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Semisolid die forging process,microstructures and properties of AZ31 magnesium alloy mobile telephone shells

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 665-670页

作者： Ren-guo Guan li-qing Chen Fu-rong cao Zhan-yong Zhao yong Ren College of Materials and Metallurgy Northeastern University Shenyang 110004 China State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 China

A semisolid slurry of AZ31 magnesium alloy was prepared by vibrating wavelike sloping plate process,and the semisolid die forging process,microstructures,and properties of the magnesium alloy mobile telephone shell were *** semisolid forging process was performed on a YA32-315 four-column universal hydraulic *** microstructures were observed by optical microscopy,the hardness was analyzed with a model 450SVD Vickers hardometer,the mechanical properties was measured with a CMT5105 tensile test machine,and the fractograph of elongated specimens was observed by scanning electron microscopy （SEM）.The results reveal that with the increase of die forging force,the microstructures of the product become fine and dense.A lower preheating temperature and a longer dwell time are favorable to the formation of fine and dense *** optimum process conditions of preparing mobile telephone shells with excellent surface quality and microstructures are a die forging force of 2000 kN,a die preheating temperature of 250℃,and a dwell time of 240 *** solution treatment at 430℃ and aging at 220℃ for 8 h,the Vickers hardness is 61.7 and the ultimate tensile strength of the product is *** fractographs show the mixing mechanisms of quasi-cleavage fracture and ductile fracture.

关键词： magnesium alloys semisolid forging microstructure mechanical properties fracture

Highly Chemoselective Reduction of Nitroarenes Using a Titania-Supported Platinum-Nanoparticle Catalyst under a CO Atmosphere

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Chinese Journal of Chemistry 2017年第5期35卷 591-595页

作者： Shushuang li Fuzerong Wang yongmei liu yong cao Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 China

The discovery that supported gold catalysts can promote CO/H2O-mediated reduction at ambient temperatures is important to chemoselective synthesis and has gained significant attention in recent *** the alternative Pt group metal （PGM） catalysts can exhibit such exceptional performance is thus an interesting research *** far,no PGM catalyst shows activity for CO/H2O-mediated reduction at ambient ***,we demonstrate that it is possible to transform nonactive into highly active and selective catalysts for CO/H2O-mediated reduction by modulating the interfacial structure and electronic properties at the metal-support ***,highly active and chemoselective hydrogenation Pt,Ir,Rh and Pd catalysts can be prepared by decorating the exposed metal faces with partially reduced support species by means of a simple catalyst activation *** this way,it has been possible to dramatically facilitate the previously unappreciated PGM-catalyzed activation of CO molecules under mild conditions,which can make a significant contribution not only to reveal the intrinsic catalytic potential of supported PGMs but also to establish a more sustainable and industrially-relevant process.

关键词： nitroarenes reduction carbon monoxide PGM catalysts strong metal-support interactions

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日本知识界认知中的五四运动

河北学刊 2025年第1期45卷 210-217页

作者：曹萌中国社会科学院

五四运动爆发后,日本主流舆论将其定性为“排日运动”,多指责中国青年学生排斥日本,认为英美势力与中国亲英美派政客煽动青年学生促成了“暴动”。部分日本在华媒体人和以吉野作造为代表的日本新知识分子以及大阪报刊《大正日日新闻》... 详细信息

五四运动爆发后,日本主流舆论将其定性为“排日运动”,多指责中国青年学生排斥日本,认为英美势力与中国亲英美派政客煽动青年学生促成了“暴动”。部分日本在华媒体人和以吉野作造为代表的日本新知识分子以及大阪报刊《大正日日新闻》却肯定了五四运动体现出的进步思想,呼吁日本民众理性看待中国的民众运动。其中,《大正日日新闻》1920年新年号连载“中国名士之对日意见”,这些意见集中介绍了五四运动、新思想运动的真义,体现了五四运动后日本知识界对中国新思想的关注,同时也呈现出日本对华观的多面性与复杂性。

关键词：五四运动中日关系吉野作造《大正日日新闻》

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期 206-222页

作者： YANG Jianwen CHEN Wei cao Bingwei liU Xinhui li Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

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Dynamic deformation behavior of a FeCrNi medium entropy alloy

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Journal of Materials Science & Technology 2022年第5期100卷 120-128页

作者： Ao Fu Bin liu Zezhou li Bingfeng Wang Yuankui cao yong liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoUnited States School of Materials Science and Engineering Central South UniversityChangsha 410083China

Deformation behavior of a FeCrNi medium entropy alloy(MEA)prepared by powder metallurgy(P/M)method was investigated over a wide range of strain *** FeCrNi MEA exhibits high strain-hardening ability,which can be attributed to the multiple deformation mechanisms,including dislocation slip,deformation induced stacking fault and mechanical *** shear localization behavior of the FeCrNi MEA was also analyzed by dynamically loading hat-shaped specimens,and the distinct adiabatic shear band cannot be observed until the shear strain reaches~*** microstructures within and outside the shear band exhibit different characteristics:the grains near the shear band are severely elongated and significantly refined by dislocation slip and twinning;inside the shear band,the initial coarse grains completely disappear,and transform into recrystallized ultrafine equiaxed grains by the classical rotational dynamic recrystallization ***,microvoids preferentially nucleate in the central areas of the shear band where the temperature is very high and the shear stress is highly *** microvoids will coalesce into microcracks with the increase of strain,which eventually leads to the fracture of the shear band.

