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Simultaneous Thermoluminescence and Thermally Stimulated Current in Polyamide

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Journal of Materials Science & Technology 1998年第4期14卷 357-360页

作者： Fan, Yong Wang, Xuan Zhang, Xiaohong Lin, Jiaqi Lei, Qingquan harbin univ Sci & Technol Dept Elect Mat Engn Harbin 150040 Peoples R China

The simultaneous thermoluminescence (TL) and thermally stimulated current (TSC) spectra were obtained in two types of polyamide film, such as nylons 6 and 11 under study of electron detrapping and recombination. There are three main relaxation peaks or regions, designated gamma , beta and alpha in order of increasing temperature in the TSC spectra, in contrast, a high temperature relaxation peak in TL spectra disappears. The centers of peaks of these relaxation regions are located at near 180, 230 and 310 K, respectively, deviating plus or minus 10 K. However, two anomalous phenomena were observed: firstly, a very large, short-circuited, thermally stimulated discharge current (TSDC) is up to 10** minus **8A, but reversible in direction for non-polarized nylons 6 and 11, even after several times repeatedly; secondly, there is no TL signal except for non-polarized nylon 6 film. (Edited author abstract) 11 Refs.

关键词： Polyamides

SYNTHESIS OF ALLANTOIN USING HETEROPOLY COMPOUNDS AS CATALYSTS

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Chinese Chemical Letters 1995年第4期6卷 337-338页

作者： Sui Mei ZHANG Feng Lian ZHAO Wei Qing WANG(Department of Chemical Engineering, harbin Engineering university,harbin, 150001) harbin engn univ Dept Chem Engn Harbin 150001 Peoples R China

Allantoin was synthesized with the yield as high as 68.5% using H3PW12O40. xH(2)O as catalyst. Optimum conditions for the synthesis were determined. It. was found that the heteropoly compound has higher catalytic acti... 详细信息

关键词： AS SYNTHESIS OF ALLANTOIN USING HETEROPOLY COMPOUNDS AS CATALYSTS

Performance tests of multi-metal zincate solutions with zinc sulfate and zinc oxide

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Rare Metals 2007年第S1期26卷 99-104页

作者： HUANG Xiaomei,and ZHANG Milin College of Materials Science and Chemical Engineering,harbin Engineering university,harbin 150001,China harbin engn univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron *** was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc ***,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was ***,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the *** results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating *** zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.

关键词： Al-Si alloy multi-metal zincating solution adhesion

AN ANALYSIS FOR DIFFRACTION OF FLEXURAL WAVES AND DYNAMIC STRESS CONCENTRATIONS IN THICK PLATES WITH A CAVITY

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Acta Mechanica Solida Sinica 1997年第2期10卷 167-178页

作者： Hu, C Ma, XR Huang, WH Liu, DK harbin INST TECHNOL HARBIN 150001PEOPLES R CHINA harbin engn univ HARBIN 150001PEOPLES R CHINA

By using the complex variable method and conformal mapping, the diffraction of flexural waves and dynamic stress concentrations in thick plates with a cavity have been studied. A general solution of the stress problem of the thick plate satisfying the boundary conditions on the contour of an arbitrary cavity is obtained. By employing the orthogonal function expansion technique, the dynamic stress problem can be reduced to the solution of an infinite algebraic equation series. As an example, the numerical results for the dynamic stress concentration factor in thick plates with a circular, elliptic cavity are graphically presented. The numerical results are discussed.

关键词： thick plate diffraction of flexural waves dynamic stress concentration complex variable method conformal mapping

Properties of Aluminum Oxide (AlO_x) Barrier Coatings Deposited on Poly(Ethylene Terephthalate)(PET)Substrates by Reactive Magnetron Sputtering

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稀有金属材料与工程 2012年第S1期41卷 268-271页

作者： Liu Zhuang Ma Xinxin Sun Zhihui Xu Fangjun harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China harbin univ Commerce Harbin 150028 Peoples R China

The aluminum oxide(AlOx)coatings were deposited on poly(ethylene terephthalate)(PET)surface by reactive magnetron sputtering for improving its barrier *** O2 flux increasing,three modes including metallic mode,transition mode and oxide mode exist in *** properties of the aluminum oxide(AlOx)coatings prepared at different modes were ***,the influences of oxygen flux on the stoichiometry,structure,gas permeation of the coatings were *** chemical composition of AlOx films fabricated in transition mode is different as oxygen flux varies slightly,and the gas barrier property is better as the stoichiometry is closer to 1.5 with oxygen flux *** coating uniformity,roughness and particle size depend remarkably upon oxygen *** coatings deposited at oxide mode have a good barrier performance to oxygen and water,and the permeability to oxygen decreases by sixty times and water vapor ten times compared with uncoated

关键词： permeation barrier aluminum oxide magnetron sputtering poly(ethylene terephthalate)(PET)

Effect of non-cyanide zincation process parameters on the microstructure of the zincation layer on A356 alloys

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Rare Metals 2007年第S1期26卷 313-317页

作者： ZHU Zhaojun1),and HUANG Xiaomei2)1) School of Materials Science and Engineering,harbin Institute of Techmology,harbin 150001,China 2) College of Materials Science and Chemical Engineering,harbin Engineering university,harbin 150001,China harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China harbin engn univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

