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Carbon‐Supported Copper Nanomaterials: Recyclable Catalysts for Huisgen [3+2] Cycloaddition Reactions 下载免费PDF全文
Diana Döhler Dr. Franz Jirsa Dr. Annette Meister Prof. Dr. Liberata Guadagno Eik Koslowski Prof. Dr. Michael Bron Prof. Dr. Wolfgang H. Binder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10763-10770
Highly disperse copper nanoparticles immobilized on carbon nanomaterials (CNMs; graphene/carbon nanotubes) were prepared and used as a recyclable and reusable catalyst to achieve CuI‐catalyzed [3+2] cycloaddition click chemistry. Carbon nanomaterials with immobilized N‐heterocyclic carbene (NHC)‐Cu complexes prepared from an imidazolium‐based carbene and CuI show excellent stability including high efficiency at low catalyst loading. The catalytic performance evaluated in solution and in bulk shows that both types of Cu‐CNMs can function as an effective recyclable catalysts (more than 10 cycles) for click reactions without decomposition and the use of external additives. 相似文献
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Tharamani C. Nagaiah Shankhamala Kundu Michael Bron Martin Muhler Wolfgang Schuhmann 《Electrochemistry communications》2010,12(3):338-341
A new approach to synthesize nitrogen-doped carbon nanotubes (NCNTs) as catalysts for oxygen reduction by treating oxidized CNTs with ammonia is presented. The surface properties and oxygen reduction activities were characterized by cyclic voltammetry, rotating disk electrode and X-ray photoelectron spectroscopy. NCNTs treated at 800 °C show improved electrocatalytic activity for oxygen reduction as compared with commercially available Pt/C catalysts. 相似文献
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Imaging metallic multilayer structures through ultrafast optically driven excited electron transport
Received: 20 September 1998 / Revised version: 21 December 1998 相似文献
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D.P. Barber U. Becker G. Berghogff A. Böhm J.G. Branson J. Bron D. Buikman J.D. Burger C.C. Chang H.S. Chen M. Chen C.P. Cheng Y.S. Chu R. Clare P. Duinker G.Y. Fang H. Fesefeldt D. Fong R.Y. Zhu 《Physics letters. [Part B]》1980,95(1):149-153
By combining results from the MARK-J at PETRA on Bhabha scattering, μ+μ- and τ+τ- production with recent world data from neutrino-electron scattering experiments, we determine unique values for the leptonic weak neutral current coupling constants gV and gA in the framework of electroweak models containing a single Z0. In contrast to previous analyses, we only use data from purely leptonic interactions, and therefore avoid the inherent uncertainties resulting from the use of hadronic targets. From the MARK-J data alone in the context of the standard SU(2) ? U (1) model of Glashow, Weinberg and Salam, we find sin2θW=0.24±0.11. 相似文献
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D.P. Barber U. Becker H. Benda A. Boehm J.G. Branson J. Bron D. Buikman J. Burger C.C. Chang H.S. Chen M. Chen C.P. Cheng Y.S. Chu R. Clare P. Duinker G.Y. Fang H. Fesefeldt D. Fong R.Y. Zhu 《Physics letters. [Part B]》1979,85(4):463-466
We report on the results of the study of e+e? collisions at the highest PETRA energy of √s = 31.57 GeV, using the 4π sr, electromagnetic and calorimetric detector Mark J. Based on 88 hadron events, and an integrated luminosity of 243 nb?1 we obtain R = σ(e+e? → hadrons)/σ(e+e? → μ+μ?) = 4.0 ± 0.5 (statistical) ± 6 (systematic). The R value, the measured thrust distribution and average spherocity show no evidence for the production of new quark flavors. 相似文献
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Aluminum - epoxy single lap joints were subjected at different temperatures to torsional vibrations at constant amplitude superimposed on a creep load. This combination of dynamic and static stresses was chosen in order to simulate to a certain extent the real service conditions of an ordinary bonded joint. The shear strength of these joints was checked in tension at room temperature after their removal from the special device in which the superimposed stresses were applied. It was found that the shear strength of the joint is very dependent on its thermo-mechanical history. DSC analyses and SEM micrographs of the failure surface were used in an attempt to find some correlation between the mechanical properties and the microstructure of the adhesive. 相似文献