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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.y.yue s.y.peng X.Zhang C.N.He y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China school of Materials science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution treated.The hot-pressed sintered and solution treated materials were rolled and aged.The precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron microscopy.In contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe composite.The Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACs and softening temperature of 838 K.Mechanisms for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were analyzed.These findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability strength Electrical conductivity

synergistic O^(2-)/Li^(+) Dual Ion Transportation at Atomic scale

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Research 2019年第1期2019卷 1260-1267页

作者： F.Q.Meng Q.H.Zhang A.Gao X.Z.Liu J.N.Zhang s.y.peng X.Lu L.Gu H.Li Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China school of Materials Sun Yat-Sen UniversityGuangzhou 510275China College of Materials science and Engineering Jiangxi University of Science and TechnologyJiangxi 341000China songshan Lake Materials Laboratory DongguanGuangdong 523808China school of Physical sciences University of Chinese Academy of SciencesBeijing 100049China

Te ion migration during electrochemical process is a fundamental scientifc issue for phase transition behavior and of technical importance for various functional devices,where cations or anions are active under electrical bias.Usually only one type of functional ion,O^(2-)or Li^(+),is activated due to their diferent migration energy barriers,cooperated by the valence change of other immobile ions in the host lattice matrix,e.g.,Co^(2+)/Co^(3+)and Mn^(3+)/Mn4+redox couples,owing to the charge neutralization.Here we select spinel Li4Ti5O12 as anode and construct an all-solid-state battery under a transmission electron microscope;a synergistic transportation of O^(2-)and Li^(+)driven by an electrical bias was directly observed at the atomic scale.A small amount of oxygen anions was extracted frstly as a result of its lowest vacancy formation energy under 2.2 V,leading to the vertical displacement of oxygen.Up to 2.7 V,an ordered phase with both Li-and O-defciency formed.Te Li^(+)and O^(2-)ions are simultaneously extracted out from the[LiO_(4)]tetrahedra due to the electroneutrality principle.Te migration paths of O and Li have been proposed and verifed by frst-principles calculations.Tese results reveal a brand new synergistic ion migration manner and may provide up-to-date insights on the transportation process of lithium ion conductors.

关键词： synergistic battery migration

Application of improved AHP method and variable weight theory to rock mass quality evaluation

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Application of improved AHP method and variable weight theor...

Ren-integrable and ren-symmetric integrable systems

The 2nd IsRM International young scholars’symposium on Rock Mechanics

作者： s.y.peng G.J.Li s.W.Qin & J.Q.Ma College of Construction Engineering Jilin University Jilin Province China

Rock quality evaluation is a multi-factor integrated decision-making problem.It is crucial to determine the weight of factors in the process of evaluation.Result of constant weight model may not co

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Communications in Theoretical Physics 2024年第3期76卷 62-69页

作者： s y Lou school of Physical science and Technology Ningbo UniversityNingbo315211China

A new type of symmetry,ren-symmetry,describing anyon physics and corresponding topological physics,is proposed.Ren-symmetry is a generalization of super-symmetry which is widely applied in super-symmetric physics such as super-symmetric quantum mechanics,super-symmetric gravity,super-symmetric string theory,super-symmetric integrable systems and so on.supersymmetry and Grassmann numbers are,in some sense,dual conceptions,and it turns out that these conceptions coincide for the ren situation,that is,a similar conception of ren-number(R-number)is devised for ren-symmetry.In particular,some basic results of the R-number and ren-symmetry are exposed which allow one to derive,in principle,some new types of integrable systems including ren-integrable models and ren-symmetric integrable systems.Training examples of ren-integrable KdV-type systems and ren-symmetric KdV equations are explicitly given.

关键词： symmetries integrable systems anyon physics extended supersymmetry ren-symmetry

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction method.The red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission significantly.This improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

Electronic origin of structural degradation in Li-rich transition metal oxides:The case of Li_(2)MnO_(3)and Li_(2)RuO_(3)

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Journal of semiconductors 2024年第4期45卷 82-86页

作者： peng Zhang Key Laboratory of Optoelectronic Devices and systems of Ministry of Education and Guangdong Province College of Physics andOp toelec-tronic EngineeringShenzhen UniversityShenzhen 518060China

Li_(2)MnO_(3)and Li_(2)RuO_(3)represent two prototype Li-rich transition metal(TM)oxides as high-capacity cathodes for Li-ion batteries,which have similar crystal structures but show quite different cycling performances.Here,based on the first-princi-ples calculations,we systematically studied the electronic structures and defect properties of these two Li-rich cathodes,in order to get more understanding on the structural degradation mechanism in Li-rich TM oxides.Our calculations indicated that the structural and cycling stability of Li_(2)MnO_(3)and Li_(2)RuO_(3)depend closely on their electronic structures,especially the energy of their highest occupied electronic states(HOs),as it largely determines the defect properties of these cathodes.For Li_(2)MnO_(3)with low-energy HOs,we found that,due to the defect charge transfer mechanism,various defects can form spontaneously in its host structure as Li ions are extracted upon delithiation,which seriously deteriorates its structural and cycling stability.While for Li_(2)RuO_(3),on the other hand,we identified that the high-energy HOs prevents it from the defect formation upon delithi-ation and thus preserve its cycling reversibility.Our studies thus illustrated an electronic origin of the structural degradation in Li-rich TM oxides and implied that it is possible to improve their cycling performances by carefully adjusting their TM compo-nents.

关键词： defects Li-ion batteries first-principles calculations

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/Cds heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials science & Technology 2024年第4期171卷 1-9页

作者： T.y.Huang Z.yang s.y.yang Z.H.Dai y.J.Liu J.H.Liao G.y.Zhong Z.J.Xie y.P.Fang s.s.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China school of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China school of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic reactions.Constructing photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor materials.Herein,a novel stable Ti_(3)C_(2)T_(x)MXene/Cds heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)Cds nanosheets on 2D MXene interface via a solvothermal method.The exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous catalyst.The unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the catalyst.Moreover,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of Cds.Under irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of Cds catalyst.This study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

Accelerated water harvesting from vapor via a bio-inspired hydrogel pattern

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National science Review 2024年第3期11卷 48-49页

作者： Lianbin Zhang peng Wang state Key Laboratory of Material Processing and Die&Mould Technology Key Laboratory of Materials Chemistry for Energy Conversion and Storage of Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology(HUST) school of Environmental science and Engineering Sun Yat-sen University

Water and energy sustainability are integral parts of resource sustainability of the world. Due to water molecules' superior capability of serving as both hydrogenbond donor and acceptor, phase change of water, especially between liquid and vapor, underpins global water cycles,facilitates energy transformation and transfer, and thus helps shape the unique local weather and global climate patterns.

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Time-Periodic solutions to Quasilinear Hyperbolic systems on General Networks

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Chinese Annals of Mathematics,series B 2024年第1期45卷 41-72页

作者： peng QU school of Mathematical sciences Fudan UniversityShanghai 200433China

For quasilinear hyperbolic systems on general networks with time-periodic boundary-interface conditions with a dissipative structure,the existence and stability of the time-periodic classical solutions are discussed.

关键词： Time-periodic solution Quasilinear hyperbolic system General net-work Classical solution Asymptotic stability

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun Gao yan peng school of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting process.The effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in detail.In each rotation,the casting wheel passes through four different spray zones.The results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,respectively.The temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones