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Trend and Development of Semi-solid Metal Processing

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Journal of Materials Science & Technology 2000年第5期16卷 453-460页

作者： Xianfeng PAN, Haifeng ZHANG, Aimin WANG, Bingzhe DING, Keqiang QIU and Zhuangqi HU (state key {2. of Rapidly solidified Nonequilibrium Alloys, institute of Metal Research, chinese academy of sciences, Shenyang 110015, china) state key {2. of Rapidly solidified Nonequilibrium Alloys Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

This paper reviewed the trend and development of semi-solid metal technique. The processes and mechanisms for producing slurry of SSM and its industrial applications have been summarized and discussed. Discussions on the basic rheological theory are presented for more applications. Further consideration of the development and application of SSM technique is also proposed.

关键词： SSM Trend and Development of Semi-solid Metal Processing

ANNUAL LAMINATIONS IN THE SEDIMENTS OF HONGFENG LAKE, china

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chinese Geographical Science 1996年第4期6卷 375-382页

作者： Wu Fengchang Wan Guojiang(state key {2. of Environmental Geochemistry, institute of Geochemistry, the chinese academy of sciences, Guiyang 550002. PRC) state key {2. of Environmental Geochemistry Institute of Geochemistry the Chinese Academy of Sciences Guiyang PRC

Hongfeng Lake is an eutrophic freshwater atificial *** began to restore water in 1960. Three sediment cores were taken from both about 2.m of water in the center of Hongfeng bake in May 1991. The stratigraphy of the three cores was easily matched .by using prominent marking horizons and characteristic aqnences of laminations. In three layer Samples studied, diatom and other algae taxa appear in repeating apuences. The presence of laminations may reflect either the regular changes of physical-chemical conditions within the lake or the variation in the intensity of erosion and transport of material from the catchment, pat iculaly where instability in the lake-water system has occult as a result of human activities. The larninations were mainly cantal by seasonal variation of envionmental conditions,particularly *** t of the previous examples, they have ben fo￣ at most recent Sediments, in a small freshwater lake in the eastern slOPe of the QinghaiXiZang Plateau, china in a subtropical climate, which is adenly controlled by ￣theastern and southwestern mon￣n. It is believed that it's the first reported instanceOf laminated lake sediments from china.

关键词： annual laminations Hongfeng Lake carbonate geochemistry

MB_8^(2.) (M=Be,Mg,Ca,Sr,and Ba):Planar octacoordinate alkaline earth metal atoms enclosed by boron rings

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Science china Chemistry 2010年第8期53卷 1737-1745,1829-1832页

作者： PU ZhiFeng1,GE MaoFa1 & LI QianShu2.1state key {2. for Structural Chemistry of Unstable and Stable Species Beijing National {2. for Molecular sciences (BNLMS) institute of Chemistry,chinese academy of sciences,Beijing 100190,china 2.enter for Computational Quantum Chemistry,South china Normal University,Guangzhou 510631,china 1. state key {2. for Structural Chemistry of Unstable and Stable Species Beijing National laboratory for Molecular sciences (BNLMS) institute of Chemistry Chinese Academy of Sciences Beijing 100190 China2. Center for Computational Quantum Chemistry South China Normal University Guangzhou 510631 China

Complexes involving planar octacoordinate alkaline earth metal atoms in the centers of eight-membered boron rings have been investigated by two density functional theory (DFT) ***82.with D8h symmetry is predicted to be stable,both geometrically and electronically,since a good match is achieved between the size of the central beryllium atom and the eight-membered boron *** contrast,the other alkaline earth metal atoms cannot be stabilized in the center of a planar eight-membered boron ring because of their large *** following the out-of-plane imaginary vibrational frequency,pyramidal C8v MgB82.,CaB82.,SrB82.,and BaB82.structures are *** presence of delocalized π and σ valence molecular orbitals in D8h BeB82.gives rise to aromaticity,which is reflected by the value of the nucleus-independent chemical *** D8h BeB82.structure is confirmed to be the global minimum on the potential energy surface.

