Funding for this research was provided by:
National Natural Science Foundation of China (51705070)
Science Foundation Ireland (15/RP/B3208)
Fundamental Research Funds for the Central Universities (N172304037)
Natural Science Foundation of Hebei Province (E2018501038)
Article History
Received: 7 August 2018
Accepted: 19 February 2019
First Online: 12 March 2019