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The aim of the study was to study the content of some heavy metals and arsenic in frozen fish (capelin, herring, pink salmon, chum salmon, pollock, blue whiting, greenling) used for feeding animals of zoological institutions. In the course of the study, it was found that according to the value of the average content in fish used by zoological institutions for feeding wild and exotic animals, the studied elements form the following decreasing series: Fe > Zn > Cu > As > Pb > Cd. In the course of nonparametric statistics, significant differences were established in the level of accumulation of all studied elements, except for Pb and Cd, by representatives of different fish families. Herring is characterized by a high level of accumulation of Zn and As, low – Cd, salmon: high concentration of Fe, Pb, Cd, low – Cu and As. Greenlings to a greater extent than other families contain Cu, to a lesser extent – Zn and Fe. The rest of the elements in the representatives were kept at an average level. In the studied fish samples, the excess of MPC was not found. The presence of a reliably weak direct correlation the relationship between the content of Pb, Cd and As in fish and animal biosubstrates was established, and the antagonism between the intake and accumulation of the following elements in the body of birds and mammals was statistically confirmed: Zn – Pb, Cu – Pb and Zn – Cd. The accumulation of As in biosubstrates is facilitated by the intake of Zn and Cd, and Cu – Zn.

The chromatographic behavior and adsorption of enantiomers of glycylaspartic acid on the Nautilus-E chiral stationary phase with grafted eremomycin antibiotic were studied. Acetate buf er mixtures with variable pH prepared in a water—methanol mixed solvent (volume ratio 60 : 40) were used as acetate buf ers. The retention of Gly—Asp was found to be enantioselective and depending on the ratio of various ionic forms of dipeptide in the mobile phase. The ratio is determined by the pH. A model of adsorption equilibrium assuming independent binding of diverse ionic forms with the stationary phase, which is characteristic of energy uniformity, was proposed. This model is well consistent with the experimental data. Features of application of the equilibrium dispersion and transport dispersion dynamic elution models for the determination of the adsorption isotherms by the inverse method are discussed.

Most of the kaolin deposits are confined to weathered paleolithic rock. Intensively metamorphosed rocks lie above the weathered depth while below they gradually change into permanent parent rocks. The deposits of kaolin which arise from leucocratic, porphyric, and other granites are of the greatest industrial interest. When they are formed, the ironmineral ores (pyrites, magnetite, etc.), of course, dissolve and are removed. In the first stage of weathering these ferrous silicates produce ferrous montmorillonite minerals which change into kaolinite. During this process some of the iron and titanium is removed while some remains inside the flakes of kaolinite and lowers the whiteness [i].