1. School of Science, Tianjin University of Commerce, Tianjin 300134, P. R. China
2. Tianjin Yi-Sheng Offshore Engineering Co. Ltd., Tianjin 300400, P. R. China
3. Basic Department, Shaanxi Institute of Fashion Engineering, Shaanxi 712000, P. R. China
4. Department of Mathematics, College of Science, Taif University, Taif, Saudi Arabia
5. Tianjin Tianwei Chemical Engineering Co. Ltd., Tianjin 300400, P. R. China