关键词： density functional theory octacoordinate alkaline earth metal aromatic molecular orbital

The hydrogeochemistry of the Wujiang River drainage system in Guizhou, china (Ⅱ)——Variations in concentrations of dissolved trace elements in karst river water and their controlling factors

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chinese Science Bulletin 1999年第S2期44卷 112-115页

作者： LIU Congqiang and HAN Guilin state key {2. of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china state key {2. of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

GEOchemical studies of trace elements, especially heavy metal elements in river water will provide thegrounds for the assessment of the influence of human activities on the environment. At present, the stud- ies of water bodies in karst areas are focussed on the analysis of chemical compositions of surface and underground water samples, and almost no systematic study has been done on trace elements. So theauthors have carried out systematic studies on the distribution of concentrations of the dissolved trace elements and their controlling factors, while some systematic studies are under way on the major compositionsof river water in the Wujiang drainage system in Guizhou Province. On the basis of the characteristics ofthe U-Ca-Sr system in river water and their geochemical indicating implications (Refer to the paper entitled "The hydrogeochemistry of the Wujiang River drainage system in Guizhou, china: I. The U-Ca-Srsystem in karst river water"), the paper is concerned mainly with the trace element composition of

关键词： dissolved trace elements karst Wujiang River drainage system Guizhou china.

IR STUDIES ON SURFACE CHEMISTRY OF RHODIUM IN HYDROFORMYLATION CATALYSTS

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Journal of Energy Chemistry 1996年第3期 237-249页

作者： HUANG Lin XU Yi-De (state key {2. of CatalysisDalian institute of chemical physics, The chinese academy of sciencesDalian, Liaoning 11602.)

The interactions of supported Rh0 and cobalt- and iron- promotedRh0 with the SiO2.surfacc havc been investigated by IR spectroscopy. Thehighly dispersed rhodium particles dcrived by H2.decarbonylation ofRh6(CO)16/SiO2.are oxidized to isolated Rh+ by surface OH via heating at62. K under vacuum, which adsorbs CO to form R-h'(CO)2. The interactionsof added cobalt and iron with Rh0 suppress the oxidation of Rh0. Theresults show that the cobalt and iron promoters play an electron-donatingrole, thus increasing thc electron density of rhodium *** electroniceffect can be correlated with the observed promotion of catalytic ethylenehydroformylation. In situ IR observations indicate that supported Rh0 onRh/SiO2.is an activc site for hydrofonnylation.

关键词： SiO2.supported Rh Rh~0 oxidation promotion of cobalt and iron hydroformylation

COALESCENCE INDUCED GRADIENT MORPHOLOGY NEAR A WALL IN PHASE SEPARATED POLYMER BLENDS DURING QUIESCENT ANNEALING

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chinese Journal of Polymer Science 2002年第6期20卷 543-550页

作者： Wei Yu Chi-xing Zhou De-lu Zhao Department of Polymer Science and Engineering, Shanghai Jiao Tong University, Shanghai 2.02.0 china state {2. laboratory of Polymer physics and Chemistry, institute of Chemistry, chinese academy of sciences Beijing 100080, china Shanghai Jiao Tong Univ Dept Polymer Sci & Engn Shanghai 200240 Peoples R China chinese Acad Sci Inst Chem State Key Lab Polymer Phys & Chem Beijing 100080 Peoples R China

A fast coalescence mechanism is proposed to account for the wall effect on the formation of gradient morphology in phase separated polymer blends during quiescent annealing. The existence of solid wall with high polarity is believed to change the potential field around the dispersed particles near the wall. This additional potential interaction between the solid wall and the dispersed particles causes faster coalescence of the dispersed particles near the wall than in the bulk. The gradient phase morphology thus formed can be predicted by combining the wall-particle interaction and the touch-coalescence mechanism. The effect of interfacial tension on the gradient morphology is also discussed.

关键词： gradient morphology wall effect coalescence polymer blends interfacial tension

Influence of deposition time of TiN layer on the tribological properties of the Ti-TiN-TiCN coatings deposited by DCMS

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Influence of deposition time of TiN layer on the tribologica...

