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871.
系统梳理了国家“水体污染控制与治理科技重大专项”在“十一五”和“十二五”期间有关课题产出的城镇降雨径流污染控制关键技术,通过对其进行技术和系统成熟度评价来解析我国城镇降雨径流污染控制技术的发展水平和面临挑战,为进一步推进相关技术的发展提供参考。结果表明:我国在城镇降雨径流污染控制技术领域已开展了大量研究工作,研发和应用的大部分单项关键技术的技术成熟度已达到7级,可在一定程度上解决我国城镇径流污染问题;在城镇降雨径流污染控制技术体系中,支撑技术系统成熟度为4级,达到系统发展验证阶段,能够用于开展系统的工程设计,减少集成风险;4个关键技术环节和城镇降雨径流污染控制技术系列的系统成熟度分别为3级和2级,在技术环节和系列方面仅仅形成系统及设计开发策略,能在一定程度上降低系统集成风险,形成组合技术。因此,我国城镇降雨径流污染控制技术的单项技术成熟度还需进一步提高,以加强技术和系统的集成,并开展集成创新,使整体技术系列能达到满足任务需求的设计、运行和处理能力,在系统生命周期内向应用效益最佳的方向优化和发展。  相似文献   
872.
《Environmental Hazards》2013,12(3):181-199
Superstorm Sandy was an unprecedented meteorological event that devastated the Caribbean and the Northeastern Coast of the USA in October 2012. While many research efforts will focus on the atmospheric conditions that led to the creation and unusual track of the storm, this study evaluates the impact of Sandy on voter turnout in the 2012 US Presidential Election. The goals of this paper are to (1) determine if any alterations in voter turnout occurred, (2) assess the extent to which Sandy was responsible for any voter turnout changes and (3) investigate if the influence of Sandy on voter turnout was contingent upon social vulnerability. To accomplish these goals, voter turnout change between the 2008 and 2012 US Presidential Elections was analysed at the county and municipal level for both New Jersey and Connecticut. The notable decreases in voter turnout discovered in both states were likely due to the election occurring in the aftermath of Superstorm Sandy. The correlation, spatial clustering analysis, analysis of variance and multiple regression results all suggest that storm surge was more likely to be responsible for reduced voter turnout in New Jersey than in Connecticut. Specifically in New Jersey, the findings indicate that storm surge coverage, rather than height, was influential in reducing voter turnout and that this relationship was contingent upon the racial composition of the municipalities. Overall, understanding how Sandy affected voter turnout will help improve the resiliency of electoral systems to future natural disasters.  相似文献   
873.
Abstract: While training a Neural Network to model a rainfall‐runoff process, generally two aspects are considered: its capability to be able to describe the complex nature of the processes being modeled and the ability to generalize so that novel samples could be mapped correctly. The general conclusion is that, the smallest size network capable of representing the sample distribution is the best choice, as far as generalization is concerned. Oftentimes input variables are selected a priori in what is called an explanatory data analysis stage and are not part of the actual network training and testing procedures. When they are, the final model will have only a “fixed” type of inputs, lag‐space, and/or network structure. If one of these constituents was to change, one would obtain another equally “optimal” Neural Network. Following Beven and others' generalized likelihood uncertainty estimate approach, a methodology is introduced here that accounts for uncertainties in network structures, types of inputs, and their lag‐space relationships by looking at a population of Neural Networks rather than target in getting a single “optimal” network. It is shown that there is a wide array of networks that provide “similar” results, as seen by a likelihood measure, for different types of inputs, lag‐space, and network size combinations. These equally optimal networks expose the range of uncertainty in streamflow predictions and their expected value results in a better performance than any of the single network predictions.  相似文献   
874.
The validity of a steady-state massbalance model (Arp et al., 1996; referred to asARP) was tested using physicochemical soil data fromthe Monitoring Acid Rain Youth Program (MARYP). FourARP sites were matched with ten MARYP sites accordingto proximity, bedrock type and subsoil pH to test thevalidity of the ARP model for critical loadexceedances. Soil solution pH, base concentration andAl concentration from MARYP sites, which were wellmatched to ARP sites, validated the modelled criticalload exceedances. Higher exceedance areas wereassociated with more acidic pH and lower base andhigher Al concentrations from matched MARYP sites andvice versa. One ARP site was inappropriately matchedwith MARYP sites and could not be validated using baseand Al concentrations. This study also confirmed thesouthern limit of the zero critical load exceedanceisopleth from the model. However, variability of theother exceedance isopleths was noted due to thelimited number of sites used in the model. Thevalidation of these sites in the ARP model and thezero critical load exceedance isopleth nonethelessallows greater confidence in using this model as amanagement tool for acidic deposition.  相似文献   
875.
