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Thermal behaviors and growth of reduced ferronickel particles in carbon-laterite composites

Rare Metals 2011年第6期30卷 681-687页

作者： HUANG Donghua ZHANG Jianliang MAO Rui CAO Mingming School of Metallurgical and Ecological Engineen＇ng State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

The thermal behaviors of single laterite ore and graphite-laterite mixtures were investigated by thermogravimetry （TG）, derivative thermogravimetry （DTG）, and differential thermal analysis （DTA）. Four mass loss steps maximized at about 78, 2.2. 583, and 82.℃ are observed for the laterite ore, representing the vaporization of free water, the dehydroxylation of goethite, the decomposition of serpentines, and the second dehydroxylation of serpentines, respectively. The reduction reactions of the graphite-laterite mixtures start at around 700℃ and can be divided into three major temperature regions. Coal-laterite composites with an addition of 10 wt.% CaO were roasted at 1100-1350℃ for 30 min, and the reduced samples were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results indi- cate that the reduction reactions proceed more completely at higher temperatures. The growth of the reduced ferronickel particles is greatly influenced by the roasting temperature, Obvious growth of the reduced ferronickel particles appears with the formation of worm-like crystals for the sample reduced at 12.0℃ and spheric particles are observed for the sample reduced at 1300℃. When the reduction temperature increases to 1350℃, the reduced ferronickel particles agglomerate to ferronickel granules of 3-8 mm in diameter. The main elements in the granules include iron, nickel, chromium, carbon, and sulfur, with the content of nickel and that of iron of 9.08 wt.% and 85.2. wt.%, respectively.

关键词： laterite ferronickel granules dehydration reduction thermal analysis

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Preparation and Characteristic of Self-regulation Water-transmitting Coating Fiber

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Journal of Wuhan university of Technology(Materials Science) 2009年第4期24卷 520-524页

作者：张增志 Research Institute of Ecological and Functional Materials China University of Mining and Technology(Beijing)

Common clay, Kaolin and Bentonite were used as additives to prepare water-transmitting coating fiber, respectively, and the water-transmitting characteristic of coating fiber was studied. Different water-transmitting coating fibers were prepared by coating fiber using coating material with different mass proportions of additives to adhesive. And the coating materials were made from three kinds of inorganic clays as additives respectively and polyvinyl alcohol （PVA） as adhesive. Furthermore, the surface morphology and water-transmitting capacity of coating fiber were studied by SEM, Perkin Elmer Diamond SII thermal multi-analyzer and instrument for quick measurement moisture M30. The experimental results indicate that water-transmitting coating fibers made from three kinds of clays all have water-transmitting capacity. The surface of water-transmitting coating fiber prepared by common clay T is continuous and compact, and the water-transmitting effect is better than coating fibers made from other clays.

关键词： self-regulation water-transmitting coating fiber storage and controlled-release film composite film inorganic clay

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Preparation and Characterization of Porous Spherical LiFePO_4.C by Spray Drying and Carbothermal Method

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Journal of Wuhan university of Technology(Materials Science) 2007年第B12期22卷 853-855页

作者：于锋张敬杰 Technical Institute of Physics and Chemistry Chinese Academy of Sciences graduate School of the Chinese academy of {2. Beijing 100049China

The porous spherical LiFePO4.C powders were prepared by spray drying and carbothermal method （SDCTM）. Cheaper trivalent iron ion was used as the precursor. The pure olivine phase can be prepared with the spray drying and subsequent heat-treatment. The average particle size is around 10μm, and the value of porosity is 63.04.. The results indicate that the initial discharge capacity decreases with increasing charge/ discharge rate and reduces from 138.8 mAh · g^-1 at C/2. rate to 98.3 mAh ·g^-1 at 2. rate, while the polarization between the charge and discharge plateaux is enlarged from 53 mv to 34. mv. However, the average discharge efficiency is up to 99.5% at 2. rate compared to 80.6% at C/2. rate from the second cycle.

关键词： LiFePO4 spherical porosity discharge efficiency spray drying and carbothermal method (SDCTM)

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Study on 3D simulation of wave fields in acoustic reflection image logging

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Science china Earth sciences 2008年第S2期51卷 186-194页

作者： TAO Guo,HE FengJiang,WANG Bing,WANG Hua & CHEN Ping State Key Laboratory of Petroleum Resources and Prospecting,china university of Petroleum,{2. 102.4.,china china Univ Petr State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China

The borehole acoustic reflection imaging logging is a newly developed acoustic logging method that has attracted many interests. These converted and reflected waves for imaging are usually mixed up with borehole guided waves and therefore difficult to be clearly identified. To improve the downhole tool design and develop more sophisticate data processing and interpretation algorithms,studies on precisely numerical modeling of the wave fields in the acoustic reflection imaging logging are neces-sary and critical. This paper developed a parallelized scheme of 3D finite difference (3DFD) with non-uniform staggered grid and PML absorbing boundary to simulate the acoustic wave fields in isotropic and anisotropic formations. Applications of this scheme to the typical cases of isotropic and anisot-ropic formations and comparison with the results from published analytical solutions have demon-strated the validation and efficiency of the scheme. Higher accuracy and lower computation cost (3.5 times faster than the conventional schemes) have been achieved with this scheme for modeling such a complex wave fields of 60 dB dynamic range with higher frequency (10 kHz). This simulating program provides a quantitative analytical means for studying acoustic reflection imaging tool and development of the data processing and interpretation methods.

