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Hydrocarboxylation of styrene in Water-soluble Catalyst system Pd(OAc)2-TPPTsH-HOAc-H2O

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分子催化 1997年第2期 2-3页

作者： XIE Baohan KOU Yuan * YINGYuanqi (state key laboratory for Oxo synthesis and selective Qxidation lanzhou institute of chemical physics The chinese academy of sciences lanzhou 730000)

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ＨｙｄｒｏｃａｒｂｏｘｙｌａｔｉｏｎｏｆＳｔｙｒｅｎｅｉｎＷａｔｅｒ┐ＳｏｌｕｂｌｅＣａｔａｌｙｓｔＳｙｓｔｅｍＰｄ（ＯＡｃ）２┐ＴＰＰＴＳＨ┐ＨＯＡｃ┐Ｈ２ＯＸＩＥＢａｏｈａｎＫＯＵＹｕａｎ＊ＹＩＮＧＹｕａｎｑｉ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔｏｒ...

关键词： Hydrocarboxylation styrene Water soluble catalyst Palladium acetate

Microstructure and Wear Resistance Evolution of HVOFsprayed WC-(W,Cr)_2C-Ni Coating with Post Heat Treatment In Air Atmosphere

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稀有金属材料与工程 2012年第S1期41卷 388-393页

作者： Hou Guoliang1,2,Zhou Huidi1,An Yulong1,2,Liu Guang1,2,Chen Jianmin1,Chen Jie1,2 1 state key laboratory of solid Lubrication,lanzhou institute of chemical physics,chinese academy of sciences,lanzhou 730000,china 2 Graduate University,chinese academy of sciences,Beijing 100049,china chinese Acad sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China chinese Acad sci Grad Univ Beijing 100049 Peoples R China

WC-(W,Cr)2C-Ni coating was prepared on 1Cr18Ni9Ti stainless steel and C-276 Ni-base Hastelloy by high velocity oxy-fuel(HVOF)*** effect of post heat treatment in air atmosphere on the microstructure,phase composition,microhardness,fracture toughness,and wear resistance of HVOF-sprayed WC-(W,Cr)2C-Ni coating was *** microstructure and phase composition of the coatings were analyzed by means of field emission scanning electron microscopy(FEsEM)and X-ray diffraction(XRD).The microhardness and fracture toughness of the coatings were measured using a microhardness tester and a Vickers hardness ***,dry friction and wear behavior of the coatings sliding against si3N4 ball was investigated using an oscillating friction and wear tester;and the worn surfaces of the coatings were analyzed by means of scanning electron microscopy(sEM).It was found that heat treatment within 500-800°C resulted in crystallization of amorphous phase in as-sprayed coating,generating nanoscale new phases such as NiWO4,CrWO4 and ***,heat treatment led to increase of the microhardness of as-sprayed coating,and the highest microhardness was obtained after heat treatment at 800°*** fracture toughness and wear resistance of the as-sprayed coating increased with increasing heat treatment temperature up to 700°C but tended to decrease with further elevating *** other words,the mechanical properties and wear resistance of the as-sprayed coatings were worsened owing to excessive growth of oxidation grains and depletion of ductile Ni binder after heat treatment above 700°*** it was suggested that as-sprayed ceramic composite coating should be post heat treated in air at a moderate temperature of 700°C so as to achieve the optimized mechanical properties and wear resistance.

关键词： HVOF WC-(W,Cr)2C-Ni coating post heat treatment microstructure wear resistance

Nonlinear local Lyapunov exponent and atmospheric predictability research

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science china Earth sciences 2006年第10期49卷 1111-1120页

作者： CHEN Baohua1, LI Jianping1,2 & DING Ruiqiang2 1. College of Atmospheric sciences, lanzhou University, lanzhou 730000, china 2. state key laboratory of Numerical Modeling for Atmospheric science and Geophysical Fluid Dynamics (LAsG), institute of Atmospheric physics, chinese academy of sciences, Beijing 100029, china College of Atmospheric sciences Lanzhou University Lanzhou China state key laboratory of Numerical Modeling for Atmospheric science and Geophysical Fluid Dynamics (LAsG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

Because atmosphere itself is a nonlinear system and there exist some problems using the linearized equations to study the initial error growth, in this paper we try to use the error nonlinear growth theory to discuss its evolution, based on which we first put forward a new concept: nonlinear local Lyapunov exponent. It is quite different from the classic Lyapunov exponent because it may characterize the finite time error local average growth and its value depends on the initial condition, initial error, variables, evolution time, temporal and spatial scales. Based on its definition and the at-mospheric features, we provide a reasonable algorithm to the exponent for the experimental data, obtain the atmospheric initial error growth in finite time and gain the maximal prediction time. Lastly, taking 500 hPa height field as example, we discuss the application of the nonlinear local Lyapunov exponent in the study of atmospheric predictability and get some reliable results: atmospheric predictability has a distinct spatial structure. Overall, predictability shows a zonal distribution. Prediction time achieves the maximum over tropics, the second near the regions of Antarctic, it is also longer next to the Arctic and in subtropics and the mid-latitude the predictability is lowest. Particularly speaking, the average prediction time near the equation is 12 days and the maximum is located in the tropical Indian, Indonesia and the neighborhood, tropical eastern Pacific Ocean, on these regions the prediction time is about two weeks. Antarctic has a higher predictability than the neighboring latitudes and the prediction time is about 9 days. This feature is more obvious on southern Hemispheric summer. In Arctic, the predictability is also higher than the one over mid-high latitudes but it is not pronounced as in Antarctic. Mid-high latitude of both Hemispheres (30°s―60°s, 30°―60°N) have the lowest predictability and the mean prediction time is just 3―4 d. In addition, predictab

关键词： nonlinear, local, Lyapunov exponent, atmospheric predictability, maximal prediction time.

