An experiment was conducted to examine the role of Mn in P fixation through comparing with Al and Fe. Hydroxides and oxides of Al, Fe and Mn were prepared in lab under opened and closed conditions to react with phosph...An experiment was conducted to examine the role of Mn in P fixation through comparing with Al and Fe. Hydroxides and oxides of Al, Fe and Mn were prepared in lab under opened and closed conditions to react with phosphate. The newly formed Mn hydroxide showed the strongest P-fixing abilityl even several times higher than Fe hydroxide, but became the lowest rapidly due to ageing when exposed to air. Mn oxide showed the lowest p-fixing ability. Therefore, a sound consideration on P fixation should be based on both quantities and p-fixing abilities of the compounds of Fe, Al and Mn. The importance of Mn on P availability should receive more attention especially under oxidation-reduction dynamic conditions.展开更多
The advantage of using an available and abundant residual biomass, such as lignin, as a raw material for activated carbons is that it provides additional economical interest to the technical studies. In the current in...The advantage of using an available and abundant residual biomass, such as lignin, as a raw material for activated carbons is that it provides additional economical interest to the technical studies. In the current investigation, a more complete understanding of adsorption of Cr（VI） from aqueous systems onto HaPO4-acid activated lignin has been achieved via microcolumns, which were operated under various process conditions. The practice of using microcolumn is appropriate for defining the adsorption parameters and for screening a large number of poten- tial adsorbents. The effects of solution pH （2-8）, initial metal ion concentration （0.483-1.981 mmol.L-1）, flow rate （1.0-3.1 cm3-min-1）, ionic strength （0.01-0.30 mmol-L-1） and adsorbent mass （0.11 0.465 g） on Cr（VI） adsorption were studied by assessing the microcolmnn breakthrough curve. The microcolumn data were fitted by the Thomas model, the modified Dose model and the BDST model. As expected, the adsorption capacity increased with initial Cr（VI） concentration. High linear flow rates, pH values and ionic strength led to early breakthrough of Cr（VI）. The model constants obtained in this study can be used for the design of pilot scale adsorption process.展开更多
The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, tempe...The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, temperature, enzyme amount, solvent,number of methanol added times and two-step methanolysis by using Candida sp. 99-125 as catalyst were investigated. The optimal conditions for processing 1 g rice bran oil were: 0.2 g immobilized lipase, 2 ml n-hexane as solvent, 20% water based on the rice bran oil mass, temperature of 40 °C and two-step addition of methanol. As a result, the fatty acid methyl esters yield was 87.4%. The immobilized lipase was proved to be stable when it was used repeatedly for 7 cycles.展开更多
To establish a theoretical foundation for simultaneous removal of multi-heavy metals,the adsorption of Cu（Ⅱ） and Pb（Ⅱ） ions from their single and binary systems by Ca-alginate immobilized activated carbon and Sa...To establish a theoretical foundation for simultaneous removal of multi-heavy metals,the adsorption of Cu（Ⅱ） and Pb（Ⅱ） ions from their single and binary systems by Ca-alginate immobilized activated carbon and Saccharomyces cerevisiae （CAS） was investigated.The CAS beads were characterized by Scanning electron microscope （SEM） and Fourier transformed infrared spectroscopy （FTTR）.The effect of initial pH,adsorbent dosage,contact time and initial metal ions concentration on the adsorption process was systematically investigated.The experimental maximum contents of Cu（Ⅱ） and Pb（Ⅱ） uptake capacity were determined as 64.90 and 166.31 mg/g,respectively.The pseudo-second-order rate equation and Langmuir isotherm model could explain respectively the kinetic and isotherm experimental data of Cu（Ⅱ） and Pb（Ⅱ） ions in single-component systems with much satisfaction.The experimental adsorption data of Cu（Ⅱ） and Pb（Ⅱ） ions in binary system were best described by the extended Freundlich isotherm and the extended Langmuir isotherm,respectively.The removal of Cu（lⅡ） ions was more significantly influenced by the presence of the coexistent Pb（Ⅱ） species,while the Pb（Ⅱ） removal was affected slightly by varying the initial concentration of Cu（Ⅱ）.The CAS was successfully regenerated using 1 mol/L HNO3 solution.展开更多
