Fig. 6
From: Eco-friendly cellulose-based hydrogels derived from wastepapers as a controlled-release fertilizer
a Loading capacity of C3 cellulose hydrogel. Error bars were calculated from the standard deviations of triplicates (n = 3). b Release behavior of free urea and C3 cellulose hydrogel in water. Different letters indicate significance differences (p ≤ 0.05) between samples. c Release behavior of urea and C3 cellulose hydrogel in three types of soils. Different letters indicate significance differences (p ≤ 0.05) between samples in different soils. Error bars were calculated from the standard deviations from triplicates (n = 3)