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Communications in Computational Physics 2016年第6期20卷 23-59页

作者： Alberto Sartori Antonio Cammi Lelio Luzzi Gianluigi Rozza Politecnico di Milano–Department of Energy CeSNEFEnrico Fermi Center for Nuclear Studiesvia La Masa 3420156MilanoItaly SISSA International School for Advanced StudiesMathematics Area–mathLabVia Bonomea 26534136 TriesteItaly.

In this work,two approaches,based on the certified Reduced Basis method,have been developed for simulating the movement of nuclear reactor control rods,in time-dependent non-coercive settings featuring a 3D geometrical *** particular,in a first approach,a piece-wise affine transformation based on subdomains division has been implemented for modelling the movement of one control *** the second approach,a“staircase”strategy has been adopted for simulating themovement of all the three rods featured by the nuclear reactor chosen as case *** neutron kinetics has been modelled according to the so-called multi-group neutron diffusion,which,in the present case,is a set of ten coupled parametrized parabolic equations(two energy groups for the neutron flux,and eight for the precursors).Both the reduced order models,developed according to the two approaches,provided a very good accuracy comparedwith high-fidelity results,assumed as“truth”*** the same time,the computational speed-up in the Online phase,with respect to the fine“truth”finite element discretization,achievable by both the proposed approaches is at least of three orders of magnitude,allowing a real-time simulation of the rod movement and control.

关键词： Reduced basis method control rod movement spatial kinetics parametrized geometry multi-group neutron diffusion non-coercive operators

Chip-based squeezing at a telecom wavelength

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Photonics Research 2019年第7期7卷 10-13页

作者： F.Mondain T.Lunghi A.Zavatta E.Gouzien F.Doutre M.De Micheli S.Tanzilli V.D'Auria Universite Cote d'Azur CNRSInstitut de Physique de NiceParc Valrose06108 Nice Cedex 2France Istituto Nazionale di Ottica (INO-CNR) Largo enrico Fermi 6 50125 FirenzeItaly LENS and Department of Physics Universita di Firenze50019 Sesto FiorentinoFirenzeItaly

We demonstrate a squeezing experiment exploiting the association of integrated optics and telecom technology as key features for compact, stable, and practical continuous variable quantum optics. In our setup, squeezed light is generated by single-pass spontaneous parametric down conversion on a lithium niobate photonic circuit and detected by a homodyne detector whose interferometric part is directly integrated on the same platform. The remaining parts of the experiment are implemented using commercial plug-and-play devices based on guided-wave technologies. We measure, for a CW pump power of 40 mW, a squeezing level of -2.00±0.05 dB (anti-squeezing 2.80 ±0.05 dB), thus confirming the validity of our approach and opening the way toward miniaturized and easy-to-handle continuous variable-based quantum systems.

关键词： squeezing association single-pass

LHCb观测到的J/ψJ/ψ峰:纯粲四夸克态?

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Science Bulletin 2020年第23期65卷 1954-1955页

作者： Jean-Marc Richard Institut de Physique des 2 Infinis IN2P3&UniversitéClaude Bernard4 rue Enrico Fermi69622 VilleurbanneFrance

Since several decades, a particular attention has been devoted to hadrons with anomalous properties [1–5]. On the experimental side, the search has been very difficult and disappointing. For instance, in the early 60’s, there has been some claims for baryon resonances with strangeness S=+1, the so-called Z baryons, while the established baryons have either S=0 or S < 0. But the Z spectrum was based on somewhat hazardous analyses of K+-nucleon scattering data without spin observables, and it faded away. It reappeared under the name of θ pentaquark, but it was never firmly established.

关键词： devoted instance observable

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神秘的新型重奇异Z_(cs)态

Science Bulletin 2021年第20期66卷 2045-2046页

作者： Marek Karliner Jonathan L.Rosner School of Physics and Astronomy Tel Aviv UniversityTel Aviv 69978Israel enrico Fermi Institute and Department of Physics University of ChicagoChicago IL 60637USA

For nearly forty years after the advent of the quark model [1,2],the only observed hadrons were mesons consistent with being a quark-antiquark(qq) pair and baryons consistent with being composed of three quarks(qqq). There was no reason why more ‘‘exotic" configurations, such as qqqq(tetraquarks) or qqqqq(pentaquarks), could not exist. Indeed, such a possibility was mentioned in the pioneering papers [1,2] and they had been predicted by such schemes as s–t channel duality in baryon-antibaryon scattering [3], the bag model of quark confinement [4–6], and binding of hadrons into molecules [7,8].

