An on-column micro-trap was formed by cooling a short section of the open-tubular (capillary) column near the inlet. The injected sample was condensed in the trap and then heated to desorb the sample rapidly. The result was a decrease in HETP presumably due to the decrease in plug length.
No takes yet. Share an insight, caveat, or question.
Bartel et al. (1968) studied this question.