Fig. 1
From: Replacing process water and nitrogen sources with biogas slurry during cellulosic ethanol production
Visualization of corn straw by tabletop microscopy (× 500). a Untreated corn straw, and b corn straw pretreated with biogas slurry, and c corn straw pretreated with fresh water for 6 h at 140 °C with 1.34% NaOH (w/v) and 100 g L−1 substrate concentration