The rapid development of new instrumental techniques in analytical applications of atomic-absorption flame photometry, besides the use of emission flame photometry in research and routine analysis, leads continuously to new areas in which new or modified computer techniques can be used for the reduction of data and for easier and more accurate obtaining of results.
Since the application of computer techniques in flame photometry problems was discussed previouslyi, new techniques have been developed. These are summarized in the present paper and some examples are given as a complement to the techniques previously described. Most of the techniques described, that require plotting of the final results, refer to two-dimensional plots of the dependent variable as a function of an independent variable fixed at the operator's choice, with all other variables existing in the chemical system held constant during the experiment.
Two of the cases described, calibration curves and flame profiles, can be considered together since they are based on the use of three variables, with one held constant in each case. l?or calibration curves, the variation of absorbance as a function of analyte concentration with the elevation of the burner held constant is measured, whereas for flame profiles variation of absorbance as a function of burner elevation with the analyte concentration held constant is measured. A set of experimental values obtained by measuring the signals of several standards of analyte concentration at consecutively increasing burner elevations provides the operator with three variables. Hence, it is possible to represent calibration curves, flame profiles and three-dimensional plots". EXPERIMENTAL Instrumentation For com@&ng and #Zotting techniques. (a) IBM System 360, Model 40, 256K memory. In previous workr, an IBM 1410, 4oK memory was used but was later replaced with the present system. (b) CalComp Digital Plotter, Model 565. (c) IBM 2250, Model I cathode-ray tube on-line display scope with alphameric keyboard, light pen and function keys.
For flame fdtotometry techniques. (a) Beckman DU * flame spectrophotometer with A.C. power supply, SERA, and IO-in Bristol recorder. (b) Beckman DU @-z