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Calculation Models of Mass Action Concentrations for Metallic Melts Involving Monotectic

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Journal of university of science and technology beijing 2001年第4期8卷 248-253页

作者： Jian Zhang Metallurgy School, university of science and technology beijing, beijing 100083, China Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams, measured activities as well asDeltaG(m) and DeltaG(xs), calculating models of mass action concentrations for metallic melts involving monotectic have been formulated. The calculated results agree with practice on the whole, showing that the models deduced generally can reflect the structural characteristics of these melts. The metastable compounds formed in the melts are of the types A(2)B(3), AB(2), A(2)B(3) or AB and A(2)B(3)+AB etc..

关键词： metallic melts monotectic activity mass action concentration

Phenomenological Modeling of Warm Compaction and Experimental Verification

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 292-295页

作者： Shiju Guo, Tao Lin (Material science and Engineering School, university of science and technology beijing, beijing 100083, China) Material science and Engineering School University of Science and Technology Beijing Beijing 100083 China

A phenomenological modeling approach to establishing the warm compaction equation and curves by modifying the regression equation of the room-temperature compaction curve is presented. An enhanced factor of compacting pressure is introduced into the equation in order to reveal the effects of powder/die temperature and filling height of powders on green density. Compaction curves yielded from this equation are consistent with the experimental data of ATOMET grade iron powders. The curves show that the powder/ die temperature should reduce as the filling heights of powders increase and that in some cases warm compaction can not give rise to a higher green density.

关键词： powder metallurgy warm compaction compaction equation Materials

Electrochemical Study on the Change in Valency of Niobium Oxide in the MnO-SiO_2-Nb_2O_5 System

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Rare Metals 1990年第1期10卷 1-4页

作者： Tan Zanlin Wei Shoukun university of science and technology beijing 北京科技大学北京

Change in valency of Nb-oxide in MnO-SiO_2-Nb_2O_5 system was studied with the electrochemical method using ZrO_2 as the solid *** analysis has shown that the only possible reaction that could take place at the working elec- trode is:2(Nb_2O_5)=2(Nb_2O_4)+O_2 with the a_0 values experimentally evaluated,values of a Nb_2O:/a Nb_2O:were calculated and isoactivity-ratio curves drawn in MnO-SiO_2-Nb_2O_5 triangles at 1418 and *** simultaneous existence of tetra-and penta-valent Nb mineral constituents in industrial Nb-bearing slags was thus verified experimentally.

关键词： Electrochemical Study on the Change in Valency of Niobium Oxide in the MnO-SiO2-Nb2O5 System SiO MnO

Annealing Texture Evolution of Ti-IF Steel during Batch Annealing

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 175-179页

作者： Jing Shi Xianjin Wang(Material science and Engineering School, university of science and technology beijing, beijing 100083, China) Material science and Engineering School University of Science and Technology Beijing Beijing 100083 China

Texture development and recrystallization behavior of Ti-IF steel during Batch Annealing (BA) were investigared with X-ray diffraction and EBSP in lab, and the results were compared with research work on continu ous annealing (CA) with rapid heating rate. The basic tendencies are similar that eary nucleation takes place in ND fibers, RD fibers are consumed at the end of recrystallization, and ND texture dominates over annealing texture. However, the detailed texture transformation during batch annealing is different and somewhat more compicated than tha in rapid-heating process. Moreover, misorientation plays an important role in texture transformation of BA In addition, the results of EBSP are consistent with that of ODF well.

关键词： Ti-IF steel texture batch annealing X-ray diffraction EBSP

Entropy number and non-linear approximations on multivariate Besov space by manifolds of finite pseudo-dimension

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Progress in Natural science:Materials International 2006年第3期16卷 260-265页

作者： LONG Jingfan and FANG Gensun (School of Mathematical sciences, beijing Normal university, beijing 100875, China Department of Computer science, information technology Institute, beijing 100101, China) School of Mathematical sciences Beijing Normal University Beijing 100875 China Department of Computer science Information Technology Institute Beijing 100101 China

We determine the asymptotic order of entropy number and optimal non -linear approximations of anisotropic periodic Besov class of Bpθr(Td') (1≤p≤∞,1≤0≤∞) by manifolds of finite pseudo-dimension in the metric Lq... 详细信息

关键词： Pseudo-dimension anisotropic Besov class of functions entropy number nonlinear width.

