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Experimental measurements of gamma-photon production and estimation of electron/positron production on the PETAL laser facility

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Matter and Radiation at Extremes 2024年第5期9卷 32-47页

作者： F.Brun L.Ribotte G.Boutoux X.Davoine P.E.Masson-Laborde Y.Sentoku n.Iwata n.blanchot D.Batani I.Lantuéjoul L.Lecherbourg B.Rosse C.Rousseaux B.Vauzour D.Raffestin E.D’Humières X.Ribeyre Centre Lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CEA DAMCESTAF-33116 Le BarpFrance CEA DAMDIFF-91297 ArpajonFrance CEA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine Laser(PETAL)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SESAME(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SPECTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the PETAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process. positron hypothesis

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numerical investigation of spallation neutrons generated from petawatt-scale laser-driven proton beams

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Matter and Radiation at Extremes 2022年第2期7卷 8-17页

作者： B.Martinez S.n.Chen S.Bolaños n.blanchot G.Boutoux W.Cayzac C.Courtois X.Davoine A.Duval V.Horny I.Lantuejoul L.Le Deroff P.E.Masson-Laborde G.Sary B.Vauzour R.Smets L.Gremillet J.Fuchs LULI-CnRS CEAUPMC Univ Paris 06:Sorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance CEA DAMDIFF-91297 ArpajonFrance Horia Hulubei national Institute of Physics and nuclear Engineering Bucharest-MagureleRomania CEA DAMCESTAF-33114 Le BarpFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChâtelFrance LPP Sorbonne UniversitéCNRSEcole PolytechniqueF-91128 Palaiseau CedexFrance

Laser-driven neutron sources could offer a promising alternative to those based on conventional accelerator technologies in delivering compact beams of high brightness and short *** examine this through particle-in-cell and Monte Carlo simulations that model,respectively,the laser acceleration of protons from thin-foil targets and their subsequent conversion into neutrons in secondary lead *** parameters relevant to the 0.5 PW LMJ-PETAL and 0.6–6 PW Apollon systems are *** to its high intensity,the 20-fs-duration 0.6 PW Apollon laser is expected to accelerate protons up to above 100MeV,thereby unlocking efficient neutron generation via spallation *** a result,despite a 30-fold lower pulse energy than the LMJ-PETAL laser,the 0.6 PW Apollon laser should perform comparably well both in terms of neutron yield and ***,we predict that very compact neutron pulses,of∼10 ps duration and∼100μm spot size,can be released provided the lead convertor target is thin enough(∼100μm).These sources are characterized by extreme fluxes,of the order of 10^(23) n cm^(−2) s^(−1),and even ten times higher when using the 6 PW Apollon *** values surpass those currently achievable at large-scale accelerator-based neutron sources(∼10^(16) n cm^(−2) s^(−1)),or reported from previous laser experiments using low-Z converters(∼10^(18) n cm^(−2) s^(−1)).By showing that such laser systems can produce neutron pulses significantly brighter than existing sources,our findings open a path toward attractive novel applications,such as flash neutron radiography and laboratory studies of heavy-ion nucleosynthesis.

关键词： thereby attractive extreme

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Enhanced ion acceleration using the high-energy petawatt PETAL laser

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Matter and Radiation at Extremes 2021年第5期6卷 62-79页

作者： D.Raffestin L.Lecherbourg I.Lantúejoul B.Vauzour P.E.Masson-Laborde X.Davoine n.blanchot J.L.Dubois X.Vaisseau E.d’Humières L.Gremillet A.Duval Ch.Reverdin B.Rosse G.Boutoux J.E.Ducret Ch.Rousseaux V.Tikhonchuk D.Batani CEA DAMCESTAF-33116 Le BarpFrance Centre Laser Intenses et Applications Universit´e de Bordeaux-CNRS-CEAUMR 510733405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Universit´e Paris-Saclay CEALMCE91680 Bruy`eres-le-ChˆatelFrance CEA DRFIRFUGANILF-14000 CaenFrance ELI-Beamlines Research Centre 25241 DolníBrezanyCzech Republic

