Jatropha curcas L. (JCL) seeds were extracted and transesterified in-situ using supercritical methanol extraction in the absence of catalyst at different temperatures (200-280℃) and pressures (8-12 MPa), and at...Jatropha curcas L. (JCL) seeds were extracted and transesterified in-situ using supercritical methanol extraction in the absence of catalyst at different temperatures (200-280℃) and pressures (8-12 MPa), and at a fixed reaction time of 30 min with seeds-to-methanol ratio of 1:40 w/v. Design of experiment approach using five-level-two-factors design of Response Surface Methodology (RSM) was used to observe the effect of two independent variables i.e. temperature and pressure and the percent of biodiesel yield which required 13 runs. For optimization of the variables, Central Composite Rotatable Design (CCRD) was used for regression analysis and analysis of variance (ANOVA). The optimize conditions suggested by RSM were at T = 280℃ and P = 12.04 MPa. The predicted and experimental biodicsel yields were found to be 56.8% and 59.9%, respectively, with relatively small deviation errors of 1.59%.展开更多
The epoxidation of methyl oleate(MO)was conducted in the presence of aqueous H2O2 as the oxidant and hierarchical TS-1(HTS-1)as the catalyst;the catalyst was synthesized using polyquaternium-6 as the mesopore template...The epoxidation of methyl oleate(MO)was conducted in the presence of aqueous H2O2 as the oxidant and hierarchical TS-1(HTS-1)as the catalyst;the catalyst was synthesized using polyquaternium-6 as the mesopore template.The effects of various parameters,i.e.,H2O2/C=C molar ratio,oxidant concentration,amount of the catalyst,reaction temperature,and time,were systematically studied.Furthermore,response surface methodology(RSM)was used to optimize the conditions to maximize the yield of epoxy MO and to evaluate the significance and interplay of the factors affecting the epoxy MO production.The H2O2/C=C molar ratio and catalyst amount were the determining factors for MO epoxidation,wherein the maximum yield of epoxy MO reached 94.9%over HTS-1 under the optimal conditions.展开更多
Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodo...Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodology (RSM). The optimized production of succinic acid was predicted and the interactive effects between glucose, yeast extract, and magnesium carbonate were investigated. As a result, a model for predicting the concentration of succinic acid production was developed. The accuracy of the model was confirmed by the analysis of variance (ANOVA), and the validity was further proved by verification experiments showing that percentage errors between actual and predicted values varied from 3.02% to 6.38%. In addition, it was observed that the interactive effect between yeast extract and magnesium carbonate was statistically significant. In conclusion, RSM is an effective and useful method for optimizing the medium components and investigating the interactive effects, and can provide valuable information for succinic acid scale-up fermentation using A. succinogenes strain BE-I.展开更多
This paper describes the optimization of the impeller having splitters for a turbo blower.Two design variables,chord of splitter and pitch of splitter,are introduced to enhance the blower performance.Blower pressure a...This paper describes the optimization of the impeller having splitters for a turbo blower.Two design variables,chord of splitter and pitch of splitter,are introduced to enhance the blower performance.Blower pressure and ef-ficiency are selected as an object function,and the optimization of the blower impeller is performed by a response surface method (RSM).Three-dimensional Navier-Stokes equations are introduced to analyze the internal flow of the blower and to find the value of the object function for each case.Throughout the shape optimization of the splitters attached to the impeller in the turbo blower,pressure and efficiency at the design flow condition are suc-cessively increased by 5.9 percent and 17.9 percent respectively based on the reference blower.The higher blower efficiency obtained by optimization of impeller having splitters is mainly caused by reducing the number of im-peller blades and optimal design of splitters in the blade passage while pressure increase keeps almost the same with the reference blower.For the object function of pressure,pressure increase is obtained at the design and off-design conditions while efficiency keeps higher compared to the reference blower.The enhancement of blow-er performance is due to the reduction of reverse and circulation flows in the blade passage.展开更多
The propulsive efficiency of a plunging NACA0012 airfoil is maximized by means of a simple numerical optimization method based on the response surface methodology (RSM). The control parameters are the amplitude and ...The propulsive efficiency of a plunging NACA0012 airfoil is maximized by means of a simple numerical optimization method based on the response surface methodology (RSM). The control parameters are the amplitude and the reduced frequency of the harmonic sinusoidal motion. The 2D unsteady laminar flow around the plunging airfoil is computed by solving the Navier-Stokes equations for three Reynolds number values (Re = 3.3× 10^3, 1.1×10^4, and 2.2 × 10^4). The Nelder-Mead algorithm is used to find the best control parameters leading to the optimal propulsive efficiency over the constructed response surfaces. It is found that, for a given efficiency level and regardless of the considered Re value, it is possible either to obtain high thrust by selecting a high oscillation frequency or to reduce the input power by adopting a low plunging amplitude. Key words: Plunging airfoil, Propulsive efficiency, Optimization, Response surface methodology (RSM)展开更多
文摘Jatropha curcas L. (JCL) seeds were extracted and transesterified in-situ using supercritical methanol extraction in the absence of catalyst at different temperatures (200-280℃) and pressures (8-12 MPa), and at a fixed reaction time of 30 min with seeds-to-methanol ratio of 1:40 w/v. Design of experiment approach using five-level-two-factors design of Response Surface Methodology (RSM) was used to observe the effect of two independent variables i.e. temperature and pressure and the percent of biodiesel yield which required 13 runs. For optimization of the variables, Central Composite Rotatable Design (CCRD) was used for regression analysis and analysis of variance (ANOVA). The optimize conditions suggested by RSM were at T = 280℃ and P = 12.04 MPa. The predicted and experimental biodicsel yields were found to be 56.8% and 59.9%, respectively, with relatively small deviation errors of 1.59%.
基金supported by the Evonik Industries AGthe Program for New Century Excellent Talents in University(NCET-04-0270)~~
文摘The epoxidation of methyl oleate(MO)was conducted in the presence of aqueous H2O2 as the oxidant and hierarchical TS-1(HTS-1)as the catalyst;the catalyst was synthesized using polyquaternium-6 as the mesopore template.The effects of various parameters,i.e.,H2O2/C=C molar ratio,oxidant concentration,amount of the catalyst,reaction temperature,and time,were systematically studied.Furthermore,response surface methodology(RSM)was used to optimize the conditions to maximize the yield of epoxy MO and to evaluate the significance and interplay of the factors affecting the epoxy MO production.The H2O2/C=C molar ratio and catalyst amount were the determining factors for MO epoxidation,wherein the maximum yield of epoxy MO reached 94.9%over HTS-1 under the optimal conditions.
基金supported by the National Major Special Project on New Varieties Cultivation for Transgenic Organisms(No.2009ZX08009-130B)the National Natural Science Foundation of China(No.50874112)the National High-Tech R&D Program(863)of China(No.2009AA06Z320)
文摘Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodology (RSM). The optimized production of succinic acid was predicted and the interactive effects between glucose, yeast extract, and magnesium carbonate were investigated. As a result, a model for predicting the concentration of succinic acid production was developed. The accuracy of the model was confirmed by the analysis of variance (ANOVA), and the validity was further proved by verification experiments showing that percentage errors between actual and predicted values varied from 3.02% to 6.38%. In addition, it was observed that the interactive effect between yeast extract and magnesium carbonate was statistically significant. In conclusion, RSM is an effective and useful method for optimizing the medium components and investigating the interactive effects, and can provide valuable information for succinic acid scale-up fermentation using A. succinogenes strain BE-I.
基金supported by the Korea Institute of Industrial Technology Evaluation and Planning (ITEP) grant funded by the Ministry of Knowledge Economy (No.10032063)
文摘This paper describes the optimization of the impeller having splitters for a turbo blower.Two design variables,chord of splitter and pitch of splitter,are introduced to enhance the blower performance.Blower pressure and ef-ficiency are selected as an object function,and the optimization of the blower impeller is performed by a response surface method (RSM).Three-dimensional Navier-Stokes equations are introduced to analyze the internal flow of the blower and to find the value of the object function for each case.Throughout the shape optimization of the splitters attached to the impeller in the turbo blower,pressure and efficiency at the design flow condition are suc-cessively increased by 5.9 percent and 17.9 percent respectively based on the reference blower.The higher blower efficiency obtained by optimization of impeller having splitters is mainly caused by reducing the number of im-peller blades and optimal design of splitters in the blade passage while pressure increase keeps almost the same with the reference blower.For the object function of pressure,pressure increase is obtained at the design and off-design conditions while efficiency keeps higher compared to the reference blower.The enhancement of blow-er performance is due to the reduction of reverse and circulation flows in the blade passage.
文摘The propulsive efficiency of a plunging NACA0012 airfoil is maximized by means of a simple numerical optimization method based on the response surface methodology (RSM). The control parameters are the amplitude and the reduced frequency of the harmonic sinusoidal motion. The 2D unsteady laminar flow around the plunging airfoil is computed by solving the Navier-Stokes equations for three Reynolds number values (Re = 3.3× 10^3, 1.1×10^4, and 2.2 × 10^4). The Nelder-Mead algorithm is used to find the best control parameters leading to the optimal propulsive efficiency over the constructed response surfaces. It is found that, for a given efficiency level and regardless of the considered Re value, it is possible either to obtain high thrust by selecting a high oscillation frequency or to reduce the input power by adopting a low plunging amplitude. Key words: Plunging airfoil, Propulsive efficiency, Optimization, Response surface methodology (RSM)