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Simulation of Rotating Asymmetric Sideways Forces during Vertical displacement Events in CFETR

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Chinese physics Letters 2024年第8期41卷 39-44页

作者： Changzhi Jiang Shunwen Wang Zhenyu Zhou di Hu Bo Li JoREK team School of physics Beihang UniversityBeijing 100191China

Tokamak plasmas with elongated cross sections are susceptible to vertical displacement events(VDEs),which can damage the first wall via heat flux or electromagnetic(Em)*** present a 3D nonlinear reduced magnetohydrodynamic(mHD)simulation of CFETR plasma during a cold VDE following the thermal quench,focusing on the relationship among the Em force,plasma displacement,and the n=1 *** dominant mode,identified as m/n=2/1,becomes destabilized when most of the current is contracted within the q=2 *** displacement of the plasma current centroid is less than that of the magnetic axis due to the presence of SoL current in the open field line ***,the symmetric component of the induced vacuum vessel current is significantly *** direction of the sideways force keeps a constant phase approximately compared to the asymmetric component of the vacuum vessel current and the SoL current,which in turn keep in-phase with the dominant 2/1 *** amplitudes are also closely associated with the growth of the dominant *** findings provide insights into potential methods for controlling the phase and amplitude of sideways forces during VDEs in the future.

关键词： CFETR displacement vacuum

New opportunities for Neutrons in Environmental and Biological Sciences

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 179-186页

作者： Alexander Johs Shuo Qian Leighton Coates Brian H.Davison James G.Elkins Xin Gu Jennifer morrell-Falvey Hugh o'Neill Jeffrey m.Warren Eric m.pierce Kenneth Herwig oak Ridge National Laboratory Oak RidgeTN37831USA

The use of neutron methods in environmental and biological sciences is rapidly emerging and accelerating with the development of new instruments at neutron user *** article,based on a workshop held at oak Ridge National Laboratory(oRNL),offers insights into the application of neutron techniques in environmental and biological *** highlight recent advances and identify key challenges and potential future research *** include soil and rhizosphere processes,root water dynamics,plant-microbe interactions,structure and dynamics of biological systems,applications in synthetic biology and enzyme engineering,next-generation bioproducts,biomaterials and bioenergy,nanoscale structure,and fluid dynamics of porous materials in *** provide an outlook on emerging opportunities with an emphasis on new capabilities that will be enabled at the Spallation Neutron Source Second Target Station currently under design at *** mission of scientific neutron user facilities worldwide is to enable science using state-of-the-art neutron *** aim to encourage researchers in the environmental and biological research community to explore the unique capability afforded by neutrons at these facilities.

关键词： Neutrons Environment Biology Neutron imaging Neutron scattering Second Target Station(STS)

Development and testing of a high-power S-band klystron at BINp SB RAS

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Nuclear Science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnyakov S.Samoylov D.Nikiforov V.Ivanov m.Arsentyeva D.Chekmenev o.pavlov I.pivovarov Budker Institute of Nuclear physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk State University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the S-band high-power klystron,accomplished at the Budker Institute of Nuclear physics,Siberian Branch,Russian Academy of Sciences(BINp SB RAS).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 mHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

The initial stages of Li_(2)o_(2) formation during oxygen reduction reaction in Li-o_(2) batteries:The significance of Li_(2)o_(2) in charge-transfer reactions within devices

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Journal of Energy Chemistry 2024年第1期88卷 223-231,I0006页

作者： Daniela m.Josepetti Bianca p.Sousa Simone A.J.Rodrigues Renato G.Freitas Gustavo Doubek Advanced Energy Storage division LABCenter for Innovation on New EnergiesSchool of Chemical EngineeringUniversity of CampinasAv Albert Einstein 50013083-852CampinasSPBrazil Institute of physics&Department of Chemistry Laboratory of Computational MaterialsFederal University of Mato Grosso78060-900CuiabáMTBrazil

