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دانشگاه فنی انقلاب اسلامی تهران - Nanotechnology
وبلاگ صنایع شیمیایی

Nanotechnology (sometimes shortened to "nanotech") is the study of manipulating
matter on an atomic and molecular scale. Generally, nanotechnology deals with
structures sized between 1 to 100 nanometre in at least one dimension, and
involves developing materials or devices possessing at least one dimension
within that size. Quantum mechanical effects are very important at this scale,
which is in the quantum realm.
Nanotechnology is very diverse, ranging from extensions of conventional device
physics to completely new approaches based upon molecular self-assembly, from
developing new materials with dimensions on the nanoscale to investigating
whether we can directly control matter on the atomic scale.
There is much debate on the future implications of nanotechnology.
Nanotechnology may be able to create many new materials and devices with a vast
range of applications, such as in medicine, electronics, biomaterials and energy
production. On the other hand, nanotechnology raises many of the same issues as
any new technology, including concerns about the toxicity and environmental
impact of nanomaterials,[1] and their potential effects on global economics, as
well as speculation about various doomsday scenarios. These concerns have led to
a debate among advocacy groups and governments on whether special regulation of
nanotechnology is warranted.
   Contents
    1 Origins
    2 Fundamental concepts
     2.1 Larger to smaller: a materials perspective
     2.2 Simple to complex: a molecular perspective
     2.3 Molecular nanotechnology: a long-term view
    3 Current research
     3.1 Nanomaterials
     3.2 Bottom-up approaches
     3.3 Top-down approaches
     3.4 Functional approaches
     3.5 Biomimetic approaches
     3.6 Speculative
    4 Tools and techniques
    5 Applications
    6 Implications
     6.1 Health and environmental concerns
     6.2 Regulation
    7 See also
    8 References
    9 Further reading
    10 External links

 Origins
 

Buckminsterfullerene C60, also known as the buckyball, is a representative
member 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 found in 'nano-technology' (but pre-dating 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 California
Institute of Technology (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, and 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 increasingly more significant, etc.
This basic idea appeared plausible, and exponential assembly enhances it with
parallelism to produce a useful quantity of end products. The term
"nanotechnology" was defined by Tokyo University of Science Professor Norio
Taniguchi in a 1974 paper[2] 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,[3] and so the
term acquired its current sense. Engines of Creation 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 1985 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 and
metal oxide nanoparticles and quantum dots. The atomic force microscope (AFM or
SFM) 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 and is evaluated by the President's
Council of Advisors on Science and Technology.
  Fundamental concepts
Nanotechnology is the engineering of functional systems at the molecular scale.
This covers both current work and concepts that are more advanced. In its
original sense, nanotechnology refers to the projected ability to construct
items from the bottom up, using techniques and tools being developed today to
make complete, high performance products.
One nanometer (nm) is one billionth, or 10−9, of a meter. By comparison, 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 life-forms, the bacteria of the
genus Mycoplasma, are around 200 nm in length. By convention, nanotechnology is
taken as the scale range 1 to 100 nm following the definition used by the
National Nanotechnology Initiative in the US. The lower limit is set by the size
of atoms (hydrogen has the smallest atoms, which are approximately a quarter of
a nm diameter) since nanotechnology must build its devices from atoms and
molecules. The upper limit is more or less arbitrary but is around the size that
phenomena not observed in larger structures start to become apparent and can be
made use of in the nano device.[4] These new phenomena make nanotechnology
distinct from devices which are merely miniaturised versions of an equivalent
macroscopic device; such devices are on a larger scale and come under the
description of microtechnology.[5]
To put that scale in another context, the comparative size of a nanometer to a
meter is the same as that of a marble to the size of the earth.[6] Or another
way of putting it: a nanometer is the amount an average man's beard grows in the
time it takes him to raise the razor to his face.[6]
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.[7]
Areas of physics such as nanoelectronics, nanomechanics, nanophotonics and
nanoionics have evolved during the last few decades to provide a basic
scientific foundation of nanotechnology.
  Larger to smaller: a materials perspective
 

Image of reconstruction on a clean Gold(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,
quantum effects become dominant when the nanometer size range is reached,
typically at distances of 100 nanometers or less, the so called quantum realm.
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. Diffusion and reactions at nanoscale,
nanostructures materials and nanodevices with fast ion transport are generally
referred to nanoionics. 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.[8]
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); insoluble materials become soluble (gold). 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.[9]
  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
manufacture 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
configuration 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 capable of producing devices in parallel and
be 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 new constructs in addition to natural ones.
