Cross-polarization/magic-angle spinning resonance

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. 

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... 

The basic spectrometer we have employed for the study of solid polymers by cross-polarization/magic-angle spinning techniques is a Nicolet TT-14 pulse-FT system operating at 1.4T with resonance frequencies of 15.087 MHz, 60.0 MHz and 56.4 MHz for 1r and... 

Zumbulyadis N. 1983. Selective carbon excitation and the detection of spatial heterogeneity in cross-polarization magic-angle-spinning NMR. J. Magn. Reson. 59 486-494. 

Figure 9.3 Conventional 13C cross-polarization magic angle spinning (CP/MAS) solid-state NMR spectra of mangrove leaves at different stages of decomposition in estuarine waters. Differences in carbon functionality are defined by the following key characteristic resonances carbohydrates (50-90 ppm) carboxyl (175 ppm) aromatic (90-170 ppm). (Modified from Benner et al., 1990.)...

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

Szeverenyi, N. M., Sullivan, M. J. and Maciel, G. E. (1982). Observation of spin exchange by two-dimensional Fourier transform carbon-13 cross- polarization— magic angle spinning. / Magn. Reson., 47,462-75. [141]... 

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