189,805 research outputs found
Turrietta-Giovannini Wedding Portrait, 1944
No full textWedding photo of Nettie Turrietta and Pietro Giovannini taken on their wedding day, August 23rd, 1944 at Albuquerque�s Immaculate Conception Catholic Church. Giovannini was an immigrant from Lucca, Italy. (Photo courtesy of Margaret Giovannini Tudor Staehlin.
Introduzione
No full textIntroduzione al fascicolo "Sulle Marche", curato da P. Giovannini e R. Giulianell
Pietro Giovannini, ca. 1925
No full textPietro Giovannini, an immigrant from Lucca, came to the United States in March of 1912. In Albuquerque he found a job in the Santa Fe Railroad shops on South First Street. Like many other Italian immigrants, Giovannini saved money in order to go into business for himself. Eventually he and Pete Giannini opened the White House Grocery at 201 South First Street. (Photo Courtesy of Margaret Giovannini Tudor Staehlin.
Grande guerra: oppositori e vittime
No full textIl fascicolo è dedicato a importanti questioni dell’Italia nella prima guerra mondiale, conflitto che – come noto – costituisce il tornante fondamentale della storia del ‘900, una drastica cesura che segna la fine del “lungo ‘800” e l’inizio del “secolo breve”, marcandolo in maniera indelebile.
Bruna Bianchi incentra il suo contributo sul pacifismo radicale; Paolo Giovannini esamina come la scienza neuropsichiatrica nazionale fronteggia il preoccupante fenomeno della simulazione di follia; Luca Gorgolini delinea le drammatiche vicende del trasferimento dei prigionieri austro-ungarici dalla Serbia all’Italia; Daniele Ceschin, infine, si sofferma sulle diverse configurazioni della morte nel periodo bellico
LINEE GUIDA PER LA MARCATURA DEI DOCUMENTI NORMATIVI SECONDO GLI STANDARD NORMEINRETE
No full textLe presenti Linee guida sono state elaborate dal Gruppo di lavoro dell’Agenzia per l’Italia digitale per l’evoluzione degli standard per la marcatura dei documenti normativi che ha operato a partire dal 2008 nell’ambito del progetto IRE-Sud. Il Gruppo di lavoro è diretto dalla Dott.ssa Maria Pia Giovannini, dirigente dell’Agenzia e responsabile dell’Area regole standard e guide tecniche.
Al Gruppo di lavoro hanno partecipato, oltre all’Agenzia per l’Italia
digitale1, che ha coordinato la redazione del documento, i principali centri di ricerca nazionali nel settore dell’informatica giuridica:
• Dipartimento di scienze dell'informazione dell'Università degli
Studi di Bologna;
• Centro Interdipartimentale di ricerca in Storia del diritto,
Filosofia e Sociologia del diritto e Informatica Giuridica
(CIRSFID) dell'Università degli Studi di Bologna;
• Istituto di Teoria e Tecniche dell’Informazione Giuridica
(ITTIG) del CNR;
• Istituto di informatica e telematica (IIT) del CNR
Metamaterial description of perpendicularly magnetized 2D antidot lattices - Presentazione poster
No full textA metamaterial description of collective modes in 2D antidot lattice (ADLs) perpendicularly magnetized has been performed. ADLs are composed of circular nanoholes of diameter d = 200 nm embedded into a CoFeB film having thickness of 41 nm. The analysis of collective modes has been carried out by means of a micromagnetic method, named Dynamical Matrix Method (DMM). The mode propagation is studied placing an external magnetic field H along the z-axis and the Bloch wave vector K is parallel to the x-axis. The aim of this study is to describe in terms of effective properties the spin dynamics in perpendicularly magnetized ADLs [1] by extending the simple rules on the effective wavelength and on the effective wave vector that were found for in-plane magnetized ADLs and their dependence on the corresponding Bloch quantities [2,3]. From the inspection of spatial profiles of collective modes it is possible to identify a characteristic wavelength which is commensurable with the periodicity a of the system. [1] P. Malagò et al., “Effective properties of perpendicularly magnetized 2D antidot lattices” in preparation
[2] R. Zivieri and L. Giovannini Metamaterials 6 (2012) e126
[3] R. Zivieri and L. Giovannini Photon. Nanostruct: Fundam. Appl. 11 (2013) 19
Stopping field for collective spin waves at the edge of magnetization reversal
No full textSimilarly to other magnetic systems, even magnonic crystals are characterized by soft modes with a vanishing frequency at the critical field of any given magnetic transition. The profile of these modes has a symmetry that depends on the symmetry change between the initial and final magnetic configurations[1]. The knowledge of the soft mode is not a theoretical-only issue, but can have technological implications, especially in the field of magnonic- and spin-logic devices, where collective spin waves are used for information storage and delivery[2]. Actually, it has been recently demonstrated[3] that the bandwidth of the mode that softens at the critical field, undergoes dramatic variations even when just approaching this critical field. This fact can result either in a band broadening of modes usually non-dispersive (like some end modes), or, vice versa, in a strong band reduction for modes with usually a large bandwidth (as the fundamental mode). In some cases, it is possible to design the magnonic crystal to be characterized by one or another soft mode with the desired symmetry in order to use its bandwidth variation close to the transition field for a specific purpose. We apply this concept to a rectangular array of interacting elliptical dots of Permalloy (i.e., a 2-D magnonic crystal), magnetized along the major axis, and, by calculations with the dynamical matrix method, find out the behavior of the soft mode dispersion at the edge of magnetization reversal. We discuss the correlation among different curves characterizing the magnetic system close to reversal: the magnetization curve, the soft mode frequency vs. field curve, and the frequency vs. wavevector curve. We investigate different aspect ratios for the ellipses, and different magnetic configurations. We show how the soft mode is characterized by a bandwidth that goes to zero at a magnetic field quite distinct from the critical transition field, and we call this field stopping field, because at this field the collective soft mode turns into non-dispersive (stationary). We believe that this feature can be used to design versatile devices, in which information can be stored or delivered at the energy costs of a small magnetic field variation.
