Supported by the Natural Science Foundation of Hunan Province ( 0 0 JJYZ0 110 ) and Scientific ResearchFund of Hunan Provincial Education Department( 0 1C0 2 2 )
Supported by the Natural Science Foundation of Hunan Province(0 0 JJY2 0 1 1 0 ) and Scientific Re-search Fund of Hunan Provincial Education Department(0 1 C0 2 2