全文获取类型
收费全文 | 91篇 |
免费 | 0篇 |
专业分类
废物处理 | 1篇 |
环保管理 | 1篇 |
综合类 | 16篇 |
基础理论 | 35篇 |
污染及防治 | 34篇 |
评价与监测 | 2篇 |
社会与环境 | 2篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2018年 | 2篇 |
2013年 | 7篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 1篇 |
2007年 | 3篇 |
2006年 | 4篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1994年 | 4篇 |
1992年 | 5篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1967年 | 1篇 |
1965年 | 1篇 |
1964年 | 1篇 |
1958年 | 1篇 |
1957年 | 2篇 |
1955年 | 1篇 |
1954年 | 2篇 |
排序方式: 共有91条查询结果,搜索用时 234 毫秒
41.
42.
Many chemicals are in common commercial use for which no information on the environmental fate or toxicity exists. Recent legislation requires that many substances be assessed for their toxicity to aquatic organisms within a very short time and determine which of these chemicals need to be studied in greater detail. It would be impossible to measure the acute and chronic effects of all of these compounds on a single organism, let alone a battery of different types of organisms, communities or ecosystems. Initially, the chemicals on the European Inventory of Existing Commercial Chemical Substances (EINECS) need to be screened and relative hazard to the environment determined. In response to OECD directives, there has been a great deal of activity by government and industry scientists. At the International Workshop on Advances in Environmental Hazard and Risk Assessment it was concluded that quantitative structure activity relationships (QSAR) could and should be used in the hazard assessment process. Papers published in that volume outline the advantages, disadvantages, limitations, advances and research requirements. The QSAR, structure‐activity based chemical modeling and information system, which was developed by the US‐Environmental Protection Agency was used to predict the acute toxicity of 113 substances from the “Old Substances”; list of the German government to the four commonly used aquatic toxicity test organisms: Daphnia magna (DM), fathead minnow (FHM), rainbow trout (RBT), and blue‐gill sunfish (BG). Of these compounds the QSAR system predicted the acute toxicity of 87 substances towards fathead minnow. For the other three species examined the QSAR system could be used to predict toxicity for 78 compounds. The predicted toxicities were compared to observed toxicities of compounds which have been evaluated and stored in the “Aquire”; data base. Observed toxicity values were available for at least one species for 38 compounds. The toxicities of some compounds are well predicted while those of other compounds were not well predicted. Overall, the QSAR system accurately classified the acute toxicity ranges of 50%, 64%, 56% and 56% of the compounds investigated for DM, FHM, RBT and BG, respectively. Of the compounds studied 10 were very poorly predicted, of these the QSAR system overpredicted the toxicity of three, while underpredicting the toxicity of seven. Of these seven compounds, five contained amino groups. 相似文献
43.
Yuan Meng Weiyi Liu Heidelore Fiedler Jinlan Zhang Xinrui Wei Xiaohui Liu Meng Peng Tingting Zhang 《Frontiers of Environmental Science & Engineering》2021,15(5):104
44.
45.
46.
Kleineidam K Košmrlj K Kublik S Palmer I Pfab H Ruser R Fiedler S Schloter M 《Chemosphere》2011,84(1):182-186
In agricultural plant production nitrification inhibitors like 3,4-dimethylpyrazole phosphate (DMPP) are used to retard the microbial nitrification process of fertilized ammonium to enhance the nitrogen supply for cultivated crops and to reduce nitrogen losses from the production system. Besides the well-known ammonia-oxidizing bacteria (AOB) it is known for a few years that also ammonia-oxidizing archaea (AOA) are able to perform the first step in nitrification, hence being also a target for a nitrification inhibitor. However, so far no information are available concerning the effectiveness of DMPP and its extent towards AOB and AOA, neither in bulk soil nor in the root-rhizosphere complex. We investigated in a field experiment performed according to agricultural practice the effect of DMPP on the abundance of AOB and AOA two, four and eight weeks after fertilization. We observed impaired abundances of AOB but not of AOA in both soil compartments that were still visible eight weeks after application, possibly indicating a reduced effectiveness of the nitrification inhibitor in our study. 相似文献
47.
Concentrations of technical 4-nonylphenol, 4-n-octylphenol, and 4-tert-octylphenol were investigated in surface water and sediment samples of four reservoirs southwest of S?o Paulo. Three of them (Takimoto 1, Takimoto 2, Pedro) were established in intensively cropped landscapes, one (Morro Grande) was surrounded by dense forests. Total alkylphenol concentrations in sediments generally ranged between 1 and 10 microgkg-1dw with 4-tert-octylphenol being the dominant alkylphenol. Because 4-tert-octylphenol concentration patterns at Takimoto 2, Pedro, and in the Morro Grande forest reservoir were found to be quite similar (upto 5 microgkg-1dw), this value is considered as the ubiquitous background level. In contrast, the Takimoto 1 sediments showed significantly higher 4-tert-octylphenol concentrations, possibly due to accelerated inputs from adjacent intensively cropped fields. Analysed alkylphenols were not detectable in water samples. 相似文献
48.
PCDD/PCDF,chlorinated pesticides and PAH in Chinese teas 总被引:5,自引:0,他引:5
Four samples of Chinese tea (two green teas, and two brick teas) were analyzed for their concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF), chlorinated pesticides and PAH. The infusions prepared from these teas were also analyzed for PCDD/PCDF. The levels of DDT and its metabolites in tea leaves were within the safety limit of 0.2 mg/kg. Rather high levels of total PAH were obtained in brick tea (1048–1162 mg/kg), when compared with green tea (497–517 mg/kg). In terms of PCDD/PCDF, the concentrations of green tea and brick tea differed by a factor of 16, while the concentrations of all infusions were within a factor of 2. The dioxin concentrations in green tea leaves can be explained through uptake of atmospheric PCDD/PCDF. The higher concentrations in the brick tea leaves are due the longer exposure time, and to certain extent, the use of old leaves, branches and roots when making the tea, and additional components such as soil particulates through contamination. Certain Chinese populations drinking a large amount of brick tea (>3 l per day) indicated that individuals of these populations consume more tea than Europeans or North Americans result in a comparably higher intake of PCDD/PCDF. Tea consumption can attribute to up to 10% of the TDI recommended by WHO (only PCDD/PCDF considered, no PCB analyzed). 相似文献
49.
50.