CPMAS NMR spectra

Solid state 13C CPMAS NMR spectra of Wheat High Molecular Weight (W.HMW) subunits show well resolved resonances identical with spectra of dry protein and peptide samples [24], Most of the amino acids side-chain resonances are found in the 0-35 ppm region followed by the alpha resonances of the most abundant amino acids glycine, glutamine and proline at chemical shifts of 42, 52 and 60 ppm, respectively, and the carbonyl carbons show a broad peak in 172-177 ppm region. The CPMAS spectra of hydrated whole HMW provides important information on the structural characteristics. 

Figure 11 The SRI plots of the 13C DDMAS NMR spectra of (A) PMEA (containing 7 wt% water), (B) PHEMA gels (containing 40 wt% water), CPMAS NMR spectra of (C) PMEA, and (D) PHEMA gels against temperature. Suppression temperatures Ts at which respective peaks are most reduced are shown by the arrows. From Ref. 29 with permission.

Figure 12, 3C CPMAS NMR spectra for the PVA gels with different polymer concentrations. The polymer concentrations are (A) 9.1, (B) 11.8, (C) 13.8, and (D) 35% (wt/wt%), respectively. From Ref. 100 with permission.

Figure 24 (A) 13C DDMAS and (B) CPMAS NMR spectra of [3-BC]Ala-labelled bR from...

Figure 31 100.6 MHz 13C CPMAS NMR spectra of [l-13C]Val-labelled D85N mutant at...

Figure 35 13C CPMAS NMR spectra of [l- 3C]Val- and [3- 3C]Ala-labelled bR reconstituted in DMPC bilayer (1 50 mole ratio) at various temperatures from 40 (A) to —10 °C (D). The methylene peak-position of the fatty acyl chain of the lipid at 32 and 30 ppm is a good indicator of the gel and liquid-crystalline phase, respectively. From Ref. 206 with...

Figure 39 BC CPMAS NMR spectra of [3- 3C]Ala-labelled ppR (a), A149S (b) and A149V (c) reconstituted in egg PC bilayer. 13CNMR signal at 15.9 ppm corresponding to Alal49 in ppR is shown by the grey (a) and arrows (b, c, and d). The resonance peak at 14.1 ppm is ascribed to methyl carbon peak of egg PC as shown as asterisk. Difference spectrum between (a) and (c) is shown in (d). From Ref. 214 with permission.

NMR spectroscopy (31P, II, 13C) and mass spectrometery have been extensively employed for establishing structures of the diazaphospholes. The solid state 13C and 15N CPMAS NMR spectra of 3,5-di-substituted [l,2,4]diazaphospholes have been recorded [78]. Several X-ray crystal structures have been reported for a number of... 

The results of these studies are summarized in Table 13. Some typical 29Si CPMAS NMR spectra are displayed in Figures 28-30. 

FIGURE 51. 29Si CPMAS NMR spectra of Aerosil A-200 with trimethylsiloxane surface coverage and chemical shifts of the peak maxima ( maximum error) as indicated. All spectra are on the same intensity scale. Reproduced by permission of Elsevier Science from Reference 152... 

Chemical shifts of 13C CPMAS NMR spectra of 4-(4-fluorophenyl)-2- 4-[4-(3-trifluoromethylphenyl)piperazino]butyl -2,3-dihydro-lH-pyrido [l,2-c]pyrimidinel,3-dione and its hydrochloride salt were unambiguously assigned by theoretical calculations at GIAO/DFT (B3LYP/6-311 +G ) level (08JST325). Absolute energies, bond angles, and bond distances of 9,10-dimethoxy-l, 6,7,11 fc-tetrahydro-2H,4H-[l, 3]oxazino[4,3-fl]... 

Polymerization of pyrogallol (measurement of optical density) ring cleavage of pyrogallol and catechol (measurement of C02 release) yields of humic polymers IR and 13C CPMAS NMR spectra resembling natural HAs... 

Birnessite (8-Mn02) Condensation of glucose and glycine under soil ambient conditions (measurement of optical density) yields of humic substances XANES study of change in speciation of Mn ESR study of Mn speciation in solution 13C CPMAS NMR spectra of FA fraction resembling spectra of natural FAs Jokic et al. (2001b)... 

Figure 15.8. 13C CPMAS NMR spectra of the IHSS Pahokee Peat and a Canadian Grassland (black chernozem) soil and their corresponding humin samples. Reprinted from Simpson, M. J., and Johnson, P. C. E. (2006). Identification of mobile aliphatic sorptive domains in soil humin by solid-state 13C nuclear magnetic resonance. Environ. Toxi. Chem. 25, 52-57, with permission from the Society of Environmental Toxicology and Chemistry.

Schmidt, M., Knicker, H., Hatcher, P., and Kogel-Knabner, I. (1997a). Improvement of 13C and 15N CPMAS NMR spectra of bulk soils, particle size fractions and organic material by treatment with 10% hydrofluoric acid. Eur. J. Soil Sci. 48,319-328. 

Spaccini, R., Piccolo, A., Haberhauer, G., and Gerzabek, M. H. (2000). Transformation of organic matter from maize residues into labile and humic fractions of three European soils as revealed by C-13 distribution and CPMAS-NMR spectra. Eur. J. Soil Sci. 51, 583-594. 

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