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Title: Science in China Series C-Life Sciences
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- Title: Science in China Series D-Earth Sciences
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Title: Science in China Series C-Life SciencesFull Journal Title: Science in China Series C-Life Sciences ISO Abbreviated Title: Sci. China Ser. C-Life Sci. JCR Abbreviated Title: Sci China Ser C ISSN: 1006-9305 Issues/Year: 6 Journal Country Peoples R China Language: English Publisher: Science Press Publisher Address: 16 Donghuangchenggen North St, Beijing 100717, Peoples R China Subject Categories: Biology: Impact Factor
ISO Abbreviated Title: Sci. China Ser. D-Earth Sci. JCR Abbreviated Title: Sci China Ser D ISSN: 1006-9313 Issues/Year: 6 Journal Country Peoples R China Language: English Publisher: Science Press Publisher Address: 16 Donghuangchenggen North St, Beijing 100717, Peoples R China Subject Categories: Geosciences, Interdisciplinary: Impact Factor ? Liao, L.B. and Fraser, D.G. (2005), Adsorption of As on hydroxy-Fe-montmorillonite complexes. Science in China Series D-Earth Sciences, 48 (12), 2155-2165. Abstract: Arsenate has high affinity for soluble hydroxy-Fe species and Fe-oxyhydroxide precipitates. In addition, the hydrolysis of Fe(III) and the growth of the initially precipitated Fe(III) phases are strongly influenced by the presence of montmorillonite. In this paper, the adsorption of As onto various hydroxy-Fe-montmorillonite (H-F-M) complexes was studied. Three systems of samples were prepared by mixing montmorillonite, hydroxy-Fe and arsenate in different sequences: (1) Prior mixing of montmorillonite and hydroxy-Fe before the addition of arsenate, (2) prior mixing of hydroxy-Fe and arsenate before the addition of montmorilionite, and (3) prior mixing of montmorillonite and arsenate before the addition of hydroxy-Fe. For each system, the effects of pH, ionic strength, temperature, initial Fe and As concentrations and adsorption duration on the overall uptake of As by H-F-M complexes were studied. Results showed that the uptake of As increased with increasing pH, temperature, initial Fe concentration and adsorption duration, and decreased with increasing ionic strength and initial As concentration to different extents for the three systems. The variation of the As uptake of H-F-M complexes with pH in the range of study is opposite to that reported previously for Fe-O-H systems in the absence of montmorillonite and similar to that reported for montmorillonite in the absence of hydroxy-Fe. The marked influence of ionic strength on the As uptake of H-F-M complexes indicates that outer-sphere complexation plays an important role. This is quite different from the adsorption of As on the surface of either Fe-oxyhydroxides or montmorillonite alone in which inner-sphere complexation dominates. Under all experimental conditions, the H-F-M complexes studied displayed a very strong affinity for As, among which system 2 had the highest As adsorption capacity and system 1 the lowest. The authors attribute this to the differences in mixing sequence which resulted in more hydroxy-Fe (the main adsorbent for As) in system 1 adsorbing onto montmorillonite before adsorbing As than in systems 2 or 3. Keywords: Adsorption, Adsorption Capacity, Arsenate, Arsenate Adsorption, Clay, Colloidal Particles, Complex, Exafs, Hydrolysis, Hydroxy-Fe, Iron(III), Mechanism, Montmorillonite, Oxyhydroxide, Phosphate Title: Science in China Series E-Technological SciencesFull Journal Title: Science in China Series E-Technological Sciences ISO Abbreviated Title: Sci. China Ser. E-Technol. Sci. JCR Abbreviated Title: Sci China Ser E ISSN: 1006-9321 Issues/Year: 6 Journal Country Peoples R China Language: English Publisher: Science Press Publisher Address: 16 Donghuangchenggen North St, Beijing 100717, Peoples R China Subject Categories: Engineering Materials Science: Impact Factor ? Shen, Y.M., Li, Y.C. and Chwang, A.T. (1996), Quasi 3 dimensional refined modeling of turbulent flow and water quality in coastal waters. Science in China Series E-Technological Sciences, 39, 342-353. Full Text: Sci Chi Ser E-Tec Sci39, 342.pdf Abstract: The water quality in Victoria Harbour, Hong Kong is dominated by strong seasonal effects resulting from the variation in freshwater discharge into the Pearl Estuary. the quasi-three-dimensional water quality model has been developed to simulate the variations in water quality and the ecosystem in the harbour. The model is unique in that it completely integrates the refined modelling of the hydrodynamics, biochemical reactions and the ecosystem in the harbour. It is a quasi-three-dimensional segmented model which is capable of resolving mean daily variations in all the parameters relevant to pollution control. It predicts daily fluctuations in the oxygen content of different depths in water throughout the year. It takes into account transport and settling of pollutant particles. It predicts light penetration from computed turbidity variations. It includes interactions between the ecosystem and water quality, through nutrient cycling and photosynthesis. The model has been calibrated well against the data set of historical water quality observations. ? Long, X.Y., Luo, X.G., Wang, Y. and Li, Z. (2009), Sorption of Pb(II) from aqueous solution by konjac glucomannan beads. Science in China Series E-Technological Sciences, 52 (1), 223-226. Full Text: 2009\Sci Chi Ser E-Tec Sci52, 223.pdf Abstract: Konjac glucomannan beads have been investigated as metal biosorbent for Pb(II) from aqueous solutions. The effect of contact time, solution pH, initial metal concentration, and desorption were studied in batch experiments at 20C±2C. Maximum mental sorption was found to occur at initial pH 4.0-5.5. Kinetic studies revealed that the initial uptake was rapid and equilibrium was established in 3 h and that the data followed the prseudo-second order reaction. The equilibrium sorption data at initial pH 4.0 were described by the Langmuir and Freundlich isotherm models, however, Langmuir isotherm model has been found to provide the best correlation. The highest value of Langmuir maximum uptake (q(max)) was found to be 105.71 mg . g-1. Similar Freundlich empirical constant (KF) was obtained to be 1.98 for lead. Adsorption-complexation may be involved in the sorption process of lead. Desorption experiments showed evidence that after two contacts neither HCl nor EDTA solutions were able to desorb lead from the konjac glucomannan beads, but the desorbtion efficacy of HCl solution was higher than EDTA solution. The results obtained show that konjac glucomannan beads may be used for the treatment of wastewater contaminated with lead. Keywords: Adsorption, Aqueous Solution, Aqueous Solutions, Batch, Batch Experiments, Beads, Biosorbent, Biosorption, Concentration, Contact, Correlation, Data, Desorption, EDTA, Efficacy, Equilibrium, Evidence, Experiments, Freundlich, Freundlich Isotherm, Heavy-Metal Ions, Isotherm, Isotherm Model, Isotherm Models, Kinetic, Kinetic Studies, Konjac Glucomannan, Langmuir, Langmuir Isotherm, Langmuir Isotherm Model, Lead, Metal, Model, Models, Pb(II), pH, Phenol, Process, Solution, Solutions, Sorption, Sorption Process, Treatment, Uptake, Value, Wastewater Directory: ~ysho -> YSHO-English -> Database Database -> Personal Research Database Database -> Personal Research Database Download 6.47 Mb. Share with your friends:
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