核反应堆厂房的非线性抗震分析

在核工程抗震计算中 ,普遍还是采用线弹性模型进行动力计算 ,但一般结构物在强震中有可能进入弹塑性变形阶段。该文的主要目的是考察结构物在线弹性模型和弹塑性模型下地震响应的不同。以反应堆厂房为例 ,介绍了线性动力算法和非线性动力算法的不同特点 ,计算了厂房在线弹性模型和弹塑性模型下地震响应 ,并对结构响应进行了比较。与线性模型相比 ,弹塑性计算所得到的结构位移和加速度较大 ,但结构内力却相差不多。结果表明 ,采用非线性模型进行抗震计算可以得到更为真实的结构响应 ,可以更加合理地指导结构设计     

论区域经济发展中物流平台的构建

文章阐述了区域经济发展中物流平台的构成要素，构建原则、系统化及其评价标准。     

裂纹试样尺寸对局部解理断裂应力σf的影响

应用弹塑性有限元计算了3种不同尺寸COD试样裂尖前的应力分布.在不同温度下进行了拉伸和COD试验.通过精确测量起裂源距钝化裂尖前的距离,测定了局部解理断裂应力σf.结果表明,在一定范围内随裂纹深度a/h,试样高度h和试验温度的增加,COD和断裂载荷Pf明显变化,而σf基本不变.σf是一个稳定的材料本质参数,它的值不随裂纹试样尺寸变化.     

基于单一数据源的产品BOM多视图映射技术

为实现产品全生命周期中的物料清单 (bill ofmaterial,BOM)信息集成 ,提出了基于单一数据源的产品BOM数据多视图映射技术 ,初步建立了 BOM多视图映射的基本理论和 BOM主要视图间的 BOM映射类型 ,分析了BOM多视图间的数据映射关系 ,基于基元化组件重构理论 ,设计了 BOM多视图数据映射平台和 BOM视图映射工具组件 ,实现了分布式环境下的 BOM主要视图间的数据映射     

Microelement analysis of source of raw materials of terracotta warriors and horses of Qin’s Mausoleum in pits No. 1 and No. 2

In order to search for sources of the raw material of the Qin’s terracotta warriors and horses, we selected 20 samples of pottery warriors and pottery horses of the Qin’s Mausoleum from pit No. 1, 19 samples of pottery warriors and brick from pit No. 2, 20 samples of clays near the Qin’s Mausoleum and 2 samples of Yaozhou porcelain bodies. The 32 kinds of element content of each sample were measured by neutron activation analysis (NAA). These data were analyzed by fuzzy cluster analysis, the trend cluster analysis diagram was obtained. The results showed that samples of terracotta warriors and horses from pits No.1 and No. 2 were closely related to the loam layer near Qin’s Mausoleum, but their relations with the loess layers were not so close, and they were out of all relation to Yaozhou porcelain bodies. Thus, it could be deduced that the Li Mountain clay may be considered as the original place of the raw materials of the terracotta warriors and horses, the kiln sites might be located nearby the Qin’s Mausoleum.     

Formation of calcium phosphate mineral materialcontrolled by microemulsion

In order to prepare calcium phosphate-based material with nano-structure and bioactivity, natural lecithin and n-tetradecane were used as the amphipile and the oil phase respectively, along with the water phase, to form a microemulsion template. Phosphate mineralization was induced and controlled by the microemulsion. The products, characterized by scanning electronic microscopy, infrared spectroscopy and X-ray diffraction analysis, are composed of lecithin and hydroxyapatite, and possess the nano-structure of sticks, balls and three-dimensional nets connected by tubes. These results show that the microemulsion can be used to control calcium phosphate mineralization for the preparation of biomimetic mineral materials with various nano-structures.     

我国物流产业的现状及发展对策(二)

物流产业是国民经济发展的动脉和基础产业。目前，我国物流的社会化、市场化程度仍然很低，在广大中西部地区和边远省份，真正意义上的现代物流尚属空白。我国政府部门要努力营造物流产业发展的宏观环境，加强物流基础设施建设，加快培育具有国际竞争力的现代物流企业，建立和健全企业物流管理组织，作用现代科技进步实现物流现代化。     

三维中心裂纹板中J积分的计算及分析

利用大型有限元软件ANSYS ,对受单向拉伸的中心穿透裂纹板进行了三维弹塑性断裂计算和分析 ,分别得出屈服应力、切线模量、裂纹深度及板的厚度的不同引起J积分值的变化 ,为防断裂设计的选材和结构完整性评价分析提供了理论依据。     

纺织新材料及其在针织生产中的应用

纺织新材料有绿色环保型纤维，差别化纤维、功能性纤维和高性能纤维等，本文简述它们的特性及其在针织中的使用。     

纳米磁性流体的制备及应用技术

纳米磁性流体是诞生于 2 0世纪 60年代末的一种新型的液体功能材料 ,是一种纳米铁磁性微粒在表面活性剂的包覆下 ,稳定地分散在载液中而形成的一种胶体 .介绍了它的磁性、黏度特性、蒸发特性和温度特性等几种主要性质、典型的制备技术以及它在密封、润滑、阻尼、研磨、印刷、医学等方面的应用和发展 ,并提出了值得重视的研究领域以及对纳米磁性流体研究的几点建议 .