首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   51篇
  免费   3篇
  国内免费   34篇
安全科学   2篇
废物处理   1篇
环保管理   22篇
综合类   39篇
基础理论   15篇
污染及防治   3篇
评价与监测   2篇
社会与环境   2篇
灾害及防治   2篇
  2024年   2篇
  2023年   3篇
  2022年   5篇
  2021年   8篇
  2020年   5篇
  2019年   9篇
  2018年   2篇
  2017年   4篇
  2016年   1篇
  2015年   3篇
  2014年   3篇
  2013年   4篇
  2012年   4篇
  2011年   4篇
  2010年   1篇
  2008年   2篇
  2007年   1篇
  2006年   4篇
  2004年   3篇
  2003年   1篇
  2002年   1篇
  2001年   1篇
  2000年   1篇
  1999年   3篇
  1998年   1篇
  1996年   2篇
  1995年   1篇
  1993年   1篇
  1992年   1篇
  1986年   1篇
  1984年   1篇
  1974年   2篇
  1971年   3篇
排序方式: 共有88条查询结果,搜索用时 31 毫秒
31.
The ranking of air quality control measures according to a number of evaluation criteria and with the participation of a large number of interested publics is demonstrated. A pilot study for the South Coast Air Quality Management District of California serves as the reference point. Several methodological considerations are addressed, such as: (a) the enhancement of criterion priorities to account for the variability among the performance of the control measures when incommensurable impact levels are applied: (b) the derivation of alternative rankings according to the priorities of potential coalitions; (c) the assessment of the potential acceptability of a collective ranking given the degree of solidarity among participants with similar interest affiliations; and (b) the assessment of the extent to which the performance of specific control measures may override priority differences and lead to insignificant ranking differences.  相似文献   
32.
The Monarch butterfly reserve in west-central Mexico attracts more than 250 000 visitors during the four-month annual overwintering period and yet the project has been unable to generate an impetus for local development among the indigenous and peasant communities in the region. This chapter explores the reasons for this failure and evaluates a proposed alternative development strategy. In addition to the usual problems of the paucity of local linkages, the problems involved with property rights and participation in decision-making and management suggest the need to reevaluate the model for successful and sustainable tourist development. An alternative model is presented that might contribute to overcoming the obstacles.  相似文献   
33.
针对自然保护区公路路线方案选择中存在的盲目性、片面性和主观性问题,本文以环长白山旅游公路建设项目环境影响评价方案为例,提出运用层次分析法进行路线方案比选。结果表明,在公路环境影响评价的路线方案选择过程中,层次分析法是一种较好的定量分析方法。  相似文献   
34.
奥运湖不同补水方案营养状态趋势分析   总被引:1,自引:0,他引:1  
规划中的奥运湖位于奥林匹克公园,运行中将采用人工补水方式。为保证未来奥运湖的正常景观生态功能,源水经奥运公园中人工湿地处理后再引入湖中。在规划设计阶段,提出三种补水方案:(1)清河再生水厂出水经湿地处理后入湖,(2)清河河水经湿地处理后入湖,(3)经湿地处理达地表水环境标准中的Ⅳ类水要求后入湖。为了考察不同水源补水方案对奥运湖的水质保障程度,本研究对不同方案下奥运公园湖水质的时间、空间变化过程予以模拟,分析评价奥运湖可能出现的富营养化状况,并对各个补水方案带来的富营养化风险和基本成因予以推断,为奥运湖的设计运行提供技术依据。结果表明,方案3的富营养化风险最小、水质保障程度最高。结合三种补水方案水质特点,推断磷是主要限制因子,所以控制磷的浓度是保证水质安全、降低富营养化风险的重要途径。  相似文献   
35.
Integrated solutions are needed for sustainable management of risks posed by recreational boats to coastal water quality and ecosystems. Fouling organisms roughen vessel hull surfaces, creating friction that slows sailboats and increases fuel consumption by powerboats. Hull fouling control strategies for recreational boats that are stored in the water may include antifouling hull paints, newer alternative hull coatings, periodic in-water hull cleaning, and excluding propagules by surrounding the boat with a slip liner or raising it above water on a lift. Copper discharged to harbor waters from antifouling paints via passive leaching and in-water hull cleaning may elevate dissolved copper levels above government standards. Invasive species carried among boat-hull fouling organisms may be introduced as boats move among coastal areas. Some of these species tolerate copper in antifouling paints and copper-polluted harbor waters. Policy development must consider supply-side capacity, as well as economic and environmental sustainability, in managing these issues. This paper presents a supply-side evaluation useful in developing policies to co-manage water quality and invasive species risks for recreational boats navigating along the coasts of California, the Baja California peninsula and California's Sacramento-San Joaquin Delta. Supply-side perspectives on services, materials, costs, and boat owner behaviors, such as residence and travel patterns, awareness of hull-coating choices and selection of hull coatings, are determined. Analyses include evaluation of risks, risk management capacity and costs, and role of education in risk management. The issues raised are broadly applicable, as they are appearing on research and policy agendas in diverse coastal areas.  相似文献   
36.
