1. Institute of Physics of Soft Fibrous Materials, Dong Hua University, Shanghai, 200051, China, , Division of Textiles, Biological & Agricultural Engineering, UC Davis, CA 95616, U.S.A
2. Also at College of Science, Dong Hua University, Shanghai, 200051, China
3. College of Textiles, Dong Hua University, Shanghai, 200051, China