Surface decoupling transitions

Top substrate-fixed middle racemization transition bot-surface-decoupling transition. 

Large numbers of functionalized LB films have been prepared. Highly ordered LB films have been formed by the inclusion of surface-active cobaltous phthalocyanine [168] amphiphilic TCNQ was assembled to function as conducting LB films [169] liquid-crystalline LB films, potentially capable of undergoing thermotropic or lyotropic phase transitions [170, 171], have also been generated. Spacer groups introduced into polymeric surfactants (23) helped to stabilize the LB films which they formed by decoupling the motion of pendant polymers (see Fig. 13) [172]. 

When considering the roles of promoters in vanadium phosphate catalysts, care must be taken to decouple the effects of structural promotion which increases the surface area, and hence the activity of catalysts. A vast array of transition metals, alkali metals, alkali earth metals, and lanthanides have all been studied as promoters but only a handful have been found to have promotional effects that are independent of the surface area of the catalyst. 

The reduction on aqueous transition metal species at the surfaces of Fe(II)-containing oxides is defined in terms of heterogeneous redox reactions that occur concurrently with oxidation and weathering of the mineral surfaces. Electrochemical measurements made on mineral electrodes document that such reactions are coupled half cells in which reductive dissolution can be decoupled and substituted for reduction of aqueous species. This is confirmed experimentally in aqueous/mineral suspensions in which Cr(VI), V(V) Fe(III) and Cu(II) are reduced to lower valance states. 

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