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A Quantitative Analysis of mn Segregation at Partitioned Ferrite/Austenite Interface in a Fe-c-mn-Si Alloy

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Journal of materials Science & Technology 2009年第3期25卷 383-388页

作者： H. Guo S.W. Yang c.J.Shang x.m. Wang x.L. He Department of materials Physics and chemistry University of Science and Technology Beijing Beijing 100083 China

mn segregation at austenite/ferrite interface is studied in a Fe-c-mn-Si alloy held at 656℃. mn is partitioned during the growth of ferrite and as a result, a mn pile-up exists in front of interface on the matrix side. An approach to evaluate mn segregation quantitatively is developed by combining STEm raster window scanning and simulation of the interaction of the electron beam with the sample to subtract the contribution of mn pile-up and obtain pure mn segregation value. The evaluated maximum mn interfacial segregation is in the order of a half-monolayer.

关键词： Interfacial segregation Phase transformation STEm Beam broadening

Hard yet tough and self-lubricating(cuNiTiNbcr)c_(x) high-entropy nanocomposite films:Effects of carbon content on structure and properties

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Journal of materials Science & Technology 2024年第6期173卷 20-30页

作者： Y.T.Li x.m.chen x.K.Zeng m.Liu x.Jiang Y.x.Leng Key Laboratory of Advanced Technologies of materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China School of mechanical and Electrical Engineering Mianyang Teachers’CollegeMianyang 621000China

The single-phase high-entropy alloy film is difficult to meet severe friction conditions due to its low hardness and high friction ***-composite structure film is composed of at least two separated phases,showing the properties of strength and toughness integration and excellent wear *** design of nanocomposite structures can effectively improve the mechanical properties and tribological properties of high-entropy alloy *** this study,the(cuNiTiNbcr)c_(x) nanocomposite high-entropy films(HEFs)integrated with high hardness,high toughness,and self-lubrication were synthesized by the double-target co-sputtering *** effect of carbon content on microstructure,mechanical properties,and tribological properties of(cuNiTiNbcr)c_(x) films was *** the increase of carbon content in the HEFs,the carbon atoms preferentially react with Ti,Nb,and cr to form a(TiNbcr)c ceramic-reinforced phase,and then the excess carbon atoms precipitate in the form of amorphous carbon(a-c)lubricating phase in the *** structure of the HEFs changes from an amorphous structure to a nanocomposite structure of amorphous(amorphous cuNiTiNbcr phase+a-c phase)/nanocrystalline(TiN-bcr)c *** the carbon content is about 21.2 at.%,the carbide phase in the film reaches saturation and the hardness and modulus of the films are highest,which are 18 GPa and 228 GPa,*** HEFs with a carbon content of 44.0 at.%show the best toughness and tribological properties with a friction coefficient of 0.16 and a wear rate of 2.4×10^(-6) mm^(3)/(N m),which is mainly attributed to the excellent resistance to fatigue crack growth and the interfacial lubricating layer formed in the friction *** nanocomposite(cuNiTiNbcr)c_(x) HEFs show very promising application prospect in the field of friction protection.

关键词： High-entropy films Nanocomposite Double-target co-sputtering Strengthening-toughening Tribological properties

c2-cofiniteness of cyclic-Orbifold Vertex Operator Superalgebras

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Algebra colloquium 2017年第2期24卷 315-322页

作者： chunrui ai School of mathematics and Statistics Zhengzhou University Zhengzhou 450001 China

In this paper, it is proved that for any c2-cofinite, simple, cFT-type vertex operator superalgebra V and a finite solvable group G consisting of automorphisms of V, the fixed point subalgebra Vc is a c2-cofinite vert... 详细信息

关键词： vertex operator superalgebra c2-cofiniteness solvable group

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EmBASE,Ovid mEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Discovery of new mAx-phase-like layered ternary carbide V_(8)P_(6)c:crystal structure,thermal expansion,and elastic properties

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Journal of materials Science & Technology 2024年第7期174卷 55-62页

