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Radioisotope production using lasers:From basic science to applications

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Matter and Radiation at Extremes 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.Molloy D.Raffestin M.Alonzo G.G.Rapisarda D.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.McNamee M.La Cognata S.Palmerini T.Carriere M.Cipriani G.Di Giorgio G.Cristofari R.de Angelis G.A.P.Cirrone D.Margarone 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 Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia School of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom Dipartimento di fisica e Astronomia“E.Majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly Dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly Dipartimento di fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di fisica Nucleare Sezione di PerugiaPerugiaItaly ELI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain Dipartimento fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,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 *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Inconsistencies in four-dimensional Einstein-Gauss-Bonnet gravity

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Chinese Physics C 2021年第1期45卷 89-96页

作者： Julio Arrechea Adria delhom Alejandro Jimenez-Cano Instituto de Astrofisica de Andalucia(IAA-CSIC) Glorieta de la AstronomiaGranadaSpain departamento de fisica teorica and IFIC Centro Mixto Universidad de Valencia-CSIC.Universidad de ValenciaBuijassot-46100ValenciaSpain departamento de fisica teorica y del Cosmos and CAFPE Universidad de Granada18071 GranadaSpain

We attempt to clarify several aspects concemi ng the recently presented four-dimensional Ein stein-Gauss-Bonnet *** argue that the limiting procedure outlined in[***.124,081301(2020)]generally involves ill-defined terms in the four dimensional field *** ways to circumvent this issue are discussed,alongside remarks regarding specific solutions of the *** prove that,although linear perturbations are well behaved around maximally symmetric backgrounds,the equations for second-order perturbations are illdefined even around a Minkowskia n *** on ally,we perform a detailed analysis of the spherically symmetric solutions and find that the central curvature singularity can be reached within a finite proper time.

关键词： alternative theories of gravity singularities Einstein・Gauss-Bonnet

Comments on "Non-existence of Shilnikov chaos in continuous-time systems"

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Applied Mathematics and Mechanics(English Edition) 2013年第9期34卷 1175-1176页

作者： A.ALGABA F.FERNANdeZ-SANCHEZ M.MERINO A.J.RODRIGUEZ-LUIS departamento de Matematicas Centro de Investigacion de Fisica Teorica y Matematica FIMATUniversity of Huelva departamento de Matematica Aplicada II E.S.IngenierosUniversity of Sevilla Camino de los Descubrimientos s/n

A paper, ＂Non-existence of Shilnikov chaos in continuous-time systems＂ was published in the journal Applied Mathematics and Mechanics （English Edition）. The authors gave sufficient conditions for the non-existence of homoclinic and heteroclinic orbits in an nth-order autonomous system. Unfortunately, we show in this comment that the proof presented is erroneous and the result is invalid. We also provide two counterexamples of the wrong criterion stated by the authors.

关键词： homoclinic chaos heteroclinic chaos non-existence of Shilnikov chaos

Why static bound-state calculations of tetraquarks should be met with scepticism

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Chinese Physics C 2017年第5期41卷 49-53页

作者： George Rupp Eef van Beveren centro de fisica e Engenharia de Materiais Avancados Instituto Superior Tecnico Universidade de Lisboa P-1049-001 Lisboa Portugal centro de fisica da UC Departamento de Fisica Universidade de Coimbra P-3004-516 Coimbra Portugal

Recent experimental signals have led to a revival of tetraquarks,the hypothetical q~2q~2 hadronic states proposed by Jaffe in 1976 to explain the light scalar *** structures with exotic quantum numbers have indeed been observed recently,though a controversy persists as to whether these are true resonances and not merely kinematical threshold enhancements,or otherwise states not of a true q~2q~2 ***,puzzling non-exotic mesons are also often claimed to have a tetraquark ***,the corresponding model calculations are practically always carried out in pure and static bound-state approaches,ignoring completely the coupling to asymptotic two-meson states and unitarity,especially the dynamical effects *** this short paper we argue that these static predictions of real tetraquark masses are highly unreliable and provide little evidence of the very existence of such states.

