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Документ80 років кафедрі технічної електрохімії(НТУ "ХПІ", 2010) Байрачний, Борис ІвановичРозглянуто підсумки діяльності викладачів і наукових співробітників кафедри технічної електрохімії за 80-річний період діяльності. Особливу увагу приділено роботам, що проводяться кафедрою за останні 15-20 років. Освітлена активна діяльність викладачів, аспірантів і студентів кафедри в удосконаленні навчального процесу, творчих зв'язків з виробництвом та науковими установами. ДокументAnodic dissolution of stainless steel in acid solutions(Таврійський національний університет ім. В. І. Вернадського, 2019) Shtefan, V. V.; Kanunnikova, Nadiia; Leshchenko, S. A.; Balamut, NataliiaIn this work, the kinetics of anodic dissolution of stainless steel was studied using linear voltammetry. It is shown that an increase in the concentration of molybdates leads to an increase in anodic currents and an expansion in the region of active dissolution, which indicates that the oxoanions of the steel surface are passivated. The influence of electrolyte composition on the formation of a passive film was investigated. It has been established that at high potential sweep rates, dense layers of stoichiometric oxide do not have time to form and the passive film has a defective structure. Molybdenum-, zirconium-, aluminum-, titanium-containing compounds have been shown to increase the passivity area, which is the basis for the formation of protective oxide films on stainless steel. ДокументCarbon Steel (St.3) Corrosion Caused by the Circulating Water Flow(Kyiv National University of Technologies and Design, 2018) Pilipenko, A. I.; Pancheva, H.; Khrystych, E. V.; Smirnova, O. L. ДокументChemical deposition of CdS films from ammoniac-thiourea solutions(Технологический центр, 2018) Pancheva, Hanna; Khrystych, Olena; Mykhailova, Evgeniia; Ivashchenko, Maryna; Pilipenko, AlexeiThis paper investigates the process of chemical deposition of CdS films from ammonia-thiourea solutions. It was established that a change in the turbidity of solution occurs in the process of chemical deposition. The results of visual observations and measurement of turbidity of solution allowed us to establish that these dependences could be used to monitor the status of the process. Visual observations correlate with the obtained dependences for turbidity and suggest that the chemical deposition of CdS includes the accumulation of colloidal-dispersed precipitate in the volume of solution, agglomeration of CdS particles, and a stationary mode of the CdS film growth at the surface of a sample. The first stage of the process is matched by a sharp increase in the turbidity of solution; the second stage is accompanied by the emergence of a maximum in the dependence. No significant change in turbidity occurs at the third stage. The observation of morphology of the resulting precipitate allowed us to establish working concentrations of reagents in solution, which ensure obtaining a high-quality CdS film with a thickness not less than 100 μm. The working concentrations of cadmium chloride, ammonia, and thiourea are, respectively, 1.8, 0.6, and 8.4 g·l⁻¹. It was assumed that the CdS formation is accompanied by the formation of thiourea. This is confirmed by data on the analysis of a working solution. An analysis of the solution revealed high concentrations of the CO₃²⁻ ions, which are a product of the thiourea decomposition. The data obtained are a preliminary stage in the development of a technology of chemical deposition of CdS films from ammonia-thiourea solutions. ДокументThe choice of anode material for the electrochemical synthesis of peroxyacetic acid(Kyiv National University of Technologies and Design, 2017) Bilous, T. A.; Tulskaya, A. G.; Matrunchyk, O. L.A high-purity peroxyacetic acid may be produced electrochemically. The kinetics of anodic processes at electrolysis of acetic acid water solutions have been studied with application of different kinds of anodic materials. It has been shown that the formation of peroxyacetic acid is possible when the anodic potential is above 2,0 V. The choice of lead dioxide plated on titanium current-lead was justified. Application of lead dioxide in the electrochemical synthesis of peroxyacetic acid allows to increase the current output up by 8-12 % comparing to platinum. ДокументCombined Cathode Processes in the Electrochemical Synthesis