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611.
表面活性剂在环境保护中的应用   总被引:2,自引:0,他引:2  
表面活性剂是现代科学技术中的一种重要的精细化工品。它可以减少液体、固体和气体界面间的表面或界面张力,容易在水或其他液体中混合或扩散,因而广泛应用于环境保护等领域。本文介绍了表面活性剂在水污染处理技术、大气除尘技术、土壤和地下水污染修复技术中的应用现状,同时分析了表面活性剂在各种技术应用上的优点和缺点,对今后的应用研究提出了建议。  相似文献   
612.
固定化微生物技术在环境工程中的应用研究进展   总被引:13,自引:2,他引:11  
综述了固定化微生物的制作方法及载体的选择,并对固定化技术在废水、大气和土壤等环境工程中的应用和研究进展状况进行了简介,同时对固定化技术的应用前景及存在的问题进行了评述。  相似文献   
613.
用政策作指导以法律为依据提高环境评价质量   总被引:1,自引:0,他引:1  
谭祥炳 《四川环境》2000,19(2):73-75
本文提出了环境影响评价必须用政策作指导 ,以法律为依据 ,提高环境影响评价质量的几点意见。  相似文献   
614.
概述了FU型链式输送机的工作原理、性能以及在选用时应注意的原则,并介绍了在氧化铝熟料窑电除尘系统中的应用.  相似文献   
615.
With about half of its territory being farmed, agriculture is the main land use in the European Union (EU). As over 10% of the total EU manufacturing output comes from the agri-food sector, it also is an economic factor of great importance. Moreover, EU policy in this sector has far-reaching consequences ranging from the EU's status as a global trade partner to landscape preservation and development. The LUMOCAP Policy Support System is targeted towards policy makers in the European Commission (EC) and its Member States (MS) and aims to provide support in the field of sustainable agricultural and rural development. To this end it incorporates an integrated model with socio-economic and bio-physical processes, operating at different spatial scales. For supporting integrated assessment, a large number of policy levers is included as inputs for these models and outputs are transformed into policy-relevant social, economic and environmental indicators. The whole system is framed in a flexible, modular and easy to use software package that is useable for process experts and policy-analysts alike.This paper describes the integrated model, the individual models and a first calibration of the system. It demonstrates the system's behaviour for typical scenario runs and concludes with a reflection on the current status of the system and some recommendations for further development.  相似文献   
616.
树轮异常结构作为反映气候变化的一个重要参数,已被广大生态学家所重视并应用。树轮异常结构包括霜轮、浅轮、伪轮、畸形木材反应木、树脂道、火疤等。这些异常年轮结构与温度、降水、光照等气候因子有着复杂的相关关系。温度对年轮异常结构的影响主要表现在低温对形成层生长的抑制作用,从而形成霜轮、浅轮。生长期内干旱,形成层生长时间短,甚至使形成层生长减慢或停止,从而形成伪轮。高强度的光照会引起高温少雨,加剧旱情的发生,从而导致伪轮。另外,通过对树轮异常结构的分析,可用这些特征来重建森林干扰的历史,如火山喷发、火灾、冰灾、虫害、旱灾、地震等。这些研究在帮助人们了解和研究古气候变化对森林植被的影响,以及预测未来全球变化对陆地生态系统的影响有重要的理论和现实意义。文章综述了气候变化对树轮异常结构的影响的研究进展和应用,并概述了发展前景,希望能加快和拓宽这一领域的发展。  相似文献   
617.
This study explores the current implementation challenges of the Policy Environmental Assessment (PEA), including the implementation of a far richer, more diverse (at macro level), and better understanding of PEA and integration with decision making. The results contribute to the analysis of PEA through different hierarchies of assessment. Stemming from the theory and practice of policy, a concept of PEA hierarchies is proposed including the uppermost PEA, upper-lower PEA, and lowermost PEA. Afterward, the differences of the three hierarchies are interpreted, in terms of aims, principles, processes, and methods. The evaluation of the policy environmental impacts from different lens helps solve the complexities of policies and identify opportunities for improvement of PEA.  相似文献   
618.
HAZID方法浅析   总被引:3,自引:0,他引:3  
结合实际工程建设项目开展危险源辨识(HAZID)分析的情况,介绍了HAZID分析方法的广义和狭义概念内涵,主要分析步骤、每步主要工作内容、典型引导词、分析形式和特点,并将HA-ZID方法与常用的过程危险源方法、尤其是HAZOP分析方法进行了对比,以帮助读者更好地理解、运用此方法。本文拟推荐的HAZID分析方法将危险化学品行业的风险管理向前延伸到项目的早期阶段(如项目论证、可行性研究、基础工程设计或初步设计阶段),可以帮助项目组在项目建设早期认识与项目有关的健康、安全、环境(HSE)各方面问题的重要性和相关性,所辨识出的关键危险源及其危险,为下一步有重点、有目的地开展项目HSE风险管理确定了关注重点。在早期阶段进行HAZID分析,还可以有机会以最小的代价实现对项目厂址和总图布置的调整、工艺方案和设计原则的优化,可以避免后期再发现HSE隐患、必须整改时可能存在的不可实施性,或对项目费用、进度等产生严重负面影响。  相似文献   
619.
In the last decade, Indian shrimp aquaculture production tripled from 30,000 tons (1990) to 102,000 tons (1999). This fast development, combined with a lack of adequate planning and regulation, caused a number of environmental problems and social conflicts, including conversion of mangroves, water pollution, and salinization of drinking water wells. Because of the significant investments made in shrimp culture and the size of the environmental and social impacts, the formulation of a regulatory framework for shrimp aquaculture has been subject to an intensive debate between the aquaculture and the environmental lobbies. Following an order from the Supreme Court (1996), the Aquaculture Authority was established and a regulatory and institutional framework for the shrimp aquaculture sector has been set up. However, implementation of the system is still defective, and there is an urgent need for improvement. Farmers are increasingly able to prevent the devastating white spot disease in shrimps, and in the absence of proper planning and regulation, further expansion of shrimp production could result in significant additional environmental and social costs. The environmental and social management of Indian shrimp farming can be improved through a mix of policy measures, including strengthening of the license system, more effective enforcement of regulations, the use of economic incentives, and increased monitoring of environmental and social impacts.  相似文献   
620.
The success of buffer installation initiatives and programs to reduce nonpoint source pollution of streams on agricultural lands will depend the ability of local planners to locate and design buffers for specific circumstances with substantial and predictable results. Current predictive capabilities are inadequate, and major sources of uncertainty remain. An assessment of these uncertainties cautions that there is greater risk of overestimating buffer impact than underestimating it. Priorities for future research are proposed that will lead more quickly to major advances in predictive capabilities. Highest priority is given for work on the surface runoff filtration function, which is almost universally important to the amount of pollution reduction expected from buffer installation and for which there remain major sources of uncertainty for predicting level of impact. Foremost uncertainties surround the extent and consequences of runoff flow concentration and pollutant accumulation. Other buffer functions, including filtration of groundwater nitrate and stabilization of channel erosion sources of sediments, may be important in some regions. However, uncertainty surrounds our ability to identify and quantify the extent of site conditions where buffer installation can substantially reduce stream pollution in these ways. Deficiencies in predictive models reflect gaps in experimental information as well as technology to account for spatial heterogeneity of pollutant sources, pathways, and buffer capabilities across watersheds. Since completion of a comprehensive watershed-scale buffer model is probably far off, immediate needs call for simpler techniques to gage the probable impacts of buffer installation at local scales.  相似文献   
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