Abstract
A Spectrochemical addition method capable of alalysing the trace impurities in the order of 10−5% was studied, that is: (1) The width of “A” range, in which the light exposure on photographic emulsion is proportional to the opacity of developed plate, was examined from 2250 Å to 3500 Å, at very low intensity of incident light. (2) A foundamental theory of spectrochemical addition method in this range, including background correction,was derived. (3) The analytical procedures, applicable to industrial routine analysis, with attention to the precision and its control, were studied. The proposed method enables analyses of Cd, Fe,Sn and Pb in Zinc down to 0.0001%, with variation coefficient of 15%.
