成就动机的激发与维持在体育专业足球教学中的实验研究

运用麦克利兰的成就动机理论，采用文献资料法、问卷调查法、实验对比法和数理统计的方法，在高等师范体育教育专业足球教学中进行激发与维持学生成就动机的实验研究．结果表明：实验班成绩优于对照班，且有显著性的差异．在足球教学中激发与维持学生的成就动机，可以有效地提高足球教学的效果和学生的足球成绩．     

挠性结构模型的频域极大似然法辨识

在构建的以压电陶瓷为执行器、电阻式应变片为传感器的挠性悬臂梁物理实验系统基础上,优化设计多正弦辨识输入信号,利用频域极大似然法辨识得到了整个系统的数学模型,并根据该模型进行了数字和物理控制仿真,验证了模型的有效性.良好的控制效果表明:对于挠性结构,频域极大似然法是一种有效的模型辨识方法.     

基于Fourier变换非一致间距阵列的一种合成法

基于阵列图及其分布间的Fourier关系，作者提出了非一致间距阵列的一种合成方法。在Fourier关系下，通过抽样一个给定的阵列图，就能使用FFT(快速Fourier变换)得到其近似连续的阵列分布。为提高改善阵列图的性能，提出一个算式用于决定非一致间距阵列的空间间隔，从而在合成的阵列中保持更多的能量。该方法简单且易于应用。     

Efficient expression of human factor Ⅸ cDNA in liver mediated by hydrodynamics-based plasmid administration

The transfection of plasmid DNA into mammalian cells is an indispensable tool in the study of gene transfer and gene function. Since the original report in 1990 on the successful expression of a reporter gene in muscle[1], plasmid DNA injection has been widely used to mediate gene transfer study. As a gene transfer vector, naked DNA has many obvious advantages. It is easy and cheap to be prepared and more safe after transfection. But the plasmid mediated gene expression is low because of t…     

铂(II)与胺类配合物的合成、晶体结构和抗肿瘤活性研究

研究铂(II)与三种胺类配合物的合成、晶体结构和体外抗肿瘤活性,化合物1的X-射线单晶结构分析表明:这是一个很少见的具有四方锥几何构型的铂(II)配合物,顺式平面四方形配位的铂的轴向上有第5个配位原子。其抗肿瘤活性实验显示3个配合物对几种研究的癌细胞都有较强的抑制作用。     

Reproductive Biology and Prospects for Conservation of Caldesia parnassifolia (Alismataceae)——A Threatened Monocot in China

0　ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｉｓｍａｔａｃｅａｅｉｓａｃｏｓｍｏｐｏｌｉｔａｎｆａｍｉｌｙｔｈａｔｃｏｎｓｉｓｔｓｏｆ 11ｇｅｎｅｒａａｎｄａｐｐｒｏｘｉｍａｔｅｌｙ 95ｓｐｅｃｉｅｓ[1] .Ａｌｌｔｈｅｓｐｅｃｉｅｓｉｎｔｈｉｓｆａｍｉｌｙａｒｅａｑｕａｔｉｃｏｒｓｅｍｉ ａｑｕａｔｉｃｗｉｔｈｔｈｅｍａｊｏｒｉｔｙｏｃｃｕｒｒｉｎｇｉｎｔｈｅＮｅｗＷｏｒｌｄ .ＴｈｅｇｅｎｕｓＣａｌｄｅｓｉａｉｓｒｅｓｔｒｉｃｔｅｄｔｏｔｈｅＯｌｄＷｏｒｌｄｆｒｏｍＡｆｒｉｃａａｎｄＭａｄａｇａｓｃａｒａｎｄＳ…     

Instability of the shear layer in the near wake of a circular cylinder

The instability of the shear layer separated from a circular cylinder is studied with the Reynolds number (Re) of 3000～104 by numerically solving the two-dimensional Navier-Stokes equations. In the wake of the cylinder, primary vortex shedding with natural frequency fs occurs, and the instability of the shear layer with frequency ft develops, which leads to mixing layer eddies and interacts with the primary shedding vortices. However, there remains some uncertainties regarding to the variation of the shear layer characteristic frequency with the Reynolds number. Based on the previous experimental work, several relationships of ft/fs with Re has been proposed including ft/fs～Re0.5 by Bloor, ft/fs～Re0.87 by Wei and Smith and ft/fs～Re0.67 by Prasad and Williamson. The objective of this study is to predict reasonably the relation of the shear layer instability frequency with the Reynolds number based on the present accurate calculation with the high-order schemes and high-resolution spectrum analysis. According to our calculated results, a variation for the normalized shear-layer frequency of the form ft/fs～Re0.69 is predicted numerically, which is in good agreement with a recent experimental measurement of Re0.67 and physical prediction of Re0.7.     

电弧喷涂铝及铝-锌涂层在动态腐蚀介质中的耐蚀性研究

对钢铁基体表面电弧喷涂铝及铝锌涂层进行了动态腐蚀实验 ,以失质量法计算了腐蚀速度 ,并探讨了腐蚀机理。采用SEM对铝及铝锌涂层腐蚀前后的外表形貌进行了观察 ,并对铝及铝锌涂层表面进行了能谱分析 ,采用电化学系统测试了涂层的自腐蚀电位。实验结果表明 ,在 3 %NaCl水溶液中铝涂层的耐蚀性优于铝锌涂层 ;其原因是铝涂层表面上氧化膜的自愈能力及自腐蚀电位高于铝锌涂层。研究还表明 ,铝及铝锌这些阳极涂层不仅能有效地保护它所覆盖的钢铁表面 ,还能保护暴露于腐蚀介质中的钢铁基体表面。在铝、铝锌涂层上刷涂有机涂料 ,有机涂料能渗透到金属涂层的孔隙中 ,将孔隙封闭。同时 ,有机涂层和金属涂层能构成复合涂层 ,其防腐效果更佳     

二维装配图的快递交点排序裁剪算法

提出一个任意多边形的快速交点排序线裁剪算法,该算法简单快捷,效率高,并将其成功用于工程装配图的二维消隐。解决了大多数算法将凹多边形裁剪分解为凸多边形处理存在计算时间长、难度大等问题。     

铑(Ⅲ)与5-NO2-PADAT配合物催化氢波及其应用

在pH4．5的HAc-NaAc缓冲介质中，铑(Ⅲ)与5-(5-NO2-2-吡啶偶氮)-2，4-二氨基甲苯(简称5-NO2-PADAT)生成稳定的紫红色配合物，并在适量的HClO4底液中于-1．03V(vs SCE)处产生灵敏的催化波，据此建立了一种催化极谱法测定痕量铑的新方法。测定铑的线性范围为4．0～130ng／L，检出限为1．4ng／L。