Using three different parameterized dark energy models, we reconstruct the properties of dark energy from the latest 397 Sne Ia, CMB and BAO with the present matter density, Ωm0, given prior. We find that, when Ωm0 is not small, for example, Ωm0 = 0.28 or 0.32, an evolving dark energy with a crossing of phantom divide line is favored and this conclusion seems to be model independent. We also find that the evolving properties of dark energy become more and more evident with the increase of Ωm0 given prior.
HUANG TieTie1,2,3, WU PuXun2,3 & YU HongWei2,3 1Department of Physics, Xiangnan College, Chenzhou 423000, China
The segregation effect of B on the [100](010) edge dislocation core in NiAl single crystals is investigated using the DMol method and the discrete variational method within the framework of density functional theory. The impurity segregation energy and the charge distribution are calculated. The effects of B on the dislocation motion are discussed. The results show that B prefers to segregate at the Center-Al dislocation core. Moreover, B forms strong bonding states with its neighboring host atoms, which may not be beneficial to the motion of the dislocation. Therefore, it can be expected that the strength of NiAl single crystals may be increased.
