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2005 | 108 | 2 | 403-407
Article title

Multi-Component EPR Spectra of Coals with Different Carbon Content

Content
Title variants
Languages of publication
EN
Abstracts
EN
EPR spectra of lignite"Mequinenza" (Spain) (62.3 wt% C) and Polish orthocoking coal (87.8 wt% C) were compared. The spectra were superpositions of broad Gaussian, broad Lorentzian 1, and narrow Lorentzian 3 lines. Concentration of paramagnetic centers - mainly delocalizedπ electrons - responsible for narrow Lorentzian 3 lines increases with increase in carbon content in coal. Coal units with slow and fast spin-lattice relaxation processes exist in the two studied samples. Slow spin-lattice interactions occur in simple aromatic coal units with broad Gaussian and Lorentzian 1 lines. Fast spin-lattice relaxation processes are characteristic of large aromatic units with narrow Lorentzian 3 lines.
Keywords
EN
Publisher

Year
Volume
108
Issue
2
Pages
403-407
Physical description
Dates
published
2005-08
received
2005-04-24
Contributors
author
  • Institute of Coal Chemistry, Polish Academy of Sciences, Sowińskiego 5, 44-121 Gliwice, Poland
  • Division of Magnetic Resonance Spectroscopy, Institute of Physics, Faculty of Physics & Astronomy, University of Zielona Góra, Szafrana 4a, 65-516 Zielona Góra, Poland
author
  • Laboratory of Coal Chemistry and Technology, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland
author
  • Laboratory of Coal Chemistry and Technology, Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland
References
  • 1. B. Pilawa, A.B. Wieckowski, R. Pietrzak, H. Wachowska, Mol. Phys. Rep., 34, 127, 2001
  • 2. B. Pilawa, A.B. Wieckowski, R. Pietrzak, H. Wachowska, Fuel, 81, 1925, 2002
  • 3. W. Radmacher, P. Mohrhauer, Brennstoff-Chemie, 37, 353, 1956
  • 4. R. Pietrzak, H. Wachowska, Fuel, 82, 705, 2003
  • 5. B. Pilawa, A.B. Wieckowski, B. Trzebicka, Mol. Phys. Rep., 4, 245, 1994
  • 6. B. Pilawa, A.B. Wieckowski, B. Trzebicka, Radiat. Phys. Chem., 45, 899, 1995
  • 7. B. Pilawa, B. Trzebicka, A.B. Wieckowski, Fuel, 70, 1109, 1991
Document Type
Publication order reference
Identifiers
YADDA identifier
bwmeta1.element.bwnjournal-article-appv108n223kz
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