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Information × Registration Number 0223U005167, 0120U103480 , R & D reports Title Experimental research and computer modeling of physicochemical processes in lava-like fuel-containing materials of the NSC-SO complex popup.stage_title Head Habielkov Serhii V., Доктор фізико-математичних наук Registration Date 16-12-2023 Organization Institute for Safety Problems of Nuclear Power Plants of the National Academy of Sciences of Ukraine popup.description2 For the first time, the presence of the mineral Rameauite in LFCM black ceramics was established. The presence of oxide UO2,338 (U4O9) and chornobylite Zr1-xUxSiO4 was confirmed. It was established that during the stay at the "Shelter" facility after the accident, the uranium oxide UО2 of the nuclear fuel oxidized to UO2,338 (U4O9). The main part of the uranium oxide, which was in the inclusions in the LFCM, during its stay in the "Shelter" facility, turned into the mineral Rameauite. Also found are crystalline phases that do not contain U: magnesium oxide MgO, Kotoite, a calcium magnesium silicate CaMgSiO4, magnesium aluminate (spinel) MgAl2O4, and magnesium silicates MgSiO3 and Mg2SiO4. For the first time, the phases of black ceramics are divided into three groups according to their "origin": before, during, and after the accident. Several physical and chemical processes have taken place and are taking place in black LFCM ceramics. The passage of the processes of hydration of uranium oxide and crystallization of the glass phase was confirmed. The process of hydration of the glass phase with the formation of hydroxides that do not contain uranium was discovered for the first time. The model of the evolution of the LFCM structure was modernized thanks to data from black ceramics. Added another relevant stage. The prediction also indicates that the combination of oxidation and hydration processes of uranium oxide almost stopped in the black ceramic and significantly slowed down in the brown one. Crystallization of the glass phase will be the main process that will determine the behavior of LFCM in the future. The updated model of the evolution of the microstructure of LFCM will allow for improved quality forecasts of the state and behavior of these materials in the near and distant future. Product Description popup.authors Zhyganiuk Igor Viktorovych Skorbun Anatolii D. popup.nrat_date 2023-12-16 Close