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951.
发射场液体推进剂个体防护体系的研究与设计 总被引:1,自引:0,他引:1
为了确保发射场液体推进剂作业人员的身体健康和生命安全,本文以安全系统工程理论为依据,结合液体推进剂作业要求以及防护装具现状,研究并建立了发射场推进剂作业个体三级防护体系。 相似文献
952.
影响运动服装综合舒适性的因素很多,其中,热湿舒适性是评价运动服装舒适性的一项重要指标,它直接影响到人们的健康情况以及运动员在运动项目中的能力发挥情况,成为运动服装面料开发过程中不可忽视的重要环节。本文介绍了运动面料的热湿传递机理,通过分析影响运动服装热湿舒适性的重要因素来探讨运动服装面料的研究现状,并详细介绍了目前已经开发或即将开发的具备热湿舒适性的运动服装面料的种类。 相似文献
953.
<正>1前言近年来,人们为了时尚或美容渴望拥有健康的古铜色皮肤,许多人选择使用日光浴床来晒黑皮肤。人们普遍存在一种错 相似文献
954.
Introduction: China's rapid motorization has resulted in significant challenges in road safety. Method: Using official national statistics, this study examines road traffic injuries (RTIs) experienced by foreigners in China. The number of foreigners entering China has increased 2.4 times over the study period, from 10.16 million in 2000 to 24.33 million in 2008. Results: From 2000- 2008, the number of road traffic fatalities among foreigners similarly increased 2.5 fold, including 49 fatalities reported in 2008. Nonfatal RTIs during this same time frame increased by a magnitude of 1.8 (126 nonfatal injuries in 2000 to 223 in 2008). Conclusions: This study suggests that the total number of foreigners working or visiting China each year who suffer fatal and nonfatal road traffic injuries is relatively low. Impact on Industry: This study provided evidence suggesting that foreigners visiting or working in China face a relatively low risk of road traffic injuries. 相似文献
955.
石化工业由于大量使用可燃、腐蚀、有毒物质,引起的火灾、爆炸及中毒的危险性很大。同时,生产装置大型化、自动化程度越来越高、操作难度越来越大,因此生产装置由于局部小的问题引发连锁反应,形成重、特大恶性事故频率在增加,事故所产生的社会影响在加大,甚至造成国际影响。 相似文献
956.
This study aims to develop a methodology for analysis of characteristics of heavy metals in MSWI fly ash. It performed analysis of composition of heavy metals, leaching toxicity, leaching behavior as a function of pH, specification distribution and corresponding mineral components of residue derived from each step of the sequential extraction. It is found that content of heavy metals follows the sequence of Zn > Pb > Cu > Cr > As > Ni > Cd approximately Hg in both plants, and that total heavy metals account for less than 1% by mass of fly ash. Major hazardous heavy metals in fly ash are As, Cd, Hg, Pb and Zn, whose leaching ratios exceed the limit value described in hazardous waste identification standard. Measured leaching results of Cu, Pb and Zn are essentially consistent with the simulated results at pH between 0 and 13. Content of calcium-silicates, alumino-silicates and glass phases in residue derived from sequential extraction procedure increases steadily from the first step to the fifth step of the sequential extraction procedure. Cu, As, Cr, Hg, Cd, and Ni, relatively stable under strong basic conditions, can be leached out under strong acidic conditions, while Zn and Pb tend to be leached out under both strong acidic and basic conditions. 相似文献
957.
Some major toxic gas release accidents demonstrate the urgent need of a systematic risk analysis method for individuals exposed to toxic gases. A CFD numerical simulation and dose–response model combined approach has been proposed for quantitative analysis of acute toxic gas exposure threats. This method contains four steps: firstly, set up a CFD model and monitor points; secondly, solve CFD equations and predict the real-time concentration field of toxic gas releases and dispersions; thirdly, calculate the toxic dose according to gas concentration and exposure time; lastly, estimate expected fatalities using dose–response model. A case study of hydrogen sulfide releases from a gas gathering station has been carried out using a three dimension FLUENT model. Acute exposure fatalities have been evaluated firstly with a simplified ideal model which assumes workers stay at original exposure location without moving. Then a comparison has been made with a more realistic model which assumes workers start evacuating according to a prearranged course as soon as hydrogen sulfide detection system alarms. These two models represent the worst and best emergency response effects, respectively, and the analysis results demonstrate significant differences. Results indicate that the CFD and dose–response combined approach is a good way for estimating fatalities of individuals exposed to accidental toxic gas releases. 相似文献
958.
The main purpose of hazard and operability (HAZOP) analysis is to identify the potential hazards in the process design which nowadays is generally developed through a computer aided design (CAD) package. Due to the time and effort consuming nature of HAZOP, it is not done in every engineering firm for every design project. To make HAZOP an integral part of process design, an integration framework is proposed in this paper to seamlessly integrate the commercial process design package Smart Plant P&ID (SPPID, Intergraph) with one of the HAZOP expert systems (named as LDGHAZOP) developed by authors. This integration makes it possible to perform HAZOP analysis easily at anytime of the whole lifecycle of a chemical plant as long as the process design is available, which might help the improvement of design quality. One industrial case study is used to illustrate the ability of the integrated system. 相似文献
959.
960.