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Information × Registration Number 0305U003610, 0103U003373 , R & D reports Title Conjugated heterovalent substitutions of trivalent elements for alkaliearths in compounds having an apatite structure. popup.stage_title Ізоморфне заміщення кальцію на рідкісноземельні елеме-нти в структурі гідроксиапатиту кальцію. Робота над базою даних ізоморфних заміщень. Head Getman E., Registration Date 19-05-2005 Organization Donetsk National University popup.description2 Isomorphous substitution of rare earths (Ln = Ce, Pr, Nd, Gd, Dy, Ho, Tm, Yb) for calcium in Ca5-xLnx(PO4)3(OH)1-xOx has been inves-tigated by X-ray powder diffraction and IR-spectroscopy. It was es-tablished, that the limits of substitution vary from х ? 1,0 (Nd, Pr) to х = 0,7 (Gd, Dy) and х ? 0,4 (Ho, Tm, Yb). Increase of the Ln content in hydroxyapatite leads to decrease in cell parameters of a solid solu-tion of the apatites modified by Ln from Gd up to Yb, and to increase in these while Nd and Pr substitute for Са. Also it was shown, that the parallel reaction of OH- removing from hydroxyapatite and formation of vacancies take place in solid solutions under consideration. Re-finement of crystal structure of the Ca5-xLnx(PO4)3(OH)1-xOx solid solutions by Rietveld method was carried out. Product Description popup.authors popup.nrat_date 2020-04-02 Close