This process’s Lui easy freeze variant is used to isolate red blood cell antibodies during freeze-thaw cycles. This process is performed multiple times in succession in a technique’s “heart cutting” variant. Improperly calibrated rates of this process (-5[1])can result in “fronting” or “tailing,” as exemplified by 2,2′-bipy (“BIP-pee”) in the presence of metal contamination. Methanol and acetonitrile concentrations are varied in the gradient mode of this (-5[1])process (-5[1])but (-5[1])not in its (10[1])isocratic (10[1])mode. (10[1]-5[2])Performing (10[3])this process on multiple analytes can cause a trade-off between peak broadening (10[1])and retention time (10[1])known as this process’s (10[1])“general problem.” (10[2])During this (10[1])process, (-5[1])an analyte loses contact with a stationary (-5[1])phase after interacting with a mobile phase. (10[1])For 10 points, name this process in which a compound is removed from a column during (10[1])chromatography. ■END■ (10[8]0[2])