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EFFECT OF BIAS STRESS ON NON-LINEAR INTERNAL FRICTION OF Al-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 166-171页

作者： TAN Qi university of Science and technology of China,Hefei,China Univ of Science and technology of China Hefei China

The influence of longitudinal and torsional bias stresses on anomalous amplitude-dependent internal friction was *** longitudinal bias stress may always weaken the anomalous amplitude-dependent effect,while the torsional one may induce different effects from differ- ent directions *** stress effect exhibits only in properly heat treated and cold worked ahoy *** anomalous amplitude-dependent internal friction peaks,P_3,P_2 and P_1, are found to be related closely to slant dislocation kink ***,the application of bias stress to internal friction would be contributed to the study on dislocation structure.

关键词： internal friction bias stress anomalous amplitude effect dislocation kink

CARBIDE FORMATION IN AUSTEMPERED DUCTILE IRON ALLOYED WITH NICKEL AND COPPER

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Acta Metallurgica Sinica(English Letters) 1995年第3期8卷 190-194页

作者： FA N Zhikang (Xi’an university of technology, China)SMALLMANRE(university of Birmingham,UK) Xi'an Univ of Technology Xi'an China

Carbide formation in austempered ductile iron (ADI) alloyed with Ni and Cu has been studied by use of TEM. The results show that η carbide precipitates in the bainitic ferrite when austempered at 350℃.for 6h, but no carbide was found at the austenite/.ferrite interfaces. When austempered at 300℃, two kinds of. s carbides appear in the bainitic ferrite when austempering time reached I h, and X carbide also precipitates at the austenite /ferrite interfaces when austempering time was extended up to 6h. The bainitic. ferrite and the retained austenite follow the Nishiyama- Wasserman relationship,

关键词： carbide austempered ductile iron

A New Clustering Algorithm for Categorical Attributes

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 318-322页

作者： Songfeng Lu, Zhengding Lu (College of Computer Science and technology, Huazhong university of Science and technology, Wuhan 430074, China) College of Computer Science and technology Huazhong University of Science and Technology Wuhan 430074 China

In traditional data clustering, similarity of a cluster of objects is measured by distance between objects. Such measures are not appropriate for categorical data. A new clustering criterion to determine the similarity between points with categorical attributes is pre- sented. Furthermore, a new clustering algorithm for categorical attributes is addressed. A single scan of the dataset yields a good clus- tering, and more additional passes can be used to improve the quality further.

关键词： data mining clustering similarity Information

EXPERIMENTAL STUDY ON TRIBOLOGICAL PROPERTIES OF FULLERENE COPOLYMER NANOBALL

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Chinese Journal of Mechanical Engineering 2000年第3期13卷 201-205页

作者： Lei Hong (School of Mechanical Science and Engineering, Huazhong university of Science and technology) Guan Wenchao, Liao Daoxun (Huazhong university of Science and technology) 华中科技大学湖北武汉

A novel fullerene-styrene-maleic anhydride copolymer is reported. TEM analyses shows it is water- soluble nanoball of average diameter of about 83 nm. The tribological behavior is evaluated by foul-ball machine. It was found that addition of fullerene copolymer to base stock (2%triethanolamine aqueous solution)resulted in a raise in load-carrying ability(F value)from 130 N to maximum 480 N, and a reduction in coefficient of friction from 0.235 to minimum 0. 063. SEM analyses indicates that the wear scare obtained with fullerene copolymer exhibited mild scratches, while sharp grooving and serious pull-out phenomnon were observed in the presence of base stock without additive .The improvements in friction, wear and load-carrying capacity are probably due to the presence of fullerene copolymer nanoballs, which may act as molecule ball bearings, which in turn lead to elastic rolling lubrication.

