fe) sitting on a flat silver crystal, and chemically bound the CO to the Fe by applying a voltage.
Current research
Space-filling model of the nanocar on a surface, using fullerenes as wheels.
Space-filling model of the nanocar on a surface, using fullerenes as wheels.
Graphical representation of a rotaxane, useful as a molecular switch.
Graphical representation of a rotaxane, useful as a molecular switch.
This device transfers energy from nano-thin layers of quantum wells to nanocrystals above them, causing the nanocrystals to emit visible light.
This device transfers energy from nano-thin layers of quantum wells to nanocrystals above them, causing the nanocrystals to emit visible light.[9]
Nanomaterials
This includes subfields which develop or study materials having unique properties arising from their nanoscale dimensions.[10]
* Interface and Colloid Science has given rise to many materials which may be useful in nanotechnology, such as carbon nanotubes and other fullerenes, and various nanoparticles and nanorods.
* Nanoscale materials can also be used for bulk applications; most present commercial applications of nanotechnology are of this flavor.
* Progress has been made in using these materials for medical applications; see Nanomedicine.
Bottom-up approaches
These seek to arrange smaller components into more complex assemblies.
* DNA nanotechnology utilizes the specificity of Watson-Crick basepairing to construct well-defined structures out of DNA and other nucleic acids.
* Approaches from the field of "classical" chemical synthesis also aim at designing molecules with well-defined shape (e.g. bis-peptides[11]).
* More generally, molecular self-assembly seeks to use concepts of supramolecular chemistry, and molecular recognition in particular, to cause single-molecule components to automatically arrange themselves into some useful conformation.
Top-down approaches
These seek to create smaller devices by using larger ones to direct their assembly.
* Many technologies descended from conventional solid-state silicon methods for fabricating microprocessors are now capable of creating features smaller than 100 nm, falling under the definition of nanotechnology. Giant magnetoresistance-based hard drives already on the market fit this description,[12] as do atomic layer deposition (ALD) techniques. Peter Grünberg and Albert Fert received the Nobel Prize in Physics for their discovery of Giant magnetoresistance and contributions to the field of spintronics in 2007.[13]
* Solid-state techniques can also be used to create devices known as nanoelectromechanical systems or NEMS, which are related to microelectromechanical systems or MEMS.
* Atomic force microscope tips can be used as a nanoscale "write head" to deposit a chemical upon a surface in a desired pattern in a process called dip pen nanolithography. This fits into the larger subfield of nanolithography.
Functional approaches
These seek to develop components of a desired functionality without regard to how they might be assembled.
* Molecular electronics seeks to develop molecules with useful electronic properties. These could then be used as single-molecule components in a nanoelectronic device.[14] For an example see rotaxane.
* Synthetic chemical methods can also be used to create synthetic molecular motors, such as in a so-called nanocar.
Speculative
These subfields seek to anticipate what inventions nanotechnology might yield, or attempt to propose an agenda along which inquiry might progress. These often take a big-picture view of nanotechnology, with more emphasis on its societal implications than the details of how such inventions could actually be created.
* Molecular nanotechnology is a proposed approach which involves manipulating single molecules in finely controlled, deterministic ways. This is more theoretical than the other subfields and is beyond current capabilities.
* Nanorobotics centers on self-sufficient machines of some functionality operating at the nanoscale. There are hopes for applying nanorobots in medicine[15][16][17], but it may not be easy to do such a thing because of several drawbacks of such devices.[18] Nevertheless, progress on innovative materials and methodologies has been demonstrated with some patents granted about new nanomanufacturing devices for future commercial applications, which also progressively helps in the development towards nanorobots with the use of embedded nanobioelectronics concept.[19][20]
* Programmable matter based on artificial atoms seeks to design materials whose properties can be easily and reversibly externally controlled.
* Due to the popularity and media exposure of the term nanotechnology, the words picotechnology and femtotechnology have been coined in analogy to it, although these are only used rarely and informally.
Tools and techniques
Typical AFM setup. A microfabricated cantilever with a sharp tip is deflected by features on a sample surface, much like in a phonograph but on a much smaller scale. A laser beam reflects off the backside of the cantilever into a set of photodetectors, allowing the deflection to be measured and assembled into an image of the surface.
