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Nanotechnology advances affect all branches of engineering and science that deal directly with device components ranging in size between 1/10,000,000 (one ten of a and 1/10,0000 millimeter. At these scales, even the most sophisticated microtechnology-based instrumentation is useless. Engineers anticipate that advances in nanotechnology will allow the direct manipulation of molecules in biological samples (e.g., proteins or paving the way for the development of new materials that have a biological component or that can provide a biological interface. In addition to new tools, nanotechnology programs advance practical understanding of quantum physics. The internalization of quantum concepts is a necessary component of nanotechnology research programs because the laws of classical physics (e.g., classical mechanics or generalized gas laws) do not always apply to the atomic and near-atomic level. Nanotechnology and quantum physics. Quantum theory and mechanics describe the relationship between energy and matter on the atomic and scale. At the beginning of the twentieth century, German physicist Maxwell Planck (1858-1947) proposed that atoms absorb or electromagnetic radiation in bundles of energy termed quanta. This quantum concept seemed counter-intuitive to well-established Newtonian physics. Advancements associated with quantum mechanics (e.g., the uncertainty principle) also had profound implications with regard to the philosophical scientific arguments regarding the limitations of human knowledge. Planck's quantum theory, which also asserted that the energy of light (a was directly proportional to its frequency, proved a powerful concept that accounted for a wide range of physical phenomena. Planck's constant relates the energy of a photon with the frequency of light. Along with the constant for the speed of light, Planck's constant (h = 6.626 x 10−34 Joule-second) is a fundamental constant of nature. Prior to Planck's work, electromagnetic radiation (light) was thought to travel in waves with an infinite number of available frequencies and wavelengths. Planck's work focused on attempting to explain the limited spectrum of light emitted by hot objects. Danish physicist Niels Bohr (1885-1962) studied Planck's quantum theory of radiation and worked in England with physicists J. J. Thomson (1856-1940), and Ernest Rutherford (1871-1937) to improve their classical models of the atom by incorporating quantum theory. During this time, Bohr developed his model of atomic structure. According to the Bohr model, when an electron is excited by energy it jumps from its ground state to an excited state (i.e., a higher energy orbital). The excited atom can then emit energy only in certain (quantized) amounts as its electrons jump back to lower energy orbits located closer to the nucleus. This excess energy is emitted in quanta of electromagnetic radiation (photons of light) that have exactly the same energy as the difference in energy between the orbits jumped by the electron. The electron quantum leaps between orbits proposed by the Bohr model accounted for Plank's observations that atoms emit or absorb electromagnetic radiation in quanta. Bohr's model also explained many important properties of the described by Albert Einstein (1879-1955). Einstein assumed that light was transmitted as a stream of particles termed photons. By extending the well-known wave properties of light to include a treatment of light as a stream of photons, Einstein was able to explain the photoelectric effect. Photoelectric properties are key to regulation of many microtechnology and proposed nanotechnology level systems. Quantum mechanics ultimately replaced electron "orbitals" of earlier atomic models with allowable values for angular momentum (angular velocity by mass) and depicted electron positions in terms of probability "clouds" and regions. In the 1920s, the concept of and its application to physical phenomena was further advanced by more mathematically complex models based on the work of the French physicist Louis Victor de Broglie (1892-1987) and Austrian physicist Erwin Schrödinger (1887-1961) that depicted the particle and wave nature of electrons. De Broglie showed that the electron was not merely a particle but a This proposal led Schrödinger to publish his wave equation in 1926. Schrödinger's work described electrons as a "standing wave" surrounding the nucleus, and his system of quantum mechanics is called wave mechanics. German physicist Max Born (1882-1970) and English physicist P. A. M. Dirac (1902-1984) made further advances in defining the (principally the electron) as a wave rather than as a particle and in reconciling portions of quantum theory with relativity theory. Working at about the same time, German physicist Werner Heisenberg (1901-1976) formulated the first complete and self-consistent theory of quantum mechanics. Matrix mathematics was well established by the 1920s, and applied this powerful tool to quantum mechanics. In 1926, Heisenberg put forward his uncertainty principle which states that two properties of a system, such as position and momentum, can never both be known exactly. This proposition helped cement the dual nature of particles (e.g., light can be described as having both wave and particle characteristics). Electromagnetic