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Quantum Chemical and Infrared Spectrometric Studies Sulfoderivatives Di- and Triphenylamines

Authors: Burmistrova N. A., Mushtakova S. P.

The result of quantum-chemical studying of geometric characteristics for aromatic amine sulfoderivatives at MP2/6-31G(d,p) as well as experimental and theoretical investigation of IR spectra of these compounds are presented. It was shown for triphenylamine (TPhA) and triphenylamine-4-sulfonic acid (TPhASA) that theoretical vibrational spectrum was in good agreement with experimental data.

Multivariate Regression Methods for Simultaneous Сatalimetry Determination of Iridium (IV) and Rhodium (III)

Authors: Burmistrova N. A., Chernozubova E. V., Mushtakova S. P.

Application of multivariate regression methods for catalimetry simultaneous determination of iridium (IV) and rhodium (III) based on oxidation of N-methyldiphenylamine-4-sulphonic acid by periodations in weak acid medium was investigated. The data structure of the kinetic measurement was studied with Principal Component Analysis, it was found that the distribution of the samples corresponds to an increase in the total concentration of the catalysts of the PC1 and change the concentration ratio Ir: Rh on PC2.

Quantum-chemical Evaluation of Thermal Stability of Some Lanthanide Complexes with Methoxybenzoate

Authors: Pozharov M. V., Zakharova T. V., Makushova G. N., Kosolapova M. Y.

Structural and energetic parameters of neodymium, europium, terbium and erbium complexes with 2- and 3-methoxybenzoic and 3,4-dimethoxybenzoic acids were studied. Correlation between Ln-O bond energy and temperatures of decomposition of studied compounds was found.

Phase Equilibria and Critical Phenomena in the Water–i-Butyric Acid Binary System

Authors: Smotrov M. P.

Phase equilibria and critical phenomena in the water-i-butyric acid binary system were studied by the visual polythermal method over the temperature range –10–30°C. The system is characterized by delamination with an upper critical solution temperature (UCST) equal 25.8°C. In the system at –1.8°C, these occurs a nonvariant monotectic equilibrium whose solid phase are ice crystals. The phase diagram of the system is plotted.

Determination of the Main Substances in the Preparations of Cephalexin and Cefuroxime Axetil

Authors: Kulapina E. G., Karenko V. A., Kulapina O. I.

Techniques of determination of the main substances in capsules of cephalexin and tablets of cefuroxime axetil have been elaborated. For separation of ancillary compounds, the two modes have been approbated, i.e. filtration and centrifugation. The advantage of the second means has been shown.

Determination of Caffeine and Some Food Additives Wines, Energy and Soft Drinks

Authors: Selifonova E. I., Salkova D. V., Chernova R. K.

The method of capillary electrophoresis to determine the content of caffeine and food additives: ascorbic (E300), sorbic (E200), benzoic (E210) acids; sweeteners – saccharin sodium (E954), acesulfame potassium (E 950) in wines, energy drinks and tea. The comparative characteristic of the caffeine content, and the aforementioned food additives in beverages. A comparison with the corresponding regulations. It is shown that the concentration of benzoic acid in beverages above the maximum allowable concentration in beverages Flesh and MONETO.

Stereochemical Aspects of Reaction of 1,3-dipolar Cycloaddition in a Row of Conjugated Enones

Authors: Aniskov A. A., Klochkova I. N., Schekina M. P., Andreev K. A., Tumskiy R. S.

The reaction of 1,3-dipolar cycloaddition of conjugated aryl(hetaryl) methylideneacetones, which containing various peripheral substituents, with azomethine ylides was carried out. It was established that the interaction is not chemoselective and proceeds with the participation of two non-equivalent reaction centers of dipolarophile with high diastereoselectivity. The products of cycloaddition were a mixture of structural isomers endo-cycloaddition. Monoenone transform to spyropyrrolidines with high endo-stereoselectivity.

Synthesis of Spiro-fused Hydropyrimidinthiones with Use of Thiobarbituric Acid

Authors: Klochkova I. N., Aniskov A. A., Schekina M. P., Tumskiy R. S.

The conditions for the preparative synthesis of spiro-fused hydropyrimidinthiones based on carbonyl substrates and thiobarbituric acid were found. Schemes of condensation carbo- and heterocyclization are presented. Regio- and stereoselectiveness processes was established.

Sorption-fluorimetric Determination of Enrofloxacin with Magnetite Nanoparticles Modified by Polyethylenimine

Authors: Egunova O. R., Reshetnikova I. S., German S. V., Kazimirova K. O., Khabibullin V. R., Zhelobitskaya E. A., Shtykov S. N.

