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Preparation and Electrocatalytic Activity of Polyaniline-poly (Propylene Oxide) Modified by Pt Nanoparticles

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Journal of Wuhan University of Technology(Materials science) 2006年第4期21卷 9-11页

作者：李美超 College of Chemical Engineering and Material science State Key Laboratory Breeding Base of Green Chemistry-Synthesis TechnologyZhejiang University of TechnologyHangzhou 310032China

The preparation and electrocatalytic activity of polyaniline-poly （ propylene oxide ）（ PAN-PPO ） modified by Pt particles （ Pt/ PAN-PPO ） were investigated. Pt/ PAN-PPO was characterized by scanning electron microscopy （SEM） and energy dispersive spectroscopy （ EDS ）. Pt particles on PAN-PPO were in the nanometer range, and dispersed in a three-dimensional distribution on the surface of PAN-PPO film. Compared with polyaniline and glassy carbon modified with Pt particles under the same conditions, Pt/PAN-PPO exhibited a high electrocatalytic activity for lysine oxidation.

关键词： aniline propylene oxide copolymer platinum electrocatalytic activity lysine

Large-scale information entropy analysis of important sites in mature and precursor miRNA sequences

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science china(Life sciences) 2009年第8期52卷 771-779页

作者： DU JiangFeng1,2,WU YongJun2,ZHANG YinXia3,WU Lei1,2,WANG XiaoLong3,TAO ShiHeng1,2 1 Bioinformatics Center,Northwest science and Technology University of Agriculture,Yangling 712100,china 2 College of Life sciences,Northwest science and Technology University,Yangling 712100,china 3 College of science,Northwest science and Technology University,Yangling 712100,china Bioinformatics Center Northwest Science and Technology University of Agriculture Yangling China College of Life sciences Northwest Science and Technology University Yangling China College of science Northwest Science and Technology University Yangling China

In order to find evidence of consistent sequence conservation or the base correlation degree in miRNA,some important sites in the sequences of reported miRNA and their precursors(pre-miRNA) were investigated via information entropy *** different groups of sites were obtained from special locations(head,tail) in miRNAs of different sources according to taxonomy(animal,plant and virus) and then analyzed by measuring the single base information redundancy(D1(L)) and the adjacent base related information redundancy(D2(L)).The results showed that D2(L) has more information than D1(L),though D1(L) changes roughly consistently with D2(L) in each *** pre-miRNAs are more conservative than those belonging to animals or *** addition,U is dominant in most sites compared with other *** was also found that in the middle of several groups,there were sites where miRNAs were cut down from pre-miRNAs by Enzyme Dicer which were significantly *** phenomenon shows that the conservatism is an aspect of the of miRNA and may be involved in the recognition and cutting by the *** results provided another perspective for understanding more about the primary structure of pre-miRNA.

关键词： miRNA conservative information entropy precursor evolution base correlation degree

SHRIMP zircon U-Pb age and significance of Early Paleozoic volcanic rocks in East Kunlun orogenic belt, Qinghai Province, china

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science china Earth sciences 2006年第1期49卷 88-96页

作者： ZHU Yunhai1, LIN Qixiang1, JIA Chunxing2 & WANG Guocan1 1.Faculty of Earth science, china University of Geosciences, Wuhan 430074, china 2.Regional Geological Survey Academy of Qinghai, Xining 800003, china Faculty of Earth science China University of Geosciences Wuhan China Regional Geological Survey Academy of Qinghai Xining China

Early Paleozoic volcanic rocks in Nuomuhong area occurred as basalt slice and meta-volcanic slice. SHRIMP zircon U-Pb dating of the basalt slice and the meta-volcanic slice show that the age of the basalt slice is 419±5 Ma, and that of the meta-volcanic slice is 401± 6 Ma. These ages directly testify that there existed Early Paleozoic ocean-continent transform in East Kunlun, the basalt slice was formed in an extensional mid-ocean ridge setting and the meta-volcanic rock slice was formed in an extrusion subduction and collision setting. The inherited zircon age of 1734 Ma in volcanic rocks reflects that the base of East Kunlun may be Middle Proterozoic.

