Bifunctionalized poly(amidoamine) dendrimers having both quaternary ammonium groups and primary amines on their periphery were prepared. Pd and Pt nanoparticles were encapsulated within these dendrimers by extraction of the metal ions into their interior, followed by chemical reduction. The high positive charge on the surface of these dendrimers reduces the likelihood of agglomeration, and the unquaternized amine groups provide a reactive handle for immobilizing the dendrimer-encapsulated nanoparticles (DENs) onto surfaces. High-resolution transmission electron microscopy images reveal that both encapsulated Pd and Pt nanoparticles are nearly monodisperse with an average diameter of 1.7 ( 0.3 nm. Pd and Pt DENs were immobilized onto Au surfaces using an intermediary self-assembled monolayer as an adhesion layer. Only a small fraction of the resulting nanoparticle monolayer is lost when sonicated in an acidic aqueous solution or subjected to electrochemical cycling.

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A general approach for functional group confinement is demonstrated for primary amines and relies on the formation of a pocket in the shape of an inverted wedge at the interface between grafted monosubstituted calix-[4]-arenes and silica surface. Shape-selective binding of salicylaldehyde to the confined amine materials is demonstrated.

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In the paper, reactorless high efficiency boost DC/DC converter for EV is proposed. In proposed converter, improves efficiency because decrease power loss when the switches are turned on/off using zero current switching (ZCS) at all switch of primary full bridge. By replacing reactance ingredients of L-C resonance circuit for ZCS with leakage inductance ingredients of high frequency transformer, it reduces system size and expense because of not add special reactor. For validity verification of proposed converter, in the paper implements simulation using PSIM and perform experiment by making 5KW DC/DC converter. In experimental results, efficiency of proposed converter conformed superiority.