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colorful Insights： Advances in Imaging Drive Nove 3reakthroughs in ca^2＋ Signaling

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Molecular Plant 2015年第3期8卷 352-355页

作者： alex costa jorg Kudla Dipartimento di Bioacienze Università degli Studi di Milano Via G. Celoria 26 20133 Milan Italy Istituto di Biofisica Consiglio Nazionale delle Ricerche Via G. Celoria 26 20133 Milan Italy Institut für Biologie und Biotechnologie der Pflanzen Universitat Münster Schlossplatz 4 48149 Münster Germany

In plants, ca^2＋ signals occur in response to both environmental and developmental stimuli. These signals involve increases in [ca^2＋] in compartments such as the cytoplasm, nucleus, and mitochondria, and can display multiple shapes ranging from sin- gle transients to repetitive ca^2＋ oscillations. Generation and shaping of stimulus specific [ca^2＋] signatures depends on ca^2＋ influxes and effluxes occurring at both the plasma membrane （PM） and membranes of the different subcellular compartments.

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Vibration control of fluid-conveying pipes: a state-of-the-art review

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1423-1456页

作者： Hu DING j.c.jI Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312074Zhejiang ProvinceChina Shanghai Institute of Aircraft Mechanics and control Shanghai 200092China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

Fluid-conveying pipes are widely used to transfer bulk fluids from one point to another in many engineering *** are subject to various excitations from the conveying fluids,the supporting structures,and the working environment,and thus are prone to vibrations such as flow-induced vibrations and acoustic-induced *** can generate variable dynamic stress and large deformation on fluid-conveying pipes,leading to vibration-induced fatigue and damage on the pipes,or even leading to failure of the entire piping system and catastrophic ***,the vibration control of fluid-conveying pipes is essential to ensure the integrity and safety of pipeline systems,and has attracted considerable attention from both researchers and *** present paper aims to provide an extensive review of the state-of-the-art research on the vibration control of fluid-conveying *** vibration analysis of fluid-conveying pipes is briefly discussed to show some key issues involved in the vibration ***,the research progress on the vibration control of fluid-conveying pipes is reviewed from four aspects in terms of passive control,active vibration control,semi-active vibration control,and structural optimization design for vibration ***,the main results of existing research on the vibration control of fluid-conveying pipes are summarized,and future promising research directions are recommended to address the current research *** paper contributes to the understanding of vibration control of fluid-conveying pipes,and will help the research work on the vibration control of fluidconveying pipes attract more attention.

关键词： fuid-conveying pipe vibration passive control nonlinear energy sink(NES) active control semi-active control

Dynamic Mechanical Relaxation in Bulk Metallic Glasses:A Review

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journal of Materials Science & Technology 2014年第6期30卷 523-545页

作者： j.c.Qiao j.M.Pelletier Université de Lyon CNRS France INSA-Lyon MATEIS UMR5510 F-69621 Villeurbanne France

Metallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the mechanical, thermal properties and application of the metallic glasses. In addition, we focus on the dynamic mechanical relaxation behaviors, i.e. main （α） and secondary （β） relaxations, in metallic glasses. The mechanical relaxation behaviors are connected to the mechanical properties and physical properties in glassy materials. The main relaxation in glassy materials is related to the glass transition phenomenon and viscous flow. On the other hand, the β relaxation is linked to many fundamental issues in metallic glasses. In these materials relaxation processes are directly related to the plastic deformation mechanism. The mechanical relaxations, particularly, the β relaxation provides an excellent opportunity to design metallic glasses with desired physical and mechanical properties. We demonstrate the universal characteristics of main relaxation in metallic glasses. The phenomenological models and the physical theories are introduced to describe the main relaxation in metallic glasses. In parallel, we show the dependence of the α. and β relaxations on the thermal treatments in metallic glasses. Finally, we analyze the correlation between the atomic mobility and the thermo-mechanical treatments in metallic glasses. On the one hand, the atomic mobility in metallic glasses is reduced by physical aging or crystallization. On the other hand, the atomic mobility in metallic glass is enhanced by deformation （i.e. compression and cold rolling）. Importantly, to analyze the atomic mobility in amorphous materials, a physical theory is introduced. This model invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy materials.

关键词： Metallic glasses Mechanical properties Main relaxation Secondary relaxation Physical analysis

The Kirkendall effect on erosion resistance of chrome-coated 25cr3Mo2WNiV and 30SiMn2MoV gun barrel steels

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journal of Materials Science & Technology 2024年第10期177卷 246-255页

作者： c.H.Dou P.F.jin c.Z.Wang j.j.Li c.Zhang j.F.Huang c.Zhang Key Laboratory for Advanced Materials Processing State State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China National joint Engineering Research center for Abrasion control and Molding of Metal Materials School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471003China

This study aimed to investigate the erosion behavior and mechanism of a newly developed 25cr3Mo2WNiV steel with a chrome coating using promoted ignition combustion *** erosion threshold pressure and temperature of the chrome-coated 25cr3Mo2WNiV steel were determined to be 0.2 MPa and 254.3 K higher than those of traditional chrome-coated 30SiMn2MoV ***,Kirkendall voids and inter-diffusion between the cr coating and matrix were first observed before *** improved erosion resistance of the chrome-coated 25cr3Mo2WNiV steel was attributed to the suppression of the Kirkendall effect,which minimized heat generation at the cr/matrix interface by pre-venting oxygen diffusion and reducing oxygen affinity.

关键词： Erosion resistance Kirkendall effect cr coating Gun steel

cONTINUUM VOID NUcLEATION MODEL FOR Al-Mg ALLOY SHEET BASED ON MEASURED PARTIcLE DISTRIBUTION

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Acta Mechanica Solida Sinica 2009年第5期22卷 391-398页

作者： c.j.Butcher Department of Mechanical Engineering University of New BrunswickFrederictonNBCanadaE 3B 5A3

Void nucleation within measured particle fields of an aluminum alloy is investigated to develop a continuum nucleation model which reflects nucleation at the individual particle scale. A nucleation model for heterogeneous particle distributions is synchronized with the continuum model of chu and Needleman using the average nucleation strain. The parameters in the continuum model are identified from the particle fields and are evaluated over the range of stress states observed in sheet metal forming. The synchronized continuum nucleation model achieves very good agreement with the nucleation trends for three measured particle fields in uniaxial tension, plane strain, and equal-biaxial tension.

关键词： void nucleation ductile fracture second-phase particles aluminum

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

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

Synthesis and characterization of Nanocapsules of α-Fe(NicoAl) Solid-solution

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journal of Materials Science & Technology 2005年第3期21卷 297-300页

作者： DianyuGENG j.c.Kim c.j.cho chonglincHEN XianguoZHAO ZidongZHANG ShenyangNationalLaboratoryforMaterialsScience InstituteofMetalResearchandInternationalCentretbrMaterialsPhysicsChineseAcademyofSciencesShenyang110016China KoreaInstituteofMachineryandMaterials 66Sangnam-dongChangwonKynugnam640-010SouthKorea

α-Fe(NicoAl) solid-solution nanocapsules were prepared with pure powders of Fe, Ni, co and Al by the plasma arc-discharging using a copper crucible. The shapes of the nanocapsules are in polyhedrons with the core/shell structure. The body centered cubic (Bcc) phase is formed in the core. The size of the nanocapsules is in the range of 10-120 nm and the thickness of the shell is 4-11 nm. Saturation magnetization jS=150 Am2/kg and coercivity iHc=24.3 kA/m are achieved for the nanocapsules.

关键词： Nanocapsules a-Fe solid solution Plasma arc discharge Magnetic properties