An accurate theoretical study on the MgH radical is reported by adopting the high-level relativistic MRCI＋Q method with a quintuple-zeta quality basis set. The reliable potential energy curves of the five A-S states ...An accurate theoretical study on the MgH radical is reported by adopting the high-level relativistic MRCI＋Q method with a quintuple-zeta quality basis set. The reliable potential energy curves of the five A-S states of MgH are derived. Then the associated spectroscopic parameters are determined and found to be in good accordance with the available experimental results. The permanent dipole moments （PDMs） and the spin-orbit （SO） matrix elements of A-S states are computed. The results show that the abrupt changes of PDMs and SO matrix elements are attributed to the variations of electronic configurations at the avoided crossing point. The SOC effect leads to the five A-S states split into ten Ω states and results in the double potential well of （2）1//2 state. Finally, the transition properties from the （2）1//2, （1）3//2 and （3）1//2 states to the ground state X2∑＋1//2 transitions are obtained, including the transition dipole moments, Franck-Condon factors and radiative lifetimes.展开更多
Let α be a nonzero endomorphism of a ring R, n be a positive integer and T_n（R, α） be the skew triangular matrix ring. We show that some properties related to nilpotent elements of R are inherited by T_n（R, α）....Let α be a nonzero endomorphism of a ring R, n be a positive integer and T_n（R, α） be the skew triangular matrix ring. We show that some properties related to nilpotent elements of R are inherited by T_n（R, α）. Meanwhile, we determine the strongly prime radical, generalized prime radical and Behrens radical of the ring R[x; α]/（x^n）, where R[x; α] is the skew polynomial ring.展开更多
Xiangxi flavor vinegar（XV） is one of Hunan Province＇s traditional fermented vinegars.It is produced from herb,rice,and spring water with spontaneous liquid-state fermentation techniques.In this study,we investigate...Xiangxi flavor vinegar（XV） is one of Hunan Province＇s traditional fermented vinegars.It is produced from herb,rice,and spring water with spontaneous liquid-state fermentation techniques.In this study,we investigated the antioxidant property of XV by analyzing its antioxidant compounds,its free radical scavenging property in vitro and in vivo,and its effects on antioxidant enzyme activity and apoptosis in Caenorhabditis elegans.The results showed that XV is rich in antioxidants.In particular,ligustrazine reached 6.431 μg/ml.The in vitro 2,2-diphenyl-1-picrylhydrazyl free radical（DPPH＊）,hydroxyl radical（＊OH）,and superoxide anion radical（O2^（＊-）） scavenging rates of XV were 95.85%,97.22%,and 63.33%,respectively.The reactive oxygen species（ROS） content in XV-treated C.elegans decreased significantly（P0.01） compared to the control group.Giutathione peroxidase（GSH-Px）,superoxide dismutase（SOD）,and catalase（CAT） activities were remarkably increased（P0.01） in C.elegans after XV treatment.In addition,XV could upreguiate CED-9 protein expression and downreguiate CED-3 protein expression in C.elegans.These results prove that XV is rich in antioxidants and scavenges radicals in vitro efficiently.XV inhibits apoptosis in C.elegans probably by scavenging ROS and increasing the activities of its antioxidant enzymes.展开更多
Inspired by the photoprotection, radical scavenging of melanin together with versatile adhesive ability of mussel proteins, polydopamine（PDA） nanoparticles were successfully prepared and incorporated into environmen...Inspired by the photoprotection, radical scavenging of melanin together with versatile adhesive ability of mussel proteins, polydopamine（PDA） nanoparticles were successfully prepared and incorporated into environmentally friendly polymer, poly（propylene carbonate）（PPC） via solvent blending. The prepared composites exhibited excellent thermal stability in air and nitrogen atmosphere and extraordinary mechanical properties. The composites displayed eminent increase of temperature at 5% weight loss（T5%） by 30-100 K with 0.3 wt%-2.0 wt% loadings, meanwhile, the tensile strength and Young＇s modulus were significantly improved from 11.5 MPa and 553.7 MPa to 40.5 MPa and 2411.2 MPa, respectively. The kinetic calculation indicated that improvement of T5% is presumably derived from suppressing chain-end unzipping. The glass transition temperature（Tg） of the PPC/PDA composites increased by 8-10 K. This is probably due to hydrogen bonding interaction since the abundant proton donors along PDA chains would interact with proton acceptors like C = O and C―O―C in PPC which would cause restriction of segmental motion of PPC chains.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11564019,11574114,11147158,91221301 and 11264020the Natural Science Foundation of Jilin Province under Grant No 20150101003JC
文摘An accurate theoretical study on the MgH radical is reported by adopting the high-level relativistic MRCI＋Q method with a quintuple-zeta quality basis set. The reliable potential energy curves of the five A-S states of MgH are derived. Then the associated spectroscopic parameters are determined and found to be in good accordance with the available experimental results. The permanent dipole moments （PDMs） and the spin-orbit （SO） matrix elements of A-S states are computed. The results show that the abrupt changes of PDMs and SO matrix elements are attributed to the variations of electronic configurations at the avoided crossing point. The SOC effect leads to the five A-S states split into ten Ω states and results in the double potential well of （2）1//2 state. Finally, the transition properties from the （2）1//2, （1）3//2 and （3）1//2 states to the ground state X2∑＋1//2 transitions are obtained, including the transition dipole moments, Franck-Condon factors and radiative lifetimes.
