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science China Mathematics 2010年第10期53卷 2679-2696页

作者： YANG JiMing1,& CHEN YanPing2 1college of science,Hunan Institute of Engineering,Xiangtan 411104,China 2School of Mathematical sciences,South China Normal University,Guangzhou 510631,China college of science Hunan Institute of Engineering Xiangtan China School of Mathematical sciences South China Normal University Guangzhou China

A kind of compressible miscible displacement problems which include molecular diffusion and dispersion in porous media are investigated.A symmetric interior penalty discontinuous Galerkin (SIPG) method is applied to the coupled system of flow and *** the induction hypotheses instead of the cut-off operator and the interpolation projection properties,a priori hp error estimates are *** error bounds in L2(H1) norm for concentration and in L∞(L2) norm for velocity are optimal in h and suboptimal in p with a loss of power 1/2.

关键词： a priori error discontinuous Galerkin compressible miscible displacement coupled system

Effect of surface nanocrystallization on the corrosion behavior of Zircaloy-4

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science China(Technological sciences) 2009年第8期52卷 2227-2231页

作者： ZHU YuTao1,2 & ZHANG XiYan1,2,3 1 college of Materials science and Engineering, Chongqing University, Chongqing 400045, China 2 National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China 3 School of Physical science and Engineering Technology, Guangxi University, Nanning 530004, China college of Materials science and Engineering Chongqing University Chongqing China National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing China School of Physical science and Engineering Technology Guangxi University Nanning China

The contrastive corrosion experiments between surface nanocrystallined Zircaloy-4 and coarse-grained Zircaloy-4 under the condition of 673 K/10.3 MPa in pure water are carried out, and the microstructure of oxide films has been studied. The results indicate that the growth rate of oxide films formed on the nanocrystalline Zircaloy-4 is lower than that of oxide films formed on the coarse-grained Zircaloy-4. Simultaneously, the oxide/metal interface of the former is more regular and glossy than that of the latter. For nanocrystalline Zircaloy-4, the low oxygen diffusion rate through the oxide/metal interface can hinder the reaction of oxygen ion with metal ion. Furthermore, more tetragonal ZrO2 are observed in the oxide films, which can delay the martensite phase transition from tetragonal to monoclinic phase in oxide films.

关键词： nanocrystalline Zircaloy oxide film microstructure

Preparation and characterization of CoFe_2O_4/TiO_2 magnetic composite films

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science China Chemistry 2008年第9期51卷 842-847页

作者： TIAN XiaoXia1, QU ShaoBo1,2, PEI ZhiBin1 & WANG BinKe1,2 1 college of science, Air Force Engineering University, Xi’an 710051, China 2 Electronic Materials Research Laboratory, Key Laboratory of Ministry of Education, Xi’an Jiaotong University, Xi’an 710049, China college of science Air Force Engineering University Xi’an China Electronic Materials Research Laboratory Key Laboratory of Ministry of Education Xi’an Jiaotong University Xi’an China

CoFe2O4/TiO2 magnetic composite films were prepared using the sol-gel method with tetrabutyltitanate and metallic chlorates as starting materials. The effects of heat treatment temperatures on micro- structures and on magnetic properties were studied. The microstructure and properties of the samples at different heat treatment temperatures were characterized by X-ray diffraction, Raman spectrum, scanning electron microscopy, polarized microscopy and vibrating sample magnetometry. The results show that crystals of different substances grow up independently. Cobalt ferrite is evenly embedded into the titanium dioxide matrix in the prepared composite films. The magnetism of the composite films is enhanced with an increase of the heat temperature.

关键词： CoFe2O4/TiO2 composite films magnetism sol-gel

Identification of yak lactate dehydrogenase B gene variants by gene cloning

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science China(Life sciences) 2008年第5期51卷 430-434页

作者： ZHENG YuCai1, ZHAO XingBo2, ZHOU Jing1, PIAO Ying1, JIN SuYu1, HE QingHua1, HONG Jian1, LI Ning2 & WU ChangXin2 1 college of Life science and Technology, Southwest University for Nationalities, Chengdu 610041, China 2 State Key Laboratory for Agrobiotechnology and Ministry of Agriculture Key Laboratory of Animal Genetics and Breeding, college of Animal science and Technology, China Agricultural University, Beijing 100094, China college of Life science and Technology Southwest University for Nationalities Chengdu China State Key Laboratory for Agrobiotechnology and Ministry of Agriculture Key Laboratory of Animal Genetics and Breeding College of Animal Science and Technology China Agricultural University Beijing China

Native polyacrylamide gel electrophoresis showed that two types of lactate dehydrogenase (LDH) existed in yaks. Based on the electrophoresis characteristics of LDH isoenzymes, yak LDH variants were speculated to be the gene mutation on H subunit encoded by B gene. According to the mobility in electrophoresis, the fast-band LDH type was named LDH-Hf and the slow-band LDH type LDH-Hs. In order to reveal the gene alteration in yak LDH variants, total RNA was extracted from heart tissues of yaks with different LDH variants, and cDNAs of the two variants were reverse transcripted. Two variants of B genes were cloned by RT-PCR. Sequence analysis revealed that four nucleotides differed between LDH-Bf and LDH-Bs, which resulted in two amino acids alteration. By Deepview software analysis of the conformation of yak LDH1 variants and H subunit, these four nucleotides altered two amino acids that generated new hydrogen bonds to change the hydrogen bonds network, and further caused subtle conformational changes between the two LDH variants.

关键词： yak lactate dehydrogenase genetic variants gene cloning molecular modeling

High resolution stalagmite δ18O records over the past 1000 years from Dongge Cave in Guizhou

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science Bulletin 2005年第10期50卷 1003-1008页

作者： HE Yaoqi1, WANG Yongjin1, KONG Xinggong1 & CHENG Hai2 1. college of Geography science, Nanjing Normal University, Nanjing 210097, China 2. Department of Geology and Geophysics, Minnesota University, Mineapolis MN 55455, USA college of Geography science Nanjing Normal University Nanjing China Department of Geology and Geophysics Minnesota University Mineapolis USA

Based on MC-ICP-MS U-series dating and stable O-isotope analysis results, a 4―5 years resolution monsoon record over the past 1000 years has been estab- lished for two stalagmites from Dongge Cave, Guizhou. The high resolution oxygen isotope record serves as a proxy for variations in rainfall of Asian southwest monsoon over the Yunnan-Guizhou Plateau. A close relation of the δ 18O record with the ?14C record from tree rings largely reflects impact of centennial-scale solar activity on the monsoon climate changes. The conspicuous decrease in the δ 18O value at AD 1720 indicates an abrupt increase in monsoon rainfall, sug- gesting that an atmospheric-oceanic couple over the tropical Indian Ocean plays an important role in rapid increase of the Northern Hemisphere temperature over the last century.

关键词： cave stalagmite oxygen isotope southwest monsoon solar activity Guizhou.

Activity and Structure of Calcined Coal Gangue

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Journal of Wuhan University of Technology(Materials science) 2007年第4期22卷 749-753页

作者：宫晨琛李东旭 college of Materials science and Engineering Nanjing University of Technology

Coal gangue was activated by means of calcination in seven temperature ranges. Systematic research was made about activation mechanism and structural evolution. Glycerin-ethanol method, SEM, M1P and XRD were used to determine the variation of structure and activation of coal gangue during the calcination. The experimental results show that because of heat treatment in the range of calcination temperature, mineral composition and microstructure of coal gangue are changed. In addition, its activity is improved evidently. The amount of lime absorbed by the sample calcined at 700 ℃ is 2-4 times that by uncalcined coal gangue in the course of hydration. When NaOH is added to coal gangue-lime system, hydration reaction of the system is sped up and the microstructure of hydrating samples of coal gangue is improved.

关键词： coal gangue calcination activation

Uniform Attractors for a Non-Autonomous Brinkman-Forchheimer Equation

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Journal of Mathematical Research with Applications 2012年第1期32卷 63-75页

作者： Xue Li SONG 1,,Yan Ren HOU 2 1.college of science,Xi'an University of science and Technology,Shaanxi 710054,P.R.China 2.college of science,Xi'an Jiaotong University,Shaanxi 710049,P.R.China college of science Xi'an University of Science and Technology Shaanxi 710054 college of science Xi'an Jiaotong University Shaanxi 710049

This paper is concerned with the three-dimensional non-autonomous BrinkmanForchheimer *** Galerkin approximation method,we give the existence and uniqueness of weak solutions for non-autonomous Brinkman-Forchheimer *** we investigate the asymptotic behavior of the weak solution,the existence and structures of the(H,H)-uniform attractor and(H,V)-uniform *** we prove that an L 2-uniform attractor is actually an H 1-uniform attractor.

关键词： Galerkin approximation uniform attractor non-autonomous Brinkman-Forchheimer equation.

Synthesis of iron(Ⅲ)-doped nanostructure TiO_2/SiO_2 and their photocatalytic activity

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Rare Metals 2007年第6期26卷 565-571页

作者： CHEN Rufen ZHANG Lei SONG Xiuqin WEI YU HOU Denglu college of Chemistry and Material science Hebei Normal University Shijiazhuang Hebei 050016 China Key Laboralory of Advanced Film of Hebei Province Shijiazhuang Hebei 050016 China

Iron（Ⅲ）-doped nanostructure TiO2-coated SiO2 （TiO2/SiO2） particles were prepared using the layer-by-layer assembly technique and their photocatalytic property was studied. TiO2 colloids were synthesized employing the sol-gel method with TiChas a precursor. The samples were characterized by Fourier transform infrared spectroscopy （FTIR）, SEM, EDS, XPS, and XRD. The experimental results show that TiO2 nanopowders on the surface of SiO2 particles are well distributed, the amount of TiO2 is increased with the adding of coating layers, the pure anatase-TiO2 coating layers are synthesized at 500℃, and the photocatalytic activity of Fe^3＋-doped TiO2/SiO2 is higher than that of undoped TiO2/SiO2.

关键词： TiO2 coating SiO2 particle nanostructure layer-by-layer assembly doping photocatalytic activity

Application of vertically integrated sampling approach to study of new production via ^(234)Th -^(238)U disequilibria

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Acta Oceanologica Sinica 2000年第2期19卷 37-44页

作者： Chen Feizhou1 Huang Yipu2 Chen Min2 (1. college of Fishery science, Shanghai Fisheries University, Shanghai 200090, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) college of Fishery science Shanghai Fisheries University Shanghai 200090 China

The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~234Th/ ~238U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~234Th and the residence times for dissolved and particulate ~234Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(234)Th - ^(238)U disequilibria in large spatial scale.

关键词： New production vertically integrated Sampling approach, ^(234)Th - ^(238)U disequilibria Xia men Bay northern South China Sea

A New Navigation Strategy in Hypermedia Integral Ware Authoring System

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计算机工程 2002年第S1期28卷 141-144页

作者： FU Xianping1 , JIANG Jianping2(1. college of Computer science and Technology, Dalian Maritime University, Dalian 116026,China 2. college of Information Engineering, Dalian Maritime University, Dalian 116026,China ) college of Computer science and Technology Dalian Maritime University Dalian 116026China college of Information Engineering Dalian Maritime University Dalian 116026China

After analyzing the general navigation mechanisms and discussing the knowledge point card linking model which is the base of the navigation mechanism used in the Hypermedia Integral ware Authoring System(HIAS), the pa... 详细信息

关键词： Hypermedia Integral ware Navigation strategy