Direct-reading spectrometric

Quantitative spectrographic analyses for trace elements in high-temperature ash samples of coal have been reported by Abemethy et ah (1), Zubovic et ah (2,3,4,5), Rao (6), and Hunter and Headlee (7). We felt that it was desirable to develop additional analysis methods, especially for the direct-reading spectrometric technique, in which small changes of some matrix constituents might cause relatively large variations in results because of the increased sensitivity of the detection system. A... 

Preparation of Direct-Reading Spectrometric Standards. No certified standards are yet available for trace elements in coal, although the National Bureau of Standards is conducting an inter laboratory evaluation of a composite coal sample for use as a Standard Reference Material (11). It was necessary, therefore, to prepare synthetic standards. 

The nicest possible summary of the transformation in instrumentation and objectivity can be read off a 1959 advertisement. In 1959 BA advertised their spectrometers by comparing analytical methods, wet chemistry, spectrographic methods, and direct reading (figure 6.1). An iconic summary was presented for each approach. As with any effective ad, the visual point is made quickly and clearly wet chemical analysis takes more steps than spectrographic analysis, which itself takes more steps than spectrometric analysis (using a direct reader). Furthermore, the steps involved are easier with spectrographic methods than with wet chemical analysis, and easier still with spectrometric methods. 

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