Typical AFM setup. A microfabricated cantilever with a sharp tip is deflected by features on a sample surface, much like in a phonograph but on a much smaller scale. A laser beam reflects off the backside of the cantilever into a set of photodetectors, allowing the deflection to be measured and assembled into an image of the surface.
The first observations and size measurements of nano-particles were made during the first decade of the 20th century. They are mostly associated with the name of Zsigmondy who made detailed studies of gold sols and other nanomaterials with sizes down to 10 nm and less. He published a book in 1914.[21] He used ultramicroscope that employs a dark field method for seeing particles with sizes much less than light wavelength.
There are traditional techniques developed during 20th century in Interface and Colloid Science for characterizing nanomaterials. These are widely used for first generation passive nanomaterials specified in the next section.
These methods include several different techniques for characterizing particle size distribution. This characterization is imperative because many materials that are expected to be nano-sized are actually aggregated in solutions. Some of methods are based on light scattering. Other apply ultrasound, such as ultrasound attenuation spectroscopy for testing concentrated nano-dispersions and microemulsions.[22]
There is also a group of traditional techniques for characterizing surface charge or zeta potential of nano-particles in solutions. These information is required for proper system stabilzation, preventing its aggregation or flocculation. These methods include microelectrophoresis, electrophoretic light scattering and electroacoustics. The last one, for instance colloid vibration current method is suitable for characterizing concentrated systems.
Next group of nanotechnological techniques include those used for fabrication of nanowires, those used in semiconductor fabrication such as deep ultraviolet lithography, electron beam lithography, focused ion beam machining, nanoimprint lithography, atomic layer deposition, and molecular vapor deposition, and further including molecular self-assembly techniques such as those employing di-block copolymers. However, all of these techniques preceded the nanotech era, and are extensions in the development of scientific advancements rather than techniques which were devised with the sole purpose of creating nanotechnology and which were results of nanotechnology research.
There are several important modern developments. The atomic force microscope (AFM) and the Scanning Tunneling Microscope (STM) are two early versions of scanning probes that launched nanotechnology. There are other types of scanning probe microscopy, all flowing from the ideas of the scanning confocal microscope developed by Marvin Minsky in 1961 and the scanning acoustic microscope (SAM) developed by Calvin Quate and coworkers in the 1970s, that made it possible to see structures at the nanoscale. The tip of a scanning probe can also be used to manipulate nanostructures (a process called positional assembly). Feature-oriented scanning-positioning methodology suggested by Rostislav Lapshin appears to be a promising way to implement these nanomanipulations in automatic mode. However, this is still a slow process because of low scanning velocity of the microscope. Various techniques of nanolithography such as dip pen nanolithography, electron beam lithography or nanoimprint lithography were also developed. Lithography is a top-down fabrication technique where a bulk material is reduced in size to nanoscale pattern.
The top-down approach anticipates nanodevices that must be built piece by piece in stages, much as manufactured items are made. Scanning probe microscopy is an important technique both for characterization and synthesis of nanomaterials. Atomic force microscopes and scanning tunneling microscopes can be used to look at surfaces and to move atoms around. By designing different tips for these microscopes, they can be used for carving out structures on surfaces and to help guide self-assembling structures. By using, for example, feature-oriented scanning-positioning approach, atoms can be moved around on a surface with scanning probe microscopy techniques. At present, it is expensive and time-consuming for mass production but very suitable for laboratory experimentation.
In contrast, bottom-up techniques build or grow larger structures atom by atom or molecule by molecule. These techniques include chemical synthesis, self-assembly and positional assembly. Another variation of the bottom-up approach is molecular beam epitaxy or MBE. Researchers at Bell Telephone Laboratories like John R. Arthur. Alfred Y. Cho, and Art C. Gossard developed and implemented MBE as a research tool in the late 1960s and 1970s. Samples made by MBE were key to the discovery of the fractional quantum Hall effect for which the 1998 Nobel Prize in Physics was awarded. MBE allows scientists to lay down atomically-precise layers of atoms and, in the process, build up complex structures. Important for research on semiconductors, MBE is also widely used to make samples and devices for the newly emerging field of spintronics.
