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A comprehensive ionic reaction model for mineral carbonation in the cement industry
Full text linkopenThis thesis develops a comprehensive ionic reaction model to examine mineral carbonation processes in supplementary cementitious materials, addressing a significant opportunity to reduce carbon dioxide emissions from the cement industry. The work focuses on the complex reaction kinetics and transport phenomena involved when cementitious materials interact with CO2 in aqueous environments. The research introduces an innovative ionic reaction model that effectively captures physicochemical processes, including calcium leaching from supplementary cementitious materials, CO2 dissolution and carbonate speciation reactions, solid surface reaction, and calcium carbonate precipitation. Unlike traditional shrinking core or two-film models, this approach explicitly accounts for the evolution of solution chemistry and the dynamic interplay between reaction kinetics and diffusion limitations. Parameter estimation was conducted using various optimization techniques (Genetic Algorithm, Differential Evolution, and a hybrid approach), with the model demonstrating excellent agreement with experimental measurements of calcium hydroxide consumption, pH evolution, and calcium carbonate formation. The analysis revealed three distinct kinetic regimes during carbonation: an initial reaction-limited phase dominated by Ca(OH)2 dissolution, a transition phase with competing mechanisms, and a final diffusion-limited phase controlled by transport through precipitated layers on the particles. The model provides valuable insights into carbonate speciation dynamics, the relative contributions of different calcium sources to carbonation, and the progressive development of diffusion barriers. These findings establish a foundation for optimizing carbonation processes in supplementary cementitious materials, potentially enabling more efficient CO2 utilization in the cement industry and contributing to decarbonization efforts through carbon mineralization.This thesis develops a comprehensive ionic reaction model to examine mineral carbonation processes in supplementary cementitious materials, addressing a significant opportunity to reduce carbon dioxide emissions from the cement industry. The work focuses on the complex reaction kinetics and transport phenomena involved when cementitious materials interact with CO2 in aqueous environments. The research introduces an innovative ionic reaction model that effectively captures physicochemical processes, including calcium leaching from supplementary cementitious materials, CO2 dissolution and carbonate speciation reactions, solid surface reaction, and calcium carbonate precipitation. Unlike traditional shrinking core or two-film models, this approach explicitly accounts for the evolution of solution chemistry and the dynamic interplay between reaction kinetics and diffusion limitations. Parameter estimation was conducted using various optimization techniques (Genetic Algorithm, Differential Evolution, and a hybrid approach), with the model demonstrating excellent agreement with experimental measurements of calcium hydroxide consumption, pH evolution, and calcium carbonate formation. The analysis revealed three distinct kinetic regimes during carbonation: an initial reaction-limited phase dominated by Ca(OH)2 dissolution, a transition phase with competing mechanisms, and a final diffusion-limited phase controlled by transport through precipitated layers on the particles. The model provides valuable insights into carbonate speciation dynamics, the relative contributions of different calcium sources to carbonation, and the progressive development of diffusion barriers. These findings establish a foundation for optimizing carbonation processes in supplementary cementitious materials, potentially enabling more efficient CO2 utilization in the cement industry and contributing to decarbonization efforts through carbon mineralization
Construction methodology of flanked viaducts by "balanced cantilever" method with parallel launching. Analysis of the interaction between the launching girder and viaducts.