of Sodium Hypochlorite(Київський національний університет технологій та дизайну, 2019) Rutkovska, K. S.; Tulskyi, G. G.; Chahine, I. H.; Tulska, A. G. ДокументCorrosion resistance of AISI 304 steel from compositional oxide coatings(Фізико-механічний інститут ім. Г. В. Карпенка Національної академії наук України, 2020) Shtefan, V. V.; Kanunnikova, Nadiia; Smyrnov, A.; Shepil, T. ДокументDesign of the modified oxide-nickel electrode with improved electrical characteristics(Технологический центр, 2017) Sincheskul, Alexander; Pancheva, Hanna; Loboichenko, Valentyna; Avina, Svetlana; Khrystych, Olena; Pilipenko, AlexeiThe influence of lithium hydroxide was examined on the characteristic features of charge and discharge and electrical parameters of the sintered oxide-nickel electrode in a solution of potassium hydroxide. It is shown that the introduction of LiON to the composition of electrolyte does not lead to a change in the specificity of charge and discharge processes of the electrode. The experimental work conducted allowed us to establish dependences that connect the magnitude of analytical concentration of the Li⁺ ions to specific capacity and capacity output of the electrode. The results obtained show that an increase in the content of Li⁺ ions in the electrolyte from 1 to 100 g·l⁻¹ causes a growth of the electrode’s specific capacity from 0.79 (А·h)·cm⁻² to 1.84 (А·h)·cm⁻². It is optimal to introduce LiOH to the electrolyte in the amount of 30‒50 g·l⁻¹. It was established that the magnitude of specific capacity of the oxide-nickel electrode depends on the number of charge-discharge cycles and increases with an increase in the number, which is related to the slow character of the course of mass transfer processes in the volume of active mass of the electrode. ДокументThe Differential Voltametry Method for Studying the Combined Cathodic Processes in Aqueous NaCl Solution(Київський національний університет технологій та дизайну, 2020) Rutkovska, K. S.; Tulsky, G. G.; Tulska, A. G.; Homozov, V. P. ДокументElectrochemical Dissolution of Pseudo Alloys of Tungsten Carbide Type in Acid Electrolytes(Київський національний університет технологій та дизайну, 2019) Osмanоvа, M.; Lyashok, L.; Leshchenko, S.; Isмаhilоvа, E.; Kolupaev, I.The electrochemical behaviour of the WC-Co pseudo alloy in acid solutions of HNO3, H2SO4 and HCl has been studied. For practical use, an aqueous solution of 4 mol·dm-3 H2SO4 has been chosen. To prevent the formation of oxides of tungsten, there has been justified the use of a reducing agent - hexamine additive. A method for processing a pseudo alloy in 4 mol·dm-3 H2SO4 solution containing 0.2 – 0.3 mol·dm-3 reducing agent – hexamine, which allows to obtain a tungsten powder in slime. ДокументElectrochemical Production of Tungsten Powders from Tungsten Hardmetal Waste(Springer Science, 2020) Tulskiy, Gennadiy; Liashok, L. V.; Osmanova, M. P.; Kolupaev, I. N.Hardmetals intended to perform in harsh operating conditions are developed with the use of metallic powders, in particular, tungsten powders. The growing consumption of tungsten in industry necessitates the improvement of techniques employed to produce it from industrial waste. The objective of this research effort was to reduce metallic tungsten (as a powder) from chloride and chloride–fluoride melts and determine the factors influencing its particle size. The starting material was tungsten oxide (WO3) produced electrochemically from processed raw material (VK-6 tungsten carbide pseudoalloy). The melts were KCl–NaCl–CsBr and NaCl–KCl–CsBr–Na3WO3F3 eutectic mixtures. When the melt with a high WO2F42– content was subjected to electrolysis, tungsten precipitated as a superfine powder. The precipitate morphology showed that the tungsten particl esize was dependent on electrolysis conditions. A relatively inexpensive and effective method of producing tungsten powders was developed upon the research. ДокументElectrochemical synthesis of hydrogen with depolarization of the anodic process(2016) Tulskiy, Gennadiy; Tulskaya, A. G.; Skatkov, L. I.; Gomozov, V. P.; Deribo, S. G.A new active composite coating for graphite gas diffusion electrode for hybrid sulfur cycle was proposed. The kinetics of oxidation of SO₂ were studied on porous graphite anodes with different catalytic coatings. It was shown that the most efficient composite coating is based on activated carbon and platinum supported on