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Superplasticity of fine-grained mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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journal of magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.jeong S.w.Lee w.j.Kim Department of materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

Orchard Sports Injury and Illness Classification System (OSIICS) Version 15

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journal of Sport and Health Science 2024年第4期13卷 599-604页

作者： john w.Orchard Ebonie Rio Kay m.Crossley jessica j.Orchard margo mountjoy School of Public Health University of SydneySydneyNSW 2006Australia La Trobe Sport and Exercise medicine Research Centre La Trobe UniversityMelbourneVIC 3083Australia Department of Family medicine McMaster UniversityHamilton L8S 4L8Canada

Background:Sports medicine(injury and illnesses)requires distinct coding systems because the International Classification of Diseases is insuf-ficient for sports medicine *** Orchard Sports Injury and Illness Classification System(OSIICS)is one of two sports medicine coding systems recommended by the International Olympic *** updates of coding systems are ***:For Version 15,updates for mental health conditions in athletes,sports cardiology,concussion sub-types,infectious diseases,and skin and eye conditions were considered particularly ***:Recommended codes were added from a recent International Olympic Committee consensus statement on mental health conditions in *** landmark sports cardiology papers were used to update a more comprehensive list of sports cardiology *** union protocols on head injury assessment were used to create additional concussion ***:It is planned that OSIICS Version 15 will be translated into multiple new languages in a timely fashion to facilitate international *** large number of recently published sport-specific and discipline-specific consensus statements on athlete surveillance warrant regular updating of OSIICS.

关键词： Sports cardiology Dermatology Eye injuries Concussion Infectious diseases Sports injury classification

Compressive property and energy absorption characteristic of interconnected porous mg-Zn-Y alloys with adjusting Y addition

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journal of magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu S.j.Liu B.wang w.B.Sun X.j.Liu Z.w.Han College of materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different mg-Zn-Y ternary phases appear:I-phase(mg_(3)Zn_(6)Y),w-phase(mg_(3)Zn_(3)Y_(2)),and LPSO phase(mg_(12)ZnY).when the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30mPa to 9.23 mPa,and the energy absorption capacity increases from 7.33 mj/m^(3)to 10.97 mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements microstructure Compressive behavior Energy absorption characteristic

The CCD instrument background of the SmILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： m.w.j.Hubbard O.Hetherington D.j.Hall T.w.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The ESA and CAS SmILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making approach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.P.SALAImANImAGUDAm j.jAYAPRAKASH Department of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have provided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a complex *** paper presents alternatives and criteria for selection of digital fabrication techniques by adopting the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)printing,shotcrete,smart dynamic casting,material intrusion,mesh molding,injection concrete 3D printing,and thin forming *** criteria include formwork utilization,reinforcement incorporation,geometrical complexity,material enhancement,assembly complexity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorporation,build area,and geometrical complexity play a pivotal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D printing emerged as the best performer,however the shotcrete and mesh molding techniques in the second and third positions.

关键词： digital fabrication multicriteria decision-making concrete 3D printing

Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEmATI m.SEFID A.KARImIPOUR A.j.CHAmKHA Faculty of mechanical Engineering Yazd UniversityYazd ***Iran Department of mechanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(mF)is very vital due to its existence in various sectors of industry and *** present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection *** temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is *** formulation of the problem is derived with the lattice Boltzmann method(LBm)by code writing via the FORTRAN *** variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed mF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are *** findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates *** is the lowest cooling performance index and mF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research.

关键词： thermal performance analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity

Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECH 2024年第2期5卷 239-246页

作者： j.m.Lukasiewicz C.C.m.van de wiel L.A.P.Lotz m.j.m.Smulders wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

Surgeon preferences in the treatment of thumb carpometacarpal osteoarthritis

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world journal of Orthopedics 2024年第5期15卷 435-443页

作者： Edward j wu Bradley w Fossum wyatt Vander Voort Christopher O Bayne Robert m Szabo Department of Orthopedic Surgery University of Minnesota Medical SchoolMinneapolisMN 55455United States Department of Orthopaedic Surgery UC Davis School of MedicineSacramentoCA 95817United States

BACKGROUND Primary thumb carpometacarpal(CmC)osteoarthritis is one of the most common conditions encountered by hand *** the vast number of operations that have been proposed,none have demonstrated results significantly superior to trapeziectomy *** The purpose of our study was to determine why surgeons opt for their technique in treating CmC *** A cross-sectional survey of active members of the American Society for Surgery of the Hand was conducted to evaluate the reasons behind their preferred technique in the treatment of isolated thumb CmC *** were contacted by email once and provided with a link to a de-identified survey consisting of 5 treatment questions and 5 demographic *** Of 950 responses were received.40.5%of surgeons preferred trapeziectomy+ligament reconstruction tendon interposition(LRTI),followed by trapeziectomy+suspensionplasty(28.2%),suture button suspension(5.9%),trapeziectomy alone(4.6%),prosthetic arthroplasty(3.2%),arthrodesis(1.1%),and other(6.6%).Proponents of trapeziectomy+LRTI cited familiarity(73.2%),exposure during fellowship(48.8%)and less proximal migration(60%)to be the main reasons affecting their *** who preferred trapeziectomy+suspensionplasty most reported simplicity(74.9%),fewer complications(45.3%),less proximal migration(43.8%),and avoidance of autogenous tissue harvest(42.7%).Advocates of suture button suspension cited avoidance of autogenous tissue harvest(80.4%),shorter immobilization(76.8%),and quicker recovery(73.2%)with their *** of trapeziectomy alone cited simplicity(97.7%),fewer complications(86.4%),and avoidance of autogenous tissue harvest(59.1%).In their comments,45%of surgeons choosing trapeziectomy alone cited evidence as an additional *** of prosthetic arthroplasty cited improved pinch strength(83.3%)and improved range of motion(63.3%),while those preferring arthrodesis cited better pinch strength(90%)and freque

关键词： Thumb carpometacarpal Osteoarthritis Trapeziectomy Ligament reconstruction tendon interposition Suspensionplasty Preferences Trends