1. College of Material Sciences and Engineering; State Key Laboratory of Chemical Resource Engineering; Beijing University of Chemical Technology; Beijing 100029 PR China
2. Beijing Laboratory of Biomedical Materials; Beijing University of Chemical Technology; Beijing 100029 PR China
3. China Lucky Group Corporation; Baoding 071054 PR China
4. Department of Craniofacial Biology; School of Dental Medicine; University of Colorado Anschutz Medical Campus; Aurora Colorado 80045 USA