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The paper summarizes the results of numerous works performed by the employees of the Pobuzky Ferronickel Plant, the Department of Electrometallurgy of the USU of Science and Technology (Dnipro), RPC "Technosplavy" under the leadership of Mykhailo Hasyk, academician of NASU. A technology of low iron recovery has been implemented at the plant, which allows producing high-percentage black ferronickel, containing 30-50 % Ni, and almost hundredth fractions of carbon and silicon, directly in electric furnaces. The thermodynamic features of out-of-furnace ladle desulfurization of ferronickel with soda are considered. A complex technology has been developed and implemented, which involves mixing black ferronickel with a reduced silicon and carbon content (up to 0.01 %) and a high nickel content (over 50 %) produced in one furnace with an alloy from another furnace with a low nickel concentration (10-17 %) and a high concentration of silicon and carbon, which are so necessary for desulfurization with soda in a ladle. The developed and proposed technological schemes for the enrichment of electric furnace slags using the "wet" technology and refining slags using the "dry" technology make it possible to recycle about 1,200 tons of nickel per year, or to extract 31.6 % and 94.65 % of nickel from the slags, respectively. [ABSTRACT FROM AUTHOR]

The analysis of main published results of studies of retention and migration of ion-implanted hydrogen isotopes and helium in tungsten and tantalum coatings, formation of radiation damages of the crystal lattice and their interaction with implanted gases, as well as the influence of helium and deuterium on various properties and surface morphology of coatings was carried out. The irradiation of samples was performed by beams of accelerated ions of hydrogen isotopes or He+, and in a plasma containing these ions, at various fluences and energies of incident ions, and at various temperatures of targets during implantation. Special attention was paid to the research results obtained at simultaneous irradiation of W both in bulk and in thin-film form. The used methods were electron microscopy, reemission mass spectrometry, thermal desorption spectrometry, X-ray photoelectron spectroscopy, X-ray diffraction, nuclear reaction analysis and Rutherford ion scattering. [ABSTRACT FROM AUTHOR]

The paper examines the issue of improving the methods of identification of economic objects and their analysis using algorithms of intelligent data processing. The use of the developed methodology in the economic analysis allows for improvement in the quality of management. It can be the basis for creating decision support systems to prevent potentially dangerous changes in the economic status of the research object. In this work, an improved method of c-means data clustering with agent-oriented modification is proposed, and a radial-basis neural network and its extension are proposed to determine whether the obtained clusters are relevant and to analyze the informativeness of state variables and obtain a subset of informative variables. The effect of applying data compression using an autoencoder on the accuracy of the methods is also considered. According to the results of testing of the developed methodology, it was proved that the probability of incorrect determination of the state was reduced when identifying the states of economic systems, and a reduced value of the error of the third kind was obtained when classifying the states of objects. [ABSTRACT FROM AUTHOR]

The reactions of potassium dichlorodicyanoaurate with n-propyl-, iso-butyl-, and n-heptyltriphenylphosphonium bromides in water followed by recrystallization from acetonitrile give dichlorodicyanoaurate complexes [Ph3P(n-Pr)][Au(CN)2Cl2] (I), [Ph3P(i‑Bu)][Au(CN)2Cl2] (II), and [Ph3P(n-Hp)][Au(CN)2Cl2] (III). Compounds I−III are identified by elemental analysis and IR spectroscopy. The structure of compound III is also proved by X-ray diffraction (XRD) (CIF file CCDC no. 2094701). According to the XRD data, complex III consists of n-heptyltriphenylphosphonium cations and crystallographically independent planar square dichlorodicyanoaurate anions of two types with similar geometric parameters. The steric organization of the crystal of complex III is formed by hydrogen bonds С–H∙∙∙N≡C (2.55–2.63 Å) and С–H∙∙∙Cl–Au (2.87 Å). In addition, the structure contains С–H∙∙∙π(Ph) contacts with the distances from the hydrogen atom to the benzene ring plane equal to 2.80 Å. [ABSTRACT FROM AUTHOR]

The reactions of potassium dichloro- and dibromodicyanoaurate with appropriate ethyl and (2‑bromoethyl)triphenylphosphonium halides in water gave new dihalodicyanoaurate complexes [Ph3PE-t][Au(CN)2Cl2] (I) and [Ph3PCH2CH2Br][Au(CN)2Br2] (II), which were characterized by X-ray diffraction (CCDC nos. 1963511 (I) and 2060274 (II)). According to X-ray diffraction data, complexes I and II consist of tetrahedral organyltriphenylphosphonium cations and two types of crystallographically independent square planar dihalodicyanoaurate anions with similar geometric parameters. The phosphorus atoms in the phosphonium cations have a slightly distorted tetrahedral coordination. The centrosymmetric crystallographically independent anions [Au(CN)2Cl2]– in I have a nearly undistorted square planar geometry, whereas the geometry of the [Au(CN)2Br2]– anions in II is substantially distorted (the CAuBr cis-angles vary in the range of 74.5(9)°–105.5(9)°). The spatial organization in the crystals of I and II is formed by the C–H∙∙∙N≡C hydrogen bonds and, in the case of complex II, also by additional inter-ion C–H∙∙∙Br–Au contacts. [ABSTRACT FROM AUTHOR]

