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THE ELEMENT WITH CONSTANT PHASE SHIFT IN GALVANODYNAMIC MODE

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 4-8 p.
Abstract
The purpose of this study is to study the behavior of the boundary perfectly polarized electrode – solid electrolyte in the presence of a constant phase shift impedance (CPS) in the galvanic-dynamic mode.
Analytical expressions of the dependence of the potential of the interface of an ideally polarizable electrode-solid electrolyte on time in the galvanodynamic mode in 2 cases are obtained: 1) in the case of a full equivalent electrical circuit; 2) in the case of a reduced equivalent electrical circuit. The complete coincidence of analytical expressions for the potential of the interphase boundary in both cases is shown.
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HEAVY METALS IN THE ENVIRONMENT AND THEIR TRANSFORMATION

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 9-14 p.
Abstract
The information about the presence of heavy metals in the environment was summarized. It is noted that most of them are extremely toxic, even in residues. According to the basis from various literary sources, data are presented on the properties of heavy metals to influence physical and chemical and biological interfacial interactions. It is shown that soil minerals play an important role in accelerating the abiotic processes of polymerization and polycondensation of organic compounds. At the same time, oxides of aluminum, iron and manganese are the most reactive catalysts for the conversion of many organic compounds due to their high oxidation potentials, high specific surface area and surface reactivity. Heavy metals can enter the body during breathing. When entering it heavy metals can cause various health damage including cancer, liver and kidney diseases, abortions, neurological and visual damage, a negative effect on the immune system, allergies, cardiovascular diseases and anemia. An important way for heavy metals to enter the body is through drinking water. The third way is through food with a high content of heavy metals. It is obvious that there is the urgent need to reduce the mass of heavy metals entering the environment, in water bodies with sewage in particular.
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DETERMINATION OF MERCURY IN WINE SAMPLES USING OF SILICA, MODIFIED BY POLYHEXAMETHYLENUGANIDINE

 15-20 p.
Abstract
The aim of the work was the development of a sorption-atomic-absorption method for determining mercury after its separation from wine samples in the form of a complex with unithiol on modified polyhexamethylene guanidine silica. The sorption-atomic absorption determination of mercury in wines was performed using the cold-steam method. The developed method is characterized by a low detection limit and a sufficiently high accuracy and satisfactory reproducibility.
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FRUMKIN-MELIK-GAYKAZAN MODEL IN THE CHRONOPOTENTIOMETRIC AND CHRONOAMPEROMETRIC MODES

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 4-13 p.
Abstract
This study analyzes the behavior of a metal electrode in an organic electrolyte containing a surfactant with the property of adsorption in chronoamperometric and chronopotentiometric modes.
Analytical expressions of dependence of potential of interfacial boundary metal electrode-solution of indifferent organic electrolyte on time; and also analytical relation of dependence of current passing through a cell on time in chronoamperometric mode are received.
Graphoanalytic method established that the dependence of the potential of the interface metal electrode-solution indifferent electrolyte, which has the property of adsorption on the electrode, in the Frumkin-Melik-Gaykazyan model in chronopotentiometric mode is exponential. The dependence of the current through the cell on time in chronoamperometric mode is also exponential.
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PURIFICATION OF STARCH-CONTAINING WASTEWATER

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 14-20 p.
Abstract
The paper considers the possibility of purification of starch-containing wastewater by thermally modified waste of sugar production – saturation sediment. Starchy wastewaters with a large amount of organic compounds quickly rot, create a favorable environment for the development of microorganisms, so these waters should be subjected to deep purification. Thermo-modified saturation residue (TMSR) is a fine black powder, the main component of which is CaCO3, formed during the chemical reaction between Ca (OH)2 and CO2 in saturation columns in the process of diffusion beet juicetreatment in sugar production. CaCO3 acts as a basis for the carbon layer, which covers the surface of the particles and formed during the calcination of TMSR through carbonization of organic substances contained in the original saturation sediment. The authors investigated the effect of some technological factors on the purification efficiency. It was established that 40 minutes at a temperature of the reaction medium of 20-30°C is sufficient for flow of the process. The purification efficiency of starchy wastewater systems reaches 88%.
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EXCHANGE OF MERCURY IONS IN INORGANIC ION EXCHANGERS

