Form UV diffuse reflectance spectra, it seems that carbonyl and phenolic groups mainly contribute to the light induced yellowing of poplar APMP.

• 紫外漫射反射光谱表明 ,杨木APMP机械浆光诱导返色的主要原因是纸浆木质素中羰基和酚羟基团吸收紫外光后变化形成发色结构所致。