02.00.00 Chemical sciences
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Description
The аrticle is devoted to study of adsorption of enzymes, antioxidants contained in horseradish root on starch to create enterosorbent with anti-oxidant properties. For this goal we have studied adsorption isotherm calculated constants, thermodynamic parameters (change of enthalpy, entropy, and isobaric-isothermal potential); sorption kinetics of enzyme-antioxidants on starch and calculate the main characteristics. The method of producing of enterosorbent - antioxidant on based starches has been developed based on the experimental data. The ready sorbent is a white powder having no taste and smell. In biological fluids and water, it is insoluble. The enterosorbent on starch does not dissolve in water and biological fluids. It is the solid component. This enterosorbent can be used to protect the gastrointestinal tract of humans and animals against a wide variety of oxidants and peroxide. The results of this work will form the basis for the study of the antioxidant properties of the resulting enterosorbent. The results showed that during the tests, the enterosorbent on the starch showed good antioxidant properties. It has high antioxidant activity with respect to hydrogen peroxide
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RESEARCH IN MICRODEFICIENCY OF POLYMERS (ELASTOMER COMPOSITIONS) UNDER UNIAXIAL DEFORMATION
DescriptionMacrodeficiency of polymeric materials, including the pervasive one, is a consequence of the development of initial microdefects which appear in polymers both due to external factors and during their processing. This article solves the task of identification the interrelation and interdependence of structural microdefects of various polymeric materials, consisting in the estimation of the structural parameters under uniaxial deformation. It is experimentally shown that the process of changing microdefects in the material bulk begins to flow more intensely during deformation of the material, having anisotropic structures in the bulk. Change of the parameters of microdefects is not observed compared to the starting material at small quantities of the deformation. In the area of deformation corresponding to the transition of the material from isotropic to anisotropic state parameters of microdefects do not depend on the degree of deformation of the sample, and abrupt changes of the parameters of microdefects are observed after completing the formation of anisotropic patterns. It is shown experimentally the identity of the parameters of microdefects in the bulk material (rubber-based natural caoutchouc) during deformation with the quantities of local deformations at the edge of the artificially created macrodefects. Under uniaxial deformation more than 280-300% and the growth of the quantities of local deformations come out at the edge of the artificially created macrodefects and normalized linear dimension k and decrease the total number n of microdefects
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Description
Theoretically and experimentally, we investigated the process of adjusting the pH of natural water of hydrocarbonate class electrodialyzer with bipolar membranes with channel length of 40 cm. We experimentally measured concentration of components, pH of the solutions in alkaline and acid channels of electrodeposition depending on the current density. The article describes a mathematical model for long channels; to scale the mass transfer characteristics of the process there was applied and verified a method of compartmentalization, which gave the possibility to calculate the dependence of the component along the channel length at different velocities of flow of the solution. Numerical calculations were compared with experimental data on electrodialyser of 10 cm and 40 cm length
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DEVELOPMENT OF A METHOD FOR FIXING PERFTORSULFOPOLIMER MF-4SK ON A HETEROGENEOUS MEMBRANE-SUBSTRATE
DescriptionThe article illustrates the results of the research dedicated to finding a method of combining two polymeric materials - ion-exchange membranes having different chemical nature. It shows a method of applying a homogenous film MF 4SK on the surface of the heterogeneous membrane substrate to produce a chemically and mechanically stable asymmetric bipolar membrane. We have selected membrane substrate ensuring the best electrochemical performance
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ELECTRICAL CONDUCTIVITY OF IONEXCHANGE MEMBRANES IN SOLUTIONS CONTAINING CARBOXYLIC ACIDS
DescriptionThe article presents the experimental results of the study of the concentration dependence of the electrical conductivity of heterogeneous ion-exchange membranes that are in contact with solutions of weak electrolytes - carboxylic acids. It is shown that in this case the membrane conductivity is higher than the conductivity of the solution, wherein the conductivity of cation exchange membranes substantially greater (by an order of magnitude) than the conductivity of anion exchange membranes. This fact must be considered when designing the actual electrodialysis processes of processing solutions containing organic ions. The work identified the need to develop modern ideas about transport and the structural organization of ion-exchange materials, to describe the structure of the ion-exchange membranes that are in contact with weak electrolytes solutions
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Description
The present work describes the chemical synthesis of poly-N,N-diallyl pyrrolidinium bromide and polyN,N-diallyl morpholinium bromide - high-molecular compounds containing quaternary nitrogen atoms, which included in two five- and/or six-membered heterocyclic rings. These polymers are perspective modifiers for industrially produced anion-exchange membranes, the use of which should significantly improve the resistance to degradation of the membranes at over-limiting current regimes. The structure of obtained polymers was characterized by FTIR, 1H and 13C NMR spectroscopy. The optimal reaction conditions, which increase the yield of desired products, were defined. It is shown that is preferable to use 1-butanol as a solvent and benzoyl peroxide as an initiator
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SYNTHESIS OF SUBSTITUTED ISOXAZOLO[5,4-b]PYRIDINE AND THEIR ANTIDOTE ACTIVITY
DescriptionTo develop the novel herbicide antidotes for the sunflower vegetative plants, the group of chemical compounds, belonging to the derivatives of isoxalopyrazolopyridines was synthesized and their antidote activity both in the laboratory and field experiments was studied. The compounds with a high antidote effect were found
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INVESTIGATION OF ASCORBIC ACID ADSORPTION ON KSMG SILICA GEL
DescriptionThe article studies adsorption of ascorbic acid on KSMG silicagel. The experimental results, the basic thermodynamic characteristics of ascorbic acid adsorption on oxide silicon have been used for treatment of adsorption mechanism of ascorbic acid on silica KSMG. Results of the study ascorbic acid adsorption on silica gel KSMG may be used for further identification of it in the various objects
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Description
Macrodeficiency of polymeric materials, including the pervasive one, is a consequence of the development of initial microdefects which appear in polymers both due to external factors and during their processing. In the article, the problem of the detection of structural microdeficiency of various polymeric materials through an assessment of their structural parameters is solved. The considered materials possess approximately identical degree of crystallinity (60 – 66%), but different density. The express assessment technique of polymeric materials microdeficiency by the sorption method with the use of the academician M. M. Dubinin’s theory of volumetric micropore filling is developed and evaluated. On the basis of a quantitative assessment of sorption processes in polymeric materials, including elastomeric compositions – rubbers and rubberized fabrics, the existence of the initial local microdefects arising in the course of synthesis is established. In real polymeric materials, including elastomeric compositions – rubbers and rubberized fabrics, the existence of the initial local microdefects arising in the course of synthesis is established (the number of microdefects n varies from 1x1017 sm-3 to 6x1019 sm-3 , and the rated linear size k – from 2 nm to 7 nm). The general reduction of microdeficiency in rubberized fabrics in comparison with initial rubber is revealed and rationalized
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STUDY OF THE INTERACTION OF POLYSTYRENE-AZO-O-PHENOL-AZO-RHODANINE WITH ZINC IONS AND CADMIUM
DescriptionSince the industrial revolution a huge amount of pollutants emitted annually into the water most of which is occupied by toxic metals. These metals widely distributed in the environment and of accumulation of a threat to human health. It is known, that cadmium and zinc at high concentrations have a negative impact on nature. In modern wastewater treatment technology we widely use polymeric sorbents with chelating properties. The use of polymeric chelating sorbents (PCS) usage allows separating individual or group trace elements from large volumes of solutions of complex composition, lowering the limit of detection, eliminating or reducing significantly the impact of macrocomponents which increases the cleaning efficiency. The article presents the results of a study of conditions of interaction of zinc (II) ions and cadmium (II) with PCT - polystyrene-azo-o-phenol-azo-rhodanine. We found the optimal values of the conditions for zinc (II) ions and cadmium (II) sorption. We investigated the effect of interfering of the macro- and micro- water components with the sorption of the ions studied. Maximum desorption of metal ions is achieved by washing the concentrate with 10 ml of 2M hydrochloric acid. The data indicate availability of the investigated sorbent for concentration and separation of zinc (II) ions and cadmium (II)