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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

Primordial black hole mass functions as a probe of cosmic origin

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： Yi-Fu Cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce *** standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from *** demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic ***,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

The W3C Data Catalog Vocabulary,Version 2:Rationale,Design Principles,and Uptake

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Data Intelligence 2024年第2期6卷 457-487页

作者： Riccardo Albertoni David Browning Simon Cox Alejandra N.Gonzalez-Beltran Andrea Perego Peter Winstanley Istituto di Matematica Applicata e Tecnologie Informatiche"enrico Magenes" Consiglio Nazionale delle Ricerche(IMATI-CNR)GenoaItaly Independent Consultant United Kingdom LandandWater CSiROMelbourneAustralia Scientific Computing Rutherford Appleton LaboratoryScience and Technology Facilities CouncilHarwell Cam-pusOx110QXUnited Kingdom European Parliament Luxembourg Semantic Arts Fort CollinsCO80524USA

DCAT is an RDF vocabulary designed to facilitate interoperability between data catalogs published on the *** its first release in 2014 as a W3C Recommendation,DCAT has seen a wide adoption across communities and domains,particularly in conjunction with implementing the FAIR data principles(forfindable,accessible,interoperable and reusable data).These implementation experiences,besides demonstrating the fitness of DCAT to meet its intended purpose,helped identify existing issues and ***,over the last few years,additional requirements emerged in data catalogs,given the increasing practice of documenting not only datasets but also data services and *** paper illustrates the new version of DCAT,explaining the rationale behind its main revisions and extensions,based on the collected use cases and requirements,and outlines the issues yet to be addressed in future versions of DCAT.

关键词： Data Catalogs Interoperability Discoverability FAIR data

Recent advances concerning polyurethane in leather applications:an overview of conventional and greener solutions

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Collagen and Leather 2023年第1期5卷 1-15页

作者： Jize Liu Federica Recupido Giuseppe Cesare Lama Maria Oliviero Letizia Verdolotti Marino Lavorgna Institute for Polymers Composites and Biomaterials(IPCB-CNR)Piazzale Enrico Fermi 180055 Portici(Naples)Italy

Leather is one of the most popular products across globe and holds a significant place in the economy,while the pollution,associated to traditional leather industry,is far away on the"green chemistry"*** this sense,polyurethanes,which exhibit tunable chemical structures by selecting suitable precursors,can fit specific requirements,and the developments of green strategies make them important candidates for leather *** mini review briefly outlines the recent development of conventional(petrol-based)and sustainable polyurethanes in the leather industry,including their design and properties,in applications such as synthetic leather and surface-finishing(coatings/binders).Finally,outlooks of the future tendency,including more environmental-friendly strategies,bio-sourced/recycled materials and development of high-value multifunctional leather materials,are also here proposed.

关键词： Conventional leather Artificial leather polyurethane-synthetic leather polyurethane-based binders polyurethane-based-materials Polyurethane-based-coatings

A new iron free treatment with oral fish cartilage polysaccharide for iron deficiency chronic anemia in inflammatory bowel diseases:A pilot study

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World Journal of Gastroenterology 2007年第10期13卷 1575-1578页

作者： Andrea Belluzzi Giulia roda Francesca Tonon Antonio Soleti Alessandra Caponi Anna Tuci Aldo roda enrico roda enrico roda Gastroenterology UnitUniversity of BolognaS.Orsola HospitalVia Massarenti

AIM:To investigate the effect of a new oral preparation,highly concentrated in fish cartilage,in a group of inflammatory bowel diseases(IBD)patients with chronic iron deficient ***:In an open label pilot study,we supple-mented a group of 25 patients(11 with Crohn's disease and 14 with ulcerative colitis)in stable clinical conditions and chronic anemia with a food supplement which does not contain iron but contains a standardized fraction of fish cartilage glycosaminoglycans and a mixture of antioxidants(Captafer Medestea,Turin,Italy).Patients received 500 mg,twice a day during meals,for at least 4 *** were suggested to maintain their alimentary *** time 0 and after 2 and 4 mo,emocrome,sideremia and ferritin were *** data were analyzed with Student's t ***:Three patients relapsed during the study(2 in the 3rd mo,1 in the 4th mo),two patients were lost to follow up and two patients dropped out(1 for orticaria,1 for gastric burning).Of the remaining 18 patients,levels of serum iron started to rapidly increase within the 2nd mo of treatment,P < 0.05),whereas serum ferritin and hemoglobin needed a longer period to significantly improve their serum levels(mo 4)P < *** product was safe,easy to administer and well tolerated by ***:These data suggest a potential new treatment for IBD patients with iron deficiency chronic anemia and warrant further larger controlled studies.

关键词：炎症性肠病缺铁性慢性贫血鱼类软骨多糖口服无铁制剂治疗

Large-scale photonic natural language processing

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Photonics Research 2022年第12期10卷 2846-2853页

作者： CARLO M.VALENSISE IVANA GRECCO DAVIDE PIERANGELI CLAUDIO C enrico Fermi Research Center(CREF) 00184 RomeItaly Physics Department Sapienza University of Rome00185 RomeItaly Institute for Complex Systems National Research Council(ISC-CNR)00185 RomeItaly

Modern machine-learning applications require huge artificial networks demanding computational power and ***-based platforms promise ultrafast and energy-efficient hardware,which may help realize nextgeneration data processing ***,current photonic networks are limited by the number of inputoutput nodes that can be processed in a single *** restricted network capacity prevents their application to relevant large-scale problems such as natural language ***,we realize a photonic processor for supervised learning with a capacity exceeding 1.5×10^(10)optical nodes,more than one order of magnitude larger than any previous implementation,which enables photonic large-scale text encoding and *** exploiting the full three-dimensional structure of the optical field propagating in free space,we overcome the interpolation threshold and reach the over-parameterized region of machine learning,a condition that allows high-performance sentiment analysis with a minimal fraction of training *** results provide a novel solution to scale up light-driven computing and open the route to photonic natural language processing.

关键词： demanding overcome exceeding

Ultracold atomic gases going strong

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National Science Review 2016年第2期3卷 168-170页

作者： Cheng Chin James Franck Institute Enrico Fermi InstituteUniversity of Chicago

The year 2015 marks the 20th anniversary of the achievement of Bose-Einstein condensation(BEC)in atomic *** BEC,realized by Eric Cornell,Carl Wieman and Wolfgang Ketterle in1995,commenced an exciting wave to explore quantum few-and many-body *** from solid state matter and helium superfluids,atomic condensates in the gas phase come with

关键词： body BEC Ultracold atomic gases going strong length

In-silico synthesis of lowest-pressure high-T_(c) ternary superhydrides

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npj Computational Materials 2022年第1期8卷 1119-1125页

作者： Roman Lucrezi Simone Di Cataldo Wolfgang von der Linden Lilia Boeri Christoph Heil Institute of Theoretical and Computational Physics Graz University of TechnologyNAWI Graz8010GrazAustria Dipartimento di Fisica Sapienza Universitàdi Roma00185RomeItaly enrico Fermi Research Center Via Panisperna 89 A00184RomeItaly

We report the theoretical prediction of two high-performing hydride superconductors BaSiH_(8)and SrSiH_(8).They are thermodynamically stable above pressures of 130 and 174 GPa,respectively,and metastable below *** anharmonic phonon calculations,we determine the minimum pressures of dynamical stability to be around 3 GPa for BaSiH8 and 27 GPa for SrSiH_(8),and using the fully anisotropic Migdal-Eliashberg theory,we predict Tc’s around 71 and 126 K,*** also introduce a method to estimate the lowest pressure of synthesis,based on the calculation of the enthalpy barriers protecting the BaSiH_(8)Fm3¯m structure from decomposition at various *** kinetic pressure threshold is sensibly higher than the one based on dynamic stability,but gives a much more rigorous limit for synthesizability.

关键词： synthesis stability high

First-principles search of hot superconductivity in La-X-H ternary hydrides

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npj Computational Materials 2022年第1期8卷 1-8页

作者： Simone Di Cataldo Wolfgang von der Linden Lilia Boeri Institute of Theoretical and Computational Physics Graz University of TechnologyNAWI Graz8010GrazAustria Dipartimento di Fisica Sapienza Universitàdi Roma00185RomaItaly Centro Ricerche enrico Fermi Via Panisperna89a00184RomaItaly

Motivated by the recent claim of hot superconductivity with critical temperatures up to 550 K in La + x hydrides,we investigate the high-pressure phase diagram of compounds that may have formed in the experiment,using first-principles calculations for evolutionary crystal structure prediction and *** from the hypothesis that the observed T_(c) may be realized by successive heating upon a pre-formed LaH_(10) phase,we examine plausible ternaries of lanthanum,hydrogen and other elements present in the diamond anvil cell: boron,nitrogen,carbon,platinum,gallium,*** find that only boron and,to a lesser extent,gallium form metastable superhydride-like structures that can host high-T_(c) superconductivity,but the predicted T_(c)’s are incompatible with the experimental *** results indicate that,while the claims of hot superconductivity should be reconsidered,it is very likely that unknown H-rich ternary or multinary phases containing lanthanum,hydrogen,and possibly boron or gallium may have formed under the reported experimental conditions,and that these may exhibit superconducting properties comparable,or even superior,to those of currently known hydrides.

关键词： hydrides boron superconductivity