关键词： meson scalar quark dynamical asymptotic otherwise argue merely decay exotic

The Cauchy Problem for Coupled Nonlinear Schrdinger Equations with Linear Damping： Local and Global Existence and Blowup of Solutions

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Chinese Annals of Mathematics,Series B 2016年第5期37卷 665-682页

作者： Joao-Paulo DIAS Mario FIGUEIRA Vladimir V. KONOTOP LCMAF-CIO Faculdade de Ciencias Universidade de Lisboa Av. Prof. Gama Pinto 2 1649-003 Lisboa Portugal. centro de fisica teorica e Computacional and departamento de fisica Faculdade de Ciencias Universidade de Lisboa Campo Grande Ed.C8 1749-016 Lisboa Portugal.

The authors study, by applying and extending the methods developed by Cazenave(2003), Dias and Figueira(2014), Dias et al.(2014), Glassey(1994–1997), Kato(1987), Ohta and Todorova(2009) and Tsutsumi(1984), the Cauchy problem for a damped coupled system of nonlinear Schrdinger equations and they obtain new results on the local and global existence of H^1-strong solutions and on their possible blowup in the supercritical case and in a special situation, in the critical or supercritical cases.

关键词： supercritical Cauchy applying estimates proof admissible constants uniqueness nonlinearity inequality

Photoconductive devices for terahertz pulsed spectroscopy:a review[Invited]

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Photonics Research 2016年第3期4卷 36-42页

作者： E.Castro-Camus M.Alfaro centro de Investigaciones en Optica A.C. departamento de Matematicas y fisica Centro de Ciencias BasicasUniversidad Autonoma de Aguascalientes

Photoconductive switches were the key components that allowed the generation and detection of coherent broadband electromagnetic pulses at terahertz frequencies, opening the possibility for performing spectroscopy and,therefore, measuring complex dielectric properties of materials in this band, which was mostly unexplored. In this paper, we present a brief introduction to the operation principles of these devices. Subsequently, we present a review of the current state-of-the-art in this field and discuss the challenges to be faced in future development of these devices.

关键词： As Ga THz Photoconductive devices for terahertz pulsed spectroscopy:a review[Invited

Synthesis and spectroscopic investigations of trivalent europium- doped Z_(2)Si_(3)O_(8)(Z = Mg, Ca and Sr) nanophosphors for display applications

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Rare Metals 2021年第9期40卷 2610-2617页

作者： Suman Sheoran Kuldeep Singh Vijeta Tanwar Sitender Singh Anura Samantilleke devender Singh department of Chemistry Maharshi Dayanand UniversityRohtak 124001India centro de fisica Universidade of MinhoBraga 4710057Portugal

To explore the silicate lattice-based nanophosphors, a series of Eu3+-doped Z_(2)Si_(3)O_(8)(Z = Mg, Ca and Sr) materials were prepared by sol–gel procedure. The metal nitrates and silica powder were used as precursor components for the synthesis of these luminescent materials. Photoluminescence(PL) emission spectra, powder X-ray diffraction(PXRD), energy-dispersive X-ray spectroscopy(EDS), Fourier transform infrared spectroscopy(FTIR) and transmission electron microscopy(TEM)spectroscopic techniques were applied for the characterization of the fabricated materials. Three peaks were observed at 589, 613 and 650–652 nm corresponding to ^(5)D_(0)→^(7)F_(1-3) transition in PL emission spectra. Upon395 nm excitation and at 0.03 mol Eu3+, these nanophosphors displayed optimum photoluminescence with the most intense peak analogous to ^(5)D_(0)→^(7)F_(2)transition of dopant ion. The as-prepared phosphor materials were re-heated at1050 and 1150 ℃ to observe the consequences of higher temperatures on the emission intensity and crystal *** analysis confirmed that all the synthesized materials were of crystalline nature, and the crystallinity was observed to be improved by increasing the temperature. In the FTIR spectrum, peaks at 483 and 610 cm^(-1) proved the existence of SiO_(4)group in Ca_(2)Si_(3)O_(8), and the peak centered at 417 cm^(-1) confirmed the presence of MgO6 octahedral in Mg_(2)Si_(3)O_(8) materials. TEM images were used to determine the particle size(13–35 nm) and to study the threedimensional structure of nanophosphor materials. The experimental studies indicate that these materials may be promising as red-emitting nanophosphors for white lightemitting diodes.

