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Journal of Magnesium and Alloys 2021年第3期9卷 818-828页

作者： l.y.zhao H.yan R.S.Chen En-Hou Han The Group of Magnesium Alloys and Their Applications Institute of Metal ResearchChinese Academy of Sciences62 Wencui RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China

The grain growth process plays an important role in the texture formation in magnesium *** microstructural and micro-textural evolution of a cold-rolled Mg-Zn-Gd alloy during annealing at 350℃for 60-190 min were tracked by quasi-in-situ electron backscatter diffraction *** results show that grain growth takes place gradually with the annealing time ***,the TD-split texture maintains the texture type but alters in three aspects-the increased tilting angle,the decreased pole intensity and the widened distribution of high-intensity *** with their c-axis tilting 45-70°from normal direction show preferential growth which is closely associated with the texture *** original grain size advantage is one of the important factors leading to the growth advantage,some grain boundaries,such as 50-60°[1^(-)21^(-)0],50-60°[2750],60-70°[1^(-)21^(-)0](18b),and 70-80°[1^(-)01^(-)0](10)are also considered to be related to this preferential growth.

关键词： Grain growth Preferential growth Texture Static recrystallization Magnesium alloys

Orientations of nuclei during static recrystallization in a cold-rolled Mg-Zn-Gd alloy

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Journal of Materials Science & Technology 2021年第1期60卷 162-167页

The static recrystallization process of a cold-rolled Mg-Zn-Gd alloy was tracked by a quasi-in-situ electron backscatter diffraction method to investigate the orientations of *** results show that orientation distribution of nuclei is associated with nucleation *** continuous static recrystallization nuclei display similar orientations to the parent grains with TD ***,discontinuous static recrystallization nuclei formed within the parent grains(TD-45~0 orientation) show random orientations and a variety of misorientation angles but preferred axes or .Interestingly,a special oriented nucleation is *** static recrystallization nuclei originated from boundaries of the parent grain(TD-70° orientation) show concentrated TD orientations in another side due to the preferred misorientation relationship 70°(∑18 b).It is speculated that these two special misorientation relationships are related to the dislocation type.

关键词： Mg alloys Orientation Nucleation Quasi-in-situ EBSD Static recrystallization

Reduction effect of final-pass heavy reduction rolling on the texture development,tensile property and stretch formability of ZWK100 alloy plates

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Journal of Materials Science & Technology 2022年第16期111卷 211-223页

作者： B.Q.Shi l.y.zhao X.l.Shang B.H.Nie D.C.Chen C.Q.li y.Q.Cheng School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China School of Materials and Energy Guangdong University of TechnologyGuangzhouGuangdong 510006China GD Midea Air-Conditioning Equipment Co. Ltd.Foshan 528311China Guangdong Key laboratory of Hydrogen Energy Technology Foshan 528000China yunFu(Foshan)R&D Center of Hydrogen Energy Standardization Yunfu 527326China

Obviously planar anisotropy due to‘TD split’orthotropic texture(TD indicates Transverse direction)always exist in the Rare-earth(RE)or Ca containing Mg alloy sheets,which is likely caused by the lowreduction rolling(and annealing)as revealed in our previous *** this work,the as-cast billets of a ZWK100 alloy were subjected to final-pass heavy reduction rolling(FHRR)at 500°C with different reductions(30%-70%)after rough rolling,aiming to investigate the reduction effect on the microstructure and texture *** results show that FHRR with higher reductions above 50%is in favor of shear banding formation but has little effect on the as-deformed texture components,and the excellent formability with single-pass reduction up to 70%is mainly ascribed to the activation of prismatic *** with reduction above 50%and annealing can generate uniform grain structures of~10μm and symmetrical‘oblique-line split’texture in(0001)pole figures,with basal poles tilting by about 50°from ND(Normal direction)towards some oblique-line of TD and RD(Rolling direction)as well as uniform distribution of counter lines as an annular shape,resulting in excellent elongation to failure of~50%and ultra-low planar anisotropyΔr_of~0.1 and high stretch formability(Erichsen value:8.1).The formation‘oblique-line split’texture in(0001)pole figures is mainly correlated with the preferred growth tendency of grains with■//RD,which was suggested to relate to the high mobility of some special boundaries such as 40°-45°■.The influences of starting textures on the mechanical properties,planar anisotropy and related deformation modes,as well as their correlations with the stretch formability were comparatively investigated with the‘TD split’orthotropic texture as a counterpoint.

