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Nanotechnology is receiving a lot of attention of late across the globe. The term nano originates from the Greek, and it means “dwarf.” The term indicates physical dimensions that are in the range of one-billionth (10 -9 ) of a meter.
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Nanotechnology is receiving a lot of attention of late across the globe. The term nano originates from the Greek, and it means “dwarf.” The term indicates physical dimensions that are in the range of one-billionth (10-9) of a meter. This scale is called colloquially nanometer scale, or also nanoscale. One nanometer is approximately the length of two hydrogen atoms. Nanotechnology relates to the design, creation, and utilization of materials whose constituent structures exist at the nanoscale; these constituent structures can, by convention, be up to 100 nm in size.
Nanotechnology allows the design of new materials with desirable properties. They could be biological - as a targeted cure for a specific cancer; or mechanical - to provide great strength; or electronic, - to make much more powerful computers, or environmental – to save energy in lighting, or to increase the effectiveness of catalysts
The term nanotechnology was introduced by Nori Taniguchi in 1974 at the Tokyo International Conference on Production Engineering. He used the word to describe ultrafine machining: the processing of a material to nanoscale precision. This work was focused on studying the mechanisms of machining hard and brittle materials such as quartz crystals, silicon, and alumina ceramics by ultrasonic machining.
Perhaps, the most impressive achievement in nanotechnology was the invention of scanning tunneling microscopy (STM) in 1986 , followed by the explosive development of relative techniques, such as atomic force microscopy (AFM) , and a dozen different scanning nanoprobe techniques in the subsequent 10 to 15 years. The fact that the Nobel prize for the invention of STM was given to Gerd Binning and Heinrich Rohrer in 1986, only 4 years after the first publication, highlights the extreme importance of this method. For the first time in history (not taking into account quite complicated methods of point-projection field-emission and ion emission microscopy [24]), scientists obtained the instrument enabling them to observe features in atomic and molecular scale, with relative no difficulty. I would say that nanotechnology was launched from there.
The first generation of nanotechnology (late 1990s–early 2000s) focused on performance enhancements to existing micromaterials; the second generation of nanotechnology (slated for 2006–2007) will start employing nanomaterials in much more significant and radical ways. nanotechnology will also allow us to fabricate an entire new generation of products that are cleaner, stronger, lighter, and more precise. [
Nanomaterials with structural features at the nanoscale can be found in the form of clusters, thin films, multilayers, and nanocrystalline materials often expressed by the dimensionality of 0, 1, 2 and 3; the materials of interest include metals, amorphous and crystalline alloys, semiconductors, oxides, nitride and carbide ceramics in the form of clusters, thin films, multilayers, and bulk nanocrystalline materials.
Some other Inanotechnology uses that are already in the marketplace include • Burn and wound dressings • Water filtration • Catalysis • A dental-bonding agent • Coatings for easier cleaning glass • Bumpers and catalytic converters on cars • Protective and glare-reducing coatings for eyeglasses and cars • Sunscreens and powder • Light-weight, stronger tennis racquets • Ink
Nanoguitar – Cornell University • Ten microns (10 x 10-6 m) long, about the size of a red blood cell. • Thickness of a human hair is about 20 times the length of this guitar. • The "strings" (rods of silicon) are 50 nm wide or about 100 atoms across.
Overview of potential applications • < AFM Tip • > Molecular electronics • Transistor • > FED devices: • Displays • < Others • Composites • Biomedical • Catalyst support • Conductive materials • ??? • < Energy storage: • Li-intercalation • Hydrogen storage • Supercaps
Overview of potential applications • < AFM Tip • > Molecular electronics • Transistor • > FED devices: • Displays • < Others • Composites • Biomedical • Catalyst support • Conductive materials • ??? • < Energy storage: • Li-intercalation • Hydrogen storage • Supercaps
Field Emitting Devices Single Emitter Film Emitter
Energy Storage Experiments & Modelling • Electrochemical Storage of Lithium • Electrochemical Storage of Hydrogen • Gas Phase Intercalation of Hydrogen • Supercapacitors
Molecular electronics • FEDs • CNTFETs • SETs
Patterned Film Field Emitters • Etching and lithography • Conventional CVD • Soft lithography
Smallest object ever created by humans • was sculpted by two laser beams focused across resin. The resin solidified only where the lasers crossed. • Created by a team of researchers at Osaka University in Japan, the bull measures 10 microns from horns to tail, and seven microns across (1 micron = 1000 nm).
Health Issues • Makes nanoparticles useful for delivering much-needed drugs • But they might also deliver toxins.
Environmental Studies • Studying how nano-structured membranes could screen pesticides and harmful bacteria from water supplies. • Other scientists are developing low-cost, nano-scale iron hydroxide granules to remove arsenic from drinking water. • Still others have suggested that nano-sized sensors could help detect pollutants or monitor and correct changes in the ozone layer.
Some Areas of Focus Energy Disease Treatment Medications Manufacturing Plastics Electronics Organ Growth Nanotechnology Transportation Ceramics Weapons Sensors Textiles Epoxies Metals Waste Surgery
The Vision • In the next 50 years, machines will get increasingly smaller--so small that thousands of these tiny machines would fit into the period at the end of this sentence.
The Vision • Within a few decades, we will use these nanomachines to manufacture consumer goods at the molecular level… • Make baseballs, telephones, cars, etc. in the same company