氯氟烃替代物的开发研究进展   总被引:3,自引:0,他引:3  
重点介绍了近年来国内外对氯氟烃替代物的研究开发动向,并简要地介绍了主要替代物的性能及应用情况。  相似文献   
37.
This article presents a historical analysis of the power generation choices in Zimbabwe since independence in 1980; their causes and consequences. In the early 1980s, the electricity supply choices of the country were dictated by a policy of self-sufficiency, and least-cost supply options (e.g. imports and hydropower) were rejected at a not negligible economic cost. At the end of the 1980s, a new political environment and pressures from the World Bank prompted substantial changes towards least-cost alternatives. In the early 1990s, security of supply motives still played an important role and financial constraints were severe. At present, however, there is little evidence that imported power is still as cheap a source of electricity as it was about 15 years ago. This situation together with the ongoing trend towards higher discount rates imply that thermal power, in particular coal-fired power, will dominate future electricity supply investments in Zimbabwe.  相似文献   
38.
It is estimated that some 17 metric tons of residual oxidants (chlorine) are discharged into the enclosed coastal seawater of Kuwait on a daily basis from power-desalination plants alone. Alarmed by the unlimited number of reported cases of damage to marine aquatic systems due to chlorine discharge around the world, several alternatives were proposed to control such a massive discharge of residual oxidant into seawaters. Most of the proposed alternatives lacked the basic criteria necessary for their evaluation, justification, and then selection. The objective of this article is to provide a conceptual approach that can be used to select a control measure for residual oxidant discharge in Kuwait coastal seawaters. This approach is based on state-of-the-art knowledge and the unique operational and environmental factors involved. A matrix system was designed whereby the cost of residual chlorine control alternative, its effectiveness, and environmental and public health impact, performance, and reliability in Kuwait can be compared and evaluated. The selection approach considered currently operating power plants in terms of their engineering design and material (cast iron or steel condensers), current operational conditions, operator's perception, acceptability, and projected problems associated with the environmental management of proposed modifications. The proposed approach revealed that in Kuwait, conventinal chlorination was marginally superseded only by chlorination/dechlorination using SO2 and operation alteration using process optimization. The overall cost-effective assessment matrix classified other alternatives as worse than chlorination by various degrees. Ozone and UV were found to be the worst and the least desirable alternatives for biofouling control of seawater in Kuwait. In light of the available information on the consequences of the Gulf War on the marine environment, and the potential formation of additional halogenated organic compounds through the reaction of residual chlorine with the released petroleum hydrocarbons, it is essential to control residual chlorine discharged into the nearshore environment of Kuwait.  相似文献   
39.
本文选择了紫背浮萍、四尾栅藻、蚤状溞和稀有鮈鲫4种本土水生生物,开展了阳离子表面活性剂、织物三防整理剂、C4三防整理剂和C6三防整理剂4种全氟辛烷磺酸盐(PFOS)替代品的安全性评估,为筛选理想PFOS化学替代品提供科学依据。急性毒性结果发现阳离子表面活性剂对4种水生生物均未显示出急性毒性;织物三防整理剂、C4三防整理剂和C6三防整理剂对蚤状溞的LC50值分别为17.97、64.61和85.58 mg·L-1,显示出低的急性毒性。另外,织物三防整理剂对四尾栅藻的半数抑制浓度(EC50)值为88.32 mg·L-1,而对稀有鮈鲫半致死浓度(LC50)值为14.79 mg·L-1,均存在急性毒性。短期生长抑制试验结果发现阳离子表面活性剂、织物三防整理剂、C4三防整理剂和C6三防整理剂对稀有鮈鲫生长抑制最低可见效应浓度(LOEC)值分别为20、1.5、100和50 mg·L-1,表明4种PFOS替代品均显示低慢性毒性。急慢性综合分析可知C4和C6三防整理剂相对较安全,可能成为理想的PFOS替代品。  相似文献   
40.
鉴于作为评价对象的城市社会经济环境复合系统具有多目标、多要素、动态关联等突出的系统动力学特征,选择和应用系统动力学方法开展城市发展规划环评在理论上具有可行性和技术优势.作为典型资源型城市的山西省临汾市正面临转变发展方式和加快环境治理的紧迫要求,本文依托该市转型发展规划环评工作,在全面识别和剖析城市发展要素、现状问题及其成因基础上,以经济发展、产业结构、节能减排和环境改善为重点研究了规划要素间的动态反馈关系,以此构建城市转型发展规划环评SD模型,并对4个规划替代方案进行模拟和评价.结果显示,在环境目标刚性约束下所有替代方案均不能实现人均GDP翻番的较高经济增长目标,其中以较强环境约束为特征的“方案III”具有最好的环境与经济综合效果.据此评价建议临汾市应在确保实现环境改善目标的前提下主动放缓工业增长速度,同时加快以“煤焦铁电”为代表的主导产业结构调整并继续加大节能减排力度,全面提高城市可持续发展能力.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号