1. Xi'an Key Laboratory of Advanced Photo-Electronics Materials and Energy Conversion Device, School of Science, Xijing University , Xi'an , Shaanxi 710123 , China
2. Newspaper Office, China National Pulp and Paper Research Institute , Beijing 100102 , China
3. College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology , Xi'an , Shaanxi 710021 , China