关键词： quark 1,2 mentioned

Oxidation in Ca/K-1144 iron-based superconductors polycrystalline compounds

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Superconductivity 2023年第4期8卷 9-17页

作者： Zuhawn Sung Anastasiya Duchenko Giuseppe Celentano Jaeyel Lee Xiaobing Hu Nicola Pompeo Francesca Varsano Andrea Masi Fermi National Accelerator Laboratory BataviaIL 60510USA Universitàdegli Studi Roma Tre Dipartimento di Ingegneria IndustrialeElettronica e MeccanicaVia Vito Volterra 6200146 RomaItaly ENEA C.R.FrascatiVia Enrico Fermi 4500044 FrascatiItaly Department of Materials Science and Engineering Northwestern UniversityEvanstonIL 60208USA The NUANCE Center Northwestern UniversityIL 60208USA ENEA C.R.CasacciaVia Anguillarese 30100123 RomaItaly

Iron‐based superconductors(IBSCs)are a class of material under investigation for the development of superconducting wires in the low‐temperature‐high magnetic fields power *** the various families of IBSCs,the 1144 CaKFe_(4)As_(4) compound is a promising material able to achieve outstanding superconducting properties with a cheap and simple chemical ***,in these compounds,is considered an obstacle for high intergranular critical current density,J_(c,GB).A study devoted to the evaluation of oxidation phenomena and their effects on the superconducting properties is thus needed in order to fully understand the involved *** the evaluation of polycrystalline samples obtained by a mechanochemically assisted synthesis route,a degradation of the critical temperature and critical currents has been observed concurrently with oxygen accumulation at grain boundaries in open ***,the crystalline structure at an atomic level seems not affected,as well as intragranular superconducting properties assessed by means of calorimetric *** results suggest that loss of superconducting properties in Ca/K‐1144 compounds following oxidation is significantly associated with the worsening of grain connectivity.

关键词： Grain boundaries Superconductivity Oxidation Microstructure Iron based superconductors

Ultra-broadband all-OPCPA petawatt facility fully based on LBO

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High Power Laser Science and Engineering 2020年第4期8卷 1-16页

作者： Mario Galletti Pedro Oliveira Marco Galimberti Munadi Ahmad Giedre Archipovaite Nicola Booth Emerald Dilworth Andy Frackiewicz Trevor Winstone Ian Musgrave Cristina Hernandez-Gomez GoLP/Instituto de Plasmas e Fusao Nuclear Instituto Superior TecnicoUniversidade de Lisboa1049-001 LisboaPortugal Central Laser Facility Science and Technology Facilities CouncilRutherford Appleton LaboratoryHarwell Science and Innovation CampusDidcotUK INFN-LNF Via Enrico Fermi 5400044 FrascatiItaly School of Engineering and Physical Sciences Heriot-Watt UniversityEdinburghUK

A petawatt facility fully based on noncollinear optical parametric chirped pulse amplification(NOPCPA)technology,Vulcan OPPEL(Vulcan OPCPA PEtawatt Laser),is *** system will be coupled with the existing hybridCPA/OPCPA VULCAN laser system(500 J,500 fs beamline;250 J,ns regime beamline)based on Nd:glass *** pulse duration(20 times shorter)combined with the system design will allow the auxiliary beamline and its secondary sources to be used as probe beams for longer pulses and their interactions with *** newly designed system will be mainly dedicated to electron beam generation,but could also be used to perform a variety of particle acceleration and optical radiation detection experimental *** this communication,we present the entire beamline design discussing the technology choices and the design supported by extensive simulations for each system ***,we present experimental results and details of our commissioned NOPCPA picosecond front end,delivering 1.5 mJ,~180 nm(1/e^(2))of bandwidth compressed to sub-15 fs.

关键词： high-power laser LBO nonlinear crystal nonlinear optics ultra-broadband OPA ultrafast laser

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重置意大利VG HOUSE改造

室内设计与装修 2018年第8期 124-127页

作者： coco arch.enrico scaramellini

VG HOUSE始建于20世纪20年代到30年代之间，其侧坐立一栋20世纪70年代建筑，场地环境呈现出不太和谐的画面。它与相邻的建筑格格不入，与周围的环境完全不一致。原建筑拥有一个朝南的立面，其余侧面均与四周环境隔离，呈现出封闭的立面... 详细信息

VG HOUSE始建于20世纪20年代到30年代之间，其侧坐立一栋20世纪70年代建筑，场地环境呈现出不太和谐的画面。它与相邻的建筑格格不入，与周围的环境完全不一致。原建筑拥有一个朝南的立面，其余侧面均与四周环境隔离，呈现出封闭的立面形态。

关键词： HOUSE 意大利场地环境年代建筑

Blockchain-as-a-Service and Blockchain-as-a-Partner: Implementation options for supply chain optimization

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Blockchain(Research and Applications) 2023年第2期4卷 12-27页