graphite gas diffusion substrate. The voltage drop in the laboratory electrochemical cell was 1.3 V at a current density of 1000 A·m⁻². This corresponds to a specific consumption of 3.1 kWh electric energy per 1 m³ of hydrogen. ДокументElectrochemical synthesis of peroxyacetic acid on Pt/PtO and PbO₂ anodes(2018) Tulskaya, A. G.; Bilous, T. A. ДокументElectrode processes in electrochromic anodic oxide films on niobium(Khalsa Publications, 2018) Gomozov, V. P.; Tulskiy, Gennadiy; Skatkov, L. I.; Deribo, S. G.; Tulskaya, AlenaWe review the following issues: peculiarities of polycrystalline AOP development at niobium in nitrate salt melt at temperatures of Nb₂O₅ recrystallization, the mechanisms of change in structure and properties of niobium pentoxide in the result of electrode processes under cathodic polarization (at the model structure of polycrystalline film), as well as the methods of amorphous electrochromic AOP development and ways of electrochromic processes optimization at such films. ДокументElectrodeposition of brass from polyligand electrolyte based on pyrophosphate(Фізико-механічний інститут ім. Г. В. Карпенко, 2019) Serhiienko, Olena; Artemenko, Valentina; Rutkovska, Katerina; Maizelis, AntoninaThe purpose of the research is to determine the conditions for brass electrodeposition from a polyligand electrolyte containing pyrophosphate and citrate metal complexes. Methods of cyclic voltammetry and galvanostatic deposition were used. It is determined the region of current densities, in which the current efficiency is the highest, the deposit is more uniform in the thickness, and alloy composition is practically unchanged. ДокументElectrodeposition of bronze coatings from pyrophosphate-trilonate electrolyte(National Technical University "Kharkiv Polytechnic Institute", 2017) Maizelis, A. V.; Ovcharenko, G. V. ДокументElectrodeposition of Cu-Zn alloys from pyrophosphate-citrate electrolyte(Osnovy, Polska, 2019) Serhiienko, O. Z.; Artemenko, V. M.; Maizelis, A. O.The modern industry requires functional coatings of copper-zinc alloys that are traditionally deposited from toxic cyanide electrolytes. The purpose of the research is to determine the conditions for copper and zinc codeposition from a polyligand electrolyte containing pyrophosphate and citrate metal complexes. Methods of chronopotentiometry, chronoamperometry were used. It is determined the region of current densities, in which the current efficiency is the highest, and alloy composition is practically unchanged. The results can be used to develop the manufacturing method without the use of cyanide compounds. ДокументElectrodeposition of iron-molybdenum coatings from citrate electrolyte(Pleiades Publishing, 2014) Ved, M. V.; Sakhnenko, N. D.; Karakurkchi, A. V.; Zyubanova, S. I.Specifi c features of the electrodeposition of iron–molybdenum coatings from a citrate electrolyte based on iron(III) sulfate and sodium molybdate in dc and unipolar pulsed modes were studied. It was demonstrated that bright compact coatings with varied content of molybdenum can be produced by varying the relative concentrations of salts of the alloy-forming components and the solution pH. The current density ranges providing the high efficiency of the galvanostastic electrolysis were determined and it was shown that using the pulsed mode makes smaller the amount of nonmetallic impurities in a coating, diminishes its roughness and leads to formation of surface layers with a more uniform composition, The iron–molybdenum coatings exhibit a high corrosion resistance in corrosive media and physicomechanical properties improved as compared with the base metal, which makes it possible to recommend these coatings for protection from corrosive-mechanical disintegration and restoration of the surface of worn articles. ДокументElectrodeposition of very hard coatings of cobalt–molybdenum alloy(Фізико-механічний інститут ім. Г. В. Карпенка НАН України, 2017) Shtefan, V. V.; Yepifanova, A. S.; Kovaliov, A. A.; Bairachnyi, B. І.The process of electrodeposition of Co–Mo alloy with ammonium trilonate electrolyte was investigated. The influence of electrolyte pH and the current density on the current efficiency and molybdenum content of the alloy was shown, the structure and microhardness of coatings was studied. As a result of the electrolysis modes with the coating containing molybdenum to 85% and hardness to 429 kg/mm2 are proposed.