Acidic black 10B dye wastewater was treated by chemical oxidation and adsorption of activated carbon fixed bed and all kinds of influential factors of removal CODcr were discussed. When the initial concentration of th...Acidic black 10B dye wastewater was treated by chemical oxidation and adsorption of activated carbon fixed bed and all kinds of influential factors of removal CODcr were discussed. When the initial concentration of the dye was 150 mg/L, CODer was 432 mg/L and chrome was 2800 times, the appropriate conditions determined by the experiment were as follows： r（NaC10）--4.84 g/L, 25 min, pH=6, height of activated carbon fixed bed was 10 cm. Under these conditions, the decolorizing rate can come up to about 100% and total removed rate of CODer reached at 89.6%. Comparison of UV-Vis adsorption spectrums before and after treatment showed that decomposition effects of chemical oxidation and adsorption of activated carbon fixed bed on acidic black 10B dye wastewater were satisfactory.展开更多
L-（＋）-lactic acid production was studied by immobilized Lactobacillus rhamnosus TISTR108 on crude pectin from Krung Kha Mao （Cissampelospareira L.） leaves. Central composite design was employed to determine the m...L-（＋）-lactic acid production was studied by immobilized Lactobacillus rhamnosus TISTR108 on crude pectin from Krung Kha Mao （Cissampelospareira L.） leaves. Central composite design was employed to determine the maximum lactic acid production of 45.40 g/L in predicted model （Y = 43.98 - 2.43X1 ＋ 1.02X2 ＋ 2.96X3 - 8.72X1^2 - 3.99X2^2 - 1.74X3^2） with the factors at 5.9 of cultural medium pH, 37.6 ℃ of process temperature and 202 rpm of liquid agitation. Statistical analyses demonstrated very high significance for the regression model fitted the data adequately and explained the lactic acid production, since the F-value computed 54.89 was much higher than the tabulated F-value 2.08 for the lactic acid production at 5% level for linear and quadratic polynomial regression models. The highest experimental lactic acid production was 46.91 g/L at 72 h of fermentation.展开更多
A novel strategy for efficient immobilization of electroactive Thionine(Th)on the gold(Au)electrode surface based on calcium carbonate-gold nanoparticles(CaCO3-AuNPs)inorganic hybrid composite was proposed and conduct...A novel strategy for efficient immobilization of electroactive Thionine(Th)on the gold(Au)electrode surface based on calcium carbonate-gold nanoparticles(CaCO3-AuNPs)inorganic hybrid composite was proposed and conducted by the strong electrostatic interaction between positively charged Th and negatively charged CaCO3-AuNPs composite.The hybrid composite was obtained by the adsorption of AuNPs onto the surface of CaCO3 microspheres through electrostatic interaction.Due to the microporous architecture,large surface area,and good biocompatibility of CaCO3-AuNPs composite,the amount and stability of the immobilized Th were highly strengthened.The application of the resulting Th modified electrode in the hydrogen peroxide(H2O2)sensor was also investigated.It exhibited rapid response to H2O2 within 3 s.The linear calibration ranged from 8.00×107to 1.06×10 -3mol/L with a detection limit of 2.00×10 -7mol/L.展开更多
In this work, we demonstrate for the first time, a method to synthesize phenylboronic acid-Fe304@polydopamine （Fe3O4@ PDA-PBA） magnetic microspheres via the combination of mussel-inspired polydopamine coating and cl...In this work, we demonstrate for the first time, a method to synthesize phenylboronic acid-Fe304@polydopamine （Fe3O4@ PDA-PBA） magnetic microspheres via the combination of mussel-inspired polydopamine coating and click chemistry. Uniform-size and core-shell structured Fe3O4@PDA-PBA magnetic microspheres with a core diameter of -240 nm and a shell thickness of -13 nm were obtained as identified by the characterization of the morphology, structure and composition of the synthesized microspheres. We evaluated the selectivity and binding capacity of the Fe3O4@PDA-PBA magnetic microsphcres by using standard glycoproteins （ovalbumin, immunoglobulin G and catalase） and nonglycoproteins （human serum albumin, bovine hemoglobin, myoglobin, lysozyme, and ribonuclease A） as model proteins. Adsorption experiments, SDS-PAGE and mass spectrometry analysis demonstrated that the Fe3O4@PDA-PBA magnetic microspheres had much high binding capacity and selectivity for glycoproteins/glycopeptides compared to nonglycoproteins/nonglycopeptides. In addition, the practicability of the Fe3O4@PDA-PBA magnetic microspheres was further assessed by selective capture of glycoproteins from healthy hu- man serum. The good results demonstrated its potential in glycoproteome analysis.展开更多
文摘An experiment was conducted to examine the role of Mn in P fixation through comparing with Al and Fe. Hydroxides and oxides of Al, Fe and Mn were prepared in lab under opened and closed conditions to react with phosphate. The newly formed Mn hydroxide showed the strongest P-fixing abilityl even several times higher than Fe hydroxide, but became the lowest rapidly due to ageing when exposed to air. Mn oxide showed the lowest p-fixing ability. Therefore, a sound consideration on P fixation should be based on both quantities and p-fixing abilities of the compounds of Fe, Al and Mn. The importance of Mn on P availability should receive more attention especially under oxidation-reduction dynamic conditions.
