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Information × Registration Number 0226U002861, (0124U000972) , R & D reports Title Formation of negative ions and their fluxes in a chemically active plasma popup.stage_title Дослідження утворення негативних іонів та їхніх потоків в хімічно активній плазмі і розробка моделей для опису цих процесів Head Sereda Ihor M., Кандидат фізико-математичних наук Registration Date 09-03-2026 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 The physical processes in electronegative gas discharges and in plasmas containing negative ions and nanoparticles were investigated. Using a movable anode, the voltage drop across the cathode sheath of a DC discharge and the anode voltage drop in various gases were determined, and the reduced electric field E/p in the positive column was measured. It was shown that in electronegative gases the E/p values significantly exceed those in argon and nitrogen due to electron losses caused by attachment. For oxygen discharges, the existence of H- and T-modes with different electric field and current characteristics was established. In the T-mode, the formation and propagation of double layers with a phase velocity of about 5 km/s were observed; the oscillation frequency was found to be inversely proportional to the length of the positive column. Optical spectroscopy revealed the dominance of molecular and atomic oxygen emission and clarified the mechanisms of O2⁻ and O⁻ ion formation. A Penning discharge with Zr50V50 metal-hydride cathodes operated at low pressure and high voltage was implemented, providing a twofold increase in the H⁻ current compared with copper cathodes at the same input power. An electromagnetic filter for negative ion separation was developed and experimentally validated. An increase in the fraction of atomic hydrogen and the efficiency of internal gas feeding due to hydrogen desorption from the metal-hydride cathode were confirmed. Theoretical and numerical models of pulsed Ar/C2H2 plasma with nanoparticles were developed to describe the balance of charged and neutral species and the particle charging process in different discharge phases. The conditions under which negative ions significantly affect nanoparticle charging were identified, and the possibility of charge sign reversal at the late afterglow stage was demonstrated. Product Description popup.authors Hennadii P. Burmaka Igor B. Denysenko Dmitro L. Grekov Ivan I. Okseniuk Valerii О. Lisovskyi Osmaiev Ruslan O. Yarova Lyubov B. Yaroslav O. Hrechko Olena H. Nosova popup.nrat_date 2026-03-09 Close