Paramagnetic Centres in Oxidised Coal

• Authors: L. Najder-Kozdrowska , R. Samoilova , R. Kappl , J. Hüttermann , A. Więckowski
• Languages of publication: EN

Abstracts

EN

This paper comprises the results obtained by continuous wave (cw)/pulse electron paramagnetic resonance spectroscopy for oxidised coals. The values of EPR linewidths are different for samples of coal treated by different chemical agents. The asymmetric EPR line shape indicates to complex composition of paramagnetic centres in coal. In coal oxidised by HNO_3 big changes of linewidth with temperature were observed. For all samples the spin-lattice relaxation time T_1 was determined by pulse EPR method. The correlation between used chemical agents and the value of T_1 was established.

Keywords

EN

33.35.+r; 61.66.Hq; 76.30.Rn; 89.30.ag

Discipline

• 76.30.Rn: Free radicals
• 61.66.Hq: Organic compounds
• 89.30.ag: Coal
• 33.35.+r: Electron resonance and relaxation(see also 76.30.-v Electron paramagnetic resonance and relaxation in condensed matter)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2010
• Volume: 118
• Issue: 3
• Pages: 475-479

Dates

published

2010-09

Contributors

author

L. Najder-Kozdrowska

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

author

R. Samoilova

• Institute of Chemical Kinetics and Combustion, Russian Academy of Sciences, Novosibirsk 630090, Russia

author

R. Kappl

• Institute of Biophysics, Faculty of Medicine, University of Saarland, 66421 Homburg (Saar), Germany

author

J. Hüttermann

• Institute of Biophysics, Faculty of Medicine, University of Saarland, 66421 Homburg (Saar), Germany

author

A. Więckowski

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

References

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Identifiers

DOI

10.12693/APhysPolA.118.475