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


Химия

Research of Phase Equilibriums in a System of Dibasic Organic Acids: Azelaic, Glutaric and Sebacic

Presented first the results of the research of phase equilibria of threecomponent system azelaic acid – glutaric acid – sebacic acid by used the microcalorimeter heat flow. Identified eutectic composition containing azelaic acid – 33,0 wt %, glutaric acid – 54,0 wt %, sebacic acid – 13,0 wt %. The melting temperature of the alloy eutectic composition in the three-component system is 70,5 °C, the specific enthalpy of melting is 82 ± 10 J./g.

Assessment of the Environmental Safety of Some Building Materials and Products

In recent years, much attention is paid to the environmental safety of industrial materials and products widely used in the construction of residential and public buildings. Housing quality is influenced by the choice of «clean» construction materials not containing any chemical substances harmful to human health, namely: mercury, lead, cadmium, chromium, their salts and isotopes, as well as some naturally occurring radionuclides (radium 226, thorium 232, potassium 40, and cesium 137).

Competitive Binding of K+ in the Presence of Na+ with Bovine Serum Albumin and Hemoglobin

Selective accumulation of monovalent cations K+, Na+, Rb+, Cs+ with albumin and hemoglobin is shown. Preferential sorption of potassium in the presence of sodium with test proteins is determined. It is shown that with increasing concentrations of sodium in the composition of aqueous solutions of the proteins, the amount of potassium bound by proteins increases.

Thermal Isomerization of O-Chlorophenyltetrazolocyclanopyrimidine with Different Structure Types

Temperature dependence of the 1H NMR spectra and TLC data suggest turning the corner isomers of о-сhlorоpheniltetrazolocyclanopyrimidine in the thermodynamically more stable linear forms. The IR spectra were recorded isomeric azide intermediate transformations.

Synthesis of Opto-R-Phenyl Benzimidazoloheksahydroquinazoline with Angular Articulation Rings

Condensation of 2-aminobenzimidazole, ortho-substituted benzaldehydes and cyclohexanone proceeds with the formation of 10-o-Rsubstituted phenyl benz[4,5]imidazolo-6,7,8,9,10,11-hexahydro[1,2-a] quinazolines having angular articulation rings, strukture which is set using IR, NMR, 1 H, 13C spectra.

Fluorimetric Determination of Pefloxacin in Pharmaceutical Preparation

It is shown that pefloxacin forms a terbium complexes in neutral and mildly acidic conditions which are characterized by energy transfer. It is found that the micellar surfactant medium energy transfer efficiency increases. The maximum increase sensitized fluorescence intensity is observed in the presence of SDS micelles. A fluorimetric method for determination of pefloxacin in the drug was developed.

Application of Solid-surface Luminescence for Determination Indicator Coefficients of Polycyclic Aromatic Hydrocarbons

Luminescence of PAH (anthracene, phenanthrene, pyrene, fluoranthene, benzo(a)anthracene, chrysene, benzo(a)pyrene) in aqueous media and in the solid phase of cellulose diacetate is investigated. It is established that solid surface luminescence (SSL) analysis increases the detection sensitivity of PAH in water without extraction and preconcentration with organic solvents, an exception is chrysene. The spectral characteristics show SSL-method to be using for detection of indicator isomers pairs of PAH.

Electrostatic and Hydrophobic Interactions in the System: Synthetic Food Dye Е133 – Cetylpyridinium Chloride – H2O

Investigated the conditions of formation and solubilization ion associate synthetic food dye «brilliant blue» (Е133) ions with cetylpyridinium chloride (TSPKH). The composition of the associate, the solubility in water and micelles TSPKH. The importance of such interactions in the photometric, potentiometric and other methods of determination of synthetic food dyes.

Glaukonit’s Influence on Viability and Development Seeds of Some Grain Crops

It is defined macro- and microelement composition of glaukonite ore of the Beloozersky field of the Saratov region. It is established that it contains a set macro- and the minerals necessary for a mineral delivery of plants. The possibility of application of the studied glaukonite as tools for processing of seeds of grain seeding before crops, on the example of seeds of wheat and rye is considered.

Spatial and Electronic Structure of the Pyrene Molecule, Tripaflavin Cation and Eosin Anions As a Prerequisite for Interpreting Their Solid-phase Fluorescence

At the B3LYP/6-311++G(d,p) level of theory, involving the NBO analysis, the spatial and electronic structure of the pyrene molecule, tripaflavin cation, eosin monoanion and dianion has been computed. The results obtained will offer a framework for interpreting the peculiarities of the above species solid-phase fluorescence.

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