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   729篇
  免费   7篇
  国内免费   33篇
安全科学   9篇
废物处理   42篇
环保管理   41篇
综合类   55篇
基础理论   102篇
污染及防治   414篇
评价与监测   63篇
社会与环境   39篇
灾害及防治   4篇
  2023年   28篇
  2022年   152篇
  2021年   145篇
  2020年   47篇
  2019年   47篇
  2018年   41篇
  2017年   53篇
  2016年   43篇
  2015年   25篇
  2014年   37篇
  2013年   38篇
  2012年   22篇
  2011年   22篇
  2010年   8篇
  2009年   10篇
  2008年   11篇
  2007年   9篇
  2006年   7篇
  2005年   6篇
  2004年   2篇
  2003年   4篇
  2000年   2篇
  1999年   1篇
  1998年   1篇
  1994年   1篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
  1989年   2篇
  1985年   1篇
  1974年   1篇
排序方式: 共有769条查询结果,搜索用时 656 毫秒
71.
Waterlogging and salinity due to seepage from canals have polluted land and environment in various parts of Pakistan. A sustainable environment requires urgent remedial measures for this problem. The research in this paper presents the impacts of the Fourth Drainage Project, Faisalabad on the twin problem of waterlogging and salinity. Monitoring of the project was made on regular basis. The key performance indicators for the project include the lowering of water table, improvement of water quality and soil salinity, increase in area under cultivation, cropping intensity, and socioeconomic status of the project population. Data regarding water levels and discharge from the drain pipes were collected to monitor the impact on waterlogging. Soil samples were tested to evaluate the impact of drainage on land. It has been found that the percentage of the contaminated land in the project area has considerably been decreased, while the cropping intensities have been increased.  相似文献   
72.
The ability of cadmium uptake by metal-resistant yeast, Candida tropicalis, from the liquid medium and wastewater was evaluated. The minimum inhibitory concentration of Cd2?+? against C. tropicalis was 2,500 mg L???1. The yeast also showed tolerance toward Zn2?+? (1,400 mg L???1), Ni2?+? (1,000 mg L???1), Hg2?+? (1,400 mg L???1), Cu2?+? (1,000 mg L???1), Cr6?+? (1,200 mg L???1), and Pb2?+? (1,000 mg L???1). The yeast isolate showed typical growth curves, but lag and log phases extended in the presence of cadmium. The yeast isolate showed optimum growth at 30°C and pH 8. The metal processing ability of the isolate was determined in a medium containing 100 mg L???1 of Cd2?+?. C. tropicalis could decline Cd2?+? 70%, 85%, and 92% from the medium after 48, 96, and 144 h, respectively. C. tropicalis was also able to remove Cd2?+? 40% and 78% from the wastewater after 6 and 12 days, respectively. Cd produced an increase in glutathione (GSH) and nonprotein thiol levels by 135% and 134% at 100-mg L???1 concentration, respectively. An increase in the synthesis of GSH is involved in metal tolerance, and the presence of increasing GSH concentrations may be a marker for high metal stress in C. tropicalis. C. tropicalis, which is resistant to heavy metal ions and is adaptable to the local environmental conditions, may be employed for metal detoxification operations.  相似文献   
73.
Food and Environmental Virology - Drinking water supplies in the developing world often serve as a biosphere for various organisms. Viral gastroenteritis is a neglected area of research in...  相似文献   
74.
Journal of Polymers and the Environment - In this study, carboxymethyl chitosan with gum Arabic (CG) based novel functional films containing Cinnamomum camphora seeds extract (CCSE) at varying...  相似文献   
75.
Environmental Fluid Mechanics - The principle theme of this study is to introduce a novel countermeasure to reduce the energy of the overflowing floodwater by utilization of a water cushion. For...  相似文献   
76.

Polymer materials are vulnerable to damages, failures, and degradations, making them economically unreliable. Self-healing polymers, on the other hand, are multifunctional materials with superior properties of autonomic recovery from physical damages. These materials are suitable for biomedical and tissue engineering in terms of cost and durability. Schiff base linkages-based polymer materials are one of the robust techniques owing to their simple self-healing mechanism. These are dynamic reversible covalent bonds, easy to fabricate at mild conditions, and can self-reintegrate after network disruption at physiological conditions making them distinguished. Here we review self-healing polymer materials based on Schiff base bonds. We discuss the Schiff base bond formation between polymeric networks, which explains the self-healing phenomenon. These bonds have induced 100% recovery in optimal cases.

  相似文献   
77.
Environmental Science and Pollution Research - COVID-19, declared by the World Health Organization (WHO) to be a pandemic, has affected greenhouse gas emissions and contributed to the uncertainty...  相似文献   
78.
Environmental Science and Pollution Research - Climate change is a long-lasting change in the weather arrays across tropics to polls. It is a global threat that has embarked on to put stress on...  相似文献   
79.
Environmental Science and Pollution Research - Sunflower plants need nitrogen consistently and in higher amount for optimum growth and development. However, nitrogen use efficiency (NUE) of...  相似文献   
80.
Environmental Science and Pollution Research - In thirst for economic growth, economies are engaged in anti-environmental activities that drive them towards climate change and CO2 emissions....  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