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Two-flavor hybrid stars with the Dyson-Schwinger quark model

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Chinese Physics C 2017年第11期41卷 110-116页

作者：魏金标陈欢 H.-J.Schulze School of Mathematics and Physics China University of Geosciences INFN Sezione di Catania Dipartimento di FisicaUniversitá di Catania

We study the properties of two-flavor quark matter in the Dyson-Schwinger model and investigate the possible consequences for hybrid neutron stars,with particular regard to the two-solar-mass *** find that with some extreme values of the model parameters,the mass fraction of two-flavor quark matter in heavy neutron stars can be as high as 30 percent and the possible energy release during the conversion from nucleonic neutron stars to hybrid stars can reach 1052 erg.

关键词： hybrid stars quark matter equation of state Dyson-Schwinger equations

The Space and Time Features of Global SST Anomalies Studied by Complex Principal Component Analysis

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Advances in Atmospheric Sciences 1999年第1期16卷 3-23,5+9+11+15+17+19+21页

作者：骆美霞 dipartimento di fisica Generale Universita di Torino Turin Italy and Istituto di Cosmogeofisica del CNR Turin Italy

In this paper, the variability characteristics of the global field of sea surface temperature (SST) anomaly are studied by complex principal component (c.p.c.) analysis, whose results are also compared with those of real p.c. analysis. The data consist of 40 years of global SST monthly averages over latitudes from 42 5°S to 67 5°N. In the spatial domain, it is found that the distribution of the first complex loading amplitude is characterized by three areas of large values: the first one in the eastern and central equatorial Pacific Ocean, the second one in the northern tropical Indian Ocean and South China Sea, the third one in the northern Pacific Ocean. As it will be explained, this pattern may be considered as representative of El Nio mode. The first complex loading phase pattern shows a stationary wave in the Pacific (also revealed by real p.c. analysis) superimposed to an oscillating disturbance, propagating from the Pacific to Indian or the opposite way. A subsequent correlation analysis among different spatial points allows revealing disturbances actually propagating westward from the Pacific to the Indian Ocean, which could therefore represent reflected Rossby waves, i.e. the west phase of the signals that propagate disturbances of thermal structure in the tropical Pacific Ocean. In the time domain, a relation between the trend of the first complex principal component and the ENSO cycle is also established.

关键词： Global sea surface temperature anomalies ENSO Complex principal component analysis Travelling disturbances

Characterisation of Photocathodes Based on Pb Thin Film Deposited by UV Pulsed Laser Ablation

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Journal of Materials Science & Technology 2014年第1期30卷 37-40页

作者： Francisco Gontad Antonella Lorusso Giancarlo Gatti Massimo Ferrario Laura Gioia Passione Luana Persano Nicola Lovergine Alessio Perrone Istituto Nazionale di fisica Nucleare e Università del Salento Università del Salento Dipartimento di Matematica e Fisica "E.De Giorgi" Laboratori Nazionali di Frascati Istituto Nazionale di Fisica Nucleare Center for Biomolecular Nanotechnologies Istituto Italiano di Tecnologia dipartimento di Ingegneria dell'Innovazione Università del Salento National Nanotechnology Laboratory(NNL)

This work deals with the deposition of lead （Pb） thin films by the UV pulsed laser ablation technique, for their further use as photocathode devices in superconducting radio frequency guns. Scanning electron microscopy and atomic force microscopy analyses were performed to study the morphological features of Pb thin films deposited on Si （100） and Nb substrates. The films showed a granular structure with a nearly fully covered surface only for that one deposited on Nb substrate. X-ray diffraction measurements indicate the growth of polycrystalline Pb thin films with a preferential orientation along （111） planes. Results of the photoemission performance of Pb thin film deposited on Nb substrate showed a very encouraging average value of quantum efficiency of 6 x 10-5 through a single-photon absorption process, promoting further studies in the realisation of Pb photocathodes by this technique.

关键词： Pulsed laser deposition Lead thin film Metallic photocathodes Quantum efficiency

A Lattice Boltzmann Study of Phase Separation in Liquid-Vapor Systems with Gravity

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Communications in Computational Physics 2010年第2期7卷 350-361页

作者： Artur Cristea Giuseppe Gonnella Antonio Lamura Victor Sofonea Center for Fundamental and Advanced Technical Research Romanian AcademyBd.Mihai Viteazul 24300223 Timi¸soaraRomania dipartimento di fisica Universita di Bari and INFNSezione di BariVia Amendola 17370126 BariItaly Istituto Applicazioni Calcolo CNRVia Amendola 122/D70126 BariItaly

Phase separation of a two-dimensional van der Waals fluid subject to a grav-itational force is studied by numerical simulations based on lattice Boltzmann methodsimplemented with a finite difference scheme. A growth e... 详细信息

关键词： Lattice Boltzmann phase separation liquid-vapor gravity

Reaction mechanisms in massive nuclei collisions and perspectives for synthesis of heavier superheavy elements

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Nuclear Science and Techniques 2013年第5期24卷 98-106页

作者： GIARdiNA G NASIROV A K MANDAGLIO G CURCIARELLO F De LEO V FAZIO G ROMANIUK M dipartimento di fisica e di Scienze della Terra dell'Università di Messina Istituto Nazionale di fisica Nucleare Sezione di Catania Joint Institute for Nuclear Research Institute of Nuclear Physics Centro Siciliano di fisica Nucleare e Struttura della Materia Catania 95125Italy

We discuss a hardship in synthesis of heaviest super heavy elements in massive nuclei reactions due to the hindrance to complete fusion of reacting nuclei caused on the onset of quasifission process which strongly competes with complete fusion and due to the strong increase of fission yields along the de-excitation cascade of the compound nucleus in comparison with the evaporation residue *** hindrance to formation of compound nucleus and evaporation residue is determined by the characteristic of the entrance channel.

