Minor Image model

The surest test for chirality is a careful examination of minor-image forms for superimposability. Working with models provides the best practice in dealing with molecules as three-dimensional objects and is strongly recommended. 

Recent work has supported early observations (e.g. Aggarwal 1976 Hashimoto et al. 1983) of a liquid micellar phase between the BCC micelle phase and the disordered phase. A representative TEM image from a spherical micellar liquid phase is shown in Fig. 2.18. Kinning and Thomas (1984) analysed SANS data obtained by Berney et al. (1982) on PS-PB diblocks and PS/PS-PB blends where the minority (PB) component formed spherical micelles with only liquid-like ordering. The Percus-Yevick model for liquids of hard spheres was used to obtain the interparticle contribution to the scattered intensity (Kinning and Thomas 1984). The ordering of an asymmetric PS-PI diblock was observed by Harkless... 

The methyl substituted spiro system JO (Fig. 3) was also studied (24, 25). With this system, two isomers JJ and J2 are possible and molecular models show that they can each exist in four different conformations. Evaluation of the anomeric and the steric effects of each conformation leads to the prediction that isomer JJ exists in the conformation 11A only (0 kcal/mol relative to the other conformations) whereas isomer 12 is a mixture of a major (12A, 2.4 kcal/mol) and a minor (12B, 2.9 kcal/mol) conformer. However, since isomers JJ and J2 are interconvertible (JJ can be converted into the mirror image of J2 by opening and reclosure of the acetal function) and... 

Section 6.2 shows how they are placed within the model equations. Based on the assumptions for these models it follows that all plant effects as well as axial dispersion, void fraction and mass transfer resistance are independent of the adsorption/ desorption within the column. Modeling always results in a virtual image of the real world, i.e. in reality the parameters might be influenced by adsorption, but with a reliable model this is of minor importance. 

Figure 1 compares experimental data for G and with the predictions of the emulsion model for a 90/10 (mass %) PMMA/PS at 200 C. For this blend, the viscosity of the minor component is considerably smaller than that of the major component, q(ps)I q pmma) 0-035. The morphology was characterized by transmission electronic microscopy (TEM) and the average particle radius was estimated by digital image analysis to be around 0.22 im. The interfacial tension has been taken as 1.5 mN/m [4]. It should be mentioned that the morphology of the blend was found to be the same before and after the rheological experiments carried out at 200 C for about 2 h. 

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