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QUANTITATIVE RELATIONSHIP BETWEEN YIELD STRESS AND r-VALUE OF Ti SHEET

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 188-192页

作者： ZHOU Weixian Northwestern Polytechnical university,Xi′an,China Northwestern Polytechnical Univ Xi'an China

Based on the experimental data,it was clarified that the plastic strain ratio R-value is not equal to Hill's r-value for Ti *** the non-quadratic orthotropic yield function pro- posed recently by the author,an optimal expression between yield stress and r-value for Ti sheet was developed on overall *** suitable value of exponent in the function seems to be 6—***,an equation was suggested to estimate strength for the pressure vessel made of Ti sheet.

关键词： Ti sheet yield stress r-value anisotropy

Composition Control of Alloy Coatings and Composition Design of Cathode Targets in Multi-Arc Ion Plating

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Journal of Materials Science & Technology 2000年第3期16卷 348-350页

作者： Jun ZHANG (Shenyang university, Shenyang 110044, China) Shenyang university Shenyang 110044 China

The composition from alloy cathode target to alloy coating generally changes to some extent in multi-arc ion plating. This demixing effect leads to the difficulties in the control of alloy composition of coating and in the design of composition of' alloy cathode target. A new simple formula, an =[(an^***)/∑i(ai^***)].100%, is proposed in present work to deal with the problem. According to this formula, the composition of alloy coating can be calculated by means of the degrees of ionization of alloy elements. The results of calculation agree with the experimental ones within very limited error range. Modifying the formula into another form, an^0=[(an/fn)/∑i(ai/fi)].100%,the design for alloy composition of cathode target can be conveniently carried out, and the ideal composition of alloy coating can be obtained.

关键词： Design Arc

GENERALIZED SIMULATION MODEL FOR MILLED SURFACE TOPOGRAPHY-APPLICATION TO PERIPHERAL MILLING

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Chinese Journal of Mechanical Engineering 2001年第2期14卷 121-126页

作者： Xu Anping Qu Yunxia Li Weimin School of Mechanical Engineering, Hebei university of Technology Zhang Dawei Huang Tian Tianjin university 河北工业大学机械学院天津天津大学天津

Based on analyzing various factors influencing milled surface topography, firstly, a generalized model for milled surface topography is proposed. Secondly, using the principles of transformation matrix and vector operation, the trajectory equation of cutting edge relative to workpiece is derived. Then, a three dimensional topography simulation algorithm is constructed through dividing the workpiece into regular grids. Finally, taking the peripheral milling process as an example, the generalized model is simplified, and the corresponding simulation examples are given. The results indicate that it is very efficient for the generalized model to be used to analyze and simulate the peripherally milled surface topography.

关键词： Generalized simulation model Arbitrary contour mill Peripheral milling process Surface topography

The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province, Yunnan

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 51-63页

作者： Yu Chongwen Jiang Yaosong China university of Geosciences, Beijing China university of Geosciences Beijing

Copper and tin in cassiterite-sulfide deposits of the Gejiu metallogenic province are intimately associatedand show peculiar primary metal zoning. The authors made use of computer techniques to simulatenumerically the zoning of these ore deposits. The study shows that the regular spatial zoning probably resultedfrom the succession of multiple, intermittent and pulsatory mineralizations, The successive transports with di-verse velocities along channelways of the ore-forming solutions, taking place under conditions of definite dif-ference between metal concentrations, in solutions and wallrocks, followed by differential deposition, consti-tute possible dynamic mechanisms for the primary metal zoning.

关键词： Met rate The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province Yunnan

Difference packing arrays and systematic authentication codes

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Science China Mathematics 2004年第4期47卷 566-577页

作者： YIN JianxingDepartment of Mathematics, Suzhou university, Suzhou 215006, China Department of Mathematics Suzhou University Suzhou China

In this paper, a type of combinatorial design (called difference packing array)is proposed and used to give a construction of systematic authentication codes. Taking advantage of this construction, some new series of ... 详细信息

关键词： authentication codes, difference packing arrays, constructions.

