Cadmium deposition cell studies

It should be pointed out that this deposition was carried out for films ca. 50 nm thick the study was carried out with CdS window layers for solar cells in mind, which are usually thin. It is possible that much longer depositions result in different impurities. Thus the sparingly soluble cadmium carbonate and cyanamide will be converted to CdS if enough sulphide ion is formed with time (or, for the complex-decomposition mechanism, if enough adsorbed thiourea decomposes on the surface of the solid phases). Of course, longer time also means more thiourea decomposition products. 

Mercury represents a serious environmental risk, and the study of removal of mercury from wastewater has received considerable attention in recent years. Mercury concentration was usually reduced by deposition on a cathode with high surface area. Removal of mercury is studied using extended surface electrolysis which reduces the level of mercury to below acceptable concentrations of 0.01 ppm in wastes by employing a Swiss roll cell with a cadmium-coated, stainless-steel cathode. An industrial cell with a fluidized bed electrode has also been studied. Graphite, as an efficient porous electrode, has been used to remove traces of mercuric ions form aqueous electrolyte solutions. In order to apply the electrochemical method for some effluents, it is necessary to use sodium hypochlorite to convert elemental mercury and less soluble mercury compounds to water-soluble mercuric-chloride complex ions. 

Although the major part of the brain seems to be quite efficiently protected against the penetration of cadmium by the blood-brain barrier, there are certain regions of the CNS that are devoid of this barrier and autoradiographic studies indicate that cadmium may accumulate in such areas. Experimental studies are needed to determine whether the deposition of cadmium in these regions leads to neural cell damage. 

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