PREDICTION AND CONTROL OF BOTH WRINKLE AND FRACTURE LIMITS ON CYLINDRICAL CUP MULTI DEEP DRAWING

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Chinese Journal of Mechanical Engineering 1999年第4期12卷 288-296页

作者： Lei Junxiang Yantai universityKang Yonglin university of science and technology beijing 烟台大学机械工程系山东烟台 264005 北京科技大学压力加工系北京

Based on the superfluous triangle material wrinkle model,the no wrinkle limit criterion of cylindrical cup multi deep drawing is calculated as the prediction and control of the wrinkle *** to fracture model,the no fracture limit criterion of cylindrical cup multi deep drawing is calculated as the prediction and control of the fracture *** the no wrinkle limit criterion with the no fracture limit criterion,the no wrinkle and no fracture limit criterion and diagram on cylindrecal cup multi deep drawing are given as the prediction and control of both wrinkle and fracture *** accordance with this can determine the limit deep drawing coefficient and minimum deep drawing coefficient,and can choose the deep drawing coefficient of multi deep drawing,blank holder force and deformation force by optimization choice *** calculation and test data are highly consistent,and suitable for no flange multi deep drawing,flange multi deep drawing and rigid punch expanding

关键词： Cylindrical cup Multi deep drawing Wrinkle limit Fracture limit control Optimization choice method

Application of Potentiostats Using PC in the Phase Analysis of Galvano-Chemis-try

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 151-153页

作者： Bo Wen Xinyu Liu Xinhua Wang Wanjun Wang Xang Ma(information Engineering School, university of science and technology beijing, beijing 100083, China)(Metallurgy School, university of science and technology beijing, beijing 100083, China)(beijing Resea information Engineering School University of Science and Technology Beijing Beijing 100083 China Metallurgy School University of Science and Technology Beijing Beijing 100083 China beijing Research Institute of Iron and Steel Beijing 100081 China

A set of device is designed based on PC to realize the functions of traditional potentiostats in the phase ana1ysis of galvanochemistry. In the device, A/D and D/A conversion is used to measure the electrode potential and convert the voltage for outPut; specific program runs in the PC to regulate and control the system. The effect of the proportion factor Kp on the control variation is researched through certain experiment. Two experiments, the control of electrolysis in constant poteniial and the determination of polarization curves, are designed to test and evaluate the effectiveness of the device. The experimemel results show that the variation between the actualanode potential and the target potential could be controlled to below 1 mV if Kp is set to an appropriate value.

关键词： potentiostat PC phase analysis of galvano-chemistry

Special Orientation Relationships Observed at the Early Stages of Recrystallization in Pure AlMn Alloy

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 140-146页

作者： Ping Yang(Material science and Engineering School, university of science and technology beijing, beijing 100083, China)(Institute for Metal science and Metal Physics, Aachen university of technology, D-52056, Aachen, Germany) Material science and Engineering School University of Science and Technology Beijing Beijing 100083 China Institute for Metal science and Metal Physics Aachen University of Technology D-52056 Aachen Germany

Electron Back Scattering Diffraction (EBSD) technique in a SEM was used to obtain local orientationalinformation on new grains and their surrounding deformed matrices at the early stages of recrystallization in pureA1-1 .3%Mn alloy. Results show that special orientation relationships including twin-relationship often exist betweennew grains, between new grains and deformed grains or between deformed grains. The occurrence of such specialorientation relationships is attributed to the special deformation behavior in the samples with large initial grain *** formation of recrystallization twins is discussed in a different way to those of traditional ones.

关键词： Orientation relationship recrystallization AlMn, EBSD

Identification of Nonlinear Dynamic Systems Using Diagonal Recurrent Neural Networks

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 149-151页

作者： Jing Wang Hui Chen(information Engmeering School, university of science and Techaology beijing, beijing 100083, China) information Engineering School University of Science and Technology Beijing Beijing 100083 China

In order to apply a new dynamic neural network- Diagonal Recurrent Neural NetWork (DRNN) to the system identificationof nonlinear dynamic Systems and construct more accurate system models, the structure and learning method (DBP algorithm) of theDRNN are Present6d. Nonlinear system characteriStics can be identified by presenting a set of input / output patterns tO the DRNN andadjusting its weights with the DBP algorithm. Experimental results show that the DRNN has good performances in the identification ofnonlinear dynamic systems in comparison with BP networks.

关键词： neural network system identification intelligent control control system models learning method