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Journal of materials Science & Technology 2010年第2期26卷 151-155页

作者： Zhenya zhang, Huashun Yu , Shaoqing Wang, Haitao Wang and Guanghui Min key laboratory of Liquid Structure and Heredity of materials, Ministry of Education, Shandong University, Jinan 250061, China [a] key laboratory of Liquid Structure and Heredity of materials Ministry of Education Shandong University Jinan 250061 China

This study investigated the microstructures and mechanical properties of ZK60 alloy prepared by a simplified rapid solidification powder metallurgy （RS P/M） processing system （S-RS P/M）, which consists of warm press in dry air and hot extrusion. Microstructure characterizations showed that S-RS P/M alloy consisted of magnesium matrix and oxide stringers of ~1 #m in width. TEM （transmission electron microscopy） observations illustrated nano-size magnesia particles （10-30 nm） constituted oxide stringer in detail. Due to a relatively higher volume of nano-size magnesia particle produced during S-RS P/M process, 0.2% yield strength of S-RS P/M ZKO0 alloy was found to be as high as 382 MPa, which is 10% higher than that of RS P/M alloy. The improvement in mechanical properties is mainly attributed to the combination effects of Orowan mechanism and coefficient of thermal expansion （CTE） mismatch because of the approximately same average grain size.

关键词： Microstructure Mechanical properties Rapid solidification powder metallurgy Nano-size magnesia

Giant Magnetostrictions of Tb-Dy-Fe Polycrystals with < 110 > Axial Alignment

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Journal of materials Science & Technology 2000年第2期16卷 175-176页

作者： Shouzeng ZHOU, Xuexu GAO, Maocai zhang, Qing ZHAO and Zhenhlla SHI (State key laboratory for Advanced Metals and materials, University of Science and Technology Beijing, Beijing 100083, China) State key laboratory for Advanced Metals and materials University of Science and Technology Beijing Beijing 100083 China

Preparing method and processing of Tb-Dy-Fe alloy samples with [110] axial orientation as well as their magnetostrictive properties have been studied. It has been found that the magnetostrictive strains of polycrystal samples with [110] axial orientation can reach (1550-1900) ×10~-6 in a low magnetic field less than 80 kA/m, which are equal to or somewhat better than that of the polycrystal samples with [112] axial orientation.

关键词： 110 Giant Magnetostrictions of Tb-Dy-Fe Polycrystals with Axial Alignment Fe Dy

Size-controlled and large-scale synthesis of organic-soluble Ag nanocrystals in water and their formation mechanism

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Progress in Natural Science:materials International 2011年第6期21卷 447-454页

作者： Yu-yuan SHI,Bin SUN,Zhe ZHOU,Yong-tao WU,Mei-fang ZHU State key laboratory for Modification of Chemical Fibers and polymer materials, College of Material Science and Engineering,Donghua University,Shanghai 201620,China State key laboratory for Modification of Chemical Fibers and polymer materials College of Material Science and Engineering Donghua University Shanghai 201620 China

Organic-soluble Ag nanocrystals(NCs) with tunable sizes in the range from 5.4 to 22.1 nm were synthesized by a facile, reproducible and easily scaled up route using water as solvent in the presence of oleic acid and an *** synthetic Ag NCs exhibits excellent hydrophobicity and can be well re-dispersed in various non- or weak-polar *** tunable sizes of the Ag NCs were achieved by simply adjusting the initial precursor ***-scale synthesis of the Ag NCs was realized at a high AgNO3concentration(0.4 mol/L).As much as 16.2 g highly uniform organic-soluble Ag NCs with 5 nm average diameter can be readily synthesized at low cost in a single reaction only using 400 mL water as solvent,which is adaptable to the industrial scale *** structure of the obtained Ag NCs was investigated in detail by X-ray diffractometry,transmission electron microscopy,Fourier transform infrared and thermal gravimetric analysis *** results reveal that the surface of the organic-soluble Ag NCs is coated with the monolayer surfactants consisting of oleic acid and the *** addition,on the basis of the sufficient evidences,a proposed mechanism based on the "bilayer surfactant-controlled reaction" successfully demonstrates the formation of high quality organic-soluble Ag NCs in the aqueous solution.

