丁腈橡胶5171密封件热氧老化研究

开展了腈橡胶5171热氧老化试验,结合老化前后宏观、微观性能的变化,对其热氧老化行为及规律进行了研究。结果表明,老化前期,丁腈橡胶5171的物理力学性能出现了较大幅度下降,表面氧元素相对含量及分子链交联密度明显增大,说明橡胶发生了以交联反应为主的吸氧老化;随着老化时间的延长,表面碳元素相对含量上升,氧、氮元素相对含量下降,说明防老剂D和增塑剂癸二酸二丁酯发生了向表面的扩散和迁移,进一步劣化了橡胶的性能。     

高原高寒物资保障环境与对策分析

由于特殊的地理、气象、社会环境,高原高寒地区作战的形态具有相当的特殊性。从自然、地理和社会经济环境等方面对高原高寒地区进行了分析,通过系统全面地分析并结合现代作战特点,有针对性地提出了高原高寒地区保障方法及其效率提高的途径。     

炭系导电填料对瓦斯封堵材料性能影响研究

针对目前煤矿中频频发生的透水事故与静电引发瓦斯灾害的现状,文章以聚合物水泥、阻燃剂以及导电填料制备出一种适用于煤矿井下能够防止煤壁渗水和封堵瓦斯气体的材料,具有防水、防火、抗静电的特点。系统考查了导电云母粉、石墨、炭黑等多种导电填料及其不同配比的混合填料对涂层干燥时间、表面电阻和吸水率等性能的影响,试验结果表明,添加导电云母粉涂层的电阻值变化不大,无法达到国家煤安标准MT 113-1995的抗静电要求,不适合作为导电填料;添加石墨粉的涂层在质量分数为16%左右时电阻值方可达到106¹08Ω;添加炭黑的涂层粘度较大,且质量分数在5%时可达到要求。当石墨粉与炭黑单独添加时,随着导电填料的增加,材料的吸水率逐渐升高,防水性能逐渐下降;从涂膜的抗静电性能和防水性能两方面考虑,最佳的导电填料为石墨与炭黑的混合填料,且最佳的混合比为炭黑:石墨=2:3。     

废弃混凝土在干混砂浆中的应用研究

废弃混凝土的循环再生利用已日益成为人类关注的重要话题,符合环境保护与可持续发展战略的迫切要求。利用废弃混凝土破碎产生的再生细骨料部分取代天然细骨料来配制干混砂浆。通过试验证明:在固定配合比条件下,再生骨料替代率为50%时,干混砂浆抗压强度、保水率和抗冻融性、强度损失率等均符合M5.0中保水的指标要求。     

光电化学阴极保护的原理及研究进展

简要介绍了光电化学阴极保护技术的基本原理以及其影响因素,总结了历年来该方面的主要研究成果,并简要地介绍了笔者课题组在光电化学阴极保护方面的部分工作。最后,对光电化学阴极保护技术进一步的发展以及应用进行了展望。     

Dynamic material flow analysis of steel resources in Korea

Material flow analysis (MFA) is an evaluation technique that systematically identifies the flows and stocks of materials within predefined spatial and temporal boundaries. In this paper, the steel resources in Korea are investigated using dynamic MFA. Iron ore and steel scrap are added as raw material components during the production processes of steel, which is then used in a variety of product groups such as construction products, transportation equipment, machinery/metal products, electrical/electronic devices, and other products through fabrication and manufacturing processes. When such product groups are discarded, they are either recycled or landfilled. With consideration for the lifetimes of various product groups in conjunction with steel resource flows in Korea, dynamic MFA is conducted on the flows of steel stock change and annual scrap generation. By 2020, these two flows are expected to increase by as much as 40% and 30%, respectively, compared to 2008, with transportation equipment, in particular, envisaged to experience high growth. At the current recycling rate, however, it will be hard to meet future scrap demand. According to the scenario analysis, 100% of this future scrap demand can be supplied domestically if the recycling rate is increased to over 70% for all product groups, except construction products and transportation equipment, which already have high recycling rates. By 2020, the reduction in scrap importation costs is projected to offer a financial gain of 2.3 billion dollars.     

The separation of reinforced cementitious composites with a stream-line cutting tool

The paper provides a model for the cutting of reinforced concrete members with stream-line cutting tools. The model is an extended version of the energy model originally developed by Momber and Kovacevic (1995) for hydro-abrasive machining. The model allows the stepwise calculation of the energy absorbed during the cutting of the two parts of the compound - steel bar and matrix material. Hydro-abrasive cutting tests on different cementitious composites are performed in order to verify the numerical results. It is shown that the cutting process can be subdivided into four cutting stages whose locations depended on the energy locally available at the erosion site.     

电袋复合除尘技术的试验研究

通过对电袋复合除尘器性能试验及对喷吹清灰过程的研究,分析了荷电粉尘对滤料过滤性能的影响,探讨了高强滤料的研究开发及电袋复合除尘器的大型化技术等问题。     

面向污染场地的环境修复功能材料

在回顾环境功能材料研究进展的基础上,将材料按功效分为固化/稳定化材料、氧化还原剂类材料以及催化剂类材料,重点对固化/稳定化材料进行了介绍。根据环境材料科学的发展前沿提出了污染场地环境修复功能材料的发展趋势,并总结了功能材料开发与应用中的一些问题。     

某桥墩承台病害分析与处理

桥墩病害的正确分析处理,事关桥梁的安危。介绍了某桥墩承台病害,分析了产生病害的主要原因是混凝土碱骨料反应。据碱骨料反应产生的条件,提出了桥墩承台病害采用优料加大截面隔绝法的处理方案,经由实施,使桥梁重获新生。所提桥墩承台病害处理方案正确,处理效果良好,对类似桥墩的分析处理具借鉴意义。