Assertion: lignin's group | /r/HasProperty | o-h stretching
Facets:
Source sentences:
text: In the spectrum there was evidence of the efficiency of our direct esterification (catalyst-free esterification) toward the hydroxyl groups in HELignin, as illustrated by a clear reduction of hydroxyl group (O-H stretching, 3,650–3,200 cm−1) absorbance.