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   99篇
  免费   1篇
  国内免费   1篇
安全科学   2篇
废物处理   1篇
环保管理   4篇
综合类   46篇
基础理论   13篇
环境理论   1篇
污染及防治   18篇
评价与监测   12篇
社会与环境   4篇
  2022年   4篇
  2021年   4篇
  2018年   2篇
  2017年   3篇
  2016年   2篇
  2014年   1篇
  2013年   5篇
  2012年   5篇
  2011年   3篇
  2010年   5篇
  2009年   7篇
  2008年   5篇
  2007年   2篇
  2006年   1篇
  2003年   1篇
  2002年   2篇
  2000年   1篇
  1998年   2篇
  1997年   1篇
  1994年   1篇
  1993年   1篇
  1990年   1篇
  1989年   1篇
  1988年   1篇
  1984年   1篇
  1983年   1篇
  1979年   1篇
  1977年   1篇
  1967年   2篇
  1966年   1篇
  1965年   5篇
  1964年   3篇
  1963年   2篇
  1962年   5篇
  1961年   2篇
  1960年   4篇
  1959年   2篇
  1958年   2篇
  1956年   2篇
  1955年   4篇
  1954年   2篇
排序方式: 共有101条查询结果,搜索用时 15 毫秒
61.
In this article, the proposed maximum power point tracking (MPPT) method is designed by taking rotor speed as an optimization problem, which is solved by artificial bee colony (ABC) algorithm to generate the maximum power output. The main advantage of this algorithm is that its optimal solution is independent of the initial positions and requirement of lesser number of control parameters, which leads to simple and robust MPPT algorithm than other algorithm. Furthermore, the hill climb search and particle swarm optimization-based MPPT algorithm are also discussed and the results obtained by these are compared to verify the effectiveness of proposed algorithm. Simulations for MPPT control along with doubly fed induction-generator-based wind energy conversion system is carried out in MATLAB/Simulink environment. Three statistical methods are used to evaluate the accuracy of each MPPT algorithm. All results are analyzed and compared under randomly selected wind as well as real wind speed configuration. Comparison of both numerical and simulation results under two different varying wind speed conditions strongly suggest that the proposed ABC-based MPPT algorithm is superior than other two MPPT algorithms.  相似文献   
62.
Human populations are using oceans as their household dustbins, and microplastic is one of the components which are not only polluting shorelines but also freshwater bodies globally. Microplastics are generally referred to particles with a size lower than 5 mm. These microplastics are tiny plastic granules and used as scrubbers in cosmetics, hand cleansers, air-blasting. These contaminants are omnipresent within almost all marine environments at present. The durability of plastics makes it highly resistant to degradation and through indiscriminate disposal they enter in the aquatic environment. Today, it is an issue of increasing scientific concern because these microparticles due to their small size are easily accessible to a wide range of aquatic organisms and ultimately transferred along food web. The chronic biological effects in marine organisms results due to accumulation of microplastics in their cells and tissues. The potential hazardous effects on humans by alternate ingestion of microparticles can cause alteration in chromosomes which lead to infertility, obesity, and cancer. Because of the recent threat of microplastics to marine biota as well as on human health, it is important to control excessive use of plastic additives and to introduce certain legislations and policies to regulate the sources of plastic litter. By setup various plastic recycling process or promoting plastic awareness programmes through different social and information media, we will be able to clean our sea dustbin in future.  相似文献   
63.

SARS-CoV-2 pandemic continues with emergence of new variants of concerns. These variants are fueling the third and fourth waves of pandemic across many nations. Here we describe the new emerging variants of SARS-CoV-2 and why they have enhanced infectivity and possess the ability to evade immunity.

  相似文献   
64.
This report describes a simple chemical free method that was successfully used by a team of European and Indian scientists (www.qub.ac.uk/tipot) to remove arsenic (As) from groundwater in a village in West Bengal, India. Six such plants are now in operation and are being used to supply water to the local population (www.insituarsenic.org). The study was conducted in Kasimpore, a village in North 24 Parganas District, approximately 25 km from Kolkata. In all cases, total As in treated water was less than the WHO guideline value of 10 μg L−1. The plant produces no sludge and the operation cost is 1.0 US$ per day for producing 2000 L of potable water.  相似文献   
65.
66.
67.
68.
69.
70.
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