Control of Ca/P Molar Ratio of Plate-shaped Hydroxyapatite Powders With an </i>a(b)</i>-axis Orientation and Their Thermal Stability : Figure 7

Figure 7: FT-IR spectra of the hydrothermal-treated powders for 2.5 h in a solution of 1.0 mol•dm^-3 CaCl₂: hydrothermal temperature (a) 100, (b) 120, (c) 140, (d) 160 and (e) 180˚C.