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 21-31 p.
Abstract
The processes of absorption and desorption of mercury (II) ions on the inorganic ion exchanger “polysurmine” (mixed antimony and silicon oxyhydrate), silicon-phosphorus-antimony ionite, and a composite material based on polysurmine and a polymeric binder are investigated. Experiments were performed under static conditions. High selectivity of polysurmine to mercury ions was shown. The relationship between the structure of ion exchangers and the sorption values achieved is shown, including the influence of a polymer binder that does not have its own ion-exchange capacity on the properties of the composite material. The desorption of absorbed mercury (II) ions from ion exchangers by various desorbents was studied and the efficiency of the latter was compared.
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PURIFICATION OF OILY EMULSIONS WITH LEAF LITTER OF CHERRY AND ROWAN

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 4-10 p.
Abstract
The paper presents the results of a study of the possibility of using leaf litter of cherries and Rowan, widely grown in Russia, for the extraction of oil of industrial grade I-20A from aqueous media. The sorption properties of cherry leaf litter and Rowan leaf litter were also studied. The bulk density, granulometric composition, humidity, pH of the aqueous extract and losses during the calcination of CLL and RLL were determined. High efficiency of purification of water-oil emulsions is established.
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INVESTIGATION OF WATER ELECTRICAL ACTIVATOR WITH COAXIAL ARRANGEMENT OF ELECTRODES

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 11-18 p.
Abstract
According to the World Health Organization, 80% of diseases are caused by poor quality of drinking water. Therefore, human life, animals, plant growth and development depend on the quality of water. Currently, when there is a continuous increase in the cost of medicines, fertilizers, pesticides, the problem of replacing the above drugs with cheaper substances is relevant. To solve this problem, it is proposed to use electro-activated water and aqueous solutions. On the basis of domestic and foreign experience, leading experts have developed methodological instructions for the widespread use and use of electro-activated water and aqueous solutions in engineering, agriculture, and medicine. For the production of electrochemically activated water and solutions, non-flowing and flow-through modular elements, as well as universal installations, were developed. Currently, a wide variety of electroactivators is offered. Analysis of the structures of these devices showed that flat metal plates are used as electrodes, therefore there are volumes of water that are exposed to uneven electrochemical effects. As a result, the specific energy consumption for obtaining activated water is significant. The purpose of the work is to reduce the specific energy consumption in the production of activated water and aqueous solutions. Coaxial arrangement of the electrodes leads to a reduction in energy consumption. Studies of the electroactivator of water with a coaxial arrangement of electrodes made it possible to establish the optimal ratio between the volumes of anolyte and catholyte and the time of electrolysis of water and an aqueous solution of sodium chloride. The results of the research can be used in the production of electroactivators for personal use as well as in industry and agriculture.
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STUDYING THE PROCESS OF OIL-CONTAINING EMULSION PURIFICATION BY MEANS OF EXPERIMENT PLANNING METHOD

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 19-30 p.
Abstract
The process of oil-containing emulsion purification with chestnut tree waste (CTW) is considered. The factors influencing the process of purification with the application of a full factorial experiment are established. The mathematical model obtained under carrying out a full factorial experiment has the form of a linear equation. The results of the calculation are comparable with the results of the experiment. The data obtained allow conducting a process of water purification at optimal values of technological parameters.
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ON THE CONCEPT OF DEVELOPING OPTIMIZED TECHNOLOGY OF OBTAINING MOLYBDATES AND TUNGSTATES OF d-ELEMENTS IN THE SOLID PHASES ON THE BASIS OF METABOLIC REACTIONS IN THE MUTUAL SYSTEMS MeSO4-Na2CO3-Mo(W)O3 WITH THEIR HEAT TREATMENT ((Me – d-ELEMENT)

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 31-39 p.
Abstract
The paper presents the material devoted to the development of the concept of optimized technology for the production of molybdenum (tungstates) elements of the d-family (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Ag) at a relatively low temperature, based on the model of a physico-chemical system, in which it is possible to form a thermally unstable intermediate phase – donor of high-defect oxide d-element, entering at the time of its formation into chemical interaction with thermally activated Mo(W)O3 with the formation of MeMo(W)O4.
In the process of solving the problem of finding the necessary to achieve the goal of the real prototypes of the chosen model of the physico-chemical system, taking into account the properties of reagents and products of their interaction, and in particular, the thermal instability of carbonates d-elements (their average decomposition temperature 3000C), it was concluded that they can be a system such as MeSO4-Na2CO3-Mo(W)O3, which was justified and confirmed in the laws of physico-chemical analysis, thermodynamics, chemical kinetics, theories of polarization of Nekrasov ions, acids and Lewis's grounds and confirmation in the experiment.
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