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Документ The classes of inorganic substances(2020) Ved, M. V.; Korohodska, A. M.; Proskurina, V. O.The classes of inorganic substances are the fundamental material in the course of general and inorganic chemistry studying. The classification of substances facilitates the study and systematizes the whole variety of inorganic compounds in nature. Knowing the structural features of the chemical compounds classes, it is possible to characterize the properties of their individual representatives. The purpose of the work is to help students fill the missing knowledge and fully master the presented material. The nomenclature, production and chemical properties of the main classes of inorganic compounds (oxides, bases, acids and salts) are considered.Документ Cobalt based coatings as catalysts for methanol oxidation(Науково-технологічний комплекс "Інститут монокристалів", 2020) Nenastina, T. A.; Ved, M. V.; Sakhnenko, N. D.; Yermolenko, I. Yu.; Volobuyev, M.; Proskurina, V. O.The cobalt based coatings with refractory metals (Mo, W, Zr) were deposited from pyrophosphate-citrate electrolytes in a pulsed mode. It has been shown that, with increasing current density, Co-Mo-W and Co-W-ZrO2 alloys are enriched in tungsten, grain sizes decrease, but a network of cracks appears on the surface of the Co-Mo-W coating. In the Co-Mo-ZrO2 coating, with increasing current density, the zirconium content increases due to molybdenum, and the surface is the most fractured and small-globular. The surface roughness parameters for Co-Mo-ZrO2 are one order of magnitude higher than those for Co-Mo-W. Cyclic voltammograms show that the Co-Mo-ZrO2 deposits are characterized by the highest stability under anodic polarization due to the inclusion of molybdenum and zirconium(IV) oxide in their composition. The kinetics of the methanol anodic oxidation on electrodes coated with cobalt alloys was studied, and the participation of intermediate metal oxides in oxygen transport was revealed. A significant increase in the anode current peak indicates a higher electro-catalytic activity of the zirconium-containing coatings among the studied alloys.Документ Functional ternary Fe-Co-Mo(W) coatings(Kyiv National University of Technologies and Design, 2017) Yermolenko, I. Yu.; Ved, M. V.; Sakhnenko, N. D.; Sachanova, Yu. I.; Lagdan, I. V.; Proskurina, V. O.The researchers and technologists increased interest to multicomponent galvanic alloys of iron triad metals with refractory elements (W, Mo etc.) [1, 2] is caused by several reasons. The main is creation new technology of coatings with a unique set of functional properties such as wear and corrosion resistance, increased catalytic activity and microhardness, magnetic properties, and others [3, 4]. This allows replacing toxic chromium-plating, to create effective catalytic materials, more available compared to traditional platinum based systems [5] and to obtain new soft magnetic films for the production of magnetic head elements for recording and reproducing information [6]. In this connection, the electrochemical methods of deposition are considered to be a competitive alternative to the physical methods of production [7] due to the possibility of flexible process control and monitoring. This enables the formation of coatings of a varying composition and structure, which is a key factor for production of the materials with specified functional properties. Many scientific papers delve into the electrodeposition of binary [8, 9] and ternary [10] iron and cobalt alloys with refractory components. In [11], Fe-W and Fe-W-P coatings with high wear resistance and corrosion resistance were obtained from electrolytes of different composition. It is noted that friction coefficient of amorphous ternary Fe-W-P alloys is lower than that of binary Fe-W coatings. The authors of [12] emphasize the increased wear resistance of Fe-W, Ni-W and Co-W coatings obtained from citrate and citrate-ammonia electrolytes at low bulk current densities. The molybdenum incorporation into cobalt deposits leads to a significant decrease in the coercive force and an increase in the saturation magnetization of the materials [13]. It