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Indagini isotopiche del carbonio su materia organica di successioni stratigrafiche al limite Retico/Hettangiano.
No full textAnalisi numerica di soluzioni innovative per il miglioramento delle prestazioni di accumuli termici latenti
No full textSi è ricercato un modello numerico che replicasse alcuni dati sperimentali a disposizione, riguardanti la fusione di un PCM all'interno di strutture periodiche porose 3D realizzate tramite additive manufacturing. Sono stati simulati 4 provini, uno vuoto, caso reference e 3 contenenti le strutture con diversa dimensione del poro di base, ma costante porosità. Si sono analizzati dei modelli 2D e 3D ed è stato valutato l'effetto della mushy zone constant
La metodologia SCRUM nello sviluppo di prodotti tangibili: il caso FILA
No full textGli obiettivi che questa tesi si pone sono analizzare se il framework Scrum possa essere implementato con successo nel processo di sviluppo di prodotti tangibili e valutare la necessità di modificarne alcune caratteristiche per adattarlo al contesto
Leghe di Alluminio AA6061 per impieghi aeronautici: caratterizzazione e qualifica per l'accreditamento Nadcap
Get PDFCon la seguente tesi si vuole seguire ed spiegare l'iter normativo che deve intraprendere l'azienda Siderforgerossi Group S.p.a. al fine di conseguire l'accreditamento Nadcap. Per comprendere questo processo di accreditamento si seguono, contestualmente alla caratterizzazione di una lega della serie AA6061, le direttive stilate nel documento AC7101/1 REV.G in cui si definiscono i limiti e i criteri da rispettare in previsione di un Audit da parte dell'ente PRI
A key tool to probe Euclid spectroscopy: Spectro-Photometric simulations of galaxies to unravel NISP's capabilities.
Get PDFWe present in this master Thesis the construction of Spectral Energy Distribution (SED) of galaxies
located at 0.3 2.5. The constructed SEDs will go through the Euclid Near Infrared
Spectrometer and Photometer (NISP) simulator hosted in the Istituto di Astrofisica Spaziale e Fisica
Cosmica (IASF; INAF) at Milan, aiming at reproducing spectra expected from the NISP mounted on
the Euclid telescope. These simulations will enable evaluating the spectroscopic survey performances
of the Euclid mission, and confirming that the telescope and its slitless NISP spectrometer will satisfy
the required detection limits for nebular emission lines.
This project was conceived in synergy with the Euclid Legacy Science Working Groups (SWGs), as a
"PILOT RUN" simulation test for spectroscopic data. The PILOT RUN includes a study of the
capabilities expected from the Euclid Wide and Deep fields' configurations.
The construction of the incident SEDs consists in computing a continuum using the Bruzual \&
Charlot(2003) models, calling out best-fit SED parameters available in the catalogs. The nebular
emission Balmer, [NII]6584,6549, [OII]3727,3729,
[OIII]5007,4959, [SII]6731,6717,
[SIII]9531,9069 and Paschen lines are added making use of calibrations available
in literature. We refer to common tools and indicators for emission lines analysis such as the Star
Formation Rate (SFR), the Baldwin-Phillips-Terlevich diagram (BTP), the Mass-Metallicity Relation
(MZR) and photoionization models. The emission lines are then integrated to the continuum
accounting for the calculated velocity dispersion of each galaxy. A photometric and spectroscopic
comparison of the incident SEDs with observational data is presented in this Thesis.
The incident SEDs then go through the Euclid NISP simulator that mimic the spectra expected from
the NISP spectrometer, generating the simulated spectra.
The PILOT RUN simulations are still ongoing, only part of the simulated spectra have been
constructed, limited to the galaxies from the CANDELS/GOODS-N catalog, corresponding to one out
of the 5 pointings planned to reach the required Deep Survey configuration, in terms of exposure
time. This pointing exactly matches the exposure time required for the Wide Survey configuration.
Thus, we present in this Thesis a first analysis of the available simulated data, and provide a
confirmation of the detection limit specifications for the continuum (i.e. H(AB) 19.5 mag) and
emission lines (i.e. Flux erg cm\textsuperscript{-2} s\textsuperscript{-1}
\mathrm{\AA}\textsuperscript{-1}) of the Euclid Wide Survey. The full set of the PILOT RUN
simulations will extensively complete the first picture given by our preliminary analysis.
We also provide an estimate of the NISP spectral resolution and finally present an analysis stacking
spectra located at 1.6 2.0, attesting for the great potential of the method in confirming
redshift determination, a crucial aspect for the Euclid mission
Scattering Processes via Tensor Network Simulations
Get PDFScattering processes are a crucial ingredient for the investigation of fundamental interactions. The ever-increasing amount of data produced at particle colliders has fuelled recent progresses in the field of scattering amplitudes computation. To date, on the numerical side, the results achieved are mainly based on Monte-Carlo simulations. In this Thesis the problem is attacked with a different approach: a real-time simulation of the dynamics of a 1+1 dimensional quantum field theory is performed, exploiting the powerful tensor network methods from many-body theory. A matrix product state representation of the asymptotic input states is identified, allowing for the preparation of the initial momentum wave packets. This initial state is then evolved and we aim to compute the S-matrix elements from the knowledge of the final state. We focus on a specific fermionic U(1)-gauge model, developing a set of tools which are relevant for a broader class of 1+1 dimensional quantum field theories with global or local symmetries
Iron-doped Lithium Niobate thin films on GaN: fabrication and characterization
Get PDFIn recent time ferroelectric thin films have attracted significant atten-tion due to the observation of several phenomena that manifest innew and intriguing ways. This is the case of photogalvanic effect,also known as bulk photovoltaic effect (BPVE), consisting in the spon-taneous onset of a small electrical current when a polar material isilluminated with a uniform light. A precise understanding of thiseffect could possibly lead to new applications, in particular in thefield of photovoltaics. In fact, as the mechanism of charge separationis completely different, those materials are not a priori bounded bythe theoretical Shockley–Queisser limit which applies to standardphotovoltaic devices such as p-n junctions in semiconductors.
In spite of this, the use of BVPE for photovoltaic energy conversion islimited by the smallness of the photogenerated current. In an effortto improve this aspect, a proposal has been made to use nano-sizedmaterials because in this case photogenerated charges could be ex-tracted more efficiently from the ferroelectric. In particular, iron-dopedLithium Niobate (Fe:LN) is one of the best known photogalvanic ma-terials and is therefore the ideal playground to test this approach,namely evidence an increase of the BVPE upon reducing the crystalsize to the nanoscale.
Unfortunately, lithium niobate has an intrinsically defective structureand its electrical properties are strongly affected both by its com-position and its structural properties, such as strain etc. A preciseknowledge of the film composition and structure is thus mandatory inorder to set the ground for forthcoming investigations. For this reason,in this work we undergo the task of characterizing a set of Fe:LN thinfilms epitaxially grown on GaN substrates on different conditions byRF-Magnetron sputtering. This activity, carried out in collaborationwith Università Ca’ Foscari (Venezia) and Laboratori Nazionali diLegnaro (LNL-INFN) is based on a combination of techniques andprotocols developed here for this specific kind of samples. The tech-niques used are HR-XRD, RBS, NRA and UV-Vis optical absorptionspectroscopy. The results show that the produced samples are charac-terized by a marked Li deficiency and a structural compressive straindetermined by the epitaxial relation with the substrate and provideuseful indications on how to improve the deposition parameters
