Determination of the fraction of paramagnetic centers not-fulfilling the Curie law in coal macerals by the two-temperature EPR measurement method

• Autorzy: Słowik G. P. , Więckowski A. B.

Identyfikatory

DOI

10.1515/nuka-2015-0069

• Konferencja: III Electron Magnetic Resonance Forum EMR-PL (3 ; 23-25.05.2014 ; Kraków, Poland)
• Języki publikacji: EN

Abstrakty

EN

Two-temperature electron paramagnetic resonance (EPR) measurements, applied to determine the relative contributions of paramagnetic centers – fulfilling and not-fulfilling the Curie law, were carried out. The measurements were made on the macerals – exinite and vitrinite, separated from clarain of the Polish medium- -rank coal (85.6 wt% C). The two-temperature EPR measurements, presented in this work, were performed respectively, at temperatures: T1 = 293 K and T2 = 173 K for exinite, and T1 = 293 K and T2 = 153 K for vitrinite. The relative contributions X of spins not-fulfilling the Curie law present in the studied macerals were calculated. A comparison of different methods of calculating the relative contributions of paramagnetic centers – fulfilling and not-fulfilling the Curie law, present in exinite and vitrinite studied by EPR was made.

Słowa kluczowe

EN

electron paramagnetic resonance (EPR); macerals; two-temperature EPR measurement

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2015
• Tom: Vol. 60, No. 3, part 1
• Strony: 389--393
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Słowik G. P.

• Institute of Physics, Faculty of Physics and Astronomy, University of Zielona Góra, 4a Szafrana Str., 65-516 Zielona Góra, Poland

autor

Więckowski A. B.

• Institute of Physics, Faculty of Physics and Astronomy, University of Zielona Góra, 4a Szafrana Str., 65-516 Zielona Góra, Poland
• Institute of Molecular Physics of the Polish Academy of Sciences, 17 Smoluchowskiego Str., 60-179 Poznań, Poland

Bibliografia

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