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Journal of Magnesium and Alloys 2022年第5期10卷 1256-1267页

作者： y.J.Wan y.zeng y.C.Dou D.C.Hu X.y.Qian Q.zeng K.X.Sun G.F.Quan Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Material Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China College of Materials Science and Engineering Sichuan University of Science and EngineeringZigong 643000China Department of Materials The University of ManchesterOxford RoadManchester M139PLUnited Kingdom

Aging prior to twinning deformation was proposed to alter the precipitate orientation of the plate-shapedβ-MgAlfrom(0002)basal planes(named basal plates)to■prismatic planes(named prismatic plates)in AZ31 Mg *** experimental results showed that the compressive yield strength(CyS)of the sample containing prismatic plates increased 40 MPa and the compression ratio raised by 22%compared to that containing basal *** underlying strengthening mechanism was analyzed via a yield strengthen(yS)model with a function of grain size,precipitate characters(size,oritention,fraction)and Schmid factor(SF).It revealed that the improvement of CyS was mainly attributed to the altered precipitate orientation and refined grain size produced by twinning ***,the prismatic plates always have a stronger hardening effect on basal slip than basal plates under the same varites of precipitate diameter and ***,the decreased CRSS ratio of prismatic slip to basal slip revealed that the activity of non-basal slip in Mg alloy might be *** activated slip systems provided more mobile dislocations,contributing to the large compression ratio of the Mg rolled sheet with prismatic plates.

关键词： Precipitate orientation Precipitation strengthening Grain boundary strengthening yield strength model

SNOEK-Kê-K■STER PEAK OF INTERNAL FRICTION IN Fe-P-N ALLOyS

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 12-18页

作者： y.y.Che G.y.zeng y.C.Xu J.W Ji Northeastern Univ Shenyang China

The internal friction and precipitate phases of the deformed Fe-P-N alloys have been investigated. It has been found that the ratio of depends on the content of P and the relation holds if the content of N is lower than *** and the content of P is lower than ***. It shows that the intercept K2 is related to the presence of the atomic pairs and clusters of P in the alloy matrix.

关键词： internal friction Fe-P-N alloy

DSC AND TEM STUDy OF ULTRA HIGH STRENGTH ALUMINUM ALLOy

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 554-559页

作者： G.S.Xie y.zeng H.Ding Hunan Electric Power Test & Research Institute Changsha 410007 ChinaMaterial Department Central South University Changsha 410083 ChinaMaterial Department Wuhan University Wuhan 430072 China

In this paper, the effect of RRA treatment on the microstructure evolution of a high strength aluminum alloy was investigated using DSC, TEM and SADP technology. The results show that the precipitation resulting from RRA is extremely fine and distributed homogeneously in the grains, being slightly coarser and more stable than that of T6 temper. While, the grain-boundary precipitation is very close to that of the alloy at T73 temper, being coarse and discontinuous. High retrogression temperature and long retrogression time leads to a more stable microstructure after re-aging.

关键词： DSC TEM RRA Al-Zn-Mg-Cu alloy

Electrodeposition mechanism of Ni-Mo-P alloy in the solution of ammoniac citrate

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Chinese Journal of Chemistry 1997年第3期15卷 193-200页

作者： zeng, y yao, SW Cao, XQ Huang, HX Zhong, Zy Guo, HT TIANJIN UNIV DEPT APPL CHEMTIANJIN 300072PEOPLES R CHINA

The induced codeposition mechanism of Mo, P and Ni from the solution of ammoniac citrate was studied by means of steady-state polarization, AC impedance and X-ray Photoelectron Spectroscopy (XPS). The result of electrochemical measurements proved that [NiCit(NH3)(2)](-) is the electro-active species of nickel, though nickel ions exist mainly as [NiCit(NH3)(3)](-) in ammoniac citrate. XPS experiments proved the existence of tetravalent molybdenum corresponding to MoO2 on the surface of some deposits. The intermediate product, MoO2, was probably reduced to Mo in the alloy deposit by atomic hydrogen adsorbed on the induced metal nickel. The reduction of H2PO2- occurs through two distinctive steps with PH3 as an, intermediate, which subsequently reacts with atomic hydrogen to form P in the alloy deposit. The electrodeposition mechanism was proposed in this paper.

关键词： Ni-Mo-P alloy electrodeposition mechanism

ATOMIZATION CAUSED By BOTTOM FLOW ENERGy DISSIPATION

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Journal of Hydrodynamics 2001年第1期13卷 23-27页

作者： Hu, M.L. Liang, Z.C. zeng, y.H. Wuhan Univ. of Hydraulic and Electr. Wuhan 430072 China

Bottom flow energy dissipation is one of the common energy dissipation methods for flood-releasing structures with high water head. Measures of this energy dissipation depend mainly on the turbulent action of hydraulic jump. In this paper, the physical process and the calculating methods of the atomization caused by bottom flow energy dissipation were studied, the computation models of atomization quantity for the self-aerated flow in overflow and hydraulic jump regions are presented, and the main results are of theoretical and practical significance for the hydraulic and electric engineering.

