The quantitative aspects of cross-polarization (CP), which is used in conjunction with dipolar decoupling and magic-angle rotation to obtain high resolution 13C n.m.r. spectra of coals, have been studied using a bituminous coal (82 wt% C, dmmf basis) and asphaltenes from an extract of the same coal.
13C Solid-state n.m.r. spectra of Shanxi coals
β Scribed by Huaying Huai; Christopher J. Groombridge; Andrew C. Scott; Alec F. Gaines
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 599 KB
- Volume
- 75
- Category
- Article
- ISSN
- 0016-2361
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β¦ Synopsis
13C solid-state n.m.r, spectra of samples of 14 coals and their pyridine residues representative of the three depositions in the Shanxi province of the People's Republic of China are described in detail. The results confirm those of previous infrared spectroscopy in showing these vitrinite-inertinite coals to have similar chemical structures and aromaticities to coals of the same rank from Euramerica and Gondwana.
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