Multiple Cole system

With measured data showing a nonsymmetrical DRT, the choice of model is important for example, a model according to this section or a model with multiple Cole systems (see the next section). 

With a given data set obtained from measurements, it must be decided how the data are to be interpreted and presented (see Section 9.1). This immediately leads to the question of which model should be chosen. The same data can be interpreted using Cole variables such as a and t, but also with many non-Cole models as explained in earlier chapters. As we shall see, many datasets can be explained with multiple dispersions, for example, multiple Cole systems. As we now present multiple Cole systems, it must always be kept in mind that the tissue dataset certainly could have been made to fit other models. The ability to fit the multiple Cole model to the data set is not a proof that this model is the best one for describing, or explaining, the data found. Skin is, for instance, used as an example in this chapter, and we know that skin data are not necessarily in agreement with the Cole—Cole model. 

Water-in-oil solubilized adjuvant formulations of vaccines containing Clostridium welchii type D toxoid as antigen were prepared first in 1968 and tested in laboratory animals by Coles et al [238]. The adjuvant action of oil-in-water emulsions, multiple emulsions and water in gelled oil emulsions is well known but these varied systems have the disadvantages of high viscosity which makes injection physically difficult. Lin [236] quotes an HLB of 9.7 as the optimum value for water solubilization in mineral oil. Coles et al [238] found a value of 10. While the addition of a small quantity of the lipophilic surfactant Arlacel 80 (sorbitan mono-oleate) to a system of Tween 81 (polyoxyethylene (5)-sorbiton mono-oleate) alio wed increasing amounts of water to be solubilized, when toxoid solution was substituted for water the Arlacel decreased the amount which could... 

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