Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


Химия

ФАЗОВАЯ ДИАГРАММА ДВОЙНОЙ СИСТЕМЫ ФОРМИАТ КАЛИЯ - ВОДА

A technique of laboratory  synthesis  of potassium formate has  been developed. Phase equlibria in mixtures  of the components  of the binary  system potassium formate - water in the range from -70 to +170°C were investigated by  the visual-polythermal method. For the first time the phase diagram of the specified system has  been con­ structed and the coordinates  of an eutectic  point has  been estab­ lished. The formation of a crystalline hydrate КНСООИ.бНгО incon­ gruous  melting at -9.2°C was  found in this  system.

ТЕРМОДИНАМИКА ПРОЦЕССА КОМПЛЕКСООБРАЗОВАНИЯ В СИСТЕМЕ РЗЭ - О-ФТАЛЕВАЯ КИСЛОТА

Потенциометрическим методом исследовано комплексообразо­вание редкоземельных  элементов (РЗЭ) La, Се, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm и Yb с о-фталевой кислотой при р = 0.2(KCI) в интервале температур 298-328 К. В области pH = 3.8-5 обна­ружено существование комплексной частицы состава LnL , где

Quantum Chemical Study and QSAR Properties of 3-Seleno- pentanediones-1,5 Aromatic Derivatives: Prerequisites for Inter­ action with the Carbohydrate-Binding Proteins

The role of spatial and electronic  structure, hydrophobic  properties and concentration of organoselenium compounds  on their interaction with fungal metabolites  - carbohydrate-binding proteins, extracellular lectins  of Lentinula edodes (shiitake mushroom) has  been consi­ dered. By  the hybrid density  functional theory  method at the B3LYP/6-31G(d,p) theory  level, spatial and electronic  structure of the 1,5-di(4-R-phenyl)-3-selenopentanediones-1,5 molecules  has  been studied.

Influence of the Cantomination of Several Strains of Helicobacter pylori on Ulcer Disease Development, Stomach Cancer, and Their Complications

The bioptates  of 170 patients  with ulcer disease and stomach cancer were analyzed to reveal Helicobacter pylori with the help of histological and molecular-genetic  techniques. The cantomination levels  of Helicobacter pylori in various  clinical cases  were determined. The most virulent strains responsible for complication development, including ulcer-cancer transformations, were revealed.

ЭКСПЕРИМЕНТАЛЬНОЕ ОПРЕДЕЛЕНИЕ ЭНЕРГИИ АКТИВАЦИИ И ДРУГИХ ТЕРМОДИНАМИЧЕСКИХ ВЕЛИЧИН В ПРОЦЕССЕ ИЗУЧЕНИЯ КУРСА ОБЩЕЙ ХИМИИ

В процессе изучения химических и других естественно-научных дисциплин в аграрных ВУЗах возникает острая проблема нехватки аудиторных часов. Мы считаем, что в данных условиях необходимо интегрировать линии содержания дисциплин как внутри предметов, так и с другими дисциплинами. Внутри- и межпредметная интеграция обеспечивает усвоение содержания преподаваемых дисциплин, а также приобретение учащимися необходимых компетенций.

Transformations of substituted cyanoiminooctahydroquinazolines under oxidation conditions

Substituted quinazolines of various degrees of saturation and functionalization possess a wide spectrum of biological activity, in particular, anticancer activity, which predetermines the importance of obtaining new representatives of this type of compounds and studying their practically useful properties. Methods for the preparation of 2-cyanoiminoquinazolines are poorly described in the literature, while their properties and oxidation reactions have not been studied at all.

Microextraction preconcentration with nonionic surfactants and colorometric determination of phenol

The extraction of the tungsten blue complex formed by the reaction of phenol with Folin-Ciocalteu reagent (FCR) in the presence of a nonionic surfactant Triton X-100 in alkaline medium using the methodology of micellar extraction based on «clouding point» has been studied for the fi rst time. Aqueous solutions of sodium carbonate and sodium sulfate were used to create pH and as a desalting agent.

Investigation of the properties of the solid residue of the pyrolysis of sewage sludge

This article presents the results of the thermal processing of sludge from domestic wastewater under laboratory conditions. The pyrolysis process is carried out in a batch reactor with an original design. Gaseous and liquid forms of hydrocarbon compounds, as well as solid carbonaceous residue, were obtained after processing the sludge in a pyrolytic plant. It is established that during pyrolysis of sludge sewage sludge, the output of the process products depends on the heating rate of the raw material.

Study of the activity of bifunctional catalyzers on the transformation of n-hexane

The production of various motor fuels is carried out by processing light fractions of oil with an initial temperature of boiling to 350°С. The current trend shows that oil in new fi elds has more weight than before. New oil reservoirs are deeper with a greater proportion of dark fraction with a boiling point of 350°С. This situation stimulates to fi nd new ways of increasing the processing depth light fractions for synthesis target product. One of the main solution path for the problem is creation of new catalytic systems or modernization of existing ones.

Analytical reactions of 2,4-dinitrophenylhydrazine with some aldehydes in micelles of cationic surfactants

The analytical eff ect of micelles of cationic surfactants in the reactions of some aromatic aldehydes (AA) with 2,4-dinitrophenylhydrazine (DNPH) with the formation of the corresponding aci-forms of hydrazones has been established. It has been established that micelles of nonionic and anionic surfactants do not cause analytically signifi cant eff ects in the system under study.

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