An integrated-intensity method for emission spectrographic computer analysis

Catharine P. Thomas

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USGS · 70164421

An integrated-intensity method for emission spectrographic computer analysis

Catharine P. Thomas

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Abstract

An integrated-intensity method has been devised to improve the computer analysis of data by emission spectrography. The area of the intensity profile of a spectral line is approximated by a rectangle whose height is related to the intensity difference between the peak and background of the line and whose width is measured at a fixed transmittance below the apex of the line. The method is illustrated by the determination of strontium in the presence of greater than 10 percent calcium. The Sr 3380.711-A line, which is unaffected by calcium and which has a linear analytical curve extending from 100-3,000 ppm, has been used to determine strontium in 18 standard reference rocks covering a wide range of geologic materials. Both the accuracy and the precision of the determinations were well within the accepted range for a semiquantitative procedure.

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Catharine P. Thomas. 1975. An integrated-intensity method for emission spectrographic computer analysis. https://pubs.usgs.gov/publication/70164421

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