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   625篇
  免费   16篇
  国内免费   7篇
安全科学   13篇
废物处理   60篇
环保管理   62篇
综合类   67篇
基础理论   126篇
环境理论   1篇
污染及防治   185篇
评价与监测   72篇
社会与环境   56篇
灾害及防治   6篇
  2023年   17篇
  2022年   53篇
  2021年   41篇
  2020年   21篇
  2019年   18篇
  2018年   48篇
  2017年   28篇
  2016年   35篇
  2015年   30篇
  2014年   39篇
  2013年   60篇
  2012年   25篇
  2011年   34篇
  2010年   20篇
  2009年   22篇
  2008年   25篇
  2007年   23篇
  2006年   24篇
  2005年   15篇
  2004年   12篇
  2003年   18篇
  2002年   13篇
  2001年   12篇
  2000年   4篇
  1999年   1篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1992年   4篇
  1985年   1篇
  1969年   1篇
排序方式: 共有648条查询结果,搜索用时 15 毫秒
191.
As a consequence of the nuclear accident that took place in Palomares (Almería, Spain) more than 40 years ago, actinides contamination is present in the area nowadays. Previous investigations performed with soil samples collected in different locations of Palomares indicate that the contamination in the area is highly inhomogeneous, suggesting the existence of radioactive particles, thus hindering the evaluation of the radiological situation. This work presents the methodology used for the location of the radioactive particles in the field and their isolation in the laboratory for further speciation and characterization studies. Colour pictures, electron microscopy images and EDX analyses show that most of the studied particles present a granular appearance with a variable grain size and a high fragmentation tendency, being plutonium and uranium the most abundant nuclear elements. Radiochemical determinations and activity isotopic ratios prove that the nuclear material is aged weapon grade plutonium arising from the Palomares accident.  相似文献   
192.
Environmental Science and Pollution Research - Although anaerobic reactors are an excellent alternative in the treatment of domestic effluents, they have the disadvantage of requiring...  相似文献   
193.
Environmental Science and Pollution Research - Pesticides have been used to kill pests such as insects, fungi, rodents, and unwanted plants. Since these compounds are potentially toxic to the...  相似文献   
194.
Environmental Science and Pollution Research - The indiscriminate use of fertilizers and chemical pesticides can lead to boron contamination of the soil. Decontamination in general is expensive and...  相似文献   
195.

This paper analyzes the impact of international oil price uncertainty on the different economic sectors (primary, secondary, and tertiary) in Mexico in the period 1993:1–2020:4 through a bivariate structural vector autoregressive (VAR) model with a generalized autoregressive conditional heteroskedasticity (GARCH) in mean to capture the impact of oil volatility on economic growth at the sectoral level of economic activity. The results show that the uncertainty of the international price of oil has a differentiated effect on the different sectors of economic activity in Mexico since it does not influence the primary sector; it negatively impacts the secondary sector, and there is mixed evidence in the tertiary sector. Additionally, evidence is provided that both positive and negative shocks to the international oil price have asymmetric effects at the sectoral level in Mexico. The results highlight the need to implement public policies, at the country level, that help mitigate the effect of uncertainty in the oil market and promote economic stability at the sector level.

  相似文献   
196.
Journal of Polymers and the Environment - This work aimed to investigate the biopolyethylene (BioPE)/wood powder (WP) composites compatibilized with polyethylene-grafted maleic anhydride (PE-g-MA),...  相似文献   
197.
Journal of Polymers and the Environment - The paper studied the influence of a catalyst, comparing it with its traditional counterparts, in the process of obtaining a polyethylene terephthalate...  相似文献   
198.
Journal of Polymers and the Environment - Exposure to potentially toxic metallic elements (PTME) released in watercourses by industries results in irreversible damage to living beings or even...  相似文献   
199.
Pharmaceuticals and illicit drugs are contaminants that are generally ubiquitous in wastewater treatment plant effluents with their release into the environment being well understood in North America, Europe, and Asia. There is, however, less information on the release of human pharmaceuticals and illicit drugs from regions undergoing rapid land use, economical, and social changes, such as Brazil. This encompasses many areas in the tropical zone where releases of emerging contaminants may impact pristine, bio‐diversity rich ecosystems. In this study, the occurrence of human pharmaceuticals and the illicit drug cocaine was determined in the Rio Negro and two of its tributaries that receive large amounts of untreated sewage, the Igarapé Mindu and the Igarapé do 40, passing through the city of Manaus, Brazil. In addition to cocaine and its metabolite, benzoylecognine, propranolol, diclofenac, amitriptyline, carbamazepine, carbamazepine‐epoxide, citalopram, metoprolol, carisoprolol, and sertraline were all detected in two urban tributaries at low ng/l concentrations similar to those typically found in urban surface waters. Concentrations in the Rio Negro were typically lower than detection limits due to the large level of dilution, although traces of a range of pharmaceuticals were detected in the Rio Negro in proximity of the confluence of the urban streams. The data represent new information on the emissions of pharmaceuticals from a newly industrialized region of Brazil.  相似文献   
200.
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