The spectrochemical analysis of solutions offers such a variety of advantages that a number of techniques have been developed and reported in the literature. There has been little or no intercomparison of the procedures or excitations, so it has been difficult to select one technique in preference to another. This paper describes studies of five different solution techniques and three excitation conditions A number of observations are reported regarding general conditions to give the best sensitivity and reproducibility. The effects of hydrochloric, nitric, sulfuric, and phosphoric acid on the spectra were also studied. The repression effects which were noted for some acids varied with the technique, acid concentration, and excitation potential of the line.
William K. Baer and Edwin S. Hodge, "The Spectrochemical Analysis of Solutions. A Comparison of Five Techniques," Appl. Spectrosc. 14, 141-146 (1960)