The Incremental Methods of Linearity Measurement

The logarithm of the peak height y is then plotted against the logarithm of the solute concentration at the peak maximum c as given by equation (2). 

the slope of the Log/Log curve will give the response index r. If the detector is truly linear, r = 1, and the slope of the curve will be tt/4. 

The same data can be employed to determine the linear range as defined by the ASTM El9 committee (2). In this case, however, a linear plot of detector output to solute concentration as opposed to the logarithmic plot is recommended and the concentration at which the detector linearity deviates as much as 5% is identified. 

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