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801.
地铁盾构坍塌事故中施工人员安全能力分析 总被引:1,自引:0,他引:1
地铁项目大规模建设的同时,灾难性的施工事故不断发生。施工人员的不安全行为是事故发生的直接因素,但是,不安全行为正是安全能力匮乏的外在表现。施工人员安全能力的强弱直接影响到是否发生施工事故。在构建施工人员安全能力模型的基础上,分析了施工人员安全能力的形成机理。同时,通过分析地铁施工事故原因,认为地铁施工人员安全能力的大小就体现在施工人员感觉到事故隐患、做出事故隐患危险判断,进而对事故隐患进行正确响应的过程中,并对导致盾构法坍塌事故的事故隐患进行了分析。最后,以一个实际发生的盾构法施工坍塌事故为例,分析了施工人员安全能力在事故发生过程中的体现,从而准确确定了施工人员出现失误的时段,以保障地铁施工安全。 相似文献
802.
复合功能吸附树脂对双组分萘系化合物的竞争吸附研究 总被引:4,自引:0,他引:4
1-氨基 -2 -萘酚 -4 -磺酸 ( 1,2 ,4-酸 )和 2 -萘酚自不同双组分吸附体系中吸附至复合功能吸附树脂 AL -1上的吸附等温线符合 F reundlich等温模型。1,2 ,4-酸的吸附为吸热过程 ,而 2 -萘酚的吸附为放热过程。固相上的 2 -萘酚几乎不影响 1,2 ,4-酸的吸附 ,而固相上的 1,2 ,4-酸大大削弱了 2 -萘酚的吸附。两种溶质在吸附位点上的竞争为主要作用机制。 相似文献
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关于环境影响评价几个问题的探讨 总被引:3,自引:0,他引:3
通过对传统发展模式下的环境影响评价的分析和探讨,指出其存在的主要缺失;提出可持续发展的环境影响评价需要强化的机制和面临的新课题,对环境影响评价为当前的环境保护服务提出几点可行的建议。 相似文献
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807.
为了及时掌握炼化废水的BOD5值,因此对COD与BOD5之间的相关性进行了探讨试验;COD与BOD5的测定采用国家标准方法,连续20d,用最小二乘法计算COD与BOD5的相关关系式;通过相关式由COD值可求出当天相应的BOD5值,为及时调整污水处理设施提供依据。 相似文献
808.
河北省人为土地灾害及减灾对策 总被引:1,自引:0,他引:1
针对河北省人为土地灾害较重的特点,概述了灾害的类型、分布及其危害,分析了致灾原因,提出减轻灾害、谋求可持续发展的对策。 相似文献
809.
Aluminum and ferric salts are commonly used in municipal wastewater treatment plants(WWPTs) for phosphorus(P) removal. In this study, on-site jar tests were conducted to determine the removal of different P species from the fresh samples in the presence and absence of activated sludge(AS) with different doses of alum, poly-aluminum chloride,and ferric chloride at different p H. The soluble P(SP) concentration in the samples was about 0.63 mg/L. When the mixed liquor containing AS was treated with 8 mg/L of Al, SP could be reduced to 0.13 mg/L, while it was reduced to 0.16 mg/L with only 1 mg/L of Al after sedimentation removal of AS from sample. Chemical analysis determined that AS contained 59.8 mg-P/g-TSS and 43.8 mg-Al/g-TSS and most of the P was associated with the aluminum hydroxide. We discovered that the phosphate in the AS could readily be released from it, which was mainly responsible for ineffective removal of P to low levels in mixed liquor even with very high alum dose. This study provides new insight into the behavior and fate of P in the wastewater treatment plants that use alum to enhance P removal in the final effluent. 相似文献
810.
Yingshuai Liu Yunshan Ge Jianwei Tan Mingliang Fu Asad Naeem Shah Luqiang Li Zhe Ji Yan Ding 《环境科学学报(英文版)》2018,30(3):83-91
Maritime transport has been playing a decisive role in global trade. Its contribution to the air pollution of the sea and coastal areas has been widely recognized. The air pollutant emission inventories of several harbors in China have already been established. However,the emission factors of local ships have not been addressed comprehensively, and thus are lacking from the emission inventories. In this study, on-board emission tests of eight diesel-powered offshore fishing ships were conducted near the coastal region of the northern Yellow Bo Sea fishing ground of Dalian, China. Results show that large amounts of fine particles( 0.5 μm, 90%) were found in maneuvering mode, which were about five times higher than those during cruise mode. Emission rates as well as emission factors based on both distance and fuel were determined during the cruise and maneuvering modes(including departure and arrival). Average emission rates and distance-based emission factors of CO, HC and PM were much higher during the maneuvering mode as compared with the cruise mode. However, the average emission rate of Nitrous Oxide(NOx) was higher during the cruise mode as compared with the maneuvering modes. On the contrary, the average distance-based emission factors of NOxwere lower during the cruise mode relative to the maneuvering mode due to the low sailing speed of the latter. 相似文献