机动车制动液的研制

介绍了合成型机动车制动液的生产和配方，讨论了物料组成对产品的影响。     

Oxidation and reforming reactions of CH4 on a stepped Pt(5 5 7) single crystal

The oxidation and reforming kinetics of methane by O₂, CO₂ and H₂O were studied on a stepped Pt(5 5 7) single crystal from 623 to 1050 K under methane rich conditions. The rate of carbon deposition was followed by ex-situ Auger electron spectroscopy under non-oxidative conditions. The apparent activation energy for methane decomposition was significantly lower than the apparent barriers measured for both total oxidation, CO₂ and H₂O reforming. Total oxidation of methane to CO₂ and H₂O followed by combined dry and steam reforming (combined combustion-reforming) led to CO production rates which were higher than direct CO₂ or H₂O reforming rates. The enhanced rates are most likely due to the ability of adsorbed oxygen to prevent carbon nucleation and/or scavenge carbon enabling the reforming reaction to turnover on a larger fraction of sites. Comparable amounts of carbon were found by Auger electron spectroscopy measurements after both direct dry or steam reforming, while combined oxidation-reforming had considerable less carbon. During direct dry or steam reforming, CO₂ and H₂O serve only to scavenge adsorbed atomic carbon, while in the presence of oxygen, carbon is removed by both combustion and reforming routes.     

合成正丁烷的一种改进方法

本文论述了一种从正丁醇合成正氯丁烷的改进方法，提高了产率，并用元素分析，红外光谱、沸点、比重和折光率对正氯丁烷作了鉴定。     

大跨双曲混凝土组合扭壳屋盖施工拆模优化分析

由于混凝土抗拉能力较差,双曲组合扭壳抵抗悬垂线方向的主拉应力控制至关重要.如果拆模顺序不当,可能会使壳体结构产生过大的拉应力.为解决此问题,以华工扭壳为例,对平行四边形底面双曲组合扭壳的满堂脚手架施工拆模顺序进行全面优化分析,并与工程实测进行对比,得出较为合理的拆模方式.     

Binding materials of dehydrated phases of waste hardened cement paste and pozzolanic admixture

Fly ash (FA) and ground granulated blast-furnace slag (GGBFS) were added to improve the performances of regenerated binding materials (RBM) which refer to dehydrated phases with rebinding ability of waste hardened cement paste. Flowability tests, compressive strength tests, SEM, TG-DSC, and non-evaporable water content tests were employed to study the performances of the combined binding materials and the interactions between RBM, FA, and GGBFS. Results show that adding FA or GGBFS can improve the workability of RBM paste, and GGBFS has positive effects on strength of RBM. Pozzolanic reactions happen between RBM, FA, and GGBFS. And the activation effect of RBM to FA and GGBFS is superior to that of P.O grade-32.5 cement, especially at earlier ages, because of the high reactive f-CaO existing in RBM. On the advantages of the synergetic effects of RBM and pozzolanic admixtures such as FA and GGBFS, new combined binding materials can be prepared by blending them together. Funded by the National Science Foundation of China(No. 50508034)     

新型钢铅组合耗能器性能试验及参数优选

为了考察新型钢铅组合耗能器(NCSLD)的力学性能和提高其耗能能力,利用电液伺服压剪试验机对NCSLD耗能器进行力学性能试验,采用ANSYS实体建模的方法对耗能器进行大量的数值分析,并对性能试验和数值分析的结果进行对比,研究耗能器的滞回特征参数与其6个几何参数之间的关系,回归出二者之间的公式.提出评价耗能器性能优劣的标准及其附加条件,并以此标准为依据,利用均匀设计法和遗传算法分别对耗能器的6个几何参数进行优选.结果表明遗传算法的选优效果要好于均匀设计法,同时得到一系列性能良好的NCSLD耗能器.     

石油烃、Cu2+单一与复合污染对沙蚕的毒性效应

在实验室模拟条件下研究了石油烃、Cu2+单一与复合污染对沙蚕的毒性效应.试验的结果表明,沙蚕的死亡率与石油烃、Cu2+的浓度呈显著相关关系.其半数致死浓度LC50分别为:30.2～116.26μg/L(石油烃);449.52～1130.34μg/L(Cu2+).沙蚕体内Cu2+的积累量随着暴露溶液中Cu2+浓度的上升而增加,当Cu2+的浓度>500μg/L时,这一变化十分显著;而沙蚕体内石油烃的含量随着暴露溶液中石油烃浓度的升高无显著变化.而Cu2+和石油烃复合污染对沙蚕的毒性作用较为复杂,在不同的处理中,表现出了协同和拮抗两种作用方式.同时,在Cu2+与石油烃复合污染条件下,沙蚕体内Cu2+的积累量也有显著变化.在复合处理组中,当Cu2+的浓度达到500μg/L时,Cu2+在沙蚕体内的积累量与Cu2+单一污染相比,Cu2+在沙蚕体内积累量相比显著降低.     

大口径光学透镜瞬态温度场模拟

为考察热辐射效应对光学元件稳、瞬态温度场的影响,给出了考虑辐射和导热耦合换热情况下复杂几何结构光学透镜稳、瞬态热特性的适体坐标下离散坐标法.对喷管形和圆柱形介质进行计算并与其他方法比较表明,建立的适体坐标系下辐射与导热耦合换热计算方法精度较好.对两端为球缺中间为圆柱的大口径透镜内的辐射与导热耦合换热过程进行了数值模拟.计算结果表明,为了精确地预测半透明介质如透镜内的温度分布,应该考虑辐射与导热耦合作用,且应当考虑介质的光谱特性.     

高速机车车辆的车轴数字化超声波探伤系统

针对高速机车车辆车轴的超声波探伤提出一种新的超声波探伤方案．将组合探头装置安装在车轴的端面上,用机油作耦合剂,准确定位,保证探头在扫查时超声波主声束始终穿过车轴的中心线,使主声束与裂纹相交,便可对车轴进行探伤．该系统检测机车车轴具有准确度高,精度高,效率快的特点．     

重型车辆双路制动液压系统性能仿真

对重型车辆电液伺服控制双路制动器系统进行了分析与设计。采用电液伺服控制的双联制动阀控制双腔制动油缸的双路制动方案,实现车辆的行车制动和紧急制动。通过分析制动器系统各组成模块和连接管路对制动性能的影响,建立了制动器系统的非线性数学模型。应用MATLAB/Simulink对系统的双路行车制动性能进行了仿真研究,验证了设计方案的合理性。台架试验表明:所设计的制动器液压系统的性能达到了设计要求。