Funding for this research was provided by:
National Natural Science Foundation of China (11371230)
National Natural Science Foundation of China (11501331)
National Natural Science Foundation of China (11561004)
SDUST Research Fund (2014TDJH102)
Shandong Provincial Natural Science Foundation, China (ZR2015AQ001)
Shandong Provincial Natural Science Foundation, China (BS2015SF002)
SDUST Innovation Fund for Graduate Students (SDKDYC170225)