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Towards implementation of alloy-specific thermo-fluid modelling for laser powder-bed fusion of mg alloys

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Journal of magnesium and Alloys 2024年第6期12卷 2327-2344页

作者： mohammad Hoseini-Athar mikael Ersson Peter Hedström Department of material Science and Engineering KTH Royal Institute of TechnologyStockholmSE-10044 Sweden

multi-physics thermo-fluid modeling has been extensively used as an approach to understand melt pool dynamics and defect formation as well as optimizing the process-related parameters of laser powder-bed fusion(L-PBF).However,its capabilities for being implemented as a reliable tool for material design,where minor changes in material-related parameters must be accurately captured,is still in *** the present research,first,a thermo-fluid computational fluid dynamics(CFD)model is developed and validated against experimental *** the predicted material properties of the pure mg and commercial ZK60 and WE43 mg alloys,parametric studies are done attempting to elucidate how the difference in some of the material properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the melt pool *** is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation mass *** viscosity and wider solidification range can increase the non-uniformity of temperature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and formation of ***,the WE43 alloy showed the best behavior in terms of defect formation and evaporation mass loss,providing theoretical support to the extensive use of this alloy in *** summary,this study suggests an approach to investigate the effect of materials-related parameters on L-PBF melting and solidification,which can be extremely helpful for future design of new alloys suitable for L-PBF.

关键词： mg alloys Laser powder-bed fusion(L-PBF) melt pool dynamics Computational fluid dynamics Fluid flow

Spark Plasma Sintering of mg-based Alloys:microstructure,mechanical Properties,Corrosion Behavior,and Tribological Performance

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Journal of magnesium and Alloys 2024年第2期12卷 405-442页

作者： Alessandro m.Ralls mohammadreza Daroonparvar Pradeep L.menezes Department of mechanical Engineering University of Nevada RenoRenoNV89557United States

Within the past ten years,spark plasma sintering(SPS)has become an increasingly popular process for mg *** the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the concept of Joule *** to traditional and additive manufacturing(Am)techniques,SPS gives unique control of the structural and microstructural features of mg *** doing so,their mechanical,tribological,and corrosion properties can be *** great advancements in this field have been made,these pieces of knowledge are scattered and have not been contextualized into a single *** motivation of this work is to address this scientific gap and to provide a groundwork for understanding the basics of SPS manufacturing for *** do so,the existing body of SPS mg literature was first surveyed,with a focus on their structural formation and degradation *** was found that successful mg SPS fabrication highly depended on the processing temperature,particle size,and particle *** addition of metal and ceramic composites also affected their microstructural features due to the Zener pinning *** degradative environments,their performance depends on their structural features and whether they have secondary phased *** industrial applications,SPS'd mg was found to have great potential in biomedical,hydrogen storage,battery,automotive,and recycling *** prospects to advance the field include using mg as a doping agent for crystallite size refinement and using bulk metallic mg-based glass powders for amorphous SPS *** these findings,the interactions of multi-composites on the processing-structure-property relationships of SPS mg is not well *** total,this work will provide a useful direction in the SPS field and serve as a milestone for future mg-based SPS manufacturing.

关键词： Spark plasma sintering magnesium alloys Nanocrystalline Tribology mechanical properties Corrosion

A comprehensive review on the processing-property relationships of laser strengthened magnesium

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Journal of magnesium and Alloys 2024年第1期12卷 1-34页

作者： Alessandro m.Ralls Aaksheta Agnel Pradeep L.menezes Department of mechanical Engineering University of Nevada RenoRenoNV 89557United States

Among the existing series of softer metals,magnesium(mg)has attracted much attention due to its impressive strength-to-weight ***,due to its ease of deformability,mg tends to suffer from rapid degradation in a wide variety of abrasive and electrochemical *** method of improving its surface properties is through surface modification *** the existing techniques,laser shock peening(LSP)has been one of the most widely utilized processes due to its surface-hardening-like *** this understanding,a comprehensive review has yet to exist that encapsulates the strengthening mechanism of LSP for mg and its influence in degradation *** review aims to encapsulate the existing research around the LSP field for ***,an understanding of the surface-strengthening effects in relation to its mechanical,tribological,corrosion,and tribo-corrosion characteristics is ***,the feasibility of LSP for mg materials in critical industries is also *** this work,a novel understanding of LSP for mg can be understood,which can provide a future direction for research in this field.

