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Journal of Natural Gas Chemistry 2010年第6期19卷 583-588页

作者： Jian Zheng wei chu Hui Zhang Chengfa Jiang Xiaoyan Dai . Key Laboratory of Green Chemistry and Technology of Ministry of Education and Department of Chemistry Sichuan University Chengdu 610064 Sichuan China Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China Sichuan Provincial Research Institute of Safety Science and Technology Chengdu 610012 Sichuan China

The catalytic performances of Co3O4/SiO2 catalysts prepared by incipient wetness impregnation for CO oxidation were investigated using three kinds of silica as carriers with different pore sizes of 7.7,14.0 and 27.0 *** effects of calcination temperature on the catalyst surface and micro structure properties as well as catalytic performance for the oxidation of carbon monoxide were also *** catalysts were characterized by N2 adsorption-desorption,XRD,XPS,FTIR,H2-TPR and *** was found that the properties and crystal size of cobalt-containing species strongly depended on the pore size of silica *** the silica pore size increased from 7.7 to 27.0 nm,the Co3O4 crystal size increased from 8.5 to 13.5 ***,it was demonstrated that if the spinel crystal structure of Co3O4 was obtained at a calcination temperature as low as 150℃,the catalyst sample would have a high Co3O4 surface dispersion and an increase of surface active species,and thus exhibit a high activity for the oxidation of carbon monoxide.

关键词： cobalt catalysts carrier porosity catalytic property calcination temperature oxidation of carbon monoxide

Methane adsorption behavior on coal having different pore structures

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International Journal of Mining Science and Technology 2012年第6期22卷 756-760页

作者： Zhao Yi Jiang Chengfa chu wei Department of Chemical Engineering Sichuan University

The adsorption of methane onto five dry coal samples was measured at 298 K over the pressure range from 0 to 3.5 MPa using a volumetric *** isotherm data were fitted to the Langmuir and the Freundlich *** kinetic data were fitted to a pseudo second order equation,the linear driving force equation(LDF),and an intra-particle diffusion *** results showed that higher methane adsorption is correlated with larger micro-pore volumes and specific surface *** adsorption was related to the narrow micro-pore size distribution when the previous two parameters are *** kinetics study showed that the kinetics of methane adsorption onto these five dry coal samples followed a pseudo second order model very *** adsorption rates are controlled by intra-particle *** faster the intra-particle diffusion,the faster the methane adsorption rate will be.

关键词： Adsorption Coal Diffusion in solids Kinetics Pore structure

Suppression of bend loss in writing of three-dimensional optical waveguides with femtosecond laser pulses

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Science China(Physics,Mechanics & Astronomy) 2018年第7期61卷 83-86页

作者： ZhengMing Liu Yang Liao Zhi wei Fang wei chu Ya Cheng State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences School of Physical Science and Technology Shanghai Tech University State Key Laboratory of Precision Spectroscopy East Normal University Collaborative Innovation Center of Extreme Optics Shanxi University XXL – The Extreme Optoelectromechanics Laboratory East China Normal University

Optical waveguides are one of the fundamental building blocks for integrated photonic applications [ 1-6]. Recently, femtosecond laser has been used for inscribing optical wa- veguides in various transparent materials such as glass, crystals and polymers thanks to the unique capability of the locally modifying refractive index in the vicinity of the focal spot [7-11].

关键词：光波导激光损失拐弯三维脉搏透明材料聚合物

Preparation of the Supported Heteropolyacids Catalyst by Ultrasound-plasma Treatment

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 234-238页

作者： LI Yang chu wei CHEN Muhua HU Jinyan Department of Chemical Engineering Sichuan University Chengdu 610065 China Department of Environmental Engineering Sichuan University Chengdu 610065 China

Novel catalysts of phosphotungstic heteropolyacids （PW12） supported on neutral alumina were prepared by assistance of ultrasound and plasma treatment. The prepared catalysts were characterized by FT-IR pyridine adsorption （Py-IR）, temperature programmed desorption of Pyridine （Py-TPD）, BET and X-ray diffraction （XRD）, and their catalytic performances were evaluated by the cationic polymerization of tetrahydrofuran. The results indicate that plasma treatment remarkably increases the surface acidity of the prepared catalyst while ultrasonic treatment induces PW12 to uniformly disperse on the support surface and expose more active sites for the acid catalytic reaction. A higher catalytic activity （69.7%） is obtained on the novel catalyst, which significantly outstripped that on the conventional sample （57.5%）.

关键词： supported heteropolyacids ultrasound-plasma treatment acidity dispersion

Facile Synthesis of 4,5-Disubstituted 2H-1,2,3-Triazoles by Catalyst-free Cycloaddition between Substituted Vinyl Sul- fones and Sodium Azide under Ambient Conditionst

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Chinese Journal of Chemistry 2012年第12期30卷 2786-2790页

作者： Yang Jinjin Yin wei Liu Renhua chu Changhu School of Pharmacy Shanghai Key Laboratory of New Drug Design East China University of Science and Technology 130 Meilong Road Shanghai 200237 China

A highly efficient method for readily preparing 4,5-disubstituted 2H-1,2,3-triazoles was found. Under ambient conditions, a catalyst free cycloaddition between substituted vinyl sulfones and sodium azide could be completed in a very short time. In this cycloaddition process, sulfonyl group acts as a leaving group, while its ester group was retained.

