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821.
城市雨水径流污染控制技术   总被引:4,自引:0,他引:4  
城市雨水径流特别是初期雨水污染严重,是水体富营养化、水华以及海域赤潮等环境问题产生的根源之一.分析了径流污染产生的特点,概括了城市雨水径流污染控制的必要性,并着重论述了径流污染控制技术.  相似文献   
822.
介绍了四川省乐山市茫溪河流域的概况,对该流域水环境污染现状进行分析和评价,同时在对流域污染源调查的基础上得出流域的主要污染为城镇生活污染源.计算了茫溪河的水环境容量,并据此提出水污染总量控制方案.并根据茫溪河流域污染源的实际情况,针对城镇生活污染源、面源和工业污染源的不同特点提出具体的防治对策.  相似文献   
823.
高压脉冲放电等离子体水处理中的放电方式及其应用   总被引:2,自引:0,他引:2  
介绍了高压脉冲放电水处理技术的原理,综述了已有的放电方式,包括气相放电、液相放电和气液混合放电3种方式,介绍了近年来国内外对各放电方式的应用。讨论了各放电方式的特点,并提出该领域有待进行的研究工作。  相似文献   
824.
随着黄岛区迅速成为青岛市新的经济重心,该区淡水资源的紧缺与经济发展的矛盾日益突出.解决该地区水资源紧缺问题除传统的通过挖潜当地水资源及外部调水途径外,加大对海水的利用及对中水利用也是解决该区水资源紧缺问题的重要途径.结合黄岛区分区规划对黄岛区在海水利用及中水回用方面的必要性和可行性进行了探讨.  相似文献   
825.
梅雨期持续性强降水是江淮地区重要的灾害天气,往往给降水地区带来巨大的生命与经济损失。2016年7月1—7日,南京地区经历了一场历时7 d的典型梅雨降雨过程,本文针对此次降水事件的大气水汽稳定同位素变化特征及其成因进行相关研究。研究发现:水汽稳定同位素的变化特征与大尺度有组织对流活动和大气环流有良好的对应关系。水汽稳定同位素随时间分别呈现δ18O的“U型”演化和过量氘的波动变化,二者在不同降雨阶段的演化特征可以指示产生降雨的天气系统的移动与切换,其中水汽过量氘随时间变化的极大值和极小值转折点分别反映了低涡系统开始与结束影响研究区、冷切变线消散、槽线过境以及台风外围水汽抵达研究区的时间。结果表明:多个天气系统连续作用于研究区及其带来的不同水汽源的持续供给,是此次梅雨期降水持续维持的重要条件。  相似文献   
826.
选用经过十六烷三甲基溴化铵(HDTMA-Br)改性的粘土矿物为吸附剂,探讨其对水中多环芳烃类有机污染物的吸附性能。结果表明,HDTMA改性土吸附固定水中多环芳烃的能力比天然沉积物要高得多且吸附稳定。本文还讨论了环境温度、pH值、盐度、振荡时间、污染物初始浓度以及投土量对吸附性能的影响以确定吸附的适宜条件。根据实验结论,将HDTMA改性土投到实际间隙水样品中,经过充分的吸附,结果显示,经HDTMA改性粘土吸附后的间隙水中多环芳烃的含量均在检出线以下,说明HDTMA改性土可以有效地吸附固定沉积物间隙水中的多环芳烃,降低其迁移性,防止其释放产生二次污染。  相似文献   
827.
为提高煤矿防治水管理水平,预防和消除矿井水害,在层次分析法的基础上建立中性值作为参照对象对矿井水害风险进行实时评判的方法。根据《煤矿防治水细则》建立以矿井水文地质类型、矿井涌水量标准分数、突水预兆、采掘面位置、探水结果为准则层的层次结构模型,并对各评价指标赋权。依据制定的水害风险评价指标的评分细则和监测监控数据并结合其权重得到水害评价总得分。通过总得分与中性参照分数比较得出预测结果:水害评价总得分大于中性参照分数,证明水害的威胁小,分数越高越安全;反之则水害的威胁较大,分数越低越危险,这时需要加强防治水的力度,令评价分数管控大于中性参照分数。这种方法依赖于井下监测监控数据进行量化评价,能实时、客观、全面且准确地反映煤矿水害的风险情况。  相似文献   
828.
