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111.
根据Mie散射理论和低浓度近似下,对在红外区高折射率半导体材料作为散射体的蛋白石及反蛋白石能带结构进行了理论研究,发现在浓度为10%,折射率比值大于3.8,无吸收状态下,此类晶体将出现两个能带.同时为此类晶体的能带结构研究提供了一个比较理想的处理方法. 相似文献
112.
合成了一个锰的水杨醛乙二胺Schiff碱的配合物,并分别用元素分析、红外光谱、X-单晶衍射仪等手段对该配合物进行了表征。配合物化学式为C16H14MnN5O2,式量为363.26。配合物属单斜晶系,Pca2(1)空间点群。晶胞参数:a=10.9590(8),b=12.9699(9),c=11.1316(8)。中心离子呈变形的八面体几何结构,与Schiff碱的N、O原子配位,又与叠氮根离子的N原子形成1,3桥连的一维链状结构。 相似文献
113.
INTRODUCTION Turbulent gas-particle flows are frequently found in natural phenomena and industrial processes.Cases of cylinders in cross flows with particles occur in heat exchange equipment,including the convective zone of a fluidized-bed combustor,and in the primary superheaters,reheaters,and economizers of coal-fired boilers.Coherent structures often occur in the above-mentioned gas-particle flow,and have great effect on such different systems,while some features of tur-bulent multiphas… 相似文献
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115.
陈德沛 《河北师范大学学报(哲学社会科学版)》2003,26(4):117-120
在英语中 ,有一些句子形式上是肯定的 ,但却表达一种否定的意义。所以在阅读理解英语文章时要注意语言环境 ,注意那些形肯意否的表达方式 ,切不可望文生义。 相似文献
116.
Bharath Sriraman 《Interchange》2006,37(1-2):151-178
This paper explores the wide range of mathematics content and processes that arise in the secondary classroom via the use
of unusual counting problems. A universal pedagogical goal of mathematics teachers is to convey a sense of unity among seemingly
diverse topics within mathematics. Such a goal can be accomplished if we could conduct classroom discourse that conveys the
Lakatosian (thought-experimental) view of mathematics as that of continual conjecture-proof-refutation which involves rich
mathematizing experiences. I present a pathway towards this pedagogical goal by presenting student insights into an unusual
counting problem and by using these outcomes to construct ideal mathematical possibilities (content and process) for discourse.
In particular, I re-construct the quasi-empirical approaches of six!4-year old students’ attempts to solve this unusual counting
problem and present the possibilities for mathematizing during classroom discourse in the imaginative spirit of Imre Lakatos.
The pedagogical implications for the teaching and learning of mathematics in the secondary classroom and in mathematics teacher
education are discussed. 相似文献
117.
陈金坤 《中国教育技术装备》2003,(7):9-10
液晶分子排列极易受外场的作用而发生变化,从而引起液晶光学特性及其参数的改变,这一特性是液晶在检测、测量和传感方面被广泛应用的原因。 相似文献
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119.
Frølich Nicoline Trondal Jarle Caspersen Joakim Reymert Ingvild 《Tertiary Education and Management》2016,22(3):231-248
Despite striking similarities, the adoption and implementation of policy shifts regarding higher education governance vary considerably across the globe, suggesting a mixed picture of diversification and isomorphism both within and across national higher education systems. By unpacking one particular structural reform process, this paper focuses on mergers as both a governance tool and a governance result in higher education. The paper analyzes the strategic decisions taken by Norwegian higher education institutions during 2014 in the light of a proposed national reform to merge institutions in order to enhance quality in higher education. The empirical basis of the paper consists of analyses of the commissioned self-evaluations of the higher education institutions, and the strategic choices and dilemmas they expressed. The process can be seen as organizational engineering in the sense that it emerges from the self-evaluation process, but is also subject to governancing on the part of the ministry. 相似文献
120.
运用G98W,采用Lan12dz基组,对茂金属配合物[eta^5-C5H4Si2Me5)Mo-Br(CO)3]进行从头算研究,探讨配合物结构单元的稳定性,分子轨道能量,原子净电荷布局规律,以及一些前沿分子轨道的组成特征等,结果表明,标题配合物结构在能量上是稳定的,作为结构单元而存在,为茂金属配合物的合成,分子组装分析提供参考。 相似文献