Chemical silvering

Dewar flasks -chemical silvering of [IHIN FILMS - FILM FORMATION TECHNIQUES] (Vol 23)... 

Silver is another native metal found in museum collections in a variety of forms. Chemically, silver differs gready from gold in that it is highly reactive. Silver occurs in its native state, but is more stable in compounds with other elements. The black tarnish so common on silver items is silver sulfide. Silver objects that have been buried for any length of time may be completely altered, particularly if water is present. When the alteration that begins as tarnish is complete, and all native silver has been combined with other elements, a worked piece will usually lose its integrity and disintegrate. If silver is subjected to moisture in the presence of the element chlorine, as it would in seawater or brackish water, horn silver or silver chloride may develop. 

Representative Chemicals Silver chloride (AgCl) Silver nitrate (AgNOs) Silver cyanide (AgCN)... 

Thin-film products have always been deposited on substrates of relatively small dimensions. Exceptions have been the wet chemical silvering for mirror production and perhaps the making of special oxidic heat protection layer systems by dip coating. A few other rare examples for large area coating can be given in film deposition on large astronomical telescope mirrors and on 1.2 m diameter optical components for the lasers used in nuclear fusion experiments. 

Approaching the formation of colloids from the other end of the size range involves one of several growth mechanisms. Such processes are commonly employed for the production of dispersions and aerosols, and less commonly in the production of emulsions. Typical examples of important condensation processes include fog formation (both water and chemical), silver halide emulsions (really dispersions) for use in photographic products, crystallization processes, colloidal silica, latex polymers, etc. 

Pap A, Kordas K, Peura R, Leppavuori S. Simultaneous chemical silver and palladium deposition on porous silicon FESEM, TEM, EDX and XRD investigation. Appl Surf Sci 2002 201 56-60. 

The adsorption properties of silica can be modified in a number of useful ways by impregnating the silica with an appropriate chemical. Silver nitrate is most commonly employed but boric acid, oxalic acid and sodium arsenite have also been used. This latter... 

Cheng and co-workers have coated carbon fiber by chemical silver plating [49]. 

Cheng HM, Zhou BL, Zheng ZG, Wang ZM, Shi CX, Chemical silver plating on carbon-fibers. Plating and Surface Finishing, 77(5), 130-132, 1990. 

Figure 9.3 illustrates an alternative way of looking at how biocides can be effective through their mechanisms of action . With regard to one of these biocidal chemicals, silver, an important note must be said here sometimes silver is recommended as a biocide to industrial inquirers who are not allowed to use copper or mercury, obviously for environmental concerns. It has been reported that although... 

While the stractures of silver and gold are similar, they are very different chemically. Silver chloride is veiy water insoluble (with a Ksp of 1.8xl0 °) as is gold (I) chloride, while gold (III) chloride is highly soluble (68 g/lOOg water). It is the insolubility of silver chloride in aqueous media that limits silver uses in wound care. Tables 2 and 3 show what happens to silver when 1 or 50 ppm Ag is placed in a 0.98 molar solution of sodinm chloride (equivalent to the... 

Chemical Silvering, National Bureau of Standards Circular No. 389 (1931) also reprint, Lindsay Publications, 1991. 

Chemical deposition The deposition of a metal film by precipitation where another metal ion displaces the depositing atom in a solution of the metal salt. See also Chemical silvering. 

Chemical silvering The deposition of silver from a solution by the reduction of a silver-containing chemical. Example Used in coating back-surface mirrors and vacuum flasks. 

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