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Dislocation Densites of Deformed Steel Sheets Based on Positron Annihilation

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 47-50页

作者： Yonglin Kang Xianjin Wang (Materials science and Engineering School, University of science and technology Beijing, Beijing 100083, China) Materials science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The variation regularity of dislocation densites of some deformed steel sheets under three kinds of strainpaths as uniaxial tension, plane strain and equal biaxial stretching was investigated by means of positron lifetimespectrum and Doppler-broadening techniques. The results show that the increasing rate of dislocation densites isrelated to the plastic strain path. A relationship between the increasing rate of micro-defects, macro-instability andforming limits during the process of steel sheet forming was got based on analyzing the mechanism of dislocationdensity increasing under different stress-strain condihons.

关键词： positron annihilation dislocation steel sheet strain path

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

Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of Materials science & technology 2010年第5期26卷 445-448页

作者： Shuming Wang and Fenghua Kuang School of Materials science and Engineering,University of science & technology Beijing,Beijing 100083,China School of Materials science and Engineering University of Science & Technology Beijing Beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2Al4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2O3 doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3＋ for Al3＋ in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3+ substitution Solid solution

Further study of sources of the imported cobalt-blue pigment used on Jingdezhen porcelain from late 13 to early 15 centuries

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science China(Technological sciences) 2008年第3期51卷 249-259页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & Molecular Engineering, Qingdao University of science & technology, Qingdao 266000, China 2 College of Information science technology, Qingdao University of science & technology, Qingdao 266000, China Institute of Chemistry & Molecular Engineering Qingdao University of Science & Technology College of Information science technology

Based on the conclusion of modern scientific analysis: the cobalt-blue pigment applied on Jingdezhen official porcelain during Yuan Dynasty and prior to Xuande reign of Ming Dynasty (1271―1425) contains high iron and low manganese con- tents, and the cobalt during Xuande and after Xuande periods (after 1426) of Ming Dynasty contains high manganese and low iron contents, in combination with the traditional archaeological method, the related historical textual records were in- vestigated and analyzed, the imported cobalt employed on Jingdezhen official porcelain was studied comprehensively, systematically and logically. In fact, 'Su Ma Li Qing' (Samarra-blue) and 'Su Bo Ni Qing' (Sumatra-blue) are definitely different cobalt ores originated in different places, because of their very similar translitera- tions in Chinese, the confusion has appeared in ancient books for more than 400 years, which considered 'Su Ma Li Qing' and 'Su Bo Ni Qing' as the same co- balt-blue pigment. In this article the mistake was corrected, the possible producing places and the approximate eras of the two pigments imported to China and used at Jingdezhen were also suggested.

关键词： imported cobalt-blue pigments employed on official blue-and-white porcelain Yuan Dynasty early Ming Dy- nasty Mn/Fe content ratio Su Ma Li Qing (Samarra-blue) Su Bo Ni Qing (Sumatra-blue) scientific archae- ological research transliteration

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical Engineering school.University of science and technology Beijing, Beijing 100083, China Metallurgical Engineering School University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

New templates of CNN for extracting corners of objects in gray-scale images

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Journal of University of science and technology Beijing 2003年第3期10卷 73-75页

作者： Lequan Min, Ming Lei, and Xisong DongApplied science School, University of science and technology Beijing, Beijing 100083, China Appl. Sci. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

A new cellular neural network (CNN) with nonlinear templates is presented forextracting convex corners of objects in gray-scale images. Application examples showed that the newCNN can even detect convex corner charact... 详细信息

关键词： cellular neural network extract convex comers gray-scale images

Nonclassical Plane-crystallographic Groups and Their Applications IV

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 228-232页

作者： Lequan Min Xaodan zhang(Applied science School, School,University of science and technology Beijing, Beijing 100083,China) Applied science School University of Science and Technology Beijing Beijing 100083 China

Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are *** can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted bythe projections on the plane of the corresponding unit cells consisting of embedding polyhedrons, respectively. TheFourier-transform patterns of the Periodic lattices have striking approximate'8-fold rotational symmetries', some ofwhich are similar to those displaying in the electrton-diffraction patterns of so-called quasicrystals.

关键词： nonclasslcal crystallographic groups locoally 8-fold symmetry Fourier-transform patterns, quasicrystals

Novel Magnetorheological Suspensions Based on Co-Phthalocyanine/Fe Nanocomposite Particles

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Journal of Materials science & technology 2001年第5期17卷 511-516页

作者： Rongzhou GONG and Zekun FENG Dept. of Electronic science and technology, Huazhong University of science and technology, Wuhan 430074, China Jianguo GUAN and Runzhang YUAN State Key Laboratory of Advanced technology for Materials Synthesis and Processing, Wuhan Univ. of Technol. Wuhan 430070 China

A novel magnetorheological (MR) suspension was based on methyl silicone oil and cobalt-phthalocyanine (Co-Pc)/Fe nanocomposite particles, which were synthesized by thermally decomposing liquid carbonyl Fe in the solution of Co-Pc in N, N-dimethyl formamide. The nanocomposite particles were fully characterized by XRD, SEM and HREM, and the thermal, magnetic and MR properties of nanocomposite particles were measured. Such factors as weight percent of particles (w), magnetic field strength (H), temperature (T) and shear rate (gamma) etc influencing on MR properties were investigated. The results indicated that Co-Pc/Fe nanocomposite with density of 3.66 g/cm(3) was almost micro-sized regular spheroids consisting of tens of Co-Pc coated alpha -Fe nanoparticles in inner and Co-Pc layers on surface of the spheroids. They showed good characteristics of anti-oxidation and soft magnetic. Increment of w increased field-induced shear stress (Delta tau) and zero-field viscosity (eta (0)) of MR suspensions monotonously, and improved anti-settlement stability, but eta (0) increased more markedly than Delta tau with increasing w. Delta tau was basically independent on T and gamma while increased obviously with increasing H. With increasing T, response time of the MR suspension to external magnetic field seemed to decrease. As a result, MR suspensions with satisfactory stability and rapid, completely reversible and significant MR effect can be obtained from Co-Pc/Fe nanocomposite particles.

关键词： Fe Co Novel Magnetorheological Suspensions Based on Co-Phthalocyanine/Fe Nanocomposite Particles

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