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Magnesium (Mg) and its alloy as promising biodegradable orthopaedic implants have gained immense attention by virtue of their superior biocompatibility and mechanical compatibility. In order to increase the long-term corrosion resistance of Mg and its alloys in clinical application, in this work, a series of strontium-substituted hydroxyapatite (SrHA) coatings were constructed on Mg alloy via hydrothermal route. These SrHA coatings possessed bilayer structure with flower-like clusters as the surface layer and flat surface as the bottom layer. Coating III with Sr/Ca molar ratio of 0.07 exhibited crack-free bottom layer and good interfacial adhesion, and its electrochemical corrosion resistance was higher than the counterparts. Moreover, this coating with high dissolution and rough surface rapidly induced SrHA mineralized layer formation, which gradually grew dense and thick, providing favorable long-term protection for Mg alloy. After immersion in simulated body fluid for 29 days, the average degradation rate of Mg alloy decreased to 0.17 mg/day•cm 2. The present work demonstrated that this SrHA coating was a potential protective coating for Mg and Mg alloy implants.

Theu niquer eactivity ands ynthetic applications of oxime acetate derivatives with N, Oa nd S substituents at the a-position are disclosed for the first time,w hich leads to 2-substitutedf ulleropyrrolidines and mono-andd isubstituted 1-fulleropyrrolines via copper-catalyzedr edox-neutral N-heteroannulation reactions with C 60 .T his transformation is operationally simplea nd has ab road substrate scope and good functional group tolerance.T heoretical calculations at the level of B3LYP/6-31G(d) were performed to elucidate the chemoselectivity of the reaction.

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