文摘The advantage of using an available and abundant residual biomass, such as lignin, as a raw material for activated carbons is that it provides additional economical interest to the technical studies. In the current investigation, a more complete understanding of adsorption of Cr（VI） from aqueous systems onto HaPO4-acid activated lignin has been achieved via microcolumns, which were operated under various process conditions. The practice of using microcolumn is appropriate for defining the adsorption parameters and for screening a large number of poten- tial adsorbents. The effects of solution pH （2-8）, initial metal ion concentration （0.483-1.981 mmol.L-1）, flow rate （1.0-3.1 cm3-min-1）, ionic strength （0.01-0.30 mmol-L-1） and adsorbent mass （0.11 0.465 g） on Cr（VI） adsorption were studied by assessing the microcolmnn breakthrough curve. The microcolumn data were fitted by the Thomas model, the modified Dose model and the BDST model. As expected, the adsorption capacity increased with initial Cr（VI） concentration. High linear flow rates, pH values and ionic strength led to early breakthrough of Cr（VI）. The model constants obtained in this study can be used for the design of pilot scale adsorption process.
基金Supported by the National High Technology Research and Development Program of China (2006AA020101, 2007AA10Z360,2009AA03Z232)Key Projects in the National Science & Technology Pillar Program during the Eleventh Five-Year Plan Period (2008BA163B07)
文摘The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, temperature, enzyme amount, solvent,number of methanol added times and two-step methanolysis by using Candida sp. 99-125 as catalyst were investigated. The optimal conditions for processing 1 g rice bran oil were: 0.2 g immobilized lipase, 2 ml n-hexane as solvent, 20% water based on the rice bran oil mass, temperature of 40 °C and two-step addition of methanol. As a result, the fatty acid methyl esters yield was 87.4%. The immobilized lipase was proved to be stable when it was used repeatedly for 7 cycles.
基金Project(11JJ2031)supported by the Key Project of Natural Science Foundation of Hunan Province,China
文摘To establish a theoretical foundation for simultaneous removal of multi-heavy metals,the adsorption of Cu（Ⅱ） and Pb（Ⅱ） ions from their single and binary systems by Ca-alginate immobilized activated carbon and Saccharomyces cerevisiae （CAS） was investigated.The CAS beads were characterized by Scanning electron microscope （SEM） and Fourier transformed infrared spectroscopy （FTTR）.The effect of initial pH,adsorbent dosage,contact time and initial metal ions concentration on the adsorption process was systematically investigated.The experimental maximum contents of Cu（Ⅱ） and Pb（Ⅱ） uptake capacity were determined as 64.90 and 166.31 mg/g,respectively.The pseudo-second-order rate equation and Langmuir isotherm model could explain respectively the kinetic and isotherm experimental data of Cu（Ⅱ） and Pb（Ⅱ） ions in single-component systems with much satisfaction.The experimental adsorption data of Cu（Ⅱ） and Pb（Ⅱ） ions in binary system were best described by the extended Freundlich isotherm and the extended Langmuir isotherm,respectively.The removal of Cu（lⅡ） ions was more significantly influenced by the presence of the coexistent Pb（Ⅱ） species,while the Pb（Ⅱ） removal was affected slightly by varying the initial concentration of Cu（Ⅱ）.The CAS was successfully regenerated using 1 mol/L HNO3 solution.
