title: Spectrophotometric determination of microgram amounts of calcium in waters and foods using diphenylglyoxal bis(2-hydroxybenzoyl hydrazone).
mesh_terms: D000447:Aldehydes; D002118:Calcium / Q000032:analysis*; D005504:Food Analysis; D006835:Hydrazones; D007202:Indicators and Reagents; D008832:Microchemistry; D010658:Phenylglyoxal / Q000031:analogs & derivatives; D013053:Spectrophotometry / Q000379:methods; D014867:Water / Q000032:analysis*
chemical_list: D000447:Aldehydes; D006835:Hydrazones; D007202:Indicators and Reagents; D014867:Water; C025706:diphenylglyoxal bis(2-hydroxybenzoyl hydrazone); D010658:Phenylglyoxal; D002118:Calcium