文摘Let α be a nonzero endomorphism of a ring R, n be a positive integer and T_n（R, α） be the skew triangular matrix ring. We show that some properties related to nilpotent elements of R are inherited by T_n（R, α）. Meanwhile, we determine the strongly prime radical, generalized prime radical and Behrens radical of the ring R[x; α]/（x^n）, where R[x; α] is the skew polynomial ring.
基金supported by the College of Food Science and Technology,Hunan Agricultural University,China
文摘Xiangxi flavor vinegar（XV） is one of Hunan Province＇s traditional fermented vinegars.It is produced from herb,rice,and spring water with spontaneous liquid-state fermentation techniques.In this study,we investigated the antioxidant property of XV by analyzing its antioxidant compounds,its free radical scavenging property in vitro and in vivo,and its effects on antioxidant enzyme activity and apoptosis in Caenorhabditis elegans.The results showed that XV is rich in antioxidants.In particular,ligustrazine reached 6.431 μg/ml.The in vitro 2,2-diphenyl-1-picrylhydrazyl free radical（DPPH＊）,hydroxyl radical（＊OH）,and superoxide anion radical（O2^（＊-）） scavenging rates of XV were 95.85%,97.22%,and 63.33%,respectively.The reactive oxygen species（ROS） content in XV-treated C.elegans decreased significantly（P0.01） compared to the control group.Giutathione peroxidase（GSH-Px）,superoxide dismutase（SOD）,and catalase（CAT） activities were remarkably increased（P0.01） in C.elegans after XV treatment.In addition,XV could upreguiate CED-9 protein expression and downreguiate CED-3 protein expression in C.elegans.These results prove that XV is rich in antioxidants and scavenges radicals in vitro efficiently.XV inhibits apoptosis in C.elegans probably by scavenging ROS and increasing the activities of its antioxidant enzymes.
基金financially supported by the National Natural Science Foundation of China(Nos.51173112 and 21274095)
文摘Inspired by the photoprotection, radical scavenging of melanin together with versatile adhesive ability of mussel proteins, polydopamine（PDA） nanoparticles were successfully prepared and incorporated into environmentally friendly polymer, poly（propylene carbonate）（PPC） via solvent blending. The prepared composites exhibited excellent thermal stability in air and nitrogen atmosphere and extraordinary mechanical properties. The composites displayed eminent increase of temperature at 5% weight loss（T5%） by 30-100 K with 0.3 wt%-2.0 wt% loadings, meanwhile, the tensile strength and Young＇s modulus were significantly improved from 11.5 MPa and 553.7 MPa to 40.5 MPa and 2411.2 MPa, respectively. The kinetic calculation indicated that improvement of T5% is presumably derived from suppressing chain-end unzipping. The glass transition temperature（Tg） of the PPC/PDA composites increased by 8-10 K. This is probably due to hydrogen bonding interaction since the abundant proton donors along PDA chains would interact with proton acceptors like C = O and C―O―C in PPC which would cause restriction of segmental motion of PPC chains.
