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941.
提出了利用反转矢量透射反馈算法研制偏振编码光电混合全加器,该加法器可以实现两输入的光学算术运算,研制成的各单元器件可用于其它各种光计算机系统中。 相似文献
942.
G. A. Sokolov N. A. Syagaev Yu. A. Novichkov A. A. Lyashenko 《Measurement Techniques》1994,37(8):863-865
A multifunctional measurement system utilizing a noncontacting, thermal-tracer primary detector is described. It provides for the automatic acquisition of information on volumetric and mass flow rates and the properties of fluid flows.Translated from Izmeritel'naya Tekhnika, No. 8, pp. 10–11, August, 1994. 相似文献
943.
944.
A fundamental research of structural defects induced upon post-growth processing of ZnSe/GaAs epilayers grown on (100) GaAs
was done by identifying defect-related reflections in the transmission electron diffraction (TED) patterns of ZnSe. Structural
artifacts, other than the as-grown defects, on this material system could be excluded according to our results. Four types
of abnormal reflections have been observed in addition to primary reflections. These extra reflections are sensitive to the
post-growth processing of ZnSe epilayers and may arise from various external effects, rather than epitaxy growth, such as
irradiation damage, surface oxidation, and surface contamination. By mapping these reflections at several major zone axes
using TED patterns, we found that the reciprocal lattice for a ZnSe crystal with structural defects consists of two distinct
types of extra reflections associated with irradiation damage. The first type of extra reflections is ±1/3{111} and the other
is ±1/2{111} corresponding to pure-edge and non-edge dislocation loops, respectively. For (100) oriented wafers, the ±1/3{111}
and ±1/2{111} reflections were observed only on two of the four possible 〈111〉 variants (i.e. [111]Zn and [111]Zn)and this phenomenon was attributed to the anisotropy of defect distribution. Extra reflections associated with surface oxidation
and contamination are also observed. The orientation relationships between a surface hexagonal ZnO and a cubic ZnSe film are
[0001]ZnO//[−111]ZnSe, and [01−11]ZnO//[011]ZnSe. The origin, characterization, and elimination of these induced reflections are discussed. With the knowledge about these
extra effects on structural defect formation, we have shown the real microstructure of ZnSe epilayers. 相似文献
945.
946.
Yu. N. Kryuchkov 《Powder Metallurgy and Metal Ceramics》1994,32(11-12):930-934
A method is suggested for calculating percolation thresholds in two- and three-dimensional materials allowing for remote interaction and elongation of particles forming these materials. Calculated results are compared with known data. It is shown that it is possible to use the method when simulating elastic and plastic properties of porous materials. 相似文献
947.
The article presents the results of an experimental investigation of the effect of the temperature, the sulfur content, and
the previous heat treatment on the strength and fracture of the alloy 36NKhTYu under loading by shock waves. The load levels
corresponding to different stages of spalling fracture of specimens were determined in the temperature range from −196 to
750‡C. It was established that heating, increase of sulfur content, and hardening of the specimens lead to an imperceptible
decrease of the dynamic strength of the alloy. The article presents the results of observations of the structure and nature
of spalling fracture of the alloy by optical and electron microscopy.
Translated from Problemy Prochnosti, No. 5, pp. 119–122, May, 1996. 相似文献
948.
Yu. V. Mishchenko 《Measurement Techniques》1996,39(8):832-838
The features of the interference refractometry of turbulent gas flows, which are a special case of a randomly inhomogeneous
medium, are considered. Recommendations are made on the quasi-optimal choice of the parameters of the refractometer system.
Translated from Izmeritel’naya Tekhnika, No. 8, pp. 31–35, August, 1996. 相似文献
949.
S. R. Reid T. X. Yu J. L. Yang G. G. Corbett 《International Journal of Impact Engineering》1996,18(7-8)
This paper is concerned with the problem of pipe whip, the dynamic response of a high pressure piping system subjected to an end force as the result of a pipe break which releases a jet of fluid from the broken section. Both experimental and theoretical results are presented concerning the dynamic elastic-plastic behaviour of cantilever pipes subjected to a transverse force pulse at the free end. Comparisons between experimental data and theoretical predictions are made for mild-steel pipes with outer diameter-to-thickness ratios of 19.5, 28 and 32. It is demonstrated that, for these geometries, the whipping pipes display three characteristically different responses, viz. elastic, plastic hardening behaviour for thick pipes, elastic, plastic hardening-softening behaviour for moderately thick pipes and elastic, plastic hardening-softening-collapse behaviour for thinner pipes. The experimental data taken from a series of high-speed films are compared with the predictions of the instantaneous shapes of the whipping pipes derived from both a rigid, perfectly-plastic, large deflection, dynamic beam model and a more comprehensive model which incorporates the effects of elasticity and plastic hardening and softening, the details of which are presented in the paper. 相似文献
950.
论述作为一种新型发光器件的MIM隧道结的发光机理,报告了该器件的发光现象和I-V特性曲线中负阻现象的实验观察。数据显示,结中表面等离极化激元(SPP)与粗糙度的耦合是引起光发射的主要方面,SPP对隧穿电子的阻塞作用导致了电子输运中的负阻现象。此外,还观察到了直接辐射的紫外峰。 相似文献