全文获取类型
收费全文 | 724篇 |
免费 | 65篇 |
国内免费 | 398篇 |
专业分类
安全科学 | 15篇 |
废物处理 | 49篇 |
环保管理 | 41篇 |
综合类 | 655篇 |
基础理论 | 183篇 |
污染及防治 | 121篇 |
评价与监测 | 105篇 |
社会与环境 | 17篇 |
灾害及防治 | 1篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 32篇 |
2021年 | 19篇 |
2020年 | 16篇 |
2019年 | 36篇 |
2018年 | 37篇 |
2017年 | 44篇 |
2016年 | 61篇 |
2015年 | 65篇 |
2014年 | 84篇 |
2013年 | 113篇 |
2012年 | 70篇 |
2011年 | 49篇 |
2010年 | 67篇 |
2009年 | 46篇 |
2008年 | 44篇 |
2007年 | 59篇 |
2006年 | 49篇 |
2005年 | 52篇 |
2004年 | 47篇 |
2003年 | 25篇 |
2002年 | 18篇 |
2001年 | 35篇 |
2000年 | 30篇 |
1999年 | 12篇 |
1998年 | 11篇 |
1997年 | 17篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 8篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
排序方式: 共有1187条查询结果,搜索用时 218 毫秒
781.
Böhme F Rinklebe J Stärk HJ Wennrich R Mothes S Neue HU 《Environmental science and pollution research international》2005,12(3):133-135
Background Estimations of gaseous mercury volatilization from soils are often complex, stationary and expensive. Our objective was to develop a mobile and more simple, easy to handle and more cost-effective field method allowing rapid estimates of potential Hg emissions from soils.
Methods. The study site is located in Germany, about 100 kilometers south-westerly of Berlin and influenced by the river Elbe and its tributary Saale river. The site is representative for a lot of other floodplain locations at the river Elbe and highly polluted with Hg and other heavy metals. For our study we developed a system consisting of a glass chamber gas, two gold traps, a battery operated pump and a gas meter. Adsorbed total gaseous mercury (TGM) in the gold traps was determined by use of atomic absorption spectrometry (AAS).
Results and Discussion. In contrast to the common used flux chambers we designed a chamber without inlet and named it gas suck up chamber (GSC). TGM fluxes determined with the GSC showed a very close linear correlation (r = 0.993) between the TGM content in the gold traps and the corresponding pumped gas volume. The TGM adsorbed, increased proportional with increasing gas volume indicating homogenous concentrations of gaseous mercury in the soil air sucked. In contrast to the commonly used dynamic flux chamber with the aim of precisely measuring actual fluxes of Hg from a defined soil area, we focused on developing of a measurement system which will allow rapid estimates of potential Hg emissions of a site. Earlier research at the study site indicated a high potential for releasing volatile Hg from the soil to the atmosphere. Indeed, due to the high Hg content of the soil significant amounts of TGM could be detected and no shortage was reached.
Conclusion. Our initial measurements are still too few in number neither to generalize the achieved results nor discuss controlling factors and processes. However, we are pleased to communicate that the developed GSC is well suited to become an effective sampling set up to rapidly estimate the magnitude of Hg volatilization from soils.
Outlook. Further measurements at other polluted locations are necessary to verify the GSC method. In addition the use of a mercury analyzer instead of gold traps is planned for faster risk assessments. 相似文献
782.
783.
Accumulation of Hg(II) by microbial biofilms on suspended particulate matter 相似文献
784.
785.
786.
787.
研究了GaAs、Ga~(3+)、Ge~(4+)、Hg~(2+)和Cr~(6+)对活性污泥脱氧核糖核酸(DNA)和核糖核酸(RNA)的影响,以及GaAs对活性污泥氨基酸的影响。结果表明,Hg~(2+)和Cr~(6+)主要使活性污泥中核酸的DNA含量减少,GaAs则主要使RNA含量减少,Ge~(4+)浓度达到300ppm/g MLSS对,无论对DNA还是RNA的合成都有较强的抑制影响。低浓度的GaAs对活性污泥氨基酸含量影响不大,而GaAs浓度达360ppm/g MLSS时则使活性污泥中氨基酸含量明显减少。 相似文献
788.
本文在数字化地下流体化学组分的观测中,认为热水井的脱气和脱气后的气体干燥是两个关键环节。我们在怀4井的气汞观测中,经过多次试验改进较好地解决了这两个环节。2004年以来,观测资料稳定,并清晰地记录到了固体潮形态。 相似文献
789.
IntroductionRecognitionofmercuryasatrans nationalboundarypollutantandthediscoveryofthenegativecorrelationbetweenfishmercurylevelsandwaterpHanditsimplicationwithregardtoacidrainhavegeneratedalotofinterestinscientificresearchonenvironmentalmercuryconta… 相似文献
790.
汞的地球化学行为取决于汞的物理化学性质.汞在地震活动过程中的异常变化十分明显,映震效能较好。通过分析主要震例发现,汞异常特征普遍表现为高值或正脉冲及其脉冲群。异常分布范围与震级大小有关。一般来说是在异常结束后发震,但也有的是在高值段或异常恢复段发震。异常一般出现于震前几天到几个月不等。 相似文献