排序方式: 共有29条查询结果,搜索用时 14 毫秒
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网球这种交互式对抗的运动,交叉优势类型的运动员占据优势。网球运动中交叉优势意味着正手会占据优势,交叉优势决定了正手时的视野优势,在现代网球中,正手是王道,是最重要的武器。 相似文献
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洪少春 《泉州师范学院学报》2007,25(4):38-40,72
研究了Andreev反射和交叉Andreev反射的物理过程,分析Andreev反射和电子的正常反射在物理图象上的区别,讨论这两种过程对量子输运性质的影响,并得出了铁磁金属-非磁半导体-超导体结构中自旋相关电流的具体产生过程及其他结论. 相似文献
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Based on the theory of gearing and the gear generating mechanism, this study investigates the contact characteristics of conical involute gear pairs with crossed axes. The meshing model with a reference rack as intermedium is established and tooth contact analysis (TCA) is performed to examine the meshing and bearing contact of the conical involute gear pairs composed of a pinion and a gear. Using the contact line of reference rack tooth surface, the path of contact is confirmed, and the calculation formula of principal direction, relative curvature, path of contact and ellipse of contact are derived. Finally, numerical examples are provided to demonstrate computational results and test gears are made for tooth-bearing tests. The conclusion verifies that the theory is applicable. 相似文献
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通过对广东省番禺市城镇污水的调查研究,获得了三角洲河网地区城镇污水的水量、水质变化特征以及水污染特征:工业废水地域分布趋于分散,行业分布更加广泛,排放总量逐年递减;生活污水排放总量逐年递增;城镇污水中,污染物含量较低,BOD5/CODcr比值偏小;大量未经处理的城镇污水的直接排放以及河网地区潮流的顶托作用,使该地区部分河段水质恶化,进而影响到水源地水质.针对上述问题,提出了7条污水治理对策,以探讨实施三角洲河网地区区域水环境可持续发展战略的途径 相似文献
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互联网络RCP(Ringed Crossed cube Petersen)拓扑结构被提出后并没有给出组播算法.本文利用RCP(n)网络的正则性、良好的可扩展性,以及比Qn,HP(n),RHP(n)网络直径更短和构造开销更小这些特性,按照构造组播树的方法,给出了RCP(n)网络的组播路由算法,并对该算法作了性能分析. 相似文献
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JIANG Xiao-chun LI Ze-lin YIN Jian-jun 《黄冈师范学院学报》2007,27(6):26-29
A new electrochemical oscillatory system of bromate in alkaline solution is reported.In Pt-Bromate-Alkaline solution system,two different types of electrochemical oscillations(Type Ⅰ and Type Ⅱ) can be observed.Type Ⅰ appears before hydrogen evolution and Type Ⅱ involves periodic hydrogen evolution.Type Ⅰ relates to the adsorption/desorption of the hydrogen on platinum electrode,and Type Ⅱ with periodic oscillation stems from the coupling of electrochemical reactions(the reduction of bromate and evolution hydrogen reaction) with mass transfer(diffusion and convection).More over,under the right conditions,the two types appear in different oscillatory modes,for example,simple periodical mode and mixed one,etc..Crossed cycle in the cyclic voltammograms,which is the basic characteristics for electrochemical oscillatory systems,has also been observed as expected. 相似文献
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R Sridharan 《Resonance》2005,10(9):37-52
Cohomology theory is a powerful mathematical tool. This theory applied to topology is a part of algebraic topology, which
associates algebraic invariants to topological spaces. In this article, we give a brief outline of group cohomology.
R Sridharan has been an Adjunct Professor at the CMI, Chennai since retiring from TIFR, Bombay in 2000 where he was a senior
professor. He is also an INSA senior scientist now. His scholarship permeates to literature (English and Sanskrit) and philosophy
as well. Many of the algebraists in the country were his students.
Dedicated to my teacher S Eilenberg 相似文献