Assertion: lignin's unit | /r/HasProperty | difference
Facets:
Source sentences:
text: The content of hydroxyl groups was obtained by integration of the following spectral regions: aliphatic hydroxyls (149.4–145.5 ppm), syringyl (S) phenolic hydroxyls (143.3–141.9 ppm), condensed phenolic units (difference between 144.3–141.3 ppm and 143.3–141.9 ppm as previously done by Cateto et al.