冷轧辊的硬度和残余应力在回火过程中的变化规律

本文利用x射线分析法和大截面试样的逐次剥层法研究了冷轧辊在低温回火中残余应力与硬度的变化规律,以及淬硬层与试样尺寸对回火应力松弛的影响。找到了冷轧辊淬火后的合理回火工艺制度。     

Social impact assessment of investment activities in the China–Pakistan economic corridor

In order to analyze potential social risks, and achieve smooth implementation of investment activities in the China–Pakistan economic corridor (CPEC), we attempt to establish social impact and risk indicators. Both the impacts on the projects and the impacts of the projects are used to develop risk indicators in accordance with the literature review, reality and international standard principles. Using an analytic hierarchy process (AHP) and average value to analyze questionnaires of both Chinese and Pakistani respondents, we identify the importance of various risk indicators. The primary social risks of the western high mountain region include tribal obstacles and religious extremism. The social risks to the southeast coastal plains include preserving the historical and cultural heritage of the area and international protection of national parks. The social risks in north Kashmir include disputes, extremist threats, religious and cultural differences, and the protection of natural reserves. The social risks of the Xinjiang region primarily involve social issues faced by ethnic minorities and environmental pressures.     

起爆药生产废水中重金属离子的治理方法

文中对治理重金属污染的化学沉淀法、气浮法、电解法、离子交换法、吸附法、液膜法、反渗透法和电渗析法等技术的特点进行了分析和介绍,重点分析了高效、简便、选择性好的吸附法处理水中重金属离子的特点,其对传统方法不能处理的低浓度重金属废水具有独特的应用价值.     

禹门口提水工程基坑开挖控制爆破

该项工程的开挖爆破中,采用塑料导爆管非电起爆技术等措施,成功地解决了复杂环境条件下的爆破安全问题,为同类工程施工提供了可借鉴的经验。     

基于适应高原环境的武器装备防护包装设计方法探讨

针对典型高原环境特点及其对武器装备的影响,从设计技术要求确定、总体方案选用、功能特性设计和试验设计验证等方面探讨了如何设计适用、可靠的多功能综合防护包装,以提高武器装备的高原环境适应性。     

Water-assisted sub-critical crack growth along an interface between polyimide passivation and epoxy underfill

Direct chip attach (DCA) microelectronic packaging technology is gaining prominence due to its numerous advantages. Delamination (debonding) of the underfill epoxy/ polyimide passivation interface of a DCA during hydro-thermal reliability testing has always been one of the salient problems. We have studied the water-assisted sub-critical crack growth along this interface and our measurement offers important clues as to the origins of the poor hydro-thermal testing results for these interfaces. A modified asymmetric double cantilever beam (ADCB) testing technique has been used to measure the sub-critical crack growth velocity v at various relative humidities and temperatures as a function of the crack driving force (strain energy release rate) G ^*. The presence of a significant partial pressure of water p _H2O produces a marked decrease (by up to a factor of 12) in the threshold G ^* for crack growth at measurable velocities. Above the threshold log v rises linearly with but then enters a regime where the crack velocity (v=v ^*) is almost independent of . Finally, at the values of G ^* corresponding to rapid crack propagation in the absence of water, log v increases very rapidly with G ^*. By analogy to the classic work on water-assisted sub-critical crack growth in silica-based glasses, where very similar features are observed, we believe that the sub-critical crack growth along the polyimide-epoxy interface results from stress-assisted hydrolysis of primary covalent bonds, in our case ester bonds across the interface. The regime of just above the threshold corresponds to a physicochemical situation where the water activity (p _{H 2O} ) at the crack tip is the same as that of the gaseous environment. In the regime where v=v ^* constant, the water activity at the crack tip is below that in the environment and the crack growth velocity is limited by the transport of water vapor to the bonds ahead of the crack tip. We develop a model of this crack growth following Wiederhorn 1967 that allows us to predict the sub-critical crack growth as a function of G ^* for arbitrary relative humidity and temperature conditions.     

湿热环境下开孔复合材料层合板的强度

通过试验研究T300/5405复合材料层合板在6种湿热环境下开孔拉伸、开孔压缩的极限强度,分析了湿热环境对开孔复合材料层合板强度性能的影响,对比了不同湿热环境下材料的破坏模式。在有限元仿真方面,通过考虑湿热环境对材料刚度和强度的影响,建立了湿热条件下复合材料开孔层合板极限强度的预测方法,模拟了开孔复合材料层合板在不同湿热环境、不同载荷类型下的损伤演化全过程。有限元预测结果与试验结果的误差在20%以内,验证了该预测方法的有效性。     

煤矿救灾机器人研究现状及需要重点解决的技术问题

讨论了近年来我国煤矿生产中发生的安全事故和造成的人员伤亡情况,阐述了研发煤矿救灾机器人的重要性和紧迫性,综述了国内外矿井救灾机器人的研究现状,指出了煤矿救灾机器人的研究思路和需要解决的技术问题。     

应用计算机编制煤矿生产计划

矿井采煤计划编制影响因素复杂,是一个多环节的综合决策过程。用单一的优化方法进行优化,难以实现计划的系统优化。运用计算机进行煤矿生产计划编制的实质是应用系统工程优化理论和先进的计算机软件技术,建立一个集工作面地质数据库管理、模型优化、计划编制可视化于一体的综合的采煤计划编制环境。     

体脑疲劳交互影响下煤矿工人作业改善研究

采用主观疲劳评价法,对陕西某矿业公司采煤工人的体疲劳和脑疲劳进行调查与研究,了解工人的工作内容与休息时间。用SPSS软件进行数据分析,得出煤矿工人的疲劳值,分析疲劳产生的原因,并结合实际情况提出相应的建议和解决方案。结果显示,煤矿工人的体疲劳主要发生在腰部、肩膀、前臂和后臂等部位,噪声疲劳和视疲劳是影响工人脑疲劳的主要因素,因而建议对矿工的作业动作进行优化,极大化地改善工人工作环境,优化生产流程和管理制度。目的在于减轻煤矿工人的体脑疲劳,预防人因失误,提升生产过程安全性。