[1] F. Montoncello, L. Giovannini, F. Nizzoli, P. Vavassori, and M. Grimsditch, Phys. Rev. B 77, 214402 (2008).
[2] A. V. Chumak, V. I. Vasyuchka, A. A. Serga, M. P. Kostylev, V. S. Tiberkevich, and B. Hillebrands, Phys. Rev. Lett. 108, 257207 (2012). [3] F. Montoncello and L. Giovannini, Applied Physics Letters 104, 242407 (2014)
Spin waves in configurational antiferromagnetic states: transitions to and from ferromagnetic states
No full textWe study collective spin waves in transversally magnetized chains of thin elliptical dots initially arranged into an antiferromagnetic (AF) configuration. The dispersion relations of the SW as well as the corresponding magnetization precession profiles (eigenvectors) are computed with the dynamical matrix method [1]. We report the peculiar features of AF optical and acoustical spin modes within the effective wavevector model [2], which has been adapted to the present geometry. We investigate the effects of the application of a transverse external field, leading
the system from a perfect AF configuration to the ferromagnetic (FM) state, at a specific transition field. We discuss the mode localization and symmetry, and in particular, we focus on the AF soft mode, its symmetry and its relationship with the instability leading to AF-to-FM transition. We discuss the importance and potential application of the SW propagative properties suddenly changed at the switching from AF to FM. Finally, we present the calculations of spin dynamics concerning a FM-to-AF transition in a chain of ellipses with different width: in this case, the different shape anisotropy of the two ellipses results in different switching fields and hence in a field interval where the AF state is spontaneously attained. We show how this AF field interval can also be tuned by an effective uniaxial anisotropy of one out of two ellipses: this is indicative of any other source of anisotropy (like inverse-magnetostriction, particularly promising for voltage driven magnetic transitions in multiferroics): in this way, we investigate the AF-to-FM transition spin dynamics by varying the effective anisotropy constant of the material. Finally, we show and comment on thepeculiar and remarkable change of slope of the mode dispersion across the AF-to-FM transition, with its implications in the field of magnon-spintronics devices.
References: [1] L. Giovannini, F. Montoncello, and F. Nizzoli, Phys. Rev. B 75, 024416 (2007).
[2] F. Montoncello, S. Tacchi, L. Giovannini, M. Madami, G. Gubbiotti, G. Carlotti, E. Sirotkin, E. Ahmad, F. Y. Ogrin, and V. V. Kruglyak, Appl. Phys. Lett. 102, 202411 (2013)
Effective yet reliable computation of hyperfine coupling constants in solution by a QM/MM approach: Interplay between electrostatics and non-electrostatic effects
No full textIn this paper, we have extended to the calculation of hyperfine coupling constants, the model recently proposed by some of the present authors [Giovannini et al., J. Chem. Theory Comput. 13, 4854-4870 (2017)] to include Pauli repulsion and dispersion effects in Quantum Mechanical/Molecular Mechanics (QM/MM) approaches. The peculiarity of the proposed approach stands in the fact that repulsion/dispersion contributions are explicitly introduced in the QM Hamiltonian. Therefore, such terms not only enter the evaluation of energetic properties but also propagate to molecular properties and spectra. A novel parametrization of the electrostatic fluctuating charge force field has been developed, thus allowing a quantitative reproduction of reference QM interaction energies. Such a parametrization has been then tested against the prediction of EPR parameters of prototypical nitroxide radicals in aqueous solutions
Regolazione del lavoro e lavori senza regole: il caso italiano
No full textIl capitolo intende concentrare l'attenzione sulle trasformazioni del lavoro nel contesto italiano alla luce dei forti cambiamenti che hanno investito lo scenario europeo. Il focus è sulle tipologie, sulla struttura occupazionale e sui mutamenti che si registrano nella sfera lavorativa e professionale. Vengono altresì analizzati gli effetti sulla composizione sociale e sulle condizioni di lavoro con un chiaro riferimento alle logiche e alle strategie seguite dagli attori sociali. Infine, non mancano considerazioni specifiche sulla trasformazione del rapporto tra tempi di vita e tempi di lavoro sperimentata dai soggetti coinvolti
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