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Information × Registration Number 0207U000698, 0104U008137 , R & D reports Title Electronic properties of low-dimentional structures and their systems (theory, experiment, technology) popup.stage_title Head Nishchenko Mikhail, Registration Date 31-01-2007 Organization Institute for metal physics NAS Ukkraine popup.description2 Objects of studies: nanotubes, teflon, their composites, bicrystalline YBCO films, magnetic nanoparticles. The goal: the nanotubes effect on polymers defect structure, absorption of UHF radiation, and teflon polarization under the laser-generated shock-waves. Development of the theory for surface covalent bonds of the nanostructures, tecnologies of fabrication and investigation of maltilayered Josephson nanostructures, bicrystalline YBCO films. Methods of investigation: positron spectroscopy, electrophysical, magnetic, quantum-statistical calculations. The nanotubes in polymer matrix are shown to be the sites of positron trapping and their embedding leads to disappearance of small nanovoids (0.4 nm in size) and appearance of larger ones (~ 1 nm). It results in the 2 orders of magnitude increase of UHF-radiation damping and 1 order - of teflon polarization. First-order phase transitions of metallic particles to semiconducting ones upon the decrease of their size were calculated. Theory of the second-order transitions in isolated points is proposed. Nonlinear properties of the bicrystal YBCO microstrip-line UHF resonator were investigated. Product Description popup.authors popup.nrat_date 2020-04-02 Close