  Molecular nanotechnology: a long-term view
Main article: Molecular nanotechnology
Molecular nanotechnology, sometimes called molecular manufacturing, describes
engineered nanosystems (nanoscale machines) operating on the molecular scale.
Molecular nanotechnology is especially associated with the 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[10] 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.[11] The physics and engineering
performance of exemplar designs were analyzed in Drexler's book Nanosystems.
In general it is very difficult to assemble devices on the atomic scale, as all
one has to position atoms on other atoms of comparable size and stickiness.
Another view, put forth by Carlo Montemagno,[12] 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.[13] 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,[14] and a nanoelectromechanical relaxation oscillator.[15]
See nanotube nanomotor for more examples.
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
 

Graphical representation of a rotaxane, useful as a molecular switch.
 

This DNA tetrahedron[16] is an artificially designed nanostructure of the type
made in the field of DNA nanotechnology. Each edge of the tetrahedron is a 20
base pair DNA double helix, and each vertex is a three-arm junction.
 

This device transfers energy from nano-thin layers of quantum wells to
nanocrystals above them, causing the nanocrystals to emit visible light.[17]
  Nanomaterials
The nanomaterials field includes subfields which develop or study materials
having unique properties arising from their nanoscale dimensions.[18]
 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. Nanomaterials with fast ion transport are
 related also to nanoionics and nanoelectronics.
 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.
 Nanoscale materials are sometimes used in solar cells which combats the cost
 of traditional Silicon solar cells
 Development of applications incorporating semiconductor nanoparticles to be
 used in the next generation of products, such as display technology, lighting,
 solar cells and biological imaging; see quantum dots.
  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[19]).
 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.
 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 technique fits into the larger subfield of
 nanolithography.
  Top-down approaches
These seek to create smaller devices by using larger ones to direct their
assembly.
 Many technologies that 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,[20] as do atomic layer deposition (ALD) techniques. Peter
 Grünberg and Albert Fert received the Nobel Prize in Physics in 2007 for their
 discovery of Giant magnetoresistance and contributions to the field of
 spintronics.[21]
 Solid-state techniques can also be used to create devices known as
 nanoelectromechanical systems or NEMS, which are related to
 microelectromechanical systems or MEMS.
 Focused ion beams can directly remove material, or even deposit material when
 suitable pre-cursor gasses are applied at the same time. For example, this
 technique is used routinely to create sub-100 nm sections of material for
 analysis in Transmission electron microscopy.
 Atomic force microscope tips can be used as a nanoscale "write head" to
 deposit a resist, which is then followed by an etching process to remove
 material in a top-down method.
  Functional approaches
These seek to develop components of a desired functionality without regard to
how they might be assembled.
 Molecular scale electronics seeks to develop molecules with useful electronic
 properties. These could then be used as single-molecule components in a
 nanoelectronic device.[22] For an example see rotaxane.
 Synthetic chemical methods can also be used to create synthetic molecular
 motors, such as in a so-called nanocar.
  Biomimetic approaches
 Bionics or biomimicry seeks to apply biological methods and systems found in
 nature, to the study and design of engineering systems and modern technology.
 Biomineralization is one example of the systems studied.
 Bionanotechnology is the use of biomolecules for applications in
 nanotechnology, including use of viruses.[23]
  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,[24][25][26] but it may not be easy to do such a thing because of
 several drawbacks of such devices.[27] 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 concepts.[28][29]
 Productive nanosystems are "systems of nanosystems" which will be complex
 nanosystems that produce atomically precise parts for other nanosystems, not
 necessarily using novel nanoscale-emergent properties, but well-understood
 fundamentals of manufacturing. Because of the discrete (i.e. atomic) nature of
 matter and the possibility of exponential growth, this stage is seen as the
 basis of another industrial revolution. Mihail Roco, one of the architects of
 the USA's National Nanotechnology Initiative, has proposed four states of
 nanotechnology that seem to parallel the technical progress of the Industrial
 Revolution, progressing from passive nanostructures to active nanodevices to
 complex nanomachines and ultimately to productive nanosystems.[30]
 Programmable matter seeks to design materials whose properties can be easily,
 reversibly and externally controlled though a fusion of information science
 and materials science.
 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.
