The growth of nonstoichiometric apatite from aqueous solution at 37°C. II. effects of pH upon the precipitated phase.

摘要: Abstract Apatite growth was studied at 37°C over a pH range 6.0 to 9.0 using the constant composition method. Observed changes in total calcium and phosphate molar concentrations of supersaturated solution during experiments, with effective titrant calcium/phosphate ratios 1.67 or 1.40, were interpreted terms formation nonstoichiometric apatites having formula Ca 10−u ( HPO 4 ) 6−u OH 2−u The atomic ratio grown phase, verified by X-ray diffraction studies, found vary from 1.49 1.65 as working changed 9.0. At 6.0, it estimated that protonation surface would change only 0.02. It is therefore concluded nonstoichiometry associated material. There no indication existence other types vacancies. these seeded experiments compared those produced coversion an amorphous phase.