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1.
R. Grosseuvres A. Comandini A. Bentaib N. Chaumeix 《Proceedings of the Combustion Institute》2019,37(2):1537-1546
The present work reports new experimental and numerical results of the combustion properties of hydrogen based mixtures diluted by nitrogen and steam. Spherical expanding flames have been studied in a spherical bomb over a large domain of equivalence ratios, initial temperatures and dilutions at an initial pressure of 100 kPa (Tini = 296, 363, 413 K; N2/O2 = 3.76, 5.67, 9; %Steam = 0, 20, 30). From these experiments, the laminar flame speed , the Markstein length L’, the activation energy Ea and the Zel'dovich β number have been determined. These parameters were also simulated using COSILAB® in order to verify the validity of the Mével et al. [1] detailed kinetic mechanism. Other parameters as the laminar flame thickness δ and the effective Lewis number Leeff were also simulated. These new results aim at providing an extended database that will be very useful in the hydrogen combustion hazard assessment for nuclear reactor power plant new design. 相似文献
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《中国科学B辑(英文版)》2007,(6)
Five polymer bonded explosives (PBXs) with the base explosive ε-CL-20 (hexanitrohexaazaisowurtzi- tane), the most important high energy density compound (HEDC), and five polymer binders (Estane 5703, GAP, HTPB, PEG, and F2314) were constructed. Molecular dynamics (MD) method was employed to investigate their binding energies (Ebind), compatibility, safety, mechanical properties, and energetic properties. The information and rules were reported for choosing better binders and guiding formula- tion design of high energy density material (HEDM). According to the calculated binding energies, the ordering of compatibility and stability of the five PBXs was predicted as ε-CL-20/PEG > ε-CL-20/ Estane5703 ≈ε-CL-20/GAP > ε-CL-20/HTPB > ε-CL-20/F2314. By pair correlation function g(r) analyses, hydrogen bonds and vdw are found to be the main interactions between the two components. The elasticity and isotropy of PBXs based ε-CL-20 can be obviously improved more than pure ε-CL-20 crystal. It is not by changing the molecular structures of ε-CL-20 for each binder to affect the sensitivity. The safety and energetic properties of these PBXs are mainly influenced by the thermal capability (C°p) and density (ρ) of binders, respectively. 相似文献
5.
安全质量费用工期在网络计划中的系统优化研究 总被引:1,自引:0,他引:1
施工网络计划中安全、质量、费用、工期达到综合优化是工程管理决策追求的目标,在工程项目管理中对这4个指标进行全面系统分析,并且进行综合均衡优化,对于提高工程项目的综合效益至关重要.采取在网络计划所有可行的施工方案中寻求最优的方案组合,从而达到总目标的优化.并且通过一个实例来说明本方法的应用. 相似文献
6.
A wide variety of liquid streams are generated as
part of the process research and development effort. Frequently these streams
are drummed off, either as intermediates that must be held for processing
or as wastes that must be sent off-site for disposal. Because of the long
times and low concentrations often involved, current thermoanalytical techniques
were inadequate to detect the potential of streams to generate gas. A custom-made
apparatus, the gas evolution test cell (GETC), was developed in the Merck
Research Laboratories to measure the gas generation potential of various streams
under precisely defined conditions, is the key innovation for the development
of a quantitative gas-generation test method. 相似文献
7.
为研究四川省重点河段水环境的安全性,利用综合评价指数法和模糊综合评价决策的数学模型对主要水系干流和支流河段的水质安全性做出了评价.结果显示,岷江流域的水质安全性较差,主要的污染物为重金属汞和铁,沱江和涪江流域的水质安全性较好. 相似文献
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现有药品质量安全监管的相关研究多从理性假设出发探讨政府与企业的互动机理,鲜有考虑企业质量安全意识的有限理性,导致模型对现实的解释能力不足。运用前景理论,通过价值函数和权重函数构建演化博弈的收益前景矩阵,研究了政府和药品生产企业的博弈过程,得到了影响企业质量安全意识的约束条件及因素。同时,研究了上市许可持有人质量激励、惩罚机制对药品生产企业质量安全意识的影响。研究结果表明:过度自信、风险偏好等是影响企业质量安全意识的重要因素;上市许可持有人的质量激励与惩罚能否发挥作用取决于企业的风险态度;在质量激励、惩罚条件下,上市许可持有人需加大监督或惩罚力度来改善企业的质量安全意识。 相似文献
9.
我国的生活饮用水行业中,目前常使用的管材分为金属类管材和非金属类管材两种。由于金属类管材本身的化学特性,行业内必须在此类管材的内壁上进行防腐处理,通常采用一些高分子防腐涂料。可用于给水行业的涂料品种繁多,涂料质量好坏直接影响到水质。我们针对一些常用产品作了浸泡试验,用吹扫捕集-GC-MS方法对水中溶出的可挥发性有机物进行了检测,发现一些产品在水中溶出了大量的甲苯、乙苯、二甲苯、甲乙苯等苯系物,且浸泡30d后仍有溶出物。这些物质长期存在会导致人体中枢神经系统紊乱,严重危害人体健康。行业内关于水源水中此类有机物污染的监测比较充分,而对于防护涂料可能污染水质的状况并未引起足够重视。 相似文献
10.
D. Joe Boone 《Accreditation and quality assurance》2004,10(1-2):5-9
A recent US Institute of Medicine report indicated that up to 98,000 deaths and more than 1 million injuries occur each year in the United States due to medical errors. These include diagnostic errors, such as an error or delay in diagnosis, failure to employ indicated tests and the use of outmoded tests. Laboratory tests provide up to 80% of the information used by physicians to make important medical decisions, therefore it is important to determine how often laboratory testing mistakes occur, whether they cause patient harm, where they are most likely to occur in the testing process, and how to prevent them from occurring. A review of the literature and a US Quality Institute Conference in 2003 indicates that errors in laboratory medicine occur most often in the pre-analytical and post-analytical steps in the testing process, but most of the quality improvement efforts focus on improving the analytical process. Measures must be developed and employed to reduce the potential for mistakes in laboratory medicine, including better indicators for the quality of laboratory service. Users of laboratory services must be linked with the laboratorys information system to assist them with decisions about test ordering, patient preparation, and test interpretation. Quality assessment efforts need to be expanded beyond external quality assessment programs to encompass the detection of non-analytical mistakes and improving communication between the users of and providers of laboratory services. The actual number of mistakes in laboratory testing is not fully recognized, because no widespread process is in place to either determine how often mistakes occur or to systematically eliminate sources of error. We also tend to focus on mistakes that result in adverse events, not the near misses that cause no observable harm. The users of laboratory services must become aware of where testing mistakes can occur and actively participate in designing processes to prevent mistakes. Most importantly, healthcare institutions need to adopt a culture of safety, which is implemented at all levels of the organization. This includes establishing closer links between providers of laboratory services and others in the healthcare delivery system. This was the theme of a 2003 Quality Institute Conference aimed at making the laboratory a key partner in patient safety. Plans to create a permanent public–private partnership, called the Institute for Quality in Laboratory Medicine, whose mission is to promote improvements in the use of laboratory tests and laboratory services are underway.Presented at the 9th Conference on Quality in the Spotlight, 18–19 March 2004, Antwerp, Belgium. 相似文献