关键词： organic-soluble Ag nanocrystals large-scale size-controlled synthesis formation mechanism

Ionomer Toughened Polyolefine

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Journal of materials Science & Technology 1995年第6期11卷 391-397页

作者： Xi XU Xiangshen ZENG Shaoyun GUO and Huilin LI (polymer Research Institute and the State key laboratory of polymer materials Engineering,Chengdu Uuiversity of Science and Technology, Chengdu, 610065, China)

The morphology and properties of HDPE blends with Zn-SEPDM and GR were studied through SEM and mechanical property test. The results show that as Zn-SEPDM/GR content amounts to 20%, the blend becomes an IPN in structure, and that a rather high impact and tensile strength of HDPE may be obtained after blending. The antistatic effect, the softening point,and HDT of the blend are higher as compared to HDPE/Zn-SEPDM/ZnSt (zinc stearate).The effect of Zn-SEPDM on the compatibility the morphology and properties of IPP blends were studied by DSC, TEM and mechanical properties test. The results show that as Zn-SEPDM content exceeds 20%. Zn-SEPDM in the blend becomes continuous and an abrupt change in impact strength is incurred there from. Owing to the incorporation of ionic groups into *** strong interactions betWeen the chains make both the impact and the tensile strength of IPP remarkably higher

关键词： Zn EPDM HDPE PP GR Ionomer Toughened Polyolefine

CATALYSIS OF POLYSTYRENE N-HYDROXYL SULFONAMIDE FOR ESTERIFICATION OF BUTANOL WITH ACETIC ANHYDRIDE

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Chinese Journal of Reactive polymers 2004年第Z1期 1-6页

作者： LI Shufeng LI Qian YANG Xinlin HUANG Wenqiang** State key laboratory of functional polymer materials for Adsorption and Separation Institute of polymer Chemistry, Nankai University, Tianjin 300071, China

Polystyrene N-hydroxyl sulfonamide resin 1 was prepared and used to catalyze the esterification of n-butanol and acetic anhydride. The mechanism of catalytic esterification proved by IR spectra of the resins was found that O-H and N-H of the N-hydroxyl sulfonamide resin reacted with the acetic anhydride respectively to form the active intermediate polystyrene N,O-diacetyl sulfonamate which was cleaved by n-butanol to produce butyl acetate. The catalytic esterification by resin 1 was in good agreement with the kinetic model of 揵i-bi-ping-pong?mechanism.

关键词： Polystyrene N-hydroxyl sulfonamide N,O-diacetyl sulfonamate Esterification kinetics Acyl transfer.

SYNTHESIS OF THE COMPLEXES OF MACROPOROUS SULFONATED RESINS WITH FERRIC CHLORIDE ANDTHEIR CATALYTIC BEHAVIOR FOR ESTERIFICATION OF ACETIC ACID WITH BUTANOL

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Chinese Journal of Reactive polymers 1997年第1期6卷 54-60页

作者： Huang Wenqiang Hou Xin Li Chenxi HeBinglin (State key laboratory of functional polymer materials for Adsorption and Separation, Nankai University, Tianjin, China 300071)

The complex resins prepared from macroporous sulfonated resin D72 (H+ form)with ferric chloride or ferric chloride hexahydrate have both sites of Bronsted acid and Lewis acid. acid. In the catalysis of exterification of acetic acid with butanol the complex resins show to have much higher catalytic activity than that of its matrix, a conventional sulfonated cation exchange resin D72.

关键词：树脂合成乙酸丁醇

Eutectic Solidification in Al-13.0%Si Alloys with Combined Addition of Strontium and Boron

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Journal of materials Science & Technology 2009年第4期25卷 437-440页

作者： Hengcheng Liao,Ke Ding,Juanjuan Bi,Min zhang,Huipin Wang and Lei Zhao School of materials Science and Engineering,Southeast University,Nanjing 211198,China Jiangsu key laboratory for Advanced Metallic materials,Nanjing 211189,China SE Univ Sch Mat Sci & Engn Nanjing 211198 Peoples R China

