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The processing was investigated of activated carbon saturated with 3 160 g/t Au and 4 490 g/t Ag as Au(I) and Ag(I) cyanide compounds and containing non-ferrous metals at 47 g/t Pb, 736 g/t Zn and 760 g/t Cu, as well as 0.73% Fe and 4.5% Ca in insoluble Ca compounds. Possible processing options were the Zadra method; the addition of NaCN solution with ethanol, methanol, acetonitrile or similar; the AARL method; and the IPS method. Acid washing of the activated carbon before desorption of the precious metals using NaOH at 150 degrees C resulted in a reduction in the Ca impurities on the adsorbent surface but had a negative effect on the desorption of Au(I) and in particular Ag(I). Addition of NaCN to the eluant solution slightly improved precious metal extraction from the activated carbon but was accompanied by breakdown of the NaCN under the severe Au(I) desorption conditions and by losses of Ag(I). Acid washing of the activated carbon after the elution of Au(I) was preferred but did not resolve the problem relating to the desorption of Ag(I) compounds. The use of acid washing before or after desorption had little effect on the removal of Fe, Ni and Zn compounds, and cyanide complexes of these metals were characterised by a low adsorption affinity for activated carbon. Possible causes of the elution issues are discussed and methods for reducing the negative effect of the impurities are suggested., The processing was investigated of activated carbon saturated with 3 160 g/t Au and 4 490 g/t Ag as Au(I) and Ag(I) cyanide compounds and containing non-ferrous metals at 47 g/t Pb, 736 g/t Zn and 760 g/t Cu, as well as 0.73% Fe and 4.5% Ca in insoluble Ca compounds. Possible processing options were the Zadra method; the addition of NaCN solution with ethanol, methanol, acetonitrile or similar; the AARL method; and the IPS method. Acid washing of the activated carbon before desorption of the precious metals using NaOH at 150 degrees C resulted in a reduction in the Ca impurities on the adsorbent surface but had a negative effect on the desorption of Au(I) and in particular Ag(I). Addition of NaCN to the eluant solution slightly improved precious metal extraction from the activated carbon but was accompanied by breakdown of the NaCN under the severe Au(I) desorption conditions and by losses of Ag(I). Acid washing of the activated carbon after the elution of Au(I) was preferred but did not resolve the problem relating to the desorption of Ag(I) compounds. The use of acid washing before or after desorption had little effect on the removal of Fe, Ni and Zn compounds, and cyanide complexes of these metals were characterised by a low adsorption affinity for activated carbon. Possible causes of the elution issues are discussed and methods for reducing the negative effect of the impurities are suggested.

The purpose of this article is determining the sociocultural features of adjustment of Chinese students to study in Russian universities. The expansion of bilateral economic relationship between Russia and China has led to a growing interest of Chinese young people towards receiving higher education in Russian universities. Simplified procedure of admission of foreign students leads to complication of their cultural adjustment to a new sociocultural environment. The article presents the results of sociological survey of Chinese students studying in the technical university. It is concluded that the transition of a foreign student to a new society is accompanied by culture shock. Symptoms of culture shock and phases of cultural adjustment process are highlighted in the present article on the bases of K.Oberg methodology. According to U-curve cultural adjustment model proposed by Lysgaard S., the adapting person overcomes three main phases: initial adjustment, crisis state, and final adjustment. The analysis of the conducted survey has confirmed that adjustment to a new culture takes place according to the U-curve by Lysgaard. Determination of ways to solve the problem of foreign students' adjustment to study in Russian universities is associated by the author with the identification of sociocultural characteristics of a specific country. It is revealed that the peculiarities of adjustment of Chinese students to study in Russian universities include sociocultural, psychological, and didactic features. In this connection, it is necessary to determine the extent of the impact of these characteristics on the adjustment process of Chinese students. © 2017.