Interfacial proximity effect

Nanocarbon hybrids have recently been introduced as a new class of multifunctional composite materials [18]. In these hybrids, the nanocarbon is coated by a polymer or by the inorganic material in the form of a thin amorphous, polycrystalline or single-crystalline film. The close proximity and similar size domain/volume fraction of the two phases within a nanocarbon hybrid introduce the interface as a powerful new parameter. Interfacial processes such as charge and energy transfer create synergistic effects that improve the properties of the individual components and even create new properties [19]. We recently developed a simple dry wrapping method to fabricate a special class of nanocarbon hybrid, W03 /carbon nanotube (CNT) coaxial cable structure (Fig. 17.2), in which W03 layers act as an electrochromic component while aligned... 

Probably far more important than the partitioning behavior is the fact that lipid oxidation in emulsions is site specific—i.e., most of the radicals are actually formed at or near the membrane. A close proximity to the interface is required to catalyze the reaction (Asua et al., 1989). Studies have shown that it is primarily the interfacial/subsurface concentration of transition metals that controls the rate of the reaction, while the concentration of transition metals in the bulk phase is secondary. This insight also provides a means to reduce the rate of the reaction. Experiments using a number of different antioxidants have in fact proven that lipid oxidation is most effectively inhibited if surface-active antioxidants are added. Antioxidants that are able to accumulate at the interface are closer to the site of lipid oxidation initiation and are therefore more efficient (Frankel et al., 1996). 

We conclude that the proximal radial distribution function (Fig. 1.11) provides an effective deblurring of this interfacial profile (Fig. 1.9), and the deblurred structure is similar to that structure known from small molecule hydration results. The subtle differences of the ( ) for carbon-(water)hydrogen exhibited in Fig. 1.11 suggest how the thermodynamic properties of this interface, fully addressed, can differ from those obtained by simple analogy from a small molecular solute like methane such distinctions should be kept in mind together to form a correct physical understanding of these systems. 

When nonpolar compounds are suspended in water their relative insolubility causes them to associate, diminishing the water-hydrocarbon interfacial area (a hydrophobic effect). This association is greater in water than in methanol and brings the reactive partners into close proximity, increasing the rate of reaction. Any additive that increases the hydrophobic effect will increase the rate. ... 

Mohapatra SR, Thakur AK, Choudhary RNP (2009) Effect of nanoscopic confinement on improvement in ion conduction and stability properties of an intercalated polymer nanocomposite electrolyte for energy storage applications. J Power Sources 191 601-613 Napolitano S, Cangialosi D (2013) Interfacial free volume and vitrification rednctiai in Tg in proximity of an adsorbing interface explained by the free volume holes diffusitm model. Macromolecules 46 8051-8053... 

Low-Dielectric Interfaces— The presence of a low-dielectric material beneath the adsorbing boundary has considerable implications for adsorption. In particular, in the proximity of such an interface the polyelectrolyte experiences a repulsive force from the image charges that effectively displace the polymer from the interfacial region of a high attractive potential. This image repulsion grows... 

The classical view of the deviation from bulk behavior focuses on the balance of finite size effects and interfacial interactions in systems at thermodynamic equilibrium. For example, thin films (thickness typically below 100 nm) are treated as slabs where the bulk molecular dynamics is locally perturbed by the presence of free surfaces ( 2 nm layer at the interface with air, other gases, or vacuum) and adsorbing interfaces (proximity of non-repulsive wall). A reduction in the glass transition temperature is commonly imputed to the faster dynamics of free smfaces, while the presence of an adsorbing interface is considered as a somce of slower molecular modes. 

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