关键词： Energy dissipation Hydraulic jump Hydrodynamics

SIMULATION OF TEMPERATURE AND THERMAL STRESS FIELD IN LASER MILLING PROCESSING

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 43-46页

作者： G.F.yuan C.S.Ge X.y.zeng State Key Laboratory of Laser Technology.Huazhong University of Science and Technology Wuhan 430074China Anhui Institute of Architecture and IndustryHefei 230022 ChinaAnhui Institute of Architecture and IndustryHefei 230022 ChinaState Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China

The physical model of temperature field and thermal stress field are established in this paper, on which the numerical simulation with the assuming physical and laser milling parameters have been finished. The laser m... 详细信息

关键词： laser milling temperature field thermal stress field simulation

PHOTOCATALyTIC PERFORMANCE OF PLASMA SPRAyED TiO_2-ZnFe_2O_4 COATINGS

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 363-368页

作者： y.zeng J.T.Liu W.J.Qian J.H.Gao ShanghaiInstituteofCeramics TheChineseAcademyofSciencesShanghai200050China

A novel TiO2-ZnFe2O4 coating is prepared by plasma spraying. The effects of spra ying parameters and the composition of powders on the microstructure, surface mo rphology and photo-absorption of plasma sprayed coatings are studied. The photoc atalytic efficiency of the as-sprayed coatings is evaluated through the photo mi neralization of methylene blue. It was found that TiO2 coatings can decompose me thylene blue under the illumination of ultraviolet rays, and the degrading effic iency is improved with an increase in the content of FeTiO3 in the coatings. How ever, the presence of large amount of ZnFe2O4 compound will substantially lower the photocatalytic efficiency of the TiO2-ZnFe2O4 coatings for the unfavorable p hoto-excited electron-hole transfer process.

关键词： plasma spraying photocatalytic activity TiO2 ZnFe2O4

SyNTHESIS　AND　ANTI－HIV－1　ACTIVITy　OF　HETEROPOLy　COMPLEXES　OF　TUNGSTOTITANOPHOSPHATES　CONTAINING　RARE　EARTH　ELEMENTS

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Chinese Chemical Letters 1996年第8期7卷 777-778页

作者： Liu, SX Li, BT Wang, L Liu, yy Wang, EB zeng, y Li, ZL NE NORMAL UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA CHINESE ACAD PREVENT MED BEIJING 100050PEOPLES R CHINA

The present paper rePOrts nine new heteropoly compounds of tungstotitanophosphates containing rare earth elements, i. e., Ln2H[PTi2W10O40]. xH2O (Ln=La,Ce, Pr, Nd, Sm, Gd, Tb, yb, Lu). The above compounds have shown g... 详细信息

关键词： HIV-1

Interaction of Aromatic Hydrocarbons with Sulfuric Acid,Bisulfate and Sulfate Anions

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1091-1097页

作者： ZHAO ya-ying zeng Eddy y ZHANG Xi-Hui MA Lin TAO Fu-Ming Research Center of Environmental Engineering and Management Graduate School at Shenzhen. Tsinghua University. Shenzhen 518055 China State Key Laboratory of Organic Geochemistr). Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Department of Chemistry and Biochemistry California State University Fullerton CA 92834 USA

Intermolecular geometries and energies of the dimers formed between simple aromatic hydrocarbons （benzene, toluene and naphthalene） and sulfate species （sulfuric acid, bisulfate and sulfate） were studied by density functional theory. The AH：H2SO4 complexes were determined by the OH-π H-bond, with H2SO4 acting as the H-bond donor and AHs as the aeeeptor. However, the AHs：HSO4- and AHs：SO4^2- complexes were established by the H-bond, with AHs serving as acid and HSO4 or SO4^2- as alkali. The atmospheric implications of those complexes were strongly supported by their considerable binding energies.

关键词： PAHs sulfate species interaction density functional theory

STUDy OF MICROSTRUCTURES OF DEFORMED Ti-48Al-Mn-Nb ALLOy

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Acta Metallurgica Sinica(English Letters) 1996年第4期9卷 267-271页

作者： D Song,G.y zeng and X. y Sun (Material Testing Centre, Northeastern University,Shenyang 110006,China )

In the present paper, the microstructures of the two-phase alloy specimens of Ti-48AlMn-Nb, deformed at room temperature, 700℃and 900℃,have been investigated by using an EM400T transmission electron microscope. For specimens deformed at room temperature it is observed that (1/2) [011] superdislocation, normal (1/2) [110] dislocations, stacking fault band and a few twins etc. formed mainly in r-phase and a (1/2) [011] superdislocation preferentially decomposes into two partial dislocations with an antiphase boundary between them, which makes the dislocation difficult to move. The normal (1/2) [110] dislocations move with a long dragging tail behind them and have a low mobility In addition, the existence of a few twins implies a low mobility of (1/6) twin dislocations, which leads to low plasticity of the allow. For samples deformed above 700℃,(1/2) [110] dislocations are in majority in the r-phase and exhibit short and bending dislocation segments without dragging tails,which may have resulted from an increased mobility of (1/2) [110] dislocations due to thermal activation. Meanwhile, (1/2) [011]superdislocation disappears, the mobility of (1/6) dislocations is greatly increased, and thus a lot of twins are produced in r-phase. These make the plasticity of the alloy notably enhanced. The laminated structures in the alloy may be transformed into stacking fault bands during deformation at room temperature and the deformation above 700℃leads to the generation of a great quantity of twins.

关键词： dislocation stacking fault twin TiAl alloy