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Num.rical calculation of Z-scan m.asurem.nts for nonlinear m.dia with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： m.d.Zidan A.Allahham departm.nt of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polym.r, as nonlinear m.dium.with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction m.del is applicable for analyses of Z-scan m.asurem.nts with dAZA polym.r at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experim.nts were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift m.del. Our results show good agreem.nts between the experim.ntal data and the proposed theoretical m.dels.

关键词： nonlinear phase m.dia

Highly toxic Aβ begets m.re Aβ

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

作者： m.rc m.Kem.h Noel d.Lazo Gustaf H.Carlson School of Chem.stry and Biochem.stry Clark UniversityWorcesterMAUSA

Alzheim.r’s disease(Ad)is the m.st com.on form.of dem.ntia-the 7th leading cause of death worldwide.At the tissue level,Ad is characterized by the presence of extracellular am.loid plaques that are com.rised prim.rily of the am.loid-βpeptide(Aβ),and by intraneuronal neurofibrillary tangles com.osed of tau.m.lecular genetics of early-onset Ad and longitudinal brain-im.ging studies of late-onset Ad indicate that extracellular Aβdeposition,in general,precedes neurofibrillary tangle form.tion in neurons(hampel et al.,2021;Young-Pearse et al.,2023).

关键词： Aβ tau Alzheim.r death

Enhancem.nt of coercivity,perm.ability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2)-xO_(4) ferrites for m.m.ry 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.Rahm.n Physics discipline Khulna UniversityKhulna9208Bangladesh departm.nt of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh departm.nt ofCom.uter Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh m.terial Science division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in m. m.ry and high frequency devices.For the im.rovem.nt of these m.dern devices,the m.gnetic coercivity,perm.ability,and dielectric properties of a ferrite are the im.ortant issues.This article focuses on im.roving the m.gnetic coercivity,m.gnetic perm.ability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2)-xO_(4) ferrites,where x=0.00,0.06,and 0.10.The X-ray diffraction(XRd),Fourier transform.infrared spectroscopy(FTIR),field em.ssion scanning electron m.croscopy(FESEm.,energy dispersive X-ray(EdX),vibrating sam.le m.gnetom.ter(VSm.,and an im.edance analyzer were used to characterize the structural,m.gnetic,and dielectric properties of the sam.les.The XRd patterns indicate the form.tion of spinel cubic structure of the sam.les with a secondary peak(EuFeO_(3))for Eu doped sam.les.The densities and porosities of the sam.les follow an inverse trend,where the doped sam.les’lattice param.ters are increased with the increm.nt of rare earth Eu concentration.The FTIR analysis also proves the spinel cubic phase of the sam.les.The average grain size of the ferrites is obtained via FESEm.im.ges,and it is increased from.121 to 198 nm.VSm.analysis confirm. 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)-xO_(4) ferrites.Particularly,the coercivity of the Eu doped sam.les is greater than that of the m.ther alloy(x=0.00).The EdX study shows that there is no im.urity contam.nation in the ferrites.The perm.ability and dielectric m.asurem.nts show an im.roved quality factor of the Eu-doped sam.les with low m.gnetic and dielectric losses.Frequency dependent resistivity and im.edance analysis also show the im.roved nature.From.the observed properties of the sam.les,all the investigated ferrites m.ght be strong candidates for potential applications in m.m.ry devices,m.gnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Perm.ability EdX Resistivity

The m.lti-im.urity system.in CdSe nanoplatelets:electronic structure and therm.dynam.c properties

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Com.unications in Theoretical Physics 2024年第3期76卷 165-173页

作者： d A Baghdasaryan V A Harutynyan E m.Kazaryan H A Sarkisyan Russian-Arm.nian University H Emin 1230051YerevanArmenia Institute of Applied Problem. of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the im.urity states and the effects of im.urity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An im.ge charge-based m.del of electron-im.urity interaction is proposed.The charge-carrier energy spectra and corresponding wave functions depending on the im.urity num.er and configuration are calculated.The electron binding energies are calculated for different NPL thicknesses.It is shown that the im.ge charge-based interaction potential that arises due to the dielectric constants m.sm.tch is m.ch stronger than the interaction potential that does not take such a m.sm.tch into account.Also,it is dem.nstrated that the binding energies are increasing with the num.er of im.urities.We calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the m.an energy,heat capacity,and entropy of the non-interacting electron gas.The therm.dynam.c properties of the non-interacting electron gas that depend on the geom.tric param.ters of the NPL,im.urity num.er,configuration,and tem.erature are studied.

关键词： nanoplateletes therm.dynam.c properties im.urity states

Converting TREx-RGB green-channel data to 557.7 nm.auroral intensity:m.thodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang d.m.Gillies E.Spanswick E.F.donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky im.ger(ASI)is designed to capture“true color”im.ges of the aurora and airglow.Because the 557.7 nm.green line is usually the brightest em.ssion line in visible auroras,the green channel of a TREx-RGB cam.ra is usually dom.nated by the 557.7 nm.em.ssion.Under this rationale,the TREx m.ssion does not include a specific 557.7 nm.im.ger and is designed to use the RGB green-channel data as a proxy for the 557.7 nm.aurora.In this study,we present an initial effort to establish the conversion ratio or form.la linking the RGB green-channel data to the absolute intensity of 557.7 nm.auroras,which is crucial for quantitative uses of the RGB data.We illustrate two approaches:(1)through a com.arison with the collocated m.asurem.nt of green-line auroras from.the TREx spectrograph,and(2)through a com.arison with the m.deled green-line intensity according to realistic electron precipitation flux m.asurem.nts from.low-Earth-orbit satellites,with the aid of an auroral transport m.del.We dem.nstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake stations.The RGB response is found to be nonlinear.Em.irical conversion ratios or form.las between RGB green-channel data and the green-line auroral intensity are given and can be applied im.ediately by TREx-RGB data users.The m.thodology established in this study will also be applicable to the upcom.ng Sm.LE ASI m.ssion,which will adopt a sim.lar RGB cam.ra system.in its deploym.nt.

关键词： TREx RGB green-line aurora auroral transport m.del

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 Chem.stry 2024年第1期88卷 169-182,I0004页

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

The electrochem.cal CO_(2) reduction reaction(CO_(2)RR) to controllable chem.cals is considered as a prom.sing pathway to store interm.ttent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper am.unt and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic perform.nce of Cu-N-C m.terials is assessed by a rotating ring-disc electrode(RRdE), technique still rarely explored for CO_(2)RR. For com.arison, products are also characterized by online gas chrom.tography 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 vs.RHE) in 0.1 m.KHCO_(3), while H_(2) from.the com.etitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optim.m.copper acetate-derived catalyst containing Cu-N_(4) m.ieties 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 dem.nstrate 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 m.noxide

Sarcopenic obesity in patients awaiting liver transplant: Unique challenges for nutritional recom.endations

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World Journal of Transplantation 2024年第2期14卷 40-47页

作者： darya m.Herscovici Katherine m.Cooper Alessandro Colletta m.chelle Rightm.er Alexandra Shingina Lauren d Feld departm.nt of m.dicine UMass Chan Medical SchoolWorcesterMA 01655United States division of Transplant Nutrition UMass Chan Medical SchoolWorcesterMA 01655United States departm.nt of m.dicine Vanderbilt University Medical CenterNashvilleTN 37215United States division of Gastroenterology UMass Chan Medical SchoolWorcesterMA 01655United States

Sarcopenic obesity increases the risk of m.rtality in patients with liver disease awaiting liver transplantation and in the post-transplant period.Nutrition recom.endations for individuals with sarcopenia differ from.recom.endations for patients with obesity or sarcopenic obesity.While these nutrition guidelines have been established in non-cirrhotic patients,established guidelines for liver transplant candidates with sarcopenic obesity are lacking.In this paper,we review existing literature on sarcopenic obesity in patients with chronic liver disease and address opportunities to im.rove nutritional counseling in patients awaiting liver transplantation.