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion ***,this theoretical characteristic has not yet been converted into a real device with high *** with air contamination,metallic lithium reactivity,and complex discharge and charge reactions are the main issues for this technology.A fast and reversible oxygen reduction reaction(oRR)is crucial for good performance of secondary batteries',but the partial knowledge of its mechanisms,especially when devices are concerned,hinders further *** this perspective,the present work uses operando Raman experiments and electrochemical impedance spectroscopy(EIS)to assess the first stages of the discharge processes in porous carbon electrodes,following their changes cycle by cycle at initial operation.A growth kinetic formation of the discharge product signal(Li_(2)o_(2))was observed with operando Raman,indicating a first-order reaction and enabling an analysis by a microkinetic *** solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time *** the time constant for the anode interface reveals to remain relatively constant after the first discharge,its surface seemed to be more *** model indicated that the reaction occurs at the Li_(2)o_(2) surface,decreasing the associated resistance during the initial discharge ***,the growth of Li_(2)o_(2) forms a hetero-phase between Li_(2)o_(2)/electrolyte,while creating a more compact and homogeneous on the Li_(2)o_(2)/cathode *** methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

关键词： Li-o_(2)battery operando Raman analysis Equivalent circuit modeling Time-constant distribution

phase-field simulations of topological conservation in multi-vortex induced by surface charge in BiFeo_(3)thin films

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Journal of Advanced dielectrics 2024年第2期14卷 63-70页

作者： mengyuan Wang di Liu Jing Wang Deshan Liang Houbing Huang Advanced Research Institute of multidisciplinary Science Beijing Institute of Technology Beijing 100081P.R.China School of materials Science and Engineering Beijing Institute of Technology Beijing 100081P.R.China

The creations and manipulations of vortexes in ferroelectric materials with external stimuli are expected to be used in the design and fabrication of sensing materials and multifunctional electronic *** this work,we investigated the surface charge-induced multi-vortex evolution using the phase-field simulations in BiFeo_(3).A combination of domain morphology,polarization distribution and winding number calculation was *** results show that vortex and anti-vortex exist simultaneously in pairs,and the total value of winding numbers is always *** addition,the minimum distanceΔl between the surface charge regions is 9 nm when the vortex domains are independent of each *** work provides a reference for the manipulation of ferroelectric vortex induced by surface charges,which lays a theoretical foundation for the design and fabrication of high-density vortex memories.

关键词： Ferroelectric vortex surface charge phase-field simulations winding number

BaTio_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric properties

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Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.martínez-López m.pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández m.Reyes-pérez m.I.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.I.Dávila-pulido Academic Area of Earth Sciences and materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico metallurgy and materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTio_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,Tio_(2),Gd_(2)o_(3),and Eu_(2)o_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 mpa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)o_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTio_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the BaTio_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2Tio_(5)and monoclinic BaTi_(2)o_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTio_(3)around 716 cm^(-1)(Lo of A1 symmetry),515 cm^(-1)(To of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,o,Gd,and Eu homogeneously distributed in the BaTio_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTio_(3) Doping Gadolinium Europium Synthesis Rare earths

Investigating low dispersion isotope dissolution Lu-Hf garnet dates via in situ Lu-Hf geochronology,Kanchenjunga Himal

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Geoscience Frontiers 2024年第3期15卷 137-145页

作者： Kyle p.Larson John m.Cottle mark Button Brendan Dyck Iva Lihter Sudip Shrestha Department of Earth Environmental and Geographic SciencesUniversity of British ColumbiaOkanaganKelownaCanada Department of Earth Science University of CaliforniaSanta BarbaraUSA Fipke Laboratory for Trace Element Research University of British ColumbiaOkanaganKelownaCanada

Re-examination of three specimens from the Kanchenjunga Himal of Nepal via in situ Lu-Hf garnet geochronology yields evidence of multiple garnet growth *** analyses from grain cores in two specimens define paleozoic regressions whereas analyses from grain rims in the same specimens define low-precision regressions consistent with the timing of Himalayan *** dates contrast with previously published low dispersion,ca.290 ma isotope dissolution(ID)Lu-Hf garnet dates for the same *** of Lu and spot age distribution in representative grains from the specimens examined yields calculated dates that approximate the permian-age regressions through the original ID *** findings demonstrate that it is possible to generate low dispersion ID Lu-Hf data from multigenerational garnet with significantly different-age growth events when approximately equal proportions of the different age reservoirs are included in multi-component aliquots.

关键词： Lu-Hf geochronology In situ Lu-Hf geochronology Kanchenjunga Himal

Tribological behavior of shape-specific microplate-enriched synovial fluids on a linear two-axis tribometer

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Friction 2024年第3期12卷 539-553页

作者： Agnese FRAGASSI Antonietta GRECo martina di FRANCESCo Luca CESERACCIU Aiman ABU AmmAR Israel DVIR Thomas Lee mooRE Haytam KASEm paolo DECUZZI Laboratory of Nanotechnology for precision medicine Fondazione Istituto Italiano di TecnologiaGenova 16163Italy Department of Chemistry and Industrial Chemistry University of GenovaGenoa 16146Italy materials Characterization Facility Istituto Italiano di TecnologiaGenova 16163Italy Department of pharmaceutical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel Department of mechanical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel

Nano-and micro-particles are being increasingly used to tune interfacial frictional properties in diverse applications,from friction modifiers in industrial lubrication to enhanced biological fluids in human osteoarthritic ***,we assessed the tribological properties of a simulated synovial fluid enriched with non-spherical,poly lactic-co-glycolic acid(pLGA)microparticles(μpL)that have been previously demonstrated for the pharmacological management of osteoarthritis(oA).Three different μpL configurations were fabricated presenting a 20μm×20μm square base and a thickness of 5μm(thin,5H μpL),10μm(10H μpL),and 20μm(cubical,20H μpL).After extensive morphological and physicochemical characterizations,the apparent Young’s modulus of the μpL was quantified under compressive loading returning an average value of~6 kpa,independently of the particle ***,using a linear two-axis tribometer,the static(μ_(s))and dynamic(μ_(d))friction coefficients of the μpL-enriched simulated synovial fluid were determined in terms of particle configuration and concentration,varying from 0(fluid only)to 6×10^(5) μpL/*** particle morphology had a modest influence on friction,possibly because the μpL were fully squeezed between two mating surfaces by a 5.8 N normal load realizing boundary-like lubrication ***,friction was observed to depend on the dimensionless parameterW,defined as the ratio between the total volume of the μpL enriching the simulated synovial fluid and the volume of the fluid *** coefficients of friction were documented to grow withWreaching a plateau of μ_(s)~0.4 and μ_(d)~0.15,already at Ω~2×10^(-3).Future investigations will have to systematically analyze the effect of sliding velocity,normal load,and rigidity of the mating surfaces to elucidate in full the tribological behavior of μpL in the context of osteoarthritis.

关键词： osteoarthritis microparticles tribology synovial fluid pin on plate

Hierarchical CoFe@N-Doped Carbon Decorated Wood Carbon as Bifunctional Cathode in Wearable Zn-Air Battery

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Energy & Environmental materials 2024年第1期7卷 42-50页

作者： Kelong Ao Xiangyang Zhang Renat R.Nazmutdinov di Wang Jihong Shi Xian Yue Jianguo Sun Wolfgang Schmickler Walid A.Daoud Department of mechanical Engineering City University of Hong KongHong Kong 999077China Kazan National Research Technological University 420015 KazanRussian Federation School of Textile and Garment Anhui Polytechnic UniversityWuhu 241000China Wood materials Science Institute for Building MaterialsETH Zürich8093 ZürichSwitzerland Am Sandhaken 18 D-89069 UlmGermany

Rechargeable Zn-air batteries(ZAB)have drawn extensive attention due to their eco-friendliness and ***,the lack of high-performance and low-cost oxygen redox reactions(oER and oRR)catalysts has become one of the main stumbling blocks in their ***,we successfully fabricate a CoFe nanobubble encapsulated in nitrogen-doped carbon nanocage on wood carbon support(CoFe@NC/WC)via pyrolysis of a novel prussian blue analog(pBA)/spruce *** hierarchical CoFe@NC/WC catalyst exhibits an excellent potential difference of 0.74 V between the oER potential at 10 mA cm^(-2)and half-wave potential of oRR in 0.1 m KoH,comparable to recently reported preeminent ***,CoFe@NC/WC shows outstanding electrochemical performance in liquid ZAB,with a peak power density of 138.9 mW cm^(-2)and a specific capacity of 763.5 mAh g^(-1).more importantly,a bacterial cellulose nanofiber reinforced polyacrylic acid(BC-pAA)hydrogel electrolyte shows ultrahigh tensile-breaking stress of 1.58 *** conjunction with the as-prepared CoFe@NC/WC catalyst,BC-pAA-based wearable ZAB displays impressive rechargeability and foldability,and can power portable electronics,such as electronic timer and mobile phone,in bent *** work provides a new approach toward high-activity and low-cost catalysts for ZAB.

关键词： biomass-based catalyst DFT computation hydrogel electrolyte oxygen redox reactions wearable Zn-air battery