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Acta Mechanica Solida Sinica 1997年第1期10卷 86-94页

作者： zhuang, z ODonoghue, PE TSING HUA UNIV DEPT ENGN MECHBEIJING 100084PEOPLES R CHINA NATL UNIV IRELAND UNIV COLL DUBLIN DEPT CIVIL ENGNDUBLIN 2IRELAND

In the light of a growing need for fracture control of rapid crack propagation (RCP) in gas pipelines, a program PFRAC(Pipeline FRacture Analysis Code) has been developed((1)) to analyse the various events. In this paper, by using PFRAC for the simulation of axial crack propagation in gas pipelines, a number of dynamic analysis issues relating to boundary effects for uncracked and cracked pipes are investigated. This indicates that the boundary conditions along the length of the pipe play an important role for fracture analysis in the pipe. In contrast, the boundary conditions at the ends of a long pipeline have little effect on the dynamic fracture events.

关键词： fracture mechanics finite element pipe boundary condition

Revealing the high-frequency attenuation mechanism of polyurea-matrix composites

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Acta Mechanica Sinica 2020年第1期36卷 130-142页

作者： J.Cheng z.L.Liu C.C.Luo T.Li z.J.Li Y.Kang z.zhuang Applied Mechanics Laboratory School of Aerospace EngineeringTsinghua UniversityBeijing100084China Key Laboratory of Advanced Materials of Ministry of Education Department of Chemical EngineeringTsinghua UniversityBeijing100084China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China

In this paper,a method for analyzing the high-frequency attenuation property of polyurea-matrix composites is developed by combining experimental,computational and theoretical ***,the ultrasonic experimental platform is established by solving the difficulties of high-frequency ultrasonic testing as high-frequency signal distortion,insufficient driving voltage and sampling rate failure,to study the dynamic mechanical properties(1-5 MHz)of pure polyurea and polyurea-matrix ***,the influences of composite parameters including the size and volume fraction of inclusions on wave attenuation performance under different frequencies are obtained and further verified by numerical ***,the contribution of inclusions to the wave attenuation performance is also theoretically *** is found that the increase of inclusion volume fraction and inclusion diameter will increase the attenuation coefficient of the *** the attenuation of composites with the inclusions of a 150-μm diameter and 30%as volume fraction can be 82%higher than pure *** amplifying attenuation effect of inclusions is mainly attributed to the scattering effect,which is verified by comparing numerical and theoretical results.

关键词： Polyurea Viscoelastic Dynamic mechanical properties Ultrasound

Tailoring precipitation/properties and related mechanisms for a high-strength aluminum alloy plate via low-temperature retrogression and re-aging processes

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Journal of Materials Science & Technology 2022年第25期120卷 15-35页

作者： L.G.Hou H.Yu Y.W.Wang L.You z.B.He C.M.Wu D.G.Eskin L.Katgerman L.z.zhuang J.S.zhang State Key Laboratory for Advanced Metals&Materials University of Science&Technology BeijingBeijing 100083China BCAST Brunel University LondonKingston LaneUxbidge Middlesex UB83PHUnited Kingdom Institute of mineral resources Chinese Academy of Geological SciencesBeijing 100037China Nanjing Advanced Transportation Equipment New Technology Research Institute Nanjing 211800China Tomsk State University Tomsk634050Russian Federation Katgerman Aluminium Technology van Beuningenlaan 102334CC LeidenNetherlands Department of Materials Science and Engineering Delft University of TechnologyMekelweg 22628CD Delftthe Netherlands

