| 摘要 |
<p>In the present invention, there is disclosed a process for preparing apatite and apatite composite with photocatalytically active titanium dioxide by precipitating from aqueous solutions of a mixture of soluble calcium salt, ammonium hydrogen phosphate and titanyl sulfate wherein the process is characterized in that the reaction mixture of the calcium salt and the ammonium hydrogen phosphate in a molar ratio of 5:3, and optionally with addition of titanyl sulfate, is subjected to hydrolysis by urea to pH value higher than 8. Apatite composite with photocatalytically active titanium dioxide can be prepared in such a manner that apatite is coated with a thin layer of anatase by reacting TiOSOi4 with urea at a temperature ranging from 80 to 100 degC and at pH higher than 8. Apatite and anatase composite, in which spherical nanoparticles are coated with a thin layer of apatite can be prepared in such a way that reaction mixture of a calcium salt and ammonium hydrogen phosphate, being present in molar ratio of 5:3, is hydrolyzed by urea to pH value higher than 8.</p> |
