Property/composition mapping

Property/Composition Mapping and Structure-Property Relationships... 

Fig. 19.8 Property/composition mapping of solvent-resistance of BPA-HQ-RS copolymers in different solvents (a) THF, (b) chloroform, (c) MEK. Numbers in the contour lines are normalized sensor frequency shift values (Hz per mg of polymer in a well). Reprinted with permission from Potyrailo et al.23 Copyright 2006 American Chemical Society...

Composition map a means of illustrating the chemical make-up of petroleum using chemical and/or physical property data. 

Though the variables A and B have been treated differently in the foregoing, their roles are essentially equivalent. Indeed, there is a universal property analogous to (the dual of) that in (2.4.4), characterizing the natural composite map of A-functors from K x K to D ... 

The previous section depicted the general patterns of ehange on a formulation composition map. Actual values of the properties, particularly of minima and maxima, as well as formulation and composition scale characteristics, may be changed by other factors. 

We have shown that the current state of the art in emulsion science, particularly the formulation-composition mapping of emulsion properties, is general know-how that may he segregated into basic operations for the formulation engineering approach to emulsion making. 

The transformed variables describe the system composition with or without reaction and sum to unity as do Xi and yi. The condition for azeotropy becomes X, = Y,. Barbosa and Doherty have shown that phase and distillation diagrams constructed using the transformed composition coordinates have the same properties as phase and distillation region diagrams for nonreactive systems and similarly can be used to assist in design feasibility and operability studies [Chem Eng Sci, 43, 529, 1523, and 2377 (1988a,b,c)]. A residue curve map in transformed coordinates for the reactive system methanol-acetic acid-methyl acetate-water is shown in Fig. 13-76. Note that the nonreactive azeotrope between water and methyl acetate has disappeared, while the methyl acetate-methanol azeotrope remains intact. Only... 

Now, we should ask ourselves about the properties of water in this continuum of behavior mapped with temperature and pressure coordinates. First, let us look at temperature influence. The viscosity of the liquid water and its dielectric constant both drop when the temperature is raised (19). The balance between hydrogen bonding and other interactions changes. The diffusion rates increase with temperature. These dependencies on temperature provide uS with an opportunity to tune the solvation properties of the liquid and change the relative solubilities of dissolved solutes without invoking a chemical composition change on the water. 

Moreover, the two procedures display different and complementary properties so that each of them is the method of choice to obtain specific information on the 2D separations. The SMO procedure is an unique tool to quantitatively estimate the degree of peak overlapping present in a map as well as to predict the influence of different experimental conditions on peak overlapping. The strength of the 2D autocovariance function method lies in its ability to simply single out ordered retention pattern hidden in the complex separation, which can be related to information on the chemical composition of the complex mixture. 

An extension of the application of these maps to the systematic description of certain groups of ternary alloys has been presented also by Pettifor (1988a, b). Composition averaged Mendeleev numbers can be used, for instance, in the description of pseudo-binary, ternary or quaternary alloys. All these maps show well-defined domains of structural stability for a given stoichiometry, thus making the search easier for new ternary or quaternary alloys with a particular structure type (and which, as a consequence, may have the potential of interesting properties and applications (Pettifor 1988a, b)). 

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