Photographic emulsions products

Thiazole disulfides are reported to yield quantitatively A-4-thiazoline-2-thiones under treatment with zinc powder in acetic acid (326). The disulfide bond can be broken on heating at 100 to 260°C and (or) by alkali. This property has been used for photographic emulsions (327). The disulfide (136) (R = 4-(D-arabmo-tetrahydroxybutyD can be cleaved readily by aqueous sodium hydroxyde. carbonate, or hydrogen carbonate (149) to give 135 a by-product, 4-(D-arabino-ietrahydroxybutyl) thiazole... 

Uses. Vulcanization accelerator for type of rubber usually used in the production of household rubber gloves rather than medical rubber gloves corrosion inhibitor in metal-working fluids, detergents, antifreeze, and photographic emulsions. 

The conditions required to form an emulsion of oil and water and a microemulsion. The complex range of structures formed by a microemulsion fluid. Emulsion polymerization and the production of latex paints. Photographic emulsions. Emulsions in food science. Laboratory project on determining the phase behaviour of a microemulsion fluid. 

Standard autoradiography film can be used to visualize ECL reactions, although Amersham does provide a number of products that have been optimized for use in this procedure. Hyperfilm -ECL and Hyperpaper -ECL are both recommended Please note that Hyperpaper-ECL has photographic emulsion on only one side, so the appropriate side must be exposed to the membrane (the emulsion side has a glossy appearance). 

Many uses of dextran in petroleum production have been proposed. It has been tested successfully for use in drilling muds,354,355 and in viscous water-flooding.356,357 The patent literature332 suggests that the native, high-molecular-weight dextran is now used in various proprietary, X-ray and photographic emulsions. 

Rhodium compounds and complexes are also commercially important catalysts. The hydroformylation of propene to butanal (a precursor of hfr(2-ethyUiexyl) phthalate, the PVC plasticizer) is catalyzed by hydridocarbonylrhodium(I) complexes. Iodo(carbonyl)rhodium(I) species catalyze the production of acetic acid from methanol. In the flne chemical industry, rhodium complexes with chiral ligands catalyze the production of L-DOPA, used in the treatment of Parkinson s disease. Rhodium(II) carboxylates are increasingly important as catalysts in the synthesis of cyclopropyl compounds from diazo compounds. Many of the products are used as synthetic, pyrethroid insecticides. Hexacyanorhodate(III) salts are used to dope silver halides in photographic emulsions to reduce grain size and improve gradation. 

Gelatin is also widely used in food products and photographic emulsions. 

Two aspects of AgBr behavior must be emphasized (Figure 1). the production of practical photographic "emulsions" or film coat-... 

Proteins are biopolymers that are encountered in many applications, such as food emulsions, hair conditioners, photographic emulsions, and various medical diagnostic products. Many of these applications are frequently based on the unique surface activity of the proteins, which is reflected in functional properties such as foaming, emulsification, and gelling. The proteins are composed of polymeric chains containing many hydrophobic and hydrophilic domains, often giving the molecules an amphipathic structure somewhat similar to that of polymeric surfactants. 

This explains why freshly abraded Zn when corroded by the atmosphere in close proximity to a photographic plate activates the photographic emulsion (Russell effect) (6). Cd, Mg, and A1 behave similarly. However, for metals which catalyze the decomposition of H2O2, like Fe, Cu, brass, Pb, and Sn, no corresponding darkening of the plate results. The marked abihty of iron to catalyze the decomposition of hydrogen peroxide accounts for the fact that this substance is not a component of ferrous corrosion products. 

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