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Information × Registration Number 0223U001553, 0122U001662 , R & D reports Title Complex studies of formation processes and properties of nano- and microparticles in plasma of gas discharges of different types popup.stage_title Head Azarienkov Mykola O., Доктор фізико-математичних наук Registration Date 31-01-2023 Organization V.N. Karazin Kharkiv National University popup.description2  Experiments were conducted on the formation and retention of nanoparticles (NPs) in the plasma of a radio-frequency capacitive discharge in acetylene with vertically positioned internal electrodes. Using SEM and TEM methods, it was shown that the NPs found on the horizontal wall of the tube after the discharge burn are spherical in shape with a predominant diameter of approximately 400 nm - 600 nm. HRTEM analysis shows their amorphous structure. At the same time, no such NPs were detected on the vertical electrodes, only a polymer film was deposited. In order to find out the possibility of the exit of NPs from the plasma in the direction of the vertical electrodes, a model of the retention of NPs in the near-electrode shell of the RF capacitive discharge was developed. The results of the calculations agree with our experimental data. A physical and numerical model was also developed to describe the charge distribution function of nano- and submicron-sized particles and other parameters in the argon-dusted afterglow plasma. Results of numerical calculations compared with experimental data of scientists of the University of Orleans. They are in good agreement, if the dusty discharge model takes into account the emission of electrons from the surface of the dust particles during collisions with this surface of excited argon atoms. The study was carried out taking into account the transition from ambipolar to free diffusion, stepwise ionization and excitation of argon atoms in the afterglow plasma. Traps and extraction windows for negatively charged nanoparticles are also considered in cylindrical geometry, which occupy a small part of the cross-section of the plasma flow in the induction discharge, but capture most of the nanoparticles at different geometries of the discharge and the transport channel. Product Description popup.authors Denysenko Ihor B. Dudin Stanislav V. Lisovskiy Valeriy O. Maslov Vasyl I. popup.nrat_date 2023-01-31 Close