Continuous affinity spectrum using

FIGURE 11.6 Sorption isotherms of dodecylpiridinium on a soil material (EPA-12). (a) Points experimental data line fitted isotherms (almost indistinguishable) with discrete and continuous affinity spectra (b) discrete affinity spectrum, found using regularization for a small number of sites (c) continuous affinity spectrum, after regularizing for smoothness note that the smaller peaks are magnified by a factor of 30. (Reprinted with permission from Cernik, M. et al.. Environ. Sci. TechnoL, 29,2,413-425. Copyright 1995 American Chemical Society.)... 

A variety of alternative models more realistic than the Langmuir isotherm may be used to fit the isotherm data the most accurate but most demanding (in terms of amount and accuracy of data required) is the affinity spectrum approach, which yields a continuous spectrum of number of binding sites vs. [27]. The simplest approach, however, is to model the isotherm as resulting from just two classes of binding site ... 

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