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21.
Chuncheng Hao Zuolin Cui Yansheng Yin Zhikun Zhang 《Journal of nanoparticle research》2002,4(1-2):107-110
Nanostructured Fe3Al intermetallic compounds were produced by using hydrogen arc plasma method. The transmission electron microscopy experiments showed that the average particle size of the as-synthesized was about 40-nm. The change in hardness of Fe3Al nanostructured intermetallic compounds with annealing temperatures was observed and evaluated. 相似文献
22.
23.
Ana M. Piloto 《Tetrahedron》2006,62(39):9258-9267
Four carboxylic fused furans are presented as new fluorescent labels for the amino and hydroxyl functions of organic molecules. Various representative l-amino acids were chosen as models, labelled at their N-terminus and also at their side-chain. Fluorescent derivatives were obtained in high yields, and their absorption and emission properties were studied. 相似文献
24.
Nusselt number correlations for heat transfer to small spheres in thermal plasma flows 总被引:1,自引:0,他引:1
Seven different equations predicting heat transfer rates to small spheres in plasma flows are examined considering argon and nitrogan as plasma gases from 300 to 21,000 K at 1 atm. For argon there is a general consensus up to 9000 K, beyond which wide deviations in behavior occur. For nitrogen, the seven correlations are in good agreement up to 4000 K, but show substantial deviations beyond this value. Comparisons with the sparsely available experimental data are made for argon from 300 to 17,000 K and for nitrogen up to 5500 K. Disagreement between the various correlations and experiment can exceed one order of magnitude. 相似文献
25.
利用气体放电双探针法研究了等离子体的I-V曲线中的电流I相对于电压V轴交点的不对称性,并提出2种可能的解释:一认为是由于两探针表面积不同引起的;二认为是由于探针所在处等离子体电位不等引起的.本文利用仪器的工艺误差和调换放电管电压的方法,对提出的2种可能原因分别进行验证,并指出第二种解释的合理性,并对其进行了理论分析. 相似文献
26.
27.
Summary Oblique propagating magnetohydrodynamic waves with various wave forms and amplitudes are observed both at the Earth's foreshock
and at comets. The possibility of interpreting some observational results in terms of nonlinear evolution of one- and two-dimensional
hydromagnetic waves is investigated. For this purpose both analytical and numerical techniques are employed. It is found that
an initial monochromatic wave changes its polarization giving origin to magnetosonic shocks and rotational discontinuities;
the time evolution of density-magnetic-field correlation is studied, as a function of the plasma parameters and of the propagation
angle. In the two-dimensional case both a transverse instability and a self-focusing effect may take place. Moreover, a two-dimensional
magnetosonic solution is found, in which the density fluctuations are driven by the total pressure fluctuation as in a one-dimensional
simple wave. These theoretical predictions compare well with the features observed in the solar-wind waves.
Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990. 相似文献
28.
医疗和危险废物高温洁净热处理及环境力学 总被引:3,自引:0,他引:3
结合2003年中国的突发危害公众健康的事件,分析了医疗、化学战剂及危险废物的分类、特性,比较了各种高温热处理技术的基本要求,方法分类和设备特点,包括:各类焚烧炉、热解炉和等离子体裂解装置.还对前处理工艺要求,尾气处理工艺等进行了分析讨论,讨论了防止二次污染的技术手段,特别介绍了二噁英等高危险性产物的特性.还介绍了发达国家的医疗废物和危险废物的管理、处置和二次污染防治等情况. 相似文献
29.
The patterns of absorption and reflection of an ultrashort laser pulse by a plasma with a solid-state density, which are realized in the mode of the normal skin effect, are studied. It is shown that a decrease in low-power pulse duration shorter than the period corresponding to the fundamental frequency of radiation leads to an increase in the absorption coefficient. If the pulse power is so high as to provide electron heating during a time shorter than the reciprocal fundamental frequency, nonlinear suppression of absorption takes place and the spectrum of the reflected radiation contains odd harmonics of the fundamental frequency. 相似文献
30.
We propose that the suppression of J/ψ production in relativistic heavy ion collisions may be explained by that J/ψ dissociates via absorbing multi-gluons in the environment of quark-gluon-plasma (QGP) where abundance of gluons is expected. 相似文献