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2018

Archives Journal Chemical Bulletin Vol. 1

ORGANIZATIONAL AND TECHNOLOGICAL FEATURES OF PRODUCTIONS WITH COMPLEX USE OF RAW MATERIALS

 52-61 p.
Abstract
The article reveals the technological features of the processing of multicomponent raw materials, using the example of a tungsten-molybdenum deposit, which influence the construction of a cost accounting system and the calculation of the cost of production in complex productions.
It was revealed that the mineralogical composition and concentration of useful components of non-ferrous metal ores, technical conditions predetermine the transition of non-industrial ores to industrial ones. The article discusses the mineralogical features of tungsten-molybdenum ore, affecting the technological schemes of its processing. Much attention is paid to the issues of enrichment of tungsten-molybdenum ore, which allows to improve the quality of the mined ores by the content of metals and harmful impurities in them.
Considering the qualitative scheme of enrichment, showing the direction of products and the sequence of operations used in the enrichment process, as well as qualitative changes in products, you can identify the objects of cost accounting for production and costing objects.
The study showed that the structure of the production process with the integrated use of raw materials determines the organization of cost accounting for the production and calculation of the cost of the processed products, the latter, in turn, affect the objectivity of the assessment of the economic efficiency of complex use of raw materials.
Analysis of the organization and technology of processing of tungsten-molybdenum ores at mining and processing plants allowed us to identify the characteristic features of production with the complex use of raw materials, which should be taken into account when providing information and analytical support to the management of enterprises with integrated production.
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RESEARCHES OF INFLUENCE OF THE INCREASED HUMIDITY AND THE VARIABLE INCREASED TEMPERATURES ON THE DAMPING PROPERTIES OF CEMENT AGGREGATES

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 62-71 p.
Abstract
Results of a research of the damping properties of cement aggregates with different water cement relation, with the component super – and hyper plasticisers, fillers – ground quartz and microsilicon dioxide, quartz sands of different fineness in case of cyclic influence of the increased humidity and the variable increased temperatures are given in the article. The damping properties of cement aggregates are determined by a resonant method. Keeping of samples in the conditions of raised temperatures and humidity significantly influences the decrement of oscillations practically of all compositions. It is set that the damping properties of cement aggregates are defined by the damping properties of a cement stone; introduction to composition of the cement test super - and hyper plasticisers leads to lowering of this index; adding in composition of the cement test of powders of microquartz and microsilicon dioxide causes essential increase the damping properties of a cement stone with super - and hyper plasticiser.
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TEMPERATURE AS A CRITERION FOR THE DIRECTION OF EXCHANGE REACTIONS IN SALT MELTS OF MUTUAL SYSTEMS

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 4-15 p.
Abstract
The paper contains material on the current state of the problem of the orientation of exchange reactions in triple and more complex reciprocal systems in the absence of a solvent. It provides an analytical overview of the state of the problem from its inception to the end of the twentieth century, in which a critical analysis of all methods of solving it has been made for this period. As a result of numerous studies, various criteria were proposed for assessing the direction of processes in these systems, which, unfortunately, are characterized by a number of shortcomings. As a result, by the present time the problem of choosing the optimal criterion for directionality of exchange reactions in mutual systems in the absence of a solvent remains practically unresolved. The testing of the last was carried out on 53 triple mutual systems of various types for the purpose of falling out on their share of positive solutions to problems. Based on the analysis of the results obtained in this case, preference is given to the rules of Gustavson and the authors of the present work, the formulations of which are given in the text of the article.
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THE INFLUENCE OF THE METHOD OF COPPER SURFACE TREATMENT ON THE INTERACTION WITH ORGANIC LIGAND IN NON-AQUEOUS SOLVENT

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 16-18 p.
Abstract
Oxide films on the metal surface in the presence of dissolved oxygen in the organic solvent interact with the dissolved ligand to form a complex compound. The effect of preliminary treatment of the copper surface on the interaction with a ligand of salicyl alanine and α-benzoinoxime in a non-aqueous solvent of dimethylformamide and methylpyrrolidone is considered. The ligand concentration is 0.01 mol / l. The surface treatment of copper was carried out in a 12% solution of hydrochloric acid; by electrochemical deposition of copper on a copper substrate; treatment with 10% nitric acid solution; electrochemical polishing; The untreated surface of copper (spontaneous oxide and hydrocarbonate films) was used; chemical polishing; mechanical restoration; treatment with 30% and 68% nitric acid solution. The highest rate of dissolution is characteristic for samples pretreated with 12% (3,6 M) hydrochloric acid, as well as for samples whose surface was formed by electrolytic precipitation of copper from an acid solution of copper sulfate.
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ON THE CONNECTION OF THE PHYSICAL PROPERTIES OF METAL ELEMENTS WITH THE TEMPERATURE OF DEBAY

