Francesco Botticini (1446 - 1497) "dipintore da Firenze"

La tesi che sto scrivendo, a conclusione del corso di Laurea Magistrale in SAVS (Storia della Arti Visive, dello Spettacolo e dei Nuovi Media), tratta di Francesco Botticini, artista fiorentino della fine del Quattrocento. La mia dissertazione sarà suddivisa in cinque capitoli, nei quali si affronteranno aspetti diversi del personaggio in questione. Il primo capitolo servirà da introduzione e sarà valutata la fortuna critica del pittore, con particolare attenzione a quella dell'ultimo secolo. Nel secondo sarà presentato Francesco Botticini attraverso l'esposizione della sua biografia e l'elenco delle opere a lui attribuite secondo un ordine cronologico. Lo scopo di questo capitolo è soltanto quello di far conoscenza con un artista quasi sconosciuto, senza rivelare troppi dettagli. Il terzo tratterà delle maggiori influenze artistiche riscontrabili nei dipinti del Botticini. Dopo una breve contestualizzazione storica e un veloce resoconto sulla polivalenza e l'interdipendenza delle botteghe fiorentine del Quattrocento, si passerà all'analisi di alcuni pittori, i quali furono determinanti nell'evoluzione stilistica del Botticini. Dei vari artisti verranno indicati, in maniera sintetica, accenni biografici e tratti distintivi, per poi arrivare al confronto delle opere (tra le loro e quelle del Botticini). Il quarto capitolo sarà costituito da schede di lettura dell'opera d'arte. Analizzerò i dipinti che ritengo più importanti all'interno della sua carriera artistica: in ognuna di esse avrò la possibilità di approfondire tutti i fattori, artistici e non, che interagirono tra di sé per la realizzazione finale dell'opera. L'ultimo capitolo sarà la conclusione dell'intera tesi, nella quale cercherò di mostrare la figura del Botticini nel suo complesso, basandomi su quanto discusso in precedenza. Ovviamente l'introduzione sarà preceduta da un indice e da una premessa, mentre la conclusione sarà seguita dalle immagini del corpus di opere citate (del Botticini e degli altri artisti) e dalla bibliografia

A MATLAB script and a methodology for the powertrain design of a fuel cells-battery hybrid electric supercar

The urgency to decarbonize the transportation sector covers all kinds of vehicles, here included highperformance competition vehicles. Among the technologies able to guarantee zero emissions during the use phase, fuel cells (FCs) and energy storage systems (ESS), e.g. batteries, offer a great and still largely underexplored potential for complementary and synergic use in hybrid powertrains. Vehicles based on such technologies are cells-battery hybrid electric vehicles (FCHEV), and a niche of these are electric supercars (FCHES). In this context, the degrees of freedom of hybrid powertrains design and the different requirements of FCs and batteries frame the highly complex task of defining a clear and objective methodology to identify an optimal ratio among FC-battery power sources, whose lack jeopardizes a rigorous decision process as well as a general consensus and leads to the acceptance of sub-optimal solutions. In this study an energy/power-based methodology is developed in MATLAB environment considering the longitudinal vehicle dynamics of a typical high-performance parallel FCHES, using telemetry data from a real racetrack as common target for all the evaluated powertrain candidates and using realistic mass values. Under the constraint of equal performance (i.e., equal lap time), several FC-battery parallel hybrid powertrains are numerically evaluated with varying relative energy, power, weight, and under different regenerative braking levels. The set of obtained results allows to draw an objective rightsizing on the FC-battery power share and on the required energy capacity for a parallel FCHEV, as well as mass, hydrogen consumption, etc. The presented methodology offers a general use workflow applicable to any category of vehicles, supporting the engineering of hybrid FC-battery high-performance propulsion systems. The developed code will be made available upon request under the FAIR (Findable, Accessible, Interoperable, Reusable) guidelines

Evolution of the interfacial structure of LaAlO3 on SrTiO3

The evolution of the atomic structure of LaAlO3 grown on SrTiO3 was investigated using surface x-ray diffraction in conjunction with model-independent, phase-retrieval algorithms between two and five monolayers film thickness. A depolarizing buckling is observed between cation and oxygen positions in response to the electric field of polar LaAlO3, which decreases with increasing film thickness. We explain this in terms of competition between elastic strain energy, electrostatic energy, and electronic reconstructions. The findings are qualitatively reproduced by density-functional theory calculations. Significant cationic intermixing across the interface extends approximately three monolayers for all film thicknesses. The interfaces of films thinner than four monolayers therefore extend to the surface, which might affect conductivity

