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Information × Registration Number 0215U001368, 0112U005918 , R & D reports Title Development of nano- and microdisperse functional materials with magnetic parameters of macroscopical analogs popup.stage_title Head Olkhovyk Larysa P., Registration Date 16-02-2015 Organization Kharkov National University named after V.N. Karazin popup.description2 Object of study - high- and low-anisotropic ferrites with spinel-type crystal structure in the form of nano-andmicrodispersepowders. The purpose of study - development of new physical and technological principles and a process for the obtaining of fine ferrite systems with chemical composition, particle size and magnetic properties required for use in the biomedical field. The purpose of the study - the approach of the magnetic parameters of nano- and microdisperseferrite materials to the level of macroscopic counterpart, which would not have restrictions on the dispersion of particles and the chemical composition of the compound. Using the methods of chemical condensation of aqueous solutions of salts and pyrolysis method were obtained micro- and nanoparticle systems of high-anisotropiccobalt ferrite CoFe2O4 particles and nanoparticle systems of low-anisotropicof zinc-substituted ZnxFe3-xO4 magnetite and copper ferrite CuFe2O4. X-ray analysis showed single-phase of the samples and their compliance with the crystal structure of spinel-type structure. Magnetization of microcrystalline powder CoFe2O4 only by 10% lower than the magnetization of macroanalogue, for nanopowder this difference is about 30% in connection with significant volume part (~ 55%) of structurally defective surface layer. At the example ofZnxFe3-xO4 first showed that for ultralow (d <10 nm) nanocrystalsdimensional factor have primary role in forming of magnetization, while the method of purposeful change (increase) by diamagnetic substitution is not realized. System of ZnxFe3-xO4(x ? 0.5) samples revealed expected superparamagneyic properties in the therapeutic temperature range. It was shown that result of surface modification of ferrite particles by treatment with aggressive media (HCl, NaOH) is in increase of magnetization of powders, which on ferrite CuFe2O4only12% is below the value for macroscopic counterpartsbut in the case of ferrite BaFe12O19 - is below 10%. By results of the studywas received a patent for invention. Product Description popup.authors Борисова Н. Голубенко З. Коваль А. Ольховик Л. Сизова З. Ткаченко М. popup.nrat_date 2020-04-02 Close