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PubMed · 8368534

Improved data-processing method for atomic absorption spectroscopy with electrothermal atomization.

C Hsiech·H L Pardue
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Abstract

A new approach is described for processing transient data from electrothermal atomizers used in atomic absorption spectroscopy. The transient responses are first integrated and then a pseudo-first-order model is fit to the time-dependent integrals in order to predict the response that would be measured if the atomization process were monitored to completion. The principal advantage expected and observed for the new approach is its ability to reduce effects of variables such as atomization temperature. For all elements studied (Cr, Mn, K, Yb, Fe), the new predictive approach is shown to be virtually independent of temperature in the range from 2200 to 2600 degrees C. The predictive approach exhibited lower temperature coefficients than either the peak-height or peak-area options for all elements examined. For the more volatile elements (Mn, K, Yb, Fe), the improvement ratio at 2400 degrees C of the predictive approach relative to the others ranged from 1.4 to 8.2. For chromium at 2400 degrees C, the temperature coefficient of the predictive method was approximately 10- and 30-fold lower than those for the peak-area and peak-height options, respectively.

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ElectrochemistryElectronic Data ProcessingSpectrophotometry, AtomicJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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C Hsiech, H L Pardue. 1993-07-15. Improved data-processing method for atomic absorption spectroscopy with electrothermal atomization.. https://doi.org/10.1021/ac00062a003

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