Fig. 1From: Novel allyl-hydrazones including 2,4-dinitrophenyl and 1,2,3-triazole moieties as optical sensor for ammonia and chromium ions in waterUV–Vis spectra of compound 4a in the presence of a NH4OH and K2CrO4 and b ZnCl2, AlCl3, HgCl2, NiCl2, MnCl2, SnCl2 and compound 4b in the presence of c NH4OH and K2CrO4 and d ZnCl2, AlCl3, HgCl2, NiCl2, MnCl2, SnCl2Back to article page