Funding for this research was provided by:
National Natural Science Foundation of China (61572295,61573212, 61272241)
Natural Science Foundation of Shandong Province of China (ZR2014FM031, ZR2013FQ014)
Shandong Province Independent Innovation Major Special Project (2015ZDXX0201B03)
Shandong Province key research and development plan (2015GGX101015, 2015GGX101007)
Fundamental Research Funds of Shandong University (2015JC031)
Received: 22 July 2018
Accepted: 5 September 2018
First Online: 24 September 2018
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