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Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

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Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： Danko jeremic lydia jiménez-Díaz juan D.Navarro-lópez NeuroPhysiology&Behavior lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(AD)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in AD,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

FINITE ElEMENT NUMERICAl SIMUlATION OF TEMPERATURE FIElD IN METAl PATTERN CASTING SYSTEM AND "REVERSE METHOD" OF DEFINING THE THERMAl PHYSICAl COEFFICIENT

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Acta Metallurgica Sinica(English letters) 2007年第3期20卷 217-224页

作者： l. Chen P.l. Wang P.N. song j.Y. Zhang Mechanical Engineering College Tianjin University of Technology Tianjin 300191China

With the technology support of virtual reality and ANSYS software, an example on the simulation of temperature distribution of casting system during the solidification process was provided, which took the latent heat of phase change, the conditions for convection, and the interface heat transfer coefficient into consideration. The result of ANSYS was found to agree well with the test data. This research offers an unorthodox way or ＂reverse method＂ of defining the relevant thermal physical coefficient.

关键词： solidification process reverse method ANSYS software

Role of grain boundary character on Bi segregation-induced embrittlement in ultrahigh-purity copper

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journal of Materials Science & Technology 2023年第28期159卷 52-61页

作者： Y.X.Hua K.X.song H.T.liu j.W.Wang C.M.Zhang Y.j.Zhou B.Pang j.T.song j.l.He H.l.Zhao School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Henan Academy of Sciences Zhengzhou 450000China Henan Key laboratory of Advanced Conductor Materials Zhengzhou 450046China Provincial and Ministerial Co-construction of Collaborative Innovation Center of Nonferrous New Materials and Advanced Processing Technology Luoyang 471023China Center of Electron Microscopy and State Key laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China College of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Bismuth(Bi),as an impurity element in copper and copper-based alloys,usually has a strong tendency of grain boundary(GB)segregation,which depends on the GB ***,the influence of such a segregation on the properties of ultrahigh-purity copper has been rarely reported and the exact structural arrangements of Bi atoms at different GBs remain largely *** this study,we investigated the influ-ence of trace amounts of Bi(50-300 wt ppm)on the ductility of an ultrahigh-purity copper(99.99999%)in the range of room temperature to 900°*** tensile results show that the addition of Bi seriously damages the ductility of the ultrahigh-purity copper at temperatures of 450-900°C,which is due to the GB segregation of *** this basis,such a segregation behavior at different types of GBs,including high and low angle GBs(HAGBs/lAGBs),and twin boundaries(TBs),via the scanning electron microscope-electron backscattered diffraction(SEM-EBSD)and aberration-corrected scanning transmission electron microscope(AC-STEM)investigations,combined with the first-principles calculations were systematically *** atomistic characterizations demonstrate an anisotropic Bi segregation,where severe enrich-ment of Bi atoms typically occurs at the HAGBs,while the absence of Bi adsorption prevails at lAGBs or *** particular,the segregated Bi at random HAGBs exhibited the directional bilayer adsorption,while the special symmetrical7 HAGB presented a unique Bi-rich cluster *** findings pro-vide a comprehensive experimental and computational understanding on the atomic-scale segregation of impurities in metallic materials.

关键词： Grain boundary character Embrittlement Bi segregation Atomic configuration Ultrahigh-purity copper

Improved spatial decay bounds in the plane Stokes flow

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Applied Mathematics and Mechanics(English Edition) 2009年第7期30卷 833-838页

作者： j.C.song Department of Applied Mathematics Hanyang University

This paper investigates spatial decay bounds and a decay rate for the time- dependent Stokes flow of a viscous fluid in a semi-infinite channel. We show how to obtain a near optimal decay rate that is independent of the Reynolds number. We also show that a modification to an analysis given in the literature and a better choice of arbitrary constants yield a decay rate 1.328, which is clearly an improvement compared to 0.91 obtained in the referenced work.

关键词： spatial decay bound differential inequality decay rate

Asymptotic and other estimates for semilinear parabolic problem in semi-infinite cylinder

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Applied Mathematics and Mechanics(English Edition) 2011年第10期32卷 1333-1338页

作者： j.C.song Department of Applied Mathematics Hanyang University Ansan Gyeonggido 426791 Korea

The spatial decay of solutions to initial-boundary value problems for a semilinear parabolic equation in a semi-infinite cylinder of variable cross-section subject to zero condition on the lateral boundaries is investigated. A second-order differential inequality that shows the spatial decay O（exp（-z2/（4（t ＋ t0）））） for an l2p cross-sectional measure of the solution is obtained. A first-order differential inequality leading to growth or decay is also derived. In the case of growth, an upper bound for blow-up in space is obtained, while in the case of decay an upper bound for the total energy in terms of data is obtained.