关键词： Medium entropy alloys Mechanical response Dynamic shear properties Grain refinement Adiabatic shear band

Microstructure of Fe-Based Alloy Composite Coatings Reinforced by Ti(C_(0.3)N_(0.7)) Particles Through Laser Cladding Technology

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Journal of Iron and Steel Research International 2013年第8期20卷 78-82页

作者： QI yong-tian cao Zhao-xia SHENG li-ying cao Run-ping Inner Mongolia Baotou Vocational and Technical College

Fe-based alloy layer reinforced by Ti（C,N） particles was produced on the surface of cast steel. X ray dif fraction （XRD） was used for phase identification in the composite coating. The microstructure of laser cladding layer was analyzed by means of optical microscope （OM）, electron probe microscope analyzer （EPMA）, scanning electron microscope （SEM） and transmission electron microscope （TEM）. The results show that Ti（C0.3 N0.7 ） particle is in-troduced by an in situ metallurgical reaction of TiN particle and graphite powder in the process of laser cladding. The shape of lots of Ti（C0.3 N0.7） particle is irregular. The sizes of Ti（C0. 3N0. 7） particles range from 0. 1 to 6.0 μm, and they are dispersed evenly in the matrix, which is fine dendritic or cellular crystal. A new kind of phase named Ti（C0.3 N0. 7 ） parti-cles are tightly bonded with α-Fe microstructure, and there is a clean and smooth phase interface between ceramic re-inforcement phase and the matrix.

关键词： Ti(C0.3 N0.7 ) particle TiN laser cladding microstructure

Synthesis of two-dimensional π-conjugated polymers pendent with benzothiadiazole and naphtho[1,2-c:5,6-c]bis[1,2,5]thiadiazole moieties for polymer solar cells

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Science China Chemistry 2015年第2期58卷 257-266页

作者： Wei li Qingduan li Shengjian liu Chunhui Duan Lei Ying Fei Huang yong cao Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology

Four new 2D donor–acceptor conjugated polymers were designed and *** new polymers comprised fluorenealt-triphenylamine or carbazole-alt-triphenylamine as the backbones,and pendants with 2,1,3-benzothiadiazole(BT)or naphtho[1,2-c:5,6-c]bis[1,2,5]thiadiazole(NT)in a triphenylamine unit as the side *** changing the acceptor BT for a stronger electron-withdrawing unit of NT moiety in the side chain,the energy levels,absorption spectra,band gaps,and charge-transport abilities of the resultant polymers could be effectively *** heterojunction solar cells with these polymers as the electron donors and(6,6)-phenyl-C71-butyric acid methyl ester as the electron acceptor exhibited high open-circuit voltage(more than 0.8 e V).The power conversion efficiency can be improved from 1.37%to 3.52%by replacing the BT with an NT moiety,which indicates that introducing NT as the side-chain building block can be an effective strategy to construct efficient 2D conjugated polymers for PSCs.

关键词： two-dimensional conjugated polymer benzothiadiazole naphthobisthiadiazole bulkheterojunction polymer solar cell

Effects of sodium-glucose cotransporter 2 inhibitors on cardiovascular outcomes in elderly patients with comorbid coronary heart disease and diabetes mellitus

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Journal of Geriatric Cardiology 2021年第6期18卷 440-448页

作者： Hu XU Wen-Zhe cao yong-Yi BAI Rui-Hua cao Lei TIAN Feng cao li FAN Chinese PLA Medical School Chinese PLA General HospitalBeijingChina Department of Cardiology the Second Medical CenterNational Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijingChina Institute of Geriatrics the Second Medical CenterChinese PLA General HospitalBeijingChina

OBJECTIVE To investigate the effects of sodium-glucose cotransporter 2 inhibitors(SGLT2i)on cardiovascular outcomes in elderly Chinese patients with comorbid coronary heart disease(CHD)and type 2 diabetes mellitus(T2DM).METHODS A retrospective cohort study was conducted on 501 elderly inpatients(≥60 years)with comorbid CHD/T2DM in Department of Cardiovascular Medicine and Endocrinology,Chinese PLA General Hospital from January 2018 to December *** patients were divided into two groups according to the administration of *** the demographic characteristics and clinical data were *** outcomes,including all-cause mortality,major adverse cardiovascular events(MACE),and hospitalization for heart failure(HHF),were followed *** In the cohort,there were 167 patients in the SGLT2i group and 334 patients in the control *** the efficacy analyses,the incidence of MACE was lower in the SGLT2i group than in the control group:3.6%vs.9.3%(P=0.022).A lower risk of MACE was observed in the SGLT2i group[hazard ratio(HR)=0.40,95%CI:0.17-0.95].There was no significant difference in the incidence of all-cause mortality or HHF between the two *** significant difference of HR was observed for all-cause mortality(HR=0.41,95%CI:0.12-1.41)or HHF(HR=0.58,95%CI:0.12-2.81).CONCLUSIONS SGLT2i treatment exhibited benefits for elderly patients with comorbid CHD/T2DM with a lower risk for MACE.

关键词： patients morbid mortality

Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao XIA Jianing liANG Yuhao JIANG Zhiyang PENG Jiaxu li Chen XIAO Renyou XU Wenwen WANG Xiantao SHANG Shiyang LU Dapeng ZHU Hong-Xi liU Kaihua cao Weisheng ZHAO Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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