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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South China

Science China Earth sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2. TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing institute of Geology and Palaeontology, chinese academy of sciences, Nanjing 2.0008, China 2. Henan institute of Geological Survey, Zhengzhou 450007, China 3. {3. key Laboratory of Geological Processes and Mineral Resources at China University of Geosciences, Wuhan 43.074, China 4. Faculty of Material sciences and chemical Engineering, China University of Geosciences, Wuhan 43.074, China 1. Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan institute of Geological Survey Zhengzhou 450007 China 3. state key Laboratory of Geological Processes and Mineral Resources at China University of Geo{2. Wuhan 430074 China 4. Faculty of Material sciences and chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South China, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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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,{2.,{3.,{3., 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_2. 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

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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 Laboratory of {2. {3.,{3., chinese academy of sciences, lanzhou 73.000, 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

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A Novel Dimeric Eremophilane from Ligularia virgaurea spp. oligocephala

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chinese chemical Letters 2005年第11期 61-64页

作者： Quan Xiang WU1, Xia LIU2. Yan Ping SHI1, 2.1state {3. Laboratory of Applied Organic Chemistry, {2. University, lanzhou 73.000 2.1} Laboratory for Natural Medicine of Gansu Province,{3., chinese academy of sciences, lanzhou 73.000

A novel dimeric eremophilane, ligulolide B, was isolated from the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala. The structure was elucidated by various spectroscopic methods including ... 详细信息

关键词： Ligularia virgaurea spp. oligocephala sesquiterpene dimeric eremophilane

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THE　THEORY　OF　RESONANT　AND　NONRESONANT　PUMP－PROBE　POLARIZATIONSPECTROSCOPYFORGROUND－stateCOHERENCE

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chinese chemical Letters 1996年第4期7卷 353-356页

作者： Yi ZHAO Guo Zhong HE(state key Laboratory of Molecular Reaction Dynamics, Dalian {2. of {3. {3.. chinese academy of sciences, Dalian 11602.) chinese ACAD SCI DALIAN INST CHEM PHYSSTATE KEY LAB MOL REACT DYNAMDALIAN 116023PEOPLES R CHINA

A density matrix treatment of the time evolution of the third order polarization response describing the ground state coherence induced by ultrafast pulses is given. The explicit formulas of polarization response for nonresonant and resonant excitation are derived. The results show that the signal can be greatly enhanced in case of resonance. For specification, we discuss the ground- state rotational coherence based on the if irreducible tensor algebra.

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钴氧化铝纳米有序阵列复合结构的光学特性研究

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物理学报 2004年第5期53卷 1594-1598页

作者：李燕王成伟田军刘维民陈淼力虎林西北师范大学物理与电子工程学院兰州730070 中国科学院兰州化学物理研究所固体润滑国家重点实验室兰州730000 兰州大学化学化工学院兰州730000

对采用电化学沉积工艺制备的Co AAO纳米线有序阵列复合结构的光反射和光吸收特性进行了研究 .UV VIS NIR光谱仪测试结果表明 ,增加氧化铝模板孔洞中纳米线的长度或直径 ,Co AAO纳米有序阵列复合膜的吸收边大幅度红移 (2.83. 3.8nm) ,... 详细信息

对采用电化学沉积工艺制备的Co AAO纳米线有序阵列复合结构的光反射和光吸收特性进行了研究 .UV VIS NIR光谱仪测试结果表明 ,增加氧化铝模板孔洞中纳米线的长度或直径 ,Co AAO纳米有序阵列复合膜的吸收边大幅度红移 (2.83. 3.8nm) ,可见至近红外波段反射率大范围可调 (70 %— 6 % ) ,实验发现这种变化更加敏感于直径 .这种复合结构体系具有直接带隙半导体的光学特性 .

关键词：多孔氧化铝模板吸收边调制反射率调制纳米有序阵列电化学沉积工艺直接带隙半导体

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H_2.production with low CO selectivity from photocatalytic reforming of glucose on metal/TiO_2.catalysts

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Science China Chemistry 2008年第2期51卷 97-100页

作者： WU GuoPeng1,2. CHEN Tao2. ZHOU GuoHua 2. ZONG Xu2.& LI Can2.1 Laboratory of Plasma Physical Chemistry, Dalian University of Technology, Dalian 11602., China 2.state key Laboratory of Catalysis, Dalian {2. of chemical {3., chinese academy of sciences, Dalian 11602., China Laboratory of Plasma Physical Chemistry Dalian University of TechnologyDalian 116024China state key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

H2.with low CO concentration is produced via photocatalytic reforming of glucose (as a representative of biomass component) on metal/TiO2.catalyst (metals: Pt, Rh, Ru, Ir, Au, Ni, Cu). It is shown that the loaded metals generally enhance the rate of H2.production, while they depress the CO selectivity. Both H2.production and CO selectivity are strongly dependent on the kind of deposited metals on TiO2. For example, Rh/TiO2.catalyst is found to be most active for H2.production while with the most extremely low CO concentration from the photocatalytic reforming of glucose.

关键词： photocatalysis H2 production CO selectivity glucose metal (Rh Pt Ru Ir Au Cu or Ni)/TiO2

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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, lanzhou institute of chemical physics, {2. {3. of{3., lanzhou 73.000, ChinaCorrespondence should he addressed to Jiang Zhicheng state key Laboratory 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 {3.s of Mo ions, especially Mo5+ ion (g=1.93.0} 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.

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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 Laboratory of {2. {3.,{3., chinese academy of sciences, lanzhou 73.000, 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

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Characteristics of InGaN multiple quantum well blue-violet laser diodes

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Science China(Technological sciences) 2006年第6期49卷 727-732页

作者： LI Deyao1, ZHANG Shuming1, WANG Jianfeng1, CHEN Jun1, CHEN Lianghui2. CHONG Ming2. ZHU Jianjun1, ZHAO Degang1, LIU Zongshun1, YANG Hui1 & LIANG Junwu1 1. state {3. Laboratory of Integrated Optoelectronics, {2. of Semiconductors, chinese academy of sciences, Beijing 100083. China 2. Nano-Optoelectronics Laboratory, {2. of Semiconductors, chinese academy of sciences, Beijing 100083. China state key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China Nano-Optoelectronics Laboratory Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Studies on InGaN multiple quantum well blue-violet laser diodes have been reported. Laser structures with long-period multiple quantum wells were grown by metal-organic chemical vapor deposition. Triple-axis X-ray diffraction (TAXRD) measurements show that the multiple quantum wells were high quality. Ridge waveguide laser diodes were fabricated with cleaved facet mirrors. The laser diodes lase at room temperature under a pulsed current. A threshold current density of 3.3.kA/cm[2.; a characteristic temperature T 0 of 145 K were observed for the laser diode.

关键词： metalorganic chemical vapor deposition (MOCVD), GaN-based laser diodes, multiple quantum well, ridge waveguide, threshold current.

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