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.[31] However, this is still a slow process because of low scanning velocity
of the microscope. Various techniques of nanolithography such as optical
lithography, X-ray lithography 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.
Another 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.
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.[31] 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. Dual polarisation interferometry is one
tool suitable for characterisation of self assembled thin films. 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.
However, new therapeutic products, based on responsive nanomaterials, such as
the ultradeformable, stress-sensitive Transfersome vesicles, are under
development and already approved for human use in some countries.[citation
needed]
  Applications
Main article: List of nanotechnology applications
As of August 21, 2008, the Project on Emerging Nanotechnologies estimates that
over 800 manufacturer-identified nanotech products are publicly available, with
new ones hitting the market at a pace of 3–4 per week.[32] The project lists all
of the products in a publicly accessible online.[33] Most applications are
limited to the use of "first generation" passive nanomaterials which includes
titanium dioxide in sunscreen, cosmetics and some food products; Carbon
allotropes used to produce gecko tape; 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.[34]
 

One of the major applications of nanotechnology is in the area of
nanoelectronics with MOSFET's being made of small nanowires ~10 nm in length.
Here is a simulation of such a nanowire.
The National Science Foundation (a major distributor for nanotechnology research
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.[35] This study 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. According to Berube, 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.[36]
  Implications
Main article: Implications of nanotechnology
Because of 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.
There are possible dangers that arise with the development of nanotechnology.
The Center for Responsible Nanotechnology suggests that new developments could
result, among other things, in untraceable weapons of mass destruction,
networked cameras for use by the government, and weapons developments fast
enough to destabilize arms races ("Nanotechnology Basics").
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[37] that successful
commercialization depends on adequate oversight, risk research strategy, and
public engagement. Berkeley, California is currently the only city in the United
States to regulate nanotechnology;[38] Cambridge, Massachusetts in 2008
considered enacting a similar law,[39] but ultimately rejected this.[40]
  Health and environmental concerns
Main articles: Health implications of nanotechnology and Environmental
implications of nanotechnology
Some of the recently developed nanoparticle products may have unintended
consequences. Researchers have discovered that silver nanoparticles used in
socks only to reduce foot odor are being released in the wash with possible
negative consequences.[41] Silver nanoparticles, which are bacteriostatic, may
then destroy beneficial bacteria which are important for breaking down organic
matter in waste treatment plants or farms.[42]
A study at the University of Rochester found that when rats breathed in
nanoparticles, the particles settled in the brain and lungs, which led to
significant increases in biomarkers for inflammation and stress response.[43] A
study in China indicated that nanoparticles induce skin aging through oxidative
stress in hairless mice.[44][45]
A two-year study at UCLA's School of Public Health found lab mice consuming
nano-titanium dioxide showed DNA and chromosome damage to a degree "linked to
all the big killers of man, namely cancer, heart disease, neurological disease
and aging".[46]
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."[47] In the absence of specific
nano-regulation forthcoming from governments, Paull and Lyons (2008) have called
for an exclusion of engineered nanoparticles from organic food.[48] A newspaper
article reports that workers in a paint factory developed serious lung disease
and nanoparticles were found in their lungs.[49]
  Regulation
Main article: Regulation of nanotechnology
Calls for tighter regulation of nanotechnology have occurred alongside a growing
debate related to the human health and safety risks associated with
nanotechnology.[50] Furthermore, there is significant debate about who is
responsible for the regulation of nanotechnology. While some non-nanotechnology
specific regulatory agencies currently cover some products and processes (to
varying degrees) – by “bolting on” nanotechnology to existing regulations –
there are clear gaps in these regimes.[51] In "Nanotechnology Oversight: An
Agenda for the Next Administration,"[52] former EPA deputy administrator J.
Clarence (Terry) Davies lays out a clear regulatory roadmap for the next
presidential administration and describes the immediate and longer term steps
necessary to deal with the current shortcomings of nanotechnology oversight.
