Cadmium atomic properties

Metallothioneins (MT) are unique 7-kDa proteins containing 20 cysteine molecules bounded to seven zinc atoms, which form two clusters with bridging or terminal cysteine thiolates. A main function of MT is to serve as a source for the distribution of zinc in cells, and this function is connected with the MT redox activity, which is responsible for the regulation of binding and release of zinc. It has been shown that the release of zinc is stimulated by MT oxidation in the reaction with glutathione disulfide or other biological disulfides [334]. MT redox properties led to a suggestion that MT may possesses antioxidant activity. The mechanism of MT antioxidant activity is of a special interest in connection with the possible antioxidant effects of zinc. (Zinc can be substituted in MT by some other metals such as copper or cadmium, but Ca MT and Cu MT exhibit manly prooxidant activity.)... 

Therefore, the suggested equation (2.19) reflects adequately a variation in the properties of luminescence quenchers and describes well the experimental data as a whole. In addition, the data suggest that for the colloids obtained with an excess of the sulfide ions, the quencher adsorption site is represented most likely by the negatively charged surface sulfur atoms, on which the cations adsorb readily while the anions adsorb poorly. Actually, in this case, the dominant surface defects are either the vacancies of the cadmium ions, or... 

In the presence of AIH3 we have considered synthesis reaction of cadmium iodide at bombardment of mixture CdS + J [23] with hydrogen atoms. We have investigated catalytic properties of A1H3 at opening of different minerals [24]. 

That this ratio of atoms to electrons is indeed determinative of the properties in many metallic systems is also seen from the solubility in the melt and likewise in the solid state. Zinc dissolves in the solid state in copper up to 38.4 % as a homogeneous mixed crystal (a-brass, the normal brass contains about 35 % zinc) almost the same limit of about 40 % holds for the combinations of the elements copper, silver and gold with zinc and cadmium. 

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