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51.
Yumeng Xi Boliang Dong Edward J. McClain Qiaoyi Wang Tesia L. Gregg Novruz G. Akhmedov Jeffrey L. Petersen Xiaodong Shi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(18):4745-4749
A general method for the synthesis of α‐substituted vinyl sulfones makes use of a combination of a triazole gold complex and gallium triflate. This efficient C S bond formation between simple terminal alkynes and sulfinic acids provides access to various α‐substituted vinyl sulfones. 相似文献
52.
Preparation and characterization of Al2O3-MgO mixed oxides 总被引:1,自引:0,他引:1
A new catalyst system V-Cs-Cu-Tl/TiO2·SiC for vapor-phase selective oxidation reaction of p-tert-butyltoluene to p-tert-butylbenzaldehyde were studied. It was found that the addition of thallium promoted the reaction. After 365 hours stability test, the V-Cs-Cu-Tl/TiO2·SiC catalyst still kept excellent result that conversion of p-tert-butyltoluene and the selectivity of p-tert-butylbenzaldehyde reach 10 mol% and 80 mol%. The catalyst was characterized by XRD, TEM, FT-IR and ICP measurements. 相似文献
53.
Gold‐Catalyzed Intermolecular CS Bond Formation: Efficient Synthesis of α‐Substituted Vinyl Sulfones 下载免费PDF全文
Yumeng Xi Boliang Dong Edward J. McClain Qiaoyi Wang Tesia L. Gregg Dr. Novruz G. Akhmedov Prof. Jeffrey L. Petersen Prof. Xiaodong Shi 《Angewandte Chemie (International ed. in English)》2014,53(18):4657-4661
A general method for the synthesis of α‐substituted vinyl sulfones makes use of a combination of a triazole gold complex and gallium triflate. This efficient C? S bond formation between simple terminal alkynes and sulfinic acids provides access to various α‐substituted vinyl sulfones. 相似文献
54.
A novel bipolar conjugated polymer containing triphenylamine and 1,3,4-oxadiazole units was synthesized by Suzuki reaction.Its structure and properties were characterized by NMR,IR,UV-Vis,PL spectroscopy and electrochemical measurement. The photoluminescent spectroscopy and cyclic voltammograms measurement demonstrated that the resulting polymer shows blue emission (477 nm) and possesses both electron and hole-transporting property. 相似文献
55.
The SE1050 cascade is an open test case (QNET network) of plane turbine cascade measured at the IT ASCR wind tunnel. The two regimes with subsonic and supersonic outletMach number were selected for numerical simulation. Several numerical methods have been developed and also several turbulence models have been implemented. Comparison of computed results and experimental data gives us opportunity to discuss main features of transonic flow field in well designed turbine cascade, possibilities of its numerical capturing (grid quality, numerical viscosity, turbulence model, boundary layer transition) and its influence on prediction of energy losses. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
56.
Dr. Hao Lv Yumeng Mao Dr. Huiqin Yao Huazhong Ma Chenyu Han Prof. Yao-Yue Yang Prof. Zhen-An Qiao Prof. Ben Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(15):e202400281
The development of highly efficient electrocatalysts for complete oxidation of ethylene glycol (EG) in direct EG fuel cells is of decisive importance to hold higher energy efficiency. Despite some achievements, their progress, especially electrocatalytic selectivity to complete oxidated C1 products, is remarkably slower than expected. In this work, we developed a facile aqueous synthesis of Ir-doped CuPd single-crystalline mesoporous nanotetrahedrons (Ir-CuPd SMTs) as high-performance electrocatalyst for promoting oxidation cleavage of C−C bond in alkaline EG oxidation reaction (EGOR) electrocatalysis. The synthesis relied on precise reduction/co-nucleation and epitaxial growth of Ir, Cu and Pd precursors with cetyltrimethylammonium chloride as the mesopore-forming surfactant and extra Br− as the facet-selective agent under ambient conditions. The products featured concave nanotetrahedron morphology enclosed by well-defined (111) facets, single-crystalline and mesoporous structure radiated from the center, and uniform elemental composition without any phase separation. Ir-CuPd SMTs disclosed remarkably enhanced electrocatalytic activity and excellent stability as well as superior selectivity of C1 products for alkaline EGOR electrocatalysis. Detailed mechanism studies demonstrated that performance improvement came from structural and compositional synergies, which kinetically accelerated transports of electrons/reactants within active sites of penetrated mesopores and facilitated oxidation cleavage of high-energy-barrier C−C bond of EG for desired C1 products. More interestingly, Ir-CuPd SMTs performed well in coupled electrocatalysis of anode EGOR and cathode nitrate reduction, highlighting its high potential as bifunctional electrocatalyst in various applications. 相似文献
57.
Xue Lin Jingwei Fan Runchuan Ye Mingti Zhou Yumeng Song Dawei Lu Nanyang Xu 《Frontiers of Physics》2023,18(2):21301
The nitrogen-vacancy (NV) center in diamond has been developed as a promising platform for quantum sensing, especially for magnetic field measurements in the nano-tesla range with a nano-meter resolution. Optical spin readout performance has a direct effect on the signal-to-noise ratio (SNR) of experiments. In this work, we introduce an online optimization method to customize the laser waveform for readout. Both simulations and experiments reveal that our new scheme optimizes the optically detected magnetic resonance in NV center. The SNR of optical spin readout has been witnessed a 44.1% increase in experiments. In addition, we applied the scheme to the Rabi oscillation experiment, which shows an improvement of 46.0% in contrast and a reduction of 12.1% in mean deviation compared to traditional constant laser power SNR optimization. This scheme is promising to improve sensitivities for a wide range of NV-based applications in the future. 相似文献
58.
The aim of this paper is to show that every 2-local superderivation on an associative superalgebra
Mn(\mathbb C){M_n({\mathbb C})} is a superderivation. 相似文献
59.
L. Cassar M. Foà F. Montanari G.P. Marinelli 《Journal of organometallic chemistry》1979,173(3):335-339
The nickel-catalyzed cyanation of aromatic halides under phase-transfer conditions is reported. Both liquid—liquid and solid—liquid techniques have been used, the former giving better yields and a higher catalyst turnover. The method provides a convenient and versatile route to aromatic nitriles. 相似文献
60.