Temperature and frequency-dependent proton relaxation measurements, in conjunction with spin concentrations determined by e.s.r., have shown that for fresh and oxidized coal the relaxation mechanism involves spin-diffusion to paramagnetic centres and to rotating methyl groups on alkyl chains. 1H rel
1H n.m.r. spin—lattice relaxation study in bituminous coal
✍ Scribed by A. Jurkiewicz; S. Idziak; N. Piślewski
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- English
- Weight
- 319 KB
- Volume
- 66
- Category
- Article
- ISSN
- 0016-2361
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## Proton spin-lattice relaxation time constants (TV) have been found to range over more than an order of magnitude for coals of different rank'-'. Proposed relaxation mechanisms have included spin diffusion to paramagnetic centreslm3 or to rotating methyl groups5, and penetration of molecular ox
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