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国际医学放射学杂志 2024年第3期 373-373页

作者： H.kim S.Y.Yoo j.H.kim m.j.kim S.Lee T.Y.jeon 吴玉平

摘要目的探讨应用术前影像学指标预测胆道闭锁（BA）病人Kasai术后2年自体肝生存率的可行性。方法回顾性分析2000—2020年接受Kasai手术的190例BA病人，

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mg-Al Alloys manufactured by Casting and Hot Working Process

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journal of materials Science & Technology 2008年第1期24卷 96-98页

作者： j.m.kim j.H.jun W.j.jung Department of Applied materials Eng. Hanbat National University Daejeon 305-719 Korea Light materials Team Korea Institute of Industrial Technology Incheon 406-800 Korea

mechanical properties of mg-Al based alloys at different fabrication state,namely as-cast,hot rolled,and annealed,were investigated to develop the alloys that are suitable for the casting/hot working ***- imental results indicated that the castability such as hot cracking resistance tends to improve with increasing the aluminum ***,the elongation at elevated temperatures was observed to decrease as the AI content increases,implying difficulties in hot forming.A small amount of Zr additions could significantly enhance the room temperature mechanical properties of hot-rolled mg-6%Al-1%Zn *** tendency of remarkable grain coarsening at high temperatures was effectively reduced by the Zr *** analyses suggested that very fine Al-3Zr precipitates formed in the Zr-added alloy are responsible for the obtained results.

关键词： magnesium Casting Forming Tensile properties

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

Hyperreflective photonic crystals created by shearing colloidal dispersions at ultrahigh volume fraction

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microsystems & Nanoengineering 2024年第1期10卷 161-173页

作者： minji kim jong Bin kim Shin-Hyun kim Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea

Colloidal crystallization serves as one of the most economic and scalable production methods for photonic ***,insufficient optical performance,nonuniformity and low reproducibility remain challenges for advanced high-value *** this study,we optimally formulate a photocurable dispersion of silica particles and apply shear flow to unify the orientation of the colloidal crystals,ensuring high optical performance and *** silica particles experience strong repulsion at ultrahigh volume fractions of 50%but demonstrate low mobility,leading to polycrystalline *** shear flow to the dispersions allows the silica particles to rearrange into larger crystalline domains with a unidirectional orientation along the *** shear-induced structural change produces absolute reflectivity at the stopband as high as 90%and a high transparency of 90%at off-resonant wavelengths with minimal diffusive ***,the strong interparticle repulsion ensures a uniform volume fraction of particles throughout the dispersion,reducing deviations in the optical *** intricately micropattern the photocurable dispersions using ***,the photonic films and patterns can be stacked to form multiple layers,displaying mixed structural colors and multiple reflectance peaks without sacrificing *** superior photonic materials hold promise for various optical applications,including optical components and anticounterfeiting patches.

关键词： properties. dispersion reflectivity

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

ATP-binding cassette transporters as possible targets for the intervention of neurodegenerative diseases

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Neural Regeneration Research 2024年第4期19卷 721-722页

作者： Hiu Chuen Lok Glenda m.Halliday Woojin Scott kim Brain and mind Centre&School of medical Sciences The University of SydneySydneyNSWAustralia

ATP-binding cassette(ABC)transporters are ubiquitous membrane-bound proteins that are responsible for the translocation of a broad spectrum of substrates across cellular membranes,including lipids,amino acids,nucleosides,sugars,and ***,ABC transporters are highly expressed in the *** their functions in the brain still need to be elucidated,several members are implicated in the pathogenesis of neurodegenerative diseases,including Alzheimer’s disease(AD),Parkinson’s disease(PD),and frontotemporal *** this perspective,we will review current knowledge of ABC transporters in the central nervous system in terms of physiological functions and pathology in ***,we will explore the possibilities of ABC transporters as potential targets in the development of therapeutics for neurodegenerative diseases.

关键词： sugar degenerative diseases

Optimization of a High Speed Spinning Disk Spindle System for minimum RRO , NRRO, and Lightweight by Using G.A.

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厦门大学学报（自然科学版） 2002年第S1期41卷 89-90页

作者： Y H Choi S T kim K C Yoon j m kim Y j Kang Dept. of mechanical Design and manufacturing Changwon National UniversityDept. of Mechanical Engineering Changwon National UniversityR&D Cente FAGHANWHA Bearing Corp.Dept. of Mechanical Design and ManufacturingChangwon National UniversityDept. of Mechanical Design and ManufacturingChangwon National University Kyungnam 641-773 KoreaKyungnam 64 1-773 KoreaKyungnam 641 -020 KoreaSenoir Research Engineer Kyungnam 641-773 KoreaGraduate Student Kyungnam 641-773 KoreaGraduate Student

