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201.
金沙江流域水土流失现状与河道泥沙分析 总被引:14,自引:1,他引:13
对金沙江流域水土流失、河道泥沙及主要影响因素系统作了分析,认为地质、地貌及气候因子是影响水土流失的主要因素,人为活动加剧水土流失的发生发展。河道泥沙主要来自金沙江下游,特别是下游干流河谷区间,流域的地面侵蚀与河道泥沙的空间关系不密切,影响输沙量的主要因素为年径流量和清水区年径流量,以及滑坡、泥石流等重力侵蚀,尽管水土流失治理对于流域的河道泥沙减沙效应显著,但短期内对流域干支流输沙量影响甚微。今后一段时间内金沙江流域河道泥沙不会有显著的变化 相似文献
202.
A 6-month greenhouse pot trial was performed, aimed at screening appropriate Sesbania species for remediation of Pb/Zn and Cu mine tailings. Performances of young seedlings of four Sesbania species (S. cannabina, S. grandiflora, S. rostrata, and S. sesban) were compared with and without inoculation of rhizobia. Seedlings were planted in two types of tailings amended with garden soil or garden soil mixed with river sediment. The results indicated that inoculated plants generally produced a higher biomass than samples without inoculation. Pb/Zn mine tailings containing rather high concentrations of total and water-soluble Cu, Pb, and Zn were toxic to plant growth compared with Cu mine tailings, according to the growth performance of the four species. Sesbania sesban and S. rostrata showed superior growth performance, compared to the other two species. Thus, they can serve as pioneer species to modify the barren environment, by providing organic matter and essential nutrients such as nitrogen, upon decomposition, in a relatively short period of time. This is especially true for S. rostrata, which is an annual plant that forms both stem and root nodules. However, a longer-term field trial should be conducted to investigate if superior species can beneficially modify the habitat for the growth of subsequent plant communities. 相似文献
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用研制的SC菌剂作生物吸附剂 ,研究了其在不同菌铜比 ,pH、温度及作用时间条件下对Cu2 的去除效果。结果表明 ,在获得的最佳条件下 ,对不同Cu2 浓度的印刷电路板废水中Cu2 的去除效果明显 ,达 95 48%和 86 74%。 相似文献
207.
LFB是Basofil纤维与Metmax纤维混合制成的针刺毡,本文主要介绍Basofil纤维和LFB的物理和化学特性。 相似文献
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Uniparental disomy (UPD) is an uncommon chromosome condition, but UPD involving chromosome 21 is rarely reported. We reported here a case who had first trimester screening test for Down syndrome, chorionic villus sampling for fetal karyotyping, quantitative fluorescence polymerase chain reaction (QF-PCR), as well as non-invasive prenatal testing (NIPT) by maternal plasma sequencing. There were discordant results between fetal karyotyping and NIPT due to UPD 21combined with confined placental mosaicism of trisomy 21. This demonstrated that it is possible to detect placental mosaicism by NIPT, but further studies are required to confirm its sensitivity. Therefore, all positive NIPT results must be confirmed by conventional invasive test and karyotyping. QF-PCR has the additional benefit in diagnosing UPD. © 2013 John Wiley & Sons, Ltd. 相似文献
209.
Effect of methylmercury on LPO levels, SH groups and activities of GSH-Px, SOD, XOD in liver of rats 总被引:1,自引:0,他引:1
LIU Jin |yu GUAN Ming SUN Zhi |wei LIN Xiu |wu CAO Peng |yuan MENG Xiang |dong 《环境科学学报(英文版)》2000,(Z1)
iththeintroductionofagriculturalandindustrialdevelopmentandimprovementofhumanlife ,environmentalpollutionbecomesmoreandmoreofconcernforpeople.MeHgisoneoforganiclipidsoluble ,heavymetallicpollutants.Althoughitsbiologicaleffectswerestudiedinmanyfieldsbyre… 相似文献
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