radiation (one region of the spectrum that comprises visible light) is now understood to have both particle and wave like properties. In 1925, Austrian-born physicist Wolfgang Pauli (1900-1958) published the Pauli exclusion principle states that no two electrons in an atom can simultaneously occupy the same quantum state (i.e., energy state). Pauli's specification of spin (+1/2 or −1/2) on an electron gave the two electrons in any differing quantum numbers (a system used to describe the quantum state) and made completely understandable the structure of the periodic table in terms of electron configurations (i.e., the energy-related arrangement of electrons in energy shells and suborbitals). In 1931, American chemist Linus Pauling published a paper that used quantum mechanics to explain how two electrons, from two different atoms, are shared to make a between the two atoms. Pauling's work provided the connection needed in order to fully apply the new quantum theory to chemical reactions. Advances in nanotechnology depend upon an understanding and application of these fundamental quantum principles. At the quantum level the smoothness of classical physics disappears and nanotechnologies are predicated on exploiting this quantum roughness. Applications The development of devices that are small, light, self-contained, use little energy and that will replace larger microelectronic equipment is one of the first goals of the anticipated nanotechnology revolution. The second phase will be marked by the introduction of materials not at larger than nanotechnology levels. Given the nature of quantum, scientists that single molecule sensors can be developed and that sophisticated memory storage and neural-like networks can be achieved with a very small number of molecules. Traditional engineering concepts undergo radical transformation at the atomic level. For example, nano-technology motors may drive gears, the cogs of which are composed of the atoms attached to a carbon ring. Nanomotors may themselves be driven by magnetic fields or high precision oscillating lasers. Perhaps the greatest promise for nanotechnology lies in potential advances. Potential nano-level manipulation of DNA offers the opportunity to radically expand the horizons of genomic medicine and Tissue-based biosensors may unobtrusively be able to monitor and regulate site-specific medicine delivery or regulate physiological processes. Nanosystems might serve as highly sensitive detectors of toxic substances or used by inspectors to detect traces of biological or chemical weapons. In electronics and computer science, scientists assert that nanotechnologies will be the next major advance in computing and information processing science. Microelectronic devices rely on recognition and flips in electron gating (e.g. where differential states are ultimately represented by a series of binary numbers ["0" or "1"] that depict voltage states). In contrast, future quantum processing will utilize the identity of quantum states as set forth by quantum numbers. In quantum systems with the ability to encrypted information will rely on precise knowledge of manipulations used to achieve various atomic states. Nanoscale devices are constructed using a combination of fabrication steps. In the initial growth stage, layers of materials are grown on a dimension limiting Layer composition can be altered to control electrical and/or optical characteristics. Techniques such as ( and metallo-organic chemical vapor deposition (MOCVD) are capable of producing layers of a few atoms thickness. The developed pattern is then imposed on successive layers (the pattern transfer stage) to develop desired three dimensional structural characteristics. Nanotechnology Research In the United States, expenditures on nanotechnology development tops $500 million per year and is largely coordinated by the National Science Foundation and Department of Defense Advanced Research Projects Agency (DARPA) under the umbrella of the National Nano-technology Initiative. Other institutions with dedicated funding for nanotechnology include the Department of Energy (DOE) and National Institutes of Health (NIH). Research interests. Current research interests in nano-technology include programs to develop and exploit nanotubes for their ability to provide extremely strong bonds. Nanotubes can be and woven into fibers for use in ultrastrong-but also ultralight-bulletproof vests. Nanotubes are also excellent conductors that can be used to develop precise electronic Other interests include the development of nanotechnology-based sensors that allow smarter autonomous weapons capable of a greater range of adaptations to a target; materials that offer stealth characteristics across a broader span of the electromagnetic spectrum; self-repairing structures; and nanotechnology-based weapons to disrupt-but not destroy-electrical system infrastructure. Further Reading Books Mulhall, Douglas. Our Molecular Future: How Nanotechnology, Robotics, Genetics, and Artificial Intelligence Will Change Our World. Amherst, NY: Prometheus Books, 2002. Periodicals Bennewitz, R., et. al., "Atomic scale memory at a silicon surface." Nanotechnology 13 (2000): 499-502. Electronic National Science and Technology Council. "National Nano-technology Initiative." (March 19, 2003). nanotechnology

