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481.
Achour Terbouche Chafia Ait Ramdane-Terbouche Didier Hauchar Safia Djebbar 《环境科学学报(英文版)》2011,23(7):1095-1103
The adsorption capacities of new humic acids isolated from Yakouren forest (YHA) and Sahara (Tamenrasset: THA) soils (Algeria)
and commercial humic acid (PFHA) on polyaniline emeraldine base (PEB) were studied at pH 6.6. Also the adsorption of heavy
metals such as Cd2+, Zn2+ and Ni2+ on humic acid-polyaniline systems (HA-PEB) was investigated at the same conditions. HA-PEB
compounds were characterized by scanning electron microscopy (SEM), infrared spectrometry and cavity microelectrode. In addition,
batch adsorption and cavity microelectrode were used in the adsorption study of Cd2+, Zn2+ and Ni2+ on HA-PEB. To develop biocaptors
of polluting metals using a cavity microelectrode modified by HA-PEB systems, the adsorption kinetic and adsorption capacity were
investigated. The SEM analysis showed that the presence of humic acid affected the PEB surface and caused the formation of a
granular morphology. The maximum adsorption capacities (qmax) of PFHA, THA and YHA determined by adsorption isotherms were
91.31, 132.1 and 151.0 mg/g, respectively. Batch adsorption results showed that qmax of Cd2+, Zn2+ and Ni2+ on HA-PEB followed
the order: THA-PEB > YHA-PEB > PFHA-PEB. The voltammograms obtained with HA-PEB modified cavity microelectrode showed
the appearance of new redox couples reflecting the adsorption of HA on PEB. Metal-humic acid-polyaniline voltammograms were
characterized by appearance of oxidation-reduction couples or reduction wave corresponding to metal. Finally, the result may be
exploited to develop a biocaptor based on the cavity microelectrode amended by THA-PEB and YHA-PEB. 相似文献
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文章提取了3期遥感数据的湿地类型,通过对景观格局的动态变化分析,说明了人为干扰和气候因素对岱海湿地的影响,为湿地管理提供了依据。 相似文献
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结合环境监测仪器设备的特点,着重阐述了从设备分类、量值溯源、维修维护等几方面环境监测设备的常规管理方法,并对其现代化的管理进行了探索。 相似文献
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Evaluation of accuracy of linear regression models in predicting urban stormwater discharge characteristics 总被引:1,自引:0,他引:1
Stormwater runoff has been identified as a source of pollution for the environment, especially for receiving waters. In order to quantify and manage the impacts of stormwater runoff on the environment, predictive models and mathematical models have been developed. Predictive tools such as regression models have been widely used to predict stormwater discharge characteristics. Storm event characteristics, such as antecedent dry days (ADD), have been related to response variables, such as pollutant loads and concentrations. However it has been a controversial issue among many studies to consider ADD as an important variable in predicting stormwater discharge characteristics. In this study, we examined the accuracy of general linear regression models in predicting discharge characteristics of roadway runoff. A total of 17 storm events were monitored in two highway segments, located in Gwangju, Korea. Data from the monitoring were used to calibrate United States Environmental Protection Agency's Storm Water Management Model (SWMM). The calibrated SWMM was simulated for 55 storm events, and the results of total suspended solid (TSS) discharge loads and event mean concentrations (EMC) were extracted. From these data, linear regression models were developed. R2 and p-values of the regression of ADD for both TSS loads and EMCs were investigated. Results showed that pollutant loads were better predicted than pollutant EMC in the multiple regression models. Regression may not provide the true effect of site-specific characteristics, due to uncertainty in the data. 相似文献