Newer techniques such as Dual Polarisation Interferometry are enabling scientists to measure quantitatively the molecular interactions that take place at the nano-scale.
Applications
Main article: List of nanotechnology applications
As of April 24, 2008 The Project on Emerging Nanotechnologies claims that over 609 nanotech products exist, with new ones hitting the market at a pace of 3-4 per week.[23] The project lists all of the products in a database. Most applications are limited to the use of "first generation" passive nanomaterials which includes titanium dioxide in sunscreen, cosmetics and some food products; silver in food packaging, clothing, disinfectants and household appliances; zinc oxide in sunscreens and cosmetics, surface coatings, paints and outdoor furniture varnishes; and cerium oxide as a fuel catalyst.[citation needed]
The National Science Foundation (a major source of funding for nanotechnology in the United States) funded researcher David Berube to study the field of nanotechnology. His findings are published in the monograph “Nano-Hype: The Truth Behind the Nanotechnology Buzz". This published study (with a foreword by Mihail Roco, Senior Advisor for Nanotechnology at the National Science Foundation) concludes that much of what is sold as “nanotechnology” is in fact a recasting of straightforward materials science, which is leading to a “nanotech industry built solely on selling nanotubes, nanowires, and the like” which will “end up with a few suppliers selling low margin products in huge volumes." Further applications which require actual manipulation or arrangement of nanoscale components await further research. Though technologies branded with the term 'nano' are sometimes little related to and fall far short of the most ambitious and transformative technological goals of the sort in molecular manufacturing proposals, the term still connotes such ideas. Thus there may be a danger that a "nano bubble" will form, or is forming already, from the use of the term by scientists and entrepreneurs to garner funding, regardless of interest in the transformative possibilities of more ambitious and far-sighted work.
Nanofiltration may come to be an important application, although future research must be careful to investigate possible toxicity.[24]
In 1999, the ultimate CMOS transistor developed at the Laboratory for Electronics and Information Technology in Grenoble, France, tested the limits of the principles of the MOSFET transistor with a diameter of 18 nm (approximately 70 atoms placed side by side). This was almost one tenth the size of the smallest industrial transistor in 2003 (130 nm in 2003, 90 nm in 2004 and 65 nm in 2005). It enabled the theoretical integration of seven billion junctions on a €1 coin. However, the CMOS transistor, which was created in 1999, was not a simple research experiment to study how CMOS technology functions, but rather a demonstration of how this technology functions now that we ourselves are getting ever closer to working on a molecular scale. Today it would be impossible to master the coordinated assembly of a large number of these transistors on a circuit and it would also be impossible to create this on an industrial level.[25]
Cancer
The small size of nanoparticles endows them with properties that can be very useful in oncology, particularly in imaging. Quantum dots (nanoparticles with quantum confinement properties, such as size-tunable light emission), when used in conjunction with MRI (magnetic resonance imaging), can produce exceptional images of tumor sites. These nanoparticles are much brighter than organic dyes and only need one light source for excitation. This means that the use of fluorescent quantum dots could produce a higher contrast image and at a lower cost than today's organic dyes used as contrast media.
Another nanoproperty, high surface area to volume ratio, allows many functional groups to be attached to a nanoparticle, which can seek out and bind to certain tumor cells. Additionally, the small size of nanoparticles (10 to 100 nanometers), allows them to preferentially accumulate at tumor sites (because tumors lack an effective lymphatic drainage system). A very exciting research question is how to make these imaging nanoparticles do more things for cancer. For instance, is it possible to manufacture multifunctional nanoparticles that would detect, image, and then proceed to treat a tumor? This question is under vigorous investigation; the answer to which could shape the future of cancer treatment.[26]A promising new cancer treatment that may one day replace radiation and chemotherapy is edging closer to human trials. Kanzius RF therapy attaches microscopic nanoparticles to cancer cells and then "cooks" tumors inside the body with radio waves that heat only the nanoparticles and the adjacent (cancerous) cells.
