Wallace R. Brode

The Influence of Extraneous Elements on Line Intensity. IV. Extraneous Element Effects in the Direct-Current Arc*

The effect of varying amounts of extraneous element upon the line intensity of different elements has been investigated. Slavin’s total energy method was used to make possible a more direct correlation than has been achieved using the internal standard method. The results of this study indicate that the effect of the extraneous element varies with the amount of extraneous element, but not in a simple linear fashion. The effect of an extraneous element on a group of lines of an element ending at the same energy level or beginning at the same energy level, is the same.The experimental results show that the elements can be arranged in a series bases on their interelement effects in the d.c. arc. An arrangement of the elements in a series based on their boiling points and excitation potentials is in agreement with that found experimentally.

Studies on the chemistry of the fatty acids VIII the reaction of thiocyanogen with linoleic and linolenic acids

SummaryThe thiocyanogen reagent may be stabilized by storage at temperatures of 3° or less. The reaction of thiocyanogen with highly purified linoleic and linolenic acids has been studied under many variations of experimental conditions. Reaction rates of thiocyanogen with oleic, linoleic and linolenic acids at 3°, 16° and 25° and with variable excess of reagent are described. Oleic acid gives a maximum thiocyanogen absorption which is apparently equal to the iodine number, within 3–6 hours. The reaction with linoleic acid is rapid up to 3 hours and shows a slow constant increase thereafter. A modified procedure of analysis, similar to the official method, employs a 0.2 N thiocyanogen reagent, containing 10 percent carbon tetrachloride and a reaction temperature of 16°. Results of analysis of several specimens of acids by several preparations of reagent shows an average thiocyanogen value of 96.6 for linoleic acid and 166.3 for linolenic. Simultaneous equations, derived from these values, were used in the analysis of five mixtures of known composition with excellent results.