Supported by the National Natural Science Foundation of China(11204001,11174004);Anhui Provincial Natural Science Foundation(2013KJS030026,1208085QA07,1308085MA04);the Higher Educational Natural Science Foundation of Anhui Province(2013KJT010021,KJ2013A031);Anhui University Scientific Research Fund(KYXL2012017,KYXL2013009,201410357005);"211 Project"of Anhui University(SZJYKC2013020,KYX12013009)