关键词： volcanic rocks, SHRIMP zircon U-Pb age, Early Paleozoic, East Kunlun orogenic belt.

Origin of tectonic stresses in the Chinese continent and adjacent areas

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science china Earth sciences 2007年第1期50卷 67-74页

作者： ZHU ShouBiao1,2& SHI YaoLin3 1 institute of Crustal Dynamics, china earthquake administration, Beijing 100085, china 2 Department of Geophysics, Peking University, Beijing 100871, china 3 Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of sciences, Beijing 100049, china institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China Department of Geophysics Peking University Beijing 100871 China Laboratory of Computational Geodynamics Graduate University of Chinese Academy of Sciences Beijing 100049 China

based on data of principal stress orientation from focal mechanism and of geological features in china, we made pseudo-3D genetic algorithm finite element (GA-FEM) inversion to investigate the main forces acting on the Chinese continent and adjacent areas which form the Chinese tectonic stress field. The results confirm that plate boundary forces play the dominant role in forming the stress field in china, as noticed by many previous researchers. However, we also find that topographic spreading forces, as well as basal drag forces of the lower crust to the upper crust, make significant contribution to stresses in regional scale. Forces acting on the Chinese continent can be outlined as follows: the collision of the India plate to the NNE is the most important action, whereby forces oriented to the NW by the Philippine plate and forces oriented to the SWW by the Pacific plate are also important. Topographic spreading forces are not negligible at high topographic gradient zones, these forces are perpendicular to edges of the Tibetan Plateau and a topographic gradient belt running in the NNE direction across Eastern china. Basal drag forces applied by the ductile flow of the lower crust to the base of upper crust affect the regional stress field in the Tibetan Plateau remarkably, producing the clockwise rotation around the eastern Himalaya syntax.

关键词： genetic algorithm finite element method topographic spreading forces ductile lower crust Chinese continent.

Energy dispersion of complex non-isolated vortices

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Chinese science Bulletin 2011年第25期56卷 2713-2717页

作者： LUO ZheXian 1,2 1 Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information science and Technology, Nanjing 210044, china 2 Wuxi Research Center of Environmental science and Technology, Wuxi 214031, china Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Nanjing China Wuxi Research Center of Environmental science and Technology Wuxi China

Energy dispersion is a fundamental scientific problem in the study of natural disasters such as typhoons, heavy rain and earthquakes. The problem has been addressed by both multi-discipline research and forecast studies. The dynamics of isolated circular vortex energy dispersion have been solved. However, the disastrous results of typhoons and heavy rain often occur due to non-isolated circular vortices, the dynamics of which are explored in this paper. The energy dispersion characteristics of non-isolated vortices with complex structural patterns are examined using a linearized nondivergent barotropical vorticity equation model. In the initial field, a tropical cyclone (TC) vortex and a meso-scale vortex coexist, forming a complex structural pattern. An analytic solution based on a Fourier transform and simulations using a two-dimensional model show the following. (1) A wave train of TC-G-D may be created by the energy dispersion where the line connecting the three member centers of the wave train is parallel to the x axis in the case of an initial TC vortex without a meso-scale vortex. (2) A wave train of TC-G-D may also be created by energy dispersion. However, the line connecting the three member centers of the wave train would no longer be parallel to the x axis. Instead, they would form a triangle in the presence of the initial TC vortex with the meso-scale vortex. (3) There is a nonlinear relationship between the initial intensity of the meso-scale vortex and the base angle of the triangle. These results have the potential to be applied in the field of typhoon forecasting.

