精密离心机主轴同轴度测试

本文分析了精密离心机主轴上、下轴承段轴线的空间位置关系,提出了其主轴同轴度的测试方法,并通过实例验证了此方法的正确性.     

精密离心机两正交轴线间的相交度测试技术

本文提出了用经纬仪和固定在轴孔上的两个十字靶标将轴系的回转轴线引出的方法,并通过测试一个轴在0°和180°两个位置时,另一轴的轴线在空间位置上产生的微小变化,计算了两轴线的相交度,并对相交度测试进行了误差分析.     

城市生态系统,城市生态经济系统与城市建设

城市生态系统和自然生态系统一样，也是由环境系统和生物系统组成。城市生态系统注意的是生态效益，而城市经济系统则重视经济效益，从而出现了二者相结合的城市生态经济系统的概念。城市的规划和管理要重视生态经济原则。在城市建设中，要使生态环境建设和经济建设同步进行。我国城市化的具体道路和途径是严格控制大城市，合理发展中等城市，积极建设和发展小城市。     

联用技术在生物体系化合物分析中的应用进展

介绍了目前分离分析生物体系化合物的一般步骤和注意事项.综述了联用技术在生物体系化合物分析中的应用进展情况.展望了联用技术在生物体系化合物分析中的发展方向和应用前景.     

Embedding theorem ofZ-graded Lie superalgebras

The embedding theorem ofZ-graded Lie superalgebras is given and proved. As a subsidiary result it is proved that a transitiveZ-graded restricted lie superalgebm must be isomorphic toW(m,n, 1) if the dimension ofG _i satisfies a certain condition. Project supported by the National Natural Science Foundation of China and the Science of the University Doctoral Program of CNEC.     

A Moderate Deviation Principle for <Emphasis Type=Italic>m</Emphasis>-Dependent Random Variables with Unbounded <Emphasis Type=Italic>m</Emphasis>

In this paper, a theorem on the moderate deviation principle for random arrays under m-dependence with unbounded m is established. This partially extends the results of Chen (Stat. Probab. Lett. 35:123–134, 1997). As an application, the moderate deviation principle for the truncation estimator of the variance in the analysis of time series is obtained.      

广义二阶流体管内轴向流动

在流体的本构关系中引入分数阶导数运算，对于介于粘性与弹性之间的流体的描述更具有合理性。本文将这种关系引入二阶流体，研究其管内轴向流动。我们先求出了１／２阶导数的解析解，用以验证Ｌａｐｌａｃｅ数值反演的ＣＲＵＭＰ方法的有效性。然后用ＣＲＵＭＰ法分析二阶流体管内轴向流动的特征。分析表明粘弹性特征越明显的流体，其速度与应力对分数导数的阶数越具有敏感性。     

Determination of nickel with 2-(2-quinolylazo)-5-diethylaminoaniline as a chromogenic reagent.

A sensitive, selective and rapid method for the determination of nickel based on a rapid reaction of nickel(II) with 2-(2-quinolylazo)-5-diethylaminoaniline (QADEAA) has been developed. In the presence of pH = 6.0 ammonia-ammonium chloride buffer solution and sodium dodecyl sulfonate (SDS) medium, QADEAA reacts with nickel to form a violet complex having a molar ratio of 1:2 (nickel to QADEAA). The molar absorptivity of the complex is 1.38 x 10(5) l mol(-1) cm(-1) at 595 nm. Beer's law is obeyed in the range of 0.01-0.4 microg/ml. This method had been applied to the determination of nickel with good results.