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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

Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： n.IQBAL j.CHoI S.F.SHAH C.lee S.lee Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline ni-rich LinixMnyCo_(z)o_(2)(x≥0.8)(nMC)particles with poly(3,4-ethylenedioxythiophene)(PEDoT).The simulation results show that the coating of primary nMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of nMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation ni-rich LinixMnyCo_(z)o_(2)(x>0.8)(nMC)

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.lee S.CHAnG j.lee Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).we also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

A hydrodynamic modelling of wave-activated bodies for wavelet marine regions

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Clean Energy 2024年第2期8卷 35-47页

作者： j.S.Peh Mohammed w.Muhieldeen n.H.Shuaib Mechanical Engineering Department Faculty of EngineeringTechnology&Built EnvironmentUCSI UniversityKuala Lumpur56000Malaysia MTC Engineer Sdn.Bhd Shah AlamSelangorMalaysia

Recently,most wave energy research has targeted sea areas with high power density under extreme wave conditions for *** trend often leads to higher energy costs for wave power ***,many marine areas with low power density,characterized by wavelet conditions and less destructive forces than extreme wave conditions,remain ***,this study aimed to propose a wave-activated body model for sea regions with wavelet *** wave-activated body design process encompassed site selection,parameter determination,geometry design,comparison and performance evaluation using the AnSYS®AQwA *** results indicated that the proposed device achieved the desired heave motion,with an amplitude range of 1.2 to-2.5 m,validating its potential for deployment in marine regions with wavelet ***,while the proposed design is optimized for wavelet conditions,it was found to have potential limitations in extreme wave *** observation emphasizes the challenge of formulating a generalized design suitable for both ***,it is pivotal for wave-activated body designs to be customized based on the specific ocean conditions they target,underscoring the need for specialized designs of wave energy converters that consider the unique wave characteristics of their deployment sites.

关键词： wave energy converter South China sea renewable and sustainable energy wavelet AnSYS AQwA hydrodynamic wave-activated bodies

Perturbations in the earthworm metabolite profile during a two-week exposure to metformin

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Emerging Contaminants 2024年第3期10卷 221-229页

作者： j.D.Gillis G.w.Price S.o.Prasher Department of Bioresource Engineering McGill UniversityFaculty of Agricultural and Environmental SciencesMacdonald-Stewart Building MS1-02721111 Lakeshore RoadSainte-Anne-de-BellevueQuebecH9X 3V9Canada Department of Engineering Dalhousie UniversityFaculty of Agriculture39 Cox RoadPO Box 550TruroNova ScotiaB2N 5E3Canada

Metformin is among the most prescribed pharmaceuticals in many countries,and as a result has shown up in biosolids derived from municipal wastewater treatment that are destined for land *** humans taking metformin,the effects include reduced glucose uptake in the intestine,a reduction in gluconeogenesis,increased oxidation of fatty acids,and reduced fatty acid *** effects of metformin on soil-dwelling organisms are not well *** study tested the effects of metformin exposure(0,10,40,160,640μg g^(-1))on the earthworm(***)at four time points(6 h,2 d,7 d,and 14 d)using GC-MS to reveal sub-lethal effects and elucidate potential modes of action for *** were no mortalities observed,and earthworms exposed to the highest concentrations(160 and 640μg g^(-1))gained weight relative to the control on days 7 and *** reductions on day 7 were observed for glucose and malic acid(consistent with a reduction in gluconeogenesis),and for palmitic and margaric acid(consistent with increased oxidation and reduced synthesis of fatty acids).Lactic acid ranked first and second among canonicals 1 and 2 respectively and led to significant differences in discriminant scores across concentration and *** levels increased to equal or greater than the control on day 14,likely caused by reduced exposure as metformin is reported to be readily transformed by microorganisms under aerobic *** observations were consistent with the known effects of metformin in humans,and suggests that a similar mode of action exists in earthworms.

关键词： Metabolites Toxicity Earthworms Metformin GC-MS

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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nano Materials Science 2024年第2期6卷 193-200页

作者： M.I.Ikim G.n.Gerasimov V.F.Gromov o.j.Ilegbusi L.I.Trakhtenberg n.n.Semenov Federal Research Center for Chemical Physics of RAS MoscowRussia University of Central Florida OrlandoFLUSA Moscow Institute of Physics and Technology(State University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow State University MoscowRussia

The hydrothermal synthesis of In_(2)o_(3)and Ceo_(2)–In_(2)o_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of In_(2)o_(3),intermediate products In(oH)_(3)and InooH are formed,which are the precursors of stable cubic(c-In_(2)o_(3))and metastable rhombohedral(rh-In_(2)o_(3))phases,respectively.A transition from c-In_(2)o_(3)to rh-In_(2)o_(3)is observed with the addition of Ceo_(2).The introduction of cerium into rh-In_(2)o_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)o_(3).The data on the sensor activity of the composites correlate with XPS results in which Ceo_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)o_(3).The reverse situation is observed in composites based on c-In_(2)o_(3).Compared to In_(2)o_(3)and Ceo_(2)–In_(2)o_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)o_(3)and Ceo_(2).