关键词： Magnesium alloys Texture Plane anisotropy Stretch formability Rolled sheets

Combined approach for analysing evolutionary power spectra of a track-soil system under moving random loads

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Acta Mechanica Sinica 2019年第3期35卷 674-690页

作者： y.zhao l.T.Si H.Ouyang State Key laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Center for Computational MechanicsDalian University of TechnologyDalian 116023Chin School of Engineering University of LiverpoolLiverpool L69 3GHUK

The pseudo-excitation method combined with the integral transform method (PEM-ITM) is presented to investigate the ground vibration of a coupled track-soil system induced by moving random loads. Commonly in the track model, the rail, sleepers, rail pads, and ballast are modelled as an infinite Euler beam, discretely distributed masses, discretely distributed vertical springs, and a viscoelastic layer, respectively. The soil is regarded as a homogenous isotropic half-space coupled with the track using the boundary condition at the surface of the ground. By introducing a pseudo-excitation, the random vibration analysis of the coupled system is converted into a harmonic analysis. The analytical form of evolutionary power spectral density responses of the simplified coupled track-soil system under a random moving load is derived in the frequency/wavenumber domain by PEM-ITM. In the numerical examples, the effects of different parameters, such as the moving speed, the soil properties, and the coherence of moving loads, on the ground response are investigated.

关键词： Track-soil system Moving random loads Evolutionary power spectrum Pseudo-excitation method Integral transform method Vibration transmission

Twinning behavior of hot extruded AZ31 hexagonal prisms during uniaxial compression

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Journal of Magnesium and Alloys 2019年第1期7卷 90-97页

作者： y.R.zhao l.l.Chang J.Guo y.P.Jin School of Materials Science and Engineering Shandong UniversityJinanShandong 250061China Key laboratory for liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

Hot-extruded magnesium alloy AZ31 bar was cut into hexagonal prisms and then compressed at room temperature with the loading direction parallel to the extrusion direction(ED)or perpendicular to *** effective stress and strain evolution at center and corner region of the hexagonal prisms was simulated by using DEFORM 3D,while microstructure evolution was characterized by electron backscatter diffraction(EBSD).Relationship between twinning behavior and stress-strain evolution during compression at room temperature was *** results indicated that the compressive stress and strain levels at central region of hexagonal prisms were lower than those at the corner *** examination revealed that{10-12}twins activate during the compression and the volume fraction of twins at corner parts were less than that at the central parts,which was attributed to twin thickening and coalescence ***,the EBSD map indicated that the arise of{10-11}contraction twins and{10-11}-{10-12}double twins in compressed samples,especially in the corner region with loading axis perpendicular to ED,which were considered to be related to the high stress level at corner *** dislocation slips led to low-angle boundaries in lA⊥ED and lA//ED.

关键词： Magnesium alloy Simulation Microstructure Twinning Coalescence

EVOlUTION OF SINGlE EllIPTIC VORTEX RINGS

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Acta Mechanica Sinica 1997年第1期13卷 17-25页

作者： zhao, y Shi, XG Department of Mechanics and Engineering Science Peking University The State Key Laboratory for Turbulence Research Beijing China

The evolution of single elliptic vortex rings for initial aspect ratio (AR) = 2,4,6 has been studied. The incompressible Navier-Stokes equations are solved by a dealiased pseudo-spectral method with 64(3) grid points in a periodic cube. We find that there are three kinds of vortex motion as AR increases and bifurcation occurs at certain AR. The processes of advection, interaction and decay of vortex ring are discussed. Numerical results coincide with experiments and other authors' numerical simulation.

关键词： elliptic vortex ring pseudo-spectral method bifurcation vortex reconnection

Role of triggering receptor expressed on myeloid cells 1/2 in secondary injury after cerebral hemorrhage

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World Journal of Clinical Cases 2025年第9期13卷 1-12页

作者： Fan yi Hao Wu Hai-Kang zhao Xi’an Medical University Xi’an 710021Shaanxi ProvinceChina Department of Neurosurgery The Second Affiliated Hospital of Xi’an Medical UniversityXi’an 710038Shaanxi ProvinceChina

Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional *** is often accompanied by decreased consciousness and limb *** seriously affects patients’ability to live *** rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term *** in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after *** basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory *** inflammatory diseases can be upregulated and downregulated through receptor *** the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are *** analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently.

