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We propose a simple theoretical calculation scheme based on the phenomenological Fourier heat-flow formalism to study thermal transport behaviors in nanoscale copper rods. The axial heat transport is characterized by a new super-oscillatory feature along with small-amplitude heat spikes. It is anticipated that these atypical spikes are generated by accumulation of localized 'hotspots' that have low heat dissipation characteristics. In the case of radial transport, we witness the existence of three distinct heat regimes owing to buildup of hot electrons after experiencing ballistic scattering events. It is important to note that, even though the nanorod diameter is comparable to or smaller than the electron mean free path length, [λ.sub.mfp] ~ 30 nm; multiple ballistic electronic scattering from the outer surface of the nanorods and subsequent accrual into several layers through secondary collisional events has led to concentric heat zones. The hotspots disappear when the nanorod diameter exceeds [λ.sub.mfp]. Key words: nanorod, metallic system, thermal transport, hotspot. Nous proposons un schema de calcul theorique base sur le formalisme de transfert de chaleur de Fourier, afin d'etudier le comportement du transport dans des nano-tiges de cuivre. Le transport axial est caracterise par une nouvelle super- oscillation avec de petits pics de chaleur de faible amplitude. Nous pensons que ces pics atypiques sont generes par l'accumulation locale de points chauds caracterises par une faible dissipation thermique. Dans le cas du transport radial, nous observons l'existence de trois regimes de chaleur distincts dus a l'accumulation d'electrons chauds suivant leur diffusion balistique. Il est un fait important, meme si le diametre de la nano-tige est comparable ou plus petit que le libre parcours moyen de l'electron, [λ.sub.mfp] ~ 30 nm: une diffusion electronique balistique multiple de la surface exterieure de la nano-tige et l'accumulation subsequente dans plusieurs couches via des collisions secondaires, menent a des zones de chaleur concentriques. Les points chauds disparaissent lorsque le diametre depasse [λ.sub.mfp]. [Traduit par la Redaction] Mots-cles: nano-tige, systeme metallique, transport thermique, point chaud., 1. Introduction In recent years, thermal properties of low-dimensional systems have gathered immense interest because of fundamental concern and relevance in diverse areas of nanotechnology research [1, 2]. An abrupt [...]

The nanoporous Ti[O.sub.2] network sensitized by ZnS nanospheres is produced and described as an idealized scheme to facilitate interfacial charge transfer effects. The findings suggest that when a large band gap material is restricted in a confined geometry of lower energy band gap then the surface states are mainly responsible in the charge transport phenomena.

Several studies are conducted to analyze the fabrication and the properties of the europium doped zinc oxide nanoparticles, nanorods and urchins. The structures are shown to exhibit highly dominant defect related emissions, as compared to the near band edge emission.

The synthesis of ZnO quantum particles is reported by using a quenching method. The possible reason for the variations that were encountered is argued to be an effective-mass approximation model, which fits well for small effective mass and high-dielectric constant (epsilon(sub 0)).