No full textopenL’ingegneria di costruzione, intesa come la branchia dell’ingegneria che studia le metodologie e le fasi costruttive nella realizzazione di un’opera permanente, analizza numerose fasi in cui lo schema statico della struttura varia continuamente. Spesso, tali fasi risultano critiche o addirittura dimensionanti per le stesse strutture permanenti, più dei carichi di progetto. La costruzione di viadotti con la metodologia “balanced cantilever” richiede grande attenzione a tali fasi costruttive, in particolare se è previsto l’utilizzo di un carrovaro, ossia un macchinario efficiente ma particolarmente gravoso per la struttura stessa. Questo elaborato, basandosi su un caso studio reale, indaga alcune delle fasi costruttive più critiche nel varo di viadotti paralleli con le metodologia “balanced cantilever”, evidenziando gli effetti che la mutua interazione tra carrovaro e impalcato generano nel carrovaro stesso. In particolare, si evidenziano le carenze dovute ad un’analisi di tale macchinario su vincoli infinitamente rigidi, che trascura le deformabilità flesso-torsionali degli impalcati, generando incertezze nella determinazione delle sollecitazioni utilizzate per le verifiche strutturali degli elementi del carrovaro stesso.Construction engineering, the branch of engineering that studies the methodologies and construction phases in the creation of a permanent structure, analyzes numerous phases in which the static scheme of the structure varies continuously. Often, these phases are critical or even dimensioning for the permanent structures themselves, more than the design loads. The construction of viaducts with the “balanced cantilever” methodology requires great attention to these construction phases, in particular if the use of a launching gantry is planned, which is an efficient machine but particularly burdensome for the structure itself. This paper, based on a real case study, investigates some of the most critical construction phases in the launching of parallel viaducts with the “balanced cantilever” methodology, highlighting the effects that the mutual interaction between the launching gantry and the deck generate in the launching gantry itself. In particular, the shortcomings due to an analysis of this machinery on infinitely rigid constraints are highlighted, which neglects the flexural-torsional deformability of the decks, generating uncertainties in the determination of the stresses used for the structural checks of the elements of the gantry itself
Nutrition and Athletic Performance: Comparison between Plant-Based and Omnivorous Diets in Athletes
No full textreservedLa crescente diffusione delle diete vegetariane, caratterizzate dalla parziale o totale
esclusione di alimenti di origine animale, sta guadagnando sempre più attenzione nel mondo
dello sport. Un numero crescente di atleti adotta questo tipo di alimentazione con l’obiettivo
di ottimizzare le proprie performance, sia in discipline di forza che di resistenza.
Le diete vegetariane sono spesso associate a numerosi benefici per la salute, tra cui la
riduzione del rischio cardiovascolare, il miglioramento nella gestione del peso corporeo e
una maggiore sostenibilità ambientale. Tuttavia, è essenziale valutare se queste diete siano
in grado di soddisfare i fabbisogni nutrizionali specifici degli atleti, considerando l’importanza
di una pianificazione attenta per garantire l’apporto adeguato di proteine, vitamine e minerali.
Questa tesi analizza le più recenti evidenze scientifiche, confrontando la dieta vegetariana
con quella onnivora in relazione alle prestazioni sportive. Vengono discussi i benefici e le
criticità di entrambi gli approcci alimentari, con particolare attenzione all’impatto sul
recupero, sulla composizione corporea e sulla capacità di sostenere gli elevati carichi di
lavoro richiesti agli atleti. Le conclusioni offrono spunti utili per guidare le scelte alimentari
degli sportivi, considerando sia gli aspetti nutrizionali che quelli legati alla performance.The growing popularity of vegetarian diets, characterized by the partial or total exclusion of animal-based foods, is gaining increasing attention in the world of sports. A rising number of athletes are adopting this type of diet with the goal of optimizing their performance in both strength and endurance disciplines.
Vegetarian diets are often associated with numerous health benefits, including a reduced risk of cardiovascular disease, improved weight management, and greater environmental sustainability. However, it is essential to evaluate whether these diets can meet the specific nutritional needs of athletes, considering the importance of careful planning to ensure an adequate intake of proteins, vitamins, and minerals.
This thesis analyzes the latest scientific evidence, comparing vegetarian and omnivorous diets in relation to athletic performance. The benefits and challenges of both dietary approaches are discussed, with a particular focus on their impact on recovery, body composition, and the ability to sustain the high workload demands placed on athletes. The conclusions provide valuable insights to guide athletes’ dietary choices, taking into account both nutritional aspects and performance-related considerations
Decoding the role of cysteine metabolism in angiogenesis
No full textreservedAngiogenesis is the process by which new blood vessels are formed from pre
existing ones in response to signals triggered by pathophysiological conditions,
such as wound healing or cancer. In this study, we aim to decode the role of cysteine
in angiogenesis, specifically how its deprivation, or the inhibition of the
transsulfuration pathway involved in cysteine synthesis affect endothelial cell
survival by triggering ferroptosis.
Since endothelial cells can exist in different metabolic states (quiescent, QECs, or
proliferating, PECs), we investigate whether cysteine deprivation has differential
effects depending on the cell's metabolic state.
Our data show that cysteine deprivation leads to cell death by ferroptosis in PECs,
a form of cell death characterized by the accumulation of lipid peroxides,
culminating in membrane rupture. In contrast, QECs exhibit an inherent resistance
to cysteine starvation compared to PECs, likely because, unlike PECs that rely on
xCT (the cystine/glutamate antiporter) as their main source of cysteine, QECs use
TSP as their primary cysteine source.
