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Relationship between molecular structure and tribological properties of phosphazene lubricants

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Science china Mathematics 2001年第S1期44卷 182-187页

作者： YE Chengfeng LIU Weimin ZHANG Zefu YU Laigui state key {2. of solid lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China

Cyclotriphosphazene lubricants were synthesized and the relationship between theirstructures and tribological properties was investigated using an Optimol SRV oscillating frictionand wear tester and one-way reciprocating friction tester. It was found that aryloxyphosphazenewith polar substituent as a lubricant of steel/steel and steel/aluminum pair gave low wear, whilearyloxyphosphazene with nonpolar group on the phenyl pendant led to high wear. Phosphazeneprovides poor lubricity for steel/aluminum system under low load (0.5-3 N). The XPS analyticalresults of the antiwear films generated on the steel and aluminum surface indicate that phos-phazene reacted with steel or aluminum counterface and formed a surface protecting film consist-ing of fluoride and organic compounds containing O, C, F, N, P during friction. This contributes tcreduce the friction and wear of steel/aluminum system.

关键词： phosphazene lubricant wear friction SEM/EDS XPS

TPSR STUDIES OF METHANE ACTIVATION ON SUPPORTED TRANSITION METAL CATALYSTS

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chinese Journal of Catalysis 1996年第2期17卷 89-90页

作者： Yan Zifeng (Department of chemical Engineering, University of Petroleum, Dongying 2.7062.Xue Jinzhen Shen Shikong (state {2. laboratory of Oxo Synthesis and Selective Oxidation, lanzhou instituteof chemical physics, chinese academy of sciences, lanzhou 7 Department of chemical Engineering University of Petroleum Dongying 257062 state key {2. of Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000

ＴＰＳＲＳＴＵＤＩＥＳＯＦＭＥＴＨＡＮＥＡＣＴＩＶＡＴＩＯＮＯＮＳＵＰＰＯＲＴＥＤＴＲＡＮＳＩＴＩＯＮＭＥＴＡＬＣＡＴＡＬＹＳＴＳ￥ＹａｎＺｉｆｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，... 详细信息

ＴＰＳＲＳＴＵＤＩＥＳＯＦＭＥＴＨＡＮＥＡＣＴＩＶＡＴＩＯＮＯＮＳＵＰＰＯＲＴＥＤＴＲＡＮＳＩＴＩＯＮＭＥＴＡＬＣＡＴＡＬＹＳＴＳ￥ＹａｎＺｉｆｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＵｎｉｖｅｒｓｉｔｙｏｆＰｅｔｒｏ...

关键词： methane activation transition metal surface carbon species

The first observation of Mo^(5+) in the passivation layer of Mo_2.

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chinese Science Bulletin 2000年第17期45卷 1562-1564页

作者： XIE Guohuang & JIANG ZhichengStale key laboratory of Oxo-Synthesis and Selective Oxidation,{2., chinese academy ofsciences, lanzhou 730000, chinaCorrespondence should he addressed to Jiang Zhicheng state key {2. of Oxo-Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

Molybdenum nitride powder with sg of 115 m2............... g 1 (passivated) has been prepared by a temperature programmed reaction of MoO3 in H2.N2.mixture. It exhibited high catalytic activity in CO oxidation at low temperature. XPS, EPR and LRS studies have shown the existence of mixed valence states of Mo ions, especially Mo5+ ion (g=1.932. g =1.892. observed for the first time, in the passivation layer of molybdenum nitride. A surface superoxide species, O2.(g = 2.001, Ramanband 1 12. cm 1), was found to be produced accompanying the transformation of Mo5+/Mo4+ redox pair. Evidence has been given to suggest that this surface superoxide might be responsible for CO oxidation over Mo2. catalyst.

关键词： molybdenum nitride passivation layer Mo XPS EPR LRS.

Catalytic Synthesis of Lower Hydrocarbons from CO2.Hydrogenation over Supported Iron Catalys

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分子催化 1997年第3期 2-3页

作者： REN Xu KOU Yuan 1) NIU Jianzhong WANG Hongli (state key {2. for Oxo Synthesis and Selective Oxidation lanzhou institute of chemical physics The chinese academy of sciences lanzhou 73000)

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ＣａｔａｌｙｔｉｃＳｙｎｔｈｅｓｉｓｏｆＬｏｗｅｒＨｙｄｒｏｃａｒｂｏｎｓｆｒｏｍＣＯ２ＨｙｄｒｏｇｅｎａｔｉｏｎｏｖｅｒＳｕｐｐｏｒｔｅｄＩｒｏｎＣａｔａｌｙｓｔＲＥＮＸｕＫＯＵＹｕａｎ１）ＮＩＵＪｉａｎｚｈｏｎｇＷＡＮＧＨｏｎｇｌｉ（ＳｔａｔｅＫ...

