Chemistry

Equilibrium Liquid–Liquid–Solid and Critical Phenomena in the Quaternary System Cesium Nitrate+Water+Pyridine+Butyric Acid with in the Range of 5 to 60°C

Phase equilibria and critical phenomena in the component mixtures of a cut of the composition tetrahedron of the quaternary system cesium nitrate + water + pyridine + butyric acid were studied in the range of 5–60°C by the visual-polythermic method. The phase equilibria in the component mixtures were studied using sections of one cut of the composition tetrahedron. The cut position was chosen in such a way as to cross all figures of the phase states with the presence of a solid phase in order to observe the phase behavior of the monotectic state figure as temperature changes.

Antioxidant Status of Macrobasidiomycetes Mycelium Grown in the Presence of Organoselenium Compounds

Antioxidant status maintenance plays a significant role for mushroom cultures in respect to oxidative stress resistance, cytodifferentiation and transition to the generative stage. Strong antioxidants are the selenium compounds. One of the antioxidant action indices is the antiradical activity determined by means of the spectrophotometric method using the reactions with the free radical 1,1-diphenyl-2-picrylhydrazyl (2,2-diphenyl-1-picrylhydrazyl, N,N-diphenyl-N’-picrylhydrazyl, DPPH) (C6H5) 2N– N•–C6H2(NO2) 3-2,4,6.

Chemometric Method of PLS in the Treatment of Titrimetric Data when Opredeleniye of Arginine and Lysine in Mixed Solutions

Arginine and lysine are the most important α-amino acids that are part of many proteins, which play an important role in the processes of nitrogen metabolism, growth and restoration of body tissues. It is used in medical nutrition in the postoperative recovery period, as well as as diagnostic factors. The simple express methods of separately determining the main α-amino acids of arginine and lysine in their mixed solutions are in demand.

Screen-printed Potentiometric Sensors for Cefuroxime Axetil Determination in Small Sample Volumes

Potentiometric screen-printed cefuroxime axetil sensors were developed. The optimum membraneand carbon ink compositions were determined. The main sensor electroanalytical and operational characteristics were evaluated. The sensors were used to determination of cefuroxime axetil in small sample volumes of model water solutions and mixed saliva (oral fluid). Upgrading sensor designs opens up new sensor application for pharmaceutical kinetic antibiotic studies on the mixed saliva analysis and correction treatment of various pathological processes.

The Determination of Biological Effects of New Heterocyclic Compounds on Plants and the Evaluation of Environmental Safety of Their Application

Еcotoxicological evaluation of two new polyheterocyclic compounds was spending. Acute toxicity of test substances, their lethal and safe concentration (LC and BC) were determined. The nature of the biological effect of these compounds on the plants was investigated. The substances were stimulants during the germination of seeds of wheat and peas and inhibitors of the growth of the roots and stems of seedlings. It was determined the effect of various concentrations of tested compounds on the growth characteristics of plants.

Investigation of the Structure and Ways of Formation of Isomeric Tyenylsubstituted Triazolohexohydroquinazolines by Methods of NMR Spectroscopy and Chromato-mass-spectromectry

In the three-component condensation of thiophenecarbaldehyde, cyclohexanone and 3-amino-1,2,4-triazole triazolohexahydroquinazolines are formed, which are isomeric in the type of the ring junction and the double bond position in them, the structure of which is established by 1H NMR spectra. With the GC-EIMS-analysis of the composition of the reaction mass at various temperatures, it has been established that an intermediate in the formation of final products is azomethine (instead of a possible α,β-unsaturated ketone).

Synthesis and Structure Mixedligand Complexes of Fe, Co and Ni with Dimerkaptophenols and Heterocyclic Diamines

Physico-chemical methods investigated complexing Fe (II, III), Co (II) and Ni (II) with di mer kap tophenols (2,6-dimerkaptophenol, 2,6-dimercapto- 4-methylphenol, 2,6-dimercapto-4-ethy l phenol, 2,6-dimercapto-4-propylphenol and 2,6-dimercapto-4-tert-butylphenol), and hyd rophobic amines. The hydrophobic amine were used as heterocyclic diamine- 1,10-phenan thro line, 2,2’-bipyridyl and 4,7-diphenyl-1,10-phenanthroline (batofenantrolin). The optimal conditions for the formation and extraction mixedligand complexes and set the ratio of the components in the complexes.

Моделирование осушки природного газа при давлениях 20–25 МПа алюмогелем и цеолитом NaA 4A

Пары воды, содержащиеся в природном газе, препятствуют его нормальной транспортировке и применению в качестве топлива внутреннего сгорания. Наиболее перспективной технологией осушки газа является адсорбция при высоком давлении. Важной задачей является оптимизация процесса при помощи построения математической модели.

Фазовые диаграммы тройных систем карбонат калия – вода – углеводород при 25°с

Методами сечений и изотермического титрования при 25°С впервые изучены фазовые диаграммы тройных систем карбонат калия – вода – углеводород (толуол, н.додекан). Фазовые диаграммы обеих систем относятся к диаграммам тройных системс высаливанием двойной гетерогенной системы. Твердой фазой монотектического равновесия является полутораводный кристаллогидрат карбоната калия. На поле расслоения фазовой диаграммы каждой тройной системы построено девять нод.

Экспериментальное изучение растворимости гелия в пропан-2-оле при температурах 360, 420 и 480 к

Произведено экспериментальное изучение растворимости гелия в пропан-2-оле при высоких давлениях и температурах. Получены следующие значения констант Генри для раствора гелия в пропан-2-оле: 168,7 ± 6,3 МПа при 480 К, 341,2 ± 13,6 МПа при 420 К и 602,0 ± 43,5 МПа при 360 К.
 

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