The high-energy petawatt PETAL laser system was commissioned at CEA’s Laser M´egajoule facility during the 2017–2018 *** paper reports in detail on the first experimental results obtained at PETAL on energetic particle and photon generation from solid foil targets,with special emphasis on proton *** a moderately relativistic(ntensity,proton energies as high as 51 MeV have been measured significantly above those expected from preliminary numerical simulations using idealized interaction *** hydrodynamic and kinetic simulations,taking into account the actual laser parameters,show the importance of the energetic electron production in the extended low-density preplasma created by the laser *** hot-electron generation occurs through two main pathways:(i)stimulated backscattering of the incoming laser light,triggering stochastic electron heating in the resulting counterpropagating laser beams;(ii)laser filamentation,leading to local intensifications of the laser field and plasma channeling,both of which tend to boost the electron ***,owing to the large(∼100μm)waist and picosecond duration of the PETAL beam,the hot electrons can sustain a high electrostatic field at the target rear side for an extended period,thus enabling efficient target normal sheath acceleration of the rear-side *** particle distributions predicted by our numerical simulations are consistent with the measurements.

关键词： acceleration high energy

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Langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug nanosensor Application

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1311-1318页

作者： WOnG Yeong Yi F L Supian A Radzwan M Musa n F n Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHnS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor

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Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 891-910页

作者： n.D.nGUYEn T.n.nGUYEn Faculty of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City 71309Viet Nam Faculty of Engineering and Technology Kien Giang UniversityChau Thanh 92000Viet Nam

This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam *** analyses include three models for porosity distribution and two scenarios for thermal *** material properties are assessed under two conditions,i.e.,temperature dependence and temperature *** theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order *** governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev *** simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam *** findings highlight the significant influence of temperature-dependent(TD)material properties on metal foam beams'buckling and vibration responses.

关键词： Ritz method Chebyshev function buckling vibration metal foam beam higher-order beam theory(HOBT)

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Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology

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China Foundry 2024年第1期21卷 60-70页

作者： İsmail Cem Akgün Çağın Bolat Ali Gökşenli Faculty of Mechanical Engineering Istanbul Technical University34437İstanbulTurkey Faculty of Engineering Samsun University55420SamsunTurkey

In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and *** this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a *** to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors *** this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).Micro evaluations(optical and FESEM)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF ***,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive *** results show that PEC particles can be an alternative to expensive hollow spheres used in the previous ***,a favorable relationship is ascertained between the aging treatment and mechanical properties such as compression strength and plateau strength.

关键词： die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation

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Towards defining soil quality of Mediterranean calcareous agricultural soils:Reference values and potential core indicator set

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International Soil and Water Conservation Research 2024年第1期12卷 145-155页

作者： Germán A.Durán Daniel Sacristán Edelweis Farrús Jaume Vadell Institut de Recerca i FormacióAgrària i Pesquera de les Illes Balears C/Eusebi Estada14507009PalmaSpain Plant Biology Department University of Valencia46100BurjassotValenciaSpain Soil and Environmental Quality Department Centro de Investigaciones sobre Desertificación-CIDE(CSIC-Universitat de València-Generalitat Valenciana)Carretera Moncada-Náquera km 4.546113MoncadaValenciaSpain Universitat de les Illes Balears Cra.De Valldemossakm 7507122PalmaSpain

To avoid soil degradation,adapt to climate change and comply with the Sustainable Development goals 2030(Un General Assembly),establishing the quality/fertility of the agricultural soils of the Mediterranean region and evaluate how these evolve with time is *** enables adequate management practices to be *** Mediterranean calcareous region has received little attention in this sense,in spite its soil ***,24 different representative calcareous agricultural soils of the Mediterranean region,including the main management strategies of agricultural soils(rainfed and irrigated),were sampled from the island of Mallorca;and their physical,chemical and biological properties *** values obtained for most of the soil characteristics allowed to establish an initial approach to the reference values for the type of calcareous agricultural soils considered,and to clearly distinguish the effect of rainfed or irrigation management practices on soils properties and *** enzyme activities were not stimulated by the irrigation conditions assayed or they were only in dry conditions,suggesting optimum enzyme activities could be obtained when alternating dry and humid soil *** organic carbon,calcium carbonate and active lime revealed of significant importance in the collection of ***,the results obtained clearly indicate the heterogeneity of the region and its implications on the different soil ***,this study could serve as a starting point to adequately establish the quality(fertility)for Mediterranean calcareous agricultural soils and their reference values by conducting further research in this region and including more type of soils.

