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Information × Registration Number 0307U001711, 0106U001575 , R & D reports Title Interaction of electromagnetic waves and particles fluxes with materials in plasma installations popup.stage_title Спектри перехідного випромінювання та розсіяння в пиловій плазмі пасток КТС. Комплексні дослідження впливу електромагнітного випромінювання різної енергії на властивості оксидних матеріалів. Head Girka Igor Olexandrovich, Registration Date 22-12-2008 Organization Kharkov national university named after V.N. Karazin popup.description2 Object of investigation: Transient induced radiation and transient dissipation in dusty plasma, dimension of strange attractors and radiation effects in crystals and ceramics of magnesium aluminate spinel at irradiation in plasma devices. Aim of investigation: Elaboration of the numerical algorithms of calculating the spectra of transient radiation and dissipations in dusty plasma with taking into account the macro-particles of different geometry. Elaboration of the numerical algorithms of calculating the fractal dimension of strange attractors. Determination of the parameters of luminescence in crystals, transparent ceramics such as spectra, growth and decay, also temperature dependence of luminescence intensity on the types of samples. Method of investigations: Studying the spectra of transient induced radiation and transient dissipation in dusty plasma was carried out using the numerical methods of calculation of induced density of surface charges and currents on charged frames with composite geometry which were specially designed. Fractal dimension of strange attractors was calculated numerically on the base of Tackense theorem for temporary implementations. By using methods of optical spectroscopy the processes of radio-luminescence (RL) were investigated, growth and decay of different luminescence bands, their dependences on the temperature of samples, also complex investigations of thermo-luminescence (TL) processes after X-ray irradiation were provided. Interest to the problem of interaction of potent powerful flows with a wall of fusion reactors, i.e. to "the problem of the first wall" has essentially increased recently. During this interaction, the plasma-dust layer is created near the wall. The wall can evaporate and inject dusty particles into the plasma. The value of the flow of dusty particles from the wall, apparently, depends on many factors. This formation, the dusty plasma, results in originating new interesting physical phenomena, including phenomena of transient induced radiation and dissipation. It is rather probably, that the formation of such plasma-dust layer on the plasma edge can appear to be essential for the plasma confinement as a whole for long duration and large flows in the future thermonuclear devices. Studying the basic properties of dusty plasma becomes an actual problem also because the charged macro-particles can stimulate originating of turbulent modes in it. The RL and TL in spinel crystals and ceramics were investigated to elucidate the radiation induced electronic processes in single crystals grown by Verneuil and Czochralski methods, transparent and translucent ceramics. Both RL and TL spectra demonstrate the UV-band related to electron-hole recombination luminescence at intrinsic defects, green, and red luminescence identified with emission of Mn2+ and Cr3+ ions, respectively. Kinetics of growth of different RL luminescence bands in dependence on the dose at the prolonged X-irradiation show the competitive character of charge and energy transfer between defects and impurity ions. The dependence of RL intensity on the temperature of sample was measured in the range of 300-750 K and compared with TL for different emission bands. The results of this activity can be used for the solution of problems of the thermonuclear devices with magnetic confinement, in which the dusty plasma is found. With the help of the artificial introduction of dusty particles of the given geometry and structure to the plasma-dust layer one can purposefully control the processes, which take place in the thermonuclear devices. The obtained parameters of luminescence in crystals and ceramics will be used for prediction of changes in properties of materials at the influence of plasma factors. Product Description popup.authors popup.nrat_date 2020-04-02 Close