全文获取类型
收费全文 | 17345篇 |
免费 | 137篇 |
国内免费 | 77篇 |
专业分类
安全科学 | 388篇 |
废物处理 | 697篇 |
环保管理 | 2060篇 |
综合类 | 4000篇 |
基础理论 | 3847篇 |
环境理论 | 7篇 |
污染及防治 | 4262篇 |
评价与监测 | 1145篇 |
社会与环境 | 1086篇 |
灾害及防治 | 67篇 |
出版年
2022年 | 126篇 |
2021年 | 161篇 |
2020年 | 104篇 |
2019年 | 144篇 |
2018年 | 238篇 |
2017年 | 238篇 |
2016年 | 351篇 |
2015年 | 274篇 |
2014年 | 416篇 |
2013年 | 1175篇 |
2012年 | 448篇 |
2011年 | 692篇 |
2010年 | 525篇 |
2009年 | 619篇 |
2008年 | 694篇 |
2007年 | 733篇 |
2006年 | 650篇 |
2005年 | 554篇 |
2004年 | 585篇 |
2003年 | 579篇 |
2002年 | 531篇 |
2001年 | 669篇 |
2000年 | 420篇 |
1999年 | 318篇 |
1998年 | 200篇 |
1997年 | 213篇 |
1996年 | 229篇 |
1995年 | 246篇 |
1994年 | 239篇 |
1993年 | 228篇 |
1992年 | 209篇 |
1991年 | 210篇 |
1990年 | 201篇 |
1989年 | 174篇 |
1988年 | 172篇 |
1987年 | 156篇 |
1986年 | 157篇 |
1985年 | 152篇 |
1984年 | 171篇 |
1983年 | 175篇 |
1982年 | 177篇 |
1981年 | 148篇 |
1980年 | 134篇 |
1979年 | 125篇 |
1978年 | 135篇 |
1977年 | 116篇 |
1976年 | 105篇 |
1975年 | 107篇 |
1974年 | 119篇 |
1967年 | 102篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
461.
Alessandra De Marco 《Environmental pollution (Barking, Essex : 1987)》2009,157(5):1407-1412
A review of ozone pollution in Italy shows levels largely above the thresholds established by EU regulation for vegetation and human health protection. The Italian air quality monitoring network appears quantitatively inadequate to cover all the territorial surface, because of scarcity and unequal distribution of monitoring sites. By applying the integrated assessment model RAINS-Italy to the year 2000, the whole of Italy exceeds the AOT40 critical level for forest, while Northern and central areas show strong potential of O3 impact on human health with ∼11% of territory >10 O3-induced premature deaths. Two scenarios for the year 2020, the Current Legislation and the Maximum Technical Feasible Reduction, show a reduction of AOT40Forest by 29% and 44%, SOMO35 by 31% and 47%, and O3-induced premature deaths by 32% and 48%, compared to 2000. RAINS-Italy can be used to improve the map quality and cover areas not reached by the national monitoring network. 相似文献
462.
G J Mohanrao P V Subrahmanyam S B Deshmukh S Saroja 《Journal - Water Pollution Control Federation》1970,42(8):1530-1543
463.
464.
The sampling procedure of solid and gaseous pollutants, contained in flue gas emitted into the atmosphere by solid waste incinerating furnaces were investigated. Because of their extraordinary toxicological properties, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are taken into particular consideration. The analytical work is based on the use of high-resolution gas chromatography in combination with low-resolution mass spectrometry. Details of the extensive sample clean-up will follow the GC-MS separation and identification of the isomers detected for each group of PCDDs and PCDFs. Quantitative data of these pollutants distribution levels deriving from different investigated incinerators are also reported. 相似文献
465.
Boxman AW Peters RC Roelofs JG 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):1252-1259
In a Scots pine forest the throughfall deposition and the chemical composition of the soil solution was monitored since 1984. (Inter)national legislation measures led to a reduction of the deposition of nitrogen and sulphur. The deposition of sulphur has decreased by approximately 65%. The total mineral-nitrogen deposition has decreased by ca. 25%, which is mainly due to a reduction in ammonium-N deposition (−40%), since nitrate-N deposition has increased (+50%). The nitrogen concentration in the upper mineral soil solution at 10 cm depth has decreased, leading to an improved nutritional balance, which may result in improved tree vitality. In the drainage water at 90 cm depth the fluxes of NO3− and SO42− have decreased, resulting in a reduced leeching of accompanying base cations, thus preserving nutrients in the ecosystem. It may take still several years, however, before this will meet the prerequisite of a sustainable ecosystem. 相似文献
466.
467.
468.
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
469.
470.
Grodzińska K Szarek-Łukaszewska G 《Environmental pollution (Barking, Essex : 1987)》2001,114(3):443-451
Concentrations of heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, Zn) in Pleurozium schreberi (Brid.) Mitt., a common moss species, were used to indicate relative levels of atmospheric deposition in Poland in the years 1975-1998. Spatial and temporal differences in the heavy metal concentrations in mosses were found. The highest concentration of heavy metals was recorded in the moss samples from the southern, most industrialised part of the country, and the lowest from north-eastern Poland. A significant decrease of heavy metals over 20 years (1975-1998) was found. 相似文献