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Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIn m.R.nURGALIEV A.R.nEmETS I.A.ZEmTSOV S.d.SUnTSOV T.B.mYALTOn d.S.SERGEEV n.A.SOLOVEV d.V.SARYCHEV d.V.RYJAKOV S.n.TUGARInOV n.n.nAUmEnKO national Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman moscow State Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia JSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.d.Hossain m.S.Sikder m.n.I.Khan m.R.Rahman Physics discipline Khulna UniversityKhulna9208Bangladesh department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRd),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EdX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRd patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EdX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EdX Resistivity

numerical Analysis of Permeability of Functionally Graded Scaffolds

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Fluid dynamics and materials Processing 2024年第7期20卷 1463-1479页

作者： Bratsun d. Elenskaya n. Siraev R. Tashkinov m. Laboratory of mechanics of Biocompatible materials and devices Perm National Research Polytechnic University Perm 614990 Russian Federation

In this work, we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion bioreactor. We consider two popular solid matrix designs based on triply periodic minimal surfaces, the Schwarz P (primitive) and d (diamond) surfaces, which enable the creation of materials with controlled porosity gradients. The latter property is crucial for regulating the shear stress field in the pores of the scaffold, which makes it possible to control the intensity of cell growth. The permeability of functionally graded materials is studied within the framework of both a microscopic approach based on the navier-Stokes equation and an averaged description of the liquid filtration through a porous medium based on the equations of the darcy or Forchheimer models. We calculate the permeability coefficients for both types of solid matrices formed by Schwarz surfaces, study their properties concerning forward and reverse fluid flows, and determine the ranges of Reynolds number for which the description within the darcy or Forchheimer model is applicable. Finally, we obtain a shear stress field that varies along the sample, d.m.n.trating the ability to tune spatially the rate of tissue growth. © This work is licensed under a Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

关键词： filtration models functionally graded materials Porous media scaffolds

Greatly enhanced corrosion/wear resistances of epoxy coating for mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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Journal of magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.Li J.H.Chu m.m.Li d.n.Zou L.B.Tong School of metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced design and.m.n.facturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of mg alloys.

关键词： mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

design of a novel Exoskeleton with Passive magnetic Spring Self-locking and Spine Lateral Balancing

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Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon F.Rodríguez-León Betsy d.m.Chaparro-Rico daniele Cafolla Francesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico department of mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly Faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive degrees of Freedom(doF).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight *** paper reports specific models and simulations to d.m.n.trate the feasibility and effectiveness of the proposed *** experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling *** obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Polio eradication surveillance in Sri Lanka,2019-2023

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Asian Pacific Journal of Tropical medicine 2024年第6期17卷 268-272页

作者： m.A.Y.Fernando n.S.madarasinghe C.Rangana n.Weerasinghe d.C.U.d.Weligamage J.I.Abeynayake department of medical microbiology and Immunology Faculty of MedicineUniversity of ColomboSri Lanka department of Virology Medical Research InstituteColombo 08Sri Lanka medical Research Institute Colombo 08Sri Lanka

Objective:To evaluate the polio laboratory surveillance carried out from January,2019 to may,2023 by the Polio Regional Reference Laboratory,Sri ***:This retrospective study analyzed all stool samples received under the acute flaccid paralysis(AFP)and immunodeficient vaccine-derived poliovirus(VdPV)surveillance at Polio Regional Reference Laboratory,Sri Lanka from January,2019 to may,*** results of the testing methodologies were extracted from the laboratory data system,i.e.,poliovirus virus isolation,intra-typic differentiation/VdPV real time reverse transcriptase polymerase chain reaction(ITd/VdPV rRTPCR)and sequencing,along with the data on timing of reporting results,stool adequacy and *** was analyzed using descriptive ***:A total of 2141 stool samples from 1644 cases were received for AFP surveillance from Sri Lanka(93.61%),maldives(1.52%),and immunodeficient VdPV(4.86%)*** polioviruses(19/1644,1.15%)and non-polio enteroviruses(73/1644,4.44%)were isolated,while Sabin-like 3 virus was detected in majority(12/19,63.15%)among the poliovirus *** polioviruses or circulating VdPVs were not detected among the *** all years of the study,the non-polio AFP detection rate was>1/100000 in children aged less than 15 years,whereas stool adequacy rate was>80%.All results were reported within 14 days of receipt,ensuring timely reporting as per global ***:The Polio Regional Reference Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the country through its robust laboratory surveillance,while adhering to the surveillance ***-detection of wild polioviruses and circulating VdPV during the study period reinforces the polio-free status in the country.

关键词： Poliovirus Polio laboratory surveillance Regional reference laboratory Polio eradication

Solar-assisted photocatalytic water splitting using defective UiO-66 solids from modulated synthesis

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nano Research 2024年第5期17卷 4134-4150页

作者： Celia m.Rueda-navarro maría Cabrero-Antonino Paula Escamilla Valentín díez-Cabanes dong Fan Pedro Atienzar Belén Ferrer Ignacio Vayá Guillaume maurin Herme G.Baldoví Sergio navalón departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de Ciencia molecular(ICmOL) Universitat de ValènciaPaterna 46980Spain ICGm Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPV-CSIC) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

metal-organic frameworks(mOFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative UiO-66 organic modulators for synthesizing visible light responsive UiO-66(Zr)-X(X:nH_(2) or nO_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different UiO-66(Zr)-X(X:nH_(2) or nO_(2))solid ***-66(Zr)-nH_(2) was the most active photocatalyst,followed by UiO-66(Zr)-nO_(2),both prepared with 12 equivalents of AA with respect to the organic *** UiO-66(Zr)-nH_(2) solid was more active than the parent mOF in photocatalytic overall water splitting(OWS)(H_(2) and O_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(UV-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPS),laser flash photolysis(LFP),electron spin resonance(ESR),photoluminescence and photoelectrochemical measurements together with density functional theory(dFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker UiO-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(mOFs) UiO-66 materials carboxylic acid modulators water splitting solar light

Single atom Cu-n-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez m.Gutiérrez-Roa C.Giménez-Rubio d.Ríos-Ruiz P.Arévalo-Cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro d.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-n-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-n-C materials is assessed by a rotating ring-disc electrode(RRdE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-nC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 m KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-n_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results d.m.n.trate that RRdE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-n-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt m.Gyrdymov S.Zähter P.Tavana m.m.Günther n.Bukharskii n.Borisenko J.Jacoby X.F.Shen A.Pukhov n.E.Andreev O.n.Rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany national Research nuclear University mEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (dLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of dLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 meV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHm of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, dLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical