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Friction 2024年第3期12卷 375-395页

作者： Xiao YANG Heli LIU Lemeng ZHANG Yiran HU Denis J.POLITIS Mohammad M.GHARBI Liliang WANG Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Mechanical and Manufacturing Engineering University of CyprusNicosia 1678Cyprus Quaker Houghton Deutschland gmbh Dortmund 44319Germany

The accurate representation of tribological boundary conditions at the tool–workpiece interface is crucial for analysis and optimization of formability,material flow,and surface quality of components during metal forming *** has been found that these tribological conditions vary spatially and historically with process parameters and contact *** time-dependent tribological behaviours are also known as transient tribological phenomena,which are widely observed during forming processes and many other manufacturing application ***,constant friction values are usually assigned to represent complex and dynamic interfacial conditions,which would introduce deviations in the relevant *** this paper,transient tribological phenomena and the contemporary understanding of the interaction between friction and wear are reviewed,and it has been found that these phenomena are induced by the transitions of friction mechanisms and highly dependent on complex loading conditions at the *** modelling techniques for transient behaviours for metal forming applications are also *** accurately describe the evolutionary friction values and corresponding wear during forming,the advanced interactive friction modelling has been established for different application scenarios,including lubricated condition,dry sliding condition(metal-on-metal contact),and coated system.

关键词： transient tribological phenomena interactive friction mechanism modelling techniques metal forming

Recycled graphite for more sustainable lithium-ion batteries

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Carbon Energy 2024年第5期6卷 15-24页

作者： Mayokun Olutogun Anna Vanderbruggen Christoph Frey Martin Rudolph Dominic Bresser Stefano Passerini Helmholtz Institute Ulm(HIU) Ulm Germany Karlsruhe Institute of Technology(KIT) KarlsruheGermany Helmholtz Zentrum Dresden-Rossendorf(HZDR) Helmholtz Institute Freiberg for Resource Technology(HIF)FreibergGermany ProGraphite gmbh UntergriesbachGermany Chemistry Department Sapienza University of RomeRomeItaly

The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the *** great success,however,urgently calls for the efficient recycling of LIBs at the end of their ***,we describe a froth flotation-based process to recycle graphite—the predominant active material for the negative electrode—from spent LIBs and investigate its reuse in newly assembled *** has been found that the structure and morphology of the recycled graphite are essentially unchanged compared to pristine commercial anode-grade graphite,and despite some minor impurities from the recycling process,the recycled graphite provides a remarkable reversible specific capacity of more than 350 mAh g^(−1).Even more importantly,newly assembled graphite‖NMC532 cells show excellent cycling stability with a capacity retention of 80%after 1000 cycles,that is,comparable to the performance of reference full cells comprising pristine commercial graphite.

关键词： anode graphite lithium-ion battery recycling sustainability

Mechanism of cross-level settlements and void accumulation of wide and conventional sleepers in railway ballast

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Railway Engineering Science 2024年第3期32卷 361-383页

作者： Olga Nabochenko Mykola Sysyn Norman Krumnow Szabolcs Fischer Institute of Railway Systems and Public Transport Technical University of DresdenDresdenGermany Rhomberg Sersa Deutschland gmbh BerlinGermany Central Campus Győr Széchenyi István UniversityGyorHungary

The cross-level and twist irregularities are the most dangerous irregularity types that could cause wheel unloading with the risk of derailments and additional maintenance ***,the mechanism of the irregularities initiation and development is *** motivation of the present study was the previous experimental studies on the application of wide sleepers in the ballasted *** long-term track geometry measurements with wide sleepers show an enormous reduction of the vertical longitudinal irregularities compared to the conventional ***,wide sleepers had higher twist and cross-section level *** present paper aims to explain the phenomenon by discrete element method(DEM)modeling the development process of sleeper inhomogeneous support at cross-level depending on the sleeper *** DEM simulations show that the maximal settlement intensity is up to 3.5 times lower for a wide sleeper in comparison with the conventional ***,the cross-level differential settlements are almost the same for both *** particle loading distribution after all loading cycles is concentrated on the smaller area,up to the half sleeper length,with fully unloaded zones under sleeper *** flow limitation under the central part of the sleeper could improve the resilience of wide sleepers to the development of cross-level *** mechanism of initiation of the cross-level irregularity is proposed,which assumes the loss of sleeper support under sleeper *** further growth of inhomogeneous settlements along the sleeper is assumed as a result of the interaction of two processes:ballast flow due to dynamic impact during void closing and on the other side high pressure due to the concentration of the pressure under the middle part of the *** DEM simulation results support the assumption of the mechanism and agree with the experimental studies.

关键词： Wide sleeper Ballasted track Sleeper support inhomogeneity Sleeper foot form Discrete element modeling Void accumulation

Metabolic characterization of selected probiotic consortia during gluten and wheat bread simulated digestion

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Food Science and Human Wellness 2024年

作者： Mirco Vacca Giuseppe Celano Olga Nikoloudaki Bodo Speckmann Francesco Maria Calabrese Marco Gobbetti Maria de Angelis Faculty of Science and Technology， Free University of Bozen Evonik Operations gmbh Department of Soil Plant and Food Sciences， University of Bari Aldo Moro

While exerting their metabolic activities in the gastrointestinal milieu， probiotics impact the host well-being by boosting immunity， treating metabolic disorders， and modulating microbiota and metabolome. Due to the high incidence of gluten-based disorders， the present work aims to deeply explore the metabolism of two selected microbial consortia (MCs) during gluten digestion under simulated gastrointestinal conditions. Featured by high protease and peptidase activity， both MCs accounted for different lactic acid bacteria and Bacillus strains that were combined with two commercial protease enzymes. Gluten substrates were used as purified extracts， white and whole wheat breads. Control samples， instead， relied onto the microbial enzyme lack. Twenty-four hours of simulated digestion were sufficient to completely hydrolyze gluten in one of the two MC-containing experimental sets， and the relative 48 h-digested extract did not alter the cytokine expression in duodenal biopsies from celiac disease (CeD) patients. When digested samples were assayed for antioxidant and phytase activities， microbial enzymes demonstrated to significantly improve both ABTS and DPPH values and to decrease the phytic acid concentration. The inspection of the free amino acid profiles allowed for distinguishing the two MCs， whereas the detection of a heterogeneous panel of volatile organic compounds supported the presence/activity of microbial enzymes without statistically significant differences between MCs. As functional contribution， digested extracts with MCs also proved to reduce the inflammatory cytokine concentrations in cell lines exposed to lipopolysaccharide trigger. Therefore， in line with studies exploring novel adjuvant therapies， the present innovative probiotic consortium featured by high gluten-hydrolyzing metabolism also showed the capability to improve various parameters usually found to be altered in patients affected by gluten-based disorders or CeD.

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The effect of Laves phases and nano-precipitates on the electrochemical corrosion resistance of Mg-Al-Ca alloys under alkaline conditions

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Journal of Magnesium and Alloys 2024年第6期12卷 2447-2461页

作者： Markus Felten Veronika Chaineux Siyuan Zhang Ali Tehranchi Tilmann Hickel Christina Scheu Joshua Spille Marta Lipińska-Chwałek Joachim Mayer Benjamin Berkels Marcus Hans Imke Greving Silja Flenner Sandra Sefa Daniela Zander Chair of Corrosion and Corrosion Protection RWTH Aachen UniversityAachen 52072 Germany Max-Planck-Institut für Eisenforschung gmbh Düsseldorf 40237 Germany Central Facility for Electron Microscopy RWTH Aachen UniversityAachen 52074 Germany Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum Jülich GmbHJülich 52428Germany Mathematical Image and Signal Processing Aachen Institute for Advanced Study in Computational Engineering ScienceRWTH Aachen UniversityAachen 52062 Germany Materials Chemistry RWTH Aachen UniversityAachen 52074 Germany Institute of Materials Physics Helmholtz-Zentrum HereonGeesthacht 21502 Germany

