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A new method of discriminating different types of post-Archean ophiolitic basalts and their tectonic significance using Th-Nb and Ce-Dy-Yb systematics

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geoscience Frontiers 2015年第4期6卷 481-501页

作者： Emilio Saccani dipartimento di fisica e Scienze della Terra Università di Ferrara

In this paper, a new discrimination diagram using absolute measures of Th and Nb is applied to postArchean ophiolites to best discriminate a large number of different ophiolitic basalts. This diagram was obtained using 〉2000 known ophiolitic basalts and was tested using -560 modern rocks from known tectonic settings. Ten different basaltic varieties from worldwide ophiolitic complexes have been examined. They include two basaltic types that have never been considered before, which are：（1） medium-Ti basalts （MTB） generated at nascent forearc settings; （2） a type of mid-ocean ridge basalts showing garnet signature （g-MORB） that characterizes Alpine-type （i,e., non volcanic） rifted margins and ocean-continent transition zones （OCTZ）. In the Th-Nb diagram, basalts generated in oceanic subductionunrelated settings, rifted margins, and OCTZ can be distinguished from subduction-related basalts with a misclassification rate 〈 1%. This diagram highlights the chemical variation of oceanic, rifted margin, and OCTZ basalts from depleted compositions to progressively more enriched compositions reflecting, in turn, the variance of source composition and degree of melting within the MORB-OIB array. It also highlights the chemical contributions of enriched （OIB-type） components to mantle sources. Enrichment of Th relative to Nb is particularly effective for highlighting crustal input via subduction or crustal contamination. Basalts formed at continental margin arcs and island arc with a complex polygenetic crust can be distinguished from those generated in intra-oceanic arcs in supra-subducrion zones （SSZ） with a misclassification rate 〈1%. Within the SSZ group, two sub-settings can be recognized with a misclassification rate 〈0.5%. They are：（1） SSZ influenced by chemical contribution from subduction- derived components （forearc and intra-arc sub-settings） characterized by island arc tholeiitic （IAT） and boninitic basalts; （2） SSZ with no contribution from subduction-derived comp

关键词： Basalts Ophiolite discrimination diagram Trace elements Plate tectonics

Cosmology with Two Compactification Scales

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Chinese Physics Letters 2000年第4期17卷 310-312页

作者： A.g.Agnese M.La Camera dipartimento di fisica delPUniversita di genova Istituto Nazionale di Fisica NucleareSezione di Genova Via Dodecaneso 3316146 GenovaItaly

We consider a(4+d)-dimensional spacetime broken up into a(4-n)-dimensional Minkowski spacetime(where n goes from 1 to 3)and a compact(n+d)-dimensional *** the present time the n compactification radii are of the order... 详细信息

关键词： manifold. length. Minkowski

Plasmon hybridization engineering in self-organized anisotropic metasurfaces

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Nano Research 2018年第7期11卷 3943-3956页

作者： Maria C. giordano Stefano Longhi Matteo Barelli Andrea Mazzanti Francesco Buatier de Mongeot giuseppe Della Valle dipartimento di fisica Universita di Genova Via Dodecaneso 33 Genova I-16146 Italy dipartimento di fisica and IFN-CNR Politecnico di Milano Piazza L. da Vinci 32 Milano 1-20133 Italy

The engineering of self-organized plasmonic metasurfaces is demonstrated using a maskless technique with defocused ion-beam sputtering and kinetically controlled deposition. The proposed reliable, cost-effective, and controllable approach enables large-area （order of square centimeter） sub-wavelength periodic patterning with close-packed gold nanostrips. A multi-level variant of the method leads to high-resolution manufacturing of vertically stacked nanostrip dimer arrays, without resorting to lithographic approaches. The design of these self-organized metasurfaces is optimized by employing plasmon hybridization methods. In particular, preliminary results on the so-called gap-plasmon configuration of the nanostrip dimers, implementing magnetic dipole resonance in the near-infrared range, are reported. This resonance offers a superior sensitivity and field enhancement, compared with the more conventional electric dipole resonance. The translational invariance of the nanostrip configuration leads to a high filling factor of the hot spots. These advanced features make the large-area metasurface based on gap-plasmon nanostrip dimers very attractive for surface-enhanced linear and nonlinear spectroscopy （e.g., surface-enhanced Raman scattering） and plasmon-enhanced photon harvesting in solar and photovoltaic cells.

