Перегляд за Автор "Ryshchenko, I. M."
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Документ Electrochemical synthesis of peroxyacetic acid on Pt/PtO and PbO₂ anodes(Lviv Polytechnic National University Institutional, 2020) Bilous, T. A.; Tulskaya, A. G.; Ryshchenko, I. M.; Chahine, I.; Bairachnyi, V. B.The kinetics of anodic processes on Pt/PtO and PbO₂ anodes has been studied in water solutions of acetic acid. The addition of sulfuric acid has a catalytic effect in the electrochemical synthesis of peroxyacetic acid. The choice of promoters of peroxide-particles formation has been proved. I–, Cl– (current efficiency is 1.2–1.5 %) particles have been defined as the most effective for platinum anode and I–, F– (current efficiency is 0.50–0.55 %) have been defined as the most effective for lead-dioxide anode.Документ Formation of nanostructures on the basis of porous anodic niobium oxide(Scientific and Technological Corporation "Institute for Single Crystals", 2019) Ryshchenko, I. M.; Lyashok, I. V.; Gomozov, V. P.; Vodolazhchenko, S. A.; Deribo, S. G.Self-organization of nanoscale structures under an electrochemical treatment is most pronounced during the formation of porous anodic metal (aluminum, titanium, niobium, and tantalum) oxides. A theoretical approach is proposed to describe the processes of the self-organization that allows one to determine the conditions for the formation of porous niobium oxides with amorphous or crystalline structure. The studies have shown the influence of the electrolyte nature on the formation of oxide layers. The use of an activator (fluoride) provides the conditions for the formation of oxides with different surface morphology at the initial stage of anodizing. By varying the mode of niobium anodizing, one can investigate the nature of pore nucleation at the initial stage of their growth, as well as track the in-time evolution of their geometrical dimensions, depending on the formation conditions, and synthesize porous AOFs on niobium with an amorphous or crystalline structure.Документ The Influence of Layer Thickness and Deposition Conditions on Structural State of NbN/Cu Multilayer Coatings(Sumy State University, 2019) Sobol, O. V.; Andreev, A. A.; Meylekhov, A. A.; Postelnyk, A. A.; Stolbovoy, V. A.; Ryshchenko, I. M.; Sagaidashnikov, Yu. Ye.; Kraievska, Zh. V.The influence of the main physical and technological factors of structural engineering (layer thickness, nitrogen atmosphere pressure and bias potential) on the structural-phase state of the NbN/Cu coatings was studied. It was established that with an increase in the thickness of niobium nitride layers from 8 to 40 nm (in the NbN/Cu multilayer composition), the phase composition changes from the metastable NbN (cubic crystal lattice, NaCl structural type) to the equilibrium ε-NbN phase with a hexagonal crystal lattice. At low pressure PN = 7·10 – 4 Torr in thin layers (about 8 nm thick), regardless of the Ub, the NbN phase is formed. The reason for the stabilization of this phase can be the uniformity of the metallic fcc crystal lattice of the δ-NbN phase with the Cu crystal lattice. As the pressure increases from РN = 7·10 – 4 Torr to 3·10 – 3 Torr, a more equilibrium ε-NbN phase with a hexagonal crystal lattice is formed. An increase in the bias potential during deposition from – 50 V to – 200 V mainly affects the change in the preferred orientation of crystallite growth. In thin layers of the NbN phase (about 8 nm), a crystallite texture with the [100] axis is formed. In layers with a thickness of 40-120 nm, crystallites of the NbN phase are predominantly formed with a hexagonal (004) plane parallel to the growth plane. At the greatest layer thickness (more than 250 nm), the NbN phase crystallites are predominantly formed with a (110) hexagonal lattice plane parallel to the growth plane. The results obtained show great potential for structural engineering in niobium nitride when it is used as a constituent layer of the NbN/Cu multilayer periodic system.Документ Purification of Cr(VI)-containing wastewater by chemical precipitation: test results of an experimental-industrial installation(Український державний хіміко-технологічний університет, 2021) Suvorin, A. V.; Shorokhov, M. N.; Ozheredova, M. A.; Bliznjuk, O. N.; Ryshchenko, I. M.; Masalitina, N. Yu.We present the main results of experimental and industrial study of the developed process and pilot plant for purification of the Cr(VI)-containing rinse water by chemical precipitation. This technique implies full or partial return of treated water to rinse workpieces after chromium plating and prepare working solutions (precipitators). We characterize the manufacturing scheme of the pilot plant and the mode of its performance. Saturated aqueous solutions of Cа(OH)₂ and Bа(OH)₂ were used as precipitating reagents. The tests confirmed the possibility of automatic dosing the reagents with due regard for the pH value of a medium, which can be used in both continuous and periodic rinsing. The operating conditions of rinsing the workpieces after electrochemical chromium plating were justified. We derived the equation for the calculation of the total salt content in the rinse water after its purification. We determined the duration of the rinsing without the need to renew the bath volume. The performed calculations substantiated the possibility of reducing the consumption of fresh water supplied for rinsing by the recycling of wastewater without deteriorating the quality of the rinsed workpieces. The reduction of water consumption by 35% was observed as compared with that stated by the regulations.Документ A study of cell membranes in nasal epithelial cells from patients with chronic rhinosinusitis with nasal polyps by means of a fluorescent probe(2019) Onishchenko, A. I.; Tkachenko, A. S.; Nakonechna, O. A.; Korniyenko, Y. M.; Ryshchenko, I. M.; Tsygankov, A. V.; Posokhov, Ye. O.Aim. To assess the state of membranes in nasal epithelial cells obtained from the patients with chronic rhinosinusitis with nasal polyps (CRSwNP) with the help of the fluorescent probe 2-(2ʹ-ОН-phenyl)-5-phenyl-1,3-oxazole. Methods. The state of membrane phospholipid bilayer in suspensions of nasal epithelial cells isolated from ten patients with CRSwNP was evaluated using the fluorescent probe 2-(2ʹ-ОН-phenyl)-5-phenyl-1,3-oxazole that reacts on the physico-chemical properties of its microenvironment. Changes in fluorescence spectra were determined using a Thermo Scientific Lumina fluorescence spectrometer (Thermo Fisher Scientific) 1 hour after the addition of the probe to nasal epithelial cell suspensions. Results. CRSwNP was found to be associated with a higher rate of nasal epithelial cell membrane hydration in the region of phospholipid glycerol moiety, carbonyl groups and aliphatic chains of fatty acids attached to the carbonyl groups. Conclusion. Our findings suggest that CRSwNP is accompanied by the elevated hydration rate of the most polar region, namely polar heads of phospholipids of nasal epithelial cell membranes.