Zhang, Tianyi
Chen, Geng
Zeng, Qingtian
Song, Ge
Li, Chao
Duan, Hua
Funding for this research was provided by:
the National Natural Science Foundation of China (No. 31671588, 61701284 and 61472229)
the Sci. & Tech. Development Fund of Shandong Province of China (No. 2016ZDJS02A11 and ZR2017MF027)
the Innovative Research Foundation of Qingdao (No.19-6-2-1-cg)
the Humanities and Social Science Research Project of the Ministry of Education (No.18YJAZH017)
the SDUST Research Fund (No. 2015TDJH102)
Article History
Received: 16 November 2019
Accepted: 13 March 2020
First Online: 5 April 2020
Competing interests
: The authors declare that they have no competing interests.