两种型面轮轨滚动接触蠕滑率/力的比较

本文从数值方面详细分析了两种型面轮对和轨道在滚动接触过程的接触几何、蠕滑率和蠕滑力。在利用Kalker三维弹性体非赫兹滚动接触理论进行轮轨蠕滑力分析时，首先利用有限元方法确定了因轮轨的弹性变形而引起轮轨接触点处的弹性位移差。并利用弹性位移差修正Kalker理论中由Boussinesq和Cerruti公式确定的力和位移的影响系数，使本文的数值过程能考虑到轮轨结构变形对轮轨接触斑的影响。通过计算分析可知，在轮对运动状态相同的情况下，磨耗型轮对和轨道之间的力学行为与锥型轮对和轨道之间的力学行为相比，存在较大差异。数值结果有助于进一步分析轮轨之间的磨耗、滚动接触疲劳和轮轨使用寿命，为采取相应措施提供理论依据。同时发现目前我国铁路所采用的1/40轨底坡与目前正在全面推广使用的磨耗型轮对不是处于最佳匹配状态，有待进一步改进。     

发电机用DJL350磁极钢板的开发与应用

本文论述了高强度冷轧磁极板的试制性研究，应用性研究及在开生桥机组上的实施。通过与国外材料的对比，研究了材料的化学成分、力学性能、磁性能、金相组织及其与性能的关系。并对其实际应用效果进行了分析总结。     

单片机在监控同步电动机运行功率因数中的应用

介绍如何利用单片机自动控制同步电动机运行时的功率因数。     

微絮凝接触过滤处理低浊度含藻水的研究

通过现场试验，对微絮凝过滤处理生活用水所带来的一系列问题进行了详细、科学的分析，在大量试验数据基础上对产生问题的原因进行了研究并取得了初步结论。在此基础上，提出了改进措施，取得了实效。     

对异常高压层厚度划分问题的探讨

通过对喇嘛甸油田800多口聚合物井、更新井的厚度划分及对15口井的异常高压层处理的实例，根据异常高压层在电测曲线上的反映特征，准确地将异常高压层识别出来，并采用本井上下相似层对比法、周围邻井砂体预测分析法、新老标准相结合法等综合分析判断方法，正确地划分异常高压层的厚度，将漏划或少划的厚度补划上。给后续的油层对比、水淹层解释、射孔方案的编制及动态、开发综合方案的调整提供准确的基础数据，并为套管损坏的防治、新钻井的异常高压层厚度解释提供了可借鉴的依据。     

REHEATING TEMPERATURE CONTRAST AND MICROSTRUCTURES OF 7075 Al ALLOY CAST BY LIQUIDUS SEMI-CONTINUOUS CASTING

In this study, reheating of liquidus semi-continuous cast billets of 7075 Al alloy was carried out in a resistance furnace, and the temperature contrast of the outer and the center of the reheated billets was investigated, then the reheating microstructures were investigated. Results show that: the difference of temperature between the outer and center is small and the difference of their microstructures are also small. During reheating at 576℃ the spheroidization of grains is significant after 5min and no rosettes are visible after 20min by optical microscopy. Similar observations were madeon materials reheated at 596℃, but the ripening process is faster. The grains growup to 30-60μm, fine enough for thixoforming.     

微生物提高采收率技术在吉林油田的应用研究

介绍吉林油田筛选微生物菌种、菌种分类、菌种性能评价等室内研究技术和微生物放大发酵工艺、注入工艺。综合评价微生物采油现场试验研究及试验效果，讨论微生物在地层中的生长繁殖、运移及提高采收率机理。图2表5参9（李羡春摘）     

纳米4-H碳化硅薄膜的掺杂现象

对纳米晶SiC薄膜进行了P和B的掺杂,B掺杂效率比P高,其暗电导预前因子与激活能遵守Meyer-Neldel规则,并有反转Meyer-Neldel规则出现.掺杂效率比非晶态碳化硅薄膜高是纳米碳化硅薄膜的特点之一.非晶态中的隧穿和边界透射对输运有一定贡献.     

Formation and investigation of epoxy intumescent compositions modified by active additives

Results are reported of research on intumescent composites based on epoxy resin cross‐linked with polyethylene polyamine and containing ammonium polyphosphate and such modifying additives as calcium borate, manganese dioxide, nickel, and chromium, containing tubulenes as gas‐formers and carbonization stimulators. The changes in composition and physicochemical properties of modified compositions under conditions of heat and fire were investigated by X‐ray photo‐electron spectroscopy, atomic force microscopy, and local force spectroscopy. Ammonium polyphosphate mainly stimulates carbonization processes on the inner surface of a bubble being formed during foam coke formation. The introduction of metal‐containing tubulenes leads to the formation of fire‐retardant and low flammability‐compositions with high coke and carbon structures content. The use of calcium borate in the compositions considerably increases the strength of foam coke being formed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1477–1483, 2002