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941.
Derrick M Fernandez E Fries R Hyman L Kooijman P Loos JS Musgrave B Price LE Schlereth J Sugano K Weiss JM Wood DE Baranko G Baringer P Blockus D Brabson B Forden GE Gray SW Jung C Neal H Ogren H Rust DR Valdata-Nappi M Akerlof C Bonvicini G Chapman J Errede D Harnew N Kesten P Kooijman S Meyer DI Nitz D Rubin D Seidl AA Thun R Trinko T Willutzky M Beltrami I Bylsma BG DeBonte R Koltick D Gan KK Loeffler FJ Low EH Mallik U McIlwain RL Miller DH Ng CR Ong PP Rangan LK Shibata EI Wilson aR Cork B 《Physical review letters》1985,54(24):2568-2571
942.
In situ time-resolved Fourier transform infrared (FTIR) and microprobe Raman spectroscopies were used to characterize the reaction mechanisms of the partial oxidation of methane to syngas over SiO(2)- and gamma-Al(2)O(3)-supported rhodium and ruthenium catalysts. The interaction of both pure methane and a methane/oxygen mixture at a stoichiometric feed ratio with an oxygen-rich catalyst surface led to the formation of CO2 and H(2)O as the primary products. For the H(2)-pretreated samples, the reaction mechanisms with the catalysts differ. Only Rh/SiO(2) is capable of catalyzing the direct oxidation of methane to syngas, while syngas formation over Rh/gamma-Al(2)O(3), Ru/SiO(2), and Ru/gamma-Al(2)O(3) can be achieved mainly via a combustion-reforming scheme. The significant difference in the mechanisms for partial oxidation of methane to syngas over the catalysts can be correlated to the differences in the concentration of oxygen species (O(2-)) on the catalyst surface during the reaction, mainly due to the difference in the nature of the metals and supports. 相似文献
943.
Tinghua Wu Dongmin Lin Ying Wu Xiaoping Zhou Qiangu Yan Weizheng Weng Huilin Wan 《天然气化学杂志》2007,16(3):316-321
Partial oxidation of methane to syngas (POM) over Rh/SiO2 catalyst was investigated using in-situ FT-IR. When methane interacted with 1.0wt%Rh/SiO2 catalyst, it was dissociated to adsorbed hydrogen and CHx species. The adsorbed hydrogen atoms were transferred to SiO2 surface by "spill-over" and reacted with lattice oxygen to form surface -OH species. POM mechanism was investigated over Rh/SiO2 catalyst using in-situ FT-IR. It was found that CO2 was formed before CO could be detected when CH4 and O2 were introduced over the preoxidized Rh/SiO2 catalyst, whereas CO was detected before CO2 was formed over the prereduced Rh/SiO2 catalyst. 相似文献
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Zhu Qing Wu Haijun Wang Fang He Anqi Huang Kun Wei Yongju Liu Cuige Zhai Yanjun Weng Shifu Yang Zhanlan Xu Yizhuang Noda Isao Wu Jinguang 《平面色谱法杂志一现代薄层色谱法》2014,27(2):80-83
JPC – Journal of Planar Chromatography – Modern TLC - While in situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures, the conventional stationary phase,... 相似文献
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947.
Xiaojun Zeng Dr. Junling Li Dr. Chin K. Ng Dr. Gerald B. Hammond Dr. Bo Xu 《Angewandte Chemie (International ed. in English)》2018,57(11):2924-2928
We have developed a widely applicable nucleophilic (radio)fluoroclick reaction of ynamides with readily available and easy‐to‐handle KF(18F). The reactions exhibited high functional‐group tolerance and needed only an ambient atmosphere. This 18F addition to C?C unsaturated bonds proceeded with extraordinarily high radiochemical yields. 相似文献
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950.
Prof. Dr. Sunney I. Chan Yu‐Jhang Lu Dr. Penumaka Nagababu Dr. Suman Maji Mu‐Cheng Hung Marianne M. Lee Prof. Dr. I‐Jui Hsu Pham Dinh Minh Jeff C.‐H. Lai Kok Yoah Ng Sridevi Ramalingam Prof. Dr. Steve S.‐F. Yu Prof. Dr. Michael K. Chan 《Angewandte Chemie (International ed. in English)》2013,52(13):3731-3735