低对称晶体线性电光系数的测量

采用干涉补偿法与椭圆仪法相结合的方法可以测量三斜晶体的全部线性电光系数。本文详细推导了线性电光系数与实验中被测量样品之间的关系,给出了样品加工取向、外加电扬方向、通光方向和入射光偏振方向等实验条件,建立了低对称电光晶体的全部线性电光系数测量方法。     

多功能经济型数控车床十二刀位自动回转刀架

本文就目前国内经济型数控车床回转刀架存在的问题,进行了研究,得到了实现对孔钻、扩、铰、攻丝、套丝、车外圆加工工艺的直线位移坐标驱动的十二刀位立式回转刀架。     

THE STUDY OF ADSORPTION MODEL OF SOME CHEMICALS ADSORBED ON A SILVER ELECTRODE

This paper presents the study of the competi tire and cooperarive adsorption characteristics of pyridine and benzoic acid molecules (ions) on the electrochemically roughened surface of the silver electrode by SERS.     

求目标控制型线性三级规划的罚函数法

利用对偶理论将目标控制型线性三级规划问题转化成目标控制型线性二级规划问题,通过引入对偶间隙,给出了罚函数的概念,并获得了几个相关的性质,并由此建立了一个求解目标控制型的线性三级规划问题的算法.     

基于样本熵的注意力相关脑电特征信息提取与分类

提出一种用样本熵作为特征进行注意力相关脑电信号的分析与分类处理、并采用支持向量机(SVM)算法实现分类器的方法.7位年龄在20~30岁之间的男性受试者接受了执行3种不同注意任务状态下的测试.数据分析结果显示:样本熵分类法对注意任务相关脑电信号分类的正确率可达85.5%,优于传统频段能量法获得的分类精度(77.9%).这个结果暗示了样本熵能有效地识别出自发脑电中注意力相关信息,因而它可在脑电生物信息反馈治疗系统设计中获得广泛的应用.     

Genetic structure and diversity of Oryza sativa L. in Guizhou, China

Preserving many kinds of rice resources and rich variations, Guizhou Province is one of the districts with the highest genetic diversity of cultivated rice （Oryza sativa L.） in China. In the current research, genetic diversity and structure of 537 accessions of cultivated rice from Guizhou were studied using 36 microsetellite markers and 39 phenotypic characters. The results showed that the model-based genetic structure was the same as genetic-distance-based one using SSRs but somewhat different from the documented classification （mainly based on phenotype） of two subspecies. The accessions being classified into indica by phenotype but japonica by genetic structure were much more than that being classified into japonica by phenotype but indica by genetic structure. Like Ding Ying＇s taxonomic system of cultivated rice, the subspecific differentiation was the most distinct differentiation within cultivated rice. But the differentiation within indica or japonica population was different： japonica presented clearer differentiation between soil-watery ecotypes than indica, and indica presented clearer differentiation between seasonal ecotypes than japonica. Cultivated rices in Guizhou revealed high genetic diversity at both DNA and phenotypic levels. Possessing the highest genetic diversity and all the necessary conditions as a center of genetic diversity, region Southwestern of Guizhou was suggested as the center of genetic diversity of O. sativa L. from Guizhou.     

基于TMS320DM642的视频采集系统设计

在分析视频信号采集工作原理的基础上,设计了以TMS320DM642芯片为核心的视频采集方案,给出了其相应的系统结构,选用合适的芯片实现了视频采集的各项功能,满足稳定、实时获取视频图像的需要,并将其应用于贴膜车窗内目标检测的安检项目上.实验表明:该视频采集系统具有数字处理能力强、灵活性高、可移植性好等优点,可广泛应用于图...     

锡林浩特褐煤的钌离子催化氧化

对锡林浩特褐煤进行钌离子催化氧化,氧化产物经重氮甲烷酯化后用GC/MS进行分析,并由此推测原煤的组成结构.结果表明,锡林浩特褐煤钌离子催化氧化产物的主要成份是二元烷酸和苯多酸,由此推测锡林涪特褐煤中含有大量的α,ω-二芳基烷烃和稠环芳烃结构,α,ω-二芳基烷烃的烷基桥链碳原子数分布为C2～C11;苯多酸中苯四甲酸的收率最高,苯五甲酸和笨六甲酸的收率较低,表明锡林浩特褐煤中稠环芳烃结构的缩合程度较低.     

粘钢加固损伤混凝土箱型桥墩的抗震性能Ⅰ:双向拟静力试验

设计制作了11个钢筋混凝土箱型截面桥墩缩尺模型,对其进行了粘钢加固后的双向拟静力试验,分析了加固桥墩的荷载-位移滞回曲线、骨架曲线、延性能力、刚度退化和耗能能力等.结果表明,加固墩柱均发生以弯曲破坏为主的延性破坏,破坏塑性铰由未加固时的墩底上移至加固钢板位置的上边缘,加固后墩柱各项抗震性能良好,表明粘钢加固损伤桥墩是一种有效的抗震加固方式.墩柱强轴方向的滞回环饱满,承载力和刚度较大;弱轴方向的滞回环捏缩效应显著,耗能能力较强.初始损伤程度仅对粘钢加固墩柱的刚度退化及耗能能力具有一定影响.随着轴压比的增大,加固试件的承载力变大,极限变形能力降低,延性能力和耗能能力均增强.而随着长细比的减小,加固试件的承载力变大,极限变形能力降低,刚度退化情况严重.