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1H n.m.r. relaxation in bituminous coal and semicoke

✍ Scribed by John A. Ripmeester; Christiane Couture; J.Anthony MacPhee; Biswanath N. Nandi

Publisher
Elsevier Science
Year
1984
Tongue
English
Weight
291 KB
Volume
63
Category
Article
ISSN
0016-2361

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✦ Synopsis

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 relaxation in semicokes is more complex; probably both direct relaxation to paramagnetic centres as well as spin-diffusion contribute.

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