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Reaction Chemistry of W-Mn/SiO2 Catalyst for the Oxidative Coupling of Methane

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Journal of Natural Gas Chemistry 2003年第1期12卷 1-9页

作者： Shuben LiState Key Laboratory for Oxo Synthesis and Selective Oxidation, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Reaction chemistry of the OCM reaction on W-Mn/SiO_2 catalyst has beenreviewed in this account. Initial activity and selectivity, stability in a long-term reaction,reaction at elevated pressures and a modelling test in a stainless-steel fluidized-bed reactor showthat W-Mn/SiO_2 has promising performance for the development of an OCM process that directlyproduces ethylene from natural gas. A study on surface catalytic reaction kinetics and used catalyststructure characterization revealed a possible reason why C_2 and CO_x selectivity changed duringthe long-term reaction. Further improvement of the catalyst composition and preparation methodshould be a future direction of study on OCM reaction over W-Mn/SiO_2 catalyst.

关键词： W-Mn/SiO_2 catalyst oxidative coupling of methane elevated pressure methane

Enthalpy and entropy interaction parameters of sodium chloride with some monosaccharides in water

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Science china Chemistry 2004年第1期47卷 59-66页

作者： ZHUO Kelei, WANG Jianji, BAI Guangyue, YAN Haike & WANG HangingSchool of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453002, china institute of Chemistry, chinese academy of sciences, Beijing 100080, china lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china School of Chemistry and Environmental Science Henan Normal University Xinxiang China institute of Chemistry Chinese Academy of Sciences Beijing China lanzhou institute of chemical physics Chinese Academy of Sciences Lanzhou China

Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules. Keywords sodium chloride - monosaccharide - enthalpy interaction parameter - entropy interaction parameter - calorimetry

关键词： sodium chloride, monosaccharide, enthalpy interaction parameter, entropy interaction parameter, calorimetry.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2,REN WeiJia1,WANG ShiDa1 & WENG LiJun3 1 academy of Opto-Electronics,chinese academy of sciences,Beijing 100190,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3 lanzhou institute of chemical physics,chinese academy of sciences,lanzhou 730000,china academy of Opto-Electronics Chinese Academy of Sciences Graduate University of chinese academy of sciences

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2 , LIU Weimin 2 & LIANG Yongmin 2 1. School of chemical Engineering and Technology, china University of Mining and Technology, Xuzhou 221008, china 2. State Key Laboratory of Solid Lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china School of chemical Engineering and Technology China University of Mining and Technology Xuzhou 221008 China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4 ) 2 plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

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 State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

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

Theoretical study of the interaction mechanism of single-electron halogen bond complexes H_3C…Br-Y(Y=H,CN,NC,CCH,C_2H_3)

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Science china Chemistry 2010年第1期53卷 216-225页

作者： LI ZhiFeng1,SHI XiaoNing1,TANG HuiAn1 & ZHANG JunYan2 1College of Life Science and Chemistry,Tianshui Normal University,Tianshui 741001,china 2lanzhou institute of chemical physics,chinese academy of sciences,lanzhou 730000,china College of Life Science and Chemistry Tianshui Normal University Tianshui China lanzhou institute of chemical physics Chinese Academy of Sciences Lanzhou China

The characteristics and structures of single-electron halogen bond complexes H3C…Br-Y(Y = H,CCH,CN,NC,C2H3) have been investigated by theoretical calculation *** geometries were optimized and frequencies calculated at the B3LYP/6-311++G *** interaction energies were corrected for basis set superposition error(BSSE) and the wavefunctions obtained by the natural bond orbital(NBO) and atom in molecule(AIM) analyses at the MP2/6-311++G *** each H3C…Br-Y complex,a single-electron Br bond is formed between the unpaired electron of the CH3(electron donor) radical and the Br atom of Br-Y(electron acceptor);this kind of single-electron bromine bond also possesses the character of a"three-electron bond".Due to the formation of the single-electron Br bond,the C-H bonds of the CH3 radical bend away from the Br-Y moiety and the Br-Y bond elongates,giving red-shifted single-electron Br bond *** effects of substituents,hybridization of the carbon atom,and solvent on the properties of the complexes have been *** strengths of single-electron hydrogen bonds,single-electron halogen bonds and single-electron lithium bonds have been *** addition,the single-electron halogen bond system is discussed in the light of the first three criteria for hydrogen bonding proposed by Popelier.

关键词： single-electron halogen bond single-electron hydrogen bond single-electron lithium bond MP2 DFT NBO AIM

Microstructure and Tribological Properties of TiB_2/TiB/TiN_x(x=1,0.3)/Ti Composite Coating Produced on Pure Ti by Laser Surface Alloying

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稀有金属材料与工程 2012年第S1期41卷 344-349页

作者： Guo Chun1,2,Chen Jianmin1,Zhou Jiansong1,Zhao Jierong1,2,Wang Lingqian1,2,Yu Youjun1,2,Zhou Huidi 1 1 lanzhou institute of chemical physics,chinese academy of sciences,lanzhou 730000,china 2 Graduate University of chinese academy of sciences,Beijing 100039,china chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100039 Peoples R China

TiB2/TiB/TiNx(x=1,0.3)/Ti composite coating was prepared on pure Ti by laser surface alloying by using powders of boron as starting *** composite coating was examined by X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM)and scanning electron microscopy(SEM).The friction and wear properties of the composite coating were examined using a pin-on-disk tester under dry sliding wear *** results showed that the top surface of the composite coating was mainly composed of TiB2,TiB,TiN0.3,TiN and Ti phases,while the interface of the composite coating was composed of TiB and Ti *** composite coating showed sticklike structure near the top surface,and dendrites structure near the *** friction and wear test showed that the composite coating had better wear resistance than pure Ti due to their higher microhardness than that of pure Ti substrate.

关键词： pure Ti laser surface alloying TiB2 composite coating friction and wear property

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

Wear Behavior of Cu Matrix Composites Reinforced with Mixture of Carbon and Carbon Nanotubes

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Journal of Wuhan University of Technology(Materials Science) 2009年第2期24卷 254-257页

作者：姜金龙 School of Science Lanzhou University of Technology State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

In order to improve wear resistance and decrease the cost, carbon and carbon nanotubes reinforced copper matrix composites were fabricated by the power metallurgy method. The effects of carbon （carbon and carbon nanotubes） volume fraction and applied load on the friction coefficient and wear rate under dry sliding of the composites were investigated at room temperature. By scanning electron microscopy （SEM）, the worn surfaces and debris were observed, and wear mechanism was also analyzed and discussed. The experimental wear process consists of the run-in, steady wear and severe wear process with the increasing of sliding distance. Both the friction coefficient and wear rate of the composites first decrease and then increase with the increasing of carbon volume fraction. The minimum friction coefficient and wear rate are obtained when carbon is 4.0vo1%. The wear mechanisms of the composites change from the adhesive wear and delamination wear to abrasive wear with the increasing of carbon volume fraction.

关键词： C/Cu matrix composite power metallurgy wear behavior