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971.
高斯扩散衍生公式在环境风险评价中的应用   总被引:6,自引:0,他引:6  
为在大气环境风险评价中客观地确定危险源、估算各类突发性事故的危害,在高斯扩散模型基础上,通过严格的数学推导,得出一整套适用于鉴别与评估大气环境突发事故危害后果(危害区、危害期等)的定量估算公式,使用方便,结果精确。所有公式使用条件与高斯扩散模型相同,可用于直接求取任意浓度等值线精确的时、空位置及其特征点位置。作为高斯扩散模型的衍生公式,可广泛应用于风险工程设计、风险工程保险、环境风险评价、环境风险管理、环境影响评价与环境规划等各个领域  相似文献   
972.
石化行业是挥发性有机物(VOCs)的重要来源之一,然而,当前石化行业VOCs研究多集中于炼油厂VOCs排放特征分析,针对有机化工和合成材料等子行业的研究较为缺乏.选取珠三角地区某石化园区中石油炼制、合成材料和有机化工3个主要行业的8家代表性企业和园区周围敏感点为研究对象,采集分析了包含22种含氧VOCs(OVOCs)在...  相似文献   
973.
Environmental safety data are presented for [S,S]-Ethylene Diamine Disuccinate ([S,S]EDDS), a new, biodegradable, strong transition metal chelator. An environmental risk assessment for its use in detergent applications, which takes into account the chelating properties of [S,S]-EDDS, is proposed.

A property of [S,S]-EDDS that distinguishes it from other strong transition metal chelators is its, “ready” and transparent (no recalcitrant metabolites) biodegradation profile. Because its sorption to activated sludge solids is low ( Kp of 40 1/kg), removal of [S,S]EDDS during sewage treatment, which is greater than 96% as determined by the Continuous Activated Sludge test , is mainly ascribed to biodegradation. At projected use volumes in detergent applications [S,S] - EDDS predicted steady-state concentration in rivers leaving the mixing zone will be below 5 pg/I due to rapid biodegradation. [S,S]-EDDS exhibits low toxicity to fish and Daphnia ( both EC50s> 1000 mg/l). By contrast, due to limitation of the algal test for chelators apparent toxicity was observed (EC50 = 0.290 mg/l, NOEC - No observable Effect Concentration = 0.125 mg/l). Schowanek et al. [1] demonstrated that this is not toxicity sensu stricto but a chelation effect of trace metals in the test medium and of resulting essential nutrients limitation. This requires specific attention when the results of algal toxicity are to be extrapolated to a field situation to perform realistic risk assessment. Metal speciation calculations, using MINEQL+, show that at the predicted environmental concentrations of [S,S] - EDDS (1–5 μg/l), such a chelation effect would be insignificant. These calculations allow to estimate the NOEC for chelation effects in the field to be in the range of 0.250-0.500 mg/l, depending on the background water chemistry. These values are well above the laboratory NOEC.

An environmental risk assessment was performed using the EUSES (1.0) program. EUSES is currently the EU recommended tool for conducting risk assessments (TGD 1995). It was applied to estimate the river water and soil concentrations from production, formulation and private use life stages. The estimated PEC/PNEC ratio in all relevant environmental compartments is smaller than 1, indicating “no immediate concern” at the anticipated usage level.  相似文献   

