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   311篇
  免费   0篇
  国内免费   12篇
安全科学   8篇
废物处理   27篇
环保管理   17篇
综合类   27篇
基础理论   35篇
环境理论   1篇
污染及防治   155篇
评价与监测   36篇
社会与环境   17篇
  2023年   10篇
  2022年   56篇
  2021年   41篇
  2020年   12篇
  2019年   15篇
  2018年   14篇
  2017年   22篇
  2016年   14篇
  2015年   13篇
  2014年   18篇
  2013年   27篇
  2012年   9篇
  2011年   15篇
  2010年   12篇
  2009年   7篇
  2008年   7篇
  2007年   8篇
  2006年   2篇
  2005年   1篇
  2004年   2篇
  2003年   1篇
  2002年   2篇
  2000年   2篇
  1999年   1篇
  1997年   1篇
  1992年   1篇
  1990年   1篇
  1985年   2篇
  1984年   1篇
  1980年   1篇
  1979年   2篇
  1972年   1篇
  1964年   1篇
  1963年   1篇
排序方式: 共有323条查询结果,搜索用时 0 毫秒
11.
Environmental Science and Pollution Research - Recent research has shown a huge impact of non-renewable energy (NRE) production on environmental health. In this context, this work analyzes the...  相似文献   
12.
Environmental Science and Pollution Research - Over the last few decades, economic policy uncertainty (EPU) has surged across the globe. Furthermore, EPU affects economic activities, which may also...  相似文献   
13.
Environmental Science and Pollution Research - Anthropogenic activities have increased atmospheric concentrations of greenhouse gas emissions, which have observably increased global temperature....  相似文献   
14.
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   
15.
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   
16.
Environmental Science and Pollution Research - This study examines the endogenous growth theory for technological innovation and economic growth with the role of foreign direct investment (FDI) and...  相似文献   
17.
Vegetable oils are used as raw materials for biodiesel production using transesterification reaction. Several methods for the production of biodiesel were developed using chemical (alkali and acidic compounds) and biological catalysts (lipases). Biodiesel production catalyzed by lipases is energy and cost-saving processes and is carried out at normal temperature and pressure. The need for an efficient method for screening larger number of variables has led to the adoption of statistical experimental design. In the present study, packed bed reactor was designed to study with mixed immobilized biocatalysts to have higher productivity under optimum conditions. Contrary to the single-step acyl migration mechanism, a two-step stepwise reaction mechanism involving immobilized Candida rugosa lipase and immobilized Rhizopus oryzae cells was employed for the present work. This method was chosen because enzymatic hydrolysis followed by esterification can tolerate high free fatty acid containing oils. The effects of flow rate and bed height on biodiesel yield were studied using two factors five-level central composite design (CCD) and response surface methodology (RSM). Maximum biodiesel yield of 85 and 81 % was obtained for jatropha oil and karanja oil with the optimum bed height and optimum flow rate of 32.6 cm and 1.35 L/h, and 32.6 cm and 1.36 L/h, respectively.  相似文献   
18.
19.
Abstract

The effect of mercuric chloride (HgCl2) on the activities of catalase, Superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and its effect on glutathione (GSH) content were evaluated in different organs (liver, kidneys, and brain) of mice after administration at 0, 0.25, 0.5 and 1.0 mg/kg/day for 14 days. The uptake of mercury shows that the kidneys accumulated the highest levels of mercury compare to brain and liver. The enzyme levels varied in mercury treated organs compare to control. A dose dependent increase of antioxidant enzymes occurred in the liver and kidneys. The increase in enzyme activities correlated with highest mercury accumulation in the kidneys and liver. Mercury is known to generate reactive oxygen species (ROS) in vivo and in vitro, therefore, it is likely that enzyme activities increased to scavenge ROS levels produced as a result of mercury accumulation. Glutathione content increased in liver and kidneys of mercury treated mice compare to control. The results showed that the highest oral dose of mercury significantly increased antioxidant enzymes in kidneys and liver. The increased antioxidant enzymes enhance the antioxidant potential of the organs to reduce oxidative stress.  相似文献   
20.
Web-based surveys were sent to Canadian certified ergonomists, Joint Health and Safety Committees (JHSCs) and health and safety certification trainers to understand better which ergonomics analysis tools were used in industry and help JHSCs obtain the necessary training required to reduce work-related musculoskeletal disorders (WMSDs). The results showed that most of the certified ergonomists used the Snook/Mital tables, the National Institute of Occupational Safety and Health (NIOSH) equation and rapid upper limb assessment (RULA) /rapid entire body assessment (REBA). The most frequently used methods by JHSCs to identify ergonomics risk were injury reports and worker complaints. The surveys for the health and safety certification trainers revealed that most curricula did not include ergonomics analysis tools. There appears to be a gap between what is recommended by certified ergonomists for JHSC, what is taught in training and what is used by JHSCs for ergonomics risk analysis. A better understanding, modifications in training curricula and education of JHSCs are needed to help reduce WMSDs.  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