[Objectives] To increase the survival rate of tissue culture seedlings of Dendrobium officinale,and optimize the conditions of rooting medium by the response surface methodology( RSM). [Methods]The effects of 6-BA con...[Objectives] To increase the survival rate of tissue culture seedlings of Dendrobium officinale,and optimize the conditions of rooting medium by the response surface methodology( RSM). [Methods]The effects of 6-BA concentration,NAA concentration,potato amount and the amount of mashed banana on the growth of seedlings were determined by single factor experiment and were analyzed by Box-Behnken design and response surface methodology. [Results]The optimal culture conditions: rooting medium 1/2 MS + 6-BA 0. 24 mg/L + mashed banana 87. 63 g/L + potato 89. 30 g/L + NAA 0. 52 mg/L + sucrose 20. 0 g/L + activated carbon 4. 0 g/L + agar 7. 0 g/L,p H 5. 8,and light intensity 2 000 Lx. [Conclusions]The model established by response surface methodology has a good predictability and could be used to optimize the conditions of tissue culture and rooting medium of D. officinale.展开更多
In the present work, the response surface method software was used with five measurement levels with three factors.These were applied for the optimization of operating parameters that affected gas separation performan...In the present work, the response surface method software was used with five measurement levels with three factors.These were applied for the optimization of operating parameters that affected gas separation performance of polyurethane–zeolite 3A, ZSM-5 mixed matrix membranes.The basis of the experiments was a rotatable central composite design(CCD).The three independent variables studied were: zeolite content(0–24 wt%), operating temperature(25–45 ℃) and operating pressure(0.2–0.1 MPa).The effects of these three variables on the selectivity and permeability membranes were studied by the analysis of variance(ANOVA).Optimal conditions for the enhancement of gas separation performances of polyurethane–3A zeolite were found to be 18 wt%, 30 ℃ and 0.8 MPa respectively.Under these conditions, the permeabilities of carbon dioxide, methane, oxygen and nitrogen gases were measured at 138.4, 22.9, 15.7 and 6.4 Barrer respectively while the CO_2/CH_4, CO_2/N_2 and O_2/N_2 selectivities were 5.8, 22.5 and 2.5, respectively.Also, the optimal conditions for improvement of the gas separation performance of polyurethane–ZSM 5 were found to be 15.64 wt%, 30 ℃ and 4 bar.The permeabilities of these four gases(i.e.carbon dioxide, methane, oxygen and nitrogen) were 164.7, 21.2, 21.5 and 8.1 Barrer while the CO_2/CH_4, CO_2/N_2 and O_2/N_2 selectivities were 7.8, 20.6 and 2.7 respectively.展开更多
The production of cellulase in Bacillus amyloliquefaciens UNPDV-22 was optimized using response surface methodology （RSM）. Central composite design （CCD） was used to study the interactive effect of culture conditi...The production of cellulase in Bacillus amyloliquefaciens UNPDV-22 was optimized using response surface methodology （RSM）. Central composite design （CCD） was used to study the interactive effect of culture conditions （temperature, pH, and inoculum） on cellulase activity. Results suggested that temperature and pH all have significant impact on cellulase production. The use of RSM resulted in a 96% increase in the cellulase activity over the control of non-optimized basal medium. Optimum cellulase production of 13 U/mL was obtained at a temperature of 42.24 ℃, pH of 5.25, and inoculum size of 4.95% （v/v） in a fermentation medium containing wheat bran, soybean meal and malt dextrin as major nutritional factors.展开更多
The water content of proton exchange membrane fuel cells(PEMFCs)affects the transport of reactants and the conductivity of the membrane.Effective water management measures can improve the performance and extend the li...The water content of proton exchange membrane fuel cells(PEMFCs)affects the transport of reactants and the conductivity of the membrane.Effective water management measures can improve the performance and extend the lifespan of the fuel cell.The water management state of the stack is influenced by various external operating conditions,and optimizing the combination of these conditions can improve the water management state within the stack.Considering that the stack's internal resistance can reflect its water management state,this study first establishes an internal resistance-operating condition model that considers the coupling effect of temperature and humidity to determine the variation trend of total resistance and stack humidity with single-factor operating conditions.Subsequently,the water management state optimization method based on the ANN-HGPSO algorithm is proposed,which not only quantitatively evaluates the influence weights of different operating conditions on the stack's internal resistance but also efficiently and accurately obtains the optimal combination of five operating conditions:working temperature,anode gas pressure,cathode gas pressure,anode gas humidity,and cathode gas humidity to achieve the optimal water management state in the stack,within the entire range of current densities.Finally,the response surface experimental results of the stack also validate the effectiveness and accuracy of the ANN-HGPSO algorithm.The method mentioned in this article can provide effective strategies for efficient water management and output performance optimization control of PEMFC stacks.展开更多
基金Supported by Scientific and Technological Planning Project of Pu'er City of Yunnan Province(2012kj007)
文摘[Objectives] To increase the survival rate of tissue culture seedlings of Dendrobium officinale,and optimize the conditions of rooting medium by the response surface methodology( RSM). [Methods]The effects of 6-BA concentration,NAA concentration,potato amount and the amount of mashed banana on the growth of seedlings were determined by single factor experiment and were analyzed by Box-Behnken design and response surface methodology. [Results]The optimal culture conditions: rooting medium 1/2 MS + 6-BA 0. 24 mg/L + mashed banana 87. 63 g/L + potato 89. 30 g/L + NAA 0. 52 mg/L + sucrose 20. 0 g/L + activated carbon 4. 0 g/L + agar 7. 0 g/L,p H 5. 8,and light intensity 2 000 Lx. [Conclusions]The model established by response surface methodology has a good predictability and could be used to optimize the conditions of tissue culture and rooting medium of D. officinale.
文摘In the present work, the response surface method software was used with five measurement levels with three factors.These were applied for the optimization of operating parameters that affected gas separation performance of polyurethane–zeolite 3A, ZSM-5 mixed matrix membranes.The basis of the experiments was a rotatable central composite design(CCD).The three independent variables studied were: zeolite content(0–24 wt%), operating temperature(25–45 ℃) and operating pressure(0.2–0.1 MPa).The effects of these three variables on the selectivity and permeability membranes were studied by the analysis of variance(ANOVA).Optimal conditions for the enhancement of gas separation performances of polyurethane–3A zeolite were found to be 18 wt%, 30 ℃ and 0.8 MPa respectively.Under these conditions, the permeabilities of carbon dioxide, methane, oxygen and nitrogen gases were measured at 138.4, 22.9, 15.7 and 6.4 Barrer respectively while the CO_2/CH_4, CO_2/N_2 and O_2/N_2 selectivities were 5.8, 22.5 and 2.5, respectively.Also, the optimal conditions for improvement of the gas separation performance of polyurethane–ZSM 5 were found to be 15.64 wt%, 30 ℃ and 4 bar.The permeabilities of these four gases(i.e.carbon dioxide, methane, oxygen and nitrogen) were 164.7, 21.2, 21.5 and 8.1 Barrer while the CO_2/CH_4, CO_2/N_2 and O_2/N_2 selectivities were 7.8, 20.6 and 2.7 respectively.
文摘The production of cellulase in Bacillus amyloliquefaciens UNPDV-22 was optimized using response surface methodology （RSM）. Central composite design （CCD） was used to study the interactive effect of culture conditions （temperature, pH, and inoculum） on cellulase activity. Results suggested that temperature and pH all have significant impact on cellulase production. The use of RSM resulted in a 96% increase in the cellulase activity over the control of non-optimized basal medium. Optimum cellulase production of 13 U/mL was obtained at a temperature of 42.24 ℃, pH of 5.25, and inoculum size of 4.95% （v/v） in a fermentation medium containing wheat bran, soybean meal and malt dextrin as major nutritional factors.
基金supported by the National Key Research and Devel-opment Project of China(2020YFB1506802)the Key Research and Development Project of Guangdong Province(2020B0909040004).
文摘The water content of proton exchange membrane fuel cells(PEMFCs)affects the transport of reactants and the conductivity of the membrane.Effective water management measures can improve the performance and extend the lifespan of the fuel cell.The water management state of the stack is influenced by various external operating conditions,and optimizing the combination of these conditions can improve the water management state within the stack.Considering that the stack's internal resistance can reflect its water management state,this study first establishes an internal resistance-operating condition model that considers the coupling effect of temperature and humidity to determine the variation trend of total resistance and stack humidity with single-factor operating conditions.Subsequently,the water management state optimization method based on the ANN-HGPSO algorithm is proposed,which not only quantitatively evaluates the influence weights of different operating conditions on the stack's internal resistance but also efficiently and accurately obtains the optimal combination of five operating conditions:working temperature,anode gas pressure,cathode gas pressure,anode gas humidity,and cathode gas humidity to achieve the optimal water management state in the stack,within the entire range of current densities.Finally,the response surface experimental results of the stack also validate the effectiveness and accuracy of the ANN-HGPSO algorithm.The method mentioned in this article can provide effective strategies for efficient water management and output performance optimization control of PEMFC stacks.
