Fig. 5From: Toward an understanding of the increase in enzymatic hydrolysis by mechanical refiningSum frequency generation (SFG) spectra for unrefined and refined pretreated sugarcane bagasse after PFI and disc refining at different intensity levels. a, b The normalized SFG spectra for PFI- and disc-refined samples, respectively. c SFG CH/OH peak area ratio calculated from normalized SFG spectra. SFG results are the average of triplicatesBack to article page