Solid-state carbon-13 nuclear spectroscopy

Inbar, Y., Chen, Y., and Hadar, Y. (1989). Solid-state carbon-13 nuclear magnetic resonance and infrared spectroscopy of composted organic matter. Soil Sci. Soc. Am. J. 53, 1695-1701. 

Simpson, M. J., and Hatcher, P. G. (2004). Determination of black carbon in natural organic matter by chemical oxidation and solid-state 13C nuclear magnetic resonance spectroscopy. Org. Geochem. 35, 923-935. 

Knicker, H. (1999) Biogenic nitrogen in soils as revealed by solid-state carbon-13 and nitrogen-15 nuclear magnetic resonance spectroscopy. Journal of Environmental Quality, 29, 715— 723. 

Usami T, Itoh T, Ohtani H, Tsuge S, Structural study of polyacrylonitrile fibers during oxidative thermal degradation by pyrolysis- gas chromatography, solid-state C nuclear magnetic resonance and Fourier transform infrared spectroscopy. Macromolecules, 23, 2460 465, 1990. Bhat GS, Cook FL, Abhiraman AS, Peebles LH Jr., New aspects in the stabilization of acrylic fibers for carbon fibers. Carbon, 28(2,3), 377-385, 1990. 

Compilation of Experimental Reports on Solid-State NMR (Nuclear Magnetic Resonance) Spectroscopy Applied to the Study of Carbon Materials... 

Similar methods are available that are based on solid-state proton nuclear magnetic resonance spectroscopy. Proton methods are less discriminating than the equivalent carbon-13 method, being based on a two-phase model of semicrystalline morphology. In their favor, they are several orders of magnitude faster than the carbon-13 method and the equipment required is much cheaper. 

The application of nuclear magnetic resonance (NMR) spectroscopy to polymer systems has contributed to significant advances in understanding of their structure and dynamical properties at the molecular level. From the analytical point of view, NMR spectroscopy is particularly suitable for a determination of the polymer structure by direct observation of the protons and carbons in different structural moieties. However, until the mid-1970s the application of this technique was limited to polymer solutions and to some elastomers in the solid state with a relatively high degree of the molecular mobility which allows the observation of the motionally narrowed absorption signals. 

Hays GR. 1982. High resolution carbon-13 solid-state nuclear magnetic resonance spectroscopy. Analyst 107 241-252. 

It is well known that nmr is a powerful means for the study of the dynamics of polymer chains both in solution and in the solid state. The relaxation of 13C nuclei has been extensively employed for this purpose in this and other laboratories. I illustrate here a dilferent and particularly intriguing approach which as yet has seen only very limited application to synthetic polymers. This is deuterium quadrupolar echo spectroscopy, as employed in our laboratory by Dr. Lynn Jelinski and her collaborators (20). The presence of the nuclear electric quadrupole lifts the degeneracy of the two deuterium Zeeman transitions, and in the solid state produces a very broad (ca 200 kHz) powder pattern of transitions which can be interpreted to yield very specific motional information for those carbons labelled with deuterium. In Figure 7 are shown spectra of poly (butylene terephthalate) deuterated on the central carbons of the aliphatic chains ... 

Nuclear magnetic resonance spectroscopy ( C CP/MAS Solid State NMR) and Fourier transform infrared spectroscopy (FT-IR) were also performed for the freeze dried NOM sample. The results were both very noisy and paramagnetic compounds such as iron and manganese interfered with the - C NMR analysis. After 20 h of run time the sample showed mostly alkyl and alkyl-oxygen carbon, thus very little aromatic compounds. 

R., A Study of Carbon and Hydrogen Aromaticity in Coals by High Resolution Solid State Nuclear Magnetic Resonance and Fourier Transform IR Spectroscopy, (to be published)... 

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