The electrochemical corrosion mechanisms of Mg alloys were extensively studied in previous investigations of different chemical com-positions,modified surface states and various electrolyte ***,recent research focused on the active state of Mg dissolution,leading to unresolved effects of secondary phases adjacent to a stableα-solid solution passive *** present study investigates the fundamental electrochemical corrosion mechanisms of three different Laves phases with varying phase morphologies and phase fractions in the passive state of Mg-Al-Ca *** microstructure was characterized by(transmission-)electron microscopy and synchrotron-based transmission X-ray *** electrochemical corrosion resistance was determined with a standard three-electrode setup and advanced in-situ flow cell measurements.A new electrochemical activity sequence(C15>C36>α-Mg>C14)was obtained,as a result of a stable passive layer formation on theα-solid ***,nm-scale Mg-rich precipitates were identified within the Laves phases,which tend to inhibit the corrosion kinetics.

关键词： Laves phase STEM Magnesium Corrosion Passive layer

Cellular precision modulation of JAK1:tailoring therapies for allergic lung inflammation

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2843-2844页

作者： Xiaocheng Yan Siegfried Ussar Research Unit Adipocytes&Metabolism(ADM) Helmholtz Diabetes CenterHelmholtz Zentrum MünchenGerman Research Center for Environmental Health GmbH85764 NeuherbergGermany German Center for Diabetes Research(DZD) 85764 NeuherbergGermany

In a recent publication published in Cell,Tamari et *** a previously unrecognized role of JAK1 signaling in vagal sensory neurons regulating the immune response to allergic lung inflammation.1 The authors show that sensory neuromodulation could be an important therapeutic avenue for the treatment of lung *** is now well established that the number of patients suffering from allergic disorders,like those suffering from obesity and the metabolic syndrome,is rapidly increasing world-wide,accelerating the burden on individual health and healthcare ***,basic and clinical researchers urgently need to develop novel therapeutics and approaches to limit or prevent disease development or progression.

关键词： JAK1 allergic lung

Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power Laser Science and Engineering 2024年第3期12卷 134-145页

作者： M.Füle A.P.Kovács T.Gilinger M.Karnok P.Gaál S.Figul G.Marowsky K.Osvay National Laser-Initiated Transmutation Laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ELI ALPS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced Microfluidic Systems gmbh GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

Impact of T_(i)/T_(e )ratio on ion transport based on EAST H-mode plasmas

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Plasma Science and Technology 2024年第4期26卷 68-78页

作者：刘建文臧庆梁云峰陈佳乐邬潇河 Alexander KNIEPS 扈嘉辉金仡飞张斌储宇奇刘海庆吕波段艳敏李妙辉陈颖杰龚先祖 the EAST Team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Forschungszentrum Jülich gmbh Institut für Energie-und Klimaforschung-PlasmaphysikPartner of the Trilateral Euregio Cluster(TEC)Jülich 52425Germany

