Supported by the National Natural Science Foundation of China(61070131);the Natural Science Research Programme of the Education Department of Anhui Province under Grant(KJ2009B113,KJ2010B270);the Excellent Youth Scholars of Ministry of the Education Department of Anhui Province(2009SQRZ189);the West Anhui University(WXYQ1305)
Supported by the National Natural Science Foundation of China (10901003);the Key Project of Chinese Ministry of Education (211077);the Anhui Provincial Natural Science Foundation(1208085MA11)