全文获取类型
收费全文 | 2567篇 |
免费 | 392篇 |
国内免费 | 812篇 |
专业分类
安全科学 | 346篇 |
废物处理 | 82篇 |
环保管理 | 259篇 |
综合类 | 1788篇 |
基础理论 | 384篇 |
环境理论 | 1篇 |
污染及防治 | 468篇 |
评价与监测 | 104篇 |
社会与环境 | 155篇 |
灾害及防治 | 184篇 |
出版年
2024年 | 14篇 |
2023年 | 70篇 |
2022年 | 155篇 |
2021年 | 163篇 |
2020年 | 187篇 |
2019年 | 148篇 |
2018年 | 134篇 |
2017年 | 159篇 |
2016年 | 133篇 |
2015年 | 179篇 |
2014年 | 202篇 |
2013年 | 249篇 |
2012年 | 260篇 |
2011年 | 252篇 |
2010年 | 217篇 |
2009年 | 195篇 |
2008年 | 199篇 |
2007年 | 168篇 |
2006年 | 161篇 |
2005年 | 118篇 |
2004年 | 83篇 |
2003年 | 67篇 |
2002年 | 56篇 |
2001年 | 35篇 |
2000年 | 30篇 |
1999年 | 29篇 |
1998年 | 26篇 |
1997年 | 13篇 |
1996年 | 11篇 |
1995年 | 10篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1984年 | 4篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1962年 | 1篇 |
1961年 | 3篇 |
1959年 | 1篇 |
1932年 | 1篇 |
排序方式: 共有3771条查询结果,搜索用时 15 毫秒
611.
Zhang B Hong M Zhang B Zhang XL Zhao YS 《Environmental monitoring and assessment》2007,133(1-3):379-386
Endemic fluorosis was investigated and studied in the west region of the Songnen plain, Northeast China in 2001–2002. The
results showed that the fluorine distribution in aquatic environment was that the fluorine concentrations in the lake water
and unconfined ground water were higher than that in the river water and confined ground water. The lake water (Alkali lake)
is connected with unconfined ground water. In unconfined ground water, from the east and southeast areas to the west and the
northwest areas of the plain, fluorine concentration fluctuated with high and low alternatively. The fluorine in the water
comes from the weathering of rocks and minerals in the mountains and hills around the Songnen Plain. The main influence factors
of the fluorine distribution in aquatic environment are discussed. Unconfined ground water containing high fluorine is used
as drinking water. In this region, the fluorine concentration in drinking water is evidently correlated to the morbidity of
dental and skeletal fluorosis. High fluorine concentration in drinking water has endangered human health. 相似文献
612.
针对桑蚕污染事故的特点和监测中存在的问题,阐述了现场调查,布点采样,分析测试及结果评价等环节的技术要点和注意事项,并就与之密切相关的几个问题展开了讨论,为桑蚕污染事故的监测节一定的参考依据。 相似文献
613.
Jacobsen CS van der Keur P Iversen BV Rosenberg P Barlebo HC Torp S Vosgerau H Juhler RK Ernstsen V Rasmussen J Brinch UC Jacobsen OH 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):794-802
Pesticide mineralization and sorption were determined in 75 soil samples from 15 individually drilled holes through the vadose zone along a 28 km long transect of the Danish outwash plain. Mineralization of the phenoxyacetic acid herbicide MCPA was high both in topsoils and in most subsoils, while metribuzine and methyltriazine-amine was always low. Organic matter and soil pH was shown to be responsible for sorption of MCPA and metribuzine in the topsoils. The sorption of methyltriazine-amine in topsoil was positively correlated with clay and negatively correlated with the pH of the soil. Sorption of glyphosate was tested also high in the subsoils. One-dimensional MACRO modeling of the concentration of MCPA, metribuzine and methyltriazine-amine at 2 m depth calculated that the average concentration of MCPA and methyltriazine-amine in the groundwater was below the administrative limit of 0.1 μg/l in all tested profiles while metribuzine always exceeded the 0.1 μg/l threshold value. 相似文献
614.
Iorio M Pan B Capasso R Xing B 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):1021-1029
Intent of this study was to explore the potential application of polymerin, the polymeric, dissolved organic matter fraction from olive oil wastewaters, in technologies aimed at remediating hydrophobic organic compounds (HOCs) point-source pollution. Phenanthrene binding with polymerin was investigated. Moreover, the effect of addition of micro and nanoscale aluminum oxides (Al2O3) was studied, as well as sorption of polymerin on the oxides. Phenanthrene binding capacity by polymerin was notably higher than the sorption capacities for both types of Al2O3 particles. Polymerin sorption on nanoparticles was nearly 100 times higher than microparticles. In a three-phase system, using microparticles, higher phenanthrene sorption was found by adding into water polymerin, oxides and phenanthrene simultaneously. In contrast, using nanoparticles, a considerable enhancement of phenanthrene sorption was shown by adding phenanthrene to a pre-formed and dried polymerin-oxide complex. These findings support the application of polymerin, especially associated with Al2O3 nanoparticles, in remediation of water contaminated with HOCs. This work highlights the significant role of nanoparticles. 相似文献
615.
