Fig. 4From: Synergetic effect of dilute acid and alkali treatments on fractional application of rice straw2D-HSQC spectra and the main structures of the lignin polymers obtained from the integrated process under the various processing conditions (aromatic region). PCA free p-coumaric acid; FA ferulic acid; H p-hydroxyphenyl units; G guaiacyl units; S syringyl units; S′ oxidized syringyl units bearing a carbonyl at C α Back to article page