National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [20775010, 21075011]; National High Technology Research and Development Program of ChinaNational High Technology Research and Development Program of China [2008AA05Z405]; Hunan Provincial Natural Science Foundation, ChinaNatural Science Foundation of Hunan Province [09JJ3016]; Hunan Provincial Education Department, ChinaHunan Provincial Education Department [09C066]; Foundation of Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, China [2010CL01]