By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d<SUP>3</SUP...By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d<SUP>3</SUP> electronic configuration, the values of all the parameters in the expressions of thermal shift (TS) and thermal broadening (TB) due to EPI for the ground level, R level and R line of MgO:Cr<SUP>3+</SUP> have microscopically been evaluated; and then, TS and TB of R line and various contributions to them have uniformly been calculated. The results are in very good agreement with the experimental data. It is found that all the three terms of TS due to EPI are red shifts; the Raman term is the largest one, and the optical-branch term and neighbor-level term are important for TS; the contribution to TS from thermal expansion is blue shift, which is also important. The R-line TS of MgO:Cr<SUP>3+</SUP> comes from the first-order term of EPI. The elastic Raman scattering of acoustic phonons plays a dominant role in R-line TB of MgO:Cr<SUP>3+</SUP>. For both TS and TB, it is very important to take into account all the admixtures of basic wavefunctions within d<SUP>3</SUP> electronic configuration.展开更多
The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ PP ） blends has been investigated experimentally through Molan test, microscopic morphology, and ch...The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ PP ） blends has been investigated experimentally through Molan test, microscopic morphology, and chemical structure. Results show that the moderate R-SMA addition can promote reaction between anhydride in R-SMA and amino in PA6, and lead to a new PA6-g- R-SMA copolymer in the blends. Such PA6-g-R-SMA eopolymer in the blends can effectively reduce the interfaeial tension and PP particle size, and improve the compatibility of two immiscible phases in the blends. The crystallinity of PA6 in PA6/PP blends has greatly decreased by PP blends. The blends have the best comprehensive mechanical and thermal properties when the mass ratio of PA6/PP/ R-SMA is 90：10：2 to 90：10：4. The impact strength of the PA6/PP blends with the eompatibilizer is increased by more than 150 %.展开更多
The Chandrasekhar-Friedmann-Schutz （CFS） instabilities of r-modes for canonical neutron stars （1.4 Me） with rigid crusts are investigated by using an equation of state of asymmetric nuclear matter with super-soft ...The Chandrasekhar-Friedmann-Schutz （CFS） instabilities of r-modes for canonical neutron stars （1.4 Me） with rigid crusts are investigated by using an equation of state of asymmetric nuclear matter with super-soft symmetry energy, where the non-Newtonian gravity proposed in the grand unification theories is also considered. Constrained by the observations of the masses and the spin frequencies for neutron stars, the boundary of the r-mode instability window for a canonical neutron star is obtained, and the results show that the observed neutron stars are all outside the instability window, which is consistent with the theoretical expectation. In addition, an upper limit of the non-Newtonian gravity parameters is also given.展开更多
文摘By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d<SUP>3</SUP> electronic configuration, the values of all the parameters in the expressions of thermal shift (TS) and thermal broadening (TB) due to EPI for the ground level, R level and R line of MgO:Cr<SUP>3+</SUP> have microscopically been evaluated; and then, TS and TB of R line and various contributions to them have uniformly been calculated. The results are in very good agreement with the experimental data. It is found that all the three terms of TS due to EPI are red shifts; the Raman term is the largest one, and the optical-branch term and neighbor-level term are important for TS; the contribution to TS from thermal expansion is blue shift, which is also important. The R-line TS of MgO:Cr<SUP>3+</SUP> comes from the first-order term of EPI. The elastic Raman scattering of acoustic phonons plays a dominant role in R-line TB of MgO:Cr<SUP>3+</SUP>. For both TS and TB, it is very important to take into account all the admixtures of basic wavefunctions within d<SUP>3</SUP> electronic configuration.
基金Science and Technology Program from Jiangxi Provincial Department of Education,China (No. CJJ10377)
文摘The effect of R-styrene-maleic anhydride copolymer （R- SMA） compatibilzation on Nylon 6 （ PA6 ）/polypropylene （ PP ） blends has been investigated experimentally through Molan test, microscopic morphology, and chemical structure. Results show that the moderate R-SMA addition can promote reaction between anhydride in R-SMA and amino in PA6, and lead to a new PA6-g- R-SMA copolymer in the blends. Such PA6-g-R-SMA eopolymer in the blends can effectively reduce the interfaeial tension and PP particle size, and improve the compatibility of two immiscible phases in the blends. The crystallinity of PA6 in PA6/PP blends has greatly decreased by PP blends. The blends have the best comprehensive mechanical and thermal properties when the mass ratio of PA6/PP/ R-SMA is 90：10：2 to 90：10：4. The impact strength of the PA6/PP blends with the eompatibilizer is increased by more than 150 %.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10947023 and 11275073the Fundamental Research Funds for the Central Universities under Grant No. 2012ZZ0079the Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘The Chandrasekhar-Friedmann-Schutz （CFS） instabilities of r-modes for canonical neutron stars （1.4 Me） with rigid crusts are investigated by using an equation of state of asymmetric nuclear matter with super-soft symmetry energy, where the non-Newtonian gravity proposed in the grand unification theories is also considered. Constrained by the observations of the masses and the spin frequencies for neutron stars, the boundary of the r-mode instability window for a canonical neutron star is obtained, and the results show that the observed neutron stars are all outside the instability window, which is consistent with the theoretical expectation. In addition, an upper limit of the non-Newtonian gravity parameters is also given.
