The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)r...The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)removal from water was evaluated and optimized using the Response Surface Methodology(RSM).Under optimized conditions(adsorbent dose:20 mg;contact time:30 min;initial Pb(II)concentration:120 mg.L^(−1);and pH:8),the removal of Pb(II)was 99.77%.The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm models.The Langmuir isotherm model fits the experimental data.This shows that the surface of the silica gel synthesized from chemical bottles waste was covered by a Pb(II)monolayer.XRF analysis showed that the synthesized silica gel had a SiO_(2) content of 75.63%.Amorphous silica was observed from XRD analysis.SEM-EDX characterization showed that Pb was adsorbed on the silica gel surface.SEM analysis showed that silica gel has irregular particles with a surface area of 297.08 m2.g^(−1) with a pore radius of 15.74 nm calculated from BET analysis.展开更多
Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology w...Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology was used to optimize three environmental factors(temperature, light intensity and total dissolved solids) of allelopathic effects of Potamogeton pectinatus against Microcystis aeruginosa at the same time. By solving the regression equation and analyzing the response surface contour plots, the optimal conditions of the relatively inhibitory rate of Microcystis aeruginosa were that the temperature was 23℃, the light intensity was 2,700,lx and the total dissolved solids were 4,415,mg/L. Under these conditions, the optimal value of relatively inhibitory rate of Microcystis aeruginosa was 81.9%. According to validation experiments, the results of analysis indicated that the experimental values fitted well with the predicted ones.展开更多
Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for t...Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for the separation of interested components. Box-Behnken factorial design was effectively applied for the separation optimization of eight structurally related sulfonamides using capillary zone electrophorosis and reverse high performance liquid chromatography. Optimum values for volume ratio of THF to H2O in eluent, column temperature and flow rate of eluent are found as 12 to 88, 35℃ and 1.0 mL/min, respectively. Box-Behnken modified optimization model is extended to separation by capillary electrophoresis (CE). While using CE, a satisfactory separation is achieved with a minimum resolution larger than 1.0 for a separation time less than 10 min.展开更多
Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clito...Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The criticalfactors selected for the investigation were cultivation temperature, time and volume ofmedium, based on the results of previous Plackett-Burman design. By analyzing theresponse surface plots, the optimum ranges of cultivation temperature, time and mediumvolume for obtaining over 1 253.00gmL-1 of EPC lie in 24.325.8℃, 9.710.2d and 76.090.0mL, respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight (DCW), theabove variables would be in the range of 23.824.8℃, 9.610.3d and 71.098.0mL,respectively. By solving the inverse matrix from the quadratic regression equations, theoptimal conditions to gain 1 265.45gmL-1 of EPC were 25.0℃, 9.9d and 83.4mL, to gain8.50mg mL-1 of DCW were 24.4℃, 9.9d and 87.1mL. In order to obtain the maximum yield ofEPC and DCW at the same time, the above conditions would be 24.5℃, 9.9d and 84.7mL,respectively, in this situation, the maximum predicted EPC and DCW were 1 261.60gmL-1and 8.47mgmL-1, respectively. The experimental data under various conditions have validatedthe theoretical values.展开更多
In this work the effects of the contents of nickel(5,7.5,10 wt%)and copper(0,1,2 wt%)and reaction temperature(650,700,750°C)on the catalytic performance of Ni–Cu/Al_2O_3catalyst in methane dry reforming were eva...In this work the effects of the contents of nickel(5,7.5,10 wt%)and copper(0,1,2 wt%)and reaction temperature(650,700,750°C)on the catalytic performance of Ni–Cu/Al_2O_3catalyst in methane dry reforming were evaluated using Box–Behnken design in order to optimize methane conversion,H_2/CO ratio and the catalyst deactivation.Different catalysts were prepared by co-impregnation method and characterized by XRD,BET,H_2-TPR,FESEM and TG/DTA analyses.The results revealed that copper addition improved the catalyst reducibility.Promoted catalyst with low amounts of Cu gave higher activity and stability with high resistance to coke deposition and agglomeration of active phase especially during the reaction.However catalysts with high amounts of Cu were less active and rather deactivated due to the active sites sintering as well as Ni covering by Cu-enriched phase.The optimal conditions were determined by desirability function approach as 10 wt%of Ni,0.83 wt%of Cu at 750°C.CH_4conversion of95.1%,H_2/CO ratio of 1 and deactivation of 1.4%were obtained experimentally under optimum conditions,which were in close agreement with the values predicted by the developed model.展开更多
Disulfide bond formation protein A (DsbA) is one of the important helper proteins for folding in protein synthesis in vivo. In this study, purification of recombinant DsbA was investigated by examining four important ...Disulfide bond formation protein A (DsbA) is one of the important helper proteins for folding in protein synthesis in vivo. In this study, purification of recombinant DsbA was investigated by examining four important factors with Box-Behnken design method, a statistic-based design of experiments. The optimal operation conditions were obtained by adopting the effectiveness coefficient method on the multi-objective problem, which takes the protein recovery, purification efficiency and throughput of ion-exchange chromatography into account. After the optimization, protein recovery of 96.8% and purity higher than 95% DsbA was achieved, and the productivity was (377.9±1.7)mg soluble DsbA per liter broth. The purified protein was identified by peptide mass fingerprinting matching the record of gi|2624856, a mutant of DsbA. The DsbA was preliminarily applied to the refolding of denatured lysozyme in vitro.展开更多
Electrospun poly(vinyl alcohol)/chitosan nanofibers had their solution and process parameters optimized using a Box-Behnken design and desirability function. Four factors (applied voltage, flow rate, distance tip-to-p...Electrospun poly(vinyl alcohol)/chitosan nanofibers had their solution and process parameters optimized using a Box-Behnken design and desirability function. Four factors (applied voltage, flow rate, distance tip-to-plate and amount of chitosan) were varied to produce electrospun mats with a low fiber diameter. An empirical model was developed for each response using response surface methodology (RSM), which revealed that flow rate had no significant influence on the assessed responses. With desirability function, the optimal conditions to produce the nanofibers were applied voltage of 13.1 kV, 30% chitosan concentration and distance tip-to-plate of 10 cm. The fiber diameter and standard deviation were 196.5 ± 28.3 nm, compared to the predicted values of 185.9 ± 26.8 nm. The desirability function allied with Box-Benhken design proved themselves important tools to predict process parameters for the development of nanofibers. The mats were crosslinked with glutaraldehyde for 24 h and 48 h and presented good water stability and enhanced mechanical properties.展开更多
The present work aims to optimize the foaming conditions for tomato juice using three level Box-Behnken Experimental Design of Response surface Methodology. In the following study three process parameters namely conce...The present work aims to optimize the foaming conditions for tomato juice using three level Box-Behnken Experimental Design of Response surface Methodology. In the following study three process parameters namely concentration of egg albumin (EA) as foaming agent, Carboxy methyl cellulose (CMC) as foam stabilizer and whipping time (WT) was optimized. The levels for various input variables were EA: 5% - 15%, CMC: 0.10% - 0.60% & WT: 3 - 7 min. The responses measured were expansion volume (EV), foam density (FD) and drainage volume (DV) which are an indication of foaming ability and foam stability. The predicted levels of responses as generated by software were EV: 91.49%, FD: 0.558 g/cc & DV: 10 ml, which on validation was found closer to experimental value.展开更多
文摘The adsorption of Pb(II)on silica gel synthesized from chemical glass bottle waste has been studied.The effect of independent variables(adsorbent dose,initial concentration of Pb(II),contact time,and pH)on the Pb(II)removal from water was evaluated and optimized using the Response Surface Methodology(RSM).Under optimized conditions(adsorbent dose:20 mg;contact time:30 min;initial Pb(II)concentration:120 mg.L^(−1);and pH:8),the removal of Pb(II)was 99.77%.The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm models.The Langmuir isotherm model fits the experimental data.This shows that the surface of the silica gel synthesized from chemical bottles waste was covered by a Pb(II)monolayer.XRF analysis showed that the synthesized silica gel had a SiO_(2) content of 75.63%.Amorphous silica was observed from XRD analysis.SEM-EDX characterization showed that Pb was adsorbed on the silica gel surface.SEM analysis showed that silica gel has irregular particles with a surface area of 297.08 m2.g^(−1) with a pore radius of 15.74 nm calculated from BET analysis.
基金Supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2012BAC13B05)Science and Technology Foundation of Beijing Municipal Research Institute of Environmental Protection(No.2013B05)
文摘Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology was used to optimize three environmental factors(temperature, light intensity and total dissolved solids) of allelopathic effects of Potamogeton pectinatus against Microcystis aeruginosa at the same time. By solving the regression equation and analyzing the response surface contour plots, the optimal conditions of the relatively inhibitory rate of Microcystis aeruginosa were that the temperature was 23℃, the light intensity was 2,700,lx and the total dissolved solids were 4,415,mg/L. Under these conditions, the optimal value of relatively inhibitory rate of Microcystis aeruginosa was 81.9%. According to validation experiments, the results of analysis indicated that the experimental values fitted well with the predicted ones.
基金Project(20235010) support by the NSFC-KOSEF Scientific Cooperation ProgramProject supported by the Program for New Century Talents of University in Henan ProvinceProgram for Backbone Teacher in Henan Province, China
文摘Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for the separation of interested components. Box-Behnken factorial design was effectively applied for the separation optimization of eight structurally related sulfonamides using capillary zone electrophorosis and reverse high performance liquid chromatography. Optimum values for volume ratio of THF to H2O in eluent, column temperature and flow rate of eluent are found as 12 to 88, 35℃ and 1.0 mL/min, respectively. Box-Behnken modified optimization model is extended to separation by capillary electrophoresis (CE). While using CE, a satisfactory separation is achieved with a minimum resolution larger than 1.0 for a separation time less than 10 min.
文摘Response surface (RSM) methodology based on a three-level three-factor Box-Behnkendesign of experiment was used to optimize the exopolysaccharide content (EPC) and themycelium biomass in submerged cultivation by Clitocybe sp. AS 5.112. The criticalfactors selected for the investigation were cultivation temperature, time and volume ofmedium, based on the results of previous Plackett-Burman design. By analyzing theresponse surface plots, the optimum ranges of cultivation temperature, time and mediumvolume for obtaining over 1 253.00gmL-1 of EPC lie in 24.325.8℃, 9.710.2d and 76.090.0mL, respectively. While for obtaining over 8.32 mg mL-1 of dry cell weight (DCW), theabove variables would be in the range of 23.824.8℃, 9.610.3d and 71.098.0mL,respectively. By solving the inverse matrix from the quadratic regression equations, theoptimal conditions to gain 1 265.45gmL-1 of EPC were 25.0℃, 9.9d and 83.4mL, to gain8.50mg mL-1 of DCW were 24.4℃, 9.9d and 87.1mL. In order to obtain the maximum yield ofEPC and DCW at the same time, the above conditions would be 24.5℃, 9.9d and 84.7mL,respectively, in this situation, the maximum predicted EPC and DCW were 1 261.60gmL-1and 8.47mgmL-1, respectively. The experimental data under various conditions have validatedthe theoretical values.
文摘In this work the effects of the contents of nickel(5,7.5,10 wt%)and copper(0,1,2 wt%)and reaction temperature(650,700,750°C)on the catalytic performance of Ni–Cu/Al_2O_3catalyst in methane dry reforming were evaluated using Box–Behnken design in order to optimize methane conversion,H_2/CO ratio and the catalyst deactivation.Different catalysts were prepared by co-impregnation method and characterized by XRD,BET,H_2-TPR,FESEM and TG/DTA analyses.The results revealed that copper addition improved the catalyst reducibility.Promoted catalyst with low amounts of Cu gave higher activity and stability with high resistance to coke deposition and agglomeration of active phase especially during the reaction.However catalysts with high amounts of Cu were less active and rather deactivated due to the active sites sintering as well as Ni covering by Cu-enriched phase.The optimal conditions were determined by desirability function approach as 10 wt%of Ni,0.83 wt%of Cu at 750°C.CH_4conversion of95.1%,H_2/CO ratio of 1 and deactivation of 1.4%were obtained experimentally under optimum conditions,which were in close agreement with the values predicted by the developed model.
基金Supported by the National Natural Science Foundation of China （21036005）.
文摘Disulfide bond formation protein A (DsbA) is one of the important helper proteins for folding in protein synthesis in vivo. In this study, purification of recombinant DsbA was investigated by examining four important factors with Box-Behnken design method, a statistic-based design of experiments. The optimal operation conditions were obtained by adopting the effectiveness coefficient method on the multi-objective problem, which takes the protein recovery, purification efficiency and throughput of ion-exchange chromatography into account. After the optimization, protein recovery of 96.8% and purity higher than 95% DsbA was achieved, and the productivity was (377.9±1.7)mg soluble DsbA per liter broth. The purified protein was identified by peptide mass fingerprinting matching the record of gi|2624856, a mutant of DsbA. The DsbA was preliminarily applied to the refolding of denatured lysozyme in vitro.
文摘Electrospun poly(vinyl alcohol)/chitosan nanofibers had their solution and process parameters optimized using a Box-Behnken design and desirability function. Four factors (applied voltage, flow rate, distance tip-to-plate and amount of chitosan) were varied to produce electrospun mats with a low fiber diameter. An empirical model was developed for each response using response surface methodology (RSM), which revealed that flow rate had no significant influence on the assessed responses. With desirability function, the optimal conditions to produce the nanofibers were applied voltage of 13.1 kV, 30% chitosan concentration and distance tip-to-plate of 10 cm. The fiber diameter and standard deviation were 196.5 ± 28.3 nm, compared to the predicted values of 185.9 ± 26.8 nm. The desirability function allied with Box-Benhken design proved themselves important tools to predict process parameters for the development of nanofibers. The mats were crosslinked with glutaraldehyde for 24 h and 48 h and presented good water stability and enhanced mechanical properties.
文摘The present work aims to optimize the foaming conditions for tomato juice using three level Box-Behnken Experimental Design of Response surface Methodology. In the following study three process parameters namely concentration of egg albumin (EA) as foaming agent, Carboxy methyl cellulose (CMC) as foam stabilizer and whipping time (WT) was optimized. The levels for various input variables were EA: 5% - 15%, CMC: 0.10% - 0.60% & WT: 3 - 7 min. The responses measured were expansion volume (EV), foam density (FD) and drainage volume (DV) which are an indication of foaming ability and foam stability. The predicted levels of responses as generated by software were EV: 91.49%, FD: 0.558 g/cc & DV: 10 ml, which on validation was found closer to experimental value.
