Synthesis of gold ring-shape nanoparticles using co-sputtering over liquids

Abstract The energy flow, dE/dη, is studied at large pseudorapidities in proton-proton collisions at the LHC, for centre-of-mass energies of 0.9 and 7 TeV. The measurements are made using the CMS detector in the pseudorapidity range 3.15 < |η| < 4.9, for both minimum-bias events and events with at least two high-momentum jets. The data are compared to various pp Monte Carlo event generators whose theoretical models and input parameter values are sensitive to the energy-flow measurements. Inclusion of multiple-parton interactions in the Monte Carlo event generators is found to improve the description of the energy-flow measurements

Star formation triggered by non-head-on cloud-cloud collisions, and clouds with pre-collision sub-structure

In an earlier paper, we used smoothed particle hydrodynamics (SPH) simulations to explore star formation triggered by head-on collisions between uniform-density 500 M clouds, and showed that there is a critical collision velocity, vCRIT. At collision velocities below vCRIT, a hub-and-spoke mode operates and delivers a monolithic cluster with a broad mass function, including massive stars (M 10 M) formed by competitive accretion. At collision velocities above vCRIT, a spider’s-web mode operates and delivers a loose distribution of small sub-clusters with a relatively narrow mass function and no massive stars. Here we show that,if the head-on assumption is relaxed, vCRIT is reduced. However, if the uniform-density assumption is also relaxed, the collision velocity becomes somewhat less critical: a low collision velocity is still needed to produce a global hub-and-spoke system and a monolithic cluster, but, even at high velocities, large cores – capable of supporting competitive accretion and thereby producing massive stars – can be produced. We conclude that cloud–cloud collisions may be a viable mechanism for forming massive stars – and we show that this might even be the major channel for forming massive stars in the Galaxy

Co-sputtering of gold and copper onto liquids: a route towards the production of porous gold nanoparticles

peer reviewe

Co-sputtering of gold and copper onto liquids: a route towards the production of porous gold nanoparticles

peer reviewe

Direct nanopatterning of polymer/silver nanoblocks under low energy electron beam irradiation

International audienc

The Kirkendall effect and nanoscience: hollow nanospheres and nanotubes

Hollow nanostructures are ranked among the top materials for applications in various modern technological areas including energy storage devices, catalyst, optics and sensors. The last years have witnessed increasing interest in the Kirkendall effect as a versatile route to fabricate hollow nanostructures with different shapes, compositions and functionalities. Although the conversion chemistry of nanostructures from solid to hollow has reached a very advanced maturity, there is still much to be discovered and learned on this effect. Here, the recent progress on the use of the Kirkendall effect to synthesize hollow nanospheres and nanotubes is reviewed with a special emphasis on the fundamental mechanisms occurring during such a conversion process. The discussion includes the oxidation of metal nanostructures (i.e., nanospheres and nanowires), which is an important process involving the Kirkendall effect. For nanospheres, the symmetrical and the asymmetrical mechanisms are both reviewed and compared on the basis of recent reports in the literature. For nanotubes, in addition to a summary of the conversion processes, the unusual effects observed in some particular cases (e.g., formation of segmented or bamboo-like nanotubes) are summarized and discussed. Finally, we conclude with a summary, where the prospective future direction of this research field is discussed

Interface Engineering in CuInSe 2 Solar Cells Using Ammonium Sulfide Vapors

International audienc

Sponge-like carbon thin films: The dealloying concept applied to copper/carbon nanocomposite

International audienc

Impact of the morphology and composition on the dealloying process of co-sputtered silver-aluminum alloy thin films

International audienc