关键词： Cerebral hemorrhage Secondary injury Triggering receptor expressed on myeloid cells 1/2 Neurosurgery Inflammatory response

Numerical study of the circular opening effect on mechanical behaviour of rock under confinement

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第6期11卷 1201-1210页

作者： y.l.Gui J.l.Shang J.J.Ma Z.y.zhao school of engineering newcastle universitynewcastle upon tynene17ruunited kingdom school of civil and environmental engineering nanyang technological university639798singapore school of civil engineering sun yat-sen universityguangzhou510275china

Opening holes in rock including their size and distribution can affect the performance of rock-related structures.A good understanding on this will contribute to,for example,rock cavern design,and construction,tunnelling,and mining *** improve the understanding,a comprehensive investigation of the opening hole effect on the rock mechanical behaviour under biaxial loading condition is carried out by virtue of a hybrid continuum-discrete element *** specimens with both single hole and multi-hole of various radii are investigated and compared with the cases subjected to uniaxial *** is demonstrated that the confining pressure can increase both the stiffness and strength due to delaying the crack initiation and *** increase due to the confining pressure is more evident for the compressive *** single hole specimens with 0.75 mm radius hole,the increase ratio of the compressive strength is a linear increasing function with width and the increase ratio ranges from 2.15 for the specimen with 3.5 mm width to 2.45 for 10 mm *** the single hole specimen with 10 mm width,the increase ratio starts at 2.13 for the specimen with 0.75 mm radius hole,ascending to the peak of 2.37 for the specimen with 1 mm radius hole,followed by a decline to 2.2 for the specimen with 1.25 mm radius ***,for the multi-hole specimens,the increase ratio varies from 1.66 to *** addition,to verify the influence of confining pressure magnitude on the performance of the rock specimens,totalling 10 confining pressure levels are applied and *** simulation results show that even though there are opening holes in the specimens,the simulated compressive strength generally follows the generalised Hoek-Brown model.

关键词： Rock with opening Simulation Biaxial loading Strength Stiffness

Equivariant PT-symmetric real Chern insulators

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Frontiers of physics 2020年第1期15卷 63-69,F0004页

作者： y.X.zhao National laboratory of solid state microstructures and department of physics nanjing universitynanjing 210093china Collaborative innovation center of advanced microstructures nanjing universitynanjing 210093china

It was understood that Chern insulators cannot be realized in the presence of PT *** this paper,we reveal a new class of PT-symmetric Chern insulators,which has internal degrees of freedom forming real representations of a symmetry group with a complex endomorphism *** a generalization to the conventional 2n-dimensional Chern insulators with integer n≥1,these PT-symmetric Chern insulators have the n-th complex Chern number as their topological invariant,and have a Z classification given by the equivariant orthogonal K ***,in a fairly different sense,there exist ubiquitously Chern insulators with *** generalizing the Thouless charge pump argument,we find that,for a PT-symmetric Chern insulator with Chern number *** are equally many v flavors of coexisting left-and right-handed chiral *** modes with opposite chirality are complex conjugates to each other as complex representations of the internal symmetry group,but are not *** the physical dimensionality d=2,the PT-symmetric Chern insulators may be realized in artificial systems including photonic crystals and periodic mechanical systems.

关键词： topological insulator Chern insulator

Constructing Donor–Acceptor‑linked COFs Electrolytes to Regulate Electron Density and Accelerate the li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro letters 2025年第1期17卷 456-471页

作者： Genfu zhao Hang Ma Conghui Zhang yongxin yang Shuyuan yu Haiye Zhu yongjiang Sun Hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China yunnan yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective li^(+)transportation and conduction in solid-state li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective li^(+)migration and inhibit li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in li metal symmetric cell and high-capacity retention in li/liFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances li^(+)***,we anticipate that this work creates insight into the strategy for accelerating li^(+)conduction in high-performance solid-state li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state li metal battery