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 19-23 p.
Abstract
The article describes the relationship between the physical properties of metallic elements and the Debay temperature. This relationship is described for alkaline and alkaline earth metals. Previously, this phenomenon was observed for such parameters as density, melting point, melting enthalpy, boiling point, enthalpy of evaporation, heat capacity, binding energy of elements, coefficient of linear thermal expansion, compressibility coefficient, bulk modulus of elasticity, Young's modulus of elasticity, mineralogical hardness, surface tension, lattice parameter, internuclear distance, crystal lattice energy, electron work function, Fermi energy, atomic concentration and ionization energy. Within the framework of the study, a graphical dependence of the atomic-ion radius of the s-elements of group II on the Debay temperature of the metal is shown. For the given correlation, the following value of the correlation coefficient was observed, equal to 0,989. It should be noted that this dependence is also observed for the values of the atomic volume. The value of the correlation coefficient takes the value equal to 0,993. The interrelation between the average temperature coefficient of linear expansion of metals and the Debay temperature of an alkali metal is considered. These values are valid for the temperature range from 0 to 100°C. The correlation coefficient observed for the reduced dependence is 0,992. The dependence of the atomization energy of the crystals of the s-elements of the I and II groups on the Debay temperature of the metal is determined experimentally. The calculated value of the correlation coefficient is 0,992. The dependence of the sublimation energy of metals on the Debay temperature for metals is described. The value of the correlation coefficient is equal to the value 0,987. The correlation curves obtained will make it possible to characterize most fully the interrelation of the parameter under consideration and the above-mentioned quantities.
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METHODS OF SORPTION CONCENTRATION OF SURFACE ACTIVE SUBSTANCES

 24-30 p.
Abstract
The scarcity of water resources and their pollution speaks about the need to provide the population with environmentally safe drinking water. This problem is very relevant at the present time. Accumulating in reservoirs, surface-active substances exert a strong toxic effect on flora and fauna, impair the organoleptic characteristics of water, and hinder the processes of self-purification of water bodies. The processes of destruction of the majority of surfactants in natural waters occur rather slowly. One of the effective ways to combat water pollution by surfactants is to prevent them from entering water. Many of the techniques are laborious enough, they require expensive equipment, they are not precise enough and express. Therefore, the development of simple, rapid, accessible techniques suitable for determining the content of surfactants of different classes in soils, sewage and other objects is still an important and urgent task. The article describes methods of sorption concentration of surface-active substances with the use of inorganic residues, and with the use of natural and synthetic sorbents. In the methods of sorption concentration of surfactants with the use of inorganic residues, as precipitating agents and sorbents, oxides of calcium, magnesium, aluminum, marble chips, bischofite, magnesium sulfate can be simultaneously used. A method using electrochemical destructive oxidation is also used. Natural sorbents include various natural porous hydrophobic materials, which, due to their structure, possess considerable sorption ability. Natural sorbents are very diverse because of the difference in structure and conditions of their formation. These include inorganic products of natural precipitation reactions (bauxites, laterites, ferrolites, etc.), clays (hydroaluminosilicates), active earths (sili-cates), as well as organic precipitates and products of the transformation of organic substances of plant and animal origin (muds of lakes and seas, humus, peat, lignite, etc.). The process of application is quite expensive, which sig-nificantly reduces the economic efficiency of the use of natural sorbents.
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CONTROL OF ENVIRONMENTAL HAZARDS OF THERMAL-SOUGH PRODUCTS DETERMINING MODERN FINISHING POLYMERIC BUILDING MATERIALS

