Electrical and optical characteristics of inert-gas plasmas in spatially nonuniform electrode systems

The characteristics of unipolar and bipolar corona discharges in mixtures He/Ar/Kr, He/Ar/Xe, and He/Kr/Xe at atmosphere pressures in electrode systems of the point-plane and point-grid type distributed along the length. It is shown that bipolar corona discharges can be used in the preionization systems of high-pressure inert-gas-atom lasers. The spectral characteristics of the plasma are investigated, and the dependence of the relative intensity of the radiation in the lines Ar(4s-4p), Kr(5s-5p), and Xe(6s-6p) on the composition and pressure of the working mixtures and on the value of the corona discharge current are determined. Zh. Tekh. Fiz. 67, 15–18 (November 1997)     

Optical characteristics of a transverse volume discharge in a helium-hydrogen chloride mixture

The emission characteristics of a transverse volume discharge in a He: HCl = 10: 1 mixture at a total pressure of 1–8 kPa were investigated. The plasma volume was 18 × 2.2 × 1 cm³, the interelectrode distance was d=2.2 cm, and the charging voltage of the main storage capacitor was 5–10 kV. The emission characteristics of the discharge were studied in the spectral range of 500–1000 nm. This type of discharge can be used in pulsed dry-etching plasmochemical reactors. The density of atomic chlorine radicals in the plasma was optimized in terms of the pressure of the initial working He-HCl mixture by measuring the relative radiation intensity of the Cl 837(5)-nm spectral line. The density of molecular radicals can be monitored indirectly by recording radiation from the excited chlorine-free decomposition products of HCl molecules (the H_α 656-nm line).     

Optical characteristics of laser-produced antimony plasma

The processes occurring in expanding laser-produced antimony plasma are investigated by the emission spectroscopy method. The plasma expansion velocity, the recombination time of SbII, and the electron temperature and density are determined from the dynamics of SbI line emission. Based on the results obtained, the processes occurring during the formation and expansion of laser-produced antimony plasma are qualitatively analyzed.     

Characteristics of a nanosecond discharge in atmospheric air with a liquid electrolytic electrode

The spatial, electric, and radiative characteristics of a pulse-periodic nanosecond discharge between an electrode based on a system of blades and the distilled water surface as well as an aqueous solution of zinc sulfate in atmospheric air are considered.     

Synthesis and Investigation of Piezophotocatalytic Properties of Polyvinylidene Fluoride Nanofibers Modified with Titanium Dioxide

Moscow University Chemistry Bulletin - A piezoactive nanofiber composite PVDF film with TiO2 nanoparticles included in it was synthesized by electrospinning. The composition, morphology and...     

A multiwavelength low-pressure radiation source based on argon and xenon chlorides

The characteristics of an excimer radiation source pumped by a subnormal dc glow discharge in an Ar/Xe/Cl₂ mixture with the source operating in a spectral range of 160–310 nm were studied. The emission intensities of the 175, 236, 258, and 308 nm bands due to the transitions ArCl (B-X), XeCl (D-X), Cl₂ (D′-A′), and XeCl (B-X), respectively, were optimized in relation to the pressure, composition, and discharge current of the mixture.     

Optical characteristics of a repetitively pulsed low-pressure discharge in a krypton-freon-12 mixture

Results of a study of the plasma radiation of a repetitively pulsed discharge in a Kr/CF₂ Cl₂ mixture (P≤1.5 kPa) in the 130–300 nm spectral range are presented. Spatial, spectral, and temporal characteristics of the discharge are studied in a spherical anode-plane cathode system, in which the repetitively pulsed mode is established due to the evolving instability of the glow discharge. It is demonstrated that a discharge of this type can be used for the development of a repetitively pulsed low-pressure bactericidal lamp which emits in the band system of KrCl (222 nm) and Cl₂ (257, 200 nm) in the 180–270 nm spectral range.     

Studies of the parameters of a transverse volume discharge in a Ne-SF<Subscript>6</Subscript>-C<Subscript>6</Subscript>H<Subscript>14</Subscript> mixture

Results are presented from studies of the electric and emission parameters of transverse volume discharges in neon-sulfur-hexafluoride-propane mixtures at a total pressure of 3–12 kPa. The spatial characteristics of a transverse volume discharge, the plasma radiation spectra in the 130- to 550-nm wavelength range, the waveforms of the discharge voltage and current, and the yield of carbonic products of propane decomposition are investigated at different pressures and different composition of the Ne-SF₆-C₆H₁₄ mixture.     

Influence of the iodine vapor pressure on the output characteristics of a UV low-pressure gas-discharge lamp

The influence of the iodine vapor pressure on the output characteristics of a UV lamp pumped by a longitudinal glow discharge is studied. The lamp is filled with a helium-iodine mixture to a pressure of 100–1500 Pa. In the spectral range 320–360 nm, the I₂(D′ → A′) band with a peak at 342 nm prevails, while in the bactericidal range, iodine atomic lines at 183.0 and 206.2 nm dominate. The power of the UV lamp is optimized according to the iodine vapor pressure and working mixture composition by numerical simulation.