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   119篇
  免费   1篇
  国内免费   4篇
安全科学   12篇
废物处理   2篇
环保管理   33篇
综合类   61篇
基础理论   6篇
污染及防治   7篇
社会与环境   2篇
灾害及防治   1篇
  2021年   2篇
  2020年   1篇
  2019年   1篇
  2018年   1篇
  2017年   8篇
  2016年   3篇
  2015年   5篇
  2014年   8篇
  2013年   11篇
  2012年   4篇
  2011年   8篇
  2010年   6篇
  2009年   9篇
  2008年   5篇
  2007年   4篇
  2006年   6篇
  2005年   1篇
  2004年   8篇
  2003年   2篇
  2002年   2篇
  2001年   3篇
  2000年   5篇
  1999年   1篇
  1998年   3篇
  1997年   1篇
  1996年   1篇
  1995年   3篇
  1994年   3篇
  1993年   4篇
  1992年   2篇
  1991年   1篇
  1985年   1篇
  1981年   1篇
排序方式: 共有124条查询结果,搜索用时 156 毫秒
61.
电除尘振打结构形式对除尘器除尘效率有较大的影响 ,通过对机械旋围挠臂振打和电磁振打的运行分析 ,认为顶部电磁锤振打有较好的清灰效果和合理的结构及布置  相似文献   
62.
Environmentally sound manufacture does not have its source only in developing and improving the techniques for treating solid, liquid and gaseous wastes at the end of the production process. Our experience shows that more effort and capital budgets must be devoted to developing preventive measures. Although the treatment techniques have become very advanced and meet ecological requirements to a very high degree, they are now reaching the limits of their technological and economic feasibility. Environmental protection at the production site has undergone structural change in recent years. The emphasis has shifted to preventive techniques which affect the production process itself, avoiding the emergence of waste at the “end of the pipe” by preventing its formation or recycling it straight away. This integrated approach is in harmony with the demands of sustainable production. The functions of in-process environmental protection measures need to be looked at as a whole from the points of view of both environmental protection and cost-effectiveness. Some integrated methods are described.  相似文献   
63.
以水作溶剂、过氧化物作引发剂合成马来酸酐与丙烯酸共聚物,详细探讨了共聚物组成、引发剂浓度、反应温度和时间等因素对共聚物稳定分散Ca(OH)2碱性悬浮液吸收SO2废气的影响.结果表明,该生物降解性无磷、无氮型水质稳定剂对碱液吸收SO2的效率可提高50%以上.  相似文献   
64.
Land taken by artificial surfaces has an impact on the quality of life and ecosystems. To reduce possible negative impacts of land take, the European Commission proposed setting a milestone objective for 2020 in terms of future rates of land take.

This paper describes a methodology to model the impacts of the 2020 land-take milestone proposed in the RERM in the European Union 27 MS. An integrated modelling framework was configured to assess the spatial impact of two land-take scenarios: a ‘Reference’ scenario, which is driven by demographic and economic trends, and a ‘Target 0’ scenario that follows the 2020 land-take milestone proposed in the RERM. We conclude that the implementation of the 2020 land-take milestone, by reducing future land take in Europe, will foster more efficient use of land (less land taken for the same activity levels) and minimise negative impacts on non-artificial land uses.  相似文献   

65.
This study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan. Industrial wastewater samples were collected from the in-let, out-let and all cells of the constructed wetland (CW) and analyzed for heavy metals such as lead (Pb), cadmium (Cd), iron (Fe), nickel (Ni), chromium (Cr) and copper (Cu) using standard methods. Similarly, samples of aquatic macrophytes and sediments were also analyzed for selected heavy metals. Results indicate that the removal efficiencies of the CW for Pb, Cd, Fe, Ni, Cr, and Cu were 50%, 91.9%, 74.1%, 40.9%, 89%, and 48.3%, respectively. Furthermore, the performance of the CW was efficient enough to remove the heavy metals, particularly Cd, Fe, and Cu, from the industrial wastewater fed to it. However, it is suggested that the metal removal efficiency of the CW can be further enhanced by using proper management of vegetation and area expansion of the present CW.  相似文献   
66.
Amory B. Lovins 《Ambio》2010,39(3):236-248
Protecting the climate is not costly but profitable (even if avoided climate change is worth zero), mainly because saving fuel costs less than buying fuel. The two biggest opportunities, both sufficiently fast, are oil and electricity. The US, for example, can eliminate its oil use by the 2040s at an average cost of 15 per barrel (200015 per barrel (2000), half by redoubled efficiency and half by alternative supplies, and can save three-fourths of its electricity more cheaply than operating a thermal power station. Integrative design permits this by making big energy savings cheaper than small ones, turning traditionally assumed diminishing returns into empirically observed expanding returns. Such efficiency choices accelerate climate-safe, inexhaustible, and resilient energy supply—notably the “micropower” now delivering about a sixth of the world’s electricity and 90% of its new electricity. These cheap, fast, market-financeable, globally applicable options offer the most effective, yet most underestimated and overlooked, solutions for climate, proliferation, and poverty.  相似文献   
67.
This study investigates the effect of environmental investment and related spillover effects on productivity in the agricultural sector by using a panel data of horticultural firms in Andalusia (Southern Spain). The results indicate a positive relationship between firm investment in environmental practices and productivity improvement, also showing the presence of positive environmental spillovers. In a second-stage of analysis, the incidence of environmental factors in firm specific individual technical efficiency is estimated. This analysis also shows the link between environmental knowledge diffusion and horticultural firms' performance.  相似文献   
68.
采用化学沉淀法对模拟含铜废水进行处理,分别考察了反应pH值、温度、沉淀时间、絮凝剂(PAM)用量以及PAM作用下沉淀时间等因素对模拟含铜废水处理的影响,并在最佳条件下对实际含铜废水进行了处理研究。结果表明,采用化学沉淀法处理200 mg/L的模拟含铜废水时,1‰聚丙烯酰胺(PAM)的最佳加入比例为30 mg/L,在25℃下,合适的pH值为7.12左右,沉淀时间13 min。在此条件下对来自葫芦岛锌厂的酸性平均含铜为167 mg/L的实际废水继续处理,处理后废水中铜离子浓度平均值为0.87 mg/L,可以实现实际废水中铜离子的有效去除。  相似文献   
69.
提高能效是减排的重要途径,荷兰长期能效协议和能效标杆合约在这方面取得了很大成效,其成功经验值得研究和学习。本文首先系统介绍了荷兰长期能效协议和能效标杆合约的构建、实施及监督过程,分析了其取得的成效和存在的不足。然后描述了自愿协议式方法在中国的应用情况和我国面临的节能减排压力。最后总结出长期能效协议和能效标杆合约对我国应用和推广自愿协议式方法的启示。  相似文献   
70.
针对我国日益凸显的水资源过度开发、水环境污染、水资源短缺、用水效率与效益低下等水危机,对我国近年来出台最严格水资源管理制度、"水污染防治行动计划"(称"水十条")等水资源管理、水环境保护相关政策与研究进展及国外在水环境管理方面经验进行了探讨。分析了"水十条"实施后在水资源管理、水生态安全、法律法规与执法监管、资金投入与激励机制、技术推进与公众参与等需解决的关键问题与推进重点工作,提出具体措施包括以协作机制优化区域流域水环境管理,完善水权交易并规范绿色投融资体系,创新水文化建设与公众参与模式,优化分区、分级、共治的水环境管理法规与执法支撑体系,强化信息化、集成化的水环境管理与应用等。  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