全文获取类型
收费全文 | 20333篇 |
免费 | 181篇 |
国内免费 | 201篇 |
专业分类
安全科学 | 534篇 |
废物处理 | 986篇 |
环保管理 | 2418篇 |
综合类 | 2667篇 |
基础理论 | 5284篇 |
环境理论 | 4篇 |
污染及防治 | 5597篇 |
评价与监测 | 1650篇 |
社会与环境 | 1453篇 |
灾害及防治 | 122篇 |
出版年
2023年 | 92篇 |
2022年 | 215篇 |
2021年 | 217篇 |
2020年 | 139篇 |
2019年 | 177篇 |
2018年 | 326篇 |
2017年 | 320篇 |
2016年 | 524篇 |
2015年 | 362篇 |
2014年 | 573篇 |
2013年 | 1744篇 |
2012年 | 672篇 |
2011年 | 859篇 |
2010年 | 802篇 |
2009年 | 785篇 |
2008年 | 886篇 |
2007年 | 976篇 |
2006年 | 870篇 |
2005年 | 716篇 |
2004年 | 723篇 |
2003年 | 704篇 |
2002年 | 670篇 |
2001年 | 911篇 |
2000年 | 631篇 |
1999年 | 393篇 |
1998年 | 274篇 |
1997年 | 246篇 |
1996年 | 291篇 |
1995年 | 270篇 |
1994年 | 250篇 |
1993年 | 233篇 |
1992年 | 240篇 |
1991年 | 208篇 |
1990年 | 214篇 |
1989年 | 219篇 |
1988年 | 197篇 |
1987年 | 158篇 |
1986年 | 126篇 |
1985年 | 138篇 |
1984年 | 169篇 |
1983年 | 153篇 |
1982年 | 193篇 |
1981年 | 134篇 |
1980年 | 119篇 |
1979年 | 152篇 |
1978年 | 118篇 |
1977年 | 107篇 |
1976年 | 100篇 |
1975年 | 83篇 |
1974年 | 88篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
501.
502.
Pollution indicators and other microorganisms in river sediment 总被引:12,自引:0,他引:12
503.
Persistence of residues in water and sediment of a fresh-water lake after surface application of technical chlordane 总被引:1,自引:0,他引:1
P C Oloffs L J Albright S Y Szeto 《Journal of environmental science and health. Part. B》1978,13(1):47-58
A fresh-water lake, free from detectable pesticide residues before this study, was treated with a commercial formulation of technical chlordane. Water and sediment samples were analysed for chlordane residues 7, 24, 52, 279. and 421 days after treatment. Residues moved rapidly from the water to the lake bottom, supporting earlier results of a laboratory study with other organochlorines. In water, alpha- and gamma-chlordane concentrations remained proportional to total chlordane concentrations, as determined by total-peak area measurements of gas-liquid chromatogrammes. But in bottom sediments, alpha- and gamma-chlordane were more persistent than other constituents of technical chlordane, supporting recent evidence that quantification of technical chlordane residues on the basis of gamma-chlordane quantification only (or that of alpha- and gamma-chlordane only), can lead to incorrect results and that this method, although simple and fast, should no longer be recommended. 相似文献
504.
505.
506.
507.
508.
D. Luján-Rhenals Z. Shi S. C. Ricke 《Journal of environmental science and health. Part. B》2018,53(1):12-17
Soybean meal (SBM) is a product generated from the manufacture of soybean oil and has the potential for use as a source of fermentable sugars for ethanol production or as a protein source for animal feeds. Knowing the levels of nitrogen available from ammonium is a necessary element of the ethanolic fermentation process while identifying the levels of essential amino acids such as lysine is important in determining usage as a feed source. As such the purpose of this study was to quantify total nitrogen and ammonium in the liquid fraction of hydrolyzed SBM and to evaluate total and bioavailable lysine in the solid fraction of the hydrolyzed SBM. The effects of acid concentration, cellulase and β-glucosidase on total and ammonium nitrogen were studied with analysis indicating that higher acid concentrations increased nitrogen compounds with ammonium concentrations ranging from 0.20 to 1.24 g L?1 while enzymatic treatments did not significantly increase nitrogen levels. Total and bioavailable lysine was quantified by use of an auxotrophic gfpmut3 E.coli whole-cell bioassay organism incapable of lysine biosynthesis. Acid and enzymatic treatments were applied with lysine bioavailability increasing from a base of 82% for untreated SBM to up to 97%. Our results demonstrated that SBM has the potential to serve in ethanolic fermentation and as an optimal source essential amino acid lysine. 相似文献
509.
510.
Charlotte R. Dromard Mathilde Guéné Yolande Bouchon-Navaro Soazig Lemoine Sébastien Cordonnier Claude Bouchon 《Environmental science and pollution research international》2018,25(15):14294-14301
Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. The objective of the present study is to evaluate the level of contamination in several trophic groups of marine animals according to their distance from the source of pollution. Samples of suspended matter, macroalgae, herbivorous fishes, detrivorous crustaceans, zooplanktivorous fishes, first- and second-order of carnivorous fishes, and piscivorous fishes have been collected in two sites, located downstream the contaminated sites (Goyave and Petit-Bourg), in three marine habitats (coastal mangroves, seagrass beds located 1.5 km from the shoreline, and coral reefs at 3 km offshore). Animals collected in mangroves were the most contaminated (mean concentrations 193 μg kg?1 in Goyave and 213 μg kg?1 in Petit-Bourg). Samples from seagrass beds presented intermediate concentrations of chlordecone (85 μg kg?1 in Goyave and 107 μg kg?1 in Petit-Bourg). Finally, samples from coral reefs were the less contaminated (71 μg kg?1 in Goyave and 74 μg kg?1 in Petit-Bourg). Reef samples, collected 3 km offshore, were two to three times less contaminated than those collected in mangroves. 相似文献