Fig. 2. Normal cross-polarization and magic-angle spinning (CPMAS) and dipolar dephased (DD)–total suppression of spinning sidebands (TOSS) CPMAS 13C nuclear magnetic resonance (NMR) spectra. (a) Humus. (b) Extraction residue.
Fig. 2. Normal cross-polarization and magic-angle spinning (CPMAS) and dipolar dephased (DD)–total suppression of spinning sidebands (TOSS) CPMAS 13C nuclear magnetic resonance (NMR) spectra. (a) Humus. (b) Extraction residue.