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   701篇
  免费   54篇
  国内免费   223篇
安全科学   49篇
废物处理   32篇
环保管理   77篇
综合类   389篇
基础理论   127篇
污染及防治   202篇
评价与监测   45篇
社会与环境   40篇
灾害及防治   17篇
  2024年   1篇
  2023年   16篇
  2022年   35篇
  2021年   47篇
  2020年   31篇
  2019年   30篇
  2018年   32篇
  2017年   40篇
  2016年   33篇
  2015年   39篇
  2014年   49篇
  2013年   74篇
  2012年   54篇
  2011年   60篇
  2010年   53篇
  2009年   49篇
  2008年   49篇
  2007年   34篇
  2006年   46篇
  2005年   34篇
  2004年   12篇
  2003年   28篇
  2002年   27篇
  2001年   12篇
  2000年   12篇
  1999年   12篇
  1998年   7篇
  1997年   11篇
  1996年   8篇
  1995年   8篇
  1994年   7篇
  1993年   5篇
  1992年   12篇
  1991年   2篇
  1990年   1篇
  1989年   3篇
  1988年   2篇
  1987年   1篇
  1985年   1篇
  1981年   1篇
排序方式: 共有978条查询结果,搜索用时 15 毫秒
131.
建立了电感耦合等离子体质谱(ICP-MS)的八级杆碰撞/反应池(ORS)技术测定地质样品中Pt,Pd,Rh的方法.结果显示,王水溶样、微波消解,可以有效地提高Pt、Pd、Rh的溶出率.ORS技术的使用,有效地消除了多原子离子对待测元素的干扰,特别是对Pd的干扰,使Pt、Pd、Rh的测定结果准确.Pt,Pd、Rh的检出限分别为0.47ng·g-1,0.44ng·g-1,0.065n·g-1,精密度为1.11%-2.57%.此方法为复杂基体样品中贵金属元素的快速、准确分析提供了一种新的途径.  相似文献   
132.
建筑小区雨水径流的土壤渗透净化   总被引:3,自引:0,他引:3  
讨论了建筑小区雨水径流的污染性、土壤渗透对小区径流的净化作用及土壤的渗透能力,提出了建筑小区雨水径流土壤渗透的工程实施方案。  相似文献   
133.
Among the effects of global warming, sea level rise (SLR) and severe typhoons pose the greatest threat to the stability of human settlements along coastlines. Therefore, countermeasures must be developed to mitigate the influences of strong typhoons and persistent SLR for coastal protection. This study assesses climate change impacts on coastal erosion, especially in two projected SLR scenarios of RCP2.6 and RCP8.5. The results show that SLR and severe typhoons lead to the increase of coastal erosion, beach lowering and scour. Moreover, as in projected SLR scenarios, average waves in high tide can cause severe soil erosion at inner slopes and lead to dyke failure by 2060. The paper highlights the need for additional countermeasures to protect the coast of Hai Hau district against SLR and severe typhoons. Among the alternatives available for countering these threats, applying soil stabilization and soil improvement combined with geosynthetics are promising strategies for coastal structures. Hybrid structures can be used with earth reinforcement and soil improvement. Additionally, the paper emphasizes the importance of multiple protective adaptations, including geosynthetics and ecological engineering measures against climate change-induced severe erosion on the coast of Hai Hau district.  相似文献   
134.
三界谷来地区主要出露中、新生代火山岩。进行 1/5万区域地质调查时,采用火山活动旋回-火山构造-火山地层-岩相、岩性-体化思路,按照同旋回火山机构或火山喷发区为单元,确定岩石地层单位和填图单元。火山岩划分为九种岩相类型,建立了两个岩相模式和一个三相一体成因模式。根据火山岩浆作用的旋回性及其产物与火山构造形迹时、空、成因一致性原理,将中、新生代火山岩浆作用分为四个火山活动旋回,圈定了相应的火山机构或火山喷发中心,建立了竹田头复活破火山演化模式。新生代玄武岩中发现二辉斜长麻粒岩等深源包体,为研究区域深部地质作用过程提供了证据。侵入岩按岩石谱系单元划分了七个岩石单元一个超单元,将侵入岩-潜火山岩-火山岩作为岩浆作用整体研究,为正确阐明岩浆作用及其演化规律奠定了基础。区域线型构造发育,与环形火山构造组合,形成火山岩区特有的线一环构造格局。中上元古界陈蔡群变质岩划分为上、下两个岩组,探讨了变质岩的原岩性质及其形成的大地构造环境。  相似文献   
135.
