ZW系列弯管机床CAD系统的分析及设计

对中频弯管机床的计算机辅助设计系统进行了设计研究。介绍了所研制软件包的功能，综合分析了机床总体受力状态及有关参数间的制约关系，从而完成了机床总体及各部件的子程序模块设计。为满足中频弯管机系列化设计的需要，文中还涉及参数化图形库设计的内容。     

A contribution to the study of the electrochemical oxidation of p-aminophenol on a mercury electrode

The reversibility of the oxidation process of p-aminophenol on a mercury electrode in buffered aqueous solutions is studied. Differential capacity curves are recorded and the number of electrons is determined by chronoamperometry. Kinetic parameters are determined at the foot of the wave.The results obtained are in agreement with the hypothesis that quinoneimine hydrolysis is slower than its diffusion, therefore the former takes place in a homogeneous medium and not in the interphase.     

横张预应力砼梁关键部位受力性能研究

横张法预应力混凝土属于后张有粘预应力混凝土结构,预应力钢筋张拉有别于常规后张法施工。本文利用ANSYS软件对横张预应力混凝土梁在张拉施工阶段的受力情况进行仿真模拟,研究粘结锚固区域和插销定位区域混凝土受力变形的规律,为横张预应力混凝土结构设计和施工提供参考。     

中国建筑业与国际惯例接轨

涉外工程比例的加大，为中外合作提供了更多的机会。合作的内容也从咨询，设计，施工，管理到经营的某相环节扩展至全过程。因此，中国建筑业的发展需要全方位与国际惯例接轨。本文通过工程实例概括介绍一个国际工程的操作方式在报价，招投标，合理管理等关键环节上与国内一般工程的区别。     

论杜威伦理思想中的知行关系

知行关系的问题是伦理学的重要问题,杜威论说的角度与众不同,他认为人类长久以来在寻求确定性和安全感的过程中,造成“知”与“行”分离的传统。这种传统又造成旁观者道德认知模式的局限性。对此,他指出道德知识的特性不在于寻求确定不变的规则和条目,而在于付诸日常的道德行为实践。要实现这种认识,区分道德观念和关于道德的观念是必要的。     

我国钢管工业的现状、问题与发展前景(下)

概要分析了当前我国无缝和焊接钢管生产发展状况,包括生产能力和消费情况;简要介绍了国内主要钢管生产厂家的生产、技术、装备以及油井管、高压锅炉管和核电用管等高端产品的开发情况。针对钢管行业所存在的短期行为、盲目发展、重复建设的严重现象以及一些企业产品结构不合理、质量差、能耗高,生产机制不完善,能源与环保管理水平低等方面有悖国家《钢铁产业发展政策》的问题,提出了相应的发展举措。     

Studies of the hydrogen held by solids: XXII. The surface chemistry of reduced molybdenaalumina catalysts

The surface hydroxyl concentrations of a fresh molybdenaalumina catalyst (8% Mo) and of the alumina from which it was made have been determined as a function of the temperature of pretreatment. Similar data were obtained for catalysts reduced with H₂ or with CO. In all cases, the hydroxyl concentrations decreased with increasing pretreatment temperatures. The difference between the curves for the parent alumina and the molybdenaalumina preparation made from it provided a measure of the number of hydroxyl groups eliminated as the epitaxial monolayer of molybdena was grown onto the surface. The values obtained (1.7 ± 0.6 OH/Mo) showed that the surface hydroxyl groups of alumina are replaced by molybdate anions. When the catalyst was reduced with CO to about $\text{e}\text{Mo}\text{= 1.5}$ (average valence, Mo^+4.5), the curve obtained was almost identical with that for the unreduced catalyst, but when the catalyst was reduced with H₂, values for the retained hydrogen were higher than for the oxidized catalyst and approached those of the parent alumina as its evacuation temperature was increased to 550 °C. This increase in hydroxyl concentration was in agreement with earlier deductions.The hydroxyl region of the infrared spectra of similar preparations was recorded. Four distinct bands could be characterized for the parent alumina at 3780, 3740, 3705, and 3650 cm^?1 and a shoulder at 3795 cm^?1. The same bands were present on the oxidized catalyst, but with lower intensities and with altered intensity ratios; i.e., some bands were affected more than others as hydroxyl groups were replaced by molybdena species. Spectra from catalysts reduced with CO were indistinguishable in the OH region from those for the unreduced catalyst. No new bands appeared when the catalysts were reduced with H₂, but the intensities of bands attributable to alumina OH increased with the 3795 cm^?1 band strengthening noticeably more than the others. Thus, the new hydroxyl groups introduced on reduction are probably alumina OH rather than MoOH as previously supposed. A form of hydrogen which is chemisorbed but which can be removed from the catalyst as H₂ on evacuation at the reduction temperature also appeared in the OH region, mainly as a continuous contribution to the low frequency edge. From absorption coefficients derived from the present data, it was deduced that about twice as many hydrogen atoms were present in the H₂ formed than were supplied by these OH groups; i.e., the chemisorption appears heterolytic with half the atoms unseen by ir. A search was made for a band attributable to MoH, but without success. A brief study was made of this adsorption process, which was found to be slow but reversible, and to have a positive pressure dependence. When the catalyst was reduced with CO, rather than with H₂, a portion of the CO remained irreversibly chemisorbed in electronically comparable amounts. Infrared spectra of such samples contained a band at about 1585 cm^?1 attributable to a carbonate species. Data for the two reducing gases differed in that no reversibly chemisorbed CO was observed. At room temperature, CO was also chemisorbed as a linear species with the stretching frequency (2190 cm^?1) higher than that of the gaseous molecule (2143 cm^?1).     

Description of interaction processes in agitated liquid-liquid dispersions

Phenomenological models are proposed to describe drop breakup and coalescence in a turbulently agitated liquid-liquid dispersion. Based on these models, breakage and coalescence rate functions are developed and used to solve the general population balance equation describing drop interactions in a continuous flow vessel. Parameters of the models are evaluated by comparison with experimental data on drop size distributions and mixing frequencies obtained in a continuous flow vessel over a range of operating conditions. The favorable agreement between experimental observation and the model are encouraging that the model is suitable for predicting dispersion properties such as drop size distributions, interfacial areas and mixing frequencies.     

膨胀套管的研究现状

综述了国内外膨胀套管的研究现状,表明我国在高性能膨胀套管制造技术领域与发达国家之间存在着较大差距;探讨了不同作业类型下膨胀套管用钢的选材、性能要求及组织设计目标;展望了膨胀套管的未来发展趋势及对我国油气勘探开发的重要意义。建议加快高端膨胀套管的国产化研发进程,为我国深海钻井和勘探开发西部油气藏急需的膨胀套管钻井关键技术提供装备支持。