A technology for magnetite nanoparticles surface modification by polyethylenimine was proposed. The sizes of the nanoparticles using transmittance microscopy method were determined. The influence of pH, time of mixing, sorbent and antibiotic concentration on the enrofloxacin sorption was investigated and optimal conditions of extraction were found. Enrofloxacin sorption from plasma-modelling solution was studied and was shown that that in optimal conditions the extent of sorption is 78% and desorption from magnetite modified nanoparticles using ethanol-sodium dodecylsulfate is 95%.

Detection of Pharmaceuticals Using Magnetic Sers-active Core–Shell Structures

Authors: Markina N. E., Pozharov M. V., Zakharevich A. M., Burmistrova N. A., Markin A. V.

The work is devoted synthesis, investigation and application of composites based on calcium carbonate microspheres, with embedded nanoparticles of magnetite (Fe3O4), coated by silver nanostructured shell. This composite (SERS-substrate) was used for surface-enhanced Raman spectra (SERS) registration of rhodamine 6G and different pharmaceuticals such as ipratropium bromide, chloramphenicol, propranolol, pindolol, tamoxifen, diltiazem.

Definition of Arginine in the Mixed Solutions Monoaminooksidasy α-aminoacids

Authors: Varygina O. V., Chernova R. K., Petrovich M. V.

The state of monoaminooksidasy arginine and α-amino acids in aqueous media. Built chart the distribution of ionized forms of arginine and valine at varying pH. Pakistan the possibility of Express electoral pH titrations of arginine in mixed solutions monoaminooksidasy α-amino acids. The interval defined concentrations of 46,3–217,8 mg . Error does not exceed 5.5%.

Research of a State of Some the Cephalosporin Antibiotics in Water Environments by Spectrophotometry

Authors: Kulapina O. I., Karenko V. A., Kulapina E. G.

An express authenticity estimation of some cephalosporin antibiotics of II and III generations are developed by spectrophotometry. An identity of drugs such as cefotaxime (Russia) and claforan (France), cefuroxime (Russia) and cefuroxime axetil (England) is shown.

Phase Equilibria in the Twocomponent System n-nonadecan – Cyclododecane

Authors: Petrov E. P., Garkushin I. K., Kolyado A. V.

Method of low-temperature differential thermal analysis using a differential scanning calorimeter of heat flow was first studied system n-nonadecane – cyclododecane. The studied systems are of the eutectic type. Alloy of eutectic composition contains 37,0 wt % of cyclododecane and melts at a temperature of 20.4 °C.

Potentiometric Sensors for Determination of Cefepime in Water and Biological Environments

Authors: Kulapina O. I., Kulapina E. G., Karenko V. A.

Potentiometric cefepime sensors based on an organic ion-exchanger such as cefepime with tetraphenylborate are developed. The optimum membrane composition is established. The surface and volume properties of membranes are investigated. The constant of dissociation of the ion-exchanger in a membrane phase is calculated by stationary resistance. Potentiometric determination of cefepime in water and biological environments is present.

Kinetics of Cold Steel Phosphating

Authors: Mahmoud A. А., Kazarinov I. А., Trepak N. M., Isaycheva L. A.

The process of cold phosphating (25°C) of the carbon steel St3 in the zinc nitrate-phosphate system was studied using a set of physical, chemical and electrochemical methods. The electrochemical nature of steel phosphating in the given conditions was confirmed. Ways of improving the phosphating process to obtain corrosion-resistant phosphate coatings on steel were identified: modifying the phosphating solution with an inorganic silicon-containing additive and the subsequent processing of phosphate films in an aqueous solution containing silicon compounds.

Study Prior Deoxygenation Sulphurous Gases Methane and Sulhur Vapor

Authors: Ahmadov M. M., Gaкhramanova E. B., Agaev А. I.

The aim of this study was consumption is preliminary deoxygenation source of sulfur dioxide from methane-free oxygen and sulfur vapor to the catalystic’s reactor. It has been found that, the use of deoxygenated methane as agent leads to a significant increase in process speed and vaporized sulfur to improve the sulfur yield by increasing the concentration of sulfur dioxide entering in the catalyst of gaz mixture.

Simultaneous Determination of Synthetic Food Dyes E102 and E110

Authors: Shestopalova N. B., Petrovich M. V., Chernova R. K.

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%.

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

Authors: Smirnova T. D., Zhelobitskaya E. A., Danilina T. G., Nevryueva N. V.

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.

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

Authors: Sineltsev A. A., Gubina T. I.

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.

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

Authors: Cherkasov D. G., Chepurina Z. V., Kurskii V. F., Il’in K. K.

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.

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