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Information × Registration Number 0211U009843, 0109U001432 , R & D reports Title Physical processes and properties of new developed amorphous and nanocrystalline bioactive materials popup.stage_title Head Zyman Zoltan Zoltanovich, Registration Date 30-12-2011 Organization Kharkov National University named after V.N. Karazin popup.description2 Object of research - nanodispersive calcium-phosphate materials based on hydroxyapatite, synthesized by the original procedure. The purpose of work - examination of composition, structure and properties of amorphous calcium phosphate formed at an initial stage of hydroxyapatite precipitation. Study of hydroxyapatite crystallization from amorphous calcium phosphate, and the nanocrystal growth. Production of new calcium-phosphate materials with the given phase composition and the functional properties. Researches of features of structure and impurities composition of nanocrystalline hydroxyapatite synthesized by microwave irradiation. Study of the relationship between the mechanical properties of the sintered hydroxyapatite ceramics and the synthesis parameters of nanostructured materials. Methods of research - x-ray structure analysis, electron microscopy, mass-spectrometry of gases, IR-spectroscopy, mechanical properties (linear and volume shrinkage, density, Vickers microhardness, compressive strength). It is shown, that particles of amorphous calcium phosphate which are formed at an early stage of the hydrohyapatite precipitation are the amorphous-crystalline complex consisting from nanoclusters and unit cells of hydroxyapatite. The transformation of amorphous calcium phosphate to hydroxyapatite and the mechanism of hydroxyapatite nanocrystal growth by integrating of unit cells in particular crystallographic directions are offered. The received data on features of composition, structure and properties of amorphous calcium phosphate particles have allowed creating new calcium-phosphate materials with a required phase composition. New calcium-phosphate materials synthesized by microwave irradiation. Their structure, phase and impurity composition is studied. Dependences of functional properties of sintered ceramics on the basis of nanostructured materials were investigated. Product Description popup.authors Зиман З. Кійко С. Пяничук О. Рохмістров Д. Сіренко А. Суров Ю. Ткаченко М. popup.nrat_date 2020-04-02 Close