Stakeholders concerned by the lack of a regulatory framework to assess and
control risks associated with the release of nanoparticles and nanotubes have
drawn parallels with bovine spongiform encephalopathy (‘mad cow’s disease),
thalidomide, genetically modified food,[53] nuclear energy, reproductive
technologies, biotechnology, and asbestosis. Dr. Andrew Maynard, chief science
advisor to the Woodrow Wilson Center’s Project on Emerging Nanotechnologies,
concludes (among others) that there is insufficient funding for human health and
safety research, and as a result there is currently limited understanding of the
human health and safety risks associated with nanotechnology.[54] As a result,
some academics have called for stricter application of the precautionary
principle, with delayed marketing approval, enhanced labelling and additional
safety data development requirements in relation to certain forms of
nanotechnology.[55]
The Royal Society report[56] identified a risk of nanoparticles or nanotubes
being released during disposal, destruction and recycling, and recommended that
“manufacturers of products that fall under extended producer responsibility
regimes such as end-of-life regulations publish procedures outlining how these
materials will be managed to minimize possible human and environmental exposure”
(p.xiii). Reflecting the challenges for ensuring responsible life cycle
regulation, the Institute for Food and Agricultural Standards has proposed
standards for nanotechnology research and development should be integrated
across consumer, worker and environmental standards. They also propose that NGOs
and other citizen groups play a meaningful role in the development of these
standards.
  See also
Main article: Outline of nanotechnology
 Bionanoscience
 Energy applications of nanotechnology
 List of emerging technologies
 List of software for nanostructures modeling
 Materiomics
 Molecular design software
 Molecular mechanics
 Nanoengineering
 Nanobiotechnology
 Nanofluidics
 Nanohub
 Nanometrology
 Nanoscale networks
 Nanotechnology education
 Nanotechnology in water treatment
 Nanothermite
 Nanoweapons
 Top-down and bottom-up
 Translational research
 Wet nanotech
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 ^ N. Taniguchi (1974). On the Basic Concept of 'Nano-Technology. Proc. Intl.
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 ^ Eric Drexler (1991). Nanosystems: Molecular Machinery, Manufacturing, and
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 ^ S.K. Prasad, Modern Concepts in Nanotechnology, pp.31-32, Discovery
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 ^ a b Kahn, Jennifer (2006). "Nanotechnology". National Geographic 2006
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 ^ Rodgers, P. (2006). "Nanoelectronics: Single file". Nature Nanotechnology.
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 ^ Nanotechnology: Developing Molecular Manufacturing
 ^ "Some papers by K. Eric Drexler". http://www.imm.org/PNAS.html.
 ^ California NanoSystems Institute
 ^ C&En: Cover Story - Nanotechnology
 ^ Regan, BC; Aloni, S; Jensen, K; Ritchie, RO; Zettl, A (2005).
 "Nanocrystal-powered nanomotor.". Nano letters 5 (9): 1730–3.
 doi:10.1021/nl0510659. PMID 16159214.
 http://www.physics.berkeley.edu/research/zettl/pdf/312.NanoLett5regan.pdf.
 ^ Regan, B. C.; Aloni, S.; Jensen, K.; Zettl, A. (2005).
 "Surface-tension-driven nanoelectromechanical relaxation oscillator". Applied
 Physics Letters 86: 123119. doi:10.1063/1.1887827.
 http://www.lbl.gov/Science-Articles/Archive/sabl/2005/May/Tiniest-Motor.pdf.
 ^ Goodman, R.P.; Schaap, I.A.T.; Tardin, C.F.; Erben, C.M.; Berry, R.M.;
 Schmidt, C.F.; Turberfield, A.J. (9 December 2005). "Rapid chiral assembly of
 rigid DNA building blocks for molecular nanofabrication". Science 310 (5754):
 1661–1665. doi:10.1126/science.1120367. ISSN 0036-8075. PMID 16339440.
 ^ Wireless nanocrystals efficiently radiate visible light
 ^ Clarkson, AJ; Buckingham, DA; Rogers, AJ; Blackman, AG; Clark, CR (2004).
 "Nanostructured Ceramics in Medical Devices: Applications and Prospects". JOM
 56 (10): 38–43. doi:10.1007/s11837-004-0289-x. PMID 11196953.
 ^ Levins, Christopher G.; Schafmeister, Christian E. (2006). "The Synthesis of
 Curved and Linear Structures from a Minimal Set of Monomers.". ChemInform 37.
 doi:10.1002/chin.200605222.
 ^ "Applications/Products". National Nanotechnology Initiative.
 http://www.nano.gov/html/facts/appsprod.html. Retrieved 2007-10-19.
 ^ "The Nobel Prize in Physics 2007". Nobelprize.org.
 http://nobelprize.org/nobel_prizes/physics/laureates/2007/index.html.
 Retrieved 2007-10-19.
 ^ Das S, Gates AJ, Abdu HA, Rose GS, Picconatto CA, Ellenbogen JC. (2007).
