Funding for this research was provided by:
National Natural Science Foundation of China (11601048)
National Natural Science Foundation of China (11571207)
Natural Science Foundation of Chongqing (cstc2016jcyjA0181)
Natural Science Foundation of Chongqing Normal University (16XYY24)
Natural Science Foundation of Shandong (ZR2018MA011)
the Tai’shan Scholar Engineering Construction Fund of Shandong Province of China. (NA)
Article History
Received: 19 April 2019
Accepted: 31 May 2019
First Online: 11 June 2019
Ethics approval and consent to participate
: Not applicable.
: The authors declare that they have no competing interests.
: Not applicable.