钢筋网壳锚喷支护修复软岩巷道研究

本文分析了软岩巷道修复支护时围岩的力学特征 ;从理论计算 ,实验室试验和工程实践各方面论证了钢筋网壳锚喷支护在高地应力软岩巷道支护中的优势。     

网壳锚喷支护结构试验研究

网壳锚喷支护是钢筋网锚喷支护的新发展，它将地面大跨度网壳结构与地下锚喷结构结合起来，使支护系统对围岩的内部加固、外部支撑、柔性让压三种能力得到加强，其结构形式、设计理论都有一定创新，通过室内试验，取得良好效果。     

浅谈《环境化学》课程教学改革探索

在全球化背景下,《环境化学》课程教学将是未来培养环境科学专业学生的大趋势。针对当前环境化学教学中存在的实际问题,本文从教材选取、教考模式、教学内容等方面的教学实践中总结经验,以提高学生专业素养为导向,为培养高水平环保人才奠定坚实的基础。     

Hydrogen cold plasma for synthesizing Pd/C catalysts: the effect of support-metal ion interaction

It has been found that cold plasma is a facile and environmentally benign method for synthesizing supported metal catalysts, and great efforts have been devoted to enlarging its applications. However, little work has been done to disclose the influence mechanism, which is significant for controllable synthesis. In this work, hydrogen cold plasma was adopted to synthesize a palladium catalyst supported on activated carbon(Pd/C-P) using H_2 PdCl_4 as a Pd precursor followed by calcination in hydrogen gas to remove the chlorine ions. The Pd/C-P catalyst was found to be made of larger Pd nanoparticles showing a decreased migration to the support outer surface than that prepared by the conventional thermal hydrogen reduction method(Pd/C-C). Meanwhile, the pore diameter of the activated carbon support is small(~4 nm).Therefore, Pd/C-P exhibits lower CO oxidation activity than Pd/C-C. It was proposed that the strong interaction between the activated carbon and PdCl_4~(2-)and the enhanced metal–support interaction caused by hydrogen cold plasma reduction made it difficult for Pd nanoparticles to migrate to the support outer surface. The larger-sized Pd nanoparticles for Pd/C-P may be due to the Coulomb interaction resulting in the disturbance of the metal–support interaction. This work has important guiding significance for the controllable synthesis of supported metal catalysts by hydrogen cold plasma.     

离子液体辅助水热法制备TiO_2/CoFe_2O_4复合材料及光催化性能

以离子液体([C_4MIM]BF_4)为辅助剂、铁酸钴为磁核,用水热法制备了可磁分离TiO_2/CoFe_2O_4新型复合光催化材料。利用X射线衍射、N_2吸附-脱附和透射电子显微镜对样品进行表征;以亚甲基蓝溶液为模拟污染物,在模拟太阳光下考察样品光催化性能。结果表明:加入离子液体制备的TiO_2/CoFe_2O_4样品具有介孔结构,TiO_2稳定的包覆在CoFe_2O_4上,其比表面积可达238.3 m~2/g;在模拟太阳光下照射2 h,对亚甲基蓝的降解率可达97.9%。样品经磁场回收后重复使用3次光降解率为96.1%,依然保持较高的光催化活性。     

高转速发电电动机极间连接线疲劳寿命分析

发电电动机运行特点是机组起停机频繁、工况转换迅速,按照一般技术规范要求每天起停机次数为10次。发电和抽水工况的转换不但会对磁极连接线结构产生很大的载荷和冲击,磁极线圈热膨胀引起的变形也会对磁极连接线的应力产生很大影响。因此发电电动机的极间连接线不但要保证足够的静态安全系数,对于机组起停机、工况转换、甩负荷和飞逸工况还需要有足够的抗疲劳性能。本文针对发电电动机经常采用的几种极间连接线方式进行了对比分析,为今后极间连接线的设计提供了参考和依据。     

鲁地拉水电站进水口通气管制作安装施工技术

鲁地拉水电站进水口坝段通气钢管直径较大，安装难度大，本文详细的介绍了通气钢管制作及安装方法，值得其他类似工程借鉴。     

钢筋网壳锚喷支护结构的研究与应用

根据大跨度空间壳体结构的力学原理，探索和研究井巷钢筋网壳喷层与锚杆组成的一种空间支护结构－钢筋网壳锚喷支护结构，在高地应力软岩巷道中进行工业试验，为高地压软岩巷道提供了一种经济合理，技术先进、安全可靠的新型支护形式。     

电子商务安全的研究分析

本文主要介绍了电子商务的安全目标，并重点介绍电子商务安全性的实现。