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La_(0.67)Pb_(0.33)MnO_3的J-A分析

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中国稀土学报 2005年第S2期23卷 139-141页

作者：曹先胜张学梅西北第二民族学院材料系宁夏银川750021 苏州职业大学江苏苏州215011

使用固相反应法制备了La0.67Pb0.33MnO3多晶样品,为深入了解材料的磁化性质,采用J-A模型对钙钛矿La0.67Pb0.33MnO3的磁化曲线和磁滞回线的实验结果进行数值模拟和分析,数值模拟结果再现了测量结果的变化规律。并与Preisach模型模拟结论... 详细信息

使用固相反应法制备了La0.67Pb0.33MnO3多晶样品,为深入了解材料的磁化性质,采用J-A模型对钙钛矿La0.67Pb0.33MnO3的磁化曲线和磁滞回线的实验结果进行数值模拟和分析,数值模拟结果再现了测量结果的变化规律。并与Preisach模型模拟结论进行了对比。

关键词： J-A模型磁滞回线磁化曲线

Simulation of Gas-solid Two-phase Flow to Process of Filling the Foam Mould

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Simulation of Gas-solid Two-phase Flow to Process of Filling...

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Junxia JIANG1 a Zhichao WU2.b Liliang CHEN3 c state Key laboratory of {2. Processing and Die & Mould Technology Huazhong university of Science and Technology Wuhan china

In lost foam casting（LFC）,the foam pattern is the key qualification, and the filling process is one of the crucial processes to ensure the high quality of the foam pattern. Filling without uniformity and denseness will cause various defects and affect the quality of the surface. The influential factors of filling process are analyzed .And optimizing filling process, enhancing efficiency, decreasing waster are obtained by the numerical simulation of filling process using computer. The governing equations of the dense compressible gas-solid two-phase flow are established, and the physical signification of each one in the equations is discussed. The filling process is solved by Euler- Euler model. In the simulation, the volume of foam bead in every governing unit at different time is calculated, and the trend of foam bead flow is obtained. The filling process of various different conditions is simulated, considering different shooting methods and the position of baffles, and recorded by digital vidicon. The characteristics and the rules of the process are summarized. By contrasting the result of the numerical simulation with the one of examination, it is found that the fluid trend of foam bead in the numerical simulation is accordant to the actual process. So the numerical simulation of filling process by applying this model is an effective method.

关键词： lost foam casting foam pattern gas-solid two-phase flow filling process numerical simulation

solid-phase extraction of trans-resveratrol by molecularly imprinted polymers with bi-functional monomers

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Solid-phase extraction of trans-resveratrol by molecularly i...

甘肃省化学会二十六届年会暨第八届中学化学教学经验交流会

作者： Chuande Zhao~1,Rui Chen~1,Xiaoman Jiang~1,Linyuan Guo~1,Haixia Zhang~(1,2. 1 department of Chemistry,Lanzhou university,Lanzhou 730000,{2., 2.state Key laboratory of Applied Organic Chemistry,Lanzhou university,Lanzhou 730000,{2.

With methacrylic acid andβ-cyclodextrin acting functional monomers,trans-resveratrol molecularly imprinted polymers were synthesized in this *** with each other,the molecularly imprinted polymer coming from two above mentioned functional monomers has higher adsorption capacity and higher selective factor than that one produced only by methacrylic *** kinds of molecularly imprinted polymers are superior to their corresponding non-imprinted polymers in adsorption capacity and *** bi-functional monomers molecularly imprinted polymer(1) has been used as the packing material of solid phase extraction to concentrate trans-resveratrol in wine and Chinese liquor *** analytical method to determine trans-resveratrol in wine and Chinese liquor has been *** limit of detection for trans-resveratrol was 0.001μg mL.

关键词： Molecularly imprinted polymers Methacrylic acid β-cyclodextrin Trans-resveratrol solid-phase extraction High performance liquid chromatography

microstructure Characteristics and Apparent Viscosity of Hypereutectic Al-2.%Si Alloy Melt During Semi-solid {2. Stirring

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Journal of university of Science and Technology Beijing 2001年第2期8卷 126-128页

作者： Yanjun Li, Weimin Mao, Zisheng Zhen, Xueyou Zhong (material Science and Engineering School, university of Science and Technology Beijing, Beijing 100083, {2.) Univ Sci & Technol Beijing Mat Sci & Engn Sch Beijing 100083 Peoples R China

The microstructural evolution and apparent viscosity of hypereutectic Al-2.%Si alloy during semi-solid state shearing were studied with a Searte type viscometer. When the alloy melt was continuously stirred from 72. degreesC to eutectic temperature, the primary Si crystals were gradually changed from elongated platelets to near-spherical shapes. It was found that some nondendritic a-phase formed when the melt was stirred below 585 degreesC. The experiment showed that the semi-solid stirring had strong effect on inhibiting the anisotropic growth of Si crystals during solidification. The apparent viscosity of the alloy melt increased slowly with the decreasing of temperature before the formation of nondendritic alpha -phase, which caused the dramatic increase of apparent viscosity.

关键词： hypereutectic Al-Si alloy solidification structures apparent viscosity

化学共沉淀法制备的(Y_(1-x-y),Gd_y)_2._3∶xEu^(3+)红色荧光粉及其发光性能

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发光学报 2012年第3期33卷 247-252页

作者：蒲勇朱达川马明星韩涛赵聪四川大学材料科学与工程学院四川成都610065 重庆文理学院材料交叉学科研究中心重庆市高校微纳米材料工程与技术重点实验室重庆402168

用化学共沉淀法一次煅烧工艺合成了(Y1-x-y,Gdy)2.3∶xEu3+(x=0.06～0.10,y=0,0.2.～0.2.)系列红色荧光粉。用XRD、SEM和荧光分光光度计,对试样的晶体结构、表面形貌及发光性能进行表征。研究了Eu3+、Gd3+的掺杂浓度、表面活性剂的加入... 详细信息

用化学共沉淀法一次煅烧工艺合成了(Y1-x-y,Gdy)2.3∶xEu3+(x=0.06～0.10,y=0,0.2.～0.2.)系列红色荧光粉。用XRD、SEM和荧光分光光度计,对试样的晶体结构、表面形貌及发光性能进行表征。研究了Eu3+、Gd3+的掺杂浓度、表面活性剂的加入、煅烧温度对样品性能的影响。结果表明:样品为立方晶系;Gd3+的加入会使基体晶格发生畸变,晶胞参数增加,起到改善样品色纯度和发光效率的作用;最佳煅烧温度为900℃,比传统的高温固相法低500℃左右;所合成荧光粉的粒度主要分布在300～400 nm,结构比较松散;当x=0.08,y=0.2.时,最大发射峰(λem=613 nm)强度最大。所合成的Y1-x-y,Gdy)2.3∶xEu3+荧光粉是一种性能较好的PDP用红色荧光粉。

关键词： (Y1-x-y,Gdy)2.3∶xEu3+ 3D-PDP 化学共沉淀法红色荧光粉

CARBON NANOTUBE/NICKEL OXIDE COMPOSITE ELECTRODES FOR SUPERCAPACITORS

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CARBON NANOTUBE/NICKEL OXIDE COMPOSITE ELECTRODES FOR SUPERC...

第8届国际材联电子材料国际研讨会

作者： Kui Liang Ai Chen Yue LiP.O.Box 1503-2.Institute of Microelectronics & solid state Electronics {2. of Electronic Science &Technology of china Chengdu 610054

＜正＞ Carbon nanotubes （CNT）and nickel oxide（NiO） are two attractive electrode materials for supercapacitors. Carbon nanotubes may have high electric conductivity, but the way of forming capacitance of supercapacitors based on them is electric double layer capacitance and the corresponding specific capacitance is not big enough. The way of forming capacitance of supercapacitors based on nickel oxide is pseudocapacitance and the corresponding specific capacitance is rather big, but the electric conductivity of this material is too small. It is well known that the big specific capacitance and high electric conductivity are very important to a

