收稿日期: 2019−03−04; 录用日期: 2019−07−03. †通信作者. E-mail: chinarenteng@163.com; Tel.: +86 15111234566. 本文责任编委: 王凌. 国家自然科学基金项目(61773120, 61873328), 国家社会科学基金项目(15BGL083), 湖南省社科基金重点委托项目(15WTB23)资助. Supported by the National Natural Science Foundation of China (61773120, 61873328), the National Social Science Foundation of China (15BGL083) and the Social Science Foundation of Hunan Province, China (15WTB23).
Supported by the National Natural Science Foundation of China (61773120, 61873328), the National Social Science Foundation of China (15BGL083) and the Social Science Foundation of Hunan Province, China (15WTB23).