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Nonlinear Fits of Standard Curves: A Simple Route to Uncertainties in Unknowns
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Abstract
A simple nonlinear least-squares method is described that permits direct least-squares fitting to the data of a standard curve to obtain the unknown concentration and its associated uncertainty. This procedure uses the unknown concentration as a parameter of the fit, so that it and its uncertainty are obtained immediately, bypassing the need to compute a propagation of interdependent uncertainties. Examples of the procedure, as implemented on Excel, are given for a standard additions analysis and for an analysis based on a standard calibration curve.
Keywords (Audience):
First-Year Undergraduate / GeneralKeywords (Domain):
Analytical ChemistryKeywords (Subject):
ChemometricsCiting Articles
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This article has been cited by 4 ACS Journal articles (4 most recent appear below).
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- Received: August 03, 2009
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