A proposal for upgrading the National-Scale Soil Geochemical Database for the United States
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Geology topics
Michael A. Wilson
Publications and source records attributed to Michael A. Wilson.
The effect of sample hydration on 13C CPMAS NMR spectra of fulvic acids
Three fulvic acids, two of which have been well studied by a number of other groups (Armadale and Suwannee river fulvic acids) have been examined by high resolution solid-state 13 C-NMR techniques to delineate the effect of absorbed water. Two main effects of absorbed water were observed: (1) changes in spin lattice relaxation times in the rotating frame and cross polarization times and (2) total loss of signal so that some fulvic acid is effectively in solution. These results suggest that discrepancies in the literature concerning observed relative signal intensities from different structural groups are due to absorbed water and emphasize the necessity for proper precautionary drying before spectroscopic analysis.
Organic Geochemistry↗