The effects of non-cyanide zincation process parameters on the microstructure of the zincation layer on A356 alloy were investigated by scanning electronic *** the increasing of zincation time,the zinc grain size and the number density increase gradually,and the zinc grains adhere each *** zinc grain obtained in the double-dipping process is finer,compacter and more homogeneous than that obtained in the single-dipping *** the increasing of the zincation temperature,the morphology of zinc grains changes from spherical shape to flake-like ***,higher zincation temperature results in the flaking off of the zincation layer from the *** optimized zincation temperature is 20-30 ℃.The quality of the zincation layer obtained in a low concentration,non-cyanide and multi-element zincation solutions is much better than these obtained in conventional high concentration zincation solution,dilute zincation solutions or a dilute zincation solution containing *** addition,the matrix alloy and the pre-treatment also have significant influence on the morphology of the zincation layer.

关键词： non-cyanide zincation solution zincation time zincation temperature morphology

Characterization of microstructural length scales in directionally solidified Sn-36%Ni peritectic alloy

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Transactions of Nonferrous Metals Society of China 2013年第8期23卷 2446-2453页

作者： Peng PENG Xin-zhong LI Yan-qing SU Dong-mei LIU Jing-jie GUO Heng-zhi FU harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

Sn–36%Ni peritectic alloys were directionally solidified at different growth rates under a constant temperature gradient (20 K/mm), the dependences of microstructural characteristic length scales on the growth rate were investigated. Experimental results are presented, including primary and higher order dendrite arm spacings λ 1 , λ 2 , λ 3 and dendrite tip radius R of primary Ni 3 Sn 2 phase. Comparisons between the theoretical predictions and the experimental results show that, for the primary dendrites, λ 1 =335.882 v −0.21 , which is in agreement with the Kurz–Fisher model; for the secondary dendrites, λ 2 =44.957 v −0.277 , which is consistent with the Bouchard–Kirkaldy model; for the tertiary dendrites, λ 3 =40.512 v −0.274 ; for the dendrite tip radius, R =22.7 v −0.36 . The experimental results also show that the λ 1 / λ 2 changes greatly with increasing growth rate while the λ 1 / λ 3 has no significant change, indicating that tertiary dendrite arms have a more similar growth characteristics to primary dendrites compared with secondary dendrites. The λ 1 / R ranges from 2 to 2.3 with the increase of growth rate.

关键词：定向凝固组织包晶合金微观结构枝晶臂间距表征镍枝晶尖端 er模型

A FINITE-ELEMENT ANALYSIS OF ELECTROMAGNETIC SHEET METAL-EXPANSION PROCESS

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中国有色金属学会会刊：英文版 1998年第3期8卷 135-140页

作者： Huang, SY Chang, ZH Wang, ZR Wang, LF Yang, M Wuhan Automot Polytech univ Sch Mat Engn Wuhan 430070 Peoples R China harbin Inst Technol Sch Mat Sci & Engn Harbin 150006 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＥｌｅｃｔｒｏｍａｇｎｅｔｉｃｆｏｒｍｉｎｇ，ｅｓｅｎｔｉａｌｙｂｅｉｎｇａｋｉｎｄｏｆａｐｐｌｉｃａｔｉｏｎｏｆｉｍｐｕｌｓｅｉｎｔｅｎｓｉｖｅｃｕｒｅｎｔｔｅｃｈｎｉｑｕｅｉｎｍｅｔａｌ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＥｌｅｃｔｒｏｍａｇｎｅｔｉｃｆｏｒｍｉｎｇ，ｅｓｅｎｔｉａｌｙｂｅｉｎｇａｋｉｎｄｏｆａｐｐｌｉｃａｔｉｏｎｏｆｉｍｐｕｌｓｅｉｎｔｅｎｓｉｖｅｃｕｒｅｎｔｔｅｃｈｎｉｑｕｅｉｎｍｅｔａｌｗｏｒｋｉｎｇ，ｄｅａｌｓｗｉｔｈ...

关键词： finite element analysis electromagnetic forming magnetic pressure

Micro-arc oxidation coatings on Mg-Li alloys

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Rare Metals 2009年第2期28卷 160-163页

作者： Xu Yongjun Li Kang Yao Zhongping Jiang Zhaohua Zhang Milin harbin Inst Technol Dept Appl Chem Harbin 150001 Peoples R China harbin engn univ Key Lab Minist Educ Super Light Mat & Surface Technol Harbin 150001 Peoples R China

Micro-arc oxidation (MAO) method was used for the surface modification of an Mg-5wt.%Li alloy. Ceramic coatings were in-situ fabricated on the Mg-Li alloy. The morphology feature,phase composition,and corrosion-resistance of the formed ceramic coatings were studied by SEM,XRD,and electrochemical methods,respectively. The results showed that the coatings produced in a sodium silicate solution system were composed of MgO and Mg2SiO4. The ceramic coating became thicker and the content of Mg2SiO4 phase increase...

关键词： Mg-Li alloys ceramic coatings micro-arc oxidation corrosion resistance