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   30355篇
  免费   345篇
  国内免费   457篇
安全科学   951篇
废物处理   1444篇
环保管理   3677篇
综合类   5070篇
基础理论   7954篇
环境理论   18篇
污染及防治   8020篇
评价与监测   2072篇
社会与环境   1773篇
灾害及防治   178篇
  2023年   134篇
  2022年   316篇
  2021年   316篇
  2020年   240篇
  2019年   284篇
  2018年   478篇
  2017年   478篇
  2016年   742篇
  2015年   569篇
  2014年   885篇
  2013年   2417篇
  2012年   1061篇
  2011年   1439篇
  2010年   1169篇
  2009年   1197篇
  2008年   1438篇
  2007年   1486篇
  2006年   1263篇
  2005年   1094篇
  2004年   983篇
  2003年   1076篇
  2002年   950篇
  2001年   1238篇
  2000年   863篇
  1999年   517篇
  1998年   347篇
  1997年   358篇
  1996年   356篇
  1995年   423篇
  1994年   446篇
  1993年   353篇
  1992年   374篇
  1991年   352篇
  1990年   386篇
  1989年   341篇
  1988年   296篇
  1987年   278篇
  1986年   223篇
  1985年   249篇
  1984年   265篇
  1983年   256篇
  1982年   241篇
  1981年   222篇
  1980年   175篇
  1979年   194篇
  1978年   176篇
  1975年   140篇
  1974年   117篇
  1972年   130篇
  1971年   131篇
排序方式: 共有10000条查询结果,搜索用时 515 毫秒
971.
Journal of Material Cycles and Waste Management - Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the...  相似文献   
972.
Journal of Material Cycles and Waste Management - Fused filament fabrication (FFF) based additive manufacturing (AM) process is a widely used and emerging manufacturing process for...  相似文献   
973.
Russian Journal of Ecology - The long-term dynamics (over more than 70 years) of pike infection by cestodes Triaenophorus crassus and T. nodulosus in the Rybinsk Reservoir (the Volga River) has...  相似文献   
974.
Russian Journal of Ecology - A study of the anthropogenic impacts on the on-shore aggregation of true seals was carried out at a haul-out located at the mouth of Piltun Bay (the northeastern part...  相似文献   
975.
Russian Journal of Ecology - Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study,...  相似文献   
976.
Environment, Development and Sustainability - The current study explores the role of green trust, green perceived risk and green perceived quality in changing green purchase intention....  相似文献   
977.
Environment, Development and Sustainability - The COVID-19 pandemic has caused a global emergence, and the absence of a proven vaccine or medicine has led to the implementation of measures to...  相似文献   
978.
Environmental Economics and Policy Studies - Streets are an essential element of cities, and their design has a profound impact on their functionality to the movement of people and their...  相似文献   
979.
This study explores the viability of using simulated monthly runoff as a proxy for landscape‐scale surface‐depression storage processes simulated by the United States Geological Survey’s National Hydrologic Model (NHM) infrastructure across the conterminous United States (CONUS). Two different temporal resolution model codes (daily and monthly) were run in the NHM with the same spatial discretization. Simulated values of daily surface‐depression storage (treated as a decimal fraction of maximum volume) as computed by the daily Precipitation‐Runoff Modeling System (NHM‐PRMS) and normalized runoff (0 to 1) as computed by the Monthly Water Balance Model (NHM‐MWBM) were aggregated to monthly and annual values for each hydrologic response unit (HRU) in the CONUS geospatial fabric (HRU; n = 109,951) and analyzed using Spearman’s rank correlation test. Correlations between simulated runoff and surface‐depression storage aggregated to monthly and annual values were compared to identify where which time scale had relatively higher correlation values across the CONUS. Results show Spearman’s rank values >0.75 (highly correlated) for the monthly time scale in 28,279 HRUs (53.35%) compared to the annual time scale in 41,655 HRUs (78.58%). The geographic distribution of HRUs with highly correlated monthly values show areas where surface‐depression storage features are known to be common (e.g., Prairie Pothole Region, Florida).  相似文献   
980.
Gridded precipitation datasets are becoming a convenient substitute for gauge measurements in hydrological modeling; however, these data have not been fully evaluated across a range of conditions. We compared four gridded datasets (Daily Surface Weather and Climatological Summaries [DAYMET], North American Land Data Assimilation System [NLDAS], Global Land Data Assimilation System [GLDAS], and Parameter‐elevation Regressions on Independent Slopes Model [PRISM]) as precipitation data sources and evaluated how they affected hydrologic model performance when compared with a gauged dataset, Global Historical Climatology Network‐Daily (GHCN‐D). Analyses were performed for the Delaware Watershed at Perry Lake in eastern Kansas. Precipitation indices for DAYMET and PRISM precipitation closely matched GHCN‐D, whereas NLDAS and GLDAS showed weaker correlations. We also used these precipitation data as input to the Soil and Water Assessment Tool (SWAT) model that confirmed similar trends in streamflow simulation. For stations with complete data, GHCN‐D based SWAT‐simulated streamflow variability better than gridded precipitation data. During low flow periods we found PRISM performed better, whereas both DAYMET and NLDAS performed better in high flow years. Our results demonstrate that combining gridded precipitation sources with gauge‐based measurements can improve hydrologic model performance, especially for extreme events.  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