What is the nanotechnology ? What is a nanotechnology used for ?



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Nanotechnology
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Nanotechnology

Plan:


  1. What is the nanotechnology ?

  2. What is a nanotechnology used for ?

  3. Is nanotechnology harmful ?


Nanotechnology, also shortened to nanotech, is the use of matter on an atomicmolecular, and supramlecular scale for industrial purposes. The earliest, widespread description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macroscale products, also now referred to as molecular nanotechnology. A more generalized description of nanotechnology was subsequently established by the National Nanotechnology Initiative, which defined nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers. This definition reflects the fact that quantum mechanical effects are important at this quantum-realm scale, and so the definition shifted from a particular technological goal to a research category inclusive of all types of research and technologies that deal with the special properties of matter which occur below the given size threshold. It is therefore common to see the plural form "nanotechnologies" as well as "nanoscale technologies" to refer to the broad range of research and applications whose common trait is size. Nanotechnology as defined by size is naturally broad, including fields of science as diverse as surface science, organic chemistry, molecular biology, semiconductor physics, energy storage, engineering, microfabrication, and molecular engineering. The associated research and applications are equally 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 direct control of matter on the atomic scale.

History of Nanotechnology:
The concepts that seeded nanotechnology were first discussed in 1959 by renowned physicist Richard Feynman in his talk There's Plenty of Room at the Bottom, in which he described the possibility of synthesis via direct manipulation of atoms. The term "nano-technology" was first used by Norio Taniguchi in 1974, though it was not widely known. Inspired by Feynman's concepts, K. Eric Drexler used the term "nanotechnology" in his 1986 book Engines of Creation: The Coming Era of Nanotechnology, which proposed the idea of a nanoscale "assembler" which would be able to build a copy of itself and of other items of arbitrary complexity with atomic control. Also in 1986, Drexler co-founded The Foresight Institute (with which he is no longer affiliated) to help increase public awareness and understanding of nanotechnology concepts and implications.
The emergence of nanotechnology as a field in the 1980s occurred through convergence of Drexler's theoretical and public work, which developed and popularized a conceptual framework for nanotechnology, and high-visibility experimental advances that drew additional wide-scale attention to the prospects of atomic control of matter. In the 1980s, two major breakthroughs sparked the growth of nanotechnology in the modern era. First, the invention of the scanning tunneling microscope in 1981 which provided unprecedented visualization of individual atoms and bonds, and was successfully used to manipulate individual atoms in 1989. The microscope's developers Gerd Binnig and Heinrich Rohrer at IBM Zurich Research Laboratory received a Nobel Prize in Physics in 1986. Binnig, Quate and Gerber also invented the analogous atomic force microscope that year.


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.
Second, fullerenes were discovered in 1985 by Harry Kroto, Richard Smalley, and Robert Curl, who together won the 1996 Nobel Prize in Chemistry. C60 was not initially described as nanotechnology; the term was used regarding subsequent work with related carbon nanotubes which suggested potential applications for nanoscale electronics and devices. The discovery of carbon nanotubes is largely attributed to Sumio Iijima of NEC in 1991, for which Iijima won the inaugural 2008 Kavli Prize in Nanoscience.
A nanolayer-base metal–semiconductor junction transistor was initially proposed by A. Rose in 1960, and fabricated by L. Geppert, Mohamed Atalla and Dawon Kahng in 1962. Decades later, advances in multi-gate technology enabled the scaling of metal–oxide–semiconductor field-effect transistor devices down to nano-scale levels smaller than 20 nm gate length, starting with the FinFET (fin field-effect transistor), a three-dimensional, non-planar, double-gate MOSFET. At UC Berkeley, a team of researchers including Digh Hisamoto, Chenming Hu, Tsu-Jae King Liu, Jeffrey Bokor and others fabricated FinFET devices down to a 17 nm process in 1998, then 15 nm in 2001, and then 10 nm in 2002.
In the early 2000s, the field garnered increased scientific, political, and commercial attention that led to both controversy and progress. Controversies emerged regarding the definitions and potential implications of nanotechnologies, exemplified by the Royal Society's report on nanotechnology. Challenges were raised regarding the feasibility of applications envisioned by advocates of molecular nanotechnology, which culminated in a public debate between Drexler and Smalley in 2001 and 2003.
Meanwhile, commercialization of products based on advancements in nanoscale technologies began emerging. These products are limited to bulk applications of nanomaterials and do not involve atomic control of matter. Some examples include the Silver Nano platform for using silver nanoparticles as an antibacterial agent, nanoparticle-based transparent sunscreens, carbon fiber strengthening using silica nanoparticles, and carbon nanotubes for stain-resistant textiles.
Governments moved to promote and fund research into nanotechnology, such as in the U.S. with the National Nanotechnology Initiative, which formalized a size-based definition of nanotechnology and established funding for research on the nanoscale, and in Europe via the European Framework Programmes for Research and Technological Development.
By the mid-2000s new and serious scientific attention began to flourish. Projects emerged to produce nanotechnology roadmaps which center on atomically precise manipulation of matter and discuss existing and projected capabilities, goals, and applications.
In 2006, a team of Korean researchers from the Korea Advanced Institute of Science and Technology (KAIST) and the National Nano Fab Center developed a 3 nm MOSFET, the world's smallest nanoelectronic device. It was based on gate-all-around (GAA) FinFET technology.
Over sixty countries created nanotechnology research and development (R&D) government programs between 2001 and 2004. Government funding was exceeded by corporate spending on nanotechnology R&D, with most of the funding coming from corporations based in the United States, Japan and Germany.




