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941.
Roland Coratger Bastien Calmettes Youness Benjalal Xavier Bouju Christophe Coudret 《Surface science》2012,606(3-4):444-449
The electronic and structural properties of large molecules composed of a central hexa-phenylbenzene core surrounded by six adamantyl groups (Ad6HPB) adsorbed on Ag(111) have been investigated using low temperature scanning tunneling microscopy (STM), adsorption and image calculations. On large 2D domains, the molecular organization displays two lattices. In one of them, molecules are slightly nested as a result of their relative flexibility during packing. These compounds also exhibit contrast variations in terms of used bias voltage in the self-assembled domains as well as in single molecule observations. This is attributed to the peculiar electronic properties of Ad6HPB and to the role of peripheral groups. 相似文献
942.
943.
944.
Romain Sallio Stéphane Lebrun Francine Agbossou-Niedercorn Christophe Michon Eric Deniau 《Tetrahedron: Asymmetry》2012,23(13):998-1004
Two alternative synthetic approaches to a variety of enantioenriched 6-arylated piperidin-2-ones have been developed. The first one is based on the hydrogenation of suitably arylated chiral cyclic enehydrazides. The second approach relies on the asymmetric catalytic hydrogenation of the corresponding N-alkylated precursors. 相似文献
945.
946.
Christophe Finot Julien Fatome Stéphane Pitois Guy Millot Erwan Pincemin 《Optical Review》2011,18(3):257-263
In this contribution, we numerically and experimentally investigate the extension of the so-called Mamyshev regenerator with
the implementation of an additional Raman gain. We evaluate the potential efficiency and advantages of this new active Mamyshev
regenerator at 40 Gbps and we highlight a strong reduction of the working power as well as a large improvement of the available
output power. 相似文献
947.
Ibrahim A. Amar Rong Lan Christophe T. G. Petit Shanwen Tao 《Journal of Solid State Electrochemistry》2011,15(9):1845-1860
Ammonia is one of the most produced chemicals worldwide, and it is not only a major end product but also an important energy
storage intermediate. The solid-state electrochemical synthesis of ammonia has the promise to overcome the limitations of
the conventional catalytic reactors such as the limited conversion, severe environmental pollution and high energy consumption.
Solid-state electrolytes either protonic or oxide ion conductors have been reviewed and particular emphasis is placed on their
application to synthesise ammonia. The highest rate of ammonia formation according to the type of electrolyte utilised were
in the following order; solid polymers > Ce0.8Gd0.2O2−δ-(Ca3(PO4)2-K3PO4) composites > fluorites > perovskites > pyrochlores although the catalysts in electrodes also play an important role. The
highest rate reported so far is found to be 1.13 × 10−8 mol s−1 cm−2 at 80 °C with a potential of 2 V using Nafion membrane, SmFe0.7Cu0.1Ni0.2O3 (SFCN), and Ni-Ce0.8Sm0.2O2−δ as solid electrolyte, cathode and anode, respectively. Synthesising ammonia from steam and N2, by-passing H2 stage offers many advantages such as reduction of device numbers and then the overall costs. The factors affecting the rate
of ammonia formation have been discussed as well. 相似文献
948.
Serpil Demir Yasemin Gökçe Nazan Kaloğlu Jean‐Baptiste Sortais Christophe Darcel İsmail Özdemir 《应用有机金属化学》2013,27(8):459-464
A series of new piano‐stool iron(II) complexes comprising N‐heterocyclic carbene ligands [Fe(Cp)(CO)2(NHC)]I (NHC = 1,3‐disubstituted imidazolidin‐2‐ylidene) have been synthesized and analyzed by 1H NMR, 13C NMR, IR, elemental analysis and mass spectrometric techniques. These compounds were easily prepared from the reaction of disubstituted imidazolidin‐2‐ylidene with [FeI(Cp)(CO)2] in toluene at room temperature. These complexes were tested in the catalytic hydrosilylation reaction of aldehydes and ketones with phenylsilane in solvent‐free conditions. After a basic hydrolysis step, the corresponding alcohols were obtained in good yields. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
949.
Dr. Uttam Chakraborty Dr. Serhiy Demeshko Prof. Dr. Franc Meyer M. Sc. Christophe Rebreyend Prof. Dr. Bas de Bruin Prof. Dr. Mihail Atanasov Prof. Dr. Frank Neese Dr. Bernd Mühldorf Prof. Dr. Robert Wolf 《Angewandte Chemie (International ed. in English)》2017,56(27):7995-7999
The 15 valence-electron iron(I) complex [CpArFe(IiPr2Me2)] ( 1 , CpAr=C5(C6H4-4-Et)5; IiPr2Me2=1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidene) was synthesized in high yield from the FeII precursor [CpArFe(μ-Br)]2. 57Fe Mössbauer and EPR spectroscopic data, magnetic measurements, and ab initio ligand-field calculations indicate an S= 3/2 ground state with a large negative zero-field splitting. As a consequence, 1 features magnetic anisotropy with an effective spin-reversal barrier of Ueff=64 cm−1. Moreover, 1 catalyzes the dehydrogenation of N,N-dimethylamine–borane, affording tetramethyl-1,3-diaza-2,4-diboretane under mild conditions. 相似文献
950.