Silver compounds transport

Many silver compounds are unstable to light, and are thus shipped ia brown glass or opaque plastic bottles. Silver compounds that are oxidants, eg, silver nitrate and iodate, must be so identified according to U.S. Department of Transportation (DOT) regulations. Compounds such as silver cyanide, which is toxic owiag to its cyanide content, must carry a poison label. However, most silver compounds are essentially nontoxic. 

Environmental Fate. The factors governing the environmental fate of silver are not well characterized. While silver and its compounds are transported in the air, water, and soil, and are partitioned between these media, the mechanisms of transport and partitioning are not well-defined. No partition coefficients or constants have been determined for silver or its compounds. Little information was found in the available literature on transformation of silver in water or soil. Some microorganisms present in these media may be able to transform silver and silver compounds however, silver is not expected to be significantly transformed in the environment because it is toxic to microorganisms. Further information on the size and flux of environmental compartments and the transport and transformations of silver and silver compounds in the environment would be useful in defining pathways for potential human exposure. 

Solid electrolyte coulometers developed so far use silver conducting compounds Ag SBr (32) Ag3 SI (33) and Rb Agj 15 (3 ) between a silver and a metallic electrode. In operation a known amount of silver is transported and plated on the other electrode. After storage, this amount is stripped away by a current in the reverse direction and transported back to the silver electrode. 

Ritz, M. C., R. J. Lamb, S. R. Goldberg, and M. J. Kuhar. 1987. Cocaine receptors on dopamine transporters are related to self-administration of cocaine. Science 237 1219-1223. Rodgers, J. H., Jr, E. Deaver, B. C. Suedel, and P. L. Rogers. 1997. Comparative aqueous toxicity of silver compounds laboratory studies with freshwater species. Bull. Environ. Contamination Toxicol 58 851—858. 

No long-term research studies on the environmental fate of silver were identified. However, environmental monitoring being conducted in conjunction with remedial investigation/feasibility studies at NPL sites where silver has been found should add useful information regarding environmental concentrations, chemical species, fate, and transport of the compounds. 

The temperature dependence of I/U characteristics for the p-Si/PI/Cao nanosystem with etched SHI tracks is rather complicated in the present research. The most clear current rise is observed only at 60 C. This current increase can indicate narrowing of the energy band gap due to diffusion of silver from the contacts into the fullerite and formation of C6o-Ag compounds, which should facilitate the current transport. 

Synthesis of Phosphoric Acids and Their Derivatives. - A series of monoalkyl and dialkyl phosphorus acid chiral esters have been synthesised for use as carriers for the transport of aromatic amino acids through supported liquid membranes. The compounds acted as effective carriers but enantio-separation was at best moderate. A range of phosphono- and phosphoro-fluoridates have been prepared by treatment of the corresponding thio- or seleno- phosphorus acids with aqueous silver fluoride at room temperature (Scheme 1). In some cases oxidation rather than fluorination occurred. Stereospecifically deuterium-labelled allylic isoprenoid diphosphates, e.g. (1), have been synthesised from the corresponding deuterium-labelled aldehyde by asymmetric reduction, phosphorylation and Sn2 displacement with pyrophosphate (Scheme 2). ... 

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