The retrogression and re-aging(RRA)processes,aimed mainly at tailoring intergranular precipitates,could significantly improve the corrosion resistance(i.e.,stress corrosion cracking resistance)without considerably decreasing the strength,which signifies that an efficient control of the size,distribution and evolution of intergranular and intragranular precipitates becomes critical for the integrated properties of the(mid-)thick high-strength Al alloy *** to RRA process with retrogression at200℃ (T77),this study investigated the impact of a modified RRA process(MT77)with lower retrogression temperatures(155-175℃ )and first-stage under-aging on the properties of a high-strength AA7050 Al alloy,in combination with detailed precipitate *** study showed that the strength/microhardness of the RRA-treated alloys decreased with raising retrogression temperature and/or prolonging retrogression time,along with the increased electrical *** rapid responsiveness of microstructure/property typical of retrogression at 200℃ was obviously postponed or decreased by using MT77 process with longer retrogression time that was more suitable for treating the(mid-)thick *** the other hand,higher retrogression temperature facilitated more intragranularηprecipitates,coarse intergranular precipitates and wide precipitate free zones,which prominently increased the electrical conductivity alongside a considerable strength loss as compared to the MT77-treated *** the preferred MT77 process,the high strength approaching T6 level as well as good corrosion resistance was ***,though a relatively homogeneous through-thickness strength was obtained,some small discrepancies of properties between the central and surface areas of an 86-mm thick 7050 Al alloy plate were observed,possibly related to the quenching *** precipitate evolution and mechanistic connection to the properties were discussed and reviewed for high-strengt

关键词： Aluminum alloy Heat treatment Precipitation Strength Grain boundary

Synergistic effect of gradient zn content and multiscale particles on the mechanical properties of Al-zn-Mg-Cu alloys with coupling distribution of coarse-fine grains

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1392-1405页

作者： Liangliang Yuan Mingxing Guo Yi Wang Yun Wang Linzhong zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0zn–1.5Mg–1.5Cu–0.2Fe(wt%)alloy with high strength and *** the increase of zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is *** phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to *** reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the *** developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–zn–Mg–Cu alloys.

关键词： Al–zn–Mg–Cu alloy iron-rich phase high formability microstructure mechanisms

Understanding the initial use stage of cement mortar lining in drinking water distribution systems:Silicon and aluminum as stability indicators

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Journal of Environmental Sciences 2024年第1期135卷 495-505页

作者： Qiaozhi Liu Yuan zhuang Guiwei Li Yao zhang Marc A.Edwards Baoyou Shi Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Civil and Environmental Engineering Virginia TechBlacksburgVA 24061USA

The cement mortar lining(CML)of commonly used ductile iron pipes can severely deteriorate the drinking water quality at the initial stage of use,but the behavioral characteristics of different elements release from the CML in this stage is still *** this study,dynamic immersion experiments with new cement mortar lined ductile iron pipe reactors were conducted under different feed water hardness and alkalinity *** results showed that the release of alkaline substances from the CML at the initial stage of use could strongly influence the pH of water,which consequently greatly impacted the release/precipitation behaviors of calcium,aluminum and *** pH and aluminum concentration of the effluent water could reach 11.5 and 700μg/L within 24 hr of hydraulic retention time,respectively,under conditions of relatively lower hardness and *** to the pH elevation,calcium carbonate precipitation could occur even at much lower feed water *** the aluminum and silicon could keep release from the CML in soluble form at different hardness and alkalinity levels,and their release rate depended on the amount of calcium carbonate ***,aluminum and silicon were more suitable as indicators of the corrosion intensity at the initial stage of CML use rather than the traditional calcium carbonate precipitation *** feed water hardness and alkalinity levels for mitigating the initial intense corrosion of CML were proposed:hardness>40 mg/L(CaCO_(3)),alkalinity>100 mg/L(CaCO_(3)).

关键词： Cement mortar lining Hardness Alkalinity Elemental release Drinking water supply

High-order time-reversal symmetry breaking normal state

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： Meng zeng Lun-Hui Hu Hong-Ye Hu Yi-zhuang You Congjun Wu Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA Department of Physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional *** two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap *** contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is *** phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is *** θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal *** both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry *** employ an effective two-component XY-model assisted by a renormalization group analysis to address this *** a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)*** is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature z_(2)-breaking charge-2e superconducting *** results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

Molecular Mapping of Three Loci Conferring Resistance to Maize (zea mays L.) Rough Dwarf Disease

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分子植物育种 2007年第2期5卷 178-179页

作者： F. Wang　 Y.S. zhang　 Y.L. zhuang　 G.z. Qin　 J.R. zhang School of Life Science Shandong University Jinan 250100 China

Maize rough dwarf disease (MRDD) is a viral disease that is widely distributed in the world and causes great losses in grain yield. During the past three decades, considerable progress has been made in the

关键词：玉米疾病农作物分子机制

Understanding the role of manganese oxides in retaining harmful metals: Insights into oxidation and adsorption mechanisms at microstructure level