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MAMNUFACTURE OF BaTiO3 BASED CERAMIC POWDER AND ITS PROPERTY

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MAMNUFACTURE OF BaTiO3 BASED CERAMIC POWDER AND ITS PROPERTY

第三届全国压电和声波理论及器件技术研讨会

作者： Ling WANG Amorphous and Information Composites Lab,nanjing university of Information Science & Technology, nanjing,Jiangsu 2.0044,{2. Hao-feng ZHAO department of materials,nanjing university of Information Science & Technology, nanjing,Jiangsu 2.0044,{2.

BaTiO based ceramics were applied widely to make electronics *** conventional processing of BaTiO ceramic particles relies on the solid-state reactions,by which the coarse,impure,inhomogeneous and multiphase powders were *** this paper,new method was used to synthesize BaTiO based ceramic nanopowder with the particle size 2.- 90nm by use of Ba(NO),-Ti(OCH) -ammonia-citric acid raw {2. *** equipment was used to measure the specific surface area of BaTiO based *** pacific surface area is 15 m/*** was applied to measure particle size and *** test results show that the fine BaTiO based ceramic particles were well distributed and the dielectric constant of the {2. is more than 5000.

关键词： BaTiO3 powder preparation composite dielectric constant

Determination of Estrogens and Bisphenol A in Bovine Milk by Automated on-line C30 solid-phase Extraction Coupled with High-performance Liquid Chromatography-mass Spectrometry

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Determination of Estrogens and Bisphenol A in Bovine Milk by...

第五届全国环境化学大会

作者： Wei Yan~1 Ying Li~1 Lixia Zhao~1 Jinming Lin~(1,2.*) (1 state Key laboratory of Environmental Chemistry and Ecotoxicology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,P.O.Box 2.71,Beijing 100085, {2. 2.3} of Chemistry,Tsinghua university,Beijing 100084,{2.

Using triacontyl bonded silica(C) as on-line solid-phase extraction(SPE) material and a specially designed online analytical system which allowed large sample volume injection,a high speed and robust online SPE-HPLC-MS method was established for the analysis of five estrogens and bisphenol A(BPA) in milk *** milk sample is pretreated with acetonitrile for protein precipitation and then treated with primary

关键词： Triacontyl bonded silica Estrogens Liquid chromatography-mass spectrometry Spiked milk samples

Morphology and Electrical Characteristics of(PEO)10LiCIO4Electrolyte with Nanosized CeO2

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Morphology and Electrical Characteristics of(PEO)10LiCIO4Ele...

2.11绿色建筑技术与材料国际会议

作者： De-Jiang Qi~(1,2.a),Xiao-Hong Yang~(2.b),Xiao-Guo Bi~(2.c)and Hong-Qiang Ru~(1,d) 1 School of material & Metallurgy,Northeastern university,Shenyang 110004,{2. 2.Shenyang Institute of Engineering,Shenyang 110136,{2.

In the present work,using nanosized rare earth oxide CeO as filler and acetonitrile as organic solvent,a novel solid-state composite polymer electrolyte(CPE)films(PEO)LiClO-x wt.%CeO(x=0,2.6,9,12.15)was prepared by solution-casting *** effect of CeO) filler concentration on morphology and electrical characteristics of CPE films has been investigated and *** AC impedance measurements show that the ionic conductivity of CPE can be efficiently enhanced by adding appropriate *** highest room temperature(2.℃)ionic conductivity of 1.71×10S·cmis achieved with the CeO content of 9 wt.%.With the CeO content continues to increase,CPE ionic conductivity begin to *** is because appropriate CeO can disorder the chain structure and effectively inhibit the crystallization of PEO,which expands the amorphous region required for the lithium-ion transport.

关键词： Polyethylene oxide composite polymer electrolyte nanosized CeO2 ionic conductivity