What is a nanotechnology used for?
Nanotechnology is helping to considerably improve, even revolutionize, many technology and industry sectors: information technology, homeland security, medicine, transportation, energy, food safety, and environmental science, among many others. Described below is a sampling of the rapidly growing list of benefits and applications of nanotechnology.
Many benefits of nanotechnology depend on the fact that it is possible to tailor the structures of materials at extremely small scales to achieve specific properties, thus greatly extending the materials science toolkit. Using nanotechnology, materials can effectively be made stronger, lighter, more durable, more reactive, more sieve-like, or better electrical conductors, among many other traits. Many everyday commercial products are currently on the market and in daily use that rely on nanoscale materials and processes:

  • Nanoscale additives to or surface treatments of fabrics can provide lightweight ballistic energy deflection in personal body armor, or can help them resist wrinkling, staining, and bacterial growth.

  • Clear nanoscale films on eyeglasses, computer and camera displays, windows, and other surfaces can make them water- and residue-repellent, antireflective, self-cleaning, resistant to ultraviolet or infrared light, antifog, antimicrobial, scratch-resistant, or electrically conductive.

  • Nanoscale materials are beginning to enable washable, durable “smart fabrics” equipped with flexible nanoscale sensors and electronics with capabilities for health monitoring, solar energy capture, and energy harvesting through movement.

  • Lightweighting of cars, trucks, airplanes, boats, and space craft could lead to significant fuel savings. Nanoscale additives in polymer composite materials are being used in baseball bats, tennis rackets, bicycles, motorcycle helmets, automobile parts, luggage, and power tool housings, making them lightweight, stiff, durable, and resilient. Carbon nanotube sheets are now being produced for use in next-generation air vehicles. For example, the combination of light weight and conductivity makes them ideal for applications such as electromagnetic shielding and thermal management. 


Nanotechnology is already broadening the medical tools, knowledge, and therapies currently available to clinicians. Nanomedicine, the application of nanotechnology in medicine, draws on the natural scale of biological phenomena to produce precise solutions for disease prevention, diagnosis, and treatment. Below are some examples of recent advances in this area:


  • ommercial applications have adapted gold nanoparticles as probes for the detection of targeted sequences of nucleic acids, and gold nanoparticles are also being clinically investigated as potential treatments for cancer and other diseases.

  • Better imaging and diagnostic tools enabled by nanotechnology are paving the way for earlier diagnosis, more individualized treatment options, and better therapeutic success rates.

  • Nanotechnology is being studied for both the diagnosis and treatment of atherosclerosis, or the buildup of plaque in arteries. In one technique, researchers created a nanoparticle that mimics the body’s “good” cholesterol, known as HDL (high-density lipoprotein), which helps to shrink plaque. 

  • The design and engineering of advanced solid-state nanopore materials could allow for the development of novel gene sequencing technologies that enable single-molecule detection at low cost and high speed with minimal sample preparation and instrumentation.

  • Nanotechnology researchers are working on a number of different therapeutics where a nanoparticle can encapsulate or otherwise help to deliver medication directly to cancer cells and minimize the risk of damage to healthy tissue. This has the potential to change the way doctors treat cancer and dramatically reduce the toxic effects of chemotherapy.

  • Research in the use of nanotechnology for regenerative medicine spans several application areas, including bone and neural tissue engineering. For instance, novel materials can be engineered to mimic the crystal mineral structure of human bone or used as a restorative resin for dental applications. Researchers are looking for ways to grow complex tissues with the goal of one day growing human organs for transplant. Researchers are also studying ways to use graphene nanoribbons to help repair spinal cord injuries; preliminary research shows that neurons grow well on the conductive graphene surface.


Is nanotechnology harmful ?


Summary
Nanotechnology is often described as an emerging technology-one that not only holds promise for society, but also is capable of revolutionizing our approaches to common problems. Nanotechnology is not a completely new field; however, it is only recently that discoveries in this field have advanced so far as to warrant examination of their impact upon the world around us. The value of nanomaterials in many technology areas is very high because of their versatile properties. As a result, the investment in nanotechnology by the U.S. government has had a very steady growth; in 2004 investment from a range of different federal agencies reached nearly $1 billion, noted Kenneth Olden, National Institute of Environmental Health Sciences. Industrial investment in this area is also growing steadily. Today some nanomaterials are already being used commercially. For example, some companies are using TiO2 nanoparticles in sunscreen lotions because they provide transparency to a sunscreen, and are believed to be less toxic than the organic molecules currently used as UV absorbers in many sunscreen formulations. Nanomaterials can also be found in sporting equipment, clothing, and telecommunication infrastructure. The future of nanotechnology is boundless, according to some speakers. Some of the items that exist today were a topic of science fiction a decade ago and have the potential to transform our society very quickly, said Douglas Mulhall, author of Our Molecular Future.

Nanoparticles fall into three major groups: natural, incidental, and engineered, noted Vicki Colvin, Rice University. Naturally occurring nanomaterials such as volcanic ash, ocean spray, magnetotactic bacteria, mineral composites and others exist in our environment. Incidental nanoparticles, also refered to as waste particles, are produced as a result of some industrial processes. The third category of nanoparticles is engineered nanoparticles-these are the particles associated with nanotechnology. Engineered nanoparticles are subclassified by the type of basic material and/or use: metals, semiconductoris, metal oxides, nanoclays, nanotubules, and quantum dots.
BENEFITS AND POTENTIAL NEGATIVE IMPACT OF NANOTECHNOLOGY
Nanotechnology has direct beneficial applications for medicine and the environment, but like all technologies it may have unintended effects that can adversely impact the environment, both within the human body and within the natural ecosystem. While taking advantage of this new technology for health, environmental, and sustainability benefits, science needs to examine the environmental and health implications. Recently, nanotechnology has received considerable attention from the media. Most of the initial reports have been positive; however, scientists should not forget that not all nanomaterials will be benign, said Kenneth Olden, National Institute of Environmental Health Sciences. Therefore, it is very important to identify the negative aspects of the technology before we introduce it to the marketplace. During the workshop, many speakers and participants spoke of the paucity of data for engineered nanoparticles and cautioned against solely relying on the research of natural and incidential nanoparticles. Determining toxicity can be complicated because not all engineered nanoparticles are more toxic than fine-sized particles of the same chemical composition. The surface coatings of particles, exposure to UV radiation, and dispersion properties can change the behavior of the particles, noted Eva Oberdörster of Southern Methodist University. For example, in pulmonary studies, whether particles aggregate and then disaggregate once they reach the lung fluids as well as the process for generation of nanoparticles, for example, fumed versus precipitated silica seems to be relevant. David Warheit, of the DuPont Company, suggested that developing a working hypothesis for determination of particle toxicity will depend on the capacity of the particles to cause cell and lung injury, promote inflammation, inhibit macrophage function, and persist in the lung. Finally, Warheit observed that species differences complicate research; for example, rats appear to be particularly sensitive to particle-induced pulmonary toxicity.

Some current hypotheses suggest that some engineered nanoparticles may be more toxic than other fine-sized particles of identical chemical composition, noted Warheit. This concept is based primarily on a system evaluation of three particle types: titanium dioxide, carbon black, and diesel particles. However, he noted that the current hypotheses are based on a paucity of data.

GOVERNMENTAL INVOLVEMENT IN ENSURING SAFETY
The potential health and environmental effects of nanoparticles and nanomaterials today raise public concern about nanotechnology. Health and environmental agencies in the United States have the responsibility to provide leadership to ensure the thorough assessment of safety and environmental effects of the new technologies.

Government policy makers need to ensure that nanotechnology is developed as a safe consumer product, said David Rejeski of Woodrow Wilson International Center for Scholars. Because many of the existing governmental regulatory frameworks are 30 to 40 years old-conceived when nanotechnology did not yet exist-they may not be adequate today. Yet, new frameworks have not been proposed.

NIH is working to develop some effective, high output, more informative, and less costly systems and has identified several areas for research in nanomedicine, said William Suk of NIEHS. One of its primary objectives is to obtain a comprehensive database and develop quantitative ways of measuring nanomaterials. The National Institutes of Health defines nanomedicine as the integration between nanotechnology and nanosience. NIH is planning to support research on biological systems and molecules such as proteins, DNA, and RNA and how these molecules interact with each other as well as with environmental agents. The other need that NIH has identified-with the help of about 100 scientists-is to develop the mathematical and analytical tools to interpret measurements. Unfortunately, there are no models and tools yet to quantify the responses in such systems and to interpret what they mean. Thus, mathematicians and chemists need to get involved in the effort to understand the significance of these variations, changes, and readouts in terms of biological processes and subsequent effects on organisms.



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