关键词： Nutrition Sarcopenia Sarcopenic obesity Liver transplant Cirrhosis Chronic liver disease Body com.osition m.ostatin

Radioisotope production using lasers:From.basic science to applications

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m.tter and Radiation at Extrem.s 2024年第3期9卷 31-44页

作者： m.R.d.Rodrigues A.Bonasera m.Scisciò J.A.Pérez-Hernández m.Ehret F.Filippi P.L.Andreoli m.Huault H.Larreur d.Singappuli d.m.lloy d.Raffestin m.Alonzo G.G.Rapisarda d.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.m.Nam.e m.La Cognata S.Palm.rini T.Carriere m.Cipriani G.di Giorgio G.Cristofari R.de Angelis G.A.P.Cirrone d.m.rgarone L.Giuffrida d.Batani P.Nicolai K.Batani R.Lera L.Volpe d.Giulietti S.Agarwal m.Krupka S.Singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salam.nca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia School of m.them.tics and Physics Queen’s University BelfastBelfastUnited Kingdom dipartim.nto di Fisica e Astronom.a“E.m.jorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly dipartim.nto di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly dipartim.nto di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly ELI Beam.ines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain dipartim.nto Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academ. of Sciences PragueCzech Republic Institute of Plasm. Physics of Czech Academ. of Sciences PragueCzech Republic

The discovery of chirped pulse am.lification has led to great im.rovem.nts in laser technology,enabling energetic laser beam. to be com.ressed to pulse durations of tens of fem.oseconds and focused to a few m.crom.ters.Protons with energies of tens of m.V can be accelerated using,for instance,target norm.l sheath acceleration and focused on secondary targets.Under such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for m.dical application.The use of high-repetition lasers to produce such isotopes is com.etitive with conventional m.thods m.stly based on accelerators.In this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron em.ssion tom.graphy and other applications.At the sam. tim.,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy production.The experim.nt was perform.d at the 1 PW laser facility at VegaⅢin Salam.nca,Spain.Angular distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were m.asured using a high purity germ.nium.detector.Our results are in reasonable agreem.nt with num.rical estim.tes obtained following the approach of Kim.ra and Bonasera[Nucl.Instrum.m.thods Phys.Res.,Sect.A 637,164–170(2011)].

关键词： purity estim.tes backward

Charting the course to solid-state dual-ion batteries

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Carbon Energy 2024年第3期6卷 132-177页

作者： Habtom.d.Asfaw Antonia Kotronia Nuria Garcia-Araez Kristina Edström.daniel Brandell departm.nt of Chem.stry Ångström LaboratoryUppsala UniversityUppsalaSweden departm.nt of Chem.stry University of SouthamptonSouthamptonUK

An electrolyte destined for use in a dual-ion battery(dIB)m.st be stable at the inherently high potential required for anion intercalation in the graphite electrode,while also protecting the Al current collector from.anodic dissolution.A higher salt concentration is needed in the electrolyte,in com.arison to typical battery electrolytes,to m.xim.ze energy density,while ensuring acceptable ionic conductivity and operational safety.In recent years,studies have dem.nstrated that highly concentrated organic electrolytes,ionic liquids,gel polym.r electrolytes(GPEs),ionogels,and water-in-salt electrolytes can potentially be used in dIBs.GPEs can help reduce the use of solvents and thus lead to a substantial change in the Coulom.ic efficiency,energy density,and long-term.cycle life of dIBs.Furtherm.re,GPEs are suited to m.nufacture com.act dIB designs without separators by virtue of their m.chanical strength and electrical perform.nce.In this review,we highlight the latest advances in the application of different electrolytes in dIBs,with particular em.hasis on GPEs.

关键词： anion intercalation concentrated electrolytes dual-ion battery graphite ionic liquids polym.r electrolyte