A statistical procedure is developed to adjust natural streamflows simulated by dynamical models in downstream reaches, to account for anthropogenic impairments to flow that are not considered in the model. The resulting normalized downstream flows are appropriate for use in assessments of future anthropogenically impaired flows in downstream reaches. The normalization is applied to assess the potential effects of climate change on future water availability on the Rio Grande at a gage just above the major storage reservoir on the river. Model‐simulated streamflow values were normalized using a statistical parameterization based on two constants that relate observed and simulated flows over a 50‐year historical baseline period (1964–2013). The first normalization constant is a ratio of the means, and the second constant is the ratio of interannual standard deviations between annual gaged and simulated flows. This procedure forces the gaged and simulated flows to have the same mean and variance over the baseline period. The normalization constants can be kept fixed for future flows, which effectively assumes that upstream water management does not change in the future, or projected management changes can be parameterized by adjusting the constants. At the gage considered in this study, the effect of the normalization is to reduce simulated historical flow values by an average of 72% over an ensemble of simulations, indicative of the large fraction of natural flow diverted from the river upstream from the gage. A weak tendency for declining flow emerges upon averaging over a large ensemble, with tremendous variability among the simulations. By the end of the 21st Century the higher‐emission scenarios show more pronounced declines in streamflow.  相似文献   
829.
Devils Lake is a terminal lake located in northeast North Dakota. Because of its glacial origin and accumulated salts from evaporation, the lake has a high concentration of sulfate compared to the surrounding water bodies. From 1993 to 2011, Devils Lake water levels rose by ~10 m, which flooded surrounding communities and increased the chance of an overspill to the Sheyenne River. To control the flooding, the State of North Dakota constructed two outlets to pump the lake water to the river. However, the pumped water has raised concerns about of water quality degradation and potential flooding risk of the Sheyenne River. To investigate these perceived impacts, a Soil and Water Assessment Tool (SWAT) model was developed for the Sheyenne River and it was linked to a coupled SWAT and CE‐QUAL‐W2 model that was developed for Devils Lake in a previous study. While the current outlet schedule has attempted to maintain the total river discharge within the confines of a two‐year flood (36 m3/s), our simulation from 2012 to 2018 revealed that the diversion increased the Sheyenne River sulfate concentration from an average of 125 to >750 mg/L. Furthermore, a conceptual optimization model was developed with a goal of better preserving the water quality of the Sheyenne River while effectively mitigating the flooding of Devils Lake. The optimal solution provides a “win–win” outlet management that maintains the efficiency of the outlets while reducing the Sheyenne River sulfate concentration to ≤600 mg/L.  相似文献   
830.
Weather variability has the potential to influence municipal water use, particularly in dry regions such as the western United States (U.S.). Outdoor water use can account for more than half of annual household water use and may be particularly responsive to weather, but little is known about how the expected magnitude of these responses varies across the U.S. This nationwide study identified the response of municipal water use to monthly weather (i.e., temperature, precipitation, evapotranspiration [ET]) using monthly water deliveries for 229 cities in the contiguous U.S. Using city‐specific multiple regression and region‐specific models with city fixed effects, we investigated what portion of the variability in municipal water use was explained by weather across cities, and also estimated responses to weather across seasons and climate regions. Our findings indicated municipal water use was generally well‐explained by weather, with median adjusted R2 ranging from 63% to 95% across climate regions. Weather was more predictive of water use in dry climates compared to wet, and temperature had more explanatory power than precipitation or ET. In response to a 1°C increase in monthly maximum temperature, municipal water use was shown to increase by 3.2% and 3.9% in dry cities in winter and summer, respectively, with smaller changes in wet cities. Quantifying these responses allows urban water managers to plan for weather‐driven variability in water use.  相似文献   
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