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   346篇
  免费   3篇
  国内免费   2篇
安全科学   13篇
废物处理   10篇
环保管理   37篇
综合类   20篇
基础理论   76篇
污染及防治   119篇
评价与监测   51篇
社会与环境   25篇
  2023年   7篇
  2022年   15篇
  2021年   16篇
  2020年   7篇
  2019年   8篇
  2018年   18篇
  2017年   11篇
  2016年   35篇
  2015年   15篇
  2014年   27篇
  2013年   31篇
  2012年   19篇
  2011年   27篇
  2010年   17篇
  2009年   9篇
  2008年   18篇
  2007年   18篇
  2006年   10篇
  2005年   6篇
  2004年   4篇
  2003年   4篇
  2002年   3篇
  2001年   5篇
  2000年   3篇
  1999年   3篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1994年   3篇
  1993年   2篇
  1991年   2篇
  1990年   1篇
  1979年   2篇
  1976年   1篇
  1966年   1篇
排序方式: 共有351条查询结果,搜索用时 15 毫秒
161.
Argentinian agricultural production is fundamentally based on a technological package that combines no-till and glyphosate in the cultivation of transgenic crops. Transgenic crops (soybean, maize and cotton) occupy 23 million hectares. This means that glyphosate is the most employed herbicide in the country, where 180–200 million liters are applied every year.  相似文献   
162.
The Brazilian program of payment for environmental services (PES) is based on ranges of potential erosion decrease (ED) from soil and water conservation proposals estimated from the Universal Soil Loss Equation. Changes in land use and land cover (LULC) result in many alterations of the basin water balance. Therefore, to contribute to the methodological development of Brazilian PES, this paper proposes a quantification of hydrological benefits based on conservation measures. We propose basing the PES program on adding the potential water storage increase (WSI) parameter estimated from the runoff curve number model. Two LULC change scenarios were run considering conservation measures on degraded areas. We found that indicators of ED and WSI were compatible tools for driving the eligibility of soil and water conservation measures. However, the water storage parameter seems to be better at managing the PES mechanism because it is based on water prices and can contribute to appreciation of the efforts performed by the rural producers. The use of the SCS-CN method presents greater feasibility as a tool for the implementation of PES programs in ungauged basins. Thus, an analysis of the success of the innovation proposal of the Brazilian PES program allows inferences to be made about the quantification and financial valuation of hydrological benefits of the potential storage increase and current water price.  相似文献   
163.

Low-density polyethylene (LDPE), biaxially oriented polypropylene (BOPP), and expanded polystyrene (EXPS) are the most common plastics found in every home of the world, but only ~ 10% enter the recycling chains. Consequently, the study of plastic biodegradation by microorganisms and insects, such as the wax moths, has gained special interest. Galleria mellonella (L.) has been shown to consume single-layered polyethylene and polystyrene, though biological impacts of this consumption have been rarely reported. We evaluated the consumption of different plastics by G. mellonella larvae (L7, mean size: 25–30 mm) and its effect on larval duration, survival, and development. For this, we offered the larvae five diets: single-layered LDPE, EXPS, BOPP, triple-layered polyethylene (SB, for silo-bags), and a control with beeswax. We recorded the state and weight of the materials and the state of larvae until they reached the adult stage. Larvae consumed more PE (both LDPE and SB) and EXPS than BOPP; still, they were able to emerge as adults in all treatments. Larvae that consumed plastics turned into pupal stage faster than those that consumed beeswax, regardless of the type and amount of plastic consumed. This is the first report of wild G. mellonella larvae in Argentina consuming biaxially polypropylene and silo-bags.

  相似文献   
164.
Environmental Science and Pollution Research - Balneotherapy (BT) is one of the most commonly used non-pharmacologic complementary therapies for different rheumatic diseases. Its beneficial...  相似文献   
165.
Environmental Science and Pollution Research - A new one-pot synthesis method optimized by a 23 experimental design was developed to prepare a biosorbent, sugarcane bagasse cellulose succinate...  相似文献   
166.
167.
The Instituto de Radioprote??o e Dosimetria has been coordinating the National Intercomparison Program (PNI) for 15 years, from 1991 to 2005. The objective is to evaluate the analytical performance of the laboratories in low-level activity concentration radionuclide assays in environmental samples. This work presents an evaluation of PNI data from 42 intercomparison runs, which distributed to 22 Brazilian laboratories 2511 samples evaluating 5768 radionuclide assays involving 32 radionuclides in the period from 1991 to 2004. The laboratory performance was evaluated using the Normalized Standard Deviation used by the U.S. EPA. For comparison aims, the Normalized Deviation, used by BIPM was also applied. Laboratory performance were grouped and evaluated in three periods of 5 years each. The first period shows, an average value of good performance of 71.2%, the second shows an average of 78.6% and the last an average of 82.3%. Performance for each kind of radionuclide is also presented.  相似文献   
168.
169.
Wastewater from wash down of boat hulls contains typically Cu, Zn and organometallic biocides, e.g. tributyltin (TBT). In some cases this wastewater is led directly into the marine system. In the present paper, a cheap flocculation method (iron flocculants) for removal of Cu and Zn from the wastewater is investigated and the method was shown successful. TBT concentration in a sample from a German dockyard was also decreased during flocculation, but the TBT removed was already associated with small particulates in the original sample. Low concentrations of heavy metals were obtained by flocculation: <0.05 mg Cu/l and 0.2 mg Zn/l. An erratum to this article can be found at  相似文献   
170.
Non-amended soils affected by pyritic sludge residues were monitored for 7 years to assess the long-term natural attenuation ability of these soils. The decrease in both the total concentration of elements (particularly As) and (NH(4))(2)SO(4)-extractable fractions of Mn, and Zn, below the maximum permissible levels indicate a successful natural ability to attenuate soil pollution. Soil acidification by pyrite oxidation and rainfall-enhanced leaching were the largest contributors to the reduction of metals of high (Mn, Cu, Zn and Cd) and low (Fe, Al, and As) availability. Periodic use of correlation and spatial distribution analysis was useful in monitoring elemental dispersion and soil property/element relationships.  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