Compositional variations in apatites with respect to preferential ionic extraction.

F J Cuisinier; R W Glaisher; J C Voegel; J L Hutchison; E F Brès; R M Frank

doi:10.1016/0304-3991(91)90122-m

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Compositional variations in apatites with respect to preferential ionic extraction.

F J Cuisinier·R W Glaisher·J C Voegel·J L Hutchison·E F Brès·R M Frank

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Abstract

Detection of ionic losses from the apatitic structure (Ca10(PO4)6(OH)2) by high-resolution electron microscopy was investigated theoretically. Linear image analysis showed the need for an objective aperture of at least 3.7 nm-1 to visualize four different coordinates (CaII, OH-, P and mid-point between CaII-P bond). High-resolution image analysis and plotting of OH- column intensity against specimen thickness showed an inverse proportionality between composition and OH- image intensities for very thin specimens (less than 2 nm). Image intensity variation would be detectable experimentally, but the preparation of such thin specimens by ultramicrotomy is impossible.

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F J Cuisinier, R W Glaisher, J C Voegel, J L Hutchison, E F Brès, R M Frank. 1991. Compositional variations in apatites with respect to preferential ionic extraction.. https://doi.org/10.1016/0304-3991(91)90122-m

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