关键词： Water-soluble Fullerene copolymer Nanoball Fricition and wear Microcosmic elastic rolling8

ARTIFICIAL NEURAL NETWORK AND FUZZY LOGIC CONTROLLER FOR GTAW MODELING AND CONTROL

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 53-56页

作者： Gao Xiangdong Faculty of Mechanical and Electrical Engineering，Guangdong university of technology， Guangzhou 510090，China Huang Shisheng South China university of technology Faculty of Mechanical and ELectrical Engineering Guangdong University of Technology Guangzhou 510090 South China university of technology

An artificial neural network(ANN) and a self-adjusting fuzzy logiccontroller(FLC) for modeling and control of gas tungsten arc welding(GTAW) process are *** discussion is mainly focused on the modeling and control of the weld pool depth with ANN and theintelligent control for weld seam tracking with FLC. The proposed neural network can produce highlycomplex nonlinear multi-variable model of the GTAW process that offers the accurate prediction ofwelding penetration depth. A self-adjusting fuzzy controller used for seam tracking adjusts thecontrol parameters on-line automatically according to the tracking errors so that the torch positioncan be controlled accurately.

关键词： Artificial neural network Fuzzy logic control Weld pool depth Seamtracking

Evolution of Bright Screening-photovoltaic Spatial Optical Solitons

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Chinese Journal of Lasers 2001年第5期10卷 28-33页

作者： LIU Jinsong (State Key Laboratory of Laser technology, Huazhong university of Science and technology, Wuhan 430074, China) 华中科技大学激光技术国家重点实验室湖北武汉

A numerical analysis of the dynamical evolution of bright screening photovoltaic (SP) spatial solitons in biased photovoltaic photorefractive materials in the case of neglecting the material loss and the diffusion is presented. When an incident optical beam is a bright SP soliton, the beam propagates along a linear path with its shape kept unchanged. When the incident optical beam is slightly different from a bright SP soliton, the beam reshapes itself and tries to evolve into a bright SP soliton after a short distance. However, when the incident optical beam is significantly different from a SP bright soliton, the beam cannot evolve into a stable bright SP soliton, and tends to experience periodic compression and expansion. For a low intensity input beam, the wave experiences a periodic process of compression first and then expansion during the initial part of the cycle. For a high intensity input beam, however, the wave will initially diffract and then experiences compression during the cycle.

关键词： nonlinear optics spatial optical solitons photorefractive effects

IMPROVEMENT IN TENSILE PROPERTIES OF α+β TYPE Ti ALLOYS BY HYDROGEN TREATMENT

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Acta Metallurgica Sinica(English Letters) 1993年第2期6卷 121-124页

作者： GONG Bo LAI Zuhan Northeast university of technology,Shenyang,ChinaNIINOMI Mitsuo,KOBA YASHI Toshiro Toyohashi university of technology,Toyohashi Japan Department of Physics,Northeast university of technology,Shenyang 110006,China Northeast Univ of technology Shenyang China

A new process to refine the microstructure of α+βtvpe Ti alloys was developed by using hydrogen as a temporary alloying *** involves hydrogenating the alloys below the hydrogenated β transus temperature about 0-40 K,air cooling to room temperature and then dehydrogenating at 948 ***-6AI-4V and Ti-5AI-2.5Fe alloys treated hy this new process show much refined microstructures,and the yield strength,ultimate strength as well as the elongation increase 8—15,5—13 and 7—14% respectively

关键词： Ti-6Al-4V Ti-5Al-2.5Fe thermochemical processing(TCP) microstructural refinement tensile properties

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

STUDY ON PHOTOCATALYTIC MECHANISM OF SOL-GEL-DERIVED Pb-DOPED TiO_2 THIN FILMS

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Journal of Wuhan university of technology(Materials Science) 1999年第4期14卷 1-8页

作者： YU Jiaguo ZHAO Qingnan ZHAO Xiujian Wuhan university of technology Wuhan university of technology China State Key Lab Adv. Technol. Mat. S. Wuhan University of Technology Wuhan 430070 China

Pb-doped TiO2 photocatalytic thin films were prepared on a soda-lime glass substrate via sol-gel method using TiO2 sol solution containing lead and characterized by X-ray photoelectron spectroscopy (XPS). The results showed that besides oxides of Ti(IV) there is a certain amount of oxides of To(?) and Ti(?) and Pb exists in the forms of PbTiO3 and PbO. The photocatalytic activity of the Pb-doped TiO2 films was evaluated by the photocatalytic decolorization of aqueous methyl orange and photocatalytic mechanism mas also analyzed.

关键词： sol-gel method Pb-doped TiO2 thin films XPS photocatalytK mechanism