关键词： Soil fertility Mediterranean agricultural soils Calcareous soils Soil enzymes Soil management

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Weather influenced nestling growth of an insectivorous but not a granivorous grassland passerine in Argentina

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Avian Research 2024年第2期15卷 156-162页

作者： Martín Alejandro Colombo Adrian Jauregui Luciano n.Segura Laboratorio de Ecología de Aves.Institute“Dr.Raúl A.Ringuelet”(ILPLA)-UnLP/COnICET Boulevard 1201437La PlataB1900Buenos AiresArgentina

nestling growth of birds can be affected by weather *** general,it is expected that higher temper-atures favor growth by improving food availability and nestling metabolism,while rain hinders it by reducing foraging ***,most of these patterns have been described in insectivorous cavity-nesting birds in temperate *** tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to *** measured nestlings of the Hellmayr’s Pipit(Anthus hellmayri,an insectivorous passerine)and the Grassland Yellow-Finch(Sicalis luteola,which feeds its nestlings exclusively with seeds)during three breeding seasons(2017-2020)in central-eastern *** took measurements of tarsus and body mass,modeled growth curves using nonlinear mixed-effects models,and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to *** pipits(60 nestlings from 21 nests),minimum temperatures during the growth period were positively associated with tarsus and body mass ***,there was a positive association between precipitation during the pre-hatching period and tarsus ***,none of the weather variables analyzed had significant effects on nestling growth of finches(131 nestlings from 35 nests).Dietary contrast between species may explain the different *** activity and abundance can be affected by weather variations within the span of a breeding season,whereas seeds may depend on conditions from previous years,making the effects harder to *** with reduced asymptotic size can have reduced chances of ***,pipit populations could be impacted if they experience cold and dry conditions during their breeding season,which is of major relevance in the current context of climate change.

关键词： Finches Grassland birds neotropical birds Pipits Precipitation Temperature

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Marinoan glaciation in the Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeography 2024年第2期13卷 293-308页

作者： H.n.Bhattacharya Department of Earth Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of the Pokaran Boulder Bed,representing the most basal unit of the neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on the detrital and inherited zircon population of the Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryochron of the Cryogenian Period is envisaged for the Pokaran Boulder *** well-preserved Ediacaran elements in the post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of the Marwar *** glacial deposition at the base of the Marwar Supergroup strengthens the regional correlation between the studied sediments with the Lesser Himalayan Blaini-Krol-Tal sediments and the Haqf Supergroup of *** available zircon ages and paleomagnetic data of the Malani Igneous suite,along with the Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of the Marwar Supergroup add significant information to the neoproterozoic Earth history.

关键词： neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

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5-Bromo-2'-deoxyuridine labeling:historical perspectives,factors infiuencing the detection,toxicity,and its implications in the neurogenesis

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neural Regeneration Research 2024年第2期19卷 302-308页

作者： Joaquín Martí-Clúa Unidad de Citología e Histología.Departament de Biologia Cel·lular de Fisiologia i d’Immunologia.Facultad de Biociencias.Institut de Neurociències.Universidad Autónoma de Barcelona08193 BellaterraBarcelonaSpain

The halopyrimidine 5-bromo-2′-deoxyuridine(BrdU)is an exogenous marker of DnA *** the introduction of monoclonal antibodies against BrdU,an increasing number of methodologies have been used for the immunodetection of this synthesized bromine-tagged base analogue into replicating *** labeling is widely used for identifying neuron precursors and following their fate during the embryonic,perinatal,and adult neurogenesis in a variety of vertebrate species including birds,reptiles,and *** to BrdU toxicity,its incorporation into replicating DnA presents adverse consequences on the generation,survival,and settled patterns of *** may lead to false results and misinterpretation in the identification of proliferative *** this review,I will indicate the detrimental effects of this nucleoside during the development of the central nervous system,as well as the reliability of BrdU labeling to detect proliferating ***,it will show factors influencing BrdU immunodetection and the contribution of this nucleoside to the study of prenatal,perinatal,and adult *** adult neurogenesis will also be *** is my hope that this review serves as a reference for those researchers who focused on detecting cells that are in the synthetic phase of the cell cycle.

关键词： 5-bromo-2′-deoxyuridine adult neurogenesis human adult neurogenesis labeling pitfalls prenatal neurogenesis proliferation S-phase suturing S-phase toxicity

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