Law level of RRO(Repeatable Run Out), NRRO(Non Repe at able Run Out), and lightweight construction are a major trend in the high-speed HDD(Hard Disk Drive) sytem to reduce track misregestration and to achieve high track density, which lead to succeed in the market. However, it is not easy to r educe RRO, NRRO, and the weight of the spinning disk spindle system efficiently because lightweight construction and or bearing stiffness changes often yields a decrease in the static and dynamic stiffness of the system, and consequently hi gh vibrations may be generated as a results. Therefore, it is of importance to e valuate in advance the accurate dynamic behavior of the high speed spinning disk spindle system of a HDD sysem. This study introduces an optimum design of the high speed spinning disk spindle system of a HDD for minimum RRO, NRRO, and lightweight construction using a gene tic algorithm. The spinning disk, hub, and bearing components of a HDD system ar e modelled as appropriate finite elements respectively and their equations of mo tion are derived to construct the system equations of the whole spinning disk sp indle system of the HDD system. The RRO and NRRO responses of the spinning disk, due to exciting forces arised from ball bearing faults and rotating unbalance, are analyzed. In the design optimation, the hub thickness, the disk thickness, bearing positio ns (or bearing span) and bearing stiffness were set as design variables. The uni que objective function is obtained by multiplying an appropriate weighting facto r by multi-objective functions, such as RRO, NRRO, and the total weight of HDD the system. The constraints are maximum RRO limit, maximum weight linit, and the critical speed limit of the HDD spindle system. Results show that the RRO, NRRO, and weight are reduced by 6%, 66.7% and 28% r espectively compared with the initial design of the HDD system. Therefore, thi s present study can be used for an optimum design of the spinning disk spindle s yst

关键词： design optimization genetic algorithm multiobje ctive optimization repeatable run out non repeatable run out

Postmortem ^(7)Li NmR analysis for assessing the reversibility of lithium metal electrodes in lithium metal batteries

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journal of Energy Chemistry 2024年第7期94卷 430-440页

作者： jaewon Baek Sunha kim Hee-Tak kim Oc Hee Han Department of Chemical&Biomolecular Engineering KAISTDaejeon 34141Republic of Korea metropolitan Seoul Center Korea Basic Science InstituteSeoul 03759Republic of Korea Graduate School of Analytical Science&Technology Chungnam National UniversityDaejeon 34134Republic of Korea

Despite the proficiency of lithium(Li)-7 NmR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its *** this study,we conducted a comprehensive postmortem analysis utilizing ^(7)Li NmR,employing a stan-dard magic angle spinning probe to examine protective-layer coated Li metal electrodes and LiAg alloy electrodes against bare Li metal electrodes within Li metal batteries(LmBs).Our investigation explores the effects of sample burrs,alignment with the magnetic field,the existence of liquid electrolytes,and precycling on the ^(7)Li NmR *** contrasting NmR spectra before and after cycling,we identi-fied alterations in Li^(0) and Li^(+) signals attributable to the degradation of the Li metal *** NmR analyses decisively demonstrate the efficacy of the protective layer in mitigating dendrite and solid elec-trolyte interphase ***,we noted that Li*ions near the Li metal surface exhibit magnetic susceptibility anisotropy,revealing a novel approach to studying diamagnetic species on Li metal elec-trodes in *** study provides valuable insights and practical guidelines for characterizing distinct lithium states within LmBs.

关键词： NmR spectroscopy Lithium-7 Lithium metal battery Electrolyte Electrode-protective layer Solid electrolyte interface magnetic susceptibility anisotropy Lithium-metal NmR signal Diamagnetic^(7)Li NmR signal

Two intestinal microbiota-derived metabolites, deoxycholic acid and butyrate, synergize to enhance host defense peptide synthesis and alleviate necrotic enteritis

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journal of Animal Science and Biotechnology 2024年第3期15卷 1158-1172页

作者： Dohyung m.kim jing Liu melanie A.Whitmore Isabel Tobin Zijun Zhao Guolong Zhang Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA

Background Necrotic enteritis(NE)is a major enteric disease in poultry,yet effective mitigation strategies remain *** acid(DCA)and butyrate,two major metabolites derived from the intestinal microbiota,have independently been shown to induce host defense peptide(HDP)***,the potential synergy between these two compounds remains *** To investigate the possible synergistic effect between DCA and butyrate in regulating HDP synthesis and barrier function,we treated chicken HD11 macrophage cells and jejunal explants with DCA and sodium butyrate(NaB),either individually or in combination,for 24 ***,we performed RNA isolation and reverse transcrip-tion-quantitative PCR to analyze HDP genes as well as the major genes associated with barrier *** further determine the synergy between DCA and NaB in enhancing NE resistance,we conducted two independent trials with Cobb broiler *** each trial,the diet was supplemented with DCA or NaB on the day-of-hatch,followed by NE induction through sequential challenges with Eimeria maxima and Clostridium perfringens on d 10 and 14,*** recorded animal mortality after infection and assessed intestinal lesions on d *** impact of DCA and NaB on the microbiota in the ileum and cecum was evaluated through bacterial 16S rRNA gene *** We found that the combination of DCA and NaB synergistically induced multiple HDP genes in both chicken HD11 cells and jejunal ***,the gene for claudin-1,a major tight junction protein,also exhibited synergistic induction in response to DCA and ***,dietary supplementation with a combination of 0.75 g/kg DCA and 1 g/kg NaB led to a significant improvement in animal survival and a reduction in intestinal lesions compared to either compound alone in a chicken model of ***,the cecal microbiota of NE-infected chickens showed a marked decrease in SCFA-producing bacteria such as Bacteroides,F

关键词： Bile acids Host defense peptides metabolites microbiome Necrotic enteritis Short-chain fatty acids

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