关键词： Cerium oxide Indium oxide nanocomposite Hydrothermal method Cubic phase Rhombohedral phase Sensor response Conductivity Hydrogen Response/recovery time

Telomeric DnA breaks in human induced pluripotent stem cells trigger ATR-mediated arrest and telomerase-independent telomere damage repair

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journal of Molecular Cell Biology 2024年第3期16卷 46-60页

作者： Katrina n.Estep john w.Tobias Rafael j.Fernandez Brinley M.Beveridge F.Brad johnson Department of Pathology and Laboratory Medicine University of PennsylvaniaPhiladelphiaPA 19104USA Quantiative Biosciences Merck&Co.Inc.West PointPA 19486USA Penn Genomic Analysis Core University of PennsylvaniaPhiladelphiaPA 19104USA

Although mechanisms of telomere protection are well-defined in differentiated cells,how stem cells sense and respond to telomere dysfunction,in particular telomeric double-strand breaks(DSBs),is poorly ***,we report the DnA damage signaling,cell cycle,and transcriptome changes in human induced pluripotent stem cells(iPSCs)in response to telomere-internal *** engineer human iPSCs with an inducible TRF1-FokI fusion protein to acutely induce DSBs at *** this model,we demonstrate that TRF1-FokI DSBs activate an ATR-dependent DnA damage response,which leads to p53-independent cell cycle arrest in *** CRISPR–Cas9 to cripple the catalytic domain of telomerase reverse transcriptase,we show that telomerase is largely dispensable for survival and lengthening of TRF1-FokI-cleaved telomeres,which instead are effectively repaired by robust homologous recombination(HR).In contrast to HR-based telomere maintenance in mouse embryonic stem cells,where HR causes ZSCAn4-dependent extension of telomeres beyond their initial lengths,HR-based repair of telomeric breaks is sufficient to maintain iPSC telomeres at a normal length,which is compatible with sustained survival of the cells over several days of TRF1-FokI *** findings suggest a previously unappreciated role for HR in telomere maintenance in telomerase-positive iPSCs and reveal distinct iPSC-specific responses to targeted telomeric DnA damage.

关键词： telomeres telomerase alternative lengthening of telomeres pluripotent stem cells DnA damage double-strand breaks

Mathematical beauty and Palladian architecture:Measuring and comparing visual complexity and diversity

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Frontiers of Architectural Research 2024年第4期13卷 729-740页

作者： ju Hyun lee Michael j.ostwald School of Built Environment Faculty of ArtsDesign&ArchitectureThe University of New South WalesSydneyNSW 2052Australia

Palladio’s design principles,including proportion and harmony,have often been associated with mathematical definitions of ***,the geometric and semantic properties of his fac¸ades have rarely been analysed in a holistic *** is little evidence of how mathematical beauty may be embodied in his *** research investigates complexity(fractal dimension or D)and diversity(perplexity or PP)as aesthetic indices,aiming to capture distinct characteristics of Palladian *** D and PP values of 22 Palladian villa fac¸ades are measured and analysed,before being compared with those of three Renaissance facades by Sebastiano *** combination of D and PP captures the geometric and semantic aesthetic qualities of architectural ***,the developed scatter plot of D and PP results supports the identification of four distinct aesthetic types of Palladian fac¸ade *** novel combination of D and PP measures contributes to a better understanding of one definition of the mathematical beauty of architecture,wherein“the w.ole is other than the sum of the parts”in compositional terms(a famous Gestalt principle).Specifically,this research provides new mathematical insights into the visual character of Palladian architecture and compares two important measures thereof.

关键词： Palladian architecture Complexity Diversity Mathematical beauty Perplexity Fac¸ade design

The impact of maternal immune activation on the morphology and electrophysiological properties of postnatally-born neurons in the offspring

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neural Regeneration Research 2024年第2期19卷 399-400页

作者： Emilio j.Galván Angelica Zepeda Departamento de Farmacobiología CINVESTAV Unidad Sur CdMxMéxico、Centro de Investigaciones sobre el EnvejecimientoCIE-CinvestavCdMxMéxico Departamento de Medicina Genómica y Toxicología Ambiental Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoUNAMCdMxMéxico

Pregnancy comes with a combination of physical changes and physiological immunosuppression that increases the susceptibility of women to pathogens and in turn,rises the prevalence of infectious diseases.

关键词： prevalence activation impact

Cavity-agnostic acoustofluidic manipulations enabled by guided flexural waves on a membrane acoustic waveguide actuator

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Microsystems & nanoengineering 2024年第2期10卷 153-171页

作者： Philippe Vachon Srinivas Merugu jaibir Sharma Amit Lal Eldwin j.ng Yul Koh joshua E.-Y.lee Chengkuo lee Department of Electrical and Computer Engineering National University of SingaporeSingaporeSingapore Institute of Microelectronics Agency for ScienceTechnology and Research(A*STAR)SingaporeSingapore SonicMEMS Laboratory School of Electrical and Computer EngineeringCornell UniversityIthacaNYUSA School of Electrical and Data Engineering University of Technology SydneyUltimoNSWAustralia

This article presents an in-depth exploration of the acoustofluidic capabilities of guided flexural waves(GFws)generated by a membrane acoustic waveguide actuator(MAwA).By harnessing the potential of GFws,cavity-agnostic advanced particle manipulation functions are achieved,unlocking new avenues for microfluidic systems and lab-on-a-chip *** localized acoustofluidic effects of GFws arising from the evanescent nature of the acoustic fields they induce inside a liquid medium are numerically investigated to highlight their unique and promising *** traditional acoustofluidic technologies,the GFws propagating on the MAwA’s membrane waveguide allow for cavity-agnostic particle manipulation,irrespective of the resonant properties of the fluidic ***,the acoustofluidic functions enabled by the device depend on the flexural mode populating the active region of the membrane *** demonstrations using two types of particles include in-sessile-droplet particle transport,mixing,and spatial separation based on particle diameter,along with streaming-induced counter-flow virtual channel generation in microfluidic PDMS *** experiments emphasize the versatility and potential applications of the MAwA as a microfluidic platform targeted at lab-on-a-chip development and showcase the MAwA’s compatibility with existing microfluidic systems.

关键词： waveguide fluid cavity