Application of new expansion pretreatment method on agricultural waste. Part I: Influence of pretreatment on the properties of lignin

Side chain (δC/(δH 45-90/2.6-6.0) and aromatic (δC/δH 90-150/6.0-8.0) regions in the 2D HSQC NMR spectra of lignin fractions L1 and L3.