Abundant mineral content and characteristic IR absorption bands

1 Abundant mineral content and characteristic IR absorption bands 

2 Comparison of pyrolysis mass spectra for aqueous soil extract, fulvic acid, and water-soluble humic acid 

and 84 m/z (ethene to hexene). They were probably derived from aliphatic acids, as evidenced by the fragment series at 43, 57, 

Soil fulvic acid (Fig. 5.2(B)) shows dominant signals similar to those observed in a complex polysaccharide spectrum (ref. 359), with peaks at 68, 82, 84, 96, 98, 110, 112, 114, 126, and 128 m/z. In addition, nitrogen-containing fragments are low. Evidence of polysaccharide is also shown in the spectrum of a water-soluble fraction of humic acid (Fig. 5.2(C )), isolated by gel filtration (ref. 362). However, the presence of homologous ion series of sulfides (34, 48 m/z), pyrroles (67, 81, 95 m/z), pyridine (79 m/z), benzenes (78, 106 m/z), phenols (94, 108, 122 m/z), indole (117 m/z), and lignin-derived units (124, 138, 150 m/z) with variable intensity, 

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