Chemistry

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.

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.

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.

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.

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).

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.

Topological Transformation of Phase Diagrams for Сut 1 of the Quaternary System Potassium Nitrate – Water – Pyridine – Butyric Аcid in 5–60оС

Phase equilibria and critical phenomena in component mixtures of the cut 1 of the quaternary system Potassium Nitrate – Water – Pyridine – Butyric Аcid whose constituent ternary liquid system had a closed binodal curve were studied by means of the visualpolythermal method within 5–60oC. The volumes of two monotectic states in the composition tetrahedron have been found to be in contact via critical tie lines with increasing temperature.

Adsorption of Fe2+, Mn2+, Cu2+, Cd2+ Cations Using Granular Glauconite Sorbents

The adsorption properties of granular glauconite sorbents and their modified analogues against with respect to Fe2+, Mn2+, Cu2+, Cd2+ cations were studied and compared with natural untreated samples. The process was carried out in a static mode. The maximum adsorption of samples and the calculated adsorption equilibrium constants were determined. It was established that modified sorbents possessed the most activity adsorption against cations in pelleted samples. Modification was carried during sequential heat and acid-salt treatment.

Luminescent Properties of Samarium (III) in the Presence of Same Tetracycline Derivatives

Manifestation system to effect luminescence complexes of samarium (III) and gadolinium (III) in the presence of thenoyltrifluoroacetone and 1,10-phenanthroline. Increased intensity supersensitivity transition in luminescent ion complexing agent depends on the nature of the ligand and the formation of micro- and nanoparticles in the system. It is found that in the presence of tetracycline derivatives sensitized fluorescence intensity decreases.

Simultaneous Determination of Synthetic Food Dyes E102 and E110

The method of derivative spectrophotometry with measurements at zero-crossing wavelenghts is proposed for simultaneous quantitative determination of synthetic food dyes Tartrazine (E102) and «Sunset yellow» (E110). The method was tested on model mixtures and applied to determine the content of dyes in carbonated soft drinks. The error does not exceed 7%.

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