关键词： Z_(2)Si_(3)O_(8) Nanophosphors Sol–gel Photoluminescence Crystalline

Quantitative Electrophilicity Measures

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物理化学学报 2018年第6期34卷 662-674页

作者： GONZáLEZ Marco Martínez CáRdeNAS Carlos RODRíGUEZ Juan I. LIU Shubin HEIDAR-ZAdeH Farnaz MIRANDA-QUINTANA Ramón Alain AYERS Paul W. Laboratory of Computational and Theoretical Chemistry Faculty of Chemistry University of Havana Havana 10400 Cuba. departamento de Quimica and Centro de Quimica Universidade de Coimbra 3004-535 Coimbra Portugal. departamento de fisica Fac

Quantitative correlation of several theoretical electrophilicity measures over different families of organic compounds are examined relative to the experimental values of Mayr et ***,the ability to predict these values accurately will help to elucidate the reactivity and selectivity trends observed in charge-transfer reactions.A crucial advantage of this theoretical approach is that itprovides this information without the need of experiments,which are often demanding and ***,two different types of electrophilicity measures were ***,models derived from conceptual density functional theory(c-DFT),including Parr's original proposal and further generalizations of this index,are *** instance,the approaches of Gázquez et *** Chamorro et *** considered,whereby it is possible to distinguish between processes in which a molecule gains or loses ***,we also explored two novel electrophilicity *** one hand,the potential of environmental perturbations to affect electron incorporation into a system is analyzed in terms of recent developments in *** studies highlight the importance of considering the molecular surroundings when a consistent description of chemical reactivity is *** the other hand,we test a new definition of electrophilicity that is free from inconsistencies(so-called thermodynamic electrophilicity).This approach is based on Parr's pioneering insights,though it corrects issues present in the standard working expression for the calculation of ***,we use machine-learning tools(i.e.,symbolic regression) to identify the models that best fit the experimental *** this way,the best possible description of the electrophilicity values in terms of different electronic structure quantities is ***,this straightforward approach enables one to obtain good correlations between the theoretical and experimental quantities by using the simple,yet p

关键词： Electrophilicity Conceptual density functional theory Symbolic regression Genetic programming Grammatical evolution

Nucleon Finite Volume Effect and Nuclear Matter Properties in a Relativistic Mean-Field Theory

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Communications in Theoretical Physics 2006年第6X期46卷 1052-1058页

作者： R. Costa A.J. Santiago H. Rodrigues J. Sa Borges Instituto de fisica Universidade do Estado do Rio de Janeiro Rio de Janeiro-RJ 20559-900 Brazil centro Federal de Educ~ao Tecnológica Rio de Janeiro Brazil

Effects of excluded volume of nucleons on nuclear matter are studied, and the nuclear properties that follow from different relativistic mean-field model parametrizations are compared. We show that, for all tested parametrizations, the resulting volume energy al and the symmetry energy J are around the acceptable values of 16 MeV and 30 MeV, and the density symmetry L is around 100 MeV. On the other hand, models that consider only linear terms lead to incompressibility Ko much higher than expected. For most parameter sets there exists a critical point （pc, δc）, where the minimum and the maximum of the equation of state are coincident and the incompressibility equals zero. This critical point depends on the excluded volume parameter r. If this parameter is larger than 0.5 fm, there is no critical point and the pure neutron matter is predicted to be bound. The maximum value for neutron star mass is 1.85M⊙, which is in agreement with the mass of the heaviest observed neutron star 4U0900-40 and corresponds to r = 0.72 fm. We also show that the light neutron star mass （1.2M⊙） is obtained for r ≌ 0.9 fro.

关键词： nuclear matter relativistic models nuclear matter aspects of neutron stars