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991.
Filip Novak Nicolas Plumeré Bernd Schetter Bernd Speiser Diana Straub Hermann A. Mayer Michaela Reginek Klaus Albert Gerd Fischer Christoph Meyer Hans-Joachim Egelhaaf Børre Børresen 《Journal of Solid State Electrochemistry》2010,14(2):289-303
Stöber silica nanoparticles with a diameter of approximately 800 nm are covalently modified by redox-active ferrocene or (diamine)(diphosphine) ruthenium(II) units attached to a spacer. The particles are characterized by NMR spectroscopic and chemical techniques. Two variants of modification by condensation are compared. Besides an estimation of the size and the particle porosity, the agglomeration behavior in solvents of different polarity is investigated. The adsorption of the particles to an electrode surface is followed. 相似文献
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Gerd Herzog 《Numerical Functional Analysis & Optimization》2017,38(8):1008-1013
It is known that vector translations are contractive with respect to Thompson’s part metric. Here, we give a simple proof, based on a representation of Thompson’s metric through positive functionals. Moreover, we use contractivity of translations to prove a fixed point result for mappings that are Lipschitz continuous with respect to Thompson’s metric with Lipschitz constant r>1. The case r = 1 for order preserving or order reversing mappings has been recently studied by Lawson and Lim. We apply our result to a nonlinear boundary value problem. 相似文献
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Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine‐Carboxyl‐Linked Immobilized Dirhodium Catalyst
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Torsten Gutmann Jiquan Liu Niels Rothermel Yeping Xu Eva Jaumann Mayke Werner Hergen Breitzke Snorri T. Sigurdsson Gerd Buntkowsky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3798-3805
A novel heterogeneous dirhodium catalyst has been synthesized. This stable catalyst is constructed from dirhodium acetate dimer (Rh2(OAc)4) units, which are covalently linked to amine‐ and carboxyl‐bifunctionalized mesoporous silica (SBA‐15?NH2?COOH). It shows good efficiency in catalyzing the cyclopropanation reaction of styrene and ethyl diazoacetate (EDA) forming cis‐ and trans‐1‐ethoxycarbonyl‐2‐phenylcyclopropane. To characterize the structure of this catalyst and to confirm the successful immobilization, heteronuclear solid‐state NMR experiments have been performed. The high application potential of dynamic nuclear polarization (DNP) NMR for the analysis of binding sites in this novel catalyst is demonstrated. Signal‐enhanced 13C CP MAS and 15N CP MAS techniques have been employed to detect different carboxyl and amine binding sites in natural abundance on a fast time scale. The interpretation of the experimental chemical shift values for different binding sites has been corroborated by quantum chemical calculations on dirhodium model complexes. 相似文献
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Isabel Rauscher Benjamin Bender Gerd Grözinger Oliver Luz Rolf Pohmann Michael Erb Fritz Schick Petros Martirosian 《Magnetic resonance imaging》2014