Supported by National Natural Science Foundation of China (50975301, 50942021, 11074314);Science and Technology Key Foundation of Chongqing (CSTC, 2009AC4045, 2010C6072);the Third Stage of “211” Innovative Talent Training Project (S-09109);Sharing Fund of Large-Scale Equipment of Chongqing University (2010063072, 2010121556)