Projects(21376031,21075011)supported by the National Natural Science Foundation of China; Project(2012GK3058)supported by the Foundation of Hunan Provincial Science and Technology Department,China; Project supported by the Postdoctoral Science Foundation of Central South University,China; Project(2014CL01)supported by the Foundation of Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation,China; Project supported by the Innovation Experiment Program for University Students of Changsha University of Science and Technology,China;