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1、纳米材料（Nanometer material）brief introductionFrom the size, usually produce significant changes in physical and chemical properties of fine particles in the size of 0.1 microns (1 m = 100 cm, 1 cm = 10000 micron, 1 micron = 1000 nm, 1 nm = 10 angstroms), 100 nm. Therefore, particles with a particle siz
2、e of 1100 nm are called ultrafine particles, and they are also nano materials. Nano metal materials were developed in the middle of 1980s, and later came out with nano semiconductor films, nano ceramics, nano porcelain materials and nano biomedical materials. Nano structured materials, referred to a
3、s material (nano), refers to the size of their structural units between 1 nm and 100 nm range. Because its size is close to the coherence length of electrons, its properties change greatly because of the self-organization caused by strong coherence. Also, the scale is close to the wavelength of ligh
4、t, it has special effect of the surface, so its performance characteristics, such as melting point, magnetic, optical, thermal, electrical conductivity and so on, are often different in nature of the substance in the overall state of the. Nano particle materials, also known as ultrafine particles, a
5、re composed of nanoparticles (nano, particle). Nanoparticles also called ultrafine particles, generally refers to the particles in the 1 100nm between the size of the transition region is at the junction of atomic clusters and macroscopic objects, usually from on microscopic and macroscopic point of
6、 view, macro system micro system the system is not only the atypical atypical, is a typical mesoscopic system, it with surface effect, small size effect and macroscopic quantum tunneling effect. When people will be subdivided into macroscopic objects of ultrafine particles (nano), it will show many
7、unique properties, it is compared with the optical, thermal, electrical, magnetic, mechanical and chemical properties and bulk solids have significantly different will. The broad range of nanotechnology can include nano material technology and nano processing technology, nano measurement technology,
8、 nano application technology and so on. The nano technology focuses on nano functional material production (superfine powder, coating, nano modified materials etc.), performance testing technology (chemical composition, microstructure, surface morphology, physical and chemical, electrical, magnetic,
9、 thermal and optical properties). Nanofabrication technology includes precise machining technology (energy beam machining) and scanning probe technique. Nano materials have unique properties, when the material of small scale to a certain extent, it must use quantum mechanics to replace the tradition
10、al mechanical view to describe its behavior, when the powder particle size from 10 micron to 10 nm, the diameter is changed to 1000 times, but converted into volume will be 10 the power of 9 times, so the two act will produce significant differences. The reason that nanoparticles differ from bulk ma
11、terial is that its surface area is relatively large, that is, the surface of ultrafine particles is covered with a ladder like structure, which represents unstable atoms with high surface energy. These atoms are very easy to bond with foreign atoms and provide large surface active atoms because of t
12、heir reduced size. On the melting point, the powders because each particle composed of atoms, the surface atoms are in the unstable state, so that the surface lattice vibration amplitude is large, so it has high surface energy, heat caused by the special properties of ultrafine particles, which is c
13、aused by the melting point decreased with nano powder than traditional powder in a relatively easy low temperature sintering, and become a good sintering promoting material. The common magnetic material are more magnetic area aggregate, when the particle size as small as the area cannot separate mag
14、netic zone is formed of single domain magnetic material. Therefore, when the magnetic material is made into ultrafine particles or films, it will become an excellent magnetic material. The particle size of nanoparticles (10 nm to 100 nm) is smaller than the length of light wave, so it will interact
15、with incident light very complex. Metal in the appropriate evaporation deposition conditions, can be easily absorbed light of black metal ultrafine particles, known as metal black,This contrasts strongly with the high reflectivity surface of the metal in the vacuum coating. Nanomaterials can be used
16、 in infrared sensor materials because of their high light absorptivity. Nanotechnology is still in its infancy in countries all over the world. Although a few countries, such as the United States, Japan and Germany, have begun to take shape, they are still under study. The emergence of new theories and technologies is still in the ascendant. Our country has made great efforts to catch up with the advanced countries, and the research team is also growing. 1Edit the discovery of
