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   4836篇
  免费   44篇
  国内免费   55篇
安全科学   131篇
废物处理   283篇
环保管理   401篇
综合类   777篇
基础理论   968篇
环境理论   4篇
污染及防治   1571篇
评价与监测   456篇
社会与环境   306篇
灾害及防治   38篇
  2023年   48篇
  2022年   160篇
  2021年   171篇
  2020年   93篇
  2019年   95篇
  2018年   181篇
  2017年   174篇
  2016年   243篇
  2015年   155篇
  2014年   230篇
  2013年   373篇
  2012年   262篇
  2011年   333篇
  2010年   234篇
  2009年   197篇
  2008年   233篇
  2007年   240篇
  2006年   165篇
  2005年   182篇
  2004年   223篇
  2003年   207篇
  2002年   144篇
  2001年   105篇
  2000年   61篇
  1999年   50篇
  1998年   26篇
  1997年   29篇
  1996年   24篇
  1995年   32篇
  1994年   27篇
  1993年   14篇
  1992年   19篇
  1991年   17篇
  1990年   14篇
  1989年   12篇
  1988年   7篇
  1987年   11篇
  1986年   10篇
  1985年   11篇
  1984年   12篇
  1983年   12篇
  1982年   7篇
  1981年   10篇
  1979年   10篇
  1975年   4篇
  1967年   3篇
  1966年   3篇
  1964年   5篇
  1961年   3篇
  1958年   3篇
排序方式: 共有4935条查询结果,搜索用时 15 毫秒
81.
Performance evaluation is important in managing freight transport. The transport of certain products, especially those that are hazardous, can have significant financial and socio-environmental impacts. This article presents an application of the modal choice method (MCM) to establish an order of priority among the alternatives considered to carry a determined hazardous product. After a research of the literature on the concepts and development of the proposed method, we consulted experts about their experiences and knowledge, to determine a set of relevant attributes for the evaluation process. We then applied this method to the specific case of the Brazilian bio-ethanol industry, to demonstrate the potential of using the MCM as a tool to support make decisions. We can conclude that highway transport, though the most often used, is not the best compared to trains or pipelines (or combinations of any of the three) from a socio-environmental standpoint. Alternatives with longer pipeline segments are the most suitable to replace the current practice in environmental terms.  相似文献   
82.
We here examine species distribution models for a Neotropical anuran restricted to ombrophilous areas in the Brazilian Atlantic Forest hotspot. We extend the known occurrence for the treefrog Hypsiboas bischoffi (Anura: Hylidae) through GPS field surveys and use five modeling methods (BIOCLIM, DOMAIN, OM-GARP, SVM, and MAXENT) and selected bioclimatic and topographic variables to model the species distribution. Models were first trained using two calibration areas: the Brazilian Atlantic Forest (BAF) and the whole of South America (SA). All modeling methods showed good levels of predictive power and accuracy with mean AUC ranging from 0.77 (BIOCLIM/BAF) to 0.99 (MAXENT/SA). MAXENT and SVM were the most accurate presence-only methods among those tested here. All but the SVM models calibrated with SA predicted larger distribution areas when compared to models calibrated in BAF. OM-GARP dramatically overpredicted the species distribution for the model calibrated in SA, with a predicted area around 106 km2 larger than predicted by other SDMs. With increased calibration area (and environmental space), OM-GARP predictions followed changes in the environmental space associated with the increased calibration area, while MAXENT models were more consistent across calibration areas. MAXENT was the only method that retrieved consistent predictions across calibration areas, while allowing for some overprediction, a result that may be relevant for modeling the distribution of other spatially restricted organisms.  相似文献   
83.
This work is a part of a wider study involving the economic and environmental implications of managing construction and demolition waste (CDW), focused on the operation of a large scale CDW recycling plant. This plant, to be operated in the Lisbon Metropolitan Area (including the Setúbal peninsula), is analysed for a 60 year period, using primary energy consumption and CO2eq emission impact factors as environmental impact performance indicators.Simplified estimation methods are used to calculate industrial equipment incorporated, and the operation and transport related impacts. Material recycling – sorted materials sent to other industries, to act as input – is taken into account by discounting the impacts related to industrial processes no longer needed.This first part focuses on calculating the selected impact factors for a base case scenario (with a 350 tonnes/h installed capacity), while a sensitivity analysis is provided in part two. Overall, a 60 year global primary energy consumption of 71.4 thousand toe (tonne of oil equivalent) and a total CO2eq emission of 135.4 thousand tonnes are expected. Under this operating regime, around 563 thousand toe and 1465 thousand tonnes CO2eq could be prevented by replacing raw materials in several construction materials industries (e.g.: ferrous and non-ferrous metals, plastics, paper and cardboard).  相似文献   
84.
85.
Environmental Science and Pollution Research - For the photocatalytic degradation of antioxidant 2,6-di-tert-butyl-hydroxytoluene (BHT), several TiO2-based composites have been prepared in MWCNT...  相似文献   
86.
Environmental Science and Pollution Research - The order Odonata has been regularly used as an indicator of the ecosystem’s condition. The objective of this review was to analyze the...  相似文献   
87.
Environmental Science and Pollution Research - In this work, the activated persulfate oxidation of ciprofloxacin (CIP) using a low-grade titanium ore under sunlight or simulated sunlight were...  相似文献   
88.
Environmental Science and Pollution Research - This work proposes a novel approach for the coupling of ozonation and Fenton processes using a new prototype of a high rotation bubble reactor (HRBR),...  相似文献   
89.
Environmental Science and Pollution Research - The process TiO2/PAC/UV-vis has been under study and compared with the isolated treatments of adsorption and photocatalysis determining possible...  相似文献   
90.
Environmental Science and Pollution Research - This paper presents the synthesis of a hybrid material through the use of natural pozzolan and titanium(IV) isopropoxide using the sol-gel method and...  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