Химия

In this paper the high efficiency of the anionic absorbent polymer in the sorption and desorption of samples of aqueous solutions of organic substances. Recommended that the optimal conditions for use as a sorbent sample of water objects of the environment in the process of chemical and analytical monitoring of environmental pollutants of natural and anthropogenic origin.

The stable tetrahedron LiF-KF-KCl-K2WO4 of the quinary reciprocal system Li,K||F,Cl,WO4 was studied by differential thermal analysis, and the characteristics of eutectic and peritectic were determined.

First held reduction reaction of benzannelated hexahydroselenochromenes. Reduction was carried out by ionic hydrogenation, which has led to under-previously unknown benzannelated hexahydroselenochromenes. It has been found that the reduced products are obtained generally in the form of a mixture of two isomers in a ratio of 1: 1.

Изучены особенности влияния природы второго лиганда, мицелл ПАВ на интенсивность сенсибилизированной флуоресценции хелатов европия (III) с некоторыми производными тетрациклина. Предложен подход к флуориметрическому определению суммы трех тетрациклинов и повышению избирательности, заключающийся в измерении интенсивности эмиссии хелатов с помощью стационарной и разрешенной во времени флуоресценции. Установлено оптимальное время задержки измерения

The phase diagram of the potassium thiocyanate–water binary system was studied by the visual polythermal method and by the method of time–temperature curves over а temperature range – 35–180 оС. There is an eutectic equilibrium at –32.6 оС in the system; the solid phases of this equilibrium are ice and individual potassium thiocyanate. The composition of the liquid phase of the eutectic state was determined.

The article presents the results of the development of technical decisions of processing of products detoxification lewisite in the arsenic oxide (III). Shows a general scheme and the basic process steps of this process. Particular attention is paid to the method of removal of arsenic (V) from the system, which can contaminate the final product. 

Natural bentonite was modified with iron (III) and aluminum polyhy- droxocations by the sol–gel technique. This modification of natural bentonite has been found to cause changes in its chemical composi- tion, structural and sorption properties. The modified sorbents are fine-porous (nanostructured) objects with the predominance of 1.5–6.0 nm pore size. The specific surface area of our sorbents depends on the method of modification and the amount of the modifying component introduced (iron (III) or aluminum).

The products of the derivatization of methylphosphonic acid and its ethers were investigated by gas chromatography – mass spectrometry. The optimum conditions of the derivatization of higher-boiling organo- phosphorus compounds were described.

The effect of temperature, isotopic composition of water and ethanol on the tautomeric equilib- rium of two phenylazonaphtholes that differ by sulphonic group in benzene ring was investigated spectrophotometrically. It was established that enhancement of water structure under decrease of temperature or change of common water to heavy one shifts the azoquinonhydrazone tautomeric equilibrium to more polar hydrazone tautomer.

The molecular ions fragmentation canals of substances registered by means of the GC-MS method in the media of Lentinula edodes (shiitake) basidiomycete submerged cultivation in the presence of diacetophenonylselenide have been substantiated. At the B3LYP/6-311++G(3df,3pd) and UB3LYP/6-311++G(3df,3pd) level, involving the NBO analysis and the R. F. W. Bader’s «Atoms in Molecules» quantum theory (QTAIM), isomeric transformations of dihydrofurans have been considered.