关键词： spatial decay bound differential inequality decay rate

Symmetry-Protected Scattering in Non-Hermitian linear Systems

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Chinese Physics letters 2021年第2期38卷 29-35页

作者： l.jin Z.song School of Physics Nankai UniversityTianjin 300071China

Symmetry plays fundamental role in physics and the nature of symmetry changes in non-Hermitian *** the symmetry-protected scattering in non-Hermitian linear systems is investigated by employing the discrete symmetries that classify the random *** even-parity symmetries impose strict constraints on the scattering coefficients:the time-reversal(C and K) symmetries protect the symmetric transmission or reflection;the pseudo-Hermiticity(Q symmetry) or the inversion(P) symmetry protects the symmetric transmission and *** the inversion-combined time-reversal symmetries,the symmetric features on the transmission and reflection *** odd-parity symmetries including the particle-hole symmetry,chiral symmetry,and sublattice symmetry cannot ensure the scattering to be *** guiding principles are valid for both Hermitian and non-Hermitian linear *** findings provide fundamental insights into symmetry and scattering ranging from condensed matter physics to quantum physics and optics.

关键词： symmetry symmetric parity

Phragmén-lindelf and continuous dependence type results in a Stokes flow

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Applied Mathematics and Mechanics(English Edition) 2010年第7期31卷 875-882页

作者： j.C.song Department of Applied Mathematics Hanyang University

This paper investigates the asymptotic behavior of end effects for a Stokes flow defined on a three-dimensional semi-infinite cylinder. With homogeneous Dirichlet conditions of the velocity on the lateral surface of the cylinder, solutions either grow or decay exponentially in the distance from the finite end of the cylinder. In the case of decay, the effect of perturbing the equation parameters is also investigated.

关键词： Phragmen-lindelof continuous dependence decay bounds Stokes flow

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电解水制氢技术:进展、挑战与未来展望

工程科学学报 2025年第2期47卷 282-295页

作者：张正宋凌珺北京航空航天大学交通科学与工程学院北京102200

实现全球碳中和是各国在2050年制定的重要目标之一,旨在减缓气候变化的不良影响.氢能作为一种极具潜力的清洁能源,凭借其高能量密度、零碳排放、可再生性强等特性,被视为实现能源转型与应对气候变化的重要载体.为了实现这些目标,利用电... 详细信息

实现全球碳中和是各国在2050年制定的重要目标之一,旨在减缓气候变化的不良影响.氢能作为一种极具潜力的清洁能源,凭借其高能量密度、零碳排放、可再生性强等特性,被视为实现能源转型与应对气候变化的重要载体.为了实现这些目标,利用电解水制取氢气已经成为解决全球碳中和问题的重要关键方案之一.本文综述了碱性电解水、质子交换膜电解水、阴离子交换膜电解水和固体氧化物电解水制氢技术的最新进展,并对这四种电解水技术的工作原理、结构特点以及优缺点进行了详尽比较.此外,总结了电解水制氢催化剂材料的研究进展,尤其是新型材料的开发与结构优化,旨在提升材料的催化活性与稳定性.讨论了海水电解制氢和耦合制氢等新兴技术,强调通过电解质组成优化、高效双功能催化剂开发及利用小分子氧化反应热力学优势,可有效提升电解水制氢效率和系统稳定性.最后,提出了电解水制氢技术的发展趋势与未来研究方向,包括提升催化剂性能、降低电解过程能耗、开发新型电解设备等,旨在促进电解水制氢技术的进步,助力全球碳中和目标的实现,并为未来的研究提供参考与指导.

关键词：碳中和氢能电解水制氢催化剂电极材料

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A theoretical study on chemical ordering of 38-atom trimetallic Pd-Ag-Pt nanoalloys

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Chinese Physics B 2020年第7期29卷 548-554页

作者： songül Taran Ali Kemal Garip Haydar Arslan Department of Physics Duzce UniversityDuzce 81620Turkey Department of Physics Zonguldak Bulent Ecevit UniversityZonguldak 67100Turkey

In this study,truncated octahedron(TO)structure is selected for further analysis and we focus on 38-atom Pd-Pt-Ag trimetallic *** best chemical ordering structures of PdnAg32-nPt6 trimetallic nanoalloys are obtained at Gupta *** structures with the lowest energy at Gupta level are then re-optimized by density functional theory(DFT)relaxations and DFT results confirm the Gupta level calculations with small shifts on bond lengths indicating TO structure is favorable for 38-atom of PdnAg32-nPt6 trimetallic *** DFT excess energy analysis shows that Pd8Ag24Pt6 composition has the lowest excess energy value in common with excess energy analysis at Gupta *** Pd8Ag24Pt6 composition,eight Pd atoms are central sites of 8(111)hexagonal facets of TO,24 Ag atoms locate on surface,and 6 Pt atoms locate at the core of the *** is also obtained that all of the compositions except Pd18Ag14Pt6 and Pd20Ag12Pt6 exhibit a octahedral Pt ***,it is observed that there is a clear tendency for Ag atoms to segregate to the surface and also Pt atoms prefer to locate at core due to order parameter(R)variations.

关键词： nanoalloys chemical ordering optimization density functional theory(DFT)