Zinc and Cadmium

Mercury Telluride. Compounds of mercury with tellurium have gained importance as semiconductors with appHcations in infrared detection (9) and solar cells (10). The ratio of the components is varied, and other elements such as cadmium, zinc, and indium are added to modify the electronic characteristics. 

Group II Cadmium, zinc and aluminium, and their alloys... 

Aluminium is widely applied for decorative and protective requirements, while cadmium , zinc and titanium have been applied to ferrous materials chiefly for their protective value. The method finds particular application in the plating of high-tensile steels used in aviation and rocketry, car fittings and lamp reflectors, and gramophone record master discs, as well as in the preparation of specimens for electron microscopy and in rendering insulated surfaces electrically conducting, e.g. metallising of capacitors and resistors. 

In a reactor at low pressure (0.2-0.3 MPa) and moderate temperature (375 °C) the PVC is chemically and thermally degraded. A particular feature of the process is that the chlorine in the PVC reacts in part with the fillers in PVC and is neutralised with the formation of CaCl2. In similar vein, metal stabilisers in PVC are converted into the respective metal chlorides (lead, cadmium, zinc and/or barium). At current PVC waste compositions these chlorides consist of 60% lead which can be purified and re-used. The reaction in the end results in the following solid, liquid and gaseous products. 

Thus films can be divided into two groups according to their morphology. Discontinuous films are porous, have a low resistance and are formed at potentials close to the equilibrium potential of the corresponding electrode of the second kind. They often have substantial thickness (up to 1 mm). Films of this kind include halide films on copper, silver, lead and mercury, sulphate films on lead, iron and nickel oxide films on cadmium, zinc and magnesium, etc. Because of their low resistance and the reversible electrode reactions of their formation and dissolution, these films are often very important for electrode systems in storage batteries. 

Precipitation is the most promising method for immobilizing dissolvable metals such as lead, cadmium, zinc, and iron.15 Some forms of arsenic, chromium, mercury, and some fatty acids can also be treated by precipitation.47 The common precipitating chemicals for metal cations are sulfide, phosphate, hydroxide, or carbonate. Among them, sulfide is the most promising, because sulfides have low solubility over a broad pH range. Precipitation is most applicable to sites with sand or coarse silt strata. 

Xian X. 1989. Response of kidney bean to concentration and chemical form of cadmium, zinc, and lead in polluted soils. Environment Pollution 57 127-137. 

Saha U.K., Taniguchi S., Sakurai K. Adsorption behavior of cadmium, zinc and lead on hydroxyaluminum- and hydroxyaluminosilicate-montmorillonite complexes. Soil Sc Soc Am J 2001 65 694-703. 

Bruland et al. [122] have shown that seawater samples collected by a variety of clean sampling techniques yielded consistent results for copper, cadmium, zinc, and nickel, which implies that representative uncontaminated samples were obtained. A dithiocarbamate extraction method coupled with atomic absorption spectrometry and flameless graphite furnace electrothermal atomisation is described which is essentially 100% quantitative for each of the four metals studied, has lower blanks and detection Emits, and yields better precision than previously published techniques. A more precise and accurate determination of these metals in seawater at their natural ng/1 concentration levels is therefore possible. Samples analysed by this procedure and by concentration on Chelex 100 showed similar results for cadmium and zinc. Both copper and nickel appeared to be inefficiently removed from seawater by Chelex 100. Comparison of the organic extraction results with other pertinent investigations showed excellent agreement. 

CdS/ZnS Multilayer Thin Films. The low deposition temperature of SILAR allows the growth of very thin layers to achieve multilayer structures. CdS/ZnS multilayer films have been grown from separate cadmium, zinc, and sulfur precursor solutions. Multilayer structures with layer thicknesses of 2-5 nm have been fabricated, and the separate layers could be seen by SEM. RBS measurements revealed that the layers were separated with only... 

Anderson, R.L., C.T. Walbridge, and J.T. Fiandt. 1980. Survival and growth of Tanytarsus dissimilis (Chi-ronomidae) exposed to copper, cadmium, zinc and lead. Arch. Environ. Contam. Toxicol. 9 329-335. 

Brent, R.N. and E.E. Herricks. 1998. Postexposure effects of brief cadmium, zinc, and phenol exposures on freshwater organisms. Environ. Toxicol. Chem. 17 2091-2099. 

Bordin, G., J. McCourt, and A. Rodriguez. 1994. Trace metals in the marine bivalve Macoma balthica in the Westerschelde estuary, the Netherlands. Part 2 intracellular partitioning of copper, cadmium, zinc and iron — variations of the cytoplasmic metal concentrations in natural and in vitro contaminated clams. Sci. Total Environ. 151 113-124. 

Behra, R. 1993. In vitro effects of cadmium, zinc and lead on calmodulin-dependent actions in Oncorhynchus mykiss, Mytilus sp., and Chlamydomonas reinhardtii. Arch. Environ. Contam. Toxicol. 24 21-27. 

Attar, E.N. and E.J. Maly. 1982. Acute toxicity of cadmium, zinc, and cadmium-zinc mixtures to Daphnia magna. Arch. Environ. Contam. Toxicol. 11 291-296. 

Bruland, K. W., Franks, R. P., Knauer, G. A. and Martin, J. H. (1979). Sampling and analytical methods for the determination of copper, cadmium, zinc and nickel at the nanogram per liter level in sea water, Anal. Chim. Acta, 105, 233-245. 

Cadmium, Zinc, and Lead Sulfides and Their Mixed Sulfides... 

Of course, predictable differences between He(2 5) and He(23S) occur regarding the polarization of Penning ions and electrons caused by total spin conservation. The fact that a component of spin angular momentum is conserved in Pgl has been demonstrated by the observation of the transfer of spin polarization from optically pumped He(23S) atoms to the Penning ions of cadmium, zinc, and strontium.72 The polarization was detected by measuring the polarization of the light emitted from the excited 2Ds/2 ions in 2Ds/2- 2D2/2 transitions. If a component of spin angular momentum is conserved, we may write the Pgl process as... 

Pseudomonas putida growing on 3 mM cadmium synthesizes three cysteine-rich proteins of molecular weight 4000 to 7000, containing four to seven cadmium, zinc and copper atoms per molecule. The use of I13Cd NMR on the major cadmium protein shows it to be related to cadmium metallothionein, but with some significant differences.I223b... 

H. L. Wells, and H. Klinger s basic nitrates of lead, cadmium, zinc, and mercury were shown by G. Watson to fall in line with this hypothesis but F. Meissner could not support it, and F. W. Kuster and R. Kremann showed that the f.p. curve of binary mixtures of nitric acid and water invalidates H. Erdmann s conclusions— vide infra. 

Harvey RW, Luoma SN. 1985. Effect of adherent bacteria and bacterial extracellular polymers upon assimilation by Macoma balthica of sediment-bound cadmium, zinc and silver. Mar Ecol Prog Ser 22 281-289. 

Generally speaking, atoms in doublet and triplet states are reactive and tend to form chemical bonds either with themselves or with other atoms or molecules. Hence the photochemist is concerned in practice with gas phase photochemical reactions of mercury, cadmium, zinc, and the noble gases whose atoms exist normally in singlet states. 

N-(2,3-Dimercaptopropyl)phthalamidic acid (41, DMPA) has been shown to form relatively stable complexes with cadmium, zinc and mercury312. DMPA has also been shown to enhance faecal and urinary excretion of mercury in mice and arsenic in mice and rabbits. For the decorporation of arsenic, taken in as arsine, the administration of 3-(tolylthio)propane-l, 2-dithiol (42) has been proposed in the USSR313. ... 

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