川中丘陵区典型小流域地下水硝酸盐污染分析 总被引:15,自引:1,他引:14
对川中丘陵区典型小流域地下水N素含量及形态分配的监测结果表明,硝酸盐(NO3--N)是该地区地下水N素存在的主要形态。川中丘陵区54.5%的地下水NO3--N含量超过世界卫生组织(WHO)饮用水准则规定的10mg.L-1标准,另有27.3%的地下水NO3--N含量接近这一标准,表明该区地下水已经大范围地受到NO3--N污染的威胁。土地利用状况可能是影响川中丘陵区地下水NO3--N含量的主要因素。降雨量和水井深度也影响该区地下水NO3--N含量。紫色土坡耕地NO3--N随壤中流向浅层地下水迁移,可能是造成该区地下水NO3--N含量较高的最重要原因。 相似文献
616.
New Metal Emission Patterns in Road Traffic Environments 总被引:10,自引:0,他引:10
The increased awareness of traffic as a major diffuse metal emission source emphasizes the need for more detailed information
on the various traffic-related sources and how and where the metals are dispersed. In this study, metal emission patterns
in the road traffic environment were examined from the perspective of different surrounding factors, e.g. the importance of
intersections, deceleration, vehicle speed and traffic density. A total of 148 topsoil samples from 18 south Swedish roads
were analysed (using GFAAS) for traffic-emitted metals, i.e. Cd, Cr, Cu, Ni, Pb, Sb and Zn. The roadside topsoil metal concentrations
were used to examine correlations between metals and surrounding factors. The studied metals were divided into three groups
corresponding to different emission sources: metals from decelerating activities (Cu, Sb and Zn), metals as historical residues
from the combustion of petrol (Pb and Cd), and non-source-specific metals (Cr and Ni). It was found that Cu and Sb, despite
their rather short history as traffic-emitted metals, have increased more than eightfold in roadside soils compared to background
levels. The major source of road traffic related Cu and Sb is brake linings. The significant increase of Cu and Sb in roadside
topsoil stresses the need for metal transport studies as well as effect studies of these metals. Metals emitted due to decelerating
activities were not correlated to elevated concentrations near road junctions. Emission patterns of traffic-related metals
alongside roads are crucial in order to be able to evaluate the optimal localization of storm water treatment ponds. 相似文献
617.
水体中重要污染元素化学形态分析研究方法及其进展 总被引:3,自引:0,他引:3
概述了元素化学形态分析的意义、概念和范围,元素化学形态分析与模拟计算方法,并分别对某些重要元素的化学形态分析方法的进展作了综述,介绍了115篇文献。 相似文献
618.
基于先进的多普勒天气雷达探测技术,直接获取多种类型的降水产品,以模糊数学为基础,利用可拓学原理,建立了多层嵌套式泥石流预报可拓模型。模型根据研究区泥石流发生条件的不同,将临界雨量划分成不同的等级范围,确定泥石流发生的概率大小。将该泥石流预报方法应用到四川省凉山州,以ArcGIS为工具开发了凉山州泥石流短临预报应用系统。当有灾害性天气过程出现时,将启动预报系统,逢整点读取降水产品信息,实现1h滚动预报,预报时段为3h。系统可及时地为政府提供全州的泥石流预报信息,为减灾防灾决策提供技术支持。 相似文献
619.
及时发现变电站内电力电缆的故障对保证变电站安全稳定运行具有重要意义。介绍了1种基于暂态零序电流法的站内电缆监测系统,对系统的监测原理和各部件参数要求进行了论述,并采用单相失压模拟试验和人工单相接地试验对电缆线路监测系统进行了验证。试验结果表明,该系统可以准确地采集电缆线路故障发生时的暂态零序电流,并能及时将故障报警信息上报运维人员,保证变电站安全稳定运行。 相似文献
620.
由于GIS设备内部存在缺陷或故障需要进行检查时,GIS罐体较长、管径细小,采用人工的方法无法有效查看内部状态并难以进入内部进行检修作业,因此本文研究了GIS设备内部检查机器人,采用模块化设计并实现了柔性机械臂功能、异物清扫功能及环境感知监测功能的模块化替换,可根据不同的作业场所选择对应的机器人功能模块进行内部工作。在实验室搭建了GIS设备罐体进行功能模块实验验证,实验结果表明:柔性机械臂模块旋转角、弯曲角满足GIS内部复杂环境作业要求,异物清扫模块能够完全清理GIS腔体底部的不同类型微小异物,环境监测感知模块可实现罐体内O2、H2S、SO2成分检测,确保机器人在110 kV及以上GIS设备内部发挥效用。 相似文献