“…Tailing peaks are consequently obtained when nonlinearity is not of importance. Although concentration phenomena have been dealt with in a considerable number of treatments of frontal analysis (16, 18, 27), relatively few attempts have been made to incorporate either sorption (1,11,22) or nonlinear (7,8,16) effects in theories of nonideal elution development, probably as a result of mathematical difficulties. Houghton (16) recently made a very important advance by obtaining a closed expression for the elution curve of a single solute which takes nonlinearity as well as nonideality into account.…”