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Uptake of organic contaminants by plant roots consists of two consecutive steps: sorption to plant roots and entrance into root xylem tissues through epidermal and endodermic membranes. Most research pertaining to phytoremediation assumed that sorption to plant roots is linear and non-competitive. A growing body of evidence, however, is suggesting that sorption to plant roots is nonlinear and competitive. The objective of this study was to examine the concentration effects of chemical constituents on the competitive sorption of trichloroethylene (TCE) and tetrachloroethylene (PCE) to the roots of Typha latifolia. Competitive sorption was clearly demonstrated by the reduced sorption of TCE and PCE in bi-solute systems than in single-solute systems. Concentration is an important factor affecting the extent of competition. In bi-solute systems, the PCE/TCE ratio on root surface approximately reflected the contaminant footprints in solution. The result was attributed to limited high energetically favorable sorption sites on the root surface and similar sorption mechanisms of TCE and PCE. The results hold significant importance for the application of phytomonitoring of organic contaminant mixtures. 相似文献
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Sharma Virender K. Ma Xingmao Lichtfouse Eric Robert Didier 《Environmental Chemistry Letters》2023,21(4):1933-1936
Environmental Chemistry Letters - Nanoplastics are probably much more dangerous for living organisms than microplastics because they are more abundant and reactive. They can potentially... 相似文献
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Sorption to plant roots is the first step for organic contaminants to enter plant tissues. Mounting evidence is showing that sorption to plant roots is nonlinear and competitive. The objective of this study was to investigate the effects of physiochemical properties of homologous chlorinated ethenes and ethanes on the competitive sorption of trichloroethylene (TCE) to the roots of Typha latifolia (cattail). The results showed that chlorinated ethenes exerted significantly stronger competition on the sorption of TCE than chlorinated ethanes. Individual physiochemical properties of organic compounds could be related to the competitive capacity of chlorinated ethenes, but the roles appeared secondary, with molecular structures showing primary effects. Based on these observations, a two-step sorption mechanism was proposed, consisting of the interactions between organic compounds and functional groups on the root surface and subsequent pore filling and absorption to the hydrophobic domains in the composition of roots. 相似文献
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Wen Yinghao Lichtfouse Eric Sharma Virender K. Ma Xingmao 《Environmental Chemistry Letters》2023,21(1):15-20
Environmental Chemistry Letters - The persistence of recalcitrant pollutants in water is a major health issue calling for advanced and green techniques to clean polluted waters. For instance,... 相似文献
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Effects of particle composition and environmental parameters on catalytic hydrodechlorination of trichloroethylene by nanoscale bimetallic Ni-Fe 总被引:1,自引:0,他引:1
Jianjun Wei Yajing Qian Wenjuan Liu Lutao Wang Yijie Ge Jianghao Zhang Jiang Yu Xingmao Ma 《环境科学学报(英文版)》2014,26(5):1162-1170
Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene (TCE), one of the most commonly detected chlorinated organic compounds in groundwater. Ethane was the predominant product. The greatest dechlorination efficiency was achieved at 22 molar percent of nickel. This nanoscale Ni-Fe is poorly ordered and inhomogeneous; iron dissolution occurred whereas nickel was relatively stable during the 24-hr reaction. The morphological characterization provided significant new insights on the mechanism of catalytic hydrodcchlorination by bimetallic nanoparticles. TCE degradation and ethane production rates were greatly affected by environmental parameters such as solution pH, temperature and common groundwater ions. Both rate constants decreased and then increased over the pH range of 6.5 to 8.0, with the minimum value occurring at pH 7.5. TCE degradation rate constant showed an increasing trend over the temperature range of 10 to 25℃. However, ethane production rate constant increased and then decreased over the range, with the maximum value occurring at 20℃, Most salts in the solution appeared to enhance the reaction in the first half hour but overall they displayed an inhibitory effect. Combined ions showed a similar effect as individual salts. 相似文献
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Wen Yinghao Yuan Jieming Ma Xingmao Wang Shiren Liu Yuchen 《Environmental Chemistry Letters》2019,17(4):1539-1551
Environmental Chemistry Letters - Water scarcity is a pressing global challenge. Filtration with actual polymeric membranes shows good capability for pollutant separation, but broad applications of... 相似文献
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一种新型的生物处理技术—膜生物反应器 总被引:13,自引:0,他引:13
膜生物反应器是近年来发展起来的一种新型的处理技术,现就膜生物反应器的应用类型,机理进行阐述,并对膜生物反应器存在问题和应用前景作了说明,指出膜生物反应器将会成为21世纪的一种重要的污水处理技术。 相似文献
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