23 research outputs found
Le risque accru de légiférer par référence en droit pénal:un exemple récent en matière d'écoutes téléphoniques
Le risque accru de légiférer par référence en droit pénal:un exemple récent en matière d'écoutes téléphoniques
Le risque accru de légiférer par référence en droit pénal:un exemple récent en matière d'écoutes téléphoniques
Catalytic Reactions on Crystallites: Imaging and in situ Chemical Probing at the Nanometer Scale
Progress in the kinetics and mechanisms of chemical reactions at the atomic and molecular levels. Thematic issue honouring Francois Garin Foreword
International audienceno abstrac
Superior Fischer-Tropsch performance of uniform cobalt nanoparticles deposited into mesoporous SiC
International audienc
Nanometric chemical clocks
Field ion microscopy combined with video techniques and chemical probing reveals the existence of catalytic oscillatory patterns at the nanoscale. This is the case when a rhodium nanosized crystal-conditioned as a field emitter tip-is exposed to hydrogen and oxygen. Here, we show that these nonequilibrium oscillatory patterns find their origin in the different catalytic properties of all of the nanofacets that are simultaneously exposed at the tip's surface. These results suggest that the underlying surface anisotropy, rather than a standard reaction-diffusion mechanism, plays a major role in determining the self-organizational behavior of multifaceted nanostructured surfaces. Surprisingly, this nanoreactor, composed of the tip crystal and a constant molecular flow of reactants, is large enough for the emergence of regular oscillations from the molecular fluctuations. © 2009 by The National Academy of Sciences of the USA.Journal Articleinfo:eu-repo/semantics/publishe