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991.
建立了一种高效液相色谱-串联质谱法(LC-MS/MS)同时测定环境水样中8种有机磷农药的分析方法。以地表水、地下水、污水和废水样品作为代表性水样基底,前处理方法仅采用简单的滤膜过滤,在C18柱分离后,在多反应监测模式下进行分析检测。结果表明,敌百虫、毒死蜱等有机磷农药在样品保存过程中迅速发生降解,分析须在样本采集后1 d内完成;该方法的检出限为0.10~0.20 μg/L,线性拟合相关系数(r)均>0.995;不同基底、不同浓度的加标回收实验表明,8种有机磷农药在环境基底中的回收率为74.5%~118%,相对标准偏差为0.4%~8.6%。该方法操作简便、灵敏度高、准确性好,在未来环境监测工作中具有较好的应用前景。  相似文献   
992.
Using Japanese facility-level data from an OECD survey, we estimate the effects of implementation of ISO14001 and publication of environmental reports on the facilities’ environmental performance. While most previous studies focused on an index of emissions toxicity, this study examines three areas of impacts, none of which have been explored in the literature: natural resource use, solid waste generation, and wastewater effluent. The study is also unique in that the effectiveness of ISO14001 is considered in relation to environmental regulations. Our findings are summarized as follows. First, both ISO14001 and report publication help reduce all three impacts; the former appears more effective in all areas except wastewater. Second, environmental regulations do not weaken the effect of ISO14001. Third, assistance programs offered by local governments—a voluntary approach—promote facilities’ adoption of ISO14001. These findings suggest that governments can use command-and-control and voluntary approaches concurrently.  相似文献   
993.
In modern environmental risk analysis, inferences are often desired on those low dose levels at which a fixed benchmark risk is achieved. In this paper, we study the use of confidence limits on parameters from a simple one-stage model of risk historically popular in benchmark analysis with quantal data. Based on these confidence bounds, we present methods for deriving upper confidence limits on extra risk and lower bounds on the benchmark dose. The methods are seen to extend automatically to the case where simultaneous inferences are desired at multiple doses. Monte Carlo evaluations explore characteristics of the parameter estimates and the confidence limits under this setting.
R. Webster WestEmail:
  相似文献   
994.
An important consideration in conservation and biodiversity planning is an appreciation of the condition or integrity of ecosystems. In this study, we have applied various machine learning methods to the problem of predicting the condition or quality of the remnant indigenous vegetation across an extensive area of south-eastern Australia—the state of Victoria. The field data were obtained using the ‘habitat hectares’ approach. This rapid assessment technique produces multiple scores that describe the condition of various attributes of the vegetation at a given site. Multiple sites were assessed and subsequently circumscribed with GIS and remote-sensed data.  相似文献   
995.
Investment subsidies are widely used to induce adoption of new technologies that can lower the (marginal) cost of reducing emissions. To economize on these subsidies, governments would like to distinguish between firms that need to receive a subsidy to adopt a new technology, and firms that would adopt that technology even without subsidies. We show that policies consisting of a menu of emission taxes and investment subsidies can potentially induce firms to self-select.  相似文献   
996.
This study presents an assessment of the potential impact of geological contamination of the environment on the health of the population in Spišsko-Gemerské rudohorie Mts. (SGR Mts.). The concentration levels of potentially toxic elements (mainly As, Cd, Cu, Hg, Pb, Sb, and Zn) were determined in soils, groundwater, surface water, and stream sediments as well as in the food chain (locally grown vegetables). A medical study included some 30 health indicators for all 98 municipalities of the study area. The As and Sb contents in human fluids and tissues were analyzed in one municipality identified to be at the highest risk. Based on element content, environmental and health risks were calculated for respective municipalities. Out of 98 municipalities 14 were characterized with extremely high environmental risk and 10 were characterized with very high carcinogenic risk from arsenic (groundwater). Extensive statistical analysis of geochemical data (element contents in soils, groundwater, surface water, and stream sediments) and health indicators was performed. Significant correlations between element contents in the geological environment and health indicators, mainly cancer and cardiovascular diseases, were identified. Biological monitoring has confirmed the transfer of elements from the geological environment to human fluids and tissues as well as to the local food chain.  相似文献   
997.
青山水库底泥磷释放与库区水体磷浓度的关系   总被引:5,自引:0,他引:5  
通过对青山水库底泥磷释放特性的实验结果分析,对照库区水体浓度监测的数据,确定了库区各测点底磷释放量与水体浓度之间的关系,进而为库区环境总量控制与各支流的分配计算提供了依据。同时也为防止水库的进一步富营养化,进而改善水质提供了新的思路。  相似文献   
998.
The Lagoon Olho d'Água in Pernambuco State, Northeast Brazil has received increasing environmental concern due to significant stress from pollution in the catchment. The existing environmental problems are the result of great pressure from a broad range of human activities, especially in the last 10 years. Serious pollution exists mainly from some industrial and urban activities, which increased intensively after the eighties. There is a strong social and economical pressure for housing and construction near the lagoon, due to the available land nearby beaches and estuarine zone, and recently by growing tourism activities. Uncontrolled land use by low-income communities and the pressure for construction by developers have led to landfilling and to deterioration of water quality in the lagoon catchment. Improvement of the environmental conditions in the catchment needs integrated measures. Guidelines and some specific actions involving several institutions have been established and refer to sanitation and urban infrastructure as the main priorities. A main target is the construction of low-cost sewage system with smaller and decentralised treatment plants.  相似文献   
999.
论舰船设备的湿热试验   总被引:1,自引:1,他引:0  
湿热环境是海军舰船设备所需承受的重要环境条件之一。论述了湿热试验目的、物理现象。针对海军舰船设备以往采用的几种湿热试验方法存在的严酷度差异,着重对GB2423-81《电工电子产品基本环境试验规程试验Db:交变湿热试验》、GIB150.9-86《军用设备环境试验方法湿热试验》、IB839-75《电工产品湿热试验》和《实船环境试验条件》的试验严酷度进行了验证比对并得出结论。  相似文献   
1000.
香港海沙资源的勘探开发与管理   总被引:1,自引:0,他引:1  
海沙开采已成为仅次于油气开采的世界第二重要海洋开采业。1980年代以来,香港政府投资1.7×108港元为寻找海岸围垦填料进行了一系列的海沙勘探活动,在1828km2香港水域发现22个地点海沙资源储量7.4×108m3,其中9个地点4.2×108m3储量因覆盖层较厚或污染严重或海区环境特别敏感等原因被暂时搁置。1990~2002年共开采海沙2.7×108m3,为形成2100hm2新土地的多项围垦工程提供了约一半的填料。基于地球物理勘探和钻探资料建立了香港海域第四纪层序和海沙产状地质模型,发现和证实了含气沉积物地震剖面的声波浑浊现象。香港政府对海沙资源进行统一勘探和统一管理,强调海沙开采的环境和生态影响评估,利用废弃的海床挖沙坑回填倾废的非污染海泥和受污染海泥。我国内地海沙勘探管理可以从中取得借鉴。  相似文献   
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