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Information × Registration Number 0215U008297, 0113U003172 , R & D reports Title Structural and phase transformations in the hetero-, nan0- and micro-dispersive systems popup.stage_title Head Kramar Valeriy Maksymovych, Registration Date 25-12-2015 Organization Yuri Fedkovych Chernivtsi National University popup.description2 As a result, of the research we constructed ostwald ripening theory of nanoparticles strengthening phase in metal alloys, in a simultaneous action of two growth mechanisms controlled by dislocation diffusion and the rate of formation chemical bonds; establish accordance of existing theories ostwald ripening new experimental facts, that accrued at the present time, due to the development of nanotechnology. In the frame of the reseach we carry out an attempt to spread LSW modified theory, initially developed for 3D- solid-state systems, on liquid media. The main focus is on the problem of stability of the dispersed phase in the process of ostwald ripening, which determines the stability of the structure as a whole. The regularities of the growth particles of nanodispersed phases during ostwald ripening in volume 3D-systems (alloys, nanocomposites, liquid solutions) and surface 2D-systems (semiconductor heterostructures, thin films, two-dimensional matrix hole with perfect periodicity) in terms of the proposed mechanism of growth. The interaction of electrons, holes and excitons with optical phonons in planar semiconductor nanofilms with different strength of the electron-phonon coupling was studied. Concrete calculations were made on the example of layered 2H-PbI2 semiconductor nanofilms, contained in the dielectric medium - glass or E-MAA polymer, GaAs in matrix of variable composition and ?-HgS in the matrix ?-CdS considering the effects of spatial constraints, selfpolarization and interaction with optical phonons. It made it possible to settle the spectral dependence of exciton absorption coefficient in mentioned nanofilms and explore the transformation of the absorption band, when changing their thickness, temperature, and, in the case of AlxGa1-xAs/GaAs/AlxGa1-xAs - composition of barrier medium. The obtained results formed the basis of research possibilities of realization in mentioned structures the phenomenon of internal optical bi-stability and influence of external factors (polarization and angle of incidence of exciting waves, temperature, magnetic field strength, film thickness) on the position and size of the hysteresis loop depending on the intensity of illumination. Product Description popup.authors Іванський Богдан Васильович Венгренович Роман Дмитрович Деревянчук Олександр Володимирович Кондрюк Денис Васильович Крамар Валерій Максимович Кройтор Ольга Петрівна Москалюк Анатолій Валерійович Панько Ігор Ігорович Пуганцева Олена Валеріївна Стасик Мирослав Остапович Ткач Оксана Олександрівна popup.nrat_date 2020-04-02 Close