Correlation of characteristic thermal constant and elution temperature in GC

In a temperature-programmed analysis, the solutes that elute at higher temp eratures have generally larger characterisitic thermal constants, theta (ch ar). The change approximately matches the temperature-related increase in a carrier gas viscosity. Accounting for the effect allows reduction in the u ncertainty of prediction of theta (char) by a factor or f similar to2 and, in a constant-pressure mode, description of a linear heating ramp by the sa me dimensionless rate for all solutes.