文摘Acidic black 10B dye wastewater was treated by chemical oxidation and adsorption of activated carbon fixed bed and all kinds of influential factors of removal CODcr were discussed. When the initial concentration of the dye was 150 mg/L, CODer was 432 mg/L and chrome was 2800 times, the appropriate conditions determined by the experiment were as follows： r（NaC10）--4.84 g/L, 25 min, pH=6, height of activated carbon fixed bed was 10 cm. Under these conditions, the decolorizing rate can come up to about 100% and total removed rate of CODer reached at 89.6%. Comparison of UV-Vis adsorption spectrums before and after treatment showed that decomposition effects of chemical oxidation and adsorption of activated carbon fixed bed on acidic black 10B dye wastewater were satisfactory.
文摘L-（＋）-lactic acid production was studied by immobilized Lactobacillus rhamnosus TISTR108 on crude pectin from Krung Kha Mao （Cissampelospareira L.） leaves. Central composite design was employed to determine the maximum lactic acid production of 45.40 g/L in predicted model （Y = 43.98 - 2.43X1 ＋ 1.02X2 ＋ 2.96X3 - 8.72X1^2 - 3.99X2^2 - 1.74X3^2） with the factors at 5.9 of cultural medium pH, 37.6 ℃ of process temperature and 202 rpm of liquid agitation. Statistical analyses demonstrated very high significance for the regression model fitted the data adequately and explained the lactic acid production, since the F-value computed 54.89 was much higher than the tabulated F-value 2.08 for the lactic acid production at 5% level for linear and quadratic polynomial regression models. The highest experimental lactic acid production was 46.91 g/L at 72 h of fermentation.
基金supported by the National Natural Science Foundation of China(20775039)
文摘A novel strategy for efficient immobilization of electroactive Thionine(Th)on the gold(Au)electrode surface based on calcium carbonate-gold nanoparticles(CaCO3-AuNPs)inorganic hybrid composite was proposed and conducted by the strong electrostatic interaction between positively charged Th and negatively charged CaCO3-AuNPs composite.The hybrid composite was obtained by the adsorption of AuNPs onto the surface of CaCO3 microspheres through electrostatic interaction.Due to the microporous architecture,large surface area,and good biocompatibility of CaCO3-AuNPs composite,the amount and stability of the immobilized Th were highly strengthened.The application of the resulting Th modified electrode in the hydrogen peroxide(H2O2)sensor was also investigated.It exhibited rapid response to H2O2 within 3 s.The linear calibration ranged from 8.00×107to 1.06×10 -3mol/L with a detection limit of 2.00×10 -7mol/L.
基金financial support from the National Natural Science Foundation of China(21005018,21375018 and 21075016)the National Basic Research Program of China(2010CB732403)+2 种基金the National Science Foundation for Fostering Talents in Basic Research of China(No.J1103303)the Doctoral Fund of Ministry of Education(20103514120002)the Program for Changjiang Scholars and Innovative Research Team in University(IRT1116)
文摘In this work, we demonstrate for the first time, a method to synthesize phenylboronic acid-Fe304@polydopamine （Fe3O4@ PDA-PBA） magnetic microspheres via the combination of mussel-inspired polydopamine coating and click chemistry. Uniform-size and core-shell structured Fe3O4@PDA-PBA magnetic microspheres with a core diameter of -240 nm and a shell thickness of -13 nm were obtained as identified by the characterization of the morphology, structure and composition of the synthesized microspheres. We evaluated the selectivity and binding capacity of the Fe3O4@PDA-PBA magnetic microsphcres by using standard glycoproteins （ovalbumin, immunoglobulin G and catalase） and nonglycoproteins （human serum albumin, bovine hemoglobin, myoglobin, lysozyme, and ribonuclease A） as model proteins. Adsorption experiments, SDS-PAGE and mass spectrometry analysis demonstrated that the Fe3O4@PDA-PBA magnetic microspheres had much high binding capacity and selectivity for glycoproteins/glycopeptides compared to nonglycoproteins/nonglycopeptides. In addition, the practicability of the Fe3O4@PDA-PBA magnetic microspheres was further assessed by selective capture of glycoproteins from healthy hu- man serum. The good results demonstrated its potential in glycoproteome analysis.