Investigation on the Performance of supported Molybdenum Carbide for the Partial Oxidation of Methane

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Journal of Natural Gas Chemistry 2003年第1期12卷 23-30页

作者： Quanli Zhu, Jian Yang, Jiaxin Wang, shengfu Ji, Hanqing Wangstate key laboratory for Oxo synthesis and selective Oxidation, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china stt. key Lab. Oxo synth./sel. Oxid. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The performance of supported and unsupported molybdenum carbide for thepartial oxidation of methane (POM) to syngas was investigated. An evaluation of the catalystsindicates that bulk molybdenum carbide has a higher methane conversion during the initial stage buta lower selectivity to CO and H_2/CO ratio in the products. The rapid deactivation of the catalystis also a significant problem. However, the supported molybdenum carbide catalyst shows a muchhigher methane conversion, increased selectivity and significantly improved catalytic stability. Thecharacterization by XRD and BET specific area measurements depict an improved dispersion ofmolybdenum carbide when using alumina as a carrier. The bulk or the supported molybdenum carbideexists in the β-MO_2C phase, while it is transformed into molybdenum dioxide postcatalysis which isan important cause of molybdenum carbide deactivation.

关键词： molybdenum carbide molybdenum oxide partial oxidation of methane syngas deactivation

Magnetic characteristics of dustfall in urban area of north china and its environmental significance

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science china Earth sciences 2007年第11期50卷 1724-1732页

作者： XIA Dunsheng1,2, YANG LiPing2, MA JianYing1, YU Ye1, WANG Guan2 & CHEN FaHu2 1 key laboratory of Desert and Desertification, institute of Cold and Arid Regions Environmental and Engineering, chinese academy of sciences, lanzhou 730000, china 2 CAEP, key laboratory of West china’s Environmental system (Ministry of Education), lanzhou University, lanzhou 730000, china key laboratory of Desert and Desertification Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China CAEP Key Laboratory of West China’s Environmental System (Ministry of Education) Lanzhou University Lanzhou China

Urban particulate pollutants not only affect urban air quality but also directly threaten public health. lanzhou has been one of the most seriously polluted cities in the world due to its special geophysical location and weather conditions, which makes it an ideal place for urban particulate pollution study. In this study a set of environmental magnetic parameters (χ_(1f),χ_(fd)%, χ_(ARM), sIRM, HIRM, sOFT and back field IRM) were measured and analyzed for the dustfall samples collected monthly during 1997.4—2000.5 and 2004.11—2005.10 at lanzhou University campus (KLD and CCs) and at a clear site of Gaolanxian (GLX). Results demonstrate that the main magnetic minerals in the dustfall are magnetite, with some maghaemite and haematite. Cross plots of M_(rs)/M_s vs. B_(cr)/B_c and χ_(fd)% vs. χ_(ARM)/sIRM indicate that the main magnetic grain sizes are pseudo-single-domain (PsD). The high concentration of magnetic minerals in the dustfall indicates that lanzhou is seriously polluted. The main pollution sources are anthropogenic activities and nature dust, with the former posing a great threat during the whole year, which is different from the general view that the natural dust is the main contributor in summer. With great efforts of the government and local authority in the past decades, the air quality in lanzhou has been improved in winter, but it is not so obvious in summer. This study also reveals that as a simple, rapid and accurate technology, environmental magnetism could be a valuable tool for urban pollution study.

关键词： environmental magnetism,dustfall,air pollution,lanzhou

studies on the Reaction Mechanism of CO_2-Reforming of Methane over Co/γ-Al_2O_3 Catalyst

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chinese chemical Letters 1997年第2期8卷 121-124页

作者： Yong LU Chang Chun YU Jin Zhen XUE Yu LIU Xue Jia DING and shi Kong sHEN(state key laboratory of Oxo synthesis and selective Oxidation,lanzhou institute of chemical physics,chinese academy of sciences. lanzhou 730000) state key Lab. Oxo synthesis/s. O. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

TPPR and XPs characterizations were combined to study the reaction mechanism of CO2reforming of methane to syngas over Co/γ-Al2O3 catalysts. CH4 shows a tendency to form surface carbons by deep dissociation at high temperatures. CO2 dissociation reaction also occurs at >673K. It is believed that carbide carbons are active species to generate CO by rcacting with o atoms dissociated from CO2. In the reaction,Co(0) particles are responsible for dissociating CH4 to form active C. abstracting an O atom from CO2 molecule, and transferring O atom to C to form CO.

