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Radiative decays D*(s)→ D(s)γ in covariant confined quark model

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Chinese Physics C 2024年第2期48卷 45-56页

作者： C.t.tran M.A.Ivanov P.santorelli Q.C.Vo Department of Physics HCMC University of Technology and EducationVo Van Ngan 1700000 Ho Chi Minh CityVietnam Bogoliubov Laboratory of theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia Dipartimento di fisica"E.Pancini" Universitàdi Napoli Federico ⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto Nazionale di fisica Nucleare Sezione di Napoli80126 NapoliItaly University of science 700000 Ho Chi Minh CityVietnam

Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BEsⅢ*** radiative couplings gD*Dγencoding nonperturbative QCD effects are calculated in the framework of the covariant confined quark model developed by *** compare our results with other theoretical studies and experimental *** couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).the most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QCD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QCD sum rules.

关键词： covariant quark model radiative decay charmed meson

Melting of hydrous pyroxenites with alkali amphiboles in the continental mantle:*** element compositions of melts and minerals

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Geoscience frontiers 2024年第1期15卷 50-68页

作者： stephen f.foley Isra s.Ezad school of Natural sciences Macquarie UniversityNorth RydeNew South Wales 2109Australia Research school of Earth sciences Australian National UniversityCanberraACT 2601Australia

the trace element compositions of melts and minerals from high-pressure experiments on hydrous pyroxenites containing K-richterite are presented. the experiments used mixtures of a third each of the natural minerals clinopyroxene, phlogopite and K-richterite, some with the addition of 5% of an accessory phase ilmenite, rutile or apatite. Although the major element compositions of melts resemble natural lamproites, the trace element contents of most trace elements from the three-mineral mixture are much lower than in lamproites. Apatite is required in the source to provide high abundances of the rare earth elements, and either rutile and/or ilmenite is required to provide the high field strength elements ti, Nb, ta, Zr and Hf. Phlogopite controls the high levels of Rb, Cs and *** abundances of trace elements in the various starting mixtures vary strongly because of the use of natural minerals, we calculated mineral/melt partition coefficients (DMin/melt) using mineral modes and melting reactions and present trace element patterns for different degrees of partial melting of hydrous pyroxenites. Rb, Cs and Ba are compatible in phlogopite and the partition coefficient ratio phlogopite/K-richterite is high for Ba (136) and Rb (12). All melts have low contents of most of the first row transition elements, particularly Ni and Cu ((0.1-0.01)×primitive mantle). Nickel has high DMin/melt for all the major minerals (12 for K-richterite, 9.2 for phlogopite and 5.6 for Cpx) and so behaves at least as compatibly as in melting of peridotites. fluorine/chlorine ratios in melts are high and DMin/melt for fluorine decreases in the order apatite (2.2) > phlogopite (1.5) > K-richterite (0.87). the requirement for apatite and at least one ti-oxide in the source of natural lamproites holds for mica pyroxenites that lack K-richterite. the results are used to model isotopic ageing in hydrous pyroxenite source rocks: phlogopite controls sr isotopes, so that lamproites with relatively l

关键词： Hydrous pyroxenite Lamproite trace elements Phlogopite K-richterite Apatite

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.the additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu s.M.Weng P.Li X.f.Li H.Ai H.R.Pan Z.M.sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IfsA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser fusion of China Academy of Engineering Physics MianyangSichuan 621900China state key Laboratory of High field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

the generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(tHz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or tHz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or tHz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and tHz spectral ranges.

关键词： laser ultrashort photon

Endophytic Occupation in Nodules of Rhynchosia Plants from semiarid Regions of Argentina

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Phyton-International Journal of Experimental Botany 2024年第6期93卷 1081-1099页

作者： Cinthia t.Lucero María de los Á.Ruíz fabiola Pagliero Carolina Castaño Mariela L.Ambrosino Graciela s.Lorda facultad de Ciencias Exactas y Naturales Universidad Nacional de La PampaRuta Nacional 35km 330Santa RosaLa PampaCP6300Argentina INtA EEA Anguil“Ing.Agr.Guillermo Covas”Ruta Nacional 5 km 580AnguilLa PampaCC116326Argentina