关键词： vinyl sulfone sodium azide cycloaddition 1,2,3-triazole catalyst free

A DFT study of methane activation on graphite surfaces with vacancy defects

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Journal of Natural Gas Chemistry 2012年第6期21卷 708-712页

作者： Fengsi Liu wei chu Wenjing Sun Ying Xue Qian Jiang Department of Chemical Engineering Sichuan UniversityChengdu 610065SichuanChina Department of Chemistry Sichuan UniversityChengdu 610064SichuanChina

The activation of methane on graphite surfaces with monovacancies and 5-8-5 vacancies have been investigated using density functional theory. Sixteen different initial adsorption configurations were investigated to identify the most favorable activation site. It is found that methane tends to be activated on the defective graphite surfaces, and the most stable configuration is that methane activation happened in the center hole of the monovacancy site, with a reaction energy of 1.13 eV. Electron transfer and weaker electrostatic potential of the vacancy region indicate that carbon atom of methane tends to fill the vacancy and makes the system more stable.

关键词： density functional calculations defective graphite methane activation

Effects of impregnation sequence on the microstructure and performances of Cu-Co based catalysts for the synthesis of higher alcohols

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Journal of Natural Gas Chemistry 2008年第4期17卷 369-373页

作者： Siyu Deng wei chu Huiyuan Xu Limin Shi Lihong Huang Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China

Silica-supported CuCo catalysts were prepared by impregnation method with different impregnation sequence for higher alcohols synthesis. These catalysts were characterized by H2-TPR, XRD, N2 adsorption, XPS techniques and CO selective hydrogenation reaction measurement. The effects of impregnation sequence on the structure and performance of catalysts were investigated, and there were important influences on the selectivity to higher alcohols. There was a strong synergistic effect between copper and cobalt for the co-impregnated sample. The CuCo/SiO2 catalyst prepared by co- impregnation showed a better yield of total alcohols, and a higher selectivity to total alcohols which reached 51.5%.

关键词： copper cobalt impregnation sequence synergistic effect selective hydrogenation carbon monoxide

Event-driven process execution model for process virtual machine

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计算机集成制造系统 2012年第8期18卷 1675-1685页

作者： WU Dong-yao wei Jun GAO chu-shu DOU Wen-shen Technology Center for Software Engineering Institute of Software Chinese Academy of Sciences Beijing 100090 China

Current orchestration and choreography process engines only serve with dedicate process *** solve these problems,an Event-driven Process Execution Model(EPEM) was *** and mapping principles of the model were presented to guarantee the correctness and efficiency for process *** a case study,the EPEM descriptions of Web Services Business Process Execution Language(WS-BPEL) were represented and a Process Virtual Machine(PVM)-OncePVM was implemented in compliance with the EPEM.

关键词： business process modeling event-driven architecture process virtual machine service orchestration process execution language

Effects of cerium precursors on surface properties of mesoporous CeMnO_x catalysts for toluene combustion

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Journal of Rare Earths 2020年第1期38卷 70-75页

作者： Changyu Zhang wei chu Feng Chen Lei Li Ruiyu Jiang Jinlong Yan School of Environment and Safety Engineering Changzhou UniversityChangzhou 213164China School of Environmental Science and Engineering Yancheng Institute of TechnologyYancheng 224051China Department of Chemical Engineering Sichuan UniversityChengdu 610065China Jiangsu Key Laboratory for Environment Functional Materials Suzhou University of Science and TechnologySuzhou 215009China

Mesoporous CeMnOx composite oxides catalysts were prepared by surfactant-assisted co-precipitation method and used for the catalytic oxidation of *** effect of different cerium precursors[Ce(NO3)3 and(NH4)2 Ce(NO3)6] on catalyst structure,surface properties and toluene combustion activities of mesoporous CeMnOx catalysts were *** Ce(Ⅲ)MnOx catalyst prepared from Ce(NO3)3 precursor shows higher catalytic activity,with a 90% conversion temperature of 240℃,which is better than the Ce(Ⅳ)MnOx catalyst derived from[(NH4)2 Ce(NO3)6] *** the basis of characterizations,it reveals that abundant surface content of Mn4+,better redox behavior and larger concentration of surface active oxygen species are responsible for the excellent catalytic performance.

关键词： Cerium precursor CeMnOx composite catalyst Synergistic effect Catalytic combustion Toluene Rare earths

Effect of different supports on activity of Mn-Ce binary oxides catalysts for toluene combustion

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Journal of Rare Earths 2022年第4期40卷 645-651,I0005页

作者： Lei Li Liping Song Zhaoyang Fei wei chu Xiaofeng Luo Jinlong Yan School of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Department of Chemical Engineering Sichuan UniversityChengdu 610065China

The effects of support materials on catalytic performance were investigated in catalytic removal of *** the Mn–Ce binary oxides as active components were supported on ZrO_(2),SiO_(2),γ-Al_(2)O_(3) and TiO_(2) support *** techniques,including X-ray diffraction(XRD),Brunauer–Emmett–Teller method(BET),X-ray photoelectron spectroscopy(XPS),temperature-programmed reduction(TPR)and NH_(3)-temperature-programmed desorption(NH_(3)-TPD),were used to characterize physicochemical *** the different catalysts,the MnCe/ZrO_(2) catalyst with the lowest specific surface area(39.7 m^(2)/g)shows the best catalytic *** terms of toluene conversion,the activity order is as follows:MnCe/ZrO_(2)>MnCe/TiO_(2)≈MnCe/SiO_(2)>MnCe/Al_(2)O_(3).The better performance of MnCe/ZrO_(2) should be attributed to the low-temperature reducibility,and abundant surface species(Mn^(4+)and lattice oxygen).And XPS and TPR results reveal that more surface abundant Mn and Ce elements generate good interaction in MnCe/ZrO_(2).The weak interaction between metal oxide and support also boosts the dispersion and complete reduction of MnCe oxides at low *** addition,the in-situ DRIFTS results clarify that the carbonate species are main intermediates in MnCe/ZrO_(2) sample during surface reaction process.

关键词： Synergistic effect Mn-Ce binary oxides Support property Catalytic combustion Toluene Rare earths