1. Key Laboratory of Bio-based Material Science & Technology, and College of Materials Science and Engineering, Northeast Forestry University, Harbin, Heilongjiang 150040, P.R. China
2. Engineering Research Center of Advanced Wooden Materials, Ministry of Education, Northeast Forestry University, Harbin, Heilongjiang 150040, P.R. China
3. Department of Chemical and Materials Engineering, University of Alberta, 9211-116 Street NW, Edmonton, Alberta T6G 1H9, Canada