全文获取类型
收费全文 | 270篇 |
免费 | 5篇 |
专业分类
安全科学 | 4篇 |
废物处理 | 3篇 |
环保管理 | 20篇 |
综合类 | 55篇 |
基础理论 | 98篇 |
污染及防治 | 75篇 |
评价与监测 | 9篇 |
社会与环境 | 10篇 |
灾害及防治 | 1篇 |
出版年
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 3篇 |
2015年 | 7篇 |
2014年 | 5篇 |
2013年 | 13篇 |
2012年 | 7篇 |
2011年 | 12篇 |
2010年 | 6篇 |
2009年 | 13篇 |
2008年 | 7篇 |
2007年 | 19篇 |
2006年 | 6篇 |
2005年 | 9篇 |
2004年 | 2篇 |
2003年 | 9篇 |
2002年 | 9篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 19篇 |
1998年 | 12篇 |
1997年 | 13篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1981年 | 2篇 |
1978年 | 3篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1965年 | 2篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1959年 | 2篇 |
1958年 | 1篇 |
1957年 | 1篇 |
1940年 | 2篇 |
1937年 | 2篇 |
1934年 | 1篇 |
1932年 | 1篇 |
1931年 | 1篇 |
排序方式: 共有275条查询结果,搜索用时 406 毫秒
61.
62.
Rainer Haas 《Environmental Sciences Europe》1997,9(3):123-124
Diphenylarsenic chloride (CLARK I) and diphenylarsenic cyanide (CLARK II) react quickly and quantitatively with dimercaptanes at room temperature to yield diphenylarsine thiolthioether. The thiolthioethers could be identified using mass spectrometry. This reaction can be used for the gas-chromatographic detection of diphenylarsenic compounds. 相似文献
63.
Verdonck FA Boeije G Vandenberghe V Comber M de Wolf W Feijtel T Holt M Koch V Lecloux A Siebel-Sauer A Vanrolleghem PA 《Chemosphere》2005,58(9):1169-1176
Within the context and scope of the forthcoming European Union chemical regulations (REACH), there is a need to be able to prioritise the chemicals for evaluation. Therefore, a simple, pragmatic and adequately conservative approach for the identification of substances of very low or no immediate concern at an early stage is presented. The fundamental principles and basic concepts are derived from the EU Technical Guidance Document and EUSES, and are translated into an easy-to-use rule-based system. For this development, the effect on risk characterisation ratios (RCRs) of the key environmental parameters in EUSES was quantified (taking into account several standardised chemical release scenarios). Using statistical analysis, ranges were identified for each key parameter, within which the end result of the assessment was not significantly affected. This information was then translated into a lookup table from which environmental risk characterisation ratios can be directly read as a function of a few parameters. 相似文献
64.
Holocene biomass burning and global dynamics of the carbon cycle 总被引:10,自引:0,他引:10
Carcaillet C Almquist H Asnong H Bradshaw RH Carrión JS Gaillard MJ Gajewski K Haas JN Haberle SG Hadorn P Müller SD Richard PJ Richoz I Rösch M Sánchez Goñi MF von Stedingk H Stevenson AC Talon B Tardy C Tinner W Tryterud E Wick L Willis KJ 《Chemosphere》2002,49(8):845-863
Fire regimes have changed during the Holocene due to changes in climate, vegetation, and in human practices. Here, we hypothesise that changes in fire regime may have affected the global CO2 concentration in the atmosphere through the Holocene. Our data are based on quantitative reconstructions of biomass burning deduced from stratified charcoal records from Europe, and South-, Central- and North America, and Oceania to test the fire-carbon release hypothesis. In Europe the significant increase of fire activity is dated approximately 6000 cal. yr ago. In north-eastern North America burning activity was greatest before 7500 years ago, very low between 7500-3000 years, and has been increasing since 3000 years ago. In tropical America, the pattern is more complex and apparently latitudinally zonal. Maximum burning occurred in the southern Amazon basin and in Central America during the middle Holocene, and during the last 2000 years in the northern Amazon basin. In Oceania, biomass burning has decreased since a maximum 5000 years ago. Biomass burning has broadly increased in the Northern and Southern hemispheres throughout the second half of the Holocene associated with changes in climate and human practices. Global fire indices parallel the increase of atmospheric CO2 concentration recorded in Antarctic ice cores. Future issues on carbon dynamics relatively to biomass burning are discussed to improve the quantitative reconstructions. 相似文献
65.