Buckminsterfullerene C60, also known as the buckyball, is the simplest of the known as Members of the fullerene family are a major subject of research falling under the nanotechnology umbrella.

Nanotechnology refers broadly to a field of and technology whose unifying theme is the control of matter on the atomic and scale, normally 1 to 100 nanometers, and the fabrication of devices within that size range. It is a highly field, drawing from fields such as,, science,,, and even and Much speculation exists as to what new science and technology may result from these lines of research. Nanotechnology can be seen as an extension of existing sciences into the nanoscale, or as a recasting of existing sciences using a newer, more modern term. Two main approaches are used in nanotechnology. In the "bottom-up" approach, materials and devices are built from components which chemically by principles of 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 colloidal science, coupled with a new generation of analytical tools such as the (AFM), and the (STM). Combined with refined processes such as and, these instruments allow the deliberate manipulation of nanostructures, and led to the observation of novel phenomena. Examples of nanotechnology in modern use are the manufacture of polymers based on molecular structure, and the design of layouts based on surface science. Despite the great promise of numerous nanotechnologies such as and, real commercial applications have mainly used the advantages of colloidal nanoparticles in bulk form, such as,,, and stain resistant clothing.



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nanolithography ! style="BACKGROUND: #e6e6e6; COLOR: #000000" | Nanomaterials | ·



fullerene-chemistry · · · · ! style="BACKGROUND: #e6e6e6; COLOR: #000000" | Molecular nanotechnology |

mechanosynthesis ·


engines-of-creation ----

: Main article: The first use of the distinguishing concepts in 'nanotechnology' (but predating use of that name) was in "," a talk given by physicist at an meeting at on, 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 would become more important, etc. This basic idea appears feasible, and exponential assembly enhances it with to produce a useful quantity of end products. The term "nanotechnology" was defined by Professor in a paper (N. Taniguchi, "On the Basic Concept of 'Nano-Technology'," Proc. Intl. Conf. Prod. Eng. Tokyo, Part II, Japan Society of Precision Engineering, 1974.) 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, who promoted the technological significance of nano-scale phenomena and devices through speeches and the books (1986) and Nanosystems: Molecular Machinery, Manufacturing, and Computation, (1998, ISBN 0-471-57518-6), and so the term acquired its current sense. Nanotechnology and nanoscience got started in the early 1980s with two major developments; the birth of science and the invention of the (STM). This development led to the discovery of in 1986 and a few years later. In another development, the synthesis and properties of semiconductor was studied. This led to a fast increasing number of metal oxide nanoparticles of The was invented five years after the STM was invented. The AFM uses atomic force to see the atoms.

Wikibooks' [[wikibooks:|]] has more about this subject: The Opensource Handbook of Nanoscience and Nanotechnology

One nanometer (nm) is one billionth, or 10-9 of a meter. For comparison, typical carbon-carbon, or the spacing between these atoms in a molecule, are in the range .12-.15 nm, and a double-helix has a diameter around 2 nm. On the other hand, the smallest lifeforms, the bacteria of the genus, are around 200 nm in length. To put that scale in to context the comparative size of a nanometer to a meter is the same as that of a marble to the size of the earth 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 Image:Atomic resolution Au100.JPG‎ Image of on a clean surface, as visualized using The individual composing the surface are visible.

: Main article: A number of physical phenomena become noticeably pronounced as the size of the system decreases. These include effects, as well as effects, for example the " 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 change when compared to macroscopic systems. One example is the increase in surface area to volume of materials. This catalytic activity also opens potential risks in their interaction with Materials reduced to the nanoscale can suddenly show very 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, 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 unique quantum and surface phenomena that matter exhibits at the nanoscale.

: Main article: Modern has reached the point where it is possible to prepare small to almost any structure. These methods are used today to produce a wide variety of useful chemicals such as or commercial This ability raises the question of extending this kind of control to the next-larger level, seeking methods to assemble these single molecules into consisting of many molecules arranged in a well defined manner. These approaches utilize the concepts of and/or to automatically arrange themselves into some useful conformation through a approach. The concept of is especially important: molecules can be designed so that a specific conformation or arrangement is favored due to The Watson-Crick rules are a direct result of this, as is the specificity of an being targeted to a single, or the specific 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, broadly speaking, 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, most notably and interactions. The challenge for nanotechnology is whether these principles can be used to engineer novel constructs in addition to natural ones.