is shown [14] that the molybdenum content in the alloy increases as the potential shifts toward negative values. The structure of deposits varies from close-packed hexagonal to mixed crystalline and amorphous with increasing current density. depends on coatings thickness: thin films have an amorphous structure. The great practical interest for works [15, 16] are due to electrosynthesis of ternary Fe-Mo-W alloys with increased physic-mechanical and corrosion protective properties for hardening machine parts. Obviously, in each individual case the formation of the coating depends on the qualitative and quantitative composition of the electrolyte and on the synthesis conditions. It should be noted the modes and parameters of the electrolysis predetermine in a particular way the concentration ratio of the alloy components and phase composition of the coatings [17]. Accordingly, the functional properties of coatings depended on the composition and structure can be controlled by deposition conditions. It should be noted that most published results covers to binary alloys Fe (Ni, Co) -Mo (W). Thereby it is relevant to study the process of electrosynthesis of ternary alloys and to analyze their properties.Документ Galvanochemical formation of functional coatings by the cobalt-tungsten-zirconium alloys(Institute for Single Crystals, 2020) Nenastina, T. A.; Ved, M. V.; Sakhnenko, N. D.; Proskurina, V. O.; Fomina, L. P.The functional properties of ternary Co-W-Zr(ZrO₂) alloys obtained in a pulsed mode from pyrophosphate-citrate electrolytes are discussed. The obtained coatings are characterized by a uniformly developed surface without cracks and a sufficiently high and reproducible microhardness. It was determined that the size of the globules on the alloy surface decreases with increasing of the current density to 10 A/dm². It was found that increase of temperature favorably affects the current efficiency of the alloy and the microhardness of the Co-W-Zr(ZrO₂) coating. The modes of electrosynthesis of the coatings by cobalt-tungsten-zirconium alloys are substantiated, an their influence on the functional properties of the alloy and current efficiency is investigated.Документ Internal stresses and magnetic properties of Fe-Co electrolytic coatings(Науково-технологічний комплекс "Інститут монокристалів", 2017) Proskurina, V. O.; Yermolenko, I. Yu.; Zyubanova, S. I.; Shipkova, I. G.; Avramenko, B. A.; Sachanova, Yu. I.Consideration was given to the effect of electrolysis parameters on the composition and the properties of electrolytic iron-cobalt film coatings obtained from citrate electrolytes. The interconnection between the film composition and the film thickness with its internal stresses and magnetic properties has been studied. It was established that Fe60Co40 alloys show the lowest level of internal stresses for the saturation induction of 1.8 to 2.1 Tl.Документ Research into composition and properties of the Ni–Fe electrolytic alloy(Технологический центр, 2017) Sknar, Y.; Sknar, I.; Cheremysinova, A.; Yermolenko, I. Yu.; Karakurkchi, A.; Mizin, V.; Proskurina, V. O.; Sachanova, Y.Встановлено вплив умов елек-тролізу на склад сплаву Ni–Fe, електроосадженого із метилсульфонатного електроліту. Показано, що натрій сахаринат істотно не впливає на склад сплаву при густині струму вище 2 А/дм². Встановлено, що натрій сахаринат сприяє підвищенню мікротвердості і зниженню внутрішніх напружень і коерцитивної сили покриттів. Проаналізовано залежність досліджених властивостей сплаву Ni–Fe від структури осаду.Документ Research into influence of the electrolysis modes on the composition of galvanic Fe-Co-Mo coatings(Технологический центр, 2017) Yermolenko, I. Yu.; Ved, M.; Karakurkchi, A.; Proskurina, V. O.; Sknar, I.; Kozlov, Ya.; Sverdlikovska, O.; Sigunov, O.Досліджено вплив енергетичних (густина струму і) і часових (тривалість імпульсу tі і паузи tn, співвідношення tі/tn) параметрів електролізу на склад та морфологію покриттів Fe-Co-Mo. Встановлено, що підвищення тривалості імпульсу сприяє збагаченню сплаву молібденом тим більше, чим вище густина струму. Показано, що зі збільшенням густини струму структура поверхні покриттів змінюється від дрібнозернистої до глобулярної.