排序方式: 共有13条查询结果,搜索用时 218 毫秒
1.
Size measurements of atmospheric aerosol, using impactors and Nuclepore filters have been carried out. Analysis were made by electron and optic microscopy. Thus we obtain a size distribution from Dp = 10?2μm to Dp = 70 μm over the Atlantic Ocean and at urban location. The statistical analysis of the curves allows to compare the results and to point out the effect of an urban pollution on a marine aerosol. 相似文献
2.
3.
4.
5.
6.
7.
8.
9.
10.
Ecotoxicity characterization of dinitrotoluenes and some of their reduced metabolites 总被引:3,自引:0,他引:3
In the present study, the toxic effects of 2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT) and a selection of their respective metabolites were examined and compared to 2,4,6-trinitrotoluene (TNT) using the 15-min Microtox (Vibrio fischen) and 96-h freshwater green alga (Selenastrum capricomutum) growth inhibition tests. All of the compounds tested were less toxic than TNT. Using the Microtox assay, 2,6-DNT was more toxic than 2,4-DNT and the order of toxicity for 2,6-DNT and its metabolites was: 2,6-DNT > or = 2A-6NT > 2,6-DAT; whereas that for 2,4-DNT was: 4A-2NT > 2A-4NT > 2,4-DNT > 2,4-DAT. For the algal test, 2,4-DNT was more toxic than 2,6-DNT and the order of toxicity for 2,4-DNT and its metabolites was: 2,4-DNT > 2,4-DAT approximately equal to 4A-2NT = 2A-4NT. The order of toxicity for 2,6-DNT and its reduced metabolites using the algal test was very similar to the Microtox bioassay. These results demonstrate that the reduced metabolites of 2,6-DNT tested in this study were less toxic than that of the parent compound, but certain partially reduced metabolites of 2,4-DNT can be more toxic than the parent molecule. These data put into question the general hypothesis that reductive metabolism of nitro-aromatics is associated with a sequential detoxification process. 相似文献