国家自然科学基金50602029,61274067,60876045;上海市基础研究重点项目09JC1405900;上海大学课程建设项目批准号:B.08-0101-14-111资助的课题.* Project supported by the National Natural Science Foundation of ChinaGrant .50602029,61274067,60876045;the Shanghai Leading Basic Research Project of ChinaGrant 09JC1405900;the Curriculum Construction Project of Shanghai University, ChinaGrant B.08-0101-14-111