1. State Key Laboratory of High-effciency Utilization of Coal and Green Chemical Engineering, College of Chemistry & Chemical Engineering, Ningxia University, Yinchuan 750021, China
2. National Measurement and Testing Center for Coal Chemical Industry, Ningxia Academy of Metrology & Quality Inspection, Yinchuan 750411, Ningxia, China
3. School of Materials and New Energy, Ningxia University, Yinchuan 750021, Ningxia, China