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951.
952.
Michael A. Souffront Alcantara Christian Kesler Michael J. Stealey E. James Nelson Daniel P. Ames Norm L. Jones 《Journal of the American Water Resources Association》2018,54(4):859-871
Hydrologic modeling can be used to provide warnings before, and to support operations during and after floods. Recent technological advances have increased our ability to create hydrologic models over large areas. In the United States (U.S.), a new National Water Model (NWM) that generates hydrologic variables at a national scale was released in August 2016. This model represents a substantial step forward in our ability to predict hydrologic events in a consistent fashion across the entire U.S. Nevertheless, for these hydrologic results to be effectively communicated, they need to be put in context and be presented in a way that is straightforward and facilitates management‐related decisions. The large amounts of data produced by the NWM present one of the major challenges to fulfill this goal. We created a cyberinfrastructure to store NWM results, “accessibility” web applications to retrieve NWM results, and a REST API to access NWM results programmatically. To demonstrate the utility of this cyberinfrastructure, we created additional web apps that illustrate how to use our REST API and communicate hydrologic forecasts with the aid of dynamic flood maps. This work offers a starting point for the development of a more comprehensive toolset to validate the NWM while also improving the ability to access and visualize NWM forecasts, and develop additional national‐scale‐derived products such as flood maps. 相似文献
953.
Evaluation of Satellite‐Derived Rainfall Data for Multiple Physio‐Climatic Regions in the Santiago River Basin,Mexico 下载免费PDF全文
J.R. Ávila‐Carrasco H.E. Júnez‐Ferreira P.H. Gowda J.L. Steiner D.N. Moriasi P.J. Starks J. Gonzalez A.A. Villalobos C. Bautista‐Capetillo 《Journal of the American Water Resources Association》2018,54(5):1068-1086
Assessment of water resources requires reliable rainfall data, and rain gauge networks may not provide adequate spatial representation due to limited point measurements. The Tropical Rainfall Measuring Mission (TRMM) provides rainfall data at global scale, and has been used with good results. However, TRMM data are an indirect measurement of rainfall, and therefore must be validated for its proper use. In this work, a validation scheme was designed and implemented to compare the TRMM Version 7 (V7) monthly rainfall product at different time frames with data measured in two hydrologic subregions of the Santiago River Basin (SRB) in Mexico: Río Alto Santiago and Río Bajo Santiago (RBS). Additionally, three physio‐climatic regions provide an assessment of the interplay of topography, distance from coastal regions, and seasonal weather patterns on the correspondence between both datasets. The TRMM V7 rainfall product exhibited good agreement with the rain gauge data particularly for the RBS and for the whole SRB during wettest summer and autumn seasons. However, strong regional dependence was observed due to differences in climate and topography. Overall, in spite of some noted underestimations, the monthly TRMM V7 rainfall product was found to provide useful information that can be used to complement limited monitoring as is the case of RBS. An improved combined rainfall product could be generated and thus gaining the most benefits from both data sources. 相似文献
954.
James W. N. Steenberg Pamela J. Robinson Andrew A. Millward 《Journal of Environmental Planning and Management》2018,61(3):553-567
Urban forest ecosystems are complex and vulnerable social–ecological systems. The relationship between urban forests and housing is particularly variable and uncertain. We examine the influence of building renovation and rental housing on public trees at the parcel and street-section scale in a residential neighbourhood in Toronto, Canada. We use empirical data describing multiple tree inventories and government open data describing building permit applications to test for effects on urban forest structure, tree mortality, and tree planting. We found that the presence and number of building permits significantly predicted mortality at both scales, while planting was positively correlated with building permits at the street-section scale only. Multi-unit parcels had significantly lower rates of planting than single-unit parcels and multi-unit housing was positively correlated with mortality at the street-section scale. These findings suggest that where concentrated changes in housing stock are occurring, substantial losses of trees and associated ecosystem services are possible. 相似文献
955.
Maged Marghany 《环境科学学报(英文版)》2004,16(1):44-48
RADARSAT data have a potential role for coastal pollution monitoring. This study presents a new approach to detect and forecast oil slick trajectory movements. The oil slick trajectory movements is based on the tidal current effects and Fay‘s algorithm for oil slick spreading mechanisms. The oil spill trajectory model contains the integration between Doppler frequency shift model and Lagrangian model. Doppler frequency shift model implemented to simulate tidal current pattem from RADARSAT data while the Lagrangian model used to predict oil spill spreading pattern. The classical Fay‘s algorithm was implemented with the two models to simulate the oil spill trajectory movements. The study shows that the slick lengths are effected by tidal current V component with maximum velocity of 1.4 m/s. This indicates that oil slick trajectory path is moved towards the north direction. The oil slick parcels are accumulated along the coastline after 48 h. The analysis indicated that tidal current V components were the dominant forcing for oil slick spreading. 相似文献
956.
为探究矿工在应急场景下的脑电成分变化规律,研究通过脑电实验的方法对矿工在观看应急与正常作业场景下文字与图片素材的脑电数据进行分析.结果表明:矿工在实验素材的靶刺激下,ERP成分明显,且图片刺激效果强于文字,在200~400 ms时,P200,P300成分峰值最大;矿工大脑α节律不断下降,β节律不断上升,且β节律波幅面积... 相似文献
957.
958.
利用Matlab软件及Office组件函数编写了基于宏观经济指标进行地震灾害快速评估并自动生成灾害简报的程序。该程序可以充分利用天津地区高密度强震台网资源,也可以计算理论烈度下的灾害评估结果。程序利用的基础数据资料主要是乡镇级别的人口及区县级别的GDP统计数据,数据更新维护经济可靠。通过与天津市"十五"地震应急评估系统触发的342个地震灾害评估结果对比,表明二者之间相关性非常强,而该程序计算速度则快一个量级以上。程序涉及的数据处理及计算方法适合于大城市及城市群的地震灾害快速评估。 相似文献
959.
应用不同时期的TM图像,分别解译编制两期土壤侵蚀类型图。在地理信息系统(GIS)支持下,建立空间数据库。获得长武县土壤侵蚀动态图和动态转移数据矩阵,可以定位、定性、定量地显示前后两期间土壤侵蚀动态演变格局,并用Markov链模型对未来土壤侵蚀演变趋势进行模拟和预测。结果表明,研究区同时存在着"一边治理,一边破坏"的双重现象。 相似文献
960.
大气自动监测系统监测数据"有效性"讨论 总被引:2,自引:0,他引:2
根据统计推导出有效日均值允许缺测时数与允许误差和全日时均值均方差的理论关系式,应用于北京大气自动监测系统冬季二氧化硫小时浓度监测资料,计算出95%置信度下随机缺测允许最大时数为6h,与目前国家环保局要求75%数据捕获率相一致。 相似文献