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Information × Registration Number 0225U002240, (0124U000972) , R & D reports Title Formation of negative ions and their fluxes in a chemically active plasma popup.stage_title Створення та оптимізація експериментального обладнання, числових кодів, проведення верифікаційних досліджень Head Sereda Ihor M., Кандидат фізико-математичних наук Registration Date 25-02-2025 Organization V.N. Karazin Kharkiv National University popup.description1 Development of new physical principles, fundamental principles and specific technological techniques for the formation of negative ion fluxes, as well as finding out of the influence of negative ions on the formation of nanoparticles in stationary and pulsed electronegative plasma. It is planned for this purpose to develop a gas discharge chamber with a moving anode with automation of all measurements; to create a diagnostic complex consisting of a Langmuir probe, a resonance probe, an energy analyzer with magnetic filtering, and an optical emission spectrometer; to investigate spatial profiles of stationary plasma parameters by the moving anode method, as well as probe and emission-spectral methods in various electronegative gases; to investigate the influence of the time characteristics of a pulsed discharge on the generation of fluxes of negative ions; to investigate the conditions for the formation of H– ions and the impact of the metal hydride element on the plasma parameters; to investigate the formation and extraction of negative H– ions from the plasma with metal hydride supply of vibrationally excited hydrogen; to optimize the operation of the metal hydride element and the H– ion extraction system; to develop an analytical 1D model of electronegative plasma for the case of several types of positive and negative ions; to develop analytical and numerical 0D models of pulsed Ar and Ar/C2H2 plasma with nanoparticles, taking into account charge fluctuations of nanoparticles and diffusion of negative ions to the walls of the discharge chamber; to establish how external conditions impacts on the properties of pulsed Ar and Ar/C2H2 gas discharges with nanoparticles, to compare the results of numerical calculations with experimental data and provide recommendations for controlling the formation of negative ions and nanoparticles in a pulsed Ar/C2H2 plasma. popup.description2  A discharge device and a diagnostic complex have been created, based on the idea of increasing the intensity of negative ion generation in the afterglow phase of a pulsed discharge and their localized extraction in time with spatial and temporal control. The effect of ion-stimulated desorption on the longitudinal emission of charged particles from the source has been studied. The dynamics of the energy distribution functions of ions and electrons have been investigated and their dependence on the external parameters of the discharge has been determined. A phenomenological theory of ion-stimulated hydrogen emission under conditions of bombardment of the surface of a metal hydride cathode by plasma ions has been constructed. Analytical and numerical models of pulsed Ar plasma with nanoparticles have been developed, taking into account fluctuations in the charge of nanoparticles associated with its discreteness. The model allows calculating the average charge of nanoparticles, as well as the charge distribution function of nanoparticles under various conditions. The function is obtained from the basic equation for a single-step stochastic process, as well as by describing the charge distribution function of nanoparticles as a Gaussian function. Product Description popup.authors Burmaka Hennadii P. Vinnichenko Vladyslav V. Harkusha Ihor Ye. Hrekov Dmytro L. Denysenko Ihor B. Kanishсheva Mariia M. Lisovskyi Valerii O. Osmaiev Ruslan O. Khludieieva Liudmyla I. popup.nrat_date 2025-02-25 Close