关键词： Iron catalyst Ceria Hydrogenation of CO 2 Mssbauer XRD EXAFS

Interfacial behaviors of PMMA-PEO block copolymers at the air/water interface

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Science china Chemistry 2005年第6期48卷 567-573页

作者： CHENG Caixia1, JIAO Tifeng2. TANG Rupei1, LIU Minghua2.& XI Fu1 1. state key {2. of Polymer physics and Chemistry, Joint {2. of Polymer Science and Materials, institute of Chemistry, chinese academy of sciences, Beijing 100080, china 2. CAS key {2. of Colloid and Interface Science, institute of Chemistry, chinese academy of sciences, Beijing 100080, china 1. state key {2. of Polymer physics and Chemistry Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 2. CAS key laboratory of Colloid and Interface Science Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China

Diblock copolymer of PMMA2.1-b-PEO114 and triblock copolymer of PMMA12.-b- PEO2.7-b-PMMA12. were synthesized and their interfacial properties at the air-water interface were investigated, where both blocks of polyethylene oxide (PEO) and poly(methyl methacrylate) (PMMA) are surface active but the former is soluble in water while the latter is not. Both the block copolymers could form monolayers with two obvious transition regions. The first transition point is around 10 mN/m, which could be assigned to the pancake-brush change of the PEO chains. The other is around 18 mN/m, which could be ascribed to the condensed packing of PMMA. The surface morphological changes during the compression of the Langmuir monolayers are inves-tigated by using the AFM and SEM methods for the films deposited at different surface pressure or molecular areas. At a lower surface pressure, a typical morphology of PEO-con- taining lipopolymers is observed. Upon compression, sphere-dominant morphologies were observed. While the diblock copolymer is easy to folding, the triblock copolymer is in favor of formation of circular domains through vesiculation.

关键词： PMMA-PEO, block copolymers, monolayer, Langmuir-Blodgett films, AFM.

Study on corrosive grinding of gears

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Science china Mathematics 2001年第S1期44卷 263-266页

作者： XIA Yanqiu LIU Weimin YU Laigui Xue Qunji state key {2. of solid lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China

Careful grinding or honing is usually required in machining of gears in order to improvethe machining quality of gear surface. Thus several grinding additives were used to formulate syn-thetic grinding lubricants similar to superior running-in lubricants. Experimental results show thatthe tooth surface of the produced oblique gear and steel worm becomes extremely smooth aftergrinding at a certain load for about a half to one hour. Especially, the gear surface finished withspecially formulated grinding lubricant reaches mirror-like smoothness. The quality of the geartooth can be improved by corrosive grinding, while the corrosive grinding time can be controlled byadjusting the quantity of the corrosive additives and the speed and load of the gears.

关键词： gear grinding additives corrosive grinding

Preparation of InSb nanocrystals embedded in SiO_2.thin films

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chinese Science Bulletin 1998年第19期43卷 1610-1615页

作者： ZHU Kaigui 1, SHI Jianzhong 1, WEI Yanfeng 2.and ZHANG Lide 1 1. institute of solid {2. physics, chinese academy of Science, Hefei 2.0031, china 2. {2. key laboratory of Surface physics, Fudan University, Shanghai 2.0433, china institute of solid {2. physics Chinese Academy of Science Hefei China state key {2. of Surface physics Fudan University Shanghai China

InSb nanocrystals embedded in SiO 2.thin films were prepared by rf magnetron cosputtering technique. THe observation by transmission electron microscope showed that InSb nanocrystals dispersed uniformly in SiO-2.matrices. InSb nanocrystals with different sizes can be obtained by changing the annealing condition. The average size of InSb nanocrystals depended on annealing temperature and time, but not on the t 1/3 rules. X-ray photoelectron spectroscopy and X-ray diffraction were also applied to the analyses of the composite thin films.

关键词： InSb nanocrystals radio-frequency sputtering quantum confinement.

Research progress in terahertz quantum cascade lasers

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Science china(Information sciences) 2012年第1期55卷 16-26页

作者： CAO JunCheng key laboratory of Terahertz {2.-state Technology,Shanghai institute of Microsystem and Information Technology,chinese academy of sciences,Shanghai 2.0050,china 1. key laboratory of Terahertz {2.-state Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

The terahertz(THz)quantum cascade laser(QCL)is a coherent THz source based on intersubband transitions of unipolar *** semiconductor lasers,THz QCLs are solid-state,electrically pumped,tunable,and can be easily *** paper reviews the state of the art for the design,operation temperature,and output power of THz *** applications in THz communication and imaging are also discussed.

关键词： terahertz quantum cascade laser communication imaging

Wet-chemical synthesis and characteristics of Au nanoshell

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Science china Chemistry 2005年第5期48卷 431-435页

作者： LIU Zhongxin1,2. SONG Hongwei1, YU Lixin1,2. YANG Linmei1,2.& PAN Guohui1,2.1. key laboratory of Excited {2. physics, Changchun institute of Optics, Fine Mechanics and physics, chinese academy of sciences, Changchun 130033, china 2. Graduate School of the chinese academy of sciences, Beijing 100039, china 1. key laboratory of Excited {2. physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 2. nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 30℃ (5 W/cm2. irradiation area was 2.cm2.. This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.