1. School of Chemistry and Chemical Engineering; Hunan University of Science and Technology, Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education; Xiangtan 411201 People's Republic of China
2. State Key Laboratory of Powder Metallurgy; Central South University; Changsha 410083 People's Republic of China
3. Hunan Province Key Laboratory of Coal Resources Clean-utilization and Mine Environment Protection; Xiangtan 411201 People's Republic of China