国家自然科学基金No.21007036;山西省自然科学基金No.2012011036-6;山西省高校优秀青年学术带头人支持计划No.20120303 Supported by the National Natural Science Foundation of China No.21007036,the Natural Science Foundation of Shanxi Province No.2012011036-6 and the Program for the Top Young Academic Leaders of Higher Learning Institutions of Shanxi No.20120303