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Information × Registration Number 0205U000076, 0104U007003 , R & D reports Title The study of nanodimension subsystems in biogenic and synthetic materials popup.stage_title Head Lytovchenko Anatoly Stepanovich, Registration Date 12-01-2005 Organization nstitute of Geochemistry, Mineralogy and Ore Formation popup.description2 The research object - the teeth enamel and synthetic analogues of biominerals. The main purpose of the present work was the further specification of the structure principles of the internal structure of teeth enamel and the investigation of the characteristics of teeth enamel and its synthetic analogues by the spectroscopy methods. The research methods - the electron paramagnetic resonance (EPR), the proton magnetic resonance (PMR), IR-spectroscopy, the luminescence, the X-ray analysis. The researches of the main organic and mineral subsystems of a teeth enamel and a dentine, and synthetic analogues of biominerals also have been fulfilled by the complex of the spectroscopy methods It is established, that there are protons of nonocapillary water, slow and mobile protons of organic substance, protons of hydroxyl groups, included in a bioapatite structure, and protons of crystallohydrated water in the enamel structure. It has been determined, in what enamel subsystem the appropriate protons are located,and the temperature intervals, in which these protons have been withdrawn from the structure, have been found. It is shown, that the water layers play the role of the barrier layer, which adjusts masstransfer processes between an organic and a mineral substances in biominerals. The biomineral mineralization occurs, on the one hand, via to replacement of weakly bounded water by carbonate-apatite, and, on the other hand, the carbonate substance inhibits the phosphate growth and provides the preservation of the organic matrix during mineralization. It is shown, that on the basis of the obtained data it is possible to investigate the mechanisms of processes, occurring in different subsystems of an enamel under influence of the external factors It is established, that isomorphic replacements by the scheme 2Са2+II > Ме+(К, Li)II Ме3+(Lа)II result in formation, except for the ОН--О--ОН- (3СаII) centre, new O-- centres, with ions of alkaline metals and lanthanum in the nearest environment: VOH-О--ОН- (Ме+II 2Са2+II),О2--О--ОН- (2Ca2+II La3+II), О2--О--О2- (2СаII LaII). The obtained data on parameters О-- centres in replaced patites are supposed to be used for the estimation of an isomorphic replacement degree in different structural positions of apatite. Product Description popup.authors popup.nrat_date 2020-04-02 Close