1. School of Mine Safety, North China Institute of Science and Technology, 468 Xueyuan Street, Sanhe, Langfang 065201, China
2. School of Science, North China Institute of Science and Technology, 468 Xueyuan Street, Sanhe, Langfang 065201, China
3. School of Safety Engineering, North China Institute of Science and Technology, 468 Xueyuan Street, Sanhe, Langfang 065201, China