Unit cell of graphene on Ru(0001): a 25 x 25 supercell with 1250 carbon atoms

The structure of a single layer of graphene on Ru(0001) has been studied using surface x-ray diffraction. A surprising superstructure has been determined, whereby 25 x 25 graphene unit cells lie on 23 x 23 unit cells of Ru. Each supercell contains 2 x 2 crystallographically inequivalent subcells caused by corrugation. Strong intensity oscillations in the superstructure rods demonstrate that the Ru substrate is also significantly corrugated down to several monolayers, and that the bonding between graphene and Ru is strong and cannot be caused by van der Waals bonds. Charge transfer from the Ru substrate to the graphene expands and weakens the C-C bonds, which helps accommodate the in-plane tensile stress. The elucidation of this superstructure provides important information in the potential application of graphene as a template for nanocluster arrays.Comment: 9 pages, 3 figures, paper submitted to peer reviewed journa

Electronic and Geometric Corrugation of Periodically Rippled, Self-nanostructured Graphene Epitaxially Grown on Ru(0001)

Graphene epitaxially grown on Ru(0001) displays a remarkably ordered pattern of hills and valleys in Scanning Tunneling Microscopy (STM) images. To which extent the observed "ripples" are structural or electronic in origin have been much disputed recently. A combination of ultrahigh resolution STM images and Helium Atom diffraction data shows that i) the graphene lattice is rotated with respect to the lattice of Ru and ii) the structural corrugation as determined from He diffraction is substantially smaller (0.015 nm) than predicted (0.15 nm) or reported from X-Ray Diffraction or Low Energy Electron Diffraction. The electronic corrugation, on the contrary, is strong enough to invert the contrast between hills and valleys above +2.6 V as new, spatially localized electronic states enter the energy window of the STM. The large electronic corrugation results in a nanostructured periodic landscape of electron and holes pockets.Comment: 16 pages, 6 figure

Structure and properties of chemically prepared nanographene islands characterized by scanning tunneling microscopy

Single layer graphene islands with a typical diameter of several nanometers were grown on a Pt (111) substrate. Scanning tunneling microscopy (STM) analysis showed most of islands are hexagonally shaped and the zigzag-type edge predominates over the armchair-type edge. The apparent height at the atoms on the zigzag edge is enhanced with respect to the inside atoms for a small sample bias voltage, while such an enhancement was not observed at the atoms on the armchair edge. This result provides an experimental evidence of spatially (at the zigzag edge) and energetically (at the Fermi level) localized edge state in the nanographene islands, which were prepared chemically on Pt (111).Comment: 8 pages, 8 figures, 1 tabl

Study of the stability of the 5-aminolevulinic acid tyrosine ester in aqueous solution

Photodynamic therapy based on photoactivable porphyrins (PAPs) can treat various dermatological conditions. The side-effects as well as the non-selective or insufficient accumulation of PAPs in the targeted tissues limit performances. We studied the stability in solution at different temperatures (21 degrees C; 4 degrees C), different pH values (7.5; 2.0), and as a function of time of 5-aminolevulinic acid's Tyrosine-ester, a molecule presenting interesting properties to selectively produce PAPs in blood vessels after topical application. Solutions of this precursor can be kept up to 24 h at refrigerated temperatures and under acidic pH. At room temperature or physiological pH, they must be prepared minutes before their use

Sexual and functional outcomes of prostate artery embolisation. A prospective long-term follow-up, large cohort study.

Among minimally invasive procedures for treating benign prostate hyperplasia (BPH) prostate artery embolisation (PAE) is described as safe and effective. Aim of this study is to report our results, focusing on sexual outcomes (erectile and ejaculatory functions sparing) of PAE in patients suffering from bladder outlet obstruction (BOO) secondary to BPH

Kinetics and thermodynamics of carbon segregation and graphene growth on Ru(0001)

We measure the concentration of carbon adatoms on the Ru(0001) surface that are in equilibrium with C atoms in the crystal's bulk by monitoring the electron reflectivity of the surface while imaging. During cooling from high temperature, C atoms segregate to the Ru surface, causing graphene islands to nucleate. Using low-energy electron microscopy (LEEM), we measure the growth rate of individual graphene islands and, simultaneously, the local concentration of C adatoms on the surface. We find that graphene growth is fed by the supersaturated, two-dimensional gas of C adatoms rather than by direct exchange between the bulk C and the graphene. At long times, the rate at which C diffuses from the bulk to the surface controls the graphene growth rate. The competition among C in three states - dissolved in Ru, as an adatom, and in graphene - is quantified and discussed. The adatom segregation enthalpy determined by applying the simple Langmuir-McLean model to the temperature-dependent equilibrium concentration seriously disagrees with the value calculated from first-principles. This discrepancy suggests that the assumption in the model of non-interacting C is not valid