The dimensionality of chromatographic separations

The box-counting or capacity dimension algorithm, known from the fractal mathematics literature, is used to measure the dimensionality D of chromatographic separation techniques for any number of dimensions. It is shown that D has limit properties that match Giddings' sample dimensionality s. D values are shown to be sensitive to the uniformity of peak spacing. A number of examples are given where D is calculated for various limits in one- and two-dimensional separations and for heart-cutting separations. The use of D as a quantitative measure of multidimensional orthogonality is suggested as D, due to the scale-free nature, is not dependent on the effective separation area. The connection to statistical peak overlap theory is discussed.     

Thermodynamic properties of solutions by gas chromatography using a liquid crytal compound 4,4-bis(heptyloxy)azoxybenzene as solvent

Summary Thermodynamic properties of 22 solutes at infinite dilution have been determined in the smectic, nematic and isotropic mesophases of 4,4-bis(heptyloxy)azoxybenzone. The thermodynamic properties are discussed in relation to the solute-solvent (liquid crystal) interactions as conditioned by the degree of order in the liquid crystal.