RESEARCH OF DYNAMIC CHARACTERIATIC FOR TRANSMISSION SYSTEM

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Chinese Journal of Mechanical Engineering 2001年第1期14卷 74-77页

作者： Qin Shuren School of Mechanical Engineering,Chongqing university 重庆大学机械学院重庆

The kinetic precision of transmission chain is a key problem in the research of gear cutting machine transmission *** traditional point of view is to consider the transmission chain as a geometrical meshing system,thus it is deemed that the kinetic precision of the transmission chain only depends on the manufacturing and assembly errors of its transmission *** further research reveals that the kinetic precision of transmission system is closely related with the system dynamic ***,from the dynamic point of view,it is discerned that not only deems the transmission chain as a geometrical meshing system but also considers it as a dynamic system performing with torsional *** the basis of analyses and processes of measuring data of samples from tests of cutting machine's kinetic precision of transmission chain,the results represent that the influences of dynamic characteristics of the transmission system on its kinetic precision is non *** methods for discerning the transfer function of torsional vibration of gear transmission system and experimental results have been given.

关键词： Dynamic characteristics Gear Transmission system

EXTRACTION KINETICS,SYNERGISTIC EFFECTS AND INTERFACIAL CHEMISTRY FOR D_2 EHPA MPA-Fe^(3+) MIXED EXTRACTION SYSTEM

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Acta Metallurgica Sinica(English Letters) 1993年第12期6卷 405-410页

作者： YU Jingfen LIU Difei Tsinghua university,Beijing,China professor,Dept.of Chemical Engineering,Tsinghua university,Beijing 100084,China Tsinghua Univ Beijing China

The thermodynamics of micella formation,interfacial characteristics,synergistic effects and interfacial kinetics for synergistic extraction system D_2 EHPA-MPA-Fe^(3+) have been *** was found that D_2EHPA in the mixed system strongly exhibits the effect on the micella formation thermodynamics and interracial characteristics of *** ther- modynamic parameters for constants of micelles formation(K_m).free energies of micelles formation(ΔG_m)and critical micella concentrations(CMC)were *** inter- facial adsorption behaviour of D_2EHPA is opposite to that of *** emulsification for single MPA and the mixed system was *** synergistic effects were found in this mixed extraction *** is proved that the process of the Fe^(3+) extraction for non-mixed extraction system is controlled by chemical reaction and the controlling reaction occurs at the interface.

关键词： interfacial chemistry synergistic effect Fe^(3+) extraction kinetics

The Depositional Environment of the Cretaceous Kizilsu Group in Xinjiang——With a Discussion of the Lowermost Marine Horizon of the Cretaceous in the Western Tarim Basin

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 441-453页

作者： Guo Xianpu China university of Geosciences, Beijing Sun Sheping China university of Geosciences Beijing

In this paper. it is demonstrated that there exist marine horizons in the upper part of the lower subcycleand the upper subeycle of the Kizilsu Group in Xinjiang. based on new evidence of authigenic glauconite.boron content. carbon and oxygen stablc isotopic analyses. and lithological and sedimentary features. The up-per part of the lower subeycle is the lowermost marine horizon of the Cretaceous in the western Tarim Basin,which is inferred to be of Barremian age.

关键词： In With a Discussion of the Lowermost Marine Horizon of the Cretaceous in the Western Tarim Basin The Depositional Environment of the Cretaceous Kizilsu Group in Xinjiang

FINITE ELEMENT ANALYSIS OF TRASINENT TWO DIMENSIONAL CHANNEL FLOW WITH A SUDDEN EXPANSION

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Chinese Journal of Mechanical Engineering 1999年第4期12卷 270-275页

作者： Gao Dianrong Zhao Yongkai Wang Yiqun (Yanshan university) Yanshan Univ China

The finite element method is employed to simulate incompressible viscous unsteady flow in two dimensional channel with a sudden expansion. The streamline patterns and the velocity vector plots are presented at different expansion ratios and at different moment. The results obtained have certain significance to analyze the formation of eddies and energy loss in a sudden expansion channel flow and other complex channel flow.

关键词： Sudden expansion channel Finite element method Streamline Velocity Energy loss