关键词：超重元素反应机制合成碰撞聚变反应残余物复合核核反应

Quantum cellular automata and free quantum field theory

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Frontiers of physics 2017年第1期12卷 65-75页

作者： Giacomo Mauro D'Ariano Paolo Perinottit QUIT Group Dipartimento di Fisica via Bassi 6 1-27100 Pavia Italy

In a series of recent papers [1-4] it has been shown how free quantum field theory can be derived without using mechanical primitives （including space-time, special relativity, quantization rules, etc.）, but only considering the easiest quantum algorithm encompassing a countable set of quantum systems whose network of interactions satisfies the simple principles of unitarity, homogeneity, locality, and isotropy. This has opened the route to extending the axiomatic information-theoretic derivation of the quantum theory of abstract systems [5, 6] to include quantum field theory. The inherent discrete nature of the informational axiomatization leads to an extension of quantum field theory to a quantum cellular automata theory, where the usual field theory is recovered in a regime where the discrete structure of the automata cannot be probed. A simple heuristic argument sets the scale of discreteness to the Planck scale, and the customary physical regime where discreteness is not visible is the relativistic one of small waveveetors. In this paper we provide a thorough derivation from principles that in the most general case the graph of the quantum cellular automaton is the Cayley graph of a finitely presented group, and showing how for the case corresponding to Euclidean emergent space （where the group resorts to an Abelian one） the automata leads to Weyl, dirac and Maxwell field dynamics in the relativistic limit. We conclude with some perspectives towards the more general scenario of non-linear automata for interacting quantum field theory.

关键词： quantum automata quantum walks quantum fields axiomatics Planck scale

SOME PRELIMINARY INFORMATION ON SYNdiOTACTIC POLYSTYRENE CATALYSTS

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Chinese Journal of Polymer Science 1988年第4期6卷 365-369页

作者： Adolfo Zambelli,Claudio Pellecchia,Leone Oliva,韩世敏 dipartimento di fisica Universita'di Salerno 84081 Baronissi (SA) Italy dipartimento di fisica Universita'di Salerno 84081 Baronissi (SA) Italy dipartimento di Chimica Universita'di Napoli Via Mezzocannone 4 Ⅰ-80134 Napoli Italy Institute of Chemistry Academia Sinica Beijing China

Syndiotactic specific polymerization of styrene has been investigated by13C NMR analysis and isotopic laelling methods. The value of the activation energy involved in the steric control has been determined. Some infor... 详细信息

关键词： We wish to thank prof. A. di Donato Universita’ di Napoli Italy for radioactivity measurements

Note on non-vacuum conformal family contributions to Rényi entropy in two-dimensional CFT

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Chinese Physics C 2017年第6期41卷 46-55页

作者：张甲举 dipartimento di fisica Universita degli Studi di Milano-Bicocca Piazza della Scienza 3 1-20126 Milano Italy

We calculate the contributions of a general non-vacuum conformal family to R′enyi entropy in twodimensional conformal field theory（CFT）. The primary operator of the conformal family can be either non-chiral or chiral, and we denote its scaling dimension by ？. For the case of two short intervals on a complex plane, we expand the R′enyi mutual information by the cross ratio x to order x^（2△＋2）. For the case of one interval on a torus with low temperature, we expand the R′enyi entropy by q = exp（-2πβ/L）, with β being the inverse temperature and L being the spatial period, to order q^（△＋2）. To make the result meaningful, we require that the scaling dimension ？ cannot be too small. For two intervals on a complex plane we need △ 〉 1, and for one interval on a torus we need △ 〉 *** work in the small Newton constant limit on the gravity side and so a large central charge limit on the CFT side,and find matches of gravity and CFT results.

关键词： Renyi entropy entanglement entropy conformal field theory

Confocal-based fluorescence fluctuation spectroscopy with a SPAD array detector

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Light(Science & Applications) 2021年第2期10卷 289-300页

作者： Eli Slenders Marco Castello Mauro Buttafava Federica Villa Alberto Tosi Luca Lanzanó Sami Valtteri Koho Giuseppe Vicidomini Molecular Microscopy and Spectroscopy Istituto Italiano di TecnologiaGenoaItaly dipartimento di Eiettronica Informazione e BioingegneriaPolitecmco di MilanoMilanItaly Nanoscopy and NIC@IIT lstituto Italiano di TecnologiaGenoaItaly dipartimento di fisica e Astronomia Universita di CataniaCataniaItaly

The combination of confocal laser-scanning microscopy(CLSM)and fluorescence fluctuation spectroscopy(FFS)is a powerful tool in studying fast,sub-resolution biomolecular processes in living cells.A detector array can further enhance CLSM-based FFS techniques,as it allows the simultaneous acquisition of several samples-essentially images-of the CLSM detection ***,the detector arrays that have previously been proposed for this purpose require tedious data corrections and preclude the combination of FFS with single-photon techniques,such as fluorescence lifetime ***,we solve these limitations by integrating a novel singie-photon-avalanche-diode(SPAD)array detector in a CLSM *** validate this new implementation on a series of FFS analyses:spot-variation fluorescence correlation spectroscopy,pair-correlation function analysis,and image-derived mean squared displacement *** predict that the unique combination of spatial and temporal information provided by our detector will make the proposed architecture the method of choice for CLSM-based FFS.

关键词： spectroscopy correction integrating