02.00.00 Chemical sciences
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NI, CR, PB IN HYDROMORPHIC SOILS OF THE TEREK-SULAKSKOY SUBPROVINCE OF DAGESTAN
Description
In the article, we investigated hydromorphic soils of the Tersko-Sulak subprovince of Dagestan. We determined the content of humus, nickel, chromium and lead with genetic horizons of the investigated soils. The small excess of the maximum allowable concentration of nickel and chromium has been found, doze of lead was within norm
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ALTERNATIVE MODEL OF CALCULATIONS OF VALUES OF ATOMIC RADIUS
Description
The article presents the results of the development of an alternative model for calculating the values of atomic radius. A formula was derived for calculating the atomic radius of the elements of the Periodic System of DI Mendeleev. The optimal calculation conditions for the proposed model are found. It is shown that the curve of the dependence of the value of the correction coefficient x on the atomic number of the element in form coincides with the dependence of the ionization energy on the charge number
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Description
Studying natural phenomena in all their diversity, humanity worked experienced in every field of science the model of perceiving the world and methods of obtaining information. The development of science currently cannot be imagined without research on the intersection of its regions. This article presents the results of the automated systemcognitive analysis of the size of atoms from the main characteristics that are of research at the interface of General chemistry elements and intelligent systems. Dependence of nuclear radius, mass and of the atom and the charge number are identical in shape and size, which is probably connected with the linear increase of these parameters in the Periodic system of chemical elements. There is also a similar form of the dependences of radii of atoms from the factors ex and x, because these factors are interrelated. The obtained results of the ask analysis have confirmed the theoretical assumptions and the formulae of the dependence of main characteristics of the atom
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INTERRELATION OF THE MODEL OF CALCULATIONS OF ATOMIC RADIUS AND VARIOUS SYSTEM CHARACTERISTICS
Description
In this article, we discuss the relationship between the previously obtained model for calculating atomic radii with electrodynamics, the hydrodynamic model of the planets of the Solar System, and the R-function of the structural organization of electronic systems. It is shown that the curve of the dependence of the value of the correction coefficient e x on the atomic number of the element in form coincides with the dependence of the ionization energy on the mass of the atom and the R-function on the nuclear charge. The concept of the "atomic nucleus potential", which takes into account the energy of the nucleus and the charge of the nucleus of the atom, is introduced. It is shown that the radius of an atom is the product of the nuclear potential by a factor kx , taking into account the characteristics of electronic levels; the energy of the nuclear reaction is the work of the forces of the field (potential) of the atomic nucleus along the displacement of the atomic charge. The dependence of the potential of the nucleus on the charge number in the Mendeleev’s Periodic Table is shown. It is shown that any system of satellites (or atomic shells) has a constant ratio of its Kepler number to the mass of the central body around which they rotate. It is shown that in the Table of Mendeleev's chemical elements and in the solar system, the fundamental value is the mass of the center (the nucleus of the atom or the center of the orbit). The ratio of the Kepler number to the mass of the central body is a constant, within the accuracy of construction and calculations
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INFLUENCE OF HEAVY METALS HYDROXIDES ON WATER DISSOCIATION IN BIPOLAR MEMBRANE
Description
The results of study of bipolar membrane – analogue of MB-2, modified with chemically introduced chromium (III), iron (III) and nickel (II) hydroxides by the method of frequency spectrum of electrochemical impedance, by infrared spectroscopy and scanning electron microscopy in combination with X-ray spectrum analysis are presented. It is shown, that sequential treatment of cation-exchanger, contained in cationexchange membrane, with metal salt solution and alkali solution does not result in formation of complex compounds of these metals with ionic groups of ion exchanger. It was found that in these conditions the presence of heavy metals in the phase of cationexchanger confirmed by X-ray analysis, however, crystals of hydroxides of heavy metals are not detected in the size range of 1000 nm to 20 nm. These heavy metal compounds are thermally unstable and their catalytic activity in the reaction of dissociation of water molecules decreases with increasing temperature during heat treatment. The introduction of low-soluble hydroxides of d-metals (chromium (III), iron (III), nickel(II)) by chemical method can significantly improve the electrochemical characteristics of a bipolar membrane. The most effective catalysts in water dissociation reaction are the hydroxides of chromium (III) and iron (III) and, as a consequence, membranes with these hydroxides have a lower value of overpotential compared with original membrane at the same current density
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INFLUENCE OF ORGANIC SOLVENTS ON WATER DISSOCIATION IN BIPOLAR MEMBRANE
Description
The article discusses results of experimental research of the influence of aprotic and proton solvents on reaction rate of water molecules dissociation in the bipolar membrane MB-1 by the method of electrochemical impedance frequency spectrum. It was discovered, that addition of organic component in aqueous solutions results in significant influence on the parameters of water dissociation in a bipolar region of the membrane. The reason for this influence is the reduction of the mass fraction of water in solution and, consequently, in a bipolar region of the membrane, which itself reduces the rate of the dissociation reaction. Another reason for the influence of the organic solvent is its effect on the network of hydrogen bonds existing in water and aqueous solutions. Depending on the nature of organic solvent and its concentration, the network of hydrogen bonds may be strengthened, or destroyed, thus facilitating removal of the proton involved in the reactions between water molecules and catalytic centers in cation-exchange and anion-exchange layer of bipolar membrane, or retarding removal of proton. This leads respectively to speed up or slow down the rate of dissociation in the bipolar region of the membrane, as well as changing the constants of the dissociation reaction of water. Introduction of organic solvent in solutions, which are in the contact with bipolar membrane, is a convenient method of investigating the role of solution composition on the rate of proton transfer between water molecules and catalytic centers in the membranes
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Description
Particular qualities of growth of homofermentative lactic acid producer Lactococcus lactis CH5 depending on the composition nutrient medium: glucose and yeast autolysate concentration are examined in the article. The influence of the method of cultivation on the productivity and the speed of the lactis acid synthesis is analyzed
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Description
The current-voltage characteristics and the number of effective ion transfer, as well as the frequency spectrum of the electrochemical impedance of multilayer ion-exchange membranes in a stable and controllable thickness of the diffusion layer were measured, using the of rotating membrane disk complex. The article presents a comparative analysis of the frequency spectra of the electrochemical impedance of the source and a surface-modified monopolar anion exchange membranes in 0.01 M sodium chloride was made. The process of water molecules dissociation at current densities above the limiting one in 0.01 M sodium chloride solution was studied in detail
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THE DIPOLE MOMENTS AND THE STRUCTURE OF THE FOUR-MEMBERED CLOSED-CHAIN ARSENIC COMPOUNDS
Description
By the method of dipole moments, there has been determined that the tri-coordinated arsenic derivatives (p-XC6H4AsN-R)2 with R= Bu-t in the liquor exist in a cis-form, as for R=С6Н4Х-p the trans-structure is being realized. As for tetra-coordinated derivatives [XC6H4As(S)NBu-t]2 the trans-form is also beeing observed. For ortho-substituted connections, the angles of flat surfaces rotation of benzene rings have been defined
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Description
This publication examines the relationship between the structure of molecules of complexing (descriptors of electronic structure), which are used as inhibitors of hydrogen embrittlement of the steel grade St3, and the content of absorbed hydrogen in model samples-plates made of the above steel. The form of expression of this relationship is the correlation coefficient (CC) by Pearson
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