Nanoparticles of silver

CuNPs) in Fig. 7 shows the monodisperse and uniformly distributed spherical particles of 10+5 nm diameter. The solution containing nanoparticles of silver was found to be transparent and stable for 6 months with no significant change in the surface plasmon and average particle size. However, in the absence of starch, the nanoparticles formed were observed to be immediately aggregated into black precipitate. The hydroxyl groups of the starch polymer act as passivation contacts for the stabilization of the metallic nanoparticles in the aqueous solution. The method can be extended for synthesis of various other metallic and bimetallic particles as well. 

For instance, nanoparticles of silver chloride have been synthesized by mixing two mi-croemnlsions, one containing silver ions and the other containing chloride ions. It was shown that the average particle size, the polydispersity and the number of particles formed depend on the intermicellar exchange rate and/or the rigidity of the surfactant shell [228],... 

Fig. 6.2). TEM observations for the as-prepared, silver nanoparticles showed that the nanoparticles of silver were ca.15 nm in size (Fig. 6.3). 

Pillai V, Kumar P, Hou M J, Ayyub P, Shah DO (1995) Preparation of Nanoparticles of Silver-Halides, Superconductors and Magnetic-Materials Using Water-in-Oil Microemulsions as Nano-Reactors. Adv Colloid Interface Sci 55 241-269... 

Properties of the metal particles under study depends on the synthesis conditions such as availability of stabilizing medium, its composition, the type of reducer and temperature. Nanosized metal particles possess lyophobic properties. We have established a possibility to use the arabinogalactan polysaccharide for their stabilization in the aqueous medium. It efficiently reduces and stabilizes nanoparticles of silver and other noble metals. 11 is expected also that the stabilizer controls the electronic characteristics of metal nanoparticles. Our results below have confirmed this assumption. 

Shankar et al. [24] reported on the synthesis of pure metallic nanoparticles of silver and gold by the reduction of Ag+ and Au + ions using neem (Azadirachta indica)... 

Can embedding nanoparticles of silver into a polymer give the polymer antimicrobial properties Researchers tested the antimicrobial properties of a new composite material- the polymer poly(4-vinyl-N-hexylpyridinium bromide), known as NPVP, which attracts cations. It is known that silver ions from silver bromide and silver nitrate exhibit antimicrobial activity. Silver bromide was embedded into the NPVP polymer. Scientists tested the antimicrobial properties of the composite material. Their results, illustrated in the graph, show the growth of E. coli bacteria over a period of approximately four hours. Each line represents the E. coli population in response to the introduction of a particular substance. 

Nanoparticles of silver and carbon are also being studied as replacements for copper or gold plating or for copper filling of microvias in interconnect substrates. ... 

Rillai, V., Kumar, R, Hou, M.J., Ayyub, R, and Shah, D.O., Preparation of nanoparticles of silver halides, superconductors and magnetic materials using water-in-oil microemulsions as nano-reactors, Adv. Colloid Interface Sci., 55, 241, 1995. 

Figure 2. FTIR spectra 1 — initial MCM-41 siUca, 2 - MCM-41 with grafted =SiH groups, 3 - MCM-41 with reduced nanoparticles of silver and gold right).

Figure 3. XRD patterns of 1 — initial MCM-41 silica, 2 — modified with triethoxysilane MCM-H, 3 — MCM-41 with incorporated nanoparticles of silver.

In the present review, we describe the effects of different silver nanostructures that were prepared by various methods in our laboratories on the emission intensity of fluorophores with various quantum yields and on biochemical fluorophores. The silver nanostructures consist of subwavelength size nanoparticles of silver deposited on inert substrates. These particles display a surface plasmon absorption, which in the small... 

Wilkinson LJ, White RJ, Chapman JK. Silver and nanoparticles of silver in wound dressings a review of efficacy and safety. J Wound Care 201 l 20(ll) 543-9. 

Effect of nanoparticles of silver and gold on gas exchange and heat production of chicken embryos... 

The results suggest that nanoparticles of silver increased rate of metabolism of chicken during embryonic development, however, more research should be done to elucidate the mode of aetion of nano Ag. 

The result implies that nanoparticles of silver did not affect energy metabolism and did not stimulate nor depress growth of chicken. However, it has to be kept in mind that the present results included only two weeks of measurements and so far may have only preliminary character. 

Sawosz, E., M. Grodzik, M. Zielinska, T. Niemiec, B. Olszanska and A. Chwalibog, 2009. Nanoparticles of silver do not affect growth, development and DNAoxidative damage in chicken embryos. Arch. Geflugelk. 73 208-213. SAS Institute Inc., 2009. SAS Procedure Guide. Version 9.2. SAS Institute Inc., Cary, NC, USA. 

Although, fungi have been shown to produce metallic nanoparticles of silver, gold and platinum [7], the majority of studies in this area have focused on the synthesis... 

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