1. School of Mechanical and Electrical Engineering Research Institute of Membrane Separation Technology of Shaanxi Province Xi'an University of Architecture and Technology Xi'an 710055 P. R. China
2. Salt Lake Chemical Engineering Research Complex Qinghai University Xining 810016 P. R. China
3. Key Laboratory of Materials Physics Centre for Environmental and Energy Nanomaterials Institute of Solid State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 P. R. China
4. Science Island Branch of Graduate School University of Science and Technology of China Hefei 230026 P. R. China
5. Department of Mechanical Engineering The University of Hong Kong Pokfulam Road Hong Kong 999077 China