基金Project (51102056) supported by National Natural Science Foundation of ChinaProjects (2011GXNSFB018008, 2012GXNSFGA060002) supported by Guangxi Natural Science Foundation+2 种基金Project (2011no.40) supported by Program for Excellent Talents in Guangxi Higher Education InstitutionsProject (201012MS085) supported by Research Program of Guangxi Education DepartmentProject (2012M511975) supported by China Postdoctoral Science Foundation Funded