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Journal of Materials Science & Technology 2003年第5期19卷 419-421页

作者： Shiming HAO, Yuping REN, Hua DING, Dapeng WANG, Gang ZHAO and Hongxiao LISchool of Materials and Metallurgy, Northeastern university, Shenyang 110004, China Sch. of Mat. and Metall. Northeastern Univ. Shenyang 110004 China

Through microstructure observation and X-ray diffraction analysis, the equilibrium phase constituents of Al-Zn alloy that contains 2 at. pct Cu at room temperature have been determined as Al-based solid solution (α), Zn-based solid solution and AI4Cu3Zn phase (T'-phase), which are different from a phase, Zn phase and CuZn4 phase originally believed. It is determined that the products of discontinuous precipitation transformation below 277℃ are not the equilibrium phase constituents, but the metastable phases made up of a phase, Zn phase and CuZn4 phase. The phase constituents after discontinuous precipitation of AIZn-2Cu alloy would transform to the ones in equilibrium status: Al-based solid solution (α) in fcc structure, Zn-based solid solution in hcp structure and AI4Cu3Zn phase (T'-phase) ultimately through plastic deformation at room temperature and re-heating treatment below 277℃.

关键词： Al-Zn-Cu alloy Discontinuous precipitation Phase constituents Deformation

MOTIONS OF ALLOYING ADDITIONS IN GAS STIRRED LADLES

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Acta Metallurgica Sinica(English Letters) 2001年第5期14卷 359-367页

作者： S.C. Fan, B.K. Li and J.C. He Department of Thermal Engineering, Northeastern university, Shenyang 110004, China Dept. of Thermal Eng. Northeastern Univ. Shenyang 110004 China

A mathematical model has been developed to analyze the flow patterns and subsurface trajectories of spherical shaped particles (alloy additions) in gas stirring ladles. First, a numerical method to solve fluid flow problems in conjunction with a curvilinear coordinate system is proposed. The internal boundary in flow field, which must be designated in the cylindrical polar coordinate system, can be avoided by using body- fitted coordinate system (BFC). Consequently, computed flow of molten steel and paths of alloying additions are able to cross smoothly the geometric centerline of cylindrical vessel. Second, motion of particles is calculated in the three-dimensional coordinate system, the modification of parameters, such as the drag coefficient and density in the gas plume region, is examined. When the density of sphere is closer and closer to that of fluid, the path of motion is longer and longer. If the plug is moved off-centered to the half of radius, the path of sphere is prolonged, and the sphere may go through the geometric centerline of vessel, reach the deeper region. The immersed depths increase with increasing entry velocities.

关键词： alloying addition gas stirring ladle motion

Phase formation regularities in Fe-based nanometer powders prepared by gas evaporation process

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中国有色金属学会会刊：英文版 2001年第5期11卷 725-728页

作者：陈振华严红革陈刚康智涛黄培云 Cent S univ Dept Mat Sci & Engn Changsha 410083 Peoples R China

A serials of Fe based nanometer powders were fabricated by reduced pressure gas evaporation process with induction current as the heating source. The formation regularities of the phases in as prepared powders and the structures of the nanometer particles were investigated. Pure Fe nanometer powders with about 70% γ Fe phase is prepared in present study by using the powder collector with good cooling effect. In the nanometer powders of Fe Ni alloy, solid solution phase γ (Fe,Ni) and α Fe phase form, but for Fe Cr alloys only solid solution phase α (Fe,Cr) forms. In the nanometer powders of Fe Cu alloy, only pure metal phases of γ Fe and Cu form, and no compound or solid solution phase exists. The formation regularity of the phases in the nanometer powders of alloys obeys the common phase laws in bulk alloy state.

关键词： gas evaporation nanometer powder Fe based powder

Surface acoustic wave sensor system applied to the kinetic study of urease in plant seeds

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Chinese Journal of Chemistry 1995年第3期13卷 231-240页

作者： LIU, DZ CHEN, K GE, K NIE, LH YAO, SZ HUNAN univ NEW MAT RES INSTCHANGSHA 410082PEOPLES R CHINA

A new type of the surface acoustic wave (SAW) sensor system was delivered. Urease from several kinds of plant seeds was extracted with different extracting solvents. The urease activity, Michaelis constant and other kinetic parameters were estimated for the first time by means of the new device-SAW sensor system. Some factors such as pH, temperature, activators and inhibitors are also discussed. The method can be applied to the determination of urea content in human urine and the experimental results consist with those reported.

关键词： SURFACE ACOUSTIC WAVE SENSOR UREASE UREA KINETIC PARAMETERS

Characteristics　on　Cerium　Promoted　Iron　Based　Catalyst　forDehydrogenation　Ethylbenzene　to　Styrene

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Journal of Rare Earths 1996年第2期14卷 81-87页

作者：祝以湘胡云行 XIAMEN univ COLL CHEM & CHEM ENGNXIAMEN 361005PEOPLES R CHINA

it was found by XPS and XRD that cerium existed as CeO_2 in iron based catalyst for dehydrogenation of ethylbenzene to styrene. and CeO_2 can be partly reduced under the reaction conditions to create Ce(3+)/Ce(4+) redox couples in the catalyst. The experiment of XPS and TPR-GC showed that there is an interaction between Ce oxide and Fe oxide, resulting in the shift of negative charge from iron to cerium and in the difficulty of Fe_2O_3 reduction to Fe_3O_4 in Fe_2O_3-CeO_2 *** role of cerium promoter in the catalytic process was supposed to enhance the electron transfer among neighboring Fe active-sites of the catalyst and to improve the redox process of ethylbenzene dehydrogenation in the presence of steam by transferring oxygen from water to the active phase of the catalyst.