At the EAST tokamak, the ion temperature(T_(i)) is observed to be clamped around 1.25 keV in electron cyclotron resonance(ECR)-heated plasmas, even at core electron temperatures up to 10 keV(depending on the ECR heating power and the plasma density). This clamping results from the lack of direct ion heating and high levels of turbulence-driven transport. Turbulent transport analysis shows that trapped electron mode and electron temperature gradient-driven modes are the most unstable modes in the core of ECR-heated H-mode plasmas. Nevertheless, recently it was found that the T_(i)/T_(e)ratio can increase further with the fraction of the neutral beam injection(NBI) power, which leads to a higher core ion temperature(Ti0). In NBI heating-dominant H-mode plasmas, the ion temperature gradient-driven modes become the most unstable ***, a strong and broad internal transport barrier(ITB) can form at the plasma core in high-power NBI-heated H-mode plasmas when the T_(i)/T_(e)ratio approaches ~1, which results in steep core Teand Tiprofiles, as well as a peaked neprofile. Power balance analysis shows a weaker Teprofile stiffness after the formation of ITBs in the core plasma region, where Ticlamping is broken,and the core Tican increase further above 2 keV, which is 80% higher than the value of Ticlamping in ECR-heated plasmas. This finding proposes a possible solution to the problem of Ticlamping on EAST and demonstrates an advanced operational regime with the formation of a strong and broad ITB for future fusion plasmas dominated by electron heating.

关键词： ion temperature clamping transport neutral beam injection stiffness internal transport barrier

Improved training framework in a neural network model for disruption prediction and its application on EXL-50

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Plasma Science and Technology 2024年第5期26卷 29-39页

作者：蔡剑青梁云峰 Alexander KNIEPS 齐东凯王二辉向皓明廖亮黄杰阳杰黄佳刘建文 Philipp DREWS 徐帅顾翔高轶琛罗宇李直 the EXL-50 Team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Forschungszentrum Jülich gmbh Institut für Energie-und Klimaforschung-PlasmaphysikPartner of the Trilateral Cluster(TEC)Jülich 52425Germany ENN Science and Technology Development Co. LtdLangfang 065001People’s Republic of China

A neural network model with a classical annotation method has been used on the EXL-50tokamak to predict impending ***,the results revealed issues of overfitting and overconfidence in predictions caused by inaccurate *** mitigate these issues,an improved training framework has been *** this approach,soft labels from previous training serve as teachers to supervise the further learning process;this has lead to a significant improvement in predictive model ***,this enhancement is primarily attributed to the coupling effect of the soft labels and correction *** improved training framework introduces an instance-specific label smoothing method,which reflects a more nuanced model assessment on the likelihood of a *** presents a possible solution to effectively address the challenges associated with accurate labeling across different machines.

关键词： neural network disruption soft label EXL-50 tokamak

Application of Bioengineering in Construction

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Open Journal of Civil Engineering 2024年第3期14卷 391-404页

作者： Sassan Mohasseb Atiyeh Meidanchi Sonia Daneshgari Department of Energy Engineering Smteam GmbH Zurich Switzerland Department of Leadership Western Trinity University Vancouver Canada

Bio-cement and bio-concrete are innovative solutions for sustainable construction, aiming to reduce environmental impact while maintaining the durability and versatility of building materials. Bio-cement is an eco-friendly alternative to traditional cement, produced through Microbially Induced Calcium Carbonate Precipitation (MICP), which mimics natural biomineralization processes. This method reduces CO2 emissions and enhances the strength and durability of construction materials. Bio-concrete incorporates bio-cement into concrete, creating a self-healing material. When cracks form in bio-concrete, dormant bacteria within the material become active in the presence of water, producing limestone to fill the cracks, extending the material’s lifespan and reducing the need for repairs. The environmental impact of traditional cement production is significant, with cement generation accounting for up to 8% of global carbon emissions. Creative solutions are needed to develop more sustainable construction materials, with some efforts using modern innovations to make concrete ultra-durable and others turning to science to create affordable bio-cement. The research demonstrates the potential of bio-cement to revolutionize sustainable building practices by offering a low-energy, low-emission alternative to traditional cement while also addressing environmental concerns. The findings suggest promising applications in various construction scenarios, including earthquake-prone areas, by enhancing material durability and longevity through self-repair mechanisms.

关键词： Sustainable Construction Microbially Induced Calcium Carbonate Precipitation (MICP) Cement Construction Industry Microorganisms Eco-Friendly Sustainable Solution Durability Carbon Dioxide Emission (CO2)