Expressed sequence tag analysis and cloning of trehalose-6-phosphate synthase gene from marine alga Laminaria japonica(Phaeophyta)

china 6th International Symposium on Tribology

作者： Jianyun Zheng~(1 2. Junying Hao~1 Xiaoqiang Liu~(1 2. Weimin Liu~1 1:state key {2. of solid lubrication lanzhou institute of chemical physics chinese academy of sciences lanzhou 730000 P.R.china 2.Graduate University of chinese academy of Science Beijing 100049 P.R.china

＜正＞*** For about three decades,titanium carbonitride（TiCN） coatings attract great attention due to their combined high hardness,high toughness,low friction coefficient, excellent wear and abrasion resistance[1-4].Generally, when preparing the TiCN coatings,many people most pay attention to deposition method,deposition parameters like gas composition and temperature,and doping of other elements[1,4,5-8].In this study,the Ti-TiN-TiCN coatings were synthesized by DCMS

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Acta Oceanologica Sinica 2012年第6期31卷 139-148页

作者： XUAN Jinsong 1,4,FENG Yanbin 1,WENG Manli 1,ZHAO Ge 1,SHI Jinfeng 1,YAO Jianting 2.WANG Xiuliang 2.GUO Baotai 3,QIAO Lixian 3,DUAN Delin 2.WANG Bin 1 1 The state key {2. of Plant Genomics,institute of Genetics and Developmental Biology,chinese academy of sciences,Beijing 100101,china 2.The state key {2. of Marine Biology,institute of Oceanology,chinese academy of sciences,Qingdao 2.6071,china 3 College of Life sciences,Qingdao Agricultural University,Qingdao 2.6109,china 4 Department of Biological Science and Engineering,School of chemical and Biological Engineering,University of Science and Technology Beijing,Beijing 100083,china 1. The state key {2. of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China 4. Department of Biological Science and Engineering School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China 2. The state key {2. of Marine Biology Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 3. College of Life sciences Qingdao Agricultural University Qingdao 266109 China

A high quality cDNA library was constructed from the brown alga Laminaria japonica,with the titer of 1.2.10 5 pfu/*** average insert size of the cDNA library is about 1.6 *** the cDNA library,591 cDNA clones were randomly selected and *** a result,574 EST(expressed sequence tag) sequences were *** of the 574 ESTs were submitted to the dbEST database section of GenBank with the accession numbers from CX942.2. to *** cDNA library was screened with a α-32.p labeled 453 bp T P S gene probe,which is a partial sequence yielded from Porphyra *** positive cDNA clones were screened and the sequencing data showed that these four cDNA clones covered majority of *** TPS cDNA *** PCR amplification,sequencing and assembling,the entire ORF(open reading frame) sequence of the T P S gene was obtained,which was named *** encodes a protein containing 908 amino acids with a calculated molecular mass of 101 674 *** LjTPS gene was successfully expressed in *** and *** LjTPS gene has potential application both in plant breeding to stress tolerance and in deciphering the T P S gene function and mechanism to stress tolerance.

关键词： cDNA library comparative study expressed sequence tag(EST) analysis Laminaria japonica trehalose-6-phosphate synthase(TPS) T P S gene

New Evidences for the Adsorption of Methane over Oxide Surfaces

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chinese chemical Letters 1996年第9期7卷 875+873-874页

作者： Fa Qiang XU Shi Kong SHEN Jin Zhen XUE(National Synchrotron Radiation laboratory.University of Science and Technology of china.Hefei 2.002..)({2. state laboratory for Oxo Synthesis and Selective Oxidation. lanzhou institute of chemical physics.chinese Ac UNIV SCI & TECHNOL china NATL SYNCHROTRON RADIAT LAB HEFEI 230029 PEOPLES R CHINA chinese ACAD SCI LANZHOU INST CHEM PHYS STATE KEY LAB OXO SYNTH & SELECT OXIDAT LANZHOU 730000 PEOPLES R CHINA

It is indicative of the TSR result that CH4 was strongly adsorbed on well degassed SrCO3 surface at high temperatUre.A desorption peak of CH4 was found in CH4TPD profile which appeared at ca. 310℃.The strong adsorption of CH4 over the surface of SrCO3 was attributed to the strong basicity of SrO sites resulted from decomposition of SrCO_3

关键词： over New Evidences for the Adsorption of Methane over Oxide Surfaces