关键词： acoustic reflection imaging 3D wave field modeling non-uniform staggered grid PML absorb ring boundary parallel scheme

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Ontology-based analysis of multi-scale modeling of geographical features

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Science china(Technological sciences) 2006年第z2期49卷 121-131页

作者： WANG Yanhui, LI Xiaojuan & GONG Huili Key Laboratory of Three-Dimensional Information Acquisition and Application, Ministry of Education, Capital Normal university, beijing 10003.,{2. beijing Key Laboratory of Resource Environment and GIS, Capital Normal university, beijing 10003.,{2. Capital Normal Univ Minist Educ Key Lab Dimens Informat Acquisit & Applicat 3 Beijing 100037 Peoples R China Capital Normal Univ Beijing Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing 100037 Peoples R China

As multi-scale databases based on scale series of map data are built, conceptual models are needed to define proper multi-scale representation formulas and to extract model entities and the relationships among them. However, the results of multi-scale conceptual abstraction schema may differ, according to which cognition, abstraction and application views are utilized, which presents an obvious obstacle to the reuse and sharing of spatial data. To facilitate the design of unified, common and objective abstract schema views for multi-scale spatial databases, this paper proposes an ontology-based analysis method for the multi-scale modeling of geographical features. It includes a three-layer ontology model, which serves as the framework for common multi-scale abstraction schema; an explanation of formulary abstractions accompanied by definitions of entities and their relationships at the same scale, as well as different scales,which are meant to provide strong feasibility, expansibility and speciality functions; and a case in point involving multi-scale representations of road features, to verify the method's feasibility.

关键词： multi-scale representation, ontology-based analysis, multi-scale data modeling, hierarchical ontology.

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Error estimate of the homogenization solution for elliptic problems with small periodic coefficients on L~∞(Ω)

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Science china Mathematics 2010年第5期53卷 194-215页

作者： HE WenMing1,2.& CUI JunZhi3 1Department of Mathematics,Wenzhou university,Wenzhou 32.035,china 2.chool of Aeronautics and Astronautics,Zhejiang university,Hangzhou 31002.,china 3LSEC,ICMSEC,academy of Mathematics and Systems Science,Chinese academy of sciences,beijing 100190,china 1. Department of Mathematics Wenzhou University Wenzhou 325035 China2. School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China3. LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

In this paper,we discuss the multi-scale homogenization theory for the second order elliptic problems with small periodic coefficients of the form xi(aij(xε) uεx(jx)) = f(x).Assuming n = 2.and u0 ∈ W 1,∞(Ω),we present an error estimate between the homogenization solution u0(x) and the exact solution uε(x) on the Sobolev space L∞(Ω).

关键词： multi-scale homogenization theory homogenization solution second order elliptic equations with small periodic coeficients

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Study on Agent Based Methods for Concurrency Control in CSCW

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 495-499页

作者： Li Hu, Yao Shu zhen, Liu Chang hui Department of Computer Science, beijing university of Aeronautics and Astronautics, beijing 100083, china Department of Computer Science Beijing University of Aeronautics and Astronautics Beijing 100083 China

Concurrency control is a critical technology and one of the problems in CSCW systems. With the development of agent based technology, it has also been applied to research and development of CSCW systems. An Agent based method for concurrency control in CSCW is explored in this paper. This new way is achieved by making use of the thoughts of AOP (Agent Oriented Programming) to improve traditional locking method, on the basis of researching characteristics and functional requirements of concurrency control in CSCW, and analyzing various usually used concurrency control methods. All amendments to locking method are done on the basis of the analysis of limitations brought by locking. In this paper, a new algorithm supporting queue of locking request for Agent based concurrency control is also presented. All above aspects are discussed in some detail in this paper.

