Evaluating the Holdup Time of Gas-Chromatographic Systems in Various Temperature Regimes by Using Recurrent Relations

Abstract

The new algorithm for evaluating the holdup time of gas-chromatographic systems (t 0 ) is considered. It is applicable at any temperature regimes of analysis not only isothermal, but also with linear temperature programming. It is based on the extrapolation of retention times of consecutive homologues (in particular, n-alkanes) with the evaluation of retention time of hypothetical homologue with zero number of carbon atoms in the molecule by using linear recurrent relations. It is shown that historically first method for evaluating t 0 using retention times (t R ) of three consecutive homologues, proposed by Peterson and Hirsch (J Lipid Res 1:132-144, 1959), can be expanded onto temperature programming regimes after its modification by replacing t R values by their squares.

Anomalous temperature dependence of gas chromatographic retention indices of polar compounds on non-polar stationary phases

“…The values of hold-up time (t 0 ) were calculated using retention times of three consecutive n-alkanes С 6 -С 8 by the method of Peterson and Hirsch modified for using recurrent dependences [25]. The logarithmic (Kováts) retention indices at isothermal conditions were calculated using QBasic program.…”

Overloading control of gas chromatographic systems

“…The values of hold‐up time ( t 0 ) required for precise calculation of Kovats′ retention indices were evaluated using retention times of three consecutive n ‐alkanes C 6 –C 8 by the method of Peterson and Kirsch in the mode of recurrent relations according to . Evaluation of the values of asymmetry factor A * (the ratios of the areas of two parts of chromatographic peaks separated with perpendicular from the point of maximum to the baseline, see Fig.…”