 "Designs for Ultra-Tiny, Special-Purpose Nanoelectronic Circuits". IEEE
 Transactions on Circuits and Systems I 54 (11): 2528–2540.
 doi:10.1109/TCSI.2007.907864.
 ^ C.Michael Hogan. 2010. Virus. Encyclopedia of Earth. National Council for
 Science and the Environment. eds. S.Draggan and C.Cleveland
 ^ Ghalanbor Z, Marashi SA, Ranjbar B (2005). "Nanotechnology helps medicine:
 nanoscale swimmers and their future applications". Med Hypotheses 65 (1):
 198–199. doi:10.1016/j.mehy.2005.01.023. PMID 15893147.
 ^ Kubik T, Bogunia-Kubik K, Sugisaka M. (2005). "Nanotechnology on duty in
 medical applications". Curr Pharm Biotechnol. 6 (1): 17–33. PMID 15727553.
 ^ Leary, SP; Liu, CY; Apuzzo, ML (2006). "Toward the Emergence of
 Nanoneurosurgery: Part III-Nanomedicine: Targeted Nanotherapy, Nanosurgery,
 and Progress Toward the Realization of Nanoneurosurgery". Neurosurgery 58 (6):
 1009–1026. doi:10.1227/01.NEU.0000217016.79256.16. PMID 16723880.
 ^ Shetty RC (2005). "Potential pitfalls of nanotechnology in its applications
 to medicine: immune incompatibility of nanodevices". Med Hypotheses 65 (5):
 998–9. doi:10.1016/j.mehy.2005.05.022. PMID 16023299.
 ^ Cavalcanti A, Shirinzadeh B, Freitas RA Jr., Kretly LC. (2007). "Medical
 Nanorobot Architecture Based on Nanobioelectronics". Recent Patents on
 Nanotechnology. 1 (1): 1–10. doi:10.2174/187221007779814745.
 ^ Boukallel M, Gauthier M, Dauge M, Piat E, Abadie J. (2007). "Smart
 microrobots for mechanical cell characterization and cell convoying". IEEE
 Trans. Biomed. Eng. 54 (8): 1536–40. doi:10.1109/TBME.2007.891171. PMID
 17694877.
 ^ "International Perspective on Government Nanotechnology Funding in 2005".
 http://www.nsf.gov/crssprgm/nano/reports/mcr_05-0526_intpersp_nano.pdf.
 ^ a b R. V. Lapshin (2004). "Feature-oriented scanning methodology for probe
 microscopy and nanotechnology" (PDF). Nanotechnology (UK: IOP) 15 (9):
 1135–1151. doi:10.1088/0957-4484/15/9/006. ISSN 0957-4484.
 http://www.nanoworld.org/homepages/lapshin/publications.htm#feature2004.
 ^ Project on Emerging Nanotechnologies. (2008). Analysis: This is the first
 publicly available on-line inventory of nanotechnology-based consumer
 products.
 ^ Nanotechproject.org
 ^ Applications for Nanotechnology
 ^ Prometheusbooks.com
 ^ Berube, David. Nano=Hype: The Truth Behind the Nanotechnology Buzz, Amherst,
 NY: Prometheus Books, 2006
 ^ Testimony of David Rejeski for U.S. Senate Committee on Commerce, Science
 and Transportation Project on Emerging Nanotechnologies. Retrieved on
 2008-3-7.
 ^ Berkeley considering need for nano safety (Rick DelVecchio, Chronicle Staff
 Writer) Friday, November 24, 2006
 ^ Cambridge considers nanotech curbs - City may mimic Berkeley bylaws (By
 Hiawatha Bray, Boston Globe Staff) January 26, 2007
 ^ Recommendations for a Municipal Health & Safety Policy for Nanomaterials: A
 Report to the Cambridge City Manager. July 2008.
 ^ Lubick, N. (2008). Silver socks have cloudy lining.
 ^ Murray R.G.E., Advances in Bacterial Paracrystalline Surface Layers (Eds.:
 T. J. Beveridge, S. F. Koval). Plenum pp. 3 ± 9. [9]
 ^ Elder, A. (2006). Tiny Inhaled Particles Take Easy Route from Nose to Brain.

 ^ Wu, J; Liu, W; Xue, C; Zhou, S; Lan, F; Bi, L; Xu, H; Yang, X et al. (2009).