关键词：能量色散非隔离式旋涡非线性关系中尺度涡台风预报结构模式傅立叶变换

Synthesis and thermodynamic analysis of nano-La2O3

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Progress in Natural science:Materials International 2007年第7期17卷 838-844页

作者： Liu Lili~(1,2) Tang Jie~2 Li Yuxiang~1 Zhang Mei~(1**) Wang Xidong~(1,3) (1.Department of Physical Chemistry,University of science and Technology Beijing,Beijing 100083,china 2.National institute for Materials science,Segen 1-2-1,Tsukuba 305-0047,Japan 3.College of Engineering,Beijing University,Beijing 100871,china) Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 China National institute for Materials science Segen 1-2-1 Tsukuba 305-0047 Japan College of Engineering Beijing University Beijing 100871 China

The thermodynamic parameters of La（NO3）3and La（OH）3are evaluated and the thermodynamics of nano-La2O3syn- thetic process is *** the base of thermodynamic analysis,La2O3nano-powders are prepared by the sol-gel method and the experi- ment scheme is designed by an orthogonal *** dry-gelatin is analyzed with differential thermal analysis/thermo-gravimetric analy- sis（TGA-DTA）and X-ray diffraction *** microstructure of nano-La2O3powders is observed by transmission dectron micro- *** synthetic parameters affecting the average grain size and dispersivity of nano-La2O3particles are experimentally examined and *** the results indicate that nano-La2O3particles well-dispersed are obtained and the average grain size is in the range of 20—50 nm.

关键词： nano-La2O3 sol-gel thermodynamic analysis

Metal Transfer of Twin-wire Indirect Arc Argon Welding

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稀有金属材料与工程 2011年第S3期40卷 156-159页

作者： Cao Meiqing1, Zou Zengda2, Zhang Shunshan2, Qu Shiyao2 1Shandong University of science and Technology, Qingdao 266510, china 2Shandong University, Jinan 250061, china Shandong Univ Sci & Technol Sch Mat Sci & Engn Qingdao 266510 Peoples R China Shandong Univ Jinan 250061 Peoples R China

Metal transfer of twin-wire indirect arc argon welding was investigated with high speed camcorder system based on a xenon lamp source and digital oscillograph, forces on droplet were analyzed in this paper. Results show metal transfer mode that of anodal and cathodal is not completely the same. It was divided into seven types of transfer mode; spray transfer and spray-projected transfer are the important transfer mode. The base-plate was melted by energy that of the arc and drop carrying, the drop transfer direction is different from that of the current flow, anodal and cathodal drop transfer at the same time, only the frequence and size are different.

关键词： indirect arc metal transfer short circuiting transfer transfer mode

Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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science china Earth sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1 & CHEN Ronghua2 1. State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 2. The Key Laboratory of Submarine Geoscience, State Oceanic administration, Hangzhou 310012, china Tongji University State Oceanic administration

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2) and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1 and Dansgaard-Oeschger1events, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1, c2, d, e1 and e2, respectively, corresponding to oxygen isotopic 2.0, 3.1, 3.3, 4.0, 5.1 and 5.3, are identified from Core B2-9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2 and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

Discovery of sponge body fossils from the late Meishucunian (Cambrian) at Jinsha, Guizhou, south china

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Progress in Natural science:Materials International 2005年第8期15卷 708-712页

作者： YANG Xinglian 1,2*, ZHAO Yuanlong2, WANG Yue2 and WANG Pingli2(1. Nanjing institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 210008, china 2. institute of Resource and Environment, Guizhou University, Guiyang 550003, china) Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China institute of Resource and Environment Guizhou University Guiyang 550003 China

Here we report discovery of a sponge body fossil Triticispongia sp. from the base of lower Cambrian Niutitang Formation at Jinsha, Guizhou. Stratigraphically, the fossil horizon is located below Ni-Mo ore layer with the Niutitang Biota above, and is equivalent to the late Meishucunian. The species is global in shape with skeletons composed of stauractins and monaxons. Triticispongia sp. reported here may be the earliest sponge body fossils of Cambrian, which provides new information for understanding early evolution and radiation of sponge animals.

关键词： sponges Cambrian Niutitang Formation Guizhou china.