量子阱中类氢杂质束缚能的压力效应

本文采用变分法研究了量子阱中类氢杂质的束缚能的压力效应，尤其在阱较窄的情形下，其压力效应更为显著．     

Functional magnetic resonance imaging of amphetamine craving

The aim of this study is to identify the brain activity associated with amphetamine craving for understanding the neurobiology of addiction by watching pictures of happy, sad or amphetamine. Brain activity was measured in 12 amphetamine addicts and 12 healthy subjects by fMRI while the subjects watched pictures designed to elicit happy feelings, sad feelings, or the desire to use amphetamine. The result demonstrated that amphetamine cues led to abnormally high cingulate and low frontal lobe activation in amphetamine addicts, who showed abnormalities in affect-related brain activation.     

用于人机交互的交流式电磁跟踪系统的研究

虚拟现实系统和计算机仿真系统中广泛采用电磁跟踪系统测量用户的头部或手部的位置和姿态来实现人机交互。本文分析了目前已有的直流式电磁跟踪系统的不足，提出了一种采用交流信号作激励源的交流式电磁跟踪系统，研究了该系统的结构，推导了用于提取传感器接收信号的递推数字互相关算法，讨论了算法参数与算法性能的关系。仿真实验证明了算法的有效性及理论分析的正确性。本文的研究成果为实际的交流式电磁跟踪系统的设计提供了理论依据。     

背越式跳高教学中应用多媒体技术的实践与探讨

在背越式跳高教学中实行多媒体组合教学 ,改进传统单一的教学方式 ,加深了学生对技术本质特征的理解 ,经教学实验对比 ,教学效果明显提高 .并具体分析探讨了开展多媒体教学的优越性和重要性     

对异步机数学模型中一些问题的研究

本文推导异步机在d、q、O系统中的磁链方程时,将气隙磁场与漏磁场分开考虑,并根据各自特点采取了不同的处理方法,从而简化了推导过程,考虑到异步机与同步机及一般化电机在结构上的差异,在研究异步机的功率平衡时,利用等效电路的概念,进一步阐明了瞬变过程中异步机的功率平衡关系。     

磁畴形成的原理探索

本文运用量子力学和固体物理学分析铁磁物质及其磁畴形成的原理     

复线电气化区段施工感应电对人体的危害及防护对策

感应电会对人体造成伤害。从电磁感应和静电感应原理入手，分析了产生感应电的过程，并就如何防止感应电的危害提出了防护对策，有一定实用价值。     

The genetic diversity of cen-tral and peripheral popula-tions of ratlike hamster(Cricetulus triton)

The impact of habitat fragmentation and isolation on the genetic diversity of populations has attracted much attention in studies of meta-population and conservation biology. In this work, using the randomly amplified polymorphic DNA (RAPD) technique, we studied the genetic diversity of central, peripheral and peninsular populations of ratlike hamster, which were collected in five locations of the North China Plain and its surrounding areas, in 1999. The study revealed that, ⅰ) the genetic diversity of central population of Raoyang County＞the sub-central populations of Gu'an County and Taikang County＞the peripheral population of Shunyi District＞the peninsular population of Mentougou District; ⅱ) the genetic diversities of the five populations were positively correlated to the nearest distances to the peripheral line of population distribution; ⅲ) there were significant differences of gene frequencies of some RAPD fragments among the five populations. More RAPD fragments disappeared in peripheral populations than in central or sub-central populations. The frequencies of two RAPD fragments were correlated to the latitude. This study clearly indicated that the variation of the genetic diversities of the five populations was caused by edge effect and frag- mentation through the enhanced inbreeding and genetic drift, and thus supported the view that habitat fragmentation and related edge effect reduce the population genetic diversity.     

化学镀镍过程中金属基体的引发催化特性研究

通过电位-时间曲线的特征,研究了化学镀镍反应初期不同基体材料的催化特征.在同质基体上可以瞬间诱发化学镀反应,而在异质基体上的诱导期因镀液组成不同而发生变化.在异质基体材料中,Pt无催化活性,Pd的诱发时间最长.