 "Toxicity and penetration of TiO2 nanoparticles in hairless mice and porcine
 skin after subchronic dermal exposure.". Toxicology letters 191 (1): 1–8.
 doi:10.1016/j.toxlet.2009.05.020. PMID 19501137.
 ^ Jonaitis, TS; Card, JW; Magnuson, B (2010). "Concerns regarding nano-sized
 titanium dioxide dermal penetration and toxicity study.". Toxicology letters
 192 (2): 268–9. doi:10.1016/j.toxlet.2009.10.007. PMID 19836437.
 ^ Schneider, Andrew, "Amid Nanotech's Dazzling Promise, Health Risks Grow",
 March 24, 2010.
 ^ Weiss, R. (2008). Effects of Nanotubes May Lead to Cancer, Study Says.
 ^ Paull, J. & Lyons, K. (2008). "Nanotechnology: The Next Challenge for
 Organics". Journal of Organic Systems 3: 3–22.
 http://orgprints.org/13569/1/13569.pdf.
 ^ Smith, Rebecca (August 19, 2009). "Nanoparticles used in paint could kill,
 research suggests". London: Telegraph.
 http://www.telegraph.co.uk/health/healthnews/6016639/Nanoparticles-used-in-paint-could-kill-research-suggests.html.
 Retrieved May 19, 2010.
 ^ Kevin Rollins (Nems Mems Works, LLC). "Nanobiotechnology Regulation: A
 Proposal for Self-Regulation with Limited Oversight". Volume 6 - Issue 2.
 http://www.nanolabweb.com/index.cfm/action/main.default.viewArticle/articleID/290/CFID/3564274/CFTOKEN/43473772/index.html.
 Retrieved 2 September 2010.
 ^ Bowman D, and Hodge G (2006). "Nanotechnology: Mapping the Wild Regulatory
 Frontier". Futures 38: 1060–1073. doi:10.1016/j.futures.2006.02.017.
 ^ Davies, JC. (2008). Nanotechnology Oversight: An Agenda for the Next
 Administration.
 ^ Rowe G, Horlick-Jones T, Walls J, Pidgeon N, (2005). "Difficulties in
 evaluating public engagement initiatives: reflections on an evaluation of the
 UK GM Nation?". Public Understanding of Science. 14: 333.
 ^ Maynard, A.Testimony by Dr. Andrew Maynard for the U.S. House Committee on
 Science and Technology. (2008-4-16). Retrieved on 2008-11-24.
 ^ Faunce TA et al. Sunscreen Safety: The Precautionary Principle, The
 Australian Therapeutic Goods Administration and Nanoparticles in Sunscreens
 Nanoethics (2008) 2:231–240 DOI 10.1007/s11569-008-0041-z. Thomas Faunce &
 Katherine Murray & Hitoshi Nasu & Diana Bowman (published online: 24 July
 2008). "Sunscreen Safety: The Precautionary Principle, The Australian
 Therapeutic Goods Administration and Nanoparticles in Sunscreens". Springer
 Science + Business Media B.V.
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 Retrieved 18 June 2009.
 ^ Royal Society and Royal Academy of Engineering (2004). Nanoscience and
 nanotechnologies: opportunities and uncertainties.
 http://www.nanotec.org.uk/finalReport.htm. Retrieved 2008-05-18.
  Further reading
 "Basic Concepts of Nanotechnology" History of Nano-Technology, News,
 Materials, Potential Risks and Important People.
 "About Nanotechnology - An Introduction to Nanotech from The Project on
 Emerging Nanotechnologies". Nanotechproject.org.
 http://www.nanotechproject.org/topics/nano101/. Retrieved 2009-11-24.
 "Nanotechnology Introduction Pages". Nanotech-now.com.
 http://www.nanotech-now.com/nano_intro.htm. Retrieved 2009-11-24.
 Medicalnanotec.com, Introduction to applications of Nanotechnology in
 Medicine.
 Maynard, Andrew, "The Twinkie Guide to Nanotechnology • News Archive •
 Nanotechnology Project". Nanotechproject.org. 2007-10-22.
 http://www.nanotechproject.org/news/archive/the_twinkie_guide_to_nanotechnology/.
 Retrieved 2009-11-24. Woodrow Wilson International Center for Scholars. 2007.
 - "..a friendly, funny, 25-minute travel guide to the technology"
 "Nanotechnology Basics: For Students and Other Learners". Center for
 Responsible Nanotechnology - World Care. 11 November 2008.