关键词： CSCW agent AOP Concurrency control algorithm supporting queue of locking request

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基于柔性集成框架的分布式铁路运输仿真体系结构研究

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铁道学报 2002年第3期24卷 9-13页

作者：蒋熙杨肇夏苗建瑞谢保锋北方交通大学交通运输学院北京100044 铁道科学研究院通信信号研究所北京100081

为解决当前大规模复杂铁路运输仿真系统存在的适应性较差、集成程度较低、维护与扩充的灵活性不足等问题 ,本文探讨了复杂分布式仿真系统的构建方法 ,建立了基于柔性集成框架的铁路运输仿真开放式分布仿真体系结构 ,能面向不同仿真应用... 详细信息

为解决当前大规模复杂铁路运输仿真系统存在的适应性较差、集成程度较低、维护与扩充的灵活性不足等问题 ,本文探讨了复杂分布式仿真系统的构建方法 ,建立了基于柔性集成框架的铁路运输仿真开放式分布仿真体系结构 ,能面向不同仿真应用需求构建综合性仿真系统 ,并具有高度的灵活性、适应性。

关键词：柔性集成框架体系结构铁路运输计算机仿真系统集成分布式仿真系统

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Effect of Tempering Temperature on Microstructure and Properties of E690 Offshore Plate Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 67-72页

作者： ZHANG Jie, CAI Qing-wu, WU Hui-bin, ZHANG Kun, WU Bo (Research Institute of Metallurgy Engineering, university of Science and Technology beijing, beijing 100083, china) Research Institute of Metallurgy Engineering University of Science and Technology Beijing Beijing 100083 China

A new kind of Mn Mo Nb Cu B bainite steel which satisfied mechanical demands of E690 offshore plate steel was designed. The effect of two processes thermomechanical control process （TMCP）＋ tempering （T） and thermomechanical control process （TMCP）＋ reheating and quenching （RQ）＋ tempering （T） on microstructure and mechanical properties were studied by means of scan electron microscope （SEM）, transmission electron micro- scope （TEM） and electron back scatter diffraction （EBSD）. The results showed that optimal mechanical properties were available when tempering at 550 ℃ for both processes. The microstructure of the TMCP＋T treated sample tempering in the range of 4.0 to 550 ℃ for 1 h did not change dramatically yet the lath in the TMCP＋RQ＋T trea- ted sample merged together and transformed into polygonal ferrite. At the same time, the sub-structure of grain bainite transformed from lath to cell shape to refine grains with tempering temperature mounting. Lots of sub-grain boundaries were located within bainite and adjacent bainite grain boundaries were high angle.

关键词： offshore plate low carbon bainitic steel tempering toughness EBSD

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Embryonic stem cells generated by nuclear transfer of human somatic nuclei into rabbit oocytes

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Cell Research 2003年第4期13卷 251-263页

作者： YING CHEN, ZHI Xu HE, AILIAN LIU, KAI WANG, WEN WEI MAO, JIAN XIN CHU, YONG LU, ZHENG Fu FANG, YING TANG SHI, QING ZHANG YANG, DA YUAN CHEN, MIN RANG WANG, JIN SONG LI, SHAO LIANG HUANG, XIANG YIN KONG, YAO ZHOU SHI, Zm QIANG WANG, JIA HuI XIA, ZHI GAO LONG, ZHI GANG XUE, WEN XIANG DING, HuI ZHEN SHENG Center for Developmental Biology, Shanghai Second Medical university, Shanghai 2.0092. china Laboratory of Stem Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological {2., Chinese academy of {2., 1665 Kong Jiang Road, Shanghai 2.0092. china Center for Stem Cell Research, the Second Affiliated Hospital, Sun Yat-Sen university, Guangzhou 51012.,china State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese academy of {2., 19 Zhong-guan Cun Road, Haidian District, beijing 100080, china Health Science Center, Shanghai Institutes of Biological {2., Chinese academy of {2. and Shanghai Second Medical university, Shanghai 2.002., china National Laboratory of Medical Genetics, Central South university, 88 Xiangya Road, Changsha 4.0078, china Xinhua Hospital, Shanghai Second Medical university, 1665 Kong Jiang Road, Shanghai 2.0092. china 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 3Center for Stem Cell Research the Second Affiliated Hospital Sun Yat-Sen University Guangzhou 510120 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 2.aboratory of Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 1665 Kong Jiang Road Shanghai 200092 China. 4.tate Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences 19 Zhong-guan Cun Road Haidian District Beijing 10008

To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the transfer of human somatic nuclei into rabbit oocytes. The number of blastocysts that developed from the fused nuclear transfer was comparable among nuclear donors at ages of 5, 4.0} 52.and 60 years, and nuclear transfer (NT) embryonic stem cells (ntES cells) were subsequently derived from each of the four age groups. These results suggest that human somatic nuclei can form ntES cells independent of the age of the donor. The derived ntES cells are human based on karyotype, isogenicity, in situ hybridization, PCR and immunocytochemistry with probes that distinguish between the various species. The ntES cells maintain the capability of sustained growth in an undifferentiated state, and form embryoid bodies, which, on further induction, give rise to cell types such as neuron and muscle, as well

关键词： nuclear transfer (NT) somatic cell nuclear transfer (SCNT) embryonic stem cells (ES cell) therapeutic cloning rabbit oocyte.

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