Al_(10)Zn_(2.9)Mg_(1.7)Cu超高强铝合金的喷射成形制备研究

采用喷射成形技术制备了Al1 0 Zn2 .9Mg1 .7Cu高强高韧铝合金沉积坯件 ,研究了喷射成形制备过程中各工艺参数对沉积坯件的成形性、显微组织、致密度的影响 ,确定了适当的工艺参数 ,研究了沉积坯件的热挤压及热处理工艺 ,对材料的组织进行了分析并对不同状态的材料性能进行了比较。研究结果表明 :当喷射成形工艺参数合理时 ,沉积坯件具有良好的成形性与致密度 ,在随后的热挤压过程中 ,通过较低的挤压比即可使材料达到全致密 ;通过对合金进行适当的热处理 ,材料的极限抗拉强度达到 810MPa ,同时延伸率保持在 8%～ 11% ,该材料是一种理想的轻质高强结构材料。     

Beyond Boundary Objects: Collaborative Reuse in Aircraft Technical Support

Boundary objects are a critical, but understudied, theoretical construct in CSCW. Through a field study of aircraft technical support, we examined the role of boundary objects in the practical achievement of safety by service engineers. Their resolution of repair requests was preserved in the organization’s memory via three compound boundary objects. These crystallizations did not manifest a static interpretation, but instead were continually reinterpreted in light of meta-negotiations. This suggests design implications for organizational memory systems which can more fluidly represent the meta-negotiations surrounding boundary objects.     

Ozonation of CI Reactive Black 5 using rotating packed bed and stirred tank reactor

This study investigates the ozonation of CI Reactive Black 5 (RB5) by using the rotating packed bed (RPB) and completely stirred tank reactor (CSTR) as ozone contactors. The RPB, which provides high gravitational force by adjusting the rotational speed, was employed as a novel ozone contactor. The same ozone dosage was separately introduced into either the RPB or the CSTR for the investigation, while the experimental solution was continuously circulated within the apparatus consisting of the RPB and CSTR. The decolorization and mineralization efficiencies of RB5 in the course of ozonation are compared for these two methods. Moreover, the dissolved and off‐gas ozone concentrations were simultaneously monitored for the further analysis. As a result, the ozone mass transfer rate per unit volume of the RPB was significantly higher because of its higher mass transfer coefficient and gas–liquid concentration driving force. Furthermore, ozonation kinetics was found to be independent of the gravitational magnitude of an ozone gas–liquid contactor. Therefore, the results suggest employing RPBs as ozone‐contacting devices with the advantage of volume reduction. The experimental results, which can be used for further modeling of the ozonation process in the RPB, also show the requirement of correct design for the RPB. Consequently, the present study is useful for the understanding of practical application of RPBs. Copyright © 2004 Society of Chemical Industry     

新丰江大坝监测自动化系统的成功实施与现场维护

本文介绍了新丰江大坝监测自动化系统从失败走向成功的实施过程，强调了良好的工作环境以及精心的现场维护在大坝监测自动化应用中的重要性。     

关于重力坝坝内细部构造设计的几个问题

重力坝常采用横，纵缝将坝体分为柱状体施工。为此，横缝须设置止水，纵缝则待坝体冷却后灌浆，将柱状坝块连成整体。此外坝体内部还须设置坝面排水管以消除坝内渗透压力。关于坝内这些细部构造，设计规范仅有原则性要求，一般专业书列举不多，目前有些工程往往参照已建工程的设计图采用，常由于施工详图不祥易发生施工质量问题。根据丹江口重力坝设计经验，对接缝灌浆中的键槽，止浆片，灌浆管道，出浆盒，排气槽及排气管，基岩陡坡     

使用混合杆柱时抽油泵柱塞的超冲程

任何抽油杆柱在理论上都可能产生超冲程，只是大小不同而已。超冲程的存在，使泵柱塞的有效冲程增大，甚至会大于光杆冲程。首次提出了抽油泵柱塞相对超冲程和绝对超冲程的概念，这将有助于正确认识玻璃钢抽油杆的作用和玻璃钢抽油杆的推广使用。将抽油杆柱简化成上端受光杆的激振位移、下端带有集中质量的弹簧－质量力学模型，建立了抽油杆柱纵向振动的偏微分方程和边界条件，然后用固有函数法求解方程，得出了抽油泵柱塞超冲程的无穷级数解析计算式。     

抓紧有利时机 搞好更新换代

本文简要回顾了１５０发动机发展历史，阐述了世界坦克动力发展现状，列举了几种对１５０ 继续发展的看法，认为从综合约束条件和高紧凑性考虑，仍以保持或适当减少缸径较优．指出当 前是追赶世界先进水平的极好时机，要牢牢把握住这个稍纵即逝的机遇．     

可编程控制器在包装机上的应用

本文介绍了可编程控制器（PLC）在包装机上的应用．介绍了系统的硬件设计与软件开发．     

套管固井质量问题及对策分析

从油田现场反应的情况出发，对调整井固井，尾管固井，大位移井套管固井和其他固井的质量问题进行了分析，针对各种问题产生的原因，提出了相应换解决办法。     

地震数据采集系统中频谱均衡滤波器的理论设计

地层的高频吸收衰减效应是导致地震勘探分辨率不高的主要原因，在高分辨率野外地震数据系统中，频谱均衡滤波器所设置的重要部件。文章以频谱均衡滤波器的原理和地层吸收衰减特性为基础，用计算机模拟的方法研究地层吸收衰减使分辨率降低的程度和频谱均衡滤波器对分辨率的补偿效果，给出了较好的频谱均衡滤波器的设计方案。