Funding for this research was provided by:
Program for the Outstanding Young Talents of Hebei Province (YGZ)
Cultivation project of National Engineering Technology Center (2017B090903008)
Text and Data Mining valid from 2019-05-28
Received: 7 February 2019
Accepted: 9 May 2019
First Online: 28 May 2019
: The authors declare that they have no competing interests.
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