1. Tianjin Key Lab of Biomass Waste Utilization, School of Environmental Science and Engineering, Key Laboratory of Efficient Utilization of Low and Medium Grade Energy (Ministry of Education), Tianjin University, Tianjin 300072, China
2. Department of Energy Technology, Aalborg University, DK-9220 Aalborg East, Denmark
3. School of Science, Tibet University, Lhasa 850012, China