Rainer Haas Alfred Krippendorf und Klaus Steinbach 《Umweltwissenschaften und Schadstoff-Forschung》1997,9(5):243-244
Zusammenfassung Phenylarsindichlorid (PFIFFIKUS) reagiert bei Raumtemperatur in einer Gleichgewichtsreaktion schnell mit Alkoholen unter Bildung
von Phenylarsinbisether und Phenylarsinchloridether. Die Reaktionen verlaufen nicht quantitativ. Die Derivate wurden massenspektrometrisch
identifiziert.
相似文献
66.
Volker W. J. H. Kirchhoff 《Environmental science and pollution research international》1996,3(4):210-212
Increasing carbon monoxide and ozone concentrations have been observed in the lower troposphere of the Brazilian Amazon region in recent years (1989–1995). Carbon monoxide and ozone have been measured in the region continuously; from observations at a single site and many sporadic field missions, there is a clear indication that the chemical activity in the troposphere is growing, with increasing concentrations especially during the dry season. On the other hand, the most recent deforestation assessment by the Brazilian Government, performed by the Instituto Nacional de Pesquisas Espaciais (INPE) using Landsat data, shows yearly rates rising from the 11,130 km2 year?1 minimum of the 1990/91 survey, to 13,786 km2 year?1 for the 1991/92 period, and 14,896 km2 year?1 for the period 1992/94. It is argued that the increase in deforestation/biomass burning activities in “Amazonia” have produced larger carbon monoxide and ozone concentrations in the lower atmosphere. 相似文献
67.
68.
Road development, housing growth, and landscape fragmentation in northern Wisconsin: 1937-1999. 总被引:4,自引:0,他引:4
Todd J Hawbaker Volker C Radeloff Murray K Clayton Roger B Hammer Charlotte E Gonzalez-Abraham 《Ecological applications》2006,16(3):1222-1237
Roads remove habitat, alter adjacent areas, and interrupt and redirect ecological flows. They subdivide wildlife populations, foster invasive species spread, change the hydrologic network, and increase human use of adjacent areas. At broad scales, these impacts cumulate and define landscape patterns. The goal of this study was to improve our understanding of the dynamics of road networks over time, and their effects on landscape patterns, and identify significant relationships between road changes and other land-use changes. We mapped roads from aerial photographs from five dates between 1937 and 1999 in 17 townships in predominantly forested landscapes in northern Wisconsin, U.S.A. Patch-level landscape metrics were calculated on terrestrial area outside of a 15-m road-effect zone. We used generalized least-squares regression models to relate changes in road density and landscape pattern to concurrent changes in housing density. Rates of change and relationships were compared among three ecological regions. Our results showed substantial increases in both road density and landscape fragmentation during the study period. Road density more than doubled, and median, mean, and largest patch size were reduced by a factor of four, while patch shape became more regular. Increases in road density varied significantly among ecological subsections and were positively related to increases in housing density. Fragmentation was largely driven by increases in road density, but housing density had a significantly positive relationship with largest patch area and patch shape. Without protection of roadless areas, our results suggest road development is likely to continue in the future, even in areas where road construction is constrained by the physical environment. Recognizing the dynamic nature of road networks is important for understanding and predicting their ecological impacts over time and understanding where other types of development are likely to occur in the future. Historical perspectives of development can provide guidance in prioritizing management efforts to defragment landscapes and mitigate the ecological impacts of past road development. 相似文献
69.
70.