关键词： metasurfaces self-organization gold nanostructures plasmon hybridization gap plasmon resonances

Detailed Analysis of Quantum Phase Transitions Within the u(2) Algebra

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Communications in Theoretical Physics 2010年第10期54卷 589-593页

作者： L.Fortunato L.Sartori dipartimento di fisica“g.galilei”and INFN the ECT Europen Center for Theoretical Nuclear Physics CISAS g.Colombo

We analyze in detail the quantum phase transitions that arise in models based on the u(2) algebraicdescription for bosonic systems with two types of scalar *** we discuss the quantum phase transition thatoccurs in hamiltonians that admix the two dynamical symmetry chains u(2)  u(1) and u(2)  so(2) by diagonalizingthe problem exactly in the u(1) *** we apply the coherent state formalism to determine the energy *** we show that a quantum phase transition of a different nature, but displaying similar characteristics, may arisealso within a single chain just by including higher order terms in the hamiltonian.

关键词： algebraic models Lie algebra quantum phase transitions Lipkin model

Status and accuracy of the Monte Carlo generators for luminosity measurements

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Chinese Physics C 2010年第6期34卷 883-888页

作者： g.Montagna g.Balossini C.Bignamini C.M.Carloni Calame O.Nicrosini F.Piccinini dipartimento di fisica Nucleare e Teorica Università di Pavia Istituto Nazionale di fisica Nucleare School of Physics & Astronomy University of Southampton

The status and accuracy of the precision Monte Carlo generators used for luminosity measurements at flavour factories is reviewed. It is shown that, thanks to a considerable, long-term effort in tuned comparisons between the predictions of independent programs, as well as in the validation of the generators against the presently available calculations of the next-to-next-to-leading order QED corrections to Bhabha scattering, the theoretical accuracy reached by the most precise tools is of about one per mille. This error estimate is valid for realistic experimental cuts, appears to be quite robust and is already sufficient for very accurate luminosity measurements. However, recent progress and possible advances to further improve it are also discussed.

关键词： Luminosity QED Bhabha scattering radiative corrections Monte Carlo NNLO calculations

Large-area flexible nanostripe electrodes featuring plasmon hybridization engineering

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Nano Research 2021年第3期14卷 858-867页

作者： Carlo Mennucci Debasree Chowdhury giacomo Manzato Matteo Barelli Roberto Chittofrati Christian Martella Francesco Buatier de Mongeot dipartimento di fisica Universitàdegli Studi di Genovavia Dodecaneso 33I-16146GenovaItaly

Multifunctional flexible Au electrodes based on one-dimensional(1D)arrays of plasmonic gratings are nanofabricated over large areas with an engineered variant of laser interference lithography optimized for low-cost transparent *** nanostripe(NS)arrays achieve sheet resistance in the order of 20 Ohm/square on large areas(∼cm^(2))and are characterized by a strong and dichroic plasmonic response which can be easily tuned across the visible(VIS)to near-infrared(NIR)spectral range by tailoring their cross-sectional *** vertically a second nanostripe,separated by a nanometer scale dielectric gap,we form near-field coupled Au/SiO_(2)/Au dimers which feature hybridization of their localized plasmon resonances,strong local field-enhancements and a redshift of the resonance towards the NIR *** possibility to combine excellent transport properties and optical transparency on the same plasmonic metasurface template is appealing in applications where low-energy photon management is mandatory like e.g.,in plasmon enhanced spectroscopies or in photon harvesting for ultrathin photovoltaic *** remarkable lateral order of the plasmonic NS gratings provides an additional degree of freedom for tailoring the optical response of the multifunctional electrodes via the excitation of surface lattice resonances,a Fano-like coupling between the broad localised plasmonic resonances and the collective sharp Rayleigh modes.

关键词： nanofabrication nanostripes transparent electrodes plasmonic dimers interference lithography surface lattice resonances

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

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

Non-equilibrium Statistic Features in dissipative Heavy Ion Collision ^(27)Al+ ^(27)Al

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Chinese Physics Letters 1999年第12期16卷 876-878页

作者： WANg Qi LI Song-lin TIAN Wen-dong HU Peng-yun LU Jun F.Amorini M.Cabibb g.Cardellas P.Figuere A.Musumarra M.Papa g.pappalardo F.Rizzo S.Romano S.Tudisco B.Heusch Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 Istituto Nazionale di fisica Nucleare the Laboratorio Nazionale del SudItaly Istituto Nazionale di fisica Nuclearr SezCataniaItaly dipartimento di fisica University Catania Italy Centre de Recherches Nucleaires StrasbourgFrance

The excitation functions of dissipative products have been measured in the reaction 27Al+27Al at incident energies from 114 to 127MeV in steps of 200keV. Detection angles vary continuously from 10.4° to 57.4° in laboratory system. An angular coherent width more than 40° in center of mass is obtained. The results from the analysis of excitation functions with nonself-averaging are characterized by a quasi-periodic long-range energy structure embedded in the disorder Ericson fluctuation.

关键词： excitation equilibrium steps