基金supported by the National Natural Science Foundation of China (10771095)the Guangxi Science Foundation(0832107,0991102)the Scientific Research Foundation of Guangxi Educational Committee (200707LX233)
基金Supported by National Natural Science Foundation(11161006)Guan-gxi Natural Science Foundation(2010GXNSFB013048,2011GXNSFA018139)Scientific Research Foundation of Guangxi Educational Committee(201012MS140)
