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141.
A configuration of a plasma flow switch intended for peaking the current of a capacitor bank operating into a liner load has
been proposed and tested where the current bridge and the liner are formed with the help of a single pulsed gas valve. The
design of the load unit has been optimized for the efficiency of the energy transfer from the energy store to the liner. The
peaker was tested in experiments on generation of soft x-radiation and K-radiation of neon. High efficiency of conversion
of the magnetic energy of the primary store to x-radiation has been demonstrated.
Institute of High Current Electronics, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh
Uchebnykh Zavedenii, Fizika, No. 12, pp. 36–40, December, 1999. 相似文献
142.
I. Yu. Sergeev V. M. Sorokin A. K. Yashchenko 《Radiophysics and Quantum Electronics》2000,43(8):619-625
We consider the radiation of low-frequency electromagnetic waves from an axisymmetric current and propagation of these waves in a homogeneous ionospheric plasma with Hall and Pedersen conductivities. We obtain an analytical expressions for the fields excited by pulsed radial and ring currents. It is shown that electromagnetic radiation propagates as a wave inside a cone along the magnetic field. The field propagation outside the cone is described by a diffusion law. The spatio-temporal characteristics of the signal are determined by the ionospheric conductivities. 相似文献
143.
144.
Physics of the Solid State - A crystallophysical model of ion transfer in the superionic Pb1 – xSnxF2 conductor with a fluorite (CaF2) structure is proposed. The... 相似文献
145.
V.?F.?Kopiev V.?V.?PalchikovskiyEmail author I.?V.?Belyaev Yu.?V.?Bersenev S.?Yu.?Makashov I.?V.?Khramtsov I.?A.?Korin E.?V.?Sorokin O.?Yu.?Kustov 《Acoustical Physics》2017,63(1):113-124
The acoustic parameters of a new anechoic chamber constructed at Perm National Research Polytechnic University (PNRPU) are presented. This chamber is designed to be used, among other things, for measuring noise from aerodynamic sources. Sound-absorbing wedges lining the walls of the chamber were studied in an interferometer with normal wave incidence. The results are compared to the characteristics of sound-absorbing wedges of existing anechoic facilities. Metrological examination of the acoustic parameters of the PNRPU anechoic chamber demonstrates that free field conditions are established in it, which will make it possible to conduct quantitative acoustic experiments. 相似文献
146.
V. V. Ratnikov L. M. Sorokin V. I. Sokolov A. E. Kalmykov 《Physics of the Solid State》2009,51(12):2429-2436
Porous silicon layers prepared by anodic etching under different conditions have been systematically studied in the course
of their natural oxidation (aging) in air by many-crystal X-ray diffractometry and transmission electron microscopy. Quantitative
information on the strains and crystal structure of layers has been obtained using a combination of measurements of the 004
symmetric and 224 asymmetric reflections in the Bragg geometry on double-crystal and triple-crystal X-ray diffractometers.
It has been revealed that the aging of porous silicon is accompanied by an increase in macrostrains and microstrains, as well
as in micro-misorientations of crystal fragments, which lead to gradual destruction of porous layers up to their complete
amorphization. 相似文献
147.
Basic equations that describe the conditions of reflection and refraction of bulk acoustic waves at the boundary between acentric crystalline media under uniaxial stress are presented. The effect of uniaxial stress on the anisotropy of reflection and refraction of bulk acoustic waves is numerically analyzed for boundaries of the crystal-vacuum, piezoelectric crystal-piezoelectric crystal, and piezoelectric crystal-elastic isotropic medium types. 相似文献
148.
S. A. Sorokin 《Technical Physics》2009,54(6):805-809
Experiments on compression of an axial magnetic flux by a plasma liner are conducted with the MIG high-current generator.
It is shown that, when the current passing through the liner is about 1 MA, a magnetic field with a strength of up to 50 T
and a duration of 300 ns (in the steady state) can be achieved in a dielectric tube 3–4 mm in diameter that is placed on the
axis. The physics of magnetic field evolution in the tube is discussed. 相似文献
149.
M. I. Lomaev D. V. Rybka D. A. Sorokin V. F. Tarasenko K. Yu. Krivonogova 《Optics and Spectroscopy》2009,107(1):33-40
The amplitude, time, spectral, and energetic characteristics of a volume (diffuse) discharge at an elevated pressure (up to 5 atm) in a gap with an inhomogeneous electric field without an additional preionization source are studied. The concentration and temperature of electrons in the discharge plasma are mea-sured by spectral methods. The effective lifetime of the C 3Π u state of the nitrogen molecule at the trailing edge of the radiation pulse is shown to be determined by radiative and collisional quenchings. For transitions of the second positive system of nitrogen, a plasma discharge radiation power into the complete solid angle is obtained to be ~120 kW, with a specific radiation power of up to ~50 kW/cm3. 相似文献
150.
N. I. Sorokin A. N. Smirnov P. P. Fedorov B. P. Sobolev 《Russian Journal of Electrochemistry》2009,45(5):606-608
RF3 and R0.95Sr0.05F2.95 (R = La, Ce, Pr, Nd) ceramic specimens were prepared by hot pressing at 1173 K under pressure of 3 × 108 Pa for 20 min. The ionic conductivity value was determined by means of impedance spectroscopy in vacuum from 293 to 823 K. For LaF3 at 350 K, the single crystal / ceramics conductivity ratio is about 5. The difference decreases at higher temperature and disappears about 500 K. The ionic conductivity activation energy is 0.30 ± 0.05 eV. For La0.95Sr0.05F2.95, the conductivity of ceramics below 500 K is slightly lower that of single crystals. At T > 500 K, the conductivity values of ceramic and single crystal specimens practically coincide. The ionic conductivity of hot pressed ceramics is about 10?2 S/cm at 500 K and activation energy is 0.25 ± 0.02 eV. 相似文献