974.
A qualitative study of employers' and employees' meanings of occupational health and safety (OHS) risk control was conducted among a sample of small businesses engaged in the Australian construction industry. Two OHS risks relevant to the construction industry were selected for study. One risk (falls from height) represented an immediate consequence, whereas the other (occupational skin disease) represented a long-term health effect. Meanings of the sources and control for these risks were explored during in-depth interviews. Participants perceived the immediate effect, falls from height OHS risk, as being more important in their workplaces than the delayed effect, skin disease OHS risk. The risk of falls from height was perceived to be controllable but requiring a great deal of effort to prevent, whereas there was a fatalistic resignation to the risk of occupational skin disease. Meanings of risk control for both occupational skin disease and falls from height focused on individual rather than technological risk controls. Organizational barriers to the adoption of technological OHS risk controls in the construction industry were identified.  相似文献   
975.
The Safety Element Method (SEM) is a method for improvements of safety results and safety approaches in the Norwegian mining industry. The method is developed by users and researchers in co-operation. The main approach of the method is that a group of organisational members assesses the current and desired situation for their own organisation within defined areas. Based on this assessment they work out a strategy and action plan to reach the internal goals for desired achievement, i.e. the desired situation defined. This article presents the implementation of the method in four mining companies and evaluates the method for its construct validity, criterion validity, face validity, how the method functions and is accepted among the users. The results show that the opinions regarding the experiences with the method are, on the whole, positive. The method is regarded as a valuable approach towards safety improvements. Subjective assessments play a prominent role in SEM, but these assessments are supported by an extensive review of empirical data such as accident reports, interview results and a questionnaire. This means that the internal assessments correspond well to the safety results of the companies and also to the independent external reviews carried out by the researcher.  相似文献   
976.
粉碎研磨设备粉尘爆炸的预防   总被引:1,自引:0,他引:1  
粉碎研磨设备火灾爆炸事故发生率较高。针对该过程的火险特点,防火对策应从防止粉尘沉积,消除粉尘源,防止摩擦、撞击、生热,消除静电危害,搞好工艺防火,惰性介质保护,设置防爆泄压装置,粉尘爆炸的抑制,火灾事故处理措施,加强消防安全教育诸方面加以考虑。  相似文献   
977.
煤矿危险源分类分级与预警   总被引:14,自引:0,他引:14  
关于危险源概念目前尚无准确的理论界定,为此,笔者试图阐明危险源分为固有型危险源和触发型危险源的新观点,提出并说明了对不同类型危险源应采用的不同的辩识与分级方法。在此基础上,结合企业实际,提出了危险源预警思想和模块设计方法。所有这些,对完善安全管理理论,提高煤矿安全管理水平具有理论意义和实用价值  相似文献   
978.
静电喷漆工艺应用普及很快,但其生产过程的火灾危险性属甲类。其火灾危险主要在于使用的漆料或有机溶剂,喷漆作业中存在电火花、静电火花、高温热表面、自然发热等引火源。为防止火灾爆炸发生,要注重防火防爆安全管理和强化必要的安全技术措施。  相似文献   
979.
一种现代化的安全管理方法──安全管理信息系统   总被引:13,自引:5,他引:8  
安全管理信息系统是现代化安全管理中,安全信息综合处理的枢纽,是安全信息管理、安全决策的关键。通过建立以安技部门为信息处理中心、各危险岗位和各专业部门为终端的安全管理信息系统网络,从而由安全信息反馈来推进对隐患的不断检查、整改和监控,形成闭环管理,力求把安全管理从传统的事后追踪变为事前的预防控制,使安全管理工作逐步走向科学化、系统化和规范化,对提高目前安全管理水平具有实际意义。  相似文献   
980.
基于景观结构的区域生态风险分析   总被引:76,自引:0,他引:76       下载免费PDF全文
以深圳市龙华镇为中心的324km2正方形区域为例,以1988~1996年期间的5幅景观遥感解译图为基本信息源,根据不同时段景观元素的结构特征,构造一个综合性生态风险指数,利用系统空间采样方法对生态风险指数进行变量空间化.通过对生态风险指数采样结果进行半变异函数分析和空间插值,可以解释生态风险的空间特征和内在形成机制.结果表明,1988~1996年,工作区内的生态风险强度不断增加,区域分布的不均匀性增大;南北方向为景观人为改造活动的主方向;沿梅澜和石龙两条高速公路沿线形成两条带状高生态风险区域,其中龙华镇中心及周围地区是急需采取保护性措施的重点区域.  相似文献   
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