ANALYTICAL CHEMISTRY
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(2) Gliok, D.. and Alalmstrom, B. G.. Ezgl. Cell. Research, 3, 125
(1952).
(3) Elosdorf, E. W., "Freese Drying." New York, Reinhold Publishing Corp.. 1949. (4) Makower, B., and Nielsen. E., ANAL.CBEM.,20, 856 (1948). (5) Rogers, C. J., private oommunication. 1954. (6) Zamuow, W.H., and Marshall, W. R., Chon. E w , Progr., 48, 21 (1952).
Calculator for Use with Fluorescent Indicator Adsorption Method. W. H. Ellis, California Research Corp., Richmond, Calif. ALcuLATrnN
of results requires
8
msjm part of the time in-
C volved in making chromatographic analyses of liquids by the fluorescent indicator adsorption method (23). I n the past, the calculation of such analyses has been accomplished by measuring the position of zone boundaries in centimeters, subtracting to obtain the length of each zone, and dividing the zone length by the total length of the sample in the column to obtain the percentage of each component. A device has been designed and constructed to reduce the calculation time by eliminating the division step. The apparatus is a proportional divider of the right-trapezoid type. The top and bottom of the trapezoid, 50 and 80 em. in length, respectively, and 48 em. apart, are each divided into 100 equal divisions representing percentages, and corresponding points on the two lines are joined. The FIAM column is marked while under ultraviolet light and then laid on the chart with the lower and upper marks on the column directly over the 0 and 100% lines, respectively, of the chart. The column must he perpendicular to the 0% line. Percentages corresponding to the intermediate marks an the column can then he read directly from the chart. The chart has lines 1%apart, and every tenth line is numbered. For convenience in reading, thc linen are numbered nt several places across the chart. constantan thermaeo
