中碱值硫化烷基水杨酸钙的制备及性能研究

介绍了一种碱值达170mgKOH／g以上、硫含量大于3．0％、钙含量大于6．0％的硫化烷基水杨酸钙盐润滑油添加剂的制备过程及其性能。实验中重点考察了促进剂及硫磺加入量对产品碱值及硫含量的影响；通过冷冻蚀刻电镜法观察了含碳酸盐的胶体粒子结构及粒度分布情况；应用凸轮挺校、四球试验机等考察了硫化烷基水杨酸钙盐产品的极压抗磨性能。结果表明，硫化烷基水杨酸钙产品不但具有良好的高温洁净性、抗氧化安定性、胶体稳定性，而且具有突出的极压抗磨性及热稳定性。     

加强道德教育培养时代新人

一、加强德育的必要性 道德是调节人与人、人与社会、人与自然的关系规则,道德以利益为基础,以个人自律、社会舆论为监督,在我与他的关系(包括他人、他物)中,对自我行为进行合理的选择.     

Effect of RE－Al－N on Structures and Properties of M2 Cast High Speed Steel

M 2highspeedsteel (M 2steel)isamaterialwidelyusedintoolsanddies[1,2 ] .M 2steelischarac terizedbyalongsolidificationrangeandcomplexeu tecticreactions ,whichresultsinsegregationofalloy ingelementsandformationofseveraldifferenttypesofcarbidesduringsolidification[3,4 ] .Forconventionallyprocessedhigh speedsteels ,itisinevitablethatacoarsecarbidenetworkwillbeformedduringsolidifi cation .Coarseprimarycarbidestendtoresultinun evencarbidebandsdistributionafterasubstantialamountofhotprocessing[5] .Ma…     

多部件设备维修问题研究及遗传算法求解

合理组织设备维修，缩短设备维修时间是生产运营管理的一个重要环节。本文探讨了多部件设备维修的有效组织问题。考虑到维修工人对拆分后设备的不同部分具有不同的维修效率，提出了一种基于维修时间优化的决策方法，将其与经典指派方法进行了比较；进一步地，对这一NP-hard问题设计了遗传算法，通过数值例子讨论了其求解有效性。     

Convergence of simultaneous perturbation stochastic approximation for nondifferentiable optimization

We consider simultaneous perturbation stochastic approximation for function minimization. The standard assumption for convergence is that the function be three times differentiable, although weaker assumptions have been used for special cases. However, all work that we are aware of at least requires differentiability. We relax the differentiability requirement and prove convergence using convex analysis.     

Competitiveness of Inexperienced and Experienced Contractors in Bidding

This paper tests the assertion that experienced contractors are more competitive than inexperienced contractors by measuring the effect of experience on bidding competitiveness for building contracts procured by a regular client. Contractors are grouped into experienced and inexperienced contractors, and two levels of contractors’ experience are identified: (1) bidding experience only and (2) bidding plus construction experience. Results of two-sample t tests show that experienced contractors are more competitive than inexperienced contractors. Contractors’ competitiveness in respect of school contracts and other contracts are further compared in evaluating the relationship between the project type and experience effect. Experienced contractors are, on average, more competitive in competing for school contracts. It emerges that the factor of project type familiarity amplifies the experience effect. A comparison of experienced contractors’ competitiveness in bidding for (1) new building works and (2) alteration and extension works shows that the effect of experience would be more significant when contract works packages are highly standardized.     

阻燃沥青的研究进展与建议

介绍了对沥青进行阻燃处理的必要性、沥青的阻燃机理、常用阻燃剂的特性及其作用模式;参照塑料材料阻燃性能的测试手段介绍了常用的沥青材料阻燃性能的测试方法;最后分析了我国沥青阻燃的研究现状,指出了该领域存在的主要问题,并给出了相应的建议。     

GIS中矢量图形的结构分析与VC++中的实现

简要讨论了GIS各类矢量图形元素间的空间拓朴结构及基位置关系 ,并用VC 6 . 0及MFC具体分析了圆弧与多边形区域的相交关系及实现。为利用VC开发专用图形软件提供了有用帮助。     

一个基于优化的有限元模型修正方法

本文提供了一个基于一阶搜索优化的有限元模型修正方法。它只需利用结构模态试验的部分固有频率，就能获得较精确的有限元模型。文中附有某无人机上垂尾有限元模型修正的实例。根据上垂尾前二阶试验的固有频率，采用本文方法，对有限元模型进行了修正。修正后有限元模型的前二阶固有频率与试验值的相对误差在2．35％以内，而第三阶固有频率与试验值的相对误差仅为5．81％。它不仅大大地缩小了用修正前有限元模型算得的固有频率与试验值的相对误差，而且还能较精确地预测无试验结果的高阶固有频率值。     

Aroused problems in the deposition of diamond-like carbon films by using the liquid phase electrodeposition technique

Hydrogenated diamond-like carbon (DLC) films were prepared by using liquid phase electrodeposition technique. The effects of the applied potential and the carbon sources on the deposition process and film structures were studied. It has been found that the organic liquids with high dielectric constants, small viscosities and the methyl group bonding to the polar group are appropriate carbon sources. The increasing of potential improves the formation of sp³ carbon during the deposition process. In a high electric field, organic molecules are polarized and reacted on the surface of the electrode, turning out DLC and other products. It is believed that the reaction follows a polarization-reaction mechanism.