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961.
Sourav Das 《Resonance》2003,8(10):76-84
An analysis of the Madelung constant of the sodium chloride crystal lattice has been made, in an effort to supplement information
available in undergraduate textbooks. A method of approximation of the constant using the personal computer is presented.
An erratum to this article is available at . 相似文献
962.
The study of parasites and their likely influence on optimal foraging and mate-selection in animals has attracted much attention
in recent times. The possible effects of parasites on the host include the manipulation of host behaviour by parasites and
the emergence of host behavioural adaptations for protecting against parasitism. Self-medication in wild animals is believed
to be the behavioural adaptation evolved primarily against parasites and associated diseases. In this article, we have briefly
reviewed some types of unusual behaviour observed inmammals, birds and insectswhich can be considered as self-medication.
Rajasekar Raman is a PhD student in the Department of Animal Behaviour and Physiology, Madurai Kamaraj University. His research
interests include behavioural ecology and conservation of bats. Presently he is studying the roosting ecology of the tentmaking
fruit bat Cynopterus sphinx.
Sripathi Kandula is a Professor in Neurophysiology, Department of Animal Behaviour and Physiology, School of Biological Sciences,
Madurai Kamaraj University. His research interests are in the fileds of echolocation, social organization, mating system,
population genetics and conservation of bats. 相似文献
963.
本文通过少数民族汉语教学的性质、目的、内容以及目前普通采用的教学方法的分析,从语言的本质是音义结合的符合系统,语义在整个交际过程中占居着核心地位的思想出发,提出在少数民族汉语教学中,应当采取语义优先的原则,并具体分析了语义理论在语音、语法教学中的应用。 相似文献
964.
颜振珏 《黔南民族师范学院学报》2008,28(6):7-12
牛顿运动定律以及由牛顿第二定律推导出的动量定理、动量矩定理、动能定理,只适用于宏观低速的情况下,而且在运动的过程中,物体的质量是恒定不变的。然而在宏观低速的情况下,我们会遇到许多变质量物体运动的问题,在此情况下,牛顿运动定律以及由此推导出的三条基本定理将要做一定的修改,其表达式是不一样的。 相似文献
965.
基于课程标准的理念,要达成并维持有益于终身健康的体能水平,传统的体能教育模式有明显的不足之处。文章提出了基于概念的体能教育课程模式,主要讨论体能教育的意涵,基于概念的体能教育课程的特征、优势,该模式的哲学理念以及它如何与体育课程内容标准相对应。 相似文献
966.
进入21世纪以来能源危机日益凸显,加之国家环境保护政策和法规的推行,以电能为核心的清洁新能源的开发利用受到从未有的重视,其中大容量蓄电池的研究和制造成为热门课题。硫酸亚铁是生产电池材料磷酸亚铁锂(LiFePO4)的前驱体材料,对硫酸亚铁中的锌、铅等重金属含量有严格的限制,研究表明纳米活性复合沉淀剂能有效去除硫酸亚铁中的锌及重金属,保障磷酸亚铁锂等电池材料的质量,使硫酸亚铁的应用范围得到拓展。 相似文献
967.
In order to design and retrofit a subway station to resist an internal blast,the distribution of blast loading and its effects on structures should be investigated firstly.In this paper,the behavior of a typical subway station subjected to different internal blast Ioadings was analyzed.It briefly introduced the geometric characteristics and material constitutive model of an existing two-layer and three-span frame subway station.Then three cases of different explosive charges were considered to analyze the dynamic responses of the structure.Finally,the maximum principal stress,displacement and velocity of the columns in the three cases were obtained and discussed.It concluded that the responses of the columns are sensitive to the charge of explosive and the distance from the detonation.It's also found that the stairs between the two layers have significant effects on the distribution of the maximum principal stress of the columns in the upper layer.The explicit dynamic nonlinear finite element software-ANSYS/LS-DYNA was used in this study. 相似文献
968.
本文介绍了如何利用DELPHI中的数据仓库组件开发数据仓库应用系统,为用户提供一种有效的定制的数据仓库应用方式,利用此组件可进行灵活的多维数据分析。 相似文献
969.
Bibliometric maps of field of science 总被引:2,自引:1,他引:2
Irina Marshakova-Shaikevich 《Information processing & management》2005,41(6):1534-1547
The present paper is devoted to two directions in algorithmic classificatory procedures: the journal co-citation analysis as an example of citation networks and lexical analysis of keywords in the titles and texts. What is common to those approaches is the general idea of normalization of deviations of the observed data from the mathematical expectation. The application of the same formula leads to discovery of statistically significant links between objects (journals in one case, keywords — in the other). The results of the journal co-citation analysis are reflected in tables and map for field “Women’s Studies” and for field “Information Science and Library Science”. An experimental attempt at establishing textual links between words was carried out on two samples from SSCI Data base: (1) EDUCATION and (2) ETHICS. The EDUCATION file included 2180 documents (of which 751 had abstracts); the ETHICS file included 807 documents (289 abstracts). Some examples of the results of this pilot study are given in tabular form . The binary links between words discovered in this way may form triplets or other groups with more than two member words. 相似文献
970.
工作艺术是富有创造性的工作,好的思想政治工作体现的就是艺术性,它主要包括:使用语言文字的艺术,疏通引导艺术,果断及时的决策和善于掌握有利时机的艺术,恰当运用幽默的艺术,有效利用制度、规范实施教育的艺术,善于组织会议、提高工作的艺术,科学运筹时间的艺术,强化教育效果的艺术。 相似文献