Health and environmental concerns
Main article: Nanotoxicology
Some of the recently developed nanoparticle products may have unintended consequences. Researchers have discovered that silver nanoparticles used in socks to reduce foot odor are being released in the wash with possible negative consequences.[27] Silver nanoparticles, which are bacteriostatic, may then destroy beneficial bacteria which are important for breaking down organic matter in waste treatment plants or farms.[28]
A study at the University of Rochester found that when rats breathed in nanoparticles, the particles settled in the brain and lungs, which lead to significant increases in biomarkers for inflammation and stress response.[29]
A major study published more recently in Nature nanotechnology suggests some forms of carbon nanotubes – a poster child for the “nanotechnology revolution” – could be as harmful as asbestos if inhaled in sufficient quantities. Anthony Seaton of the Institute of Occupational Medicine in Edinburgh, Scotland, who contributed to the article on carbon nanotubes said "We know that some of them probably have the potential to cause mesothelioma. So those sorts of materials need to be handled very carefully." [30]
Implications
Main article: Implications of nanotechnology
Due to the far-ranging claims that have been made about potential applications of nanotechnology, a number of serious concerns have been raised about what effects these will have on our society if realized, and what action if any is appropriate to mitigate these risks.
One area of concern is the effect that industrial-scale manufacturing and use of nanomaterials would have on human health and the environment, as suggested by nanotoxicology research. Groups such as the Center for Responsible Nanotechnology have advocated that nanotechnology should be specially regulated by governments for these reasons. Others counter that overregulation would stifle scientific research and the development of innovations which could greatly benefit mankind.
Other experts, including director of the Woodrow Wilson Center's Project on Emerging Nanotechnologies David Rejeski, have testified[31] that successful commercialization depends on adequate oversight, risk research strategy, and public engagement. More recently local municipalities have passed (Berkeley, CA) or are considering (Cambridge, MA) - ordinances requiring nanomaterial manufacturers to disclose the known risks of their products.
The National Institute for Occupational Safety and Health is conducting research on how nanoparticles interact with the body’s systems and how workers might be exposed to nano-sized particles in the manufacturing or industrial use of nanomaterials. NIOSH offers interim guidelines for working with nanomaterials consistent with the best scientific knowledge. [32]
Longer-term concerns center on the implications that new technologies will have for society at large, and whether these could possibly lead to either a post scarcity economy, or alternatively exacerbate the wealth gap between developed and developing nations. The effects of nanotechnology on the society as a whole, on human health and the environment, on trade, on security, on food systems and even on the definition of "human", have not been characterized or politicized.
See also
* American National Standards Institute Nanotechnology Panel (ANSI-NSP)
* Energy Applications of Nanotechnology
* IEST
* List of emerging technologies
* List of nanotechnology organizations
* List of nanotechnology topics
* Mesoporous silicates
* Molecular modelling
* Nanoengineering
* Nanobiotechnology
* Nanofluidics
* Nanoethics
* Nanoscale iron particles
* Nanotechnology education
* Nanotechnology in fiction
* Plug-in hybrid
* Supramolecular chemistry
* Top-down and bottom-up
http://en.wikipedia.org/wiki/Nanotechnology
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| Nanotechnology and The Little Old Man
Posted: 5/26/2008 12:00:09 PM | Composites:
Removing undesirables from water such as mecury and lead.
Crystals:
antimicrobial dressings.. nanocrystalline silver kills a broad spectrum of bacteria in as little as 30 minutes.
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| Nanotechnology and The Little Old Man
Posted: 6/5/2008 11:55:12 PM | Ancient hair dye..
"a hair-dye formula dating to Greek and Roman days works by causing tiny nanocrystals to form deep inside strands of hair.
Cosmetics were known thousands of years ago in ancient Egypt, where lead compounds were applied as foundation or eye makeup. A hair-dye recipe first described in Greco-Roman times involves applying a paste of lead oxide and calcium hydroxide, or lime, to graying and fair locks.
As in the famed Grecian Formula--also a lead-based recipe--repeated applications darken the hair as much as desired. Researchers knew the lead-lime mix reacts with sulfur present in hair's keratin proteins to form crystals of lead sulfide, also called galena.
To figure out just how tiny and penetrating those galena crystals are, a team of investigators from the Center for Research and Restoration of the Museums of France (C2RMF), L'Oreal Research and Argonne National Laboratory soaked blond hairs in a solution of the Greco-Roman chemicals for up to three days.