Curtis  C. J.  Barbieri  A.  Camarero  L.  Gabathuler  M.  Galas  J.  Hanselmann  K.  Kopaček  J.  Mosello  R.  Nickus  U.  Rose  N.  Stuchlik  E.  Thies  H.  Ventura  M.  Wright  R. 《Water, Air, & Soil Pollution: Focus》2002,2(2):115-126
Critical load models for acidityprovide a measure of the sensitivity of surfacewaters to acid deposition, and can be used todetermine critical load exceedance and potentiallong-term harmful effects. Three static models,the Steady-State Water Chemistry model, diatommodel and First-order Acidity Balance model, arehere applied to 11 high mountain lakes in Norway,Scotland, the Alps, the Pyrenees and the Tatras.Between five and seven of the lakes show criticalload exceedance, depending on the model used.Nitrogen as well as sulphur deposition isimportant in causing exceedance. Since soil andvegetation cover are generally sparse, geologyand lake retention time appear to be key factorsin the determination of critical load. Retentionof nitrogen is observed, but it is unclearwhether this occurs within the lake or theterrestrial part of the catchment.  相似文献   
876.
Critical Loads and levels have played a centralrole in the successful development of effect-based emissionreduction strategies for Europe in the fields of acidification,eutrophication and ground-level ozone. The aim of theInternational Programme on Mapping Critical Loads and Levelsled by Germany, with participation of 24 countries, is todetermine critical loads and levels for forest, crops, naturalvegetation, soils, water and materials. The exceedances ofcritical loads and critical levels are used to quantify the riskfor environmental damage by air pollution and tosupport the development of optimised abatement strategies.  相似文献   
877.
There is an increasing demand from conservation agencies for site-specific critical loads (CL); unfortunately, there is often very little specific information on a site to determine the important parameters needed to calculate the CL or on the spatial location of the “designated feature” in a site. Determining the most appropriate CL therefore involves using expert judegement to make decisions with incomplete and uncertain information. Endorsement Theory (Cohen, 1985) and Dempster–Shafer statistics (Dempster, 1967; Shafer, 1976) are, respectively, a decision-theoretic and a statistical technique for reasoning under those conditions (uncertainty and incompletness). A key reason for applying these techniques is that they make expert opinion explicit and available for scrutiny. Both techniques have been applied to the problem of setting an appropriate site specific CL, using heathland sites as a case study. Inital findings are encouraging; the uncertainty in expert judgement is made explict, the end results are intuitively reasonable and the methodology apparently acceptable to decision makers.  相似文献   
878.
分析了1960—2003年内蒙古赤峰地区69次沙尘暴天气过程的环流形势,重点讨论了高低层系统的相互配置;根据沙尘暴的观测资料,以造成内蒙古赤峰地区沙尘暴的主要地面环流系统为依据,通过综合分析归纳,将形成沙尘暴的环流系统划分为蒙古气旋、高压前偏北大风、冷锋过境、东低西高和南高北低型等5种环流形势,供本地沙尘暴天气过程的预报参考。  相似文献   
879.
Bosher L  Carrillo P  Dainty A  Glass J  Price A 《Disasters》2007,31(3):236-255
Recent natural and human-induced emergencies have highlighted the vulnerability of the built environment. Although most emergency events are not entirely unexpected, and the effects can be mitigated, emergency managers in the United Kingdom have not played a sufficiently proactive role in the mitigation of such events. If a resilient and sustainable built environment is to be achieved, emergency management should be more proactive and receive greater input from the stakeholders responsible for the planning, design, construction and operation of the built environment. This paper highlights the need for emergency management to take a more systematic approach to hazard mitigation by integrating more with professions from the construction sector. In particular, design changes may have to be considered, critical infrastructures must be protected, planning policies should be reviewed, and resilient and sustainable agendas adopted by all stakeholders.  相似文献   
880.
民勤地区大震、古地理和沙尘暴的关系   总被引:3,自引:0,他引:3  
吴瑾冰 《灾害学》2004,19(2):64-68
民勤地区是中国沙尘暴发生年频次最高的地区。本文讨论了干旱、地震、古湖泊和风线对民勤地区沙尘暴形成所产生的综合作用。强地震破坏了土壤颗粒的团聚性,古湖泊环境提供了沙土混杂的地表层,风线决定了沙尘暴的飞扬和运移。  相似文献   
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