作者： H.x.chen L.Sheng Z.L.Zhang x.c.Wen D.L.Yang x.Y.Ye P.Q.Dai School of materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial Key Laboratory of Advanced materials Processing and Application Fuzhou 350118China State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the laminated structure,mAx phases and mAx-phase-like compounds possess outstanding dam-age tolerance capability with good thermal/electrical conductivity and other charming functional prop-erties,showing a bright future for structural-functional ***,a new mAx-phase-like ternary car-bide V_(8)P_(6)c with layered characteristics was *** to the alternate stacking of hexagonal-arranged m/A/x atom layers in mAx phases,V_(8)P_(6)c has a layered structure formed by a repeated stacking of the slabs consisting of V_(6)c-octahedrons and VP 6-distorted-octahedrons in three-atomic layers *** thermal expansion anisotropy was revealed,with the thermal expansion coefficients(TEcs)along a-axis,c-axis,and the average value,equal toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(L)=9.14(5)μK^(−1),*** dilation along the c-axis was mainly dominated by out-plane V-P bonds be-tween layered *** to the pressure-dependent lattice parameters,the polycrystalline bulk modulus(B_(0)=185(9)GPa)and high compressibility anisotropy factor(B_(a)/B_(c)=1.64)was ***-while,the second-order elastic constants were calculated,and the elastic moduli,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between layer slabs by out-plane V1-P bond was revealed by the bond stiffness model,with a bond stiffness close to the m-A bond in mAx ***,good damage tolerance capability was predicted according to Paugh’s ratio(G/B=0.616)and cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical mAx *** discovery of V_(8)P_(6)c provides a new member of mAx-phase-like damage-tolerant ceramic with relatively low density,moderate thermal expansion,and anisotropic compressibility,and the unique lay-ered structure is inspiring for exploring new layered ternary ceramics.

关键词： New ternary carbide mAx phase Thermal expansion Elastic constants Anisotropy

Effect of multi-walled carbon nanotube addition on the microstructures and mechanical properties of Ti(c,N)-based cermets

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Journal of Advanced ceramics 2018年第1期7卷 58-63页

作者： P.WU S.c.LIU x.R.JIANG college of chemistry and materials Science Longyan University

The surface modification of multi-walled carbon nanotubes(mWcNTs) was carried out using plasma treatment. The microstructures of the prepared cermets with different additions of mWcNTs were investigated by scanning electron microscopy(SEm), transmission electron microscopy(TEm), energy dispersive x-ray analysis(EDx), and x-ray diffraction(xRD). mechanical properties such as transverse rupture strength(TRS), fracture toughness(K_(Ic)), and hardness(HRA) were measured. The results showed that some reactive groups were successfully modified on the surface of mWcNTs, resulting in the improvement of dispersibility. most of the amorphous carbons and impurities were peeled from the mWcNTs. Increasing mWcNT addition decreased the dissolution of tungsten, titanium, and molybdenum in the binder phase. The cermet with 0.5 wt% mWcNT addition showed the highest TRS and fracture toughness. The strengthening mechanisms were attributed to the finer grain size, the homogeneous microstructure, and the higher volume fraction of binder phase in the binder. The toughening mechanisms were characterized by bridging and pulling-out.

关键词： Ti(c,N)-based cermets microstructure mechanical property fracture toughness

multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.Smith Jessica L.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

multiple sclerosis(mS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). Patients with mS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

mIcROSTRUcTURE EVOLUTION AND mEcHANIcAL HARDENING OF HYPEREUTEcTOID PEARLITIc STEEL DURING cOLD ROLLING

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Acta metallurgica Sinica(English Letters) 2007年第4期20卷 287-292页

作者： x. Zhang c.x. Wang x.m. Liu Q.N. Shi Key Laboratory of Advanced materials of Yunnan Province Kunming University of Science and Technology Kunming 650093 China Institute for Structural materials Central Iron and Steel Research InstituteBeijing 100081 China

The microstructure evolution of different cold rolling reductions （from 0 to 81.6%） was studied by SEm （scanning electron microscopy） and TEm （transmission electron microscope）. The study showed that the orientation multiplicity of pearlitic lamellas resulted in inhomogeneous deformation of different pearlitic lamellas, and with the increase of reduction, the microstructure underwent a course of ＂homogeneity → inhomogeneity → homogeneity＂. The result of xRD （x-ray diffraction） analysis indicated that cementite did not decompose and dissolve into ferrite; the results of the mechanical property test suggested that the relationship between Rp0.2 （yield strength） and ε （true strain） was in good agreement with Hollomon relationship. With the equation Rp0.2 = 1465ε^0.18, the yield strength of the steel in different reductions could be well predicted.

关键词： cold rolling hypereutectoid pearlitic steel microstructure evolution mechanical hardening