<abstract xmlns="http://www.w3.org/1999/xhtml">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: <italic>T</italic>1 = 293 K and <italic>T</italic>2 = 173 K for exinite, and <italic>T</italic>1 = 293 K and <italic>T</italic>2 = 153 K for vitrinite. The relative contributions <italic>X</italic> 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.</abstract>

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.

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

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

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

Nukleonika

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Two-temperature electron paramagnetic resonance (EPR) measurements, applied to determine the relative contributions of paramagnetic centers – fulfilling and...

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

Publié en ligne: 06 août 2015

Pages: 389 - 393

Reçu: 01 oct. 2014

Accepté: 30 janv. 2015

DOI: https://doi.org/10.1515/nuka-2015-0069

Mots clés
electron paramagnetic resonance (EPR), macerals, two-temperature EPR measurement

© Grzegorz P. Słowik et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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

Publié en ligne: 06 août 2015

Pages: 389 - 393

Reçu: 01 oct. 2014

Accepté: 30 janv. 2015

DOI: https://doi.org/10.1515/nuka-2015-0069

Mots cléselectron paramagnetic resonance (EPR), macerals, two-temperature EPR measurement

© Grzegorz P. Słowik et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Mots clés
electron paramagnetic resonance (EPR), macerals, two-temperature EPR measurement