湖南省教育厅科学研究重点项目14A088;湖南师范大学青年优秀人才培养计划项目2013YX07;国家自然科学基金No.41201135 Supported by the Key Project of Ministry of Education of Hunan Province14A088;the Training Program for the Distinguished Young Talents in Hunan Normal University2013YX07;the National Natural Science Foundation of China41201135