: Main article: 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, a machine that can produce a desired structure or device atom-by-atom using the principles of 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 (who at the time was unaware of an by it referred to a future manufacturing technology based on 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 billions of years of evolutionary feedback can produce sophisticated, optimised biological machines. It is hoped that developments in nanotechnology will make possible their construction by some other means, perhaps using principles. However, Drexler and other researchers 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, is that future nanosystems will be hybrids of silicon technology and biological molecular machines. Yet another view, put forward by the late, is that mechanosynthesis is impossible due to the difficulties in mechanically manipulating individual molecules. This led to an exchange of letters in the publication Chemical & Engineering News in 2003. 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, a molecular actuator, and a nanoelectromechanical relaxation oscillator. An experiment indicating that positional molecular assembly is possible was performed by Ho and Lee at 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.

Space-filling model of the on a surface, using as wheels.

Graphical representation of a, useful as a molecular switch.

This device transfers energy from nano-thin layers of to above them, causing the nanocrystals to emit visible light. [1]

As nanotechnology is a very broad term, there are many disparate but sometimes overlapping subfields that could fall under its umbrella. The following avenues of research could be considered subfields of nanotechnology. This includes subfields which develop or study materials having unique properties arising from their nanoscale dimensions. * science has given rise to many materials which may be useful in nanotechnology, such as and other, and various and * 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. These seek to arrange smaller components into more complex assemblies. * DNA Nanotechnology utilises the specificity of to construct well-defined structures out of and other * More generally, molecular-self-assembly-1 seeks to use concepts of, and in particular, to cause single-molecule components to automatically arrange themselves into some useful conformation. These seek to create smaller devices by using larger ones to direct their assembly. * Many technologies descended from conventional semiconductor-device-fabricationfor fabricating are now capable of creating features smaller than 100 nm, falling under the definition of nanotechnology. hard drives already on the market fit this description, as do (ALD) techniques. and received for their discovery of Giant magnetoresistance and contributions to the field of spintronics in 2007. * Solid-state techniques can also be used to create devices known as nanoelectromechanical-systemsor NEMS, which are related to or MEMS. * tips can be used as a nanoscale "write head" to deposit a chemical on a surface in a desired pattern in a process called dip-pen-nanolithography. This fits into the larger subfield of 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. For an example see * Synthetic chemical methods can also be used to create synthetic-molecular-motors, such as in a so-called |}

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Applications in nanotechnology

What is nano technology how is it used in medical side?

In short nanotechnology is manipulation of matter on atomic or molecular level. Nanotechnology has a large list of applications in medicine. It's use ranges from applications of nanomaterials to nanoelectronic biosensors.

Who discovered nanoscience?

The history of nanotechnology traces the development of the concepts and experimental work falling under the broad category of nanotechnology. Although nanotechnology is a relatively recent development in scientific research, the development of its central concepts happened over a longer period of time. The emergence of nanotechnology in the 1980s was caused by the convergence of experimental advances such as the invention of the scanning tunneling microscope in 1981 and the discovery of fullerenes in 1985, with the elucidation and popularization of a conceptual framework for the goals of nanotechnology beginning with the 1986 publication of the book Engines of Creation. The field was subject to growing public awareness and controversy in the early 2000s, with prominent debates about both its potential implications as well as the feasibility of the applications envisioned by advocates of molecular nanotechnology, and with governments moving to promote and fund research into nanotechnology. The early 2000s also saw the beginnings of commercial applications of nanotechnology, although these were limited to bulk applications of nanomaterials rather than the transformative applications envisioned by the field.

Latest technology in nanotechnology on which you could give paper presentation?

You can give presentation on carbon nano tubes production and its applications OR you can also give presentation on bulletproof jackets enhanced with nanotechnology.

What is the future technology we need to look for?

Many technologies have the potential to greatly influence our future. One example is nanotechnology, the manufacture and use of microscopically small devices. Applications of nanotechnology include communications, medicine, and surveillance.

How is nanotechnology used?

Nanotechnology is currently a wide field of research and applications in fields ranging from biology to semiconductor fabrication. An example in biology is the design and fabrication of extremely small and sensitive chemical sensors. An example in semiconductors is the lithographic creation of IC chips.

How is nanotechnology useful in the field of medicine?

i need some information of nanotechnology and how it is useful in the field of medicine. then what is stem cell nanotechnology and what is the application of stem cell nanotechnology.

When was Nature Nanotechnology created?

Nature Nanotechnology was created in 2006.

Is nanotechnology in use in India?

nanotechnology is high demand in India or in usa.

Is the iPad a nanotechnology?

No, the integrated circuits that make an iPad are not considered nanotechnology.

What role does robotics play in nanotechnology?

Nanotechnology is a bunch of tiny robots.

When was London Centre for Nanotechnology created?

London Centre for Nanotechnology was created in 2003.

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