The reactions of potassium dichloro- and dibromodicyanoaurate with appropriate ethyl and (2‑bromoethyl)triphenylphosphonium halides in water gave new dihalodicyanoaurate complexes [Ph3PE-t][Au(CN)2Cl2] (I) and [Ph3PCH2CH2Br][Au(CN)2Br2] (II), which were characterized by X-ray diffraction (CCDC nos. 1963511 (I) and 2060274 (II)). According to X-ray diffraction data, complexes I and II consist of tetrahedral organyltriphenylphosphonium cations and two types of crystallographically independent square planar dihalodicyanoaurate anions with similar geometric parameters. The phosphorus atoms in the phosphonium cations have a slightly distorted tetrahedral coordination. The centrosymmetric crystallographically independent anions [Au(CN)2Cl2]– in I have a nearly undistorted square planar geometry, whereas the geometry of the [Au(CN)2Br2]– anions in II is substantially distorted (the CAuBr cis-angles vary in the range of 74.5(9)°–105.5(9)°). The spatial organization in the crystals of I and II is formed by the C–H∙∙∙N≡C hydrogen bonds and, in the case of complex II, also by additional inter-ion C–H∙∙∙Br–Au contacts. [ABSTRACT FROM AUTHOR]

Ionic gold(III) complexes [Ph3PMe][Au(CN)2Cl2] (I), [Ph3PCH2Ph][Au(CN)2Cl2] (II), [Ph3PC6H11-cyclo][Au(CN)2Br2] (III), and [Ph4P][Au(CN)2I2] (IV) are synthesized by the reactions of organyltriphenylphosphonium halides with the corresponding potassium dihalodicyanoaurates in water followed by the recrystallization of the reaction products from acetonitrile or DMSO. The complexes are characterized by X-ray diffraction (XRD) (CIF files CCDC nos. 1901681 (I), 1912903 (II), 1912919 (III), and 2048146 (IV)) and IR spectroscopy. According to the XRD data, the crystals of complexes I–IV consist of centrosymmetric square-planar anions [Au(CN)2Hal2]– and organyltriphenylphosphonium cations with a slightly distorted tetrahedral coordination of the phosphorus atoms. The structural organization in the crystals of complexes II–IV is formed by interionic hydrogen bonds С–H∙∙∙N≡C, whereas no significant interionic contacts are observed in the crystals of complex I. [ABSTRACT FROM AUTHOR]

Changes in the composition of chemical compounds on the surface of a polycrystalline Zr2Fe alloy sample upon its interaction with oxygen, as well as the effect of oxygen on the processes of alloy interaction with hydrogen are studied using the secondary ion mass spectrometry technique. The interaction of oxygen with the alloy sample is shown to cause the formation of a complex oxide structure containing zirconium, iron, and oxygen on the surface and in the surface region. The ratio of the number of oxygen atoms to that of metal atoms in the oxides increased with increasing oxygen partial pressure. When the alloy is exposed to a hydrogen-oxygen gas mixture, a chemical structure that includes oxides, hydrides and hydroxides of alloy components is formed on the surface. The amount and composition of the compounds formed depend on the ratio of the hydrogen and oxygen fractions in the gas mixture, although the formation of oxides prevails over the formation of hydrides. Hydrides of the alloy components, mainly zirconium hydrides, are formed on surface sites that are free from oxides and hydroxides. At a fixed value of the oxygen partial pressure, an increase in the hydrogen partial pressure results in an increase in the amount of hydrides at such free sites. The effect of oxygen on the hydrogen sorption kinetics by the Zr2Fe alloy consists in a decrease in the hydrogen-adsorption efficiency, due to the formation of oxides on the getter surface. [ABSTRACT FROM AUTHOR]

The reactions of potassium dibromodicyanoaurate with (3-bromopropyl)triphenylphosphonium and tetraphenylstibonium bromides result in new ionic gold complexes [Ph3P(CH2)2CH2Br][Au(CN)2Br2] and [Ph4Sb·(DMSO-O)][Au(CN)2Br2]. A new ylide complex Ph3PC(H)(COOMe)Au(CN)2Cl was synthesized in acetonitrile from potassium dichlorodicyanoaurate and triphenylphosphonium(methoxycarbonyl)methanide. The structure of the obtained compounds was studied by the X-ray diffraction analysis method. [ABSTRACT FROM AUTHOR]

Metallurgy is one of the key industries both in Russia and in the world. It has a significant influence on the situation in related industries. Therefore, the current state analysis of ferrous metallurgy production and its formation based on the short-term technological forecast is essential. Based on the foregoing, the research was aimed at analyzing the current state of ferrous metallurgy production in Russia and the impact of the COVID-19 pandemic on the prospects for industry development in the short term. The research studies the state of the ferrous metallurgy production in Russia and abroad before the COVID-19 pandemic, as well as the volume of industrial production in ferrous metallurgy and the industry structure. The COVID-19 pandemic has triggered a serious global recession, necessitating an analysis of the forecast for the development of the ferrous metallurgy industry. The research concludes that the Russian ferrous metals market is so far affected to a lesser extent compared to the European one. [ABSTRACT FROM AUTHOR]