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51.
Shan-Shan ShaoFu-Zhen Xuan Zhengdong WangShan-Tung Tu 《Applied Surface Science》2011,257(23):9915-9920
The closed-form solutions of bending curvature and stress distribution in film/substrate system with the synthesis surface effect are proposed by minimizing the total potential energy. Effects of the roughness and the residual surface stress on stress in film are addressed. Results reveal that, at a given thickness of the substrate, effects of roughness and residual surface stress on the bending curvature become significant with decreasing the film thickness. The roughing surface will enlarge the magnitudes of bending curvature and film stress. The direction change of residual surface stresses can lead to a reversed bending of film/substrate system. 相似文献
52.
L Hui-Yi WANG Tie-Shan HAN Yun-Cheng FANG Kai-Hong MENG Xuan HE Qing-Hua GUAN Xing-Cai LAN Ming-Cong 《中国物理C(英文版)》2011,35(1):26-30
The D(d,p)T reaction in Be metal environments has been measured to investigate the electron screening effect in metals in an energy region of from 5.5 keV to 10 keV in a center of mass system(CMS)at a temperature of 121 K.The depth distribution of deuteron density in Be metals has an impact on the observed reaction yields.A model of deuteron density distribution in metal has been proposed to obtain the original yields.A screening energy of(116±46)eV has been obtained with the assumed deuteron density distribution model. 相似文献
53.
电子信息是信息时代的前沿学科,专业英语是电子信息工程本科课程的重要组成部分.针对专业英语教学中存在的困难与问题,提出了浸入式教学模式,辅以多媒体资料、丰富的教学手段和多样的考核方式,实现了电子信息专业英语浸入式的策略和方法. 相似文献
54.
介绍了利用声学处理软件Adobe Audition 1.5 记录小球自由落体运动的时间,再通过直线运动公式计算重力加速度的方法.该方法可以将运动时间精确到0.001 s, 从而能够更精确地计算出重力加速度. 相似文献
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56.
Elastic-plastic analyses on the residual stresses and curvature of the film/substrate bilayer system
During thermal cycling, the residual stresses are often generated in the film/substrate bilayer due to the material mismatch between the substrate and the film. If the thickness of the film is relatively high, the thermal residual stresses in it may be of different signs. When the film is subjected to elastic-plastic deformation, two plastic zones with different thicknesses may be generated in the film at a significantly high temperature difference. In this paper, a theoretical model which reflects the complete history of thermal residual stresses and curvatures in the elastoplastic film/substrate bilayer system is developed. Solutions are derived to estimate the residual stresses and curvature in the film as functions of temperature difference. The case of Al/Si system is used to illustrate the implementation of this model. Results show that the critical temperature difference at which the second plastic zone near the film surface is generated near the Al film surface is dependent on the film thickness. The strain hardening of the film has an obvious influence on the magnitude of residual stresses within the film at high temperature difference. 相似文献
57.
Effects of carbonization temperature on microstructure and electrochemical performances of phenolic resin-based carbon spheres 总被引:1,自引:0,他引:1
Activated phenol resin-based carbon spheres (APCS) electrodes with high double layer capacitance and good rate capability were prepared from phenol resin-based spheres (PS) at different carbonization temperatures prior to KOH activation. The carbonization temperature has a marked effect on both the pore structure and the electrochemical performances of the APCS in 6 M KOH electrolyte. APCS carbonized at 600 °C results in higher specific surface area and larger pore size, and hence higher capacitance and better rate capability. The specific capacitance of the APCS in 6 M KOH aqueous solution can be as high as 282 F g−1. It remains 252 F g−1 as the current density increases to 1000 mA g−1. 相似文献
58.
ZHOU ShanShi HU XiaoGong WU Bin LIU Li QU WeiJing GUO Rui HE Feng CAO YueLing Wu XiaoLi ZHU LingFeng SHI Xin & TAN HongLi Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate University of Chinese Academy of Sciences Beijing Beijing Global Information Application Development Center Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(6)
Aiming at regional services,the space segment of COMPASS (Phase I) satellite navigation system is a constellation of Geostationary Earth Orbit (GEO),Inclined Geostationary Earth Orbit (IGSO) and Medium Earth Orbit (MEO) satellites.Precise orbit determination (POD) for the satellites is limited by the geographic distribution of regional tracking stations.Independent time synchronization (TS) system is developed to supplement the regional tracking network,and satellite clock errors and orbit data may be obtai... 相似文献
59.
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