Fig. 1From: Solid-Phase Spectrophotometric Analysis of 1-Naphthol Using Silica Functionalized with m-Diazophenylarsonic AcidUV–vis absorption spectra of 5 × 10−4 M solution of m-APAA at different рН: (1) 2.0, (2) 4.0, (3) 9.0, and (4) DR-UV spectrum of SiO2 –APAABack to article page