不同大学生学业求助与散打技能形成的文本分析     

吴沛京  吴晓明 《首都师范大学学报(自然科学版)》2011,32(4):91-96

运用文本分析法,以选修《武术散打》课程的两个年级大学生为对象,对网络学堂上大学生的求助问题进行分类评分,用来研究不同大学生学业求助与散打技能的关系.结果表明,是否有求助行为、求助问题的类型与大学生的散打技能形成有比较显著的关系,不同类别的大学生求助表现不同.  相似文献   

高效液相色谱法测定三拗汤制剂中麻黄碱的含量     

宋伟 《贵州师范大学学报(自然科学版)》2011,29(3):138-140

目的建立三拗汤制剂中麻黄碱含量的测定方法。方法采用高效液相色谱法测定三拗汤制剂中麻黄碱的含量,并考察其方法的可行性。结果盐酸麻黄碱在0．0868～0．8680ug（r=0．9999）范围内线性关系良好,加样回收率和RSD为99．5％和2．1％。结论该方法简便、快捷、准确,可用于三拗汤制剂中麻黄碱的含量测定。  相似文献   

煤样试片制备方法对煤水接触角测定影响分析     

闫智婕  陈学习  许鸿雁 《华北科技学院学报》2011,8(2):66-69

在分析研磨法制备煤样测定煤水接触角优缺点的基础上,采用压制煤样试片制备方法,压制了两组具有光滑表面的煤样试片.利用FTA-200新型动态接触角分析仪分别在两组煤样试片表面测定了其接触角,并对测定结果的标准差数值分析,结果表明:在压制煤样试片上测得的接触角比较准确,工作量小,可重复性好.  相似文献   

小波分析用于水稻叶片氮含量高光谱反演   总被引：3，自引：0，他引：3  

方美红  刘湘南 《应用科学学报》2010,28(4):387-393

针对叶片氮营养高光谱诊断中光谱弱信息提取困难的问题,利用小波对作物冠层光谱信号进行分解,提取光谱弱信息建立氮含量反演模型. 在东北平原长春市采集水稻冠层高光谱数据建立氮含量预测模型,并对该模型精度进行检验. 采用Daubechies小波系的Db5函数对水稻原始反射光谱和导数光谱进行8 层小波分解,选择不同尺度和位置的小波系数作为输入参数建立192 个反演模型,分析不同输入参数对模型精度的影响,从中选择对应较高模型精度的输入参数组合建立氮含量最佳反演模型. 实验结果表明,小波系数预测叶片氮素含量模型具有较高的估算精度,预测值与实测值的复相关系数最大为0.99,显著优于传统光谱指数的估算模型精度. 此项研究表明,小波分析在提取反射光谱弱信息反演作物生化成分方面有良好的应用前景.  相似文献   

Flow-induced release of adenosine 5′-triphosphate from endothelial cells of the rat mesenteric arterial bed     

V. Ralevic  P. Milner  K. A. Kirkpatrick  G. Burnstock 《Cellular and molecular life sciences : CMLS》1992,48(1):31-34

Adenosine 5-triphosphate (ATP) was released into the perfusate of rat isolated mesenteric arterial beds during each of two consecutive increases in flow. There was no significant difference between the amounts of ATP released on each occasion. Substance P was also released into the perfusate by increased flow, although its release was more variable. Removal of the endothelium of the mesenteric vessels with sodium deoxycholate led to a significant reduction (74%) in the amount of ATP released compared with the release before the endothelium had been removed. This suggests that the ATP released into the mesenteric arterial perfusate during increased flow arises from endothelial cells.  相似文献   

基于主成分回归分析的瓦斯含量预测     

杨拉蒂  毕建武  贾进章 《世界科技研究与发展》2013,(6):694-696,732

为了增加多元回归模型预测的精度,将主成分分析与多元回归分析相结合提出了PCA—MRA模型,并将该模型用于实际瓦斯含量预测。结果表明,PCA—MRA模型消除了输入变量之间的相关性,减少了输入变量值个数,提高了预测精度,便于实际推广和应用,为瓦斯含量预测提供一种新的途径。  相似文献   

Bovine microvascular endothelial cells of separate morphology differ in growth and response to the action of interferon-γ     

A. M. Fenyves  M. Saxer  K. Spanel-Borowski 《Cellular and molecular life sciences : CMLS》1994,50(2):99-104

Five cell types recently isolated from the bovine corpus luteum differed in their epithelioid morphology and their cytoskeleton, but shared common criteria of microvascular endothelial cells^1,2. To give strong evidence for the separate entity, the growth rate of the 5 phenotypically different cells was studied. They were seeded at low density on day 0. Most of these cells were treated with 200 to 1000 U recombinant bovine interferon- (IFN-) for 3 days. The untreated remainder served as controls. Cell counts were made for all cultures on days 4, 7, 10 and 13. morphology: 13 d after treatment with IFN- senescent cells as well as intact cells occurred in cultures of cell types 1 to 4. Cultures of cell type 5 were apparently unchanged and resembled their untreated counterparts. Desminpositive cells in cultures of cell type 2 developed cell processes. Growth rate: In the absence of IFN-, the growth rate was high for cell types 3 and 4, moderate for cell type 1, and low for cell types 2 and 5. The presence of IFN- caused anti-proliferative effects. These were higher for cell types 3 and 4 than for cell types 1 and 2. IFN- could be cytotoxic on cell type 3. In contrast, the cytokine tended to support the cell growth of cell type 5. These findings substantiate the postulate that endothelial cells exhibiting separate morphology in culture also function differently.  相似文献   

粉质粘土含水量与抗剪强度参数关系的试验研究   总被引：1，自引：0，他引：1  

张存根  张怀静 《华北科技学院学报》2011,8(2):27-29

本文采用常规直剪仪研究了粉质粘土的抗剪强度指标,据此分析了含水量对粉质黏土粘聚力、内摩擦角的影响,得出了土体抗剪强度参数随含水量变化而变化的规律,拟合出了相关的近似公式,结果表明:在含水量小于11.37％时,粉质粘土的粘聚力随着含水量的增加呈幂指数增加;含水量大于11.37％时,粘聚力随着含水量的增加呈线性降低.而粉质...  相似文献   

“以人为本”：《德意志意识形态》的核心内容     

吴晓东 《上饶师范学院学报》2008,28(1):1-4

“以人为本”是马克思、恩格斯合著的《德意志意识形态》的核心内容,具体表现为：它无论哪方面的内容,都离不开人的问题,通篇都表现了“以人为本”的思想。《德意志意识形态》的“以人为本”思想是在对费尔巴哈、鲍威尔和施蒂纳在人的问题上的错误思想的批判中充分表现出来的;其对唯物史观的表述蕴含了丰富的“以人为本”思想,形成唯物史观的基础就是“以人为本”。  相似文献   

构建高师光学课程内容新体系的思考与实践     

陈万金  董连政  华中 《松辽学刊》2006,27(4):88-89

根据高等师范院校的特点，结合教学工作实际，对光学课程的教学内容进行了一系列改革，提出了构建具有高师院校特点的光学教学内容的基本原则和实施方案．  相似文献