𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Prospects for carbon-13 nuclear magnetic resonance analysis of solid fossil-fuel materials

✍ Scribed by Victor J. Bartuska; Gary E. Maciel; Jacob Schaefer; Edward O. Stejskal

Publisher
Elsevier Science
Year
1977
Tongue
English
Weight
595 KB
Volume
56
Category
Article
ISSN
0016-2361

No coin nor oath required. For personal study only.

✦ Synopsis

Because of excessive line broadening in solids due to magnetic dipole-dipole interactions and chemical shift anisotropies, and because of long spin-lattice relaxation times, standard continuous wave (CW) or pulse Fourier transform techniques do not normally yield structurally informative 13C n.m.r. spectra from solid samples. However, the techniques of dipolar decoupling, cross polarization and magic-angle spinning show great promise for routine 13C n.m.r. studies of solids. Applications of these techniques to analysis of anthracite, lignite and algal coal samples, and to oil shale and kerogen samples, are discussed. It is shown that cross-polarization spectra obtained with dipolar decoupling display chemical shift anisotropy which interferes with attempts to distinguish the resonances of aromatic and aliphatic carbons. However, with magic-angle spinning the distinction can be made. Prospects and potential difficulties with applications of these techniques are discussed.

📜 SIMILAR VOLUMES

Sequence analysis of ethylene sulphide-p
Sequence analysis of ethylene sulphide-propylene sulphide copolymers by carbon-13 nuclear magnetic resonance
✍ C. Corno; A. Roggero; T. Salvatori 📂 Article 📅 1974 🏛 Elsevier Science 🌐 English ⚖ 254 KB

Ethylene sulphide-propylene sulphide copolymers, prepared with anionic type catalysts, have been investigated by t3C NMR. The peaks have been assigned both in terms of diad and triad monomer sequences and in terms of tacticity. It has been shown that the propylene sulphide monomer units were directi

Quantitative analysis of pyrrolizidine a
Quantitative analysis of pyrrolizidine alkaloid mixtures from Senecio vulgaris by carbon-13 nuclear magnetic resonance spectroscopy
✍ L. A. C. Pieters; A. J. Vlietinck 📂 Article 📅 1987 🏛 John Wiley and Sons 🌐 English ⚖ 294 KB 👁 1 views

A I3C NMR method has been developed for obtaining simultaneously structural and quantitative information on mixtures of pyrrolizidine alkaloids from Senecio vulgaris L. (Compositae). The samples contained seneciphylline, senecionine, retrorsine and the corresponding E geometrical isomers, spartioidi

Carbon-13 nuclear magnetic resonance stu
Carbon-13 nuclear magnetic resonance studies of anthraquinones. IV—correlation of substituent effects for 1-substituted anthraquinones
✍ Y. Berger; M. Berger-Deguée; A. Castonguay 📂 Article 📅 1981 🏛 John Wiley and Sons 🌐 English ⚖ 329 KB

## Abstract The spectra of various 1‐substituted and 1,5‐disubstituted anthraquinones have been studied and the chemical shifts of the different carbon nuclei determined. The chemical shifts previously reported for 1‐Me‐anthraquinone have been corrected and reassigned. The C‐1, C‐4 and C‐13 shifts

Regiospecific analysis of natural mixtur
Regiospecific analysis of natural mixtures of triglycerides using quantitative 13C nuclear magnetic resonance of acyl chain carbonyl carbons
✍ Giovanna Vlahov 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 167 KB 👁 2 views

High-resolution 13C NMR spectroscopy of the carbonyl carbons of triglyceride acyl chains was used as a quantitative method for the regiospeciÐc analysis of the triglyceride fraction of vegetable oils of di †erent botanical origins. The carbonyl carbon resonances of saturated, oleyl and linoleyl chai

Carbon-13 nuclear magnetic resonance stu
Carbon-13 nuclear magnetic resonance studies of anthraquinones. Part III—correlation of substituent effects for 2-substituted anthraquinones
✍ Y. Berger; M. Berger-Deguée; A. Castonguay 📂 Article 📅 1981 🏛 John Wiley and Sons 🌐 English ⚖ 383 KB

The 13C chemical shifts of 2-substituted and 2,6-disubstituted anthraquinones have been determined and assigned. The C-l,2,3,4,13 and C-14 chemical shifts of 2-substituted anthraquinones are correlated with the chemical shifts of monosubstituted benzenes. A three-parameter correlation with Swain and