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 31-37 p.
Abstract
The results of gas-chromatographic determination of current-toxic organic substances released from finishing polymeric building materials (PBM) are presented. The products of thermal and thermo-oxidative decomposition of PBM samples based on polystyrene and polyvinyl chloride were studied. Methods for controlling the environmental hazard of degradation products of such polymers with a detection limit of 0.3-0.5 MPC values for the main ecotoxicants are developed.
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DETERMINATION OF GLUCOSE IN AQUEOUS SOLUTIONS BY VOLTAMMETRY AT THE COPPER QUASIMICROELECTRODE

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 38-44 p.
Abstract
Development of new sensors for detecting substances in different environments is now of great interest. Voltammetry methods, used in this article, allow one to carry out analysis in the field with almost no sample preparation. This study was carried out to investigate possibilities of quantitative glucose determination on copper quazimicroelectrode in aqueous solutions, including human blood. Process of preparation of copper indicator quazimicroelectrode with effective area consisting of ensemble of copper wires is described in this article. Glucose determination technique in aqueous solutions and the results of testing this electrode in quantitative determination of glycose in human blood are reported. The comparison of the results of investigated copper sensor with reference sensor is carried out. Statistically processed results of glucose determination are described. Copper advantages as electrode material are discussed. Designed electrode can find application in medical analysis laboratories and port-able devices for glucose determination in the field.
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PHASE – AND STRUCTURAL FORMATION IN THE TIO2-AL-C SYSTEM IN THE SHS PROCESS

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 4-11 p.
Abstract
The aim of the work was to develop simpler and cheaper methods of obtaining materials based on titanium carbide, which are promising for use in high-temperature electric heaters.
For this purpose, a composite material based on titanium carbide and alumina with the use of titanium oxide, aluminum and soot as the starting components was obtained by self-propagating high-temperature synthesis. It has been established that the main stages of the synthesis process are the melting of the initial titanium and aluminum oxide, the reduction of titanium oxide by aluminum, the interaction of the reduction product of titanium oxide with carbon. The flow of a side reaction of reduction of titanium oxide by carbon can cause the formation of non-stoichiometric titanium carbide.
The additions of carbon, aluminum, titanium, manganese zirconium nickel and silicon to the phase composition, microstructure, electrical conductivity of the synthesis product, the degree of stoichiometry of titanium carbide were studied. Addition of carbon up to 10 wt. % increases the burning rate of the initial mixture, and the lattice parameter of the titanium carbide. The addition of carbon and manganese in excess of the stoichiometry allows a more complete flow of the process and allows improving the quality of the product due to a more complete removal of oxygen from the titanium carbide and increasing the specific conductivity of the resulting composite.
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ESTIMATION OF THE INFLUENCE OF THE STATE OF THE REINFORCING POLYMER IN THE STRUCTURE OF POLYMERIC FIBER MATERIAL USING MATHEMATICAL PREDICTION METHODS

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 12-17 p.
Abstract
The most difficult technological problem in the production of garments is the creation of the required complex geometric shape and ensuring its safety during operation. It is promising to carry out developments aimed at justi-fying methods for increasing the elastic-deformation properties of a garment package by forming three-dimensional self-organizing structures of a reinforced polymer-fiber composite (PFC) in the main material or a duplicating web. PFC is formed when a polymeric binder penetrates, as which polyacrylate, polyurethane and other dispersions can be used, into the interporous and nanopores space of the fibrous material. At the same time, the possibility of fine adjustment of the stiffness and elasticity parameters is provided by scientifically justified selection of components and application of complementary variants of nanoengineering of the interphase layer. An experimental estimation of the dispersion state of the prospective assortment of preparations as well as the effect of the dispersion degree of the binder on the basic elastic-deformation properties of PFC samples was carried out. It is established that the penetration of the reinforcing polymer component into the submicroscopic pores of the textile carrier is a techno-logically necessary condition for the organization of interfacial interaction in the structure of the composite material ensuring the provision of the cushioning material with the required set of functional properties: increasing rigidity while maintaining high resistance to crushing. The microlevel of the particle size of polymer dispersions determines the surface distribution of the reinforcing polymer with penetration into the inter-fiber spaces, which contributes to the formation of a rigid but brittle film that breaks down when a test crushing load is applied. An effective method of preliminary ultradispersing of reinforcing polymer dispersions is the use of cyclic rotor-pulsation influences with pauses of cooling the treated system to room temperature.
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