Beneﬁcial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease *** addition,a wide array of rhizospheric microbes are responsible for producing metabolically active compounds including various types of plant growth ***,microbial biodiversity studies could contribute to the improvement of agricultural practices in deprived areas,such as the Pampean semiarid *** vast majority of studies conducted on endophytic microorganisms have focused on intensive crop legume *** contrast,little attention has been paid to microorganisms of native legumes,whose ecology is not directly affected by human *** this study,endophytic microorganisms isolated from root nodules of a selected native legume of the genus Rhynchosia were *** isolates were studied with a focus on their plant growth-pro-moting rhizobacteria(PGPR)*** the edaphic characteristics of the Pampean semiarid region,the isolates obtained were evaluated for their ability to grow under three salt stress conditions(50,100,and 200 mM NaCl)and four different pH values(6,7,8,and 9).Based on their PGPR activities,the selected strains were phylogenetically grouped using *** results showed great variability among the isolates in terms of the characteristics *** legumes manifested a wide endophytic variability and remarkable perfor-mance in PGPR *** conclude that they could be used as potential bioinoculants for legume cultivation,an excellent alternative to the use of chemical fertilizers that currently pollute the environment.

关键词： Native strains endophytes PGPR native legumes stress

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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Matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.Marquès L.Lancia P.Loiseau P.forestier-Colleoni M.tarisien E.Atukpor V.Bagnoud C.Brabetz f.Consoli J.Domange f.Hannachi P.Nicolaï M.salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GsI Helmholtzzentrum für schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA fusion and technologies for Nuclear safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[Marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CsA).the spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CsA.

关键词： acceleration hydrodynamic collision

the soft X-ray Imager(sXI)on the sMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： s.sembay A.L.Alme D.Agnolon t.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont t.Crawford J.P.Breuer t.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor t.Crawford N.Eaton C.feldman C.forsyth t.frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland s-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.jones t.Kennedy K.Koch-Mehrin s.Kögl s.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani s.Parsons P.Patel J.Pearson G.Peikert f.s.Porter t.Pouliantis B.H.Qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman s.sachdev A.samsonov M.soman D.sibeck s.smit J.søndergaard R.speight s.stavland M.steller tianRan sun J.thornhill W.thomas K.Ullaland B.Walsh D.Walton C.Wang s.Yang school of Physics and Astronomy University of LeicesterLeicesterLE17RHUK space Park Leicester University of LeicesterLeicesterLE17RHUK Mullard space science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for space science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace technology MadridSpain EstEC European Space Agency2201 AZ NoordwijkNetherlands state Key Laboratory of space Weather National Space Science CentreBeijing 100190China University of Applied sciences and Arts Northwestern switzerland CH-5210 WindischSwitzerland Koegl space GmbH CH-8157 DielsdorfSwitzerland space Acoustics GmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied sciences 8400 WinterhurSwitzerland Genov solutions N-5172 LoddefjordNorway stM Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NAsA/Goddard space flight Centre MD 20771USA Center for space Physics Boston UniversityBostonMA 02215USA Department of theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

the soft X-ray Imager(sXI)is part of the scientific payload of the solar wind Magnetosphere Ionosphere Link Explorer(sMILE)*** is a joint science mission between the European space Agency(EsA)and the Chinese Academy of sciences(CAs)and is due for launch in *** is a compact X-ray telescope with a wide field-of-view(fOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the sMILE *** is sensitive to the soft X-rays produced by the solar Wind Charge eXchange(sWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s *** provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field *** sensitivity of the sXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of sMILE will enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United states.

关键词： soft X-ray Imaging micropore optics large area CCD

first evidence for chiral wobbling of triaxial nuclei

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Nuclear science and techniques 2024年第7期35卷 4-7页

作者： s.frauendorf Department of Physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in fig.1 taste quite differently.

关键词： turns Chiral mirror

tribological behavior of lubricant-impregnated porous polyimide

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friction 2024年第4期12卷 711-725页

作者： Jinbang LI Ningning ZHOU Janet s.s.WONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life technology of Precise Rotation and transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication