Chlorophylls were extracted by using ultrasonic from Spirulina platensis.Single factor examination and response surface analysis experiments were adopted to investigate the effects of extraction time,extraction solven...Chlorophylls were extracted by using ultrasonic from Spirulina platensis.Single factor examination and response surface analysis experiments were adopted to investigate the effects of extraction time,extraction solvent,solvent concentration,ratio of liquid to solid and extraction grade.The results showed that the optimal process parameters for this method were:extraction time of 56.5 min,ethanol concentration of 48.3%(vol) of ethanol/acetone solvent,and ratio of liquid to solid of 7.9 ml·g-1.The optimized chlorophylls extraction yield was 1.28%.The comparison experimental results indicated that the yield of chlorophylls by ultrasonic extraction was higher than that obtained from conventional solvent extraction.展开更多
Three-dimensional simulations of ferroelectric hysteresis and butterfly loops are carried out based on solving the time dependent Ginzburg-Landau equations using a finite volume method. The influence of externally mec...Three-dimensional simulations of ferroelectric hysteresis and butterfly loops are carried out based on solving the time dependent Ginzburg-Landau equations using a finite volume method. The influence of externally mechanical loadings with a tensile strain and a compressive strain on the hysteresis and butterfly loops is studied numerically. Different from the traditional finite element and finite difference methods, the finite volume method is applicable to simulate the ferroelectric phase transitions and properties of ferroelectric materials even for more realistic and physical problems.展开更多
文摘Chlorophylls were extracted by using ultrasonic from Spirulina platensis.Single factor examination and response surface analysis experiments were adopted to investigate the effects of extraction time,extraction solvent,solvent concentration,ratio of liquid to solid and extraction grade.The results showed that the optimal process parameters for this method were:extraction time of 56.5 min,ethanol concentration of 48.3%(vol) of ethanol/acetone solvent,and ratio of liquid to solid of 7.9 ml·g-1.The optimized chlorophylls extraction yield was 1.28%.The comparison experimental results indicated that the yield of chlorophylls by ultrasonic extraction was higher than that obtained from conventional solvent extraction.
基金Supported by the Research Starting Funds for Imported Talents of Ningxia University under Grant No BQD2012011
文摘Three-dimensional simulations of ferroelectric hysteresis and butterfly loops are carried out based on solving the time dependent Ginzburg-Landau equations using a finite volume method. The influence of externally mechanical loadings with a tensile strain and a compressive strain on the hysteresis and butterfly loops is studied numerically. Different from the traditional finite element and finite difference methods, the finite volume method is applicable to simulate the ferroelectric phase transitions and properties of ferroelectric materials even for more realistic and physical problems.