关键词： Laser shock peening magnesium Surface deformation Tribology microstructure

Dust particle surface potential in an argonhelium plasma using the(r,q)-distribution function

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Communications in Theoretical Physics 2024年第9期76卷 143-150页

作者： Bahaaudin m Raffah A A Abid Abdullah Khan Amin Esmaeili Yas Al-Hadeethi m N S Qureshi Department of Physics Faculty of Sciences King Abdulaziz University Lithography in Devices Fabrication and Development Research Group Deanship of Scientific ResearchKing Abdulaziz University Joint Laboratory of Plasma Application Technology Institute of Advanced Technology University of Science and Technology of China CAS Key Laboratory of Geospace Environment University of Science and Technology of China Department of Physics Zhejiang Normal University Department of Physics Graduate School of Science Tokyo Metropolitan University Department of Physics GC University

In this paper, the dust particle surface potential for argon-helium plasma is evaluated analytically and numerically in the context of negatively charged dust particles by employing a power-law(r, q)-distribution function. Recent studies have reported the argon-helium plasma and conducted a brief theoretical and experimental survey. To deepen our understanding further, this study aims to analyze the argon-helium plasma comprehensively using the same pattern but with the(r, q)-distribution function. For this purpose, the current balance equations are derived for electron, helium and argon ions, when these charge species attain the quasineutrality *** numerically examined the currents of plasma species for a broad range of effective distribution function parameters r and q. It is revealed that the surface potential of dust particles is significantly affected by the parameters r and q, helium ion-to-electron temperature ratio,argon ion-to-electron temperature ratio, and helium ion to argon ion number density ratio. By incorporating the multi-ion(argon-helium) species, the significance of low-temperature nonmaxwellian dusty(complex) plasma is briefly examined.

关键词： dust charge potential dusty plasma helium argon plasma non-maxwellian distribution plasma physics q distribution function r

A seed and soil model of loneliness in Alzheimer's disease

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Neural Regeneration Research 2024年第12期19卷 2575-2576页

作者： Hannah L.Apostolou Ian m.mcDonough Department of Psychology The University of AlabamaTuscaloosaALUSA Department of Psychology Binghamton UniversityBinghamtonNYUSA

Loneliness is classically defined as a result of perceiving a discrepancy between the desired quantity and quality of one's social life and actual social relationships(Perlman and Peplau,1984).Lifespan research has indicated older adults are among the highest risk for experiencing loneliness because their social network size decreases more frequently than that of younger adults.

关键词： Alzheimer younger soil

Highly toxic Aβ begets more Aβ

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Neural Regeneration Research 2024年第9期19卷 1871-1872页

作者： merc m.Kemeh Noel D.Lazo Gustaf H.Carlson School of Chemistry and Biochemistry Clark UniversityWorcesterMAUSA

Alzheimer’s disease(AD)is the most common form of dementia-the 7th leading cause of death *** the tissue level,AD is characterized by the presence of extracellular amyloid plaques that are comprised primarily of the amyloid-βpeptide(Aβ),and by intraneuronal neurofibrillary tangles composed of *** genetics of early-onset AD and longitudinal brain-imaging studies of late-onset AD indicate that extracellular Aβdeposition,in general,precedes neurofibrillary tangle formation in neurons(Hampel et al.,2021;Young-Pearse et al.,2023).

