基金supported by the National Natural Science Foundation of China(Grant No. 61005052)the National 863 High Technology Research and Development Program of China(Grant No. 2006AA010107 and 2006AA010108)+1 种基金the Natural Science Foundation of Fujian Province(Grant No. 2006J0043)the Fund of Key Research Project of Fujian Province(Grant No. 2006H0038)