Search results for "electron"
showing 10 items of 24810 documents
Synthesis of Amino-1,2,4-triazoles by Reductive ANRORC Rearrangements of 1,2,4-Oxadiazoles
2010
The reaction of various 1,2,4-oxadiazoles with an excess of hydrazine in DMF has been investigated. 3-Amino- 1,2,4-triazoles are produced through a reductive ANRORC pathway consisting of the addition of hydrazine to the 1,2,4-oxadiazole followed by ring-opening, ring-closure, and final reduction of the 3-hydroxylamino-1,2,4-triazole intermediate. The general applicability of 1,2,4-oxadiazoles ANRORC reactivity is demonstrated also in the absence of C(5)-linked electron-withdrawing groups.
Carbon Dioxide Activation and Reaction Induced by Electron Transfer at an Oxide-Metal Interface
2015
A model system has been created to shuttle electrons through a metal-insulator-metal (MIM) structure to induce the formation of a CO2 anion radical from adsorbed gas-phase carbon dioxide that subsequently reacts to form an oxalate species. The process is completely reversible, and thus allows the elementary steps involved to be studied at the atomic level. The oxalate species at the MIM interface have been identified locally by scanning tunneling microscopy, chemically by IR spectroscopy, and their formation verified by density functional calculations.
DFT Prediction of Enhanced Reducibility of Monoclinic Zirconia upon Rhodium Deposition.
2018
Oxides are an important class of materials and are widely used, for example, as supports in heterogeneous catalysis. In a number of industrial catalytic processes, oxide supports actively participate in chemical transformations by releasing lattice oxygen anions. While this is intuitively understood for reducible oxides, the reducibility of irreducible oxides may be modified via nanoengineering or upon inclusion of foreign species. Our calculations predict that the ability of irreducible monoclinic zirconia to release oxygen improves substantially upon deposition of rhodium. Through a comprehensive screening of Rh/ZrO2 with different size of the rhodium species, we find that a Rh adatom and…
The strong coupling constant: State of the art and the decade ahead
2022
This document provides a comprehensive summary of the state-of-the-art, challenges, and prospects in the experimental and theoretical study of the strong coupling $\alpha_s$. The current status of the seven methods presently used to determine $\alpha_s$ based on: (i) lattice QCD, (ii) hadronic $\tau$ decays, (iii) deep-inelastic scattering and parton distribution functions fits, (iv) electroweak boson decays, hadronic final-states in (v) e+e-, (vi) e-p, and (vii) p-p collisions, and (viii) quarkonia decays and masses, are reviewed. Novel $\alpha_s$ determinations are discussed, as well as the averaging method used to obtain the PDG world-average value at the reference Z boson mass scale, $\…
$\Lambda_c^{\pm}$ production in pp collisions with a new fragmentation function
2020
Physical review / D D 101(11), 114021 (2020). doi:10.1103/PhysRevD.101.114021
The p-Type Doping of ZnO: Mirage or Reality?
2015
This chapter deals with a critical review on p-type doping of ZnO. In the past 15 years, ZnO has attracted considerable attention due to its unique properties, which make it a promising material for optoelectronic devices applications. However, a reliable p-type ZnO doping remains a major challenge because of self-compensation effects; thus, despite the advantages of these devices, the fabrication of ZnO-based devices is hampered by the lack of a stable p-type doping. A careful and critical analysis of the results reported in literature raises many doubts about the correctness of the doping-type assignments and, in general, the values of the electrical parameters reported. A historical surv…
Measurement of the average shape of longitudinal profiles of cosmic-ray air showers at the Pierre Auger Observatory
2019
The profile of the longitudinal development of showers produced by ultra-high energy cosmic rays carries information related to the interaction properties of the primary particles with atmospheric nuclei. In this work, we present the first measurement of the average shower profile in traversed atmospheric depth at the Pierre Auger Observatory. The shapes of profiles are well reproduced by the Gaisser-Hillas parametrization within the range studied, for E>10 17.8 eV .A detailed analysis of the systematic uncertainties is performed using ten years of data and a full detector simulation. The average shape is quantified using two variables related to the width and asymmetry of the profile, and …
Location-Awareness for Failure Management in Cellular Networks: An Integrated Approach
2021
Recent years have seen the proliferation of different techniques for outdoor and, especially, indoor positioning. Still being a field in development, localization is expected to be fully pervasive in the next few years. Although the development of such techniques is driven by the commercialization of location-based services (e.g., navigation), its application to support cellular management is considered to be a key approach for improving its resilience and performance. When different approaches have been defined for integrating location information into the failure management activities, they commonly ignore the increase in the dimensionality of the data as well as their integration into th…
Usage des organisateurs anti-entropique dans les documents électroniques : approche expérimentale des fenêtres ponctuelles
1999
International audience; Les documents électroniques permettent de nombreuses manières d'organiser, de présenter et d'accéder à l'information. Une utilisation pertinente de ces options par les auteurs requiert une bonne connaissance des effets que ces choix ont sur la représentation cognitive et les traitements faits par l'utilisateur. Cette approche des documents électroniques, sur la base du concept de représentation mentale, fournit un cadre d'analyse des structures et signaux propres à ce type d'écriture. Parmi ces signaux que nous appelons « organisateurs para-linguistiques » pour les distinguer de leurs équivalents purement textuels, un ensemble est destiné à réduire l'entropie due à l…
Paramagnetic Defects and Thermoluminescence in Irradiated Nanostructured Monoclinic Zirconium Dioxide
2022
The work was carried out under the grant of the Ministry of Education and Science of the Republic of Kazakhstan AP09260057, “Luminescence and radiation resistance of synthesized under different conditions micro- and nanostructured compacts and ceramics based on ZrO2”. The research was partly (A.I.P.) performed at the Center of Excellence of the Institute of Solid State Physics, University of Latvia, supported through European Union Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2, under grant agreement No. 739508, project CAMART2.