宜宾市三江水体粪大肠菌群污染现状调查   总被引:3,自引:0,他引:3  
宋在兰  张兰  黄斌 《四川环境》2003,22(6):36-38
粪大肠茵群指数(FC)是综合评价城市污水,尤其是生活污水的一个重要指标。本文对宜宾市“三江”水体的FC进行了监测,结果表明“三江”受到了生活污水的污染。丰水期的FC指数超出我国地表水Ⅲ类标准的10倍。  相似文献   
136.
This paper reviewed recent research in environmental governance as a response to environmental challenges at various spatial, temporal and administrative scales. It documented the shift of approach from regulation to governance, and attempted to provide a comprehensive understanding why and how the transformation occurred. It also described major factors and forces of environmental governance, and discussed research advance in environmental governance theory. Finally, this paper summarized recent research findings on environmental governance in China, and listed policy recommendation for enhancing the governance.  相似文献   
137.
浙江墩头盆地横山组孢粉化石的发现及其地层意义   总被引:1,自引:0,他引:1  
浙江墩头盆地红色岩层中上部首获丰富的以Cassopllis为主(58.39—62.54%)伴有Exesipollenites(15.21—15.84%),Hsuisporites(0.56—0.62%),Cicatricosisporites(0—0.31%)等孢粉化石。该孢粉组合特征既与国内外晚侏罗世孢粉组合面貌差别较大,又与早白垩世中晚期孢粉组合面貌存在明显差异,显示了早白垩世早期孢粉组合的色彩。笔者认为这套红色岩层应归早白垩世早期横山组为宜。  相似文献   
138.
环境影响评价中的公众参与现状及其改进建议   总被引:5,自引:0,他引:5  
通过对30多份环境影响报告书的分析,针对我国目前的公众参与现状及存在的问题,提出改进建议。  相似文献   
139.
Supercritical fluid extraction (SFE) is a rapid and convenient method for the isolation of organic compounds from environmental samples. This paper describes a supercritical carbon dioxide (CO2) extraction system that uses a newly designed extraction cell to recover organic compounds from an aqueous matrix. Analysis of the extracts by gas chromatography-electron capture detector (GC-ECD) indicated that the herbicide trifluralin (2,6-dinitro-N,N-dipropyl-4-trifluoromethylaniline) could be quantitatively extracted by using the SFE system proposed with small amounts of sample. The percentage of recovery obtained with the SFE system described was twice as high as the result obtained using a conventional solid-phase extraction technique. Extraction by SFE was completed in a short period of time using a simple and low-cost home-made system that did not require the use of organic solvents.  相似文献   
140.
Coagulation plays an important role in alleviating membrane fouling, and a noticeable problem is the development of microorganisms after long-time operation, which gradually secrete extracellular polymeric substances(EPS). To date, few studies have paid attention to the behavior of microorganisms in drinking water treatment with ultrafiltration(UF)membranes. Herein, the membrane biofouling was investigated with different aluminum and iron salts. We found that Al_2(SO_4)_3·18 H_2O performed better in reducing membrane fouling due to the slower growth rate of microorganisms. In comparison to Al_2(SO_4)_3·18H_2O,more EPS were induced with Fe_2(SO_4)_3·x18H_2O, both in the membrane tank and the sludge on the cake layer. We also found that bacteria were the major microorganisms, of which the concentration was much higher than those of fungi and archaea. Further analyses showed that Proteobacteria was dominant in bacterial communities, which caused severe membrane fouling by forming a biofilm, especially for Fe_2(SO_4)_3·x18H_2O. Additionally, the abundances of Bacteroidetes and Verrucomicrobia were relatively higher in the presence of Al_2(SO_4)_3·18 H_2O,resulting in less severe biofouling by effectively degrading the protein and polysaccharide in EPS. As a result, in terms of microorganism behaviors, Al-based salts should be given preference as coagulants during actual operations.  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