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131.
Roald Hoffmann 《Angewandte Chemie (International ed. in English)》1987,26(9):846-878
To make sense of the marvelous electronic properties of the solid state, chemists must learn the language of solid-state physics, of band structures. An attempt is made here to demystify that language, drawing explicit parallels to well-known concepts in theoretical chemistry To the joint search of physicists and chemists for understanding of the bonding in extended systems, the chemist brings a great deal of intuition and some simple but powerful notions. Most important among these is the idea of a bond, and the use of frontier-orbital arguments. How to find localized bonds among all those maximally delocalized bands? Interpretative constructs, such as the density of states, the decomposition of these densities, and crystal orbital overlap populations, allow a recovery of bonds, a finding of the frontier orbitals that control structure and reactivity in extended systems as well as discrete molecules. 相似文献
132.
作为初次参加《高分子物理》课程教学的教师,从听课、备课、上课、课后等方面进行了总结。只有做好这每个环节,并不断提高自身素质,才能逐渐成长为一名合格的专业教师。 相似文献
133.
The mechanism of the anesthetic process is of interest both to the clinician and to the pharmacologist. However, this is still an unsettled issue and a multitude of models have been proposed for the process. Noticing that most models propose either a molecular perturbation by the agents or an effect on some colligative property, we explore in this article the thermodynamical consequences of these postulations. Comparison of these with experimental findings is then made. The comparison shows the inconsistency of many of the models with the facts: (i) it refutes the long accepted conviction, culminated in the unitary hypothesis, that general anesthetics act not at a particular receptor site but invariably on all. Some consequences of this finding are demonstrated. (ii) it implies that a simple phospholipid medium is not feasible as an anesthetic site. (iii) it infers that proteins do have the properties required from anesthetic sites.Dedicated to Prof. Menachem Steinberg on the occasion of his 65th birthday 相似文献
134.
Z. L. Zhang M. H. Zhong J. Liu F. M. Liu Z. Z. Wang F. P. Zhong F. Wu 《Journal of Thermal Analysis and Calorimetry》1999,58(2):421-433
In this work some calorimetric measurements were also carried out on the electrorefining silver by using different current densities with a Calvet type microcalorimeter at room temperature. The ratio (R) of the measured heat (
m) to the input electric energy (
in) and the excess heat (
ex), i.e., difference between
m and
in during the electrorefining process, were discussed in terms of general thermodynamics. It was found that the R and
ex for silver were related with the current density or cell voltage employed in the experiment. The results obtained here also indicate that the heat generation under different conditions, such as different currents or voltages may be caused partially by the irreversibility of the process or by some unknown processes.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
135.
Jean Diebolt 《Journal of Theoretical Probability》1991,4(4):655-667
We consider the Markov chainX
n+1=T(X
n
)+
n
, where {
n
;n1} is a
d
-valued random sequence of independent identically distributed random variables, and the functionT:
d
d
is measurable and satisfies a suitable growth condition. Under certain conditions involvingT and the probability distribution of
n
, we show that this Markov chain is ergodic. Moreover, we obtain sharp upper bounds for the tail of the corresponding stationary probability density function. In our proofs, we make use of the Leray-Schauder fixed-point theorem. 相似文献
136.
通过对静止点电荷系的电力线及波振动的研究,应用MATLAB对其电力线在空同分布的可视化和波的振动叠加及阻尼振动振幅的衰减图象的可视化,能很好地对物理学中那些抽象的知识形象化、具体化,进而通过图形直观地描绘出来. 相似文献
137.
变分法在数学物理问题中有着广泛的应用.把一个数学物理定解问题和一个变分问题联系起来,使之成为泛函的极值问题,使原来需要求解的方程是某一泛函的欧拉—拉格朗日方程.很多物理规律都可以利用泛函极值的方法进行求解. 相似文献
138.
刘小云 《玉林师范学院学报》2005,26(1):12-15
台湾问题是至关祖国统一能否最终实现的关键。建国后,三代领导人就台湾的归属问题作了毫不含糊的表态,并在如何解决台湾问题以及回归后台湾怎样发展等方面进行了不懈的理论探讨和实践探索,充分体现了党与时俱进的创新品质。 相似文献
139.
于月民 《黑龙江科技学院学报》2005,15(6):364-367
考虑几何非线性和非线性压电效应,研究了压电材料作为变形驱动器的压电层合板的弯曲,建立了基于非线性的压电层合板的广义本构方程.利用Ritz法得到悬臂压电层合板的弯曲变形与作用电场间的非线性关系.计算分析表明:在强电场的作用下变形会迅速偏离线性结果,此时必须考虑非线性压电效应,而线性分析只适合于低电场的情况. 相似文献
140.
陈庆林 《湖北师范学院学报(自然科学版)》2005,25(3):111-113
物理教学对学生审美能力的培养作为一种新的教育理念和教育模式,主要是教师在物理教学过程中要将相关因素按美的法则构建为审美因素,重点培养学生的审美感受力、审美鉴赏力、审美创造力。 相似文献