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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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TO AN ASSESSMENT OF SIZE OF DIFFUSIVE LOSSES OF COOLANT THROUGH A RUBBER CAMERA – COVER

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 18-26 p.
Abstract
In the article the calculation of time of technologically admissible volume of losses of coolant due to diffusive permeability through walls of cameras of branch pipes of refrigerators with the given technical characteristics is executed. The guaranteed resource of work of branch pipes was 14,1 and 7,4 years respectively for one and second machines. Experimental researches of influence of type and structure of fillers on diffusive permeability are carried out on rubbers: 61-202 on the basis of a chloroprene of S-40 and RK-1802 on the basis of the hydrogenated ZETPOL-2000 rubber, at the acceptable technological indicators of processing and production of rubber cameras. The optimum share of filling of rubber mix is experimentally chosen – 20% of mass parts as ground mica. For ensuring long resistance of rubber to influence of coolant as basic it is recommended to use ZETPOL-2000 brand rubber hydrogenated.
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SORPTION-PHOTOMETRIC DETERMINATION OF ANIONIC SURFACTANTS IN THE PRESENCE OF ORGANIC REAGENT

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 27-36 p.
Abstract
The article describes the characteristics of a class of surfactants and the use of substances in the petrochemical industry. The classification of anionic surfactants is considered. The main structural elements of the structure of substances of the considered class are presented. A brief description of the most commonly used methods for the analysis of anionic surfactants is given. Advantages of using photometric, extraction-photometric and spectrophotometric methods for the determination of anionic surfactants using triphenylmethane dyes are described. In the course of the study, the content of the anionic surfactant (sulfonol) in the solution was monitored spectrophotometrically using the indicator reaction with malachite green. The use of the method in question to study sorption processes in a surfactant system is justified by the fact that surfactants are able to form complex compounds (ionic associates) with organic reagents with characteristic light absorption bands.
The results of a photometric determination of an anionic surfactant (sulfonol) using an organic reagent, malachite green, are presented. The effect of the acidity of the environment on the process of adsorption of a component in aqueous solutions is described. A calibration graph for determining the concentration of the component is given.
The main thermodynamic parameters of sulfon adsorption on activated carbon, such as enthalpy (∆H), isobaric-isothermal potential (∆G) and entropy (∆S) sorption were determined during the research. The obtained research results can be used for quantitative determination of the component and modeling of adsorption mechanisms.
The main characteristics of the sorption kinetics of a surfactant (sulfanol) on active coal are calculated. Isotherms of sorption kinetics are given. The possibility of purification from the above-described component using the sorbent under consideration is described.
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APPLICATION OF NANOFLUIDS IN REFRIGERATING ENGINEERING

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 37-40 p.
Abstract
Еlectricity consumption by refrigeration equipment is about 20% of the total energy consumption. Ways to improve the efficiency of refrigeration units is one of the most urgent tasks in the light of the general policy of energy saving in the world. The efficiency coefficient of refrigeration machines depends on the efficiency of heat exchange in the system. In addition to the obvious ways to improve the design of the refrigeration circuit itself, there are a number of alternative solutions to improve the energy efficiency of heat exchange processes. Among them there is the addition of metal oxide nanoparticles to the circuit, which have a high heat transfer coefficient. The article presents a review of the literature on the use of nanoparticles in cooling systems, which describes the energy efficiency from 9.6% to 28% depending on the material of nanoparticles and their concentration. Also, an experimental re-frigeration unit was manufactured, where copper oxide nanoparticles in a concentration of 1% were used. This installation showed a decrease in electricity consumption by 18%, as well as a better dynamics of temperature de-crease.
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ABOUT CONNECTION OF LIQUACTION WITH THE DEBYE TEMPERATURE

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 41-46 p.
Abstract
The article describes the concept of liquation. Within the framework of the research, the definition of the concept described is given. The types of liquation (zonal and dendritic) are given. It is established that a number of parameters characterizing the segregation process are related to the characteristic Debye temperature of a chemical element. The interrelation between the values of the effective atomic radius, intensity, and also the liquation coefficient from the Debye temperature is considered. The role of the values of the maximum supercooling parameter on the Debye temperature is described. The dependence of the content of elements in interdendritic volumes on the Debye temperature is considered. The dependence of the chemical composition of local regions on the Debye temperature is given. A similar trend was observed with the values of the viscosity of the molten metal. The correlation coefficients always exceeded 0.9.
It should be noted that the liquation process adversely affects the steel properties. This can affect the values of the toughness of transverse specimens. The considered dependences of the process parameters can be useful for describing the processes of eliminating the heterogeneity of steels. All this will not only improve its properties, but also describe in more detail the process of eliminating the chemical heterogeneity of steel. In addition, this will allow us considering the melting process with a change in volume. Increased interest causes the content of elements in the axes of the dendrites in the initial cast state. It was found that the distribution of elements in the axes of dendrites in interdendritic microvolumes in the structure of the pressed steel does not depend on the quenching method. For the dependence considered, the values of the correlation coefficient are calculated. The main conditions of the quenching process as well as the content of the elements in percent are given.
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