Vol. 46 No. 2 (228) (2012)

The spectroscopic properties of lignin solution in DMSO by UV and fluorescent methods have been studied. It has been shown that during dilution of this solution with small quantity of DMSO the intensity of UV absorption increases, while in the fluorescent spectra a new emission peak appears.

Using classical physicochemical (calorimetry, electroconductivity, pH-metry) and spectroscopic (IR, UV/vis) methods the effect of dimethylsulfoxide (DMSO) on urea bovine serum albumin (BSA) interactions have been studied. First of all the structural peculiarities of urea aqueous solutions in the presence of DMSO and then in these solutions the thermal and chemical denaturation of BSA has been determined. It has been established that in DMSO containing solutions (up to 10%, v/v) urea solvate shell structure changes by inclusion of DMSO molecules. At mentioned conditions BSA thermal and chemical denaturation proceeds according to reversible multistep mechanism. After denaturation some structural unities of BSA ternary structure remain.

The hydrolysis of 3-cyano- and 3-carbethoxy-4,5-diphenyl-Δ³-butenolidеs in the presence of hydrochloric or sulfuric acids as well as in sodium hydroxide has been realized. It has been shown that 3-cyano-4,5-diphenyl-Δ³-butenolidе in the presence of hydrochloric acid either at 40⁰C, or when boiled converts into 3-amido-Δ³-butenolidе, but in the presence of 30% sulfuric acid with quantitative yield by 3-carboxy-Δ³-butenolide is obtained. The latter when heated to 170⁰C undergoes decarboxylation with the formation of 4,5-diphenyl-Δ³-butenolidеs. 3-Carboxy-4,5-diphenyl-Δ³-butenolide is obtained also by hydrolysis of 3-carbethoxy-4,5-diphenyl-Δ³-butenolidе in the presence of sulfuric acid as well as 10% sodium hydroxide.

Influence of halide ions (chloride-, bromide-) on the solvent extraction of ion associates of cadmium with malachite green and fuxine has been studied. The optimal conditions of formation and extraction of ion associates have been examined, medium acidity, nature and concentration of halide ions, basic dyes. Comparative characteristic of halogenide complexes of cadmium is given, according to its solvent extraction complexes: iodide > bromide > chloride. The developed method with bromide complexes was used for determination of cadmium contents in tobacco.The method in more selective, but small sensetive, than method with iodide complexes.

In this work the nitridation process of niobium within the temperature range 1200–2100⁰C and the pressure of gaseous nitrogen 20–300 Torr was investigated. Dynamics of the niobium nitridation was explored both under isothermal and nonisothermal conditions. The influence of nitrogen pressure on the phase composition of products and phase formation mechanism was revealed.

Influence of components of potassium persulfate (PP)–dimethylamino-ethanol (DMAE) initiating system on sodium pentadecylsulfonate (PDSN) micelle formation has been studied using various physico-chemical methods. It has been shown that under the influence of compounds the critical concentration of micelle formation decreases. Intermolecular interactions in PDSN–H₂O–DMAE (PP) system has been discussed on the base of density changes.

The influence of glycine, serine and leucine on adsorption parameters of sodium pentadecylsulfonate on the surface of bentonite was studied. It was shown that adsorption of sodium pentadecylsulfonate is more effective in the presence of leucine. The hydrophobic interactions play a significant role in the process of adsorption. The obtained experimental data were analyzed by the adsorption models of Lengmuir and Freundlich.

The purification procedure of D-amino acid oxidase from Candida guilliermondii was improved. An initial induction of the enzyme was performed by adding DL-alanine to cultivation medium composition. By means of twice chromatofocusing and without the step of hydrophobic chromatography it was available to obtain purified preparation of D-amino acid oxidase with higher yield.

Blood serum of people with Mediterranean Fever was investigated by the methods of spontaneous and enhanced chemiluminescent analysis (photo- and electroinduced chemiluminescence (ChL)). Data have shown that the intensity of spontaneous ChL in the probes goes up by increasing the temperature, while the kinetics of free radical processes in course of photo and electro enhanced ChL, on the contrary, decreases exponentially. The intensity of blood serum ChL of people with Mediterranean Fever is remarkably higher comparing with the blood serum ChL level of control group and it is increasing even more during the crisis.

In various organs of rabbits exposed to vibration, electromagnetic radiation and their combined effect the activity of ornitintransaminaz and proline-5-carboxylate reductase involved in the biosynthesis of proline was explored. It is established that the highest activity of enzymes involved in biosynthesis of proline is in the liver. As well as the activity of enzymes was absent in the brain. With prolonged exposure of vibration and electromagnetic radiation on all investigated organs, increased activity of enzymes involved in the biosynthesis of proline was observed. It is assumed that during the influence of physical factors the increasе in the amount of proline has an adaptive character.

It has been revealed that bacterial insecticides of BT species, isolated by us from dead caterpillars of fruit moth and winter geometrid, after introduction into typical chernozem planted with cabbage are being preserved in the given environment during 4–5 months and maintain intrinsic for mother strain ability to synthesize spores and crystals, as well as to show high biological effectiveness against caterpillars of diamond-back moth.

The conditions for precipitation of iron arsenate from acidic solutions containing Pb, Fe, Cu, Zn and As are investigated. The following is defined: the relative concentrations of iron and arsenic, the effect of acidity, as well as the degree of deposition of arsenic and iron on the duration of the process. It is shown that the value of pH 4, in the ratio of Fe:As=5:1 and in the process duration 1.5 hours, the solution precipitates out about 90% As and 24% Fe. Residual arsenic in solution after precipitation is less than 0.1 g/L. The obtained results can be used in the purification of hydrometallurgical solutions.