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981.
P. Bunton M. Binkley G. Asbury 《Applied Physics A: Materials Science & Processing》1997,65(4-5):411-417
Received: 21 May 1997/Accepted: 4 July 1997 相似文献
982.
A systolic array capable of outperforming a table look-up quantiser is proposed. The design has high throughput, can perform uniform or non-uniform quantisation and is suitable for VLSI or field programmable gate array (FPGA) implementation. In the latter case, the array can be used dynamically to both reduce latency and switch between quantisers without the need to reset look-up tables 相似文献
983.
McKinnie I.T. Oien A.L. Wanington D.M. Tonga P.N. Gloster L.A.W. King T.A. 《Quantum Electronics, IEEE Journal of》1997,33(7):1221-1230
The pulsed and CW laser performance of a range of titanium sapphire laser crystals is reported. Titanium ion concentration in the crystals ranged from 0.07 at.% to 0.25 and 0.41 at.% for some recently developed heavily doped crystals. Values of the crystal figure of merit lay between 30 and 220. Threshold, slope efficiency, tunability, and temporal response are assessed. Comparisons are made with the predictions of a simple rate equation model 相似文献
984.
We consider a pseudoparabolic variational inequality in a cylindrical domain semibounded in a variable t. Under certain conditions imposed on the coefficients of the inequality, we prove theorems on the unique existence of a solution
for a class of functions with exponential growth as t → ∞.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 7, pp. 919–929, July, 1998. 相似文献
985.
Films of nonuniform Cu100−xCox alloys with x = 6, 11, 20, and 35 at. %, obtained by electrolytic deposition, are investigated using quantum magnetometry
in fields of up to 5.5 T and temperatures of 2–300 K. In all the compositions a characteristic feature is the deviation from
pure superparamagnetic behavior, which increases as the annealing of the films and their cobalt content increase.
Institute of Solid State and Semiconductor Physics. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3,
pp. 60–62, March, 1998. 相似文献
986.
An investigation was made of the process of Raman scattering of polarized electromagnetic radiation by turbulent fluctuations
in a plasma with a magnetic field. It was found that a turbulent plasma with a magnetic field scatters left- and right-handed
circularly polarized radiation in different ways. The possibility is analyzed of using the results obtained in order to provide
diagnostics for different plasma characteristics in thermonuclear fusion devices employing magnetic plasma confinement.
Institute of Solar and Terrestrial Physics, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya
Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 102–107, April, 1998. 相似文献
987.
Results are presented for experimental studies of the static current-voltage characteristics of tunneling MIS diodes based
on n-type gallium arsenide. It is shown that the forward branch of the current-voltage characteristics can be used to determine
the dependence of the surface potential at the dielectric-semiconductor interface on the voltage and the distribution of the
surface state density over energy in the forbidden band. The results of studies of these dependences for diodes prepared by
thermal annealing at various temperatures are given. The possible causes of changes in the forward and reverse current, and
the dependence of the surface potential on the voltage and distribution of surface state density in energy under the action
on the diodes of a gaseous mixture containing hydrogen are analyzed.
V. D. Kuznetsov Siberian Physicotechnical Institute at Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Fizika, No. 1, pp. 69–83, January, 1998. 相似文献
988.
M. A. Korzhuev 《Physics of the Solid State》1998,40(2):204-205
It is shown that the entropy of crystallization of materials (such as Cu, Ag, Au, and Li) in a “molten” sublattice of superionic
conductors→crystal system may substantially exceed the entropy of crystallization of the same materials from a melt. The observed
behavior explains the known tendency of various superionic conductors to form filamentary crystals (whiskers) in the solid
phase, together with the completely different structure of these whiskers.
Fiz. Tverd. Tela (St. Petersburg) 40, 227–228 (February 1998) 相似文献
989.
S. A. Kazantsev N. M. Firstova L. K. Kashapova A. V. Bulatov A. G. Petrashen' 《Russian Physics Journal》1998,41(12):1258-1262
Polarization data are given for three whiskers recorded with the large solar vacuum telescope at the Baikal Observatory, Institute
of Solar-Terrestrial Physics, Russian Academy of Sciences. The observed degree of polarization varies from 2 to 13%. The direction
of the polarization plane for the mediumintensity whisker was tangential, while that for the weakest one was radial. The brightest
whisker had the polarization plane direction close to radial at the center of the line but tangential at the flanks. It is
assumed that the polarization is due to impact excitation of a hydrogen-atom ensemble in the solar chromosphere by an electron
beam, and estimates are made of the beam energy.
St. Petersburg Fine Mechanics and Optics Institute, St. Petersburg. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii,
Fizika, Vol. 41, No. 12, pp. 85–89, December 1998. 相似文献
990.
M. B. Semenov 《Russian Physics Journal》1998,41(7):705-709
The influence of low-frequency oscillations of the medium on the particle tunneling probability is investigated in a system
with a selected tunneling coordinate, when the two-well tunnel potential takes the form of two parabolas of the same frequency.
With parallel or antiparallel tunneling of two interacting particles, taking the interaction with the medium into account
has no qualitative effect on the process. Quantitatively, however, the medium always influences the parallel motion of the
tunneling particles and does not influence the action along the basic trajectory (R1=−R2) with antiparallel motion of the tunneling particles.
Penzensk State Technical University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 103–107, July,
1998. 相似文献