The ground-state energy and its derivate of the acoustic polaron in free-standing slab are calculated by using the Huybrechts-like variational approach. The criteria for presence of the selftrapping transition of the ...The ground-state energy and its derivate of the acoustic polaron in free-standing slab are calculated by using the Huybrechts-like variational approach. The criteria for presence of the selftrapping transition of the acoustic polaron in free-standing slabs are determined qualitatively. The critical coupling constant for the discontinuous transition from a quasi-free state to a trapped state of the acoustic polaron in free-standing slabs tends to shift toward the weaker electronphonon coupling with the increasing cutoff wave-vector. Detailed numerical results confirm that the self-trapping transition of holes is expected to occur in the free-standing slabs of wide-bandgap semi-conductors.展开更多
Hollow core slabs are becoming of increasing interest as the construction industry attempts to minimise the impact of its activities on the environment. By forming voids in the interior of a concrete slab, the amount ...Hollow core slabs are becoming of increasing interest as the construction industry attempts to minimise the impact of its activities on the environment. By forming voids in the interior of a concrete slab, the amount of concrete used can be reduced without significantly altering the capacity of the structure. In this study, we examined the inner force transfer mechanism of a column-supported cast-in-situ hollow core slab using finite element analysis. Both a hollow core slab and the corresponding solid slab were analysed using ANSYS and the results were compared. The orientation of the tube fillers causes the stiffness of the hollow slab to be orthotropic, potentially changing the distribution of load carried in the two orthogonal directions. Both the cross-section’s moments in the column strip and near the columns in the hollow core slab become larger than that in the solid floor. As well, the cross-section’s stiffness along the tube arrangement direction is larger than that of the radial cross-section, which causes the direction along the hole of the hollow core slab to carry more moment than the radial direction. The conversion factors of the two directions are proposed from the comparison for four typical areas of the hollow core slab, as are the moment distribution coefficients.展开更多
文摘The ground-state energy and its derivate of the acoustic polaron in free-standing slab are calculated by using the Huybrechts-like variational approach. The criteria for presence of the selftrapping transition of the acoustic polaron in free-standing slabs are determined qualitatively. The critical coupling constant for the discontinuous transition from a quasi-free state to a trapped state of the acoustic polaron in free-standing slabs tends to shift toward the weaker electronphonon coupling with the increasing cutoff wave-vector. Detailed numerical results confirm that the self-trapping transition of holes is expected to occur in the free-standing slabs of wide-bandgap semi-conductors.
基金Project supported by the Australian Research Council Research Grant (No. DP0988940)the Natural Science Foundation of Jiangsu Province (No. BK2009394)+2 种基金the China Postdoctoral Science Foundation (No. 2011M500930)the Natural Science Surface Project of Jiangsu Provincial Universities (No. 11KJB560003)the Talent Introduction Fund of Nanjing Forestry University (No. 163050072)
文摘Hollow core slabs are becoming of increasing interest as the construction industry attempts to minimise the impact of its activities on the environment. By forming voids in the interior of a concrete slab, the amount of concrete used can be reduced without significantly altering the capacity of the structure. In this study, we examined the inner force transfer mechanism of a column-supported cast-in-situ hollow core slab using finite element analysis. Both a hollow core slab and the corresponding solid slab were analysed using ANSYS and the results were compared. The orientation of the tube fillers causes the stiffness of the hollow slab to be orthotropic, potentially changing the distribution of load carried in the two orthogonal directions. Both the cross-section’s moments in the column strip and near the columns in the hollow core slab become larger than that in the solid floor. As well, the cross-section’s stiffness along the tube arrangement direction is larger than that of the radial cross-section, which causes the direction along the hole of the hollow core slab to carry more moment than the radial direction. The conversion factors of the two directions are proposed from the comparison for four typical areas of the hollow core slab, as are the moment distribution coefficients.