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Inkjet printed patterns using copper nanoparticles (NPs) were sintered at 250 °C under reducing atmosphere. The size of NPs covered by organic capping molecules was 5 nm on average. A crack-free Cu film was obtained after sintering. The grain size of the film reached 500 nm upon grain growth. However, only agglomeration of NPs was observed at the bottom of the film. The resistance was 0.88 Ω on average and the patterns were electrically tested by light-emitting diodes.

Although multicomponent core-shell type nanomaterials are one of the highly desired structural motifs due to their simultaneous multifunctionalities, the fabrication strategy for such nanostructures is still in a primitive stage. Here, we present a redox-transmetalation process that is effective as a general protocol for the fabrication of high quality and well-defined core-shell type bimetallic nanoparticles on the sub-10 nm scale. Various core-shell type nanomaterials including Co@Au, Co@Pd, Co@Pt, and Co@Cu nanoparticles are fabricated via transmetalation reactions. Compared to conventional sequential reduction strategies, this transmetalation process has several advantages for the fabrication of core-shell type nanoparticles: (i) no additional reducing agent is needed and (ii) spontaneous shell layer deposition occurs on top of the core nanoparticle surface and thus prevents self-nucleation of secondarily added metals. We also demonstrate the versatility of these core-shell structures by transferring Co@Au nanoparticles from an organic phase to an aqueous phase via a surface modification process. The nanostructures, magnetic properties, and reaction byproducts of these core-shell nanoparticles are spectroscopically characterized and identified, in part, to confirm the chemical process that promotes the core-shell structure formation.

The authors report on a study of the transformation behavior in Ti-15-3 and Ti{sub 3}Al-Nb alloys especially on the nature of the premartensitic phenomena by electron diffraction and microscopy. The premartensitic behavior of commercial beta Ti alloys has not been reported in other papers. The microstructure of premartensitic phase, called tweed or mottled structure composed of fine streak lamella, may have significant effect on mechanical properties of hardness, strength and toughness, since the structure of the phase provides many sites of nuclear in aging. The authors will consider the aging behavior of {beta} or B2 Ti alloys caused by fine precipitates from premartensitic phase, and the phase relationship between precipitates and matrix.

Co@Pt nanoparticles as a bifunctional nanoplatform system for the hydrogenation of various unsaturated organic molecules under mild conditions and also for magnetic separation and recycling are demonstrated.

Massive fabrication of free-standing Co/Pt magnetic barcode nanowires with well-defined interfaces and layer thicknesses is obtained after freeing them from porous templates. Such barcodes display bamboo-like shapes with identical motifs either inside or out of the templates. The ferromagnetism of these barcode nanowires can be modulated easily depending on the cobalt segments and shape anisotropies. Further enhancements of the ferromagnetism of Co/Pt barcodes are also accomplished through interfacial alloying processes via a thermally induced phase transition.