关键词： over CO Al2O3 Catalyst studies on the Reaction Mechanism of CO2-Reforming of Methane over Co

Preparation and Characterization of ZrO_2 Nanoparticles Capped by Trioctylphosphine Oxide (TOPO)

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Journal of Wuhan University of Technology(Materials science) 2011年第4期26卷 611-614页

作者：马剑琪 school of Chemistry and Environmental science Shaanxi University of Technology state key laboratory of solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Monodisperse ZrO2 nanoparticles capped by trioctylphosphine oxide （TOPO） were prepared in non-aqueous solvent using in-situ synthesis method. Transmission electron microscopy（TEM）, X-ray diffraction（XRD）, X-ray photoelectron spectrometer（XPs）, Fourier transformation infrared spectroscopy （FTIR）, and thermogravimetric analysis（TGA） were adopted to characterize and investigate the size, structure, composition, and the binding manners between organic capping agent TOPO and inorganic ZrO2 nanocores of the as-prepared nanoparticles. In addition, the nanoparticles were also studied to determine their solubility and relative stability. The experimental results show that the prepared nanoparticles contain about 25% organic capping shell TOPO, 75% inorganic ZrO2 nanocores, and can be easily dissolved and be stably disersed in non-polar organic solvents.

关键词： ZrO2 nanoparticles trioctylphosphine oxide (TOPO) monodisperse solubility

Hydrogenation of CO2 over Alumina-Modified

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分子催化 1997年第4期 4-5页

作者： REN Xu KOU Yuan 1) WANG Hongli (state key laboratory for Oxo synthesis and selective Oxidation lanzhou institute of chemical physics The chinese academy of sciences lanzhou 730000)

ＨｙｄｒｏｇｅｎａｔｉｏｎｏｆＣＯ２ｏｖｅｒＡｌｕｍｉｎａＭｏｄｉｆｉｅｄＺｉｒｃｏｎｉａＳｕｐｐｏｒｔｅｄＩｒｏｎＣａｔａｌｙｓｔＲＥＮＸｕＫＯＵＹｕａｎ１）ＷＡＮＧＨｏｎｇｌｉ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔ... 详细信息

ＨｙｄｒｏｇｅｎａｔｉｏｎｏｆＣＯ２ｏｖｅｒＡｌｕｍｉｎａＭｏｄｉｆｉｅｄＺｉｒｃｏｎｉａＳｕｐｐｏｒｔｅｄＩｒｏｎＣａｔａｌｙｓｔＲＥＮＸｕＫＯＵＹｕａｎ１）ＷＡＮＧＨｏｎｇｌｉ（ＳｔａｔｅＫｅｙＬａｂｏｒａｔｏｒｙｆｏｒＯｘｏＳｙｎｔｈｅｓｉ...

关键词： Iron catalyst Zirconia Hydrogenation of CO 2 XRD EXAFs

MECHANIsM OF sULFUR POIsONING AND REGENERATION METHODs FOR sUPPORTED METAL CATALYsTs Ⅰ. MECHANIsM OF sULFUR POIsONING OF Pd(Pt)/Al_2O_3 CATALYsTs IN H_2-O_2 REACTION

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分子催化 1990年第S1期4卷 23-32页

作者： Deng Youquan An Lindun(lanzhou institute of chemical physics, chinese academy of sciences, lanzhou, china)

sulfur poisoning mechanism of Pd（Pt）/Al2O3 catalysts for H2—O2 reaction was studied by means of micro-catalytic reaction chromatograph, TPR, XPs, AEs, XRD and IR. The results show that the tolerance of Pd/Al2O3 cat... 详细信息

sulfur poisoning mechanism of Pd（Pt）/Alsub>2sub>Osub>3sub> catalysts for Hsub>2sub>—Osub>2sub> reaction was studied by means of micro-catalytic reaction chromatograph, TPR, XPs, AEs, XRD and IR. The results show that the tolerance of Pd/Alsub>2sub>Osub>3sub> catalysts to surfur poisoning is significantly affected by the Osub>2sub>/Hsub>2sub> ratio and enhanced with the increase of the ratio. In″weak″oxidizing atmosphere, the deactivation is swift and irreversible because of the active components, particularly at the surface, being seriously sulfided by ssup>-2sup>. In ″strong″ oxidizing atmosphere, the poisoning caused by ssup>-2sup> is reversible to great extent owing to the reaction Msub>ssub>—s/Alsub>2sub>Osub>3sub>（Osub>2sub>,Hsub>2sub>O）/catalyst（Msub>ssub>（Msub>ssub>O）/Alsub>2sub>Osub>3sub>-sOsub>3sub>-Hsub>2sub>O）where Msub>ssub> signifies Pd or Pt on the surface. But, when the sulfate in catalyst is accumulated in large amount, it could cover or block the active sites, which may be an important cause of the catalyst deactivation in addition to the sulfidization of metal components.

关键词： poisoning oxidizing seriously irreversible accumulated sulfur Pt sulfur appearance latter