Nuclear magnetic resonance cross polarization

Solid-state C variable-amplitude cross polarization magic-angle spinning (VACP/MAS) nuclear magnetic resonance (NMR) spectra were acquired for the sorbitol samples. Proton decoupling was achieved by a two-pulse phase modulation (TPPM) sequence. Identical C spectra were measured for the y-form sorbitol samples, and a representative spectrum is shown in Figure 9. 

We have been interested in the nature of cooperative motions in polymers for some time and have used carbon-13 nuclear magnetic resonance for examining main-chain motions in solids (22-27). Carbon-13 nmr with cross-polarization and magic-angle... 

Both of these methods have been used for DOM isolation from major rivers and the surface ocean, and the general characteristics of these fractions of DOM are presented in Table I. The major C functional groups of humic substances and ultrafiltered DOM (UDOM) have been characterized by solid-state, cross-polarization magic angle spinning 13C nuclear magnetic resonance (NMR) spectroscopy. The samples of humic substances that were characterized by NMR spectroscopy were collected from the Amazon River... 

Preston, C.,Trofymow, J., Sayer, B., and Niu, J. (1997). 13C nuclear magnetic resonance spectroscopy with cross-polarization and magic-angle spinning investigation of the proximate-analysis fractions used to assess litter quality in decomposition studies. Can. J. Bot. 75, 1601-1613. 

Wilson, M. A., Barron, P.F., and Goh,K.M. (1981b). Differences in structure of organic-matter in 2 soils as demonstrated by l3C cross polarization Nuclear magnetic-resonance spectroscopy with magic angle spinning. Geoderma 26, 323-327. 

Cross Polarization Magic Angle Nuclear Magnetic Resonance 505... 

Physicists have long been aware of the power and usefulness of high-resolution solid-state NMR. Even prior to the development of cross-polarization, in the early to mid-seventies, it was clear that, by recording the nuclear magnetic resonance spectrum when the sample was spun at the magic angle (5 M1) to the magnetic field, chemical shifts could be readily identified... 

Haw JF, Maciel GE, Schroeder HA (1984) Carbon-13 nuclear magnetic resonance spectrometric study of wood and wood pulping with cross polarization and magic-angle spinning Anal Chem 56 1323-1329... 

Cross Polarization/Magic Angle Spinning Nuclear Magnetic Resonance (CP/MAS NMR) Spectroscopy... 

Morgan KR, Newman RH (1987) Estimation of the tannin content of eucalypts and other hardwoods by carbon-13 nuclear magnetic resonance Appita 40 450-454 Newman RH (1987) Effects of finite preparation pulse power on carbon-13 cross-polarization NMR spectra of heterogeneous samples J Magn Reson 72 337-340 Newman RH (1989) Carbon 13 NMR studies of lignin in solid samples - a review Chemistry Division Report, DSIR, New Zealand... 

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