Current Distribution Over the Hollow-Cathode Surface for a Low-Pressure Glow Discharge

Russian Physics Journal - The results of an investigation of a low-pressure hollow-cathode glow discharge are presented for the conditions where the cathode cavity depth is comparable with the...     

Plasma Maintenance Mechanisms in Large-Volume Hollow Anode

Russian Physics Journal - The paper presents research into the low-pressure hollow-cathode and hollow-anode glow discharge. The data are obtained for the plasma potential, concentration and...     

Organic conductors based on 2,5-diamino-3,4-dicyanothiophene and diaminomaleonitrile and their transformation to new phthalocyanine analogues

New phihalocyanine analogues were prepared based on 2,5-diamond-3,4-dicyanothiophene and diaminomaleo-nitrile.Department of Organic Chemistry, Slovak Technical University, Bratislava, Slovakia. Institute für Festkörperphysik der Universität Wien, Wien, Austria. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1409–1411, October, 1995. Original article submitted September 24, 1995.     

High-Current Pulsed-Repetitive Electron Accelerator “Sinus-320”: Formation and Diagnostics of a Wide-Aperture Beam

Russian Physics Journal - A wide-aperture (16 cm × 27 cm) source of e-beams for sterilization of plastic packages based on a“SINUS- 320” high-current accelerator with 450 keV...     

Experimental studies of long-lifetime cold cathodes for high-powermicrowave oscillators

Operation of explosive-emission cold cathodes made from various materials was studied at a large number of pulses at current densities of ~1.0⁴ A/cm². The cathode voltage and the beam current were ~500 kV and 5 kA, respectively, with a pulsewidth of ~20 ns. At a small number of pulses (⩽10³), cathodes of like geometry (even made from different materials) demonstrated similar emission properties. For most of the materials tested, with a large number of pulses (⩾10³), the current risetime increased to the fullwidth of the voltage pulse and the maximum current of the vacuum diode decreased. When using a graphite cathode, the maximum current remained invariant until 10⁸ pulses. Mass losses were measured for a series of cathode materials. The results obtained offered the possibility to realize long-lived operation of an X-band relativistic backward-wave oscillator with an almost invariant output power of 350-400 MW during 10⁸ pulses at a pulse repetition rate of 100-150 p.p.s     

Production of nitrogen oxides in a positive column of a glow-type discharge in air flow

This paper deals with the investigations of a low-current glow-type discharge in air flow as applied to the problem of nitrogen oxide production. The electrode configurations correspond to the classical coaxial plasmatron and to the so-called gliding arc. The discharge burns in a regime of constricted positive column with a typical current density from 47 to 120 A/cm² and with the related electron density from 0.53?10¹⁴ to 2.3?10¹⁴ 1/cm³. The gas temperature changes from 3000 to 3610 K. The described conditions provide a flow of NO molecules from the plasma column with the energetic cost for production of one molecule of (30–50) eV. Maximum content of NO molecules [NO]?=?4 g/m³ (3500 ppm) was obtained. In spite of a rather high gas temperature, the plasma is still nonequilibrium. The high vibrational levels of the nitrogen molecules are populated, and the main channel of the nitric oxide production is associated with the reaction in which the vibrationally excited nitrogen interacts with atomic oxygen.

     

Diphenylhexatriene-phosphatidylcholine fluorescence in POPC vesicles: Comparison of the exponential-series and the maximum-entropy methods

We have investigated the time-resolved fluorescence of diphenylhexatriene (DPH) covalently linked to phosphatidylcholine (PC) in palmitoyloleoylglycerophosphocholine (POPC) vesicles with special consideration of the comparison of two methods for distributional lifetime analysis: the exponential-series method (ESM) and the maximum-entropy method (MEM). Generally, both methods were found to reveal equivalent results on high-quality data. Different are the shapes of the recovered distributions (symmetry and width) as well as the time effort for the numerical analysis.