[Objective] The aim was to study the optimum extraction process of polysaccharide from chrysanthemum.[Method] By dint of orthogonal and single-factor experiments,the influences of microwave efficiency,extraction time,...[Objective] The aim was to study the optimum extraction process of polysaccharide from chrysanthemum.[Method] By dint of orthogonal and single-factor experiments,the influences of microwave efficiency,extraction time,and liquid ratio on the extraction rate of polysaccharides from chrysanthemum were studied.The optimum operation condition by microwave extraction method was determined and was compared with that by traditional extraction method.[Result] The optimum extraction conditions were:800 W,1:15(solid-liquid ratio),and 15 min.The polysaccharides extraction yield under such optimum condition was 5.59%.The extraction yield of impregnation was generally about 2.73%.[Conclusion] Compared with the traditional extraction method,the microwave extraction was simple,convenient,energy saving,and efficient,and was suitable for industrial extraction of polysaccharide.展开更多
MODIS-EVI time series data from 2000 to 2009 in Chongqing were selected for this study.By the use of best index slope extraction （BISE） method for cloud elimination,analysis on the change vector of EVI time series d...MODIS-EVI time series data from 2000 to 2009 in Chongqing were selected for this study.By the use of best index slope extraction （BISE） method for cloud elimination,analysis on the change vector of EVI time series data were conducted to investigate the EVI response on drought; then,four typical regions were selected to study the relationship between precipitation,temperature and EVI when the sever drought occurred in 2006; finally,based on the time series of vegetation condition index （VCI） and precipitation abnormity percentage,the temporal and spatial distributions of drought were studied.The results showed that,the EVI value of the summer in 2006 was significantly lower than the average EVI at the corresponding period of the other years in Chongqing.In addition,summer drought occurred mainly during the hot and dry weather.Except the southeast area,most of the other regions in Chongqing were all under severe drought.展开更多
基金Supported by Doctoral Initial Funding of Henan University of TCM(BSJJ2009-34)
文摘[Objective] The aim was to study the optimum extraction process of polysaccharide from chrysanthemum.[Method] By dint of orthogonal and single-factor experiments,the influences of microwave efficiency,extraction time,and liquid ratio on the extraction rate of polysaccharides from chrysanthemum were studied.The optimum operation condition by microwave extraction method was determined and was compared with that by traditional extraction method.[Result] The optimum extraction conditions were:800 W,1:15(solid-liquid ratio),and 15 min.The polysaccharides extraction yield under such optimum condition was 5.59%.The extraction yield of impregnation was generally about 2.73%.[Conclusion] Compared with the traditional extraction method,the microwave extraction was simple,convenient,energy saving,and efficient,and was suitable for industrial extraction of polysaccharide.
基金Supported by Foundation for Science and Technology Research Project of Chongqing (2009AC0125)Natural Science Foundation of Chongqing (2008BB1379)The Major Project of Ministry of Science and Technology," Science and Technology Action for Western Development" (2005BA901A01)~~
文摘MODIS-EVI time series data from 2000 to 2009 in Chongqing were selected for this study.By the use of best index slope extraction （BISE） method for cloud elimination,analysis on the change vector of EVI time series data were conducted to investigate the EVI response on drought; then,four typical regions were selected to study the relationship between precipitation,temperature and EVI when the sever drought occurred in 2006; finally,based on the time series of vegetation condition index （VCI） and precipitation abnormity percentage,the temporal and spatial distributions of drought were studied.The results showed that,the EVI value of the summer in 2006 was significantly lower than the average EVI at the corresponding period of the other years in Chongqing.In addition,summer drought occurred mainly during the hot and dry weather.Except the southeast area,most of the other regions in Chongqing were all under severe drought.
