Mixed transition metal sulfides are promising materials for positive electrodes of asymmetric supercapacitors because they have a large potential for increasing the electrical characteristics of these devices. The paper presents the results of a study of a material based on spinel CuCoNiS_xO_4−x with both sulfide and oxide sublattices, prepared by a one-step hydrothermal method directly on nickel foam, forming an array of whiskers. Electrochemical studies showed that a positive electrode, CuCoNiS₂O₂, exhibited a high specific capacitance of 3612 F g⁻¹ at a current density of 1 A g⁻¹. The assembled asymmetric supercapacitor with activated carbon as a negative electrode achieved a specific capacitance of 133.5 F g⁻¹ at 1 A g⁻¹ and a potential window of 1.7 V. Its energy density was 53.6 Wh kg⁻¹ at a power density of 805 W kg⁻¹ and the power density reached 17,000 W kg⁻¹ at an energy density of 18.9 W h kg⁻¹. The assembled device exhibits 52% of capacitance retention after the 20,000 cycles at a current density of 10 A g⁻¹ with 97% coulombic efficiency. These results demonstrate that the CuCoNiS_xO_4−x system is competitive with other quaternary transition metal sulfides, and this type of spinel is a perspective electrode material for high-performance supercapacitors.

For the first time porous tungsten coatings were obtained by vacuum annealing of coatings consisting of both lead solution in β-W and a mixture of Pb solution in β-W and pure lead. Electron-microscopic studies of the obtained coatings before and after vacuum annealing at 800 оС for 1 hour and 6 hours were carried out. The formation of a new phase of tungsten with an octa-lattice and parameter a = 0.4878±0.0005 nm was recorded.

This study aimed to develop a technology for synthesizing non-degrading porous coatings that remain stable under the conditions of outer space. Using the magnetron sputtering method, we obtained vanadium–lead system coatings over a wide range of mutual concentrations from 6 to 44.9 at. % Pb. X-ray and electron microscopic studies were conducted on the obtained coatings. As a result of the research, a dependence of the film structure on changes in the lead concentration in vanadium was demonstrated. A correlation between the lead concentration in vanadium, the size of the resulting crystallites of solid solutions, and the change in the lattice parameter of the solid solution depending on the lead concentration in the coating was identified. A new possibility of producing porous vanadium coatings through vacuum annealing of the obtained alloy-based coatings in the V-Pb system was shown.

The pressing issue of global warming, coupled with the increasing depletion of fossil fuels, highlights the necessity for sustainable energy solutions. In this context, hydrogen stands out as a viable option, possessing the capacity to revolutionize critical industries, including fuel cells, internal combustion engines, and gas turbines. An effective approach to enhancing numerous chemical and technological processes in liquid and steam–gas mixtures is the establishment of cavitation mixing zones for the reacting components. These zones are produced in specialized reactors that operate on the principles of hydrodynamic effects applied to the reaction medium. The study focused on the design of the cavitation-jet chamber utilizing the k–$\omega$ Turbulence Model and Particle Tracing Model. As a result, the influence of the inlet velocity on cavitation formation and the uniformity of mixing was investigated. Ripley’s K-function was used to analyze the results of particle distribution. The influence of the screw on flow turbulence and the uniformity of particles was evaluated. Analysis through the K-function indicated a decrease in uniformity at lower velocities, with noticeable turbulization of the flow occurring at high velocities, which facilitated better mixing. In contrast, without the screw, the flow exhibited a high longitudinal velocity and minimal transverse velocity, limiting particle dispersion to the radius of the nozzle and resulting in inefficient mixing. It was found that the inclusion of the screw not only enhanced particle distribution but also maintained the size of the cavitation zones, thereby improving the overall efficiency of the design.

For the first time, porous tungsten coatings were obtained by vacuum annealing of coatings consisting of both lead solution in β-W and a mixture of Pb solution in β-W and pure lead. Electron microscopic studies of the obtained coatings before and after vacuum annealing at 800 °C for 1 h and 6 h were carried out. The formation of a new phase of tungsten with an octa-lattice and parameter a = 0.4878 ± 0.0005 nm was recorded.