关键词： Aβ tau Alzheimer death

Neurovascular unit on a chip: the relevance and maturity as an advanced in vitro model

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Neural Regeneration Research 2024年第6期19卷 1165-1166页

作者： Sujey Palma-Florez Anna Lagunas mònica mir Nanobioengineering Group Institute for Bioengineering of Catalonia (IBEC) Barcelona Institute of Science and Technology (BIST) Department of Electronics and Biomedical Engineering University of Barcelona CIBER-BBN ISCIII

The brain is a high-energy demanding organ, consuming around 20% of the metabolic energy generated. To fulfill this demand, cerebral blood flow(CBF) supplies oxygen and glucose continuously through the intricate network of cerebral blood vessels. Although for many years brain activity and blood flow were conceived as independent processes, mRI-based functional brain imaging demonstrated that there is a coupling between them,

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Assessment of spongy moth infestation impacts on forest productivity and carbon loss using the Sentinel-2 satellite remote sensing and eddy covariance flux data

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Ecological Processes 2024年第2期13卷 231-245页

作者： Nur Hussain Alemu Gonsamo Shusen Wang m.Altaf Arain School of Earth Environment and Society and McMaster Centre for Climate Change Mc Master University Canada Centre for Remote Sensing Natural Resources Canada

Background Deciduous forests in eastern North America experienced a widespread and intense spongy moth（Lymantria dispar） infestation in 2021. This study quantified the impact of this spongy moth infestation on carbon（C） cycle in forests across the Great Lakes region in Canada, utilizing high-resolution（10 × 10 m2） Sentinel-2 satellite remote sensing images and eddy covariance（EC） flux data. Study results showed a significant reduction in leaf area index（LAI） and gross primary productivity（GPP） values in deciduous and mixed forests in the region in *** Remote sensing derived, growing season mean LAI values of deciduous（mixed） forests were 3.66（3.18）, 2.74（2.64）, and 3.53（2.94） m2m-2in 2020, 2021 and 2022, respectively, indicating about 24（14）% reduction in LAI, as compared to pre-and post-infestation years. Similarly, growing season GPP values in deciduous（mixed） forests were 1338（1208）, 868（932）, and 1367（1175） g C m-2, respectively in 2020, 2021 and 2022, showing about 35（22）% reduction in GPP in 2021 as compared to pre-and post-infestation years. This infestation induced reduction in GPP of deciduous and mixed forests, when upscaled to whole study area（178,000 km2）, resulted in 21.1（21.4） mt of C loss as compared to 2020（2022）, respectively. It shows the large scale of C losses caused by this infestation in Canadian Great Lakes *** The methods developed in this study offer valuable tools to assess and quantify natural disturbance impacts on the regional C balance of forest ecosystems by integrating field observations, high-resolution remote sensing data and models. Study results will also help in developing sustainable forest management practices to achieve net-zero C emission goals through nature-based climate change solutions.

关键词： Spongy moth Infestation Carbon Gross ecosystem productivity Leaf area index Temperate forest Remote sensing Sentinel-2 Eddy covariance

Hydroxytyrosol and Parkinson's disease:protective actions against alpha-synuclein toxicity

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Neural Regeneration Research 2024年第7期19卷 1427-1428页

作者： Ruth Hornedo-Ortega Ana m.Espinosa-Oliva Departamento de Nutrición y Bromatología Toxicología y Medicina LegalFacultad de FarmaciaUniversidad de SevillaSevilleSpain Instituto de Biomedicina de Sevilla IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de SevillaSevillaSpain Departamento de Bioquímica y Biología molecular Facultad de FarmaciaUniversidad de SevillaSevillaSpain

Parkinson’s disease:Parkinson’s disease(PD) is the second most prevalent neurodegenerative disease,after Alzheimer’s disease,affecting 1%of the general population over the age of *** to data from the World Health Organization(WHO),its prevalence has doubled in the past 25 *** 2019,global estimates indicated over 8.5 million individuals with PD and it is suggested that PD caused 329000 deaths,an increase of over 100% since 2000(WHO,2022).

关键词： protective Alzheimer prevalence