Nano silver report for this presentation
Liu Canting 20158305009
From this nano materials presentation, there is a lot of knowledge we can learn, especially in aspects of nano silver. Nano silver is a new kind popular stuff applied in physics, biology, information and optoelectronics. In physics, the optical property of nano silver is widely used in stain-glass field because of its absorption spectra exhibiting extinction bands in the visible region which brings beautiful and impressive colors to the glasses. In biology, nano silver is antibacterial and low toxic so that it is broadly used in surgical instruments.
The properties of silver particles are various. For instance, the visible absorption band of gold and silver metal colloids is attributed to surface plasmon oscillation modes of the conduction electrons which are coupled through the surface (roughness) to the external electromagnetic ?eld. Within the framework of Mie theory, which applies to particles much smaller than the wavelength of light, dipole, and higher order transitions can be treated in principle. Nanometer silver broad-spectrum antibacterial Nano-silver particles directly into the bacteria and oxygen metabolism enzyme (-sh) combination, so that the cell suffocation and death of the unique mechanism of action, kill most bacteria, fungi, molds, spores and other microorganisms in contact with them. The eight domestic authorities found that: its resistance to drug-resistant pathogens such as E. coli, drug-resistant Staphylococcus aureus, drug-resistant Pseudomonas aeruginosa, Streptococcus pyogenes, drug-resistant Enterococcus, anaerobic bacteria, such as a comprehensive antimicrobial activity; On the burns and wounds common bacteria such as Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and other g+, g- pathogenic bacteria have bactericidal effect; Chlamydia trachomatis, sexually transmitted diseases caused by Neisseria gonorrhoeae also have a strong bactericidal effect. One antibiotic kills about six pathogens, while nanosilver can kill hundreds of pathogenic microbes. Get rid of bacteria, fungi, trichomoniasis, branch / chlamydia, Neisseria gonorrhoeae, bactericidal effect, antibacterial resistant bacteria have the same killing effect! According to the study, a g can kill more than 650 kinds of bacteria in a matter of minutes. Nano-silver particles and pathogens after the cell wall / membrane, can directly enter the bacteria, and rapidly with the oxygen metabolism of the enzyme thiol (-sh), so that enzyme inactivation, blocking respiratory metabolism asphyxiation and death. Unique sterilization mechanism, making the nano-silver particles in the low concentration can quickly kill pathogens.
As far as I’m concerned , nano silver is dramatically useful in modern high-tech industry, as it is high efficacious, fast acting and tolerance free.
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