Peak height, analytical significance

The repeatability of gas sample separation is presented in Fig. 6.12. The separation peaks of the mixed gaseous analytes match those for each individual analyte quite well, irrespective of the analyte concentration, which correlates to the peak height (Fig. 6.12a, b). Although manual sample injection may introduce a certain degree of variation in retention time measurement, using a gas marker can significantly improve such measurement, as demonstrated in Fig. 6.12c, in which decane is used as a marker. 

Due to the presence of the internal standard, it is critical to ensure that the analyte peak be separated from the internal standard peak. A minimum of baseline separation (resolution >1.5) of these two peaks is required to give reliable quantitation. In addition, to quantitate the responses of internal standard accurately, the internal standard should be baseline resolved from any significant related substances and should have a peak height or area similar to that of the standard peak. 

As discussed by Tercier and Buffle [116], when trying to carry out ASV in samples of low or variable ionic strength, it can be difficult to correlate peak heights and analyte concentration. This difficulty arises because counterion transport is coupled to oxidation of the metal that is concentrated within the mercury or polymeric film. Therefore, the peak height, width, and position can depend significantly on the identity and concenhation of the counterions in the sample. 

AAS because the analyte concentration is small. However, Lorentz broadening, which involves collisions between analyte atoms and foreign species (Ar atoms in electrothermal atomizers) called perturbers, are significant. Compared to a Doppler spectral profile, the Lorentzian profile is broader, has a lower peak height and is described by a Lorentzian function f(curve L in Figure 5) with the FWHM given by ... 

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