Emission spectra from an atmospheric-pressure dielectric barrier discharge (DBD) with HgBr2/He or HgBr2/Xe/Kr mixtures, as well as the electrical characteristics, were investigated at repetition frequencies of sinusoidal voltage pulses up to 125 kHz. In the spectra, the study revealed radiation from HgBr(B–X, C–X) exciplex molecules, atomic lines of mercury and rare gases, and in mixtures with xenon, radiation of XeBr(B–X, B–A) exciplex molecules. Regularities in the spectral characteristics of the radiation from the gas-discharge plasma were discussed. The electron energy distribution function, the specific energy lost in the processes involving electrons, the electron temperature and density, and the rate constants of elastic and inelastic electron scattering by the components of the working mixture were calculated as functions of the reduced field E/N. The high-frequency atmospheric-pressure barrier discharge in mixtures of mercury dibromide with gases can be used in multi-wavelength exciplex lamps, operating in the UV and visible regions.

The characteristics of the nanosecond overvoltage discharge ignited between semiconductor electrodes based on the CuInSe2 chalcopyrite compound in the argon and nitrogen atmospheres at gas pressures of 5.3–101 kPa are reported. Due to the electrode sputtering, chalcopyrite vapor enters the discharge plasma, so that some CuInSe2 molecules become destroyed, whereas the others become partially deposited in the form of thin films on solid dielectric substrates located near the plasma electrode system. The main products of the chalcopyrite molecule decomposition in the nanosecond overvoltage discharge are determined; these are atoms and singly charged ions of copper and indium in the excited and ionized states. Spectral lines emitted by copper and indium atoms and ions are proposed, which can be used to control the deposition of thin chalcopyrite films in the real-time mode. By numerically solving the Boltzmann kinetic equation for the electron energy distribution function, the electron temperature and density in the discharge, the specific losses of a discharge power for the main electronic processes, and the rate constants of electronic processes, as well as their dependences on the parameter E/N, are calculated for the plasma of vapor-gas mixtures on the basis of nitrogen and chalcopyrite. Thin chalcopyrite films that effectively absorb light in a wide spectral interval (200–800 nm) are synthesized on quartz substrates, by using the gas-discharge method, which opens new prospects for their application in photovoltaic devices.

No abstract

No abstract

The results of studying the conditions of synthesis and luminescence of aluminum oxide nanoparticles in a plasma of an overstressed nanosecond discharge ignited between aluminum electrodes at an interelectrode distance of 2 mm and air pressure in the range of 50-202 kPa are presented. It was shown that the plasma of the investigated discharge is characterized by a wide luminescence band in the spectral range of 300–430 nm, which is associated with the formation of F and F + centers. The research results can be used in micro-nanotechnology, biomedical engineering to obtain nanostructured alumina substrates, on which other nanodevices and films from biomaterials can be placed. The aim of the work was to establish the possibility of detecting small nanoparticles - aluminum oxide nuclei by emission spectroscopy methods and the synthesis of nanostructured alumina films under atmospheric conditions (without the use of vacuum technology) over a large area.

Curcumin The design of the device for producing a high-current, bipolar nanosecond discharge over the surface of a non-metallic liquid (water, electrolytes, alcohols, etc.) in air is given. Air pressure is ranged from 5 to 101 kPa. The distance between the tip of the blade and the surface of water or liquid (5% solution of copper sulfate in distilled water) was 4 mm, and the distance between parallel metal blades was 40 mm. The conditions for uniform plasma overlapping of the electrolyte surface between the metal blades are established. The spatial, electrical, and optical characteristics of the discharge are investigated. It is shown that the discharge under study allows obtaining colloidal solutions of copper nanoparticles in distilled water in a macroscopic amount (1 liter or more). The developed reactor is of interest for use in poisonous chemical solution disinfection systems, solutions based on dangerous bacteria and viruses for which the use of traditional systems with a point spark discharge or a barrier discharge becomes ineffective. The rector is also promising for the synthesis of colloidal solutions of transition metal oxide nanoparticles from solutions of the corresponding salts. These solutions can be used in micro-nanotechnology and for antibacterial treatment of plants in greenhouses, processing of medical instruments and materials.

No abstract

Parameters of the nanosecond overvoltage discharge plasma in an air gap of (1÷5) × 10 −3 m between the electrodes, which contains the vapor of an electrode material (Zn, Cu, Fe) injected into plasma due to the ectonic mechanism, have been studied. The dependences of those parameters on the ratio / between the electric field strength and the particle concentration in the discharge are calculated for the "air-copper vapor" system, by using the numerical simulation method. K e y w o r d s: nanosecond discharge, air, radiation emission by atoms and ions, plasma parameters, zinc, copper, iron.