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Eco-Environment & Health 2024年第1期3卷 89-106页

作者： Feng Li Hui Yin Tianqiang zhu Wen zhuang School of Environmental Science and Engineering Shandong UniversityQingdaoShandong 266237China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtse River) Ministry of Agriculture and Rural AffairsCollege of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070China State Environmental Protection Key Laboratory of Soil Health and Green Remediation Ministry of Ecology and EnvironmentHuazhong Agricultural UniversityWuhan 430070China National Laboratory for Marine Science and Technology Qingdao 266237China Institute of Eco-environmental Forensics Shandong UniversityQingdao 266237China

The increasing intensity of human activities has led to a critical environmental challenge:widespread metal ***(Mn)oxides have emerged as potentially natural scavengers that perform crucial functions in the biogeochemical cycling of metal *** reviews have focused on the synthesis,characterization,and adsorption kinetics of Mn oxides,along with the transformation pathways of specific layered Mn *** review conducts a meticulous investigation of the molecular-level adsorption and oxidation mechanisms of Mn oxides on hazardous metals,including adsorption patterns,coordination,adsorption sites,and redox *** also provide a comprehensive discussion of both internal factors(surface area,crystallinity,octahedral vacancy content in Mn oxides,and reactant concentration)and external factors(pH,presence of doped or preadsorbed metal ions)affecting the adsorption/oxidation of metals by Mn ***,we identify existing gaps in understanding these mechanisms and suggest avenues for future *** goal is to enhance knowledge of Mn oxides'regulatory roles in metal element translocation and transformation at the microstructure level,offering a framework for developing effective metal adsorbents and pollution control strategies.

关键词： Manganese oxides Harmful metals Adsorption Redox Environment

Electrochemical converting ethanol to hydrogen and acetic acid for large scale green hydrogen production

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Nano Research 2024年第3期17卷 1542-1551页

作者： Yufeng zhang Wei zhu Jinjie Fang zhiyuan Xu Yanrong Xue Jiajing Pei Rui Sui Xingdong Wang Xuejiang zhang zhongbin zhuang State Key Lab of Organic-Inorganic Composites and Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Laboratory of Advanced Functional Materials of Nanjing Nanjing Xiaozhuang UniversityNanjing 211171China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China

Electrochemical coupling hydrogen evolution with biomass reforming reaction(named electrochemical hydrogen and chemical cogeneration(EHCC)),which realizes green hydrogen production and chemical upgrading simultaneously,is a promising method to build a carbon-neutral ***,we analyze the EHCC process by considering the market *** ethanol to acetic acid and hydrogen approach is the most feasible for large-scale hydrogen *** develop AuCu nanocatalysts,which can selectively oxidize ethanol to acetic acid(>97%)with high long-term *** isotopic and in-situ infrared experiments reveal that the promoted water dissociation step by alloying contributes to the enhanced activity of the partial oxidation reaction path.A flow-cell electrolyzer equipped with the AuCu anodic catalyst achieves the steady production of hydrogen and acetic acid simultaneously in both high selectivity(>90%),demonstrating the potential scalable application for green hydrogen production with low energy consumption and high profitability.

关键词： selective ethanol electrooxidation gold alloy catalyst electrochemical-coupled hydrogen production market assessment interfacial water activation

Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm_(2)Co_(17)-type magnet

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Rare Metals 2024年第4期43卷 1724-1735页

作者： zhuang Liu Hai-Chen Wu Chao-Yue zhang Chao-Qun zhu Guo-Xin Chen Huan-Ming Lu Ren-Jie Chen Aru Yan CISRI&NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of Sciences Beijing100049China Analytical Center Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China

Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(17)-type magnet,which is a key factor limiting the further improvement of magnetic energy *** this study,we report that nanoscale strip-like ordered micro-domains distributed in1:7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary *** strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering *** solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1:7H(TbCu_(7)-type structure)phase between the separated strip-like ordered *** disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the ***,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is *** boundaries enriched in Cu have already existed in the precursor with long strip-like ordered ***,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm_(2)Co_(17)-type *** results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the key factor improving the distribution of cell boundary phase in Sm_(2)Co_(17)-type magnets.

关键词： Sm_(2)Co_(17) magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure