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901.
In recent years, significant progress has been made to ensure that process industries are among the safest workplaces in the world. However, with the increasing complexity of existing technologies and new problems brought about by emerging technologies, a strong need still exists to study the fundamentals of process safety and predict possible scenarios. This is attained by conducting the corresponding consequence modeling and risk assessments. As a result of the continuous advancement of Computational Fluid Dynamics (CFD) tools and exponentially increased computation capabilities along with better understandings of the underlying physics, CFD simulations have been applied widely in the areas of process safety and loss prevention to gain new insights, improve existing models, and assess new hazardous scenarios. In this review, 126 papers from 2010 to 2020 have been included in order to systematically categorize and summarize recent applications of CFD for fires, explosions, dispersions of flammable and toxic materials from accidental releases, incident investigations and reconstructions, and other areas of process safety. The advantages of CFD modeling are discussed and the future of CFD applications in this research area is outlined. 相似文献
902.
针对神东矿区大柳塔煤矿采用7.0 m采高综采面回采5-2煤三盘区时回采巷道出现不同程度的变形破坏现象,采用现场实测的方法对52304及52303工作面回风顺槽之间的区段煤柱进行了巷道变形及应力变化规律的监测,并运用FLAC3D数值模拟软件对不同埋深条件下两工作面之间区段煤柱的应力分布规律进行了模拟,最后总结分析了回采巷道变形破坏的机理,并得出采空区段煤柱的失稳是造成回采巷道变形破坏的根本原因。从而为巷道的合理布置及相应控制对策的提出提供基础数据,以保证矿井安全高效的生产。 相似文献
903.
利用正交试验方法优化了净化烹饪油污菌种选育的环境和营养条件 ,即 :油 :2 0mL、NaNO3( 2g L) :4mL、KH2 PO4( 0 .5g L) :3mL、微量元素溶液 (CuSO4·5H2 O 0 .0 3g L ,ZnSO4·7H2 O 0 .1g L ,MnCl2 ·4H2 O 0 .0 5g L) :1mL和温度 3 7℃ ;而且得出氮源是影响菌体增长的最重要因素 ,温度是影响微生物降解的重要因素 ,而微量元素和磷源对菌种培育结果影响较小。在此优化条件下选育出了合适降解烹饪油污的c种子菌液 ,其每天可降解油 2 2mg L以上 ,并鉴定出主要的微生物是嗜水性气单孢菌 (Aeromonashydrophila 4AK4)、黄丝藻属 (Tribonema)和多甲藻属 (Peridinium)等菌体 ;分析了选育过程活性微生物、目标污染物和微生物的代谢产物三者之间的关系 ,发现所选微生物能利用油类物质作为碳源进行生长代谢 相似文献
904.
905.
906.
Many substances react with water in such a way that flammable gases are formed. For transport issues this reaction may possess a considerable hazard especially if the cargo is wetted by rain or by water from other sources. In the UN Recommendations on the Transport of Dangerous Goods these kinds of problems are addressed. The UN test N.5 “Test method for substances which in contact with water emit flammable gases” corresponds to this hazard. Classification according to the test method is done by measurement of the gas evolution rate of the flammable gas by any suitable procedure. At BAM a gravimetric approach is used to measure the gas evolution rate. In this paper we present the evaluation of the apparatus by means of an absolute calibration routine utilizing a reaction where a known amount of gas is produced as well as the evaluation of important parameters influencing the gas evolution rate using different substances. It can be shown that the apparatus is capable of measuring absolute gas volumes as low as 6 mL with an acceptable error of about 17% as determined from the reaction of Mg with demineralized water. 相似文献
907.
震害预测的软件程序一般都是基于结构分析的原理,大都采用FORTRAN语言来编写,而震害预测工作中又大量用到分组和排序,这又是数据库语言的特长。本文介绍了在震害预测工作中应用数据库语言的一些体会,主要讨论了两种语言的接口问题。 相似文献
908.
为了迅速、合理地预测和评估洪涝灾害造成的经济损失,为防汛决策提供科学依据,从江苏省洪涝灾害防治的实际需求出发,进行了江苏省洪涝灾情评估系统的总体设计,并阐明了系统的特点,结构和功能。 相似文献
909.
当今社会面临的日趋严重且类型众多的灾害,构成了对生态环境安全的巨大威胁,为此各国都在致力于发挥法制手段在灾害防治中的不可替代的作用。我国是个多灾国家,在减灾法治方面虽已取得了一定成就,但总体上还比较薄弱,因此进一步加强该领域的法制建设十分重要。从我国环境安全保障角度及与国际经验的比较来看,完善我国减灾法制建设的基本工作涉及到减灾法制体系的理论研究、立法模式的选择及其充实方向、行政体制的理顺及执法司法功能的强化等多个方面。 相似文献
910.
Open-focused microwave-assisted extraction and ICP-OES determination of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn from surface sediments of the estuary of Bilbao (Basque Country, North of Spain) was carried out. All the samples were collected at three different tributaries of the estuary (Asua, Galindo and Nerbioi-Ibaizabal) every two months during 1999. The digestion procedure was proposed from the conclusions of a fractionated factorial design, and the precision and accuracy of the method was verified using a certified reference sediment (RTC008-050). The results of the analysis were statistically treated by means of principal component analysis and correlation analysis. The principal component analysis of sediment data (32 samples × 9 metals) indicated different patterns of contamination regarding the tributary and sampling station. The two main patterns observed were a steady increment of the metal concentration along all the campaigns in the samples collected in the Galindo River and a seasonal variation in the Nerbioi-Ibaizabal River, with higher metallic content during summertime and lower content during wintertime. 相似文献