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151.
针对磁场变化时激发产生的感生电场很难演示的问题,设计了演示感生电场存在的实验. 该实验将不同功能的仪器组合起来使用,通过亥姆霍兹线圈的交变磁场对带电粒子的作用效果,直观说明感生电场的存在. 相似文献
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《光学与光电技术》2009,7(4):52-52
武汉光电国家实验室李鹏程研究组致力于采用高时间和空间分辨的光学成像方法来研究脑功能活动与神经系统疾病的病理机制。为了实时长时程全场高分辨地追踪中风的发生发展过程,该小组在综合了两种传统微小中风模型(皮层微动脉结扎模型与铜环压迫皮层模型)各自优势的基础上,提出了一种改进的微小中风模型,可以实现将缺血灶定位于特定的功能区域(如大鼠中主管胡须感觉的桶状皮层),并且可以很便利地开展血管再通,从而研究缺血再灌注损伤机制与慢性恢复期的功能重组现象。这种模型将中风病灶定位在特定的皮层表面区域,可以最大程度地发挥光学成像的无损与高分辨优势。这项研究对建立研究功能成像生理基础、再灌注损伤以及中风康复机制的新平台有重要意义。 相似文献
154.
We present the classical solution of Lagrange equations for the black hole with a global monopole or with a cosmic string. Then we obtain the wavefunction of the space-time by solving the Wheeler-De Witt equation. De Broglie-Bohm interpretation applied to the wavefunction gives the quantum solution of the space-time. In the end, the quantum effect on Hawking radiation is studied. 相似文献
155.
We study the quantum dynamics of a single-Cooper-pair box biased by a classical voltage and also irradiated by a single-mode quantized field. We demonstrate that under weak damping of the quantized field, the collapse-revival phenomena can exist in this system, and the oscillations of the collapse and revival depend sensitively on the initial state of the single-mode quantized field and the damping rate κ. We also demonstrate that this system can show the beats phenomena. 相似文献
156.
Vertical and Smooth, etching of InP by Cl2/CH4/Ar Inductively Coupled Plasma at Room Temperature 总被引:2,自引:0,他引:2 下载免费PDF全文
We study the room-temperature dry, etching of InP by inductively coupled plasma (ICP) using C12/CH4/Ar mixtures. Etches were characterized in terms of anisotropy and surface roughness by scanning electron microscopy and atomic force microscopy, respectively. It is found that the flow ratio between C12 and Ctt4, ICP power, rf chuck power, and table temperature can greatly influence the, etching results. By adjusting, etching parameters,vertical sidewall and smooth surface can be obtained simultaneously, together with a moderate, etch rate and a good select ratio. The root-mean-square surface roughness is measured to be as low as 0.27nm. To the best of our knowledge, this is the best result for InP to date. The, etch rate is 855nm/min, and the selectivity ratio overSi02 is estimated to be higher than 15:1. The stoichiometry of the, etched surface has also been investigated by Auger electron spectroscopy. The, etched surface is found to manifest a slight P deficiency, and the ratio between P and In reaches the stoichiometric value within about 0.75nm depth into the surface. 相似文献
157.
分析非晶硅薄膜晶体管在a-SiTFT-LCD中的开关特性,讨论这种开关结构中的主要功能膜材料尺寸与性能参量、光刻制备工艺,存储电容以及栅脉冲延迟效应等对a-SiTFT-LCD的通断电流比,信号响应与保持特性,图像亮度与对比度等光学特性的影响。 相似文献
158.
Experimental investigations of the functional morphology of dragonfly wings 总被引:1,自引:0,他引:1 下载免费PDF全文
Nowadays, the importance of identifying the flight mechanisms of the dragonfly, as an inspiration for designing flapping wing vehicles, is well known. An experimental approach to understanding the complexities of insect wings as organs of flight could provide significant outcomes for design purposes. In this paper, a comprehensive investigation is carried out on the morphological and microstructural features of dragonfly wings. Scanning electron microscopy (SEM) and tensile testing are used to experimentally verify the functional roles of different parts of the wings. A number of SEM images of the elements of the wings, such as the nodus, leading edge, trailing edge, and vein sections, which play dominant roles in strengthening the whole structure, are presented. The results from the tensile tests indicate that the nodus might be the critical region of the wing that is subjected to high tensile stresses. Considering the patterns of the longitudinal corrugations of the wings obtained in this paper, it can be supposed that they increase the load-bearing capacity, giving the wings an ability to tolerate dynamic loading conditions. In addition, it is suggested that the longitudinal veins, along with the leading and trailing edges, are structural mechanisms that further improve fatigue resistance by providing higher fracture toughness, preventing crack propagation, and allowing the wings to sustain a significant amount of damage without loss of strength. 相似文献
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160.
如何利用有限的课时,使人文素质教育取得最大的教育效果,一直是理工科院校努力探索解决的一个重要问题。本文从大学生精神成人的角度,以普世价值观为准则,对大学语文和思想品德课的课程目标进行分析,探索如何把品德课中抽象的理论和大学语文中的生动形象结合起来,力图用熏陶感染代替空洞说教,使学生更容易接受,更好实现教育功能。 相似文献