作者： Paolo Bottoni Claudio Di Ciccio Remo Pareschi Domenico Tortola Nicola Gessa Gilda Massa Department of Computer Science Sapienza University of RomeViale Regina Elena295Rome00161RMItaly Stake Lab University of MoliseC.da Fonte LapponePesche86090ISItaly Department of Bioscience and Territory University of MoliseC.da Fonte LapponePesche86090ISItaly TERIN-SEN-CROSS ENEA-Agenzia nazionale per le nuove tecnologiel'energia e lo sviluppo economico sostenibileVia Martiri di Monte Sole 4Bologna40129BOItaly e TERIN-SEN-CROSSENEA-Agenzia nazionale per le nuove tecnologiel'energia lo sviluppo economico sostenibile Piazzale Enrico Fermi 1Portici80055NAItaly

Smart contracts show a high potential to make supply chain management strategies epochally leap towards higher levels of productivity,not only in the functioning of production processes but also in terms of product innovation and overall economic *** article illustrates the principle of Income Sharing as a highly performing economic strategy for supply chains with a natural implementation in blockchain smart *** proposes a blockchain-based architecture that uses smart contracts to implement various algorithmic versions of the Income Sharing principle among companies participating in a supply *** formation of the total income and its consequent redistribution are calculated taking into account the role of the technological platform automating these procedures,which therefore becomes a party to the inter-company business project of a supply chain in the alternative roles,as feasible in business practice,of Blockchain-as-a-Service and *** approach is implemented on Hyperledger Fabric,the most widespread platform for private and consortium *** compare and justify this design choice with the alternative given by public blockchains,with specific attention to Ethereum.

关键词： Supply chain management Decentralized autonomous organization Income sharing Smart contract Distributed ledger Hyperledger fabric

Sintering and mechanical properties of β-SiC powder obtained from waste tires

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Journal of Advanced Ceramics 2016年第1期5卷 40-46页

作者： G.MAGNANI S.GALVAGNO G.SICO S.PORTOFINO C.FREDA E.BURRESI ENEA SSPT-PROMAS-TEMAF Faenza Research Laboratories Via Ravegnana 186 48018 Faenza(RA) Italy ENEA SSPT-PROMAS-NANO Portici Research Center P.le Enrico Fermi 1 80055 Portici(NA) Italy ENEA SSPT-PROMAS-MATAS Brindisi Research Center S.S.7 Appia km 70600 72100 Brindisi Italy

Plasma synthesized SiC powder obtained from quartz and carbonaceous residue of waste tires was successfully sintered at 1925 ℃ by pressureless liquid-phase method using yttria and alumina as sintering aids (T-SiC). Comparison with sintered SiC obtained from commercial powder (C-SiC) put in evidence of similar sintered density (98%T.D.), but much finer microstructure of T-SiC than that of C-SiC. T-SiC also showed higher flexural strength than C-SiC both at room temperature (508 vs. 458 MPa) and at 1500 ℃ (280 vs. 171 MPa). Difference in liquid phase was responsible for the differences in hardness and fracture toughness. The high value of the Young’s modulus of T-SiC (427 MPa) confirmed the high degree of sinterability of this powder and that it can be a promising candidate for structural applications with high added value.

关键词： sintering mechanical properties SiC structural application

Efficient bright γ-ray vortex emission from a laser-illuminated light-fan-in-channel target

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High Power Laser Science and Engineering 2021年第3期9卷 68-78页

作者： Hao Zhang Jie Zhao Yanting Hu Qianni Li Yu Lu Yue Cao Debin Zou Zhengming Sheng Francesco Pegoraro Paul McKenna Fuqiu Shao Tongpu Yu Department of Physics National University of Defense TechnologyChangsha 410073China SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUK Collaborative Innovation Center of IFSA(CICIFSA) Key Laboratory for Laser Plasmas(MoE)and School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute Shanghai 200240China Department of Physics enrico Fermi University of Pisaand CNR/INOPisa 56122Italy

X/γ-rays have many potential applications in laboratory astrophysics and particle *** several methods have been proposed for generating electron,positron,and X/γ-photon beams with angular momentum(AM),the generation of ultra-intense brilliant γ-rays is still ***,we present an all-optical scheme to generate a high-energy γ-photon beam with large beam angular momentum(BAM),small divergence,and high *** the first stage,a circularly polarized laser pulse with intensity of 10^(22) W/cm^(2) irradiates a micro-channel target,drags out electrons from the channel wall,and accelerates them to high energies via the longitudinal electric *** the process,the laser transfers its spin angular momentum(SAM)to the electrons’orbital angular momentum(OAM).In the second stage,the drive pulse is reflected by the attached fan-foil and a vortex laser pulse is thus *** the third stage,the energetic electrons collide head-on with the reflected vortex pulse and transfer their AM to the γ-photons via nonlinear Compton ***-dimensional particle-in-cell simulations show that the peak brilliance of the γ-ray beam is∼10^(22) photons·s^(-1)·mm^(-2)·mrad^(-2) per 0.1% bandwidth at 1 MeV with a peak instantaneous power of 25 TW and averaged BAM of 10^(6)h/*** AM conversion efficiency from laser to the γ-photons is unprecedentedly 0.67%.

关键词： laser-plasma interaction γ-rays