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Vol. 1 Issue 2

Archives Journal Chemical Bulletin Vol. 1 Issue 2

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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