 Fritz Allhoff and Patrick Lin (eds.), Nanotechnology & Society: Current and
 Emerging Ethical Issues (Dordrecht: Springer, 2008).
 Fritz Allhoff, Patrick Lin, James Moor, and John Weckert (eds.) "Nanoethics:
 The Ethical and Societal Implications of Nanotechnology". Hoboken: John Wiley
 & Sons. 2007.
 http://www.wiley.com/WileyCDA/WileyTitle/productCd-0470084170.html. "Wiley".
 http://www.nanoethics.org/wiley.html.
 J. Clarence Davies, EPA and Nanotechnology: Oversight for the 21st Century,
 Project on Emerging Nanotechnologies, PEN 9, May 2007.
 Carl Marziali, "Little Big Science," USC Trojan Family Magazine, Winter 2007.
 William Sims Bainbridge: Nanoconvergence: The Unity of Nanoscience,
 Biotechnology, Information Technology and Cognitive Science, June 27, 2007,
 Prentice Hall, ISBN 0-13-244643-X
 Lynn E. Foster: Nanotechnology: Science, Innovation, and Opportunity, December
 21, 2005, Prentice Hall, ISBN 0-13-192756-6
 Impact of Nanotechnology on Biomedical Sciences: Review of Current Concepts on
 Convergence of Nanotechnology With Biology by Herbert Ernest and Rahul Shetty,
 from AZojono, May 2005.
 Hunt, G & Mehta, M (eds)(2008) Nanotechnology: Risk, Ethics & Law, Earthscan,
 London.
 Andrew Schneider, The Nanotech Gamble, Growing Health Risks from Nanomaterials
 in Food and Medicine, First in a Three-Part Series, AOL News Special Report,
 March 24, 2010.
 Hari Singh Nalwa (2004), Encyclopedia of Nanoscience and Nanotechnology
 (10-Volume Set), American Scientific Publishers. ISBN 1-58883-001-2
 Michael Rieth and Wolfram Schommers (2006), Handbook of Theoretical and
 Computational Nanotechnology (10-Volume Set), American Scientific Publishers.
 ISBN 1-58883-042-X
 Akhlesh Lakhtakia (ed) (2004). The Handbook of Nanotechnology. Nanometer
 Structures: Theory, Modeling, and Simulation. SPIE Press, Bellingham, WA, USA.
 ISBN 0-8194-5186-X.
 Fei Wang & Akhlesh Lakhtakia (eds) (2006). Selected Papers on
 Nanotechnology—Theory & Modeling (Milestone Volume 182). SPIE Press,
 Bellingham, WA, USA. ISBN 0-8194-6354-X.
 Jumana Boussey, Georges Kamarinos, Laurent Montès ( ors) (2003), Towards
 Nanotechnology, "Nano et Micro Technologies", Hermes Sciences Publ., Paris,
 ISBN 2-7462-0858-X.
 The Silicon Valley Toxics Coalition (April, 2008), Regulating Emerging
 Technologies in Silicon Valley and Beyond
 Genetic Engineering & Biotechnology News (January, 2008), Getting a Handle on
 Nanobiotech Products Regulators and Companies Are Laying the Groundwork for a
 Predicted Bright Future
 Suh WH, Suslick KS, Stucky GD, Suh YH (2009). "Nanotechnology, nanotoxicology,
 and neuroscience". Progress in Neurobiology 87 (3): 133–70.
 doi:10.1016/j.pneurobio.2008.09.009. PMC 2728462. PMID 18926873.
 http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2728462.
 
 RJ Aitken, SM Hankin, B Ross, CL Tran, V Stone, TF Fernandes, K Donaldson, R
 Duffin, Q Chaudhry, TA Wilkins, SA Wilkins, LS Levy, SA Rocks, A Maynard,
 EMERGNANO Report, Institute of Occupational Medicine, Report TM/09/01 March
 2009.
  External links
 Nanotechnology Dashboard and Resources on Academic Room
 Nanotechnology at the Open Directory Project
   Wikimedia Commons has media related to: Nanotechnology
   Wikibooks has a book on the topic of
   Nanotechnology
   At Wikiversity you can learn more and teach others about Nanotechnology
   at:
   The Department of Nanotechnology

 What is Nanotechnology? (A Vega/BBC/OU Video Discussion).
 Course on Introduction to Nanotechnology
 Nanex Project
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