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TEMPERATURE AS A CRITERION FOR THE DIRECTION OF EXCHANGE REACTIONS IN MOLTEN SALT OF MUTUAL SYSTEMS

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 16-33 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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ON THE RELATIONSHIP BETWEEN THE CONTENT OF CHEMICAL ELEMENTS IN RAW MATERIALS WITH DEBYE TEMPERATURE

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 34-41 p.
Abstract
The relationship between the content of heavy metals in plant raw material with such an important integral physical parameter as the Debye temperature of a metallic element is considered. This is confirmed by the high values of the correlation coefficient. This parameter is calculated for cadmium, lead, copper, manganese, nickel, chromium and zinc ions.
The graphical dependence of the accumulation coefficient k of heavy metals from the soil is presented for the wild grassy plants of the Lower Don. Wetweed ambrosia (Ambrosia artemisiifolia L.), tansy (Tanacetum vulgare L.), Austrian wormwood (Artemisia austriaca Pall. ExWilld.), Cedar grass (Elytrigia repens (L.)) are considered. Samples were taken at a distance of 1 km from Novocherkasskaya SDPP.
The value of the mobilization factor (the factor of technogenic enrichment) of EF is described as the ratio of the technogenic flow of a chemical element to a natural element, in the transfer of metallic elements. Dependences of the mobilization factor (EF) on the Debye temperature of the metal are presented.
The dependence of the heavy metals content in the soil-vegetation-invertebrate animals system in steppe biogeocoenoses on the Debye temperature of the metal is characterized. This will allow us to predict the possible mechanism for the transport of heavy metals in nature.
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RESEARCHES OF INFLUENCE OF CYCLICALLY OPERATING NEGATIVE AND POSITIVE TEMPERATURES ON THE DAMPING PROPERTIES OF CEMENT COMPOSITES

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 42-51 p.
Abstract
Results of a research of the damping properties of cement composites with various water cement relation, with additive super – and hyper softeners, fillers – ground quartz and microsilicon dioxide, quartz sands of various fineness at cyclic influence of negative and positive temperatures are given in the article. The damping properties of cement composites are determined by a resonant method. It is revealed that the studied structures of composites show changes of the damping properties at cyclic influence of negative and positive temperatures. Decrease in the damping properties is characteristic of all structures at the beginning of the researches, and then at increase in cyclic influence of negative and positive temperatures there is a further reduction or increase in an indicator. It is established that increase in decrement of fluctuations with growth of duration of an experiment is caused by de-structive processes in structure of material.
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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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