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Tonegawa, Toru*; Ikoma, Toshiyuki*; Suetsugu, Yasushi*; Igawa, Naoki; Matsushita, Yoshitaka*; Yoshioka, Tomohiko*; Hanagata, Nobutaka*; Tanaka, Junzo*
Materials Science & Engineering B, 173(1-3), p.171 - 175, 2010/10
Times Cited Count:11 Percentile:46(Materials Science, Multidisciplinary)The thermal expansion and crystal structure of A-type carbonate apatite with the monoclinic symmetry was investigated using the neutron powder diffraction at room temperature, 200, 300, 400 and 500C. The -axis and -axis lattice parameters were 0.9568 and 0.6868 nm at room temperature, and those were linearly increased with the increase of temperature. It was found that the linear thermal expansion coefficient of -axis was 1.3110/C and -axis 8.0710/C.
Tonegawa, Toru*; Ikoma, Toshiyuki*; Suetsugu, Yasushi*; Igawa, Naoki; Matsushita, Yoshitaka*; Yoshioka, Tomohiko*; Hanagata, Nobutaka*; Tanaka, Junzo*
Proceedings of 22nd International Symposium on Ceramics in Medicine (BIOCERAMICS-22), p.93 - 96, 2009/12
Hydroxyapatite is the main inorganic component of bone and tooth minerals, in which CO ions partially substitute for OH and/or PO ions. In this study, high purity type A carbonate apatite, Ca(PO)(CO) powder completely substituted by carbonate ions were synthesized by a treatment of low crystalline hydroxyapatite powder, Ca(PO)(OH)) in a dry CO flow at 1000 C. The crystal structure of the sample was the monoclinic symmetry with space group of and the lattice parameters, = 0.9566 (1), = 1.9063 (2), = 0.6867 (1) nm and =119.84 (1), which was refined by a Rietveld method with neutron diffraction data.