Abstract We study the initial process of the rapid Ca-P crystallization in SBF by ex situ and in situ observation. To reduce the crystallization rate, calcite are present in the system. Ex situ measurements revealed that amorphous calcium phosphate (ACP) immediately precipitated on SiO2 substrate. The inside of transformed to the calcium hydrogen phosphate. In situ observation indicated that the formation of the DCPD started at day 7 and the DCPD region gradually increased inside ACP particles. Our results showed a solid-solid phase transition from ACP to DCPD. We propose the new pathway of Ca-P crystallization.

中文翻译：

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模拟体液中无定形磷酸钙向二水磷酸氢钙的相变

摘要 我们通过非原位和原位观察研究了SBF 中Ca-P 快速结晶的初始过程。为了降低结晶速率，系统中存在方解石。非原位测量显示无定形磷酸钙 (ACP) 立即沉淀在 SiO2 基材上。内部转化为磷酸氢钙。原位观察表明，DCPD 的形成开始于第 7 天，并且 DCPD 区域在 ACP 颗粒内部逐渐增加。我们的结果显示了从 ACP 到 DCPD 的固-固相转变。我们提出了钙磷结晶的新途径。