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Information × Registration Number 0220U101341, 0119U102391 , R & D reports Title Phonon interaction in nanomaterials, molecular crystals and quantum liquids popup.stage_title Head Barabashko Maksym S., Кандидат фізико-математичних наук Registration Date 10-02-2020 Organization B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine popup.description2  Experimental studies of the oscillatory characteristics of quartz tuning fork at low temperatures carried out. It was shown the results of measurements in vacuum at 1,5 K practically coincide with the data obtained at 0,7 K when a tuning fork covered with helium film. The e xperimental results were comparised with previously obtained data on the nonlinear dependence established in the experiments with the same tuning fork immersed in superfluid helium under conditions of turbulent fluid flow. They were analyzed with the nonlinear Duffing equation, which allowed to get the temperature dependence of the tuning fork nonlinearity coefficient and the coefficient of mutual friction caused by the turbulent flow of the superfluid fluid. The of isochoric thermal conductivity of the plastic phase halogenated ethane - R-152a were investigated for three samples with different density. It was found the thermal conductivity growth with the temperature; it can be associated with two possible mechanisms: 1) with inhibition of the rotational motion of molecules and decreasing of phonon scattering; or 2) with the interaction of intramolecular and acoustic modes. Product Description popup.authors popup.nrat_date 2020-04-02 Close