Fig. 7
From: Impacts of hydrous manganese oxide on the retention and lability of dissolved organic matter

a Scanning transmission X-ray microscopy-Mn L-edge NEXAFS spectra for the DOM–HMO complexes with initial C:Mn molar ratios of 0.46 and 2.5 (solid lines), as well as the linear combination fits (dashed lines). The unreacted HMO spectrum and reference spectra for Mn oxide standards from Gilbert, Frazer [73] are provided for comparison. b Scanning transmission X-ray microscopy-Fe L-edge NEXAFS spectra for goethite with initial C:Fe molar ratios of 0.23 and 3.1 Iron(II) and Fe(III) reference spectra are shown for comparison