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71.
利用AES、WDS和x-射线衍射等方法,研究了杜美丝表面层、铁镍芯与覆铜层界面的微观结构与特性。结果表明:良好的表面层应由Cu2O和非晶态的硼砂构成;玻璃与杜美丝的润湿性决定于表面层的净化程度和构成及加热条件。 相似文献
72.
J Desaki M Kinutani K Tan-Takeuchi NM Le Douarin 《Canadian Metallurgical Quarterly》1996,45(5):448-452
The migration of leucocytes through the walls of venules was examined in detail in the posterior latissimus dorsi muscle of quail-chick spinal cord chimeras, in which flaccid paralysis of the wings was observed. Examinations were made from the 70th to 80th day after hatching. Muscle fibers were degenerated and intramuscular nerve bundles destroyed. Massive leucocytes (almost lymphocytes) were found around the venules, depending on the passage of wandering leucocytes through the endothelium. Lymphocytes penetrated and were encased in the cytoplasm of the venular endothelial cell, and did not pass through the interendothelial junction. These findings suggest that, in the venules of the atrophied chimeric muscle, wandering leucocytes in the blood may pass through the endothelial cell body and migrate into the inflamed extravascular space. 相似文献
73.
A. T. Sousa P. S. Fialho C. A. Nieto de Castro R. Tufeu B. Le Neindre 《International Journal of Thermophysics》1996,17(3):551-560
The density of HCFC 141b has been measured at several temperatures between 260 and 320 K, Mid pressures up to 20 MPa, with a mechanical oscillator densimeter. The densimeter was calibrated with 2,2,4-trimethylpentane, whose density was obtained from a correlating cyuation with 0.3% uncertainty. The density data obtained for HCFC 14H) hits a reproducibility of 0.05% and an uncertainty of 0.3%. The data obtained were fitted to a Tait-type equation. which reproduced the experimental densities within 0.11 % and were compared with the data obtained in other works.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado, U.S.A. 相似文献
74.
75.
目前,微波低噪声放大器设计中采用的Rn-Gn噪声模型只适用于高频、窄带和源导纳(Gs≠0)情况,其应用范围有限,特别是不适用于低频段的低噪声放大器设计。本文对文献[1]提出的En-In噪声模型作了改进,使其不仅适用于高频、窄带,而且也适用于低频、宽带放大器的低噪声设计。进而推导出放大器En-In噪声模型与Rn-Gn噪声模型的等价关系,给出放大器En-In噪声模型的测量方法及实测结果。 相似文献
76.
本文对激光光束通过望远系统后光束的变化进行了分析,并对6倍望远镜进行了激光损伤和破坏的实验研究,实验结果表明,激光对望远系统的损伤破坏主要是热效应所致,损伤破坏的情况与激光的能量,波长,脉冲宽度和望远系统的结构有关。 相似文献
77.
D. Le Masne 《Geothermics》1985,14(5-6)
Within the framework of an EEC project involving ten European laboratories, research on the application of several electric and electromagnetic methods to a geothermal field (Travale, Tuscany), has been undertaken by the B.R.G.M. The objective was to refine the conceptual model of the Travale field and, therefore, to describe the morphology of the basement (down to 2 km depth) and of the Rhaetian reservoir covered by impermeable series.The method best suited to this type of prospection appeared to be electrical dipole — dipole profiling, combined with a 2-D interpretation. Contrasts at more than 2 km depth (500 m long dipoles) could be seen and compared to the depths measured in the boreholes. The EM Melos method (Syscal equipment) should be improved (lower frequencies) to increase the depth penetration. It is, however, a good complementary method for the surface layers. An attempt at a computational interpretation of the self potential profiles gave promising results. To make full advantage of the bipole — dipole measurements efforts should be devoted to their computational interpretation. 相似文献
78.
现场地质预测与决策技术 总被引:1,自引:1,他引:0
油气的生成、运移、分布、成藏、保存具有规律性,技术人员可以依据其规律性对地下地质情况进行推理、预测和决策。钻井过程的现场地质预测技术方法主要是外推法、因果法和直观法三大类。外推法是常用的预测方法,包含了岩性、沉积旋回、标志层、标准层、重矿物等岩石地层学对比方法和生物地层学方法及地球物理方法。现场地质预测与决策是通过确定预测目标、收集相关资料、进行对比分析、形成地质预测结果、拟定地质决策方案、方案优选、方案实施等环节来完成。该技术是现场地质监督的核心技术,在实践中取得显著成效。 相似文献
79.
The International Telecommunication Union (ITU) has completed work on a series of standards on asynchronous transfer mode (ATM) equipment functional operations and network element management. The objective of these standards is to enable flexible design and interoperability of network elements for use in a global ATM network, independent of any specific implementation. This article discusses these standards with respect to their development and application in planning ATM networks. Specifically, it addresses the following: the modeling approach taken in the development of the ITU standards, key operational features specified in the ATM network element functional model, and the capabilities of the ATM network element management interface. Examples of ATM equipment are provided to illustrate how the functional models specified in the ITU standards may be used by network planners and equipment manufacturers to specify and develop ATM equipment tailored to specific needs, while ensuring network interoperability. The article concludes with some points on the future enhancement of these and related ATM equipment operations standards 相似文献
80.
针对我车间Ø450/Ø1150-1200四辊冷轧机由于电动-机械压下系统压下电机老化而停机的现状,提出改电动-机械压下系统为计算机控制的液压压下厚度控制(HAGC)系统,从而恢复该轧机的生产. 相似文献