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Information × Registration Number 0223U001795, 0122U001972 , R & D reports Title Phase transitions and kinetic properties of molecular systems with spatial nanohomogeneities relevant to environmental safety and medicine popup.stage_title Head Lazarenko Maksym M., Доктор фізико-математичних наук Registration Date 03-02-2023 Organization Taras Shevchenko National University of Kyiv popup.description2 Research object – Phase transitions, relaxation processes and transport phenomena in systems with nanoscale spatial inhomogeneities. The purpose of the work is to establish the regularities of the influence of spatial restrictions and interaction at the nanoscale inclusion–macroenvironment boundary on the parameters of phase transitions, relaxation processes, and the kinetics of heat and mass transfer in spatially heterogeneous systems as a whole and to create physical models of the observed phenomena, taking into account such influence. Research methods are thermophysical, dielectric, spectroscopic, rheological, structural, theoretical and analytical. It is shown that 1-octadecene both in the porous silicon matrix and in the bulk crystallizes with an orthorhombic subcell, while undecenoic acid in the porous silicon matrix and in the bulk crystallizes with different subcells. Phase transitions and relaxation processes in the nanostructured system porous silicon – 1-octadecene and undecenoic acid are shifted toward low temperatures and are associated with the movement of topological solitons along aliphatic chains. The effect of lowering transition temperatures and changing the structure of substances in a nanostructured state can be used to improve the bioavailability of drugs. It has been established that water molecules can be embedded in the crystalline regions of cellulosic materials in an order of magnitude comparable to the number of water molecules embedded in amorphous regions. It is shown that the relaxation process in nanocellulose-water systems is related to the surface layers of nanocellulose particles, which are surrounded by a hydrate shell, and the mechanism of dielectric relaxation is related to the reorientation of the surface methylol groups of the cellulose molecule by changing their conformations from tg to tt. Product Description popup.authors Alieksieiev Oleksandr M. Andrusenko Dmytro A. Brytan Andry V. Vergun Liena Yu. Hnatyuk Kateryna I. Kovalchuk Valeriy I. Ogorodnik Kateryna O. popup.nrat_date 2023-02-03 Close