Funding for this research was provided by:
National Natural Science Foundation of China (31300054)
Youth Fund of the Natural Science Foundation of Jiangsu Province of China (BK20130228)
Grants from Natural Science Foundation of Xuzhou city (KC15N0014)
Postgraduate Research and Innovation Plan Project of Jiangsu Normal University (2016YZD019)
Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)