1. Faculty of Mathematics and Physics, Huaiyin Institute of Technology, Huaian 223003, China
2. Department of Mathematics, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
3. College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao 266590, China
4. School of Mathematics and Physics, Yancheng Institute of Technology, Yancheng 224051, China
5. School of Mathematics and Physics, Anhui University of Technology, Ma’anshan 243002, China