Fluorine in Shark Teeth: Its Direct Atomic-Resolution Imaging and Strengthening Function Chen, Chunlin ; Wang, Zhongchang ; Saito, Mitsuhiro ; Tohei, Tetsuya ; Takano, Yoshiro ; Ikuhara, Yuichi Abstract Publication: Angewandte Chemie Pub Date: February 2014 DOI: 10.1002/ange.201307689 Bibcode: 2014AngCh.126.1569C