Once the strands were sufficiently darkened the team examined them under a special electron microscope capable of imaging thin sections from a relatively thick sample. They saw that the strands were shot through with lead-sulfide crystals averaging 4.8 nanometers in size--about the same as the so-called quantum dots studied by researchers today. The crystals formed strings down the length of the hair fiber.
Judging from the spacing of these strings and chemical changes to the hair, the crystals apparently grow among the sulfur-rich amino acids that surround the hair's keratin microfibers.
"It is remarkable that the composition and supramolecular organization of keratins can control PbS [lead-sulfide] nanocrystal growth inside a hair," the group writes.
Philippe Walter of the C2RMF, lead author of the report, says he has not studied what happens to hair dyed with Grecian Formula, but he suspects nanocrystals are also at work.
Such lead-based dyes don't seem to be harmful, he notes, because they have trouble penetrating the skin."
*image below*
http://www.sciam.com/media/inline/000C8282-7847-151D-B84783414B7F0000_1.gif
GRECIAN FORMULA: Cross sections of hair strands taken by optical (top) and fluorescence (bottom) imaging reveal that hair exposed longer to an ancient hair-dye recipe (right) exhibit greater penetration by nanometer-scale crystals deep inside the strands, compared with those exposed briefly (left).
PHILIPPE WALTER | |
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| Nanotechnology and The Little Old Man
Posted: 6/26/2008 5:31:51 PM | Hi
I wonder how many nano seconds it takes for lead-lime mix to react with sulfur, also to form crystals!
Notes a) nanosecond; A nanosecond (ns) is one billionth of a second.
* shorter times
* 1.0 nanoseconds (1.0 ns) – cycle time for frequency 1 GHz, radio wavelength 0.3 m
* 1.02 nanoseconds (approximately) – time taken for light to travel 1 foot.
* 3.33564095 nanoseconds (approximately) – time taken for light to travel 1 metre
* longer times
By 2005, microprocessors could execute a singular instruction in 1 nanosecond.
Indeed, a common computer instruction is 'nanosleep' meaning suspend execution for a length of time given in nanoseconds (for example,
["Greco-Roman chemicals"]
Very Interesting!!
["amino acids"]
Below is a link to "THE PROTEIN BANK"
http://www.rcsb.org/pdb/results/results.do | |
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| Nanotechnology and The Little Old Man
Posted: 6/26/2008 10:37:36 PM | http://www.rcsb.org/pdb/results/results.do
A portion of the page could not be displayed!
The error has been logged and will be reviewed by the PDB team.
Please hang up and try your call later | |
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| Nanotechnology and The Little Old Man
Posted: 6/27/2008 7:28:12 AM |
Question; what is the name of at least 1 product, device, field, (it could be of any size),- chemical, drug, etc. that currently uses this technology?
1. nanotube socks | |
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| Nanotechnology and The Little Old Man
Posted: 6/27/2008 8:33:37 AM |
By 2005, microprocessors could execute a singular instruction in 1 nanosecond
Actually it was sooner than that. Most GPU technology in the last 10 years has executed single instructions on a scale of nanoseconds, it depends on which instruction you are talking about however since some instructions can take several ticks to perform. | |
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| Nanotechnology and The Little Old Man
Posted: 6/27/2008 8:55:01 AM |
Question; what is the name of at least 1 product, device, field, (it could be of any size),- chemical, drug, etc. that currently uses this technology?
OLED (Organic Light Emitting Diodes), are being used by many display producers to create cheaper, energy efficient, and durable, screens with much much higher definition than any other diode based display technology on the market today. You may have a TV, Car Stereo, Microwave, Cell Phone, MP3 Player, Computer Monitor, or VCR/DVD Player in your house right now that uses the technology. Sony has used it since 2004, Samsung since 2005, not sure on other companies. The OLED technology was made possible by nano-technology research and application. You can hit a OLED display with a high amount of force and only have a short term blurring occur in the image, instead of a permanent outline of the object it was hit with that LCDs incur when hit.
Graphene is a technology being developed based on research and application of OLEDs which will produce high definition display technology on a scale that we don't currently have measurements for (a pixel being nothing more than an atom wide). | |
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