关键词： Dehydrogenation XPS TPR Cerium promoter Cerium oxide

ADSORPTION AND ACTIVATION OF METAL IONS ON KYANITE

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中国有色金属学会会刊：英文版 1996年第3期6卷 22-24页

作者： Dong Hongjun Chen Jin(Department of Mineral Engineering,Central South university of Technology, Changsha 410083) CENT S univ TECHNOL DEPT MINERAL ENGNCHANGSHA 410083PEOPLES R CHINA

ＡＤＳＯＲＰＴＩＯＮＡＮＤＡＣＴＩＶＡＴＩＯＮＯＦＭＥＴＡＬＩＯＮＳＯＮＫＹＡＮＩＴＥ￥ＤｏｎｇＨｏｎｇｊｕｎ；ＣｈｅｎＪｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭｉｎｅｒａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵ... 详细信息

ＡＤＳＯＲＰＴＩＯＮＡＮＤＡＣＴＩＶＡＴＩＯＮＯＦＭＥＴＡＬＩＯＮＳＯＮＫＹＡＮＩＴＥ￥ＤｏｎｇＨｏｎｇｊｕｎ；ＣｈｅｎＪｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭｉｎｅｒａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏ...

关键词： metal ion kyanite sodium oleate adsorption flotation

Synthesis　and　Structure　Determination　of　Yttrium　Alkoxides　and　Alkoxy　Yttrium　Monomers　with　Double　Bond

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Journal of Rare Earths 1996年第1期14卷 1-7页

作者：生瑜陈利永章文贡 FUJIAN NORMAL univ INST POLYMER SCIFUZHOU 350007PEOPLES R CHINA

Ten alkoxy yttrium monomers with double bond,Y(OR) 3-n(OCOCH=CHCOOR).(n=1 or 2,R=alkyl),are *** molecular structures are determined by analysis of yttrium content,infrared spectra and nuclear magnetic resonance spectra

关键词： Yttrium Monomer Maleic anhydride

Measurement of Infinite Diluted Activity Coefficient of Solvents in Polymer by Inverse Gas Chromatography Method

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Chinese Journal of Chemical Engineering 2000年第2期8卷 167-170页

作者：冯媛媛叶汝强刘洪来 E China univ Sci & Technol Dept Chem Shanghai 200237 Peoples R China

The infinite diluted activity coefficients of solvents in polyisopropyl methylacrylate was measured using inverse gas chromatography. The solvents used were benzene, toluene, ethyl benzene, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methanol, ethanol isopropyl alcohol, butyl alcohol, 1,2-dichloroethane, and chloroform. It was observed that the infinite diluted activity coefficient of alcohols are well above those of the other solvents investigated.

关键词： infinite diluted activity coefficient inverse gas chromatography specific retention volume poly(isopropyl methacrylate) thermodynamics

1,3-Dipolar Cycloaddition Reaction between Vinyl Acetate and N-Alkyl Hydroxypyridinium Halide

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Chinese Chemical Letters 2001年第12期12卷 1053-1054页

作者： Zhou, SF Su, JY Zeng, LM Zhongshan univ Sch Chem & Engn Guangzhou 510275 Peoples R China

1, 3 Dipolar cycloaddition reaction between vinyl acetate and 3-hydroxypyridiniun betaine was performed under solid-liquid phase transfer catalytic condition, This reaction has been successfully used on the synthesis ... 详细信息

关键词： 1,3-dipolar cycloaddition 3-hydroxypyridiniun betaines dipolarphiles

A NEW HIGH ORDER SCHEME FOR CONVECTION EQUATION AND ITS APPLICATION

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Journal of Hydrodynamics 2002年第1期14卷 81-86页

作者： Zhang Xiao-feng (Department of River Engineering, Wuhan university, Wuhan 430072, China) Zhang Hong-wu (Department of Hydraulic Engineering, Tsinghua university, Beijing 100084, China) Tamotsu Takahashi, Hajime Nakagawa (Disaster Prevention Research Dept. of River Eng. Wuhan Univ. Wuhan 430072 China

With the undetermined coefficient method, a new high order scheme for convection equation named as HAUC was worke d out. The accuracy of the new scheme was analyzed by comparing the computed res ults with the exact solutions of 1-D pure convection equation and nonlinear con vection equation. The effectiveness of the HAUC was also examined by comparing w ith the results obtained by other schemes. Finally, it was applied to simulate 1 -D dam break flow with differenct ratios of initial upstream water depth to do wnstream one. The results show that the scheme has the ability to simulate both undular bores and moving hydraulic jumps.

关键词： higher order scheme undetermined co efficient method dam break flow undular bore moving hydraulic jump