1. CAS Key Laboratory of Urban Pollutant Conversion Department of Environmental Science and Engineering University of Science and Technology of China Hefei 230026 P. R. China
2. Institute of Textiles and Clothing The Hong Kong Polytechnic University Kowloon Hong Kong 999077 P. R. China
3. Department of Civil & Environmental Engineering The Hong Kong Polytechnic University Kowloon Hong Kong 999077 P. R. China