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81.
We show that the temperature of plasma produced by exposure of copper-zinc alloy specimens to laser radiation changes little
(within the limits of random errors) with a change in the conditions of the laser effect and chemical composition of the specimens.
With use of electric discharges (a low-voltage spark), systematic changes in the temperature of the plasma are observed when
the chemical composition of copper-zinc alloys changes.
Institute of Molecular and Atomic Physics of the National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072,
Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 3, pp. 319–321, May–June, 1998. 相似文献
82.
RESTRICTED FLOWS OF A HIERARCHYOF INTEGRABLE DISCRETE SYSTEMS 总被引:1,自引:0,他引:1
曾云波 《应用数学学报(英文版)》1998,14(2):176-184
1.IntroductionTherestrictedflowsofsolitonhierarchyhavebeenextensivelystudied(see,forexample,[1--7]).Theapproachforconstructingrestrictedflowsofsolitonhierarchycanalsobeappliedtoobtainrestrictedflows(discretemaps)ofahierarchyofdiscreteintegrablesystems(nonlineardifferential-differenceequations)IS,9].TheserestrictedflowshavetheformofLagrangeequationsandthereforecanmodelphysicallyinterestingprocesses.Wesupposethatthehierarchyofdiscreteintegrablesystems(DIS)isassociatedwithadiscreteisospectralp… 相似文献
83.
84.
B. M. Belli 《Il Nuovo Cimento C》1992,15(5):905-909
Summary In this paper we analyse two particularly significant cosmic gamma-ray bursts recorded by the French-Soviet experiment APEX
on board the space mission PHOBOS. The October 24th 1988 event, lasting more than 16 seconds, is among the strongest events
observed up to now. The very high temporal resolution available for its light curve, 1/8 second, allows us to study the power
spectrum density (PSD) up to a frequency range more extended than in the past. The August 10th 1988 event, lasting about 1
second, recorded with a temporal resolution 1/128 second, higher than in the precedent one, permits us to reach still higher
frequencies. We discuss the results of our analysis, comparing them with the results obtained for other events recorded by
precedent space missions, and giving interpretative suggestions.
Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990. 相似文献
85.
We prove that a subset S of vertices of a comparability graph G is a source set if and only if each vertex of S is a source and there is no odd induced path in G between two vertices of S. We also characterize pairs of subsets corresponding to sources and sinks, respectively. Finally, an application to interval graphs is obtained. 相似文献
86.
V.P. Nayyar 《Optical and Quantum Electronics》2002,34(7):697-705
Using statistical approach the author has solved the equations for the mutual coherence function of partially coherent Gaussian laser beams in graded-index fibres. The expressions for the complex degree of coherence and the intensity distribution have also been shown that the self-focusing length inside the fibre depends upon the degree of coherence. The result have been discussed for both conical and cylindrical guides. 相似文献
87.
F. A. Aharonian 《Il Nuovo Cimento C》1996,19(6):981-990
Summary This paper highlights the status of very high-energy (VHE) gamma-ray astronomy with emphasis on the astrophysical significance
of the discovery of TeV γ-radiation from four celestial objects, Crab Nebula, PSR B1706-44, Mrk 421 and Mrk 501, detected
at very high confidence levels using the atmospheric Cherenkov imaging technique.
Paper presented at the Special Session on ground-based gamma-ray astronomy of the XXIV International Cosmic-Ray Conference,
Rome, August 28–September 8, 1995. 相似文献
88.
D.J.E. Knight F. Minardi P. De Natale P. Laporta 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,3(3):211-216
A good frequency standard is required at 1083 nm for measurements on the fine structure of helium and of the fine structure
constant. Several milliwatts of CW frequency-doubled light offers the prospect of stabilisation to a Doppler-free hyperfine
transition in molecular iodine. The 1083 nm emission of an extended-cavity DBR diode laser has been amplified using an ytterbium-doped
fibre amplifier, and applied to a type-I phase matched Mg:LiNbO3 crystal in a high-Q fundamental-resonant cavity for frequency doubling. The amplifier gain at 1083 nm under typical operating conditions was
13.8 dB, with a coherent output power up to 63 mW, limited by the maximum signal input power. The doubling cavity Q was , and about 70% of the incident power was coupled in. The maximum 2nd-harmonic conversion efficiency exceeded 20% and provided
an output power of 3.7 mW for making continuous frequency scans of up to 600 MHz in the green. An optical spectrum analyser
at 541.5 nm showed fringes of 4.6 MHz full width half maximum, close to the instrumental width.
Received: 25 February 1998 / Revised and Accepted: 28 May 1998 相似文献
89.
90.
N-soliton solutions of the hierarchy of non-isospectral mKdV equation with self-consistent sources and the hierarchy of non-isospectral sine-Gordon equation with self-consistent sources are obtained via the inverse scattering transform. 相似文献