1. National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, China
2. College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China
3. Leather and Shoe Research Association of New Zealand, P.O. Box 8094, Palmerston North 4472, New Zealand
4. National Synchrotron Radiation Research Centre (NSRRC), Hsinchu 30076 Taiwan, China