Ferulic acid was obtained from rice hull with the microwave-assisted extraction method.The solubility data of trans-ferulic acid in 8 binary systems of water and organic solvents,such as methyl acetate,ethyl acetate,b...Ferulic acid was obtained from rice hull with the microwave-assisted extraction method.The solubility data of trans-ferulic acid in 8 binary systems of water and organic solvents,such as methyl acetate,ethyl acetate,butyl acetate,methanol,ethanol,dichloromethane and chloroform were measured from 273.15 K to 333.15 K.The empirical equation was adopted,and the solubilities calculated by the model were in good agreement with experimental data.展开更多
The structure of the low-temperature 4f^N→4f^N-15d excitation spectra of Eu^3＋ and Tb^3＋ doped in crystals LiYF4, YPO4 and CaF2 measured by van Pieterson et al. in 2002 was analyzed and assigned based on the simple...The structure of the low-temperature 4f^N→4f^N-15d excitation spectra of Eu^3＋ and Tb^3＋ doped in crystals LiYF4, YPO4 and CaF2 measured by van Pieterson et al. in 2002 was analyzed and assigned based on the simple model proposed by Duan and co-workers in the last few years. Some complemental discussion on effects of J-mixing on the f-d transition intensities for Eu^3＋ due to the f-electron crystal-field interaction Hcf（f）, which was ignored in the simple mod- el, was presented. Some previously unexplained peaks for Tb^3 ＋ were interpreted to be spin-forbidden transitions to higher 5d crystal-field levels, or assigned to be f→d excitations with the core 4f7 excited from ^8S to ^6P, ^6I and ^6D, respectively. It is shown that the main structure of 4f-Sd excitation spectra of Eu^3＋ and Tb^3＋ can be well interpreted with the simple model.展开更多
文摘Ferulic acid was obtained from rice hull with the microwave-assisted extraction method.The solubility data of trans-ferulic acid in 8 binary systems of water and organic solvents,such as methyl acetate,ethyl acetate,butyl acetate,methanol,ethanol,dichloromethane and chloroform were measured from 273.15 K to 333.15 K.The empirical equation was adopted,and the solubilities calculated by the model were in good agreement with experimental data.
文摘The structure of the low-temperature 4f^N→4f^N-15d excitation spectra of Eu^3＋ and Tb^3＋ doped in crystals LiYF4, YPO4 and CaF2 measured by van Pieterson et al. in 2002 was analyzed and assigned based on the simple model proposed by Duan and co-workers in the last few years. Some complemental discussion on effects of J-mixing on the f-d transition intensities for Eu^3＋ due to the f-electron crystal-field interaction Hcf（f）, which was ignored in the simple mod- el, was presented. Some previously unexplained peaks for Tb^3 ＋ were interpreted to be spin-forbidden transitions to higher 5d crystal-field levels, or assigned to be f→d excitations with the core 4f7 excited from ^8S to ^6P, ^6I and ^6D, respectively. It is shown that the main structure of 4f-Sd excitation spectra of Eu^3＋ and Tb^3＋ can be well interpreted with the simple model.
