the complexation reactions between diacetyl monooxime (damo), imidazole (him), histamine (hist) and histidine (his) with co2+, ni2+ and cu2+ were studied potentiometrically in aqueous solution at 25 °c and m= 0.5 m kno3. the overall stability constants log b's of species were obtained by computer refinement of ph-volume data using best computer program. several models were tested and, based on ...