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71.
对地震保险体制改革的探索   总被引:1,自引:2,他引:1  
从研究地震灾害规律和保险经营特点之间的矛盾入手,叙述地震保险经营的困难,剖析我国现行地震保险体制的缺陷,提出了建立一个新的,相对科学和合理的地震保险体制的若干建议。  相似文献   
72.
伴随着经济的繁荣和人民物质生活质量的提高,餐饮业日益繁荣起来,再结合中国素来"民以食为天",传统饮食文化的特殊性及复杂性,导致烹饪过程复杂,同时也带来了各种各样的油烟污染问题。油烟已经成为继噪声、尾气、沙尘之后的又一大污染问题,并且成为百姓环保投诉的热点问题之一。《饮食业油烟排放标准》(GB18483-2001)是目前我国环保行业监测饮食业油烟的唯一标准方法,在实际工作中存在一定的局限性和不完备性,对现行标准进行修订势在必行。  相似文献   
73.
CFD-based simulation of dense gas dispersion in presence of obstacles   总被引:1,自引:0,他引:1  
Quantification of spatial and temporal concentration profiles of vapor clouds resulting from accidental loss of containment of toxic and/or flammable substances is of great importance as correct prediction of spatial and temporal profiles can not only help in designing mitigation/prevention equipment such as gas detection alarms and shutdown procedures but also help decide on modifications that may help prevent any escalation of the event.The most commonly used models - SLAB (Ermak, 1990), HEGADAS (Colenbrander, 1980), DEGADIS (Spicer & Havens, 1989), HGSYSTEM (Witlox & McFarlane, 1994), PHAST (DNV, 2007), ALOHA (EPA & NOAA, 2007), SCIPUFF (Sykes, Parker, Henn, & Chowdhury, 2007), TRACE (SAFER Systems, 2009), etc. - for simulation of dense gas dispersion consider the dispersion over a flat featureless plain and are unable to consider the effect of presence of obstacles in the path of dispersing medium. In this context, computational fluid dynamics (CFD) has been recognized as a potent tool for realistic estimation of consequence of accidental loss of containment because of its ability to take into account the effect of complex terrain and obstacles present in the path of dispersing fluid.The key to a successful application of CFD in dispersion simulation lies in the accuracy with which the effect of turbulence generated due to the presence of obstacles is assessed. Hence a correct choice of the most appropriate turbulence model is crucial to a successful implementation of CFD in the modeling and simulation of dispersion of toxic and/or flammable substances.In this paper an attempt has been made to employ CFD in the assessment of heavy gas dispersion in presence of obstacles. For this purpose several turbulence models were studied for simulating the experiments conducted earlier by Health and Safety Executive, (HSE) U.K. at Thorney Island, USA (Lees, 2005). From the various experiments done at that time, the findings of Trial 26 have been used by us to see which turbulence model enables the best fit of the CFD simulation with the actual findings. It is found that the realizable k-? model was the most apt and enabled the closest prediction of the actual findings in terms of spatial and temporal concentration profiles. It was also able to capture the phenomenon of gravity slumping associated with dense gas dispersion.  相似文献   
74.
以数学软件matlab内嵌的SimuLink工具箱为研究工具,结合国际水协( IWA)提出的活性污泥一号模型(ASM1)对欧盟科学技术合作计划(COST)提供的AO标准工艺流程建立数学模型并加以模拟,将模拟结果和COST提供的标准模拟结果进行比较,在各级反应器内的两者结果基本匹配,认为模型的建立、模拟结果合理可靠,基于该工艺模型的拓展模型和变型可进一步为实际工艺的设计与运行提供参考。  相似文献   
75.
硫化物在进行显色反应时,溶液中酸度的增高生成亚甲兰的产率也随之增加。国标法规定分析无色透明清洁水样时,不加20ml乙酸锌-乙酸钠溶液,这样分析的结果不正确。正确的方法应与绘制标准曲线的操作步骤完全一样,需加20ml乙酸锌-乙酸钠溶液。  相似文献   
76.
介绍了原子吸收光度法中的光谱干扰和非光谱干扰,指出标准加入法和分析校准曲线法是消除和减少某些干扰最简单、快速的校准方法。在标准加入法中,当分析曲线呈线性时,表明分析结果可信,当分析曲线不呈线性,表明方法灵敏度随质量浓度变化而变化,分析结果的准确性有问题。以改变基体的质量浓度和在同一质量浓度的基体溶液中加入不同量的标准两个实验可以验证标准加入法在原子吸收光度法中的适用性。  相似文献   
77.
环境噪声标准体系设计与相互关系研究   总被引:1,自引:0,他引:1  
针对当前突出的环境噪声问题,提出了噪声管理需要3个层次不同的标准,每种标准有适用的对象、制订依据、作用和特征,在介绍不同层次标准相互关系基础上提出标准制订和修订的建议.  相似文献   
78.
自然灾害脆弱性评价研究对于提高区域防灾减灾能力具有重要现实意义。以陕西省10市1区为例,选取6个子系统29项指标,运用均方差赋权法对陕西区域性自然灾害脆弱性进行评价研究。结果表明:自然条件、经济和基础设施3个子系统是影响陕西省区域性自然灾害脆弱性的主要因素;经济、社会和基础设施等因素是区域应灾能力的重要表现,直接影响着区域自然灾害脆弱性的高低;陕西省区域性自然灾害脆弱性具有显著的时空分布特征,关中平原及陕南秦巴山区各地级市、区自然灾害脆弱性高于陕北地区。  相似文献   
79.
Infrastructure development is a major driver of biodiversity loss globally. With upward of US$2.5 trillion in annual investments in infrastructure, the financial sector indirectly drives this biodiversity loss. At the same time, biodiversity safeguards (project-level biodiversity impact mitigation requirements) of infrastructure financiers can help limit this damage. The coverage and harmonization of biodiversity safeguards are important factors in their effectiveness and therefore warrant scrutiny. It is equally important to examine the extent to which these safeguards align with best-practice principles for biodiversity impact mitigation outlined in international policies, such as that of the International Union for Conservation of Nature. We assessed the biodiversity safeguards of public development banks and development finance institutions for coverage, harmonization, and alignment with best practice. We used Institute of New Structural Economics and Agence Française de Développement's global database to identify development banks that invest in high-biodiversity-footprint infrastructure and have over US$500 million in assets. Of the 155 banks, 42% (n = 65) had biodiversity safeguards. Of the existing safeguards, 86% (56 of 65) were harmonized with International Finance Corporation (IFC) Performance Standard 6 (PS6). The IFC PS6 (and by extension the 56 safeguard policies harmonized with it) had high alignment with international best practice in biodiversity impact mitigation, whereas the remaining 8 exhibited partial alignment, incorporating few principles that clarify the conditions for effective biodiversity offsetting. Given their dual role in setting benchmarks and leveraging private finance, infrastructure financiers in development finance need to adopt best-practice biodiversity safeguards if the tide of global biodiversity loss is to be stemmed. The IFC PS6, if strengthened, can act as a useful template for other financier safeguards. The high degree of harmonization among safeguards is promising, pointing to a potential for diffusion of practices.  相似文献   
80.
抗静电纺织品的测试标准浅析与探讨   总被引:1,自引:0,他引:1  
本文阐述了目前抗静电纺织品的发展现状和主流开发技术路线,结合常用的纺织品抗静电性能测试方法和技术,浅析了目前我国的抗静电纺织品检测标准和方法,探讨了一些技术细节和常见问题。  相似文献   
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