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Information × Registration Number 0223U004734, 0123U102865 , R & D reports Title Quantum tunneling of oscillatory excitations in thermal conductivity of crystalline and amorphous materials and composites popup.stage_title Head Kryvchikov Oleksandr I., Доктор фізико-математичних наук Registration Date 30-11-2023 Organization B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine popup.description2 During the 2023 Project stage, temperature dependencies of thermal conductivity were established for amorphous glycerin, the polymer material, and a graphene composite. The obtained results are crucial for understanding the nature of the temperature dependence of thermal conductivity, particularly the manifestation of universal features described within the framework of the empirical universal approach to describing the conductivity of crystalline, amorphous, and nanostructured materials. A comparative analysis of literature data on diffusive contributions to the conductivity of various crystalline and amorphous materials was performed, taking into account the functional dependence of the contribution of quantum tunneling to conductivity. We calculated activation energies using experimental results of the temperature dependences of isobaric and isochoric thermal conductivity of molecular amorphous and crystalline materials. The obtained results are important for further study of thermal conductivity and identification of universal features and verification of the empirical universal approach to the description of thermal conductivity of crystalline, amorphous and nanostructured solids. The functional dependencies of the contribution of quantum tunneling to the thermal conductivity are obtained and the activation energies are calculated by using comparative analysis of the diffusion contributions to the thermal conductivity of various crystalline and amorphous materials (Task 1 SPI 6 in the applications). The obtained information on the temperature dependence of thermal conductivity of the studied series of crystalline and amorphous materials and the influence of quantum tunneling contribution to thermal conductivity is universal and important for detecting the influence of structure features and predicting thermophysical features of nanomaterials and composites.   Product Description popup.authors popup.nrat_date 2023-11-30 Close