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Information × Registration Number 0201U003642, 0100U003276 , R & D reports Title Influence of electrons and phonons scattering processes on low temperatures transport properties of complicated solid-state systems popup.stage_title Head Merisov B.O.; Khadzhaj G.Ya., Registration Date 03-04-2001 Organization Kharkov National University named after V.N. Karazin popup.description2 The objects of research are the metal-hydrogen system TaHx; quasi-one-dimensional quantum magnetic system Sr14-xCaxCu24O41; alpha-Ti and martensite steel 03Х9К14Н6М3Д. The purpose of operation is searching quantum effects in the heat and charge transport and in scattering carriers in complicated solid-state systems at low temperatures; study of influence of the monoaxial loading on thermal linear expansion of alpha-Ti. The methods of researches: the method of monoaxial stationary heat flux for measurement of a thermal conduction; the four-probe method of measurement of a resistance and the dilatometric method of measurement of linear expansion. It is established, that the hydrogen caused additional electrical resistance of the ТаНх (х = 0.0016, 0.0071, 0.04) samples in the interval 5-100 K has the nonmonotonic temperature dependence, passed through a diffusion maxima in area 50K. Such behaviour of additional resistance we connect with inelastic scattering of electrons on a distorted phonon spectrum , with the admixtured ions, and also with interferential scattering. In the field of room temperatures the electrical resistance of a two-phase system TaH(D)x exceeds the greatest possible value obtained from resistances of separate phases and their volume fractions. This overflow we connect with the significant contribution of interphase boundaries to system resistance. The simple formula for approximating conductivity (or resistance) two-phase systems is offered which is suitable in a case, when the resistances of phases are close enough. It is shown, that in high-quality samples of quasi-crystals of the Y-Mg-Zn system predominates the phonon heat transport with scattering of phonons on phonons and flat imperfections. It is detected the Muiji correlation in the martensite steel 03Х9К14Н6М3Д. It is established, that the elastic monoaxial loading up to 60 kPa in the basis plane of alpha-Ti result in the perturbation of anharmonic parameters on 32% greater, than in a perpendicular direction. Product Description popup.authors popup.nrat_date 2020-04-02 Close