The influence of addition of boron （B） on eutectic solidification in a near-eutectic Al-13.0%Si alloy modified with strontium （Sr） was investigated using thermal analysis and macro/microstructure observation. Addition of B in the Sr-modified alloy leads to a considerable increase in nucleation temperature （TN, the minimum temperature prior to recalescence （TM） and growth temperature （To）. In the Sr-modified alloy, nucleation of eutectic might originate at the heterogeneous sites on the mold wall or in the melt near the wall, and eutectic solidification proceeds gradually towards the center, controlled by undercooling of melt. However, with addition of B in the Sr-modified alloy, undercooling required for eutectic nucleation became small, and hence eutectic solidification might occur almost simultaneously within whole casting, controlled by amount of heterogeneous sites. With excessive addition of B in the Sr-modified alloy, nucleation of eutectic grains was explosive within the whole casting and the power of Sr on eutectic solidification was completely poisoned.

关键词： Al-Si alloys Solidification Microstructure Thermal analysis

Stress-Induced Precipitation of Fineγ'-Phase and Thermodynamics Analysis

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Journal of materials Science & Technology 2001年第2期17卷 257-259页

作者： Sugui TIAN Department of materials Science and Engineering, Shenyang Polytechnic University, Shenyang 110023, China Jinghua zhang, Yongbo XU and Zhuangqi HU State key laboratory for Fatigue and Fracture of materials, Institute of Metal Research, Chinese Shenyang Polytech Univ Dept Mat Sci & Engn Shenyang 110023 Peoples R China Chinese Acad Sci Inst Met Res State Key Lab Fatigue & Fracture Mat Shenyang 110015 Peoples R China Northeastern Univ Shenyang 110006 Peoples R China

The microstructures of a single crystal Ni-base superalloy with [001] orientation were observed by means of TEM. Results showed that the fine γ' particles were precipitated in the γ matrix channels during the tensile deformation of the alloy. Thermodynamics analysis indicated that the solubility of elements M(Al,Ta) within the γ matrix may be changed when the alloy was deformed by the external applied stress. The tensile stress reduced the solubility of elements Al and Ta so as to occur the over-saturation and agglomeration of them, which promoted the precipitation of fine γ'-phase in the γ matrix.

关键词： In Phase and Thermodynamics Analysis Stress-Induced Precipitation of Fine Ta

Crystal Pattern Formation and Transitions of PEO Monolayers on Solid Substrates from Nonequilibrium to Near Equilibrium

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Crystal Pattern Formation and Transitions of PEO Monolayers ...

Improvement of sensitivity of graphene photodetector by creating bandgap structure

2006年海峡两岸高分子学术研讨会

作者： Wei Wang , Xuemei Zhai, Guoliang zhang, Binglin He The key laboratory of functional polymer materials of Ministry of Education and Institute of polymer Chemistry, Nankai University, Tianjin 300071

＜正＞The crystal pattern formation and transition of the monolayers of a low-molecular-weight poly（ethylene oxide）（Mn = 5000 g/mol） on the surface of silicon wafer were studied using atomic force microscopy with a hot stage in the temperature range 25 ≤ Tc ≤ 59℃. Our observations show that the crystal patterns are greatly dependent of the crystallization

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Chinese Physics B 2017年第11期26卷 429-433页

作者：张倪侦何孟珂余鹏周大华 Chongqing key laboratory of Photo-Electric functional materials College of Physics and Electronic EngineeringChongqing Normal University Chongqing key laboratory of Multi-scale Manufacturing Technology Chongqing Institute of Green and Intelligent TechnologyChinese Academy of Sciences

Graphene has aroused large interest in optoelectronic applications because of its broad band absorption and ultrahigh electron mobility. However, the low absorption of 2.3% seriously limits its photoresponsivity and restricts the relevant applications. In this paper, a method to enhance the sensitivity of graphene photodetector is demonstrated by introducing electron trapping centers and creating a bandgap structure in graphene. The carrier lifetime obviously increases, and more carriers are collected by the electrodes. Compared with intrinsic graphene detector, the defective graphene photodetector possesses high photocurrent and low-driving-voltage, which gives rise to great potential applications in photodetector area.

关键词： graphene photodetector photocurrent bandgap