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Information × Registration Number 0212U005042, 0111U004826 , R & D reports Title Setting aggregate spectroscopic charasteristics of coal typical methane rich coal seam. popup.stage_title Head Valakh Mykhailo Yakovych, Доктор фізико-математичних наук Registration Date 20-02-2012 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 At this stage of the project carried out further research to improve the methods of natural properties of coal by electron microscopy, Raman and EPR spectroscopy, used to obtain new and important results. Using these techniques, combined with theoretical calculations carried out a comprehensive systematic study of local structure and the paramagnetic properties of a set of coal samples from different deposits, the Donets Basin, which are characterized by a low degree of metamorphism. It is proved that we made at the previous stage of the study concluded that there is a correlation between the type of coal, the characteristics of its local structure in Raman data, and paramagnetic properties, valid for this more restricted class of coal. Investigation of a given set of samples also showed that for almost all types of coal are characterized by signals from the photoluminescence (PL), the intensity of which varies by 1-2 orders of magnitude depending on the type of specimen and site-specific localization of the exciting laser radiation. Established decrease in FL signal intensity with time, which is associated with the processes of oxidation of coal samples and a decrease in hydrogen content, which is considered in the literature, is responsible for the PL signals in the natural coal. The study of the paramagnetic properties of the samples from the same field, taken before and after uncontrolled gas dynamic phenomena (GDP) (methane outburst), show distinct EPR characteristics of these samples, the cause of which is associated with a change in gas composition of the samples and the growth of voids in the process of ejection. Theoretical calculations show that the energy of interatomic bonds of atoms and molecules of hydrogen and carbon wall of the open pores on the order of magnitude smaller than the binding energy of the molecule, in the closed pores of the hydrogen molecule is unstable. A comparison of the experimental data and theoretical calculations determined the rate of diffusion of hydrogen and oxygen in coal and natural nanoporous carbon. Product Description popup.authors Кончиць Андрій Андрійович Шаніна Белла Дмитрівна Юхимчук Володимир Олександрович Янчук Ігор Богданович Янчук Ігор Богданович popup.nrat_date 2020-04-02 Close