[Objectives] The content of astragaloside in Astragalus membranaceus(Fisch.) Bge.var.mongholicus(Bge.) Hisao from three different regions was determined.[Methods] Referring to the method recorded in the Chinese Pharma...[Objectives] The content of astragaloside in Astragalus membranaceus(Fisch.) Bge.var.mongholicus(Bge.) Hisao from three different regions was determined.[Methods] Referring to the method recorded in the Chinese Pharmacopoeia(2015 edition),the content of astragaloside IV in A.membranaceus was determined by HPLC.[Results] There were great differences in the astragaloside IV content of A.membranaceus among different regions.The content of astragaloside IV in A.membranaceus cultivated in Inner Mongolia was highest(0.155%),followed by that(0.143%) in A.membranaceus cultivated in Gansu,and the content of astragaloside IV in A.membranaceus cultivated in Shanxi was lowest(0.080%).The contents of astragaloside IV in A.membranaceus from different regions were all in line with the standard(not less than 0.040%) of Chinese Pharmacopoeia(2015 edition).[Conclusions]The content of astragaloside IV in A.membranaceus cultivated in three different regions met the medicinal standards.展开更多
The asymmetric ring-opening of epoxides with dithiophosphorus acids catalyzed by a (salen)Ti(Ⅳ) complex formed in situ from the reaction of Ti(OPr-i)4 and the chiral Schiff base derived from (1R,2R)-(+)-di...The asymmetric ring-opening of epoxides with dithiophosphorus acids catalyzed by a (salen)Ti(Ⅳ) complex formed in situ from the reaction of Ti(OPr-i)4 and the chiral Schiff base derived from (1R,2R)-(+)-diaminocyclohexane was realized. The resulting products were obtained with low to good enantioselectivity (up to 73% ee).展开更多
The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient ...The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient approximation as proposed by Perdew et al. is used for the energy exchange-correlation determination. The results show a metallic character of TiS2, and the plots of total and partial densities of states of TiS2 show the metallic character of the bonds and a strong hybridization between the states d of Ti and p of S below the Fermi energy. The optical properties of the material such as real and imaginary parts of dielectric constant (ε(w) = ε1(w) + iε2(w)), refractive index n(w), optical reflectivity R(w), for E / /x and E / /z are performed for the energy range of 0-.14 eV.展开更多
基金Supported by Tianjin Natural Science Fund(17JCYBJC29800)Tianjin Agricultural College Various Talents Funding Plan Project(J01009030702)+1 种基金Science and Technology Project in the Field of Social Development of Binhai New Area,TianjinAgricultural Science and Technology Plan Project of Baodi District,Tianjin(201838)
文摘[Objectives] The content of astragaloside in Astragalus membranaceus(Fisch.) Bge.var.mongholicus(Bge.) Hisao from three different regions was determined.[Methods] Referring to the method recorded in the Chinese Pharmacopoeia(2015 edition),the content of astragaloside IV in A.membranaceus was determined by HPLC.[Results] There were great differences in the astragaloside IV content of A.membranaceus among different regions.The content of astragaloside IV in A.membranaceus cultivated in Inner Mongolia was highest(0.155%),followed by that(0.143%) in A.membranaceus cultivated in Gansu,and the content of astragaloside IV in A.membranaceus cultivated in Shanxi was lowest(0.080%).The contents of astragaloside IV in A.membranaceus from different regions were all in line with the standard(not less than 0.040%) of Chinese Pharmacopoeia(2015 edition).[Conclusions]The content of astragaloside IV in A.membranaceus cultivated in three different regions met the medicinal standards.
基金the National Natural Science Foundation of China(No.20472033)the Ph.D Programs of Ministry of Education of China for generous financial support for our programs.
文摘The asymmetric ring-opening of epoxides with dithiophosphorus acids catalyzed by a (salen)Ti(Ⅳ) complex formed in situ from the reaction of Ti(OPr-i)4 and the chiral Schiff base derived from (1R,2R)-(+)-diaminocyclohexane was realized. The resulting products were obtained with low to good enantioselectivity (up to 73% ee).
文摘The electronic and optical properties of TiS2 are studied of density functional theory. A linearized and augmented by using an ab-initio calculation within the frame plane wave basis set with the generalized gradient approximation as proposed by Perdew et al. is used for the energy exchange-correlation determination. The results show a metallic character of TiS2, and the plots of total and partial densities of states of TiS2 show the metallic character of the bonds and a strong hybridization between the states d of Ti and p of S below the Fermi energy. The optical properties of the material such as real and imaginary parts of dielectric constant (ε(w) = ε1(w) + iε2(w)), refractive index n(w), optical reflectivity R(w), for E / /x and E / /z are performed for the energy range of 0-.14 eV.