Extracellular cysteine limitation is a feature of various tumors. A deeper
understanding of the pathways involved in resistance to cysteine starvation could
aid in developing new therapies aimed at inhibiting these pathways, ultimately
improving prognosis by targeting the formation of new blood vessels, essential for
tumor growth
Between sky and earth. Ukrainian women in Veneto, between solidarity and uncertainty
No full textreservedL'elaborato in questione si pone come obiettivo quello di esplorare le esperienze delle donne ucraine rifugiatesi in Italia dopo il conflitto contro la Russia scoppiato nel 2022, più precisamente nella regione Veneto. Tramite un’analisi qualitativa condotta con delle interviste semi-strutturate, la ricerca approfondisce i percorsi personali delle intervistate, concentrandosi su determinati aspetti quali l’apprendimento della lingua, le opportunità di accesso al lavoro, il ruolo delle reti etniche e le difficoltà di adattamento. L’obiettivo è quello di comprendere quali sono le dinamiche che facilitano o ostacolano il processo di integrazione, cercando di individuare l’impatto delle politiche di accoglienza italiane. La tesi ambisce a dare voce a queste donne, raccontando le loro storie, i loro bisogni e le loro prospettive per il futuro.This paper aims to explore the experiences of Ukrainian women refugees in Italy after the conflict against Russia in 2022, more specifically in the Veneto region. Through a qualitative analysis conducted with semi-structured interviews, the research explores in depth the personal journeys of the interviewees, focusing on certain aspects such as language learning, opportunities to access employment, the role of ethnic networks, and difficulties in adapting. The goal is to understand which dynamics facilitate or inhibit the integration process, trying to identify the impact of Italian reception policies. The thesis aims to give voice to these women, telling their stories, their needs and their prospects for the future
The genesis of the novella Il figlio cambiato: between folklore and cognitive relativism
No full textreservedL’elaborato è incentrato sulla genesi testuale della novella Il figlio cambiato di Luigi Pirandello: verranno, infatti, analizzate le numerose varianti d’autore presenti nelle edizioni della novella, a partire dalla prima stampa sulla "Riviera ligure" con il titolo "Le Nonne", fino ad arrivare alla trasposizione teatrale "La Favola del figlio cambiato". Si tratta di una novella incentrata sulla tematica del folklore siciliano, in particolare sulla leggenda delle “Donne” e dello scambio di un infante con un altro. Si approfondirà così questa leggenda e si tratterà del rapporto di Pirandello con l’occulto e la superstizione, prendendo ad esempio altri testi pirandelliani che verranno messi in collegamento con quello della novella. Si parlerà poi nell’analisi critica del testo, del fatto che la vicenda narrativa viene raccontata secondo diversi punti di vista; la modifica del narratore nella seconda edizione porterà, infatti, alla relativizzazione della verità conoscitiva e alla messa in discussione da parte del lettore del punto di vista popolare. L’incomunicabilità tra i personaggi della novella, così come l’incapacità del regime fascista di comprendere appieno La Favola del figlio cambiato, è la rappresentazione pratica della teoria del relativismo pirandelliano e la piena conferma, nel mondo moderno, dell’incomunicabilità tra gli individui, dal momento che ognuno è portare di un proprio modo di vedere la realtà
Optimizing Resource Recovery from Construction and Demolition Waste through Pinch Analysis: A Methodological proposal
No full textopenConstruction and demolition (C&D) debris constitutes a significant proportion of global solid waste generation, contributing to critical issues of resource use, environmental destruction, and excessive dependency on landfills. Now, with the world reaching new heights of urbanization and construction activity, sustainable waste management solutions are more relevant than ever, as these types of waste can have detrimental environmental and economic ramifications if not disposed of properly.
This thesis explored the potential of applying an energy and process optimization tool, referred to as Pinch Analysis, towards the resource recovery from C&D waste. Bringing this concept to the management of material flow, the study investigates a systemic approach in which the design of methods to minimize waste generation, maximize reuse potential, and improve recycling are vital.
It focuses on a proposed methodology which designs and characterizes and evaluates waste streams for the different categories of C&D which is despite the current unwieldy scavenging of material streams, implementing the Pinch Analysis precept to determine how to separate and thus reuse material within heterogeneous streams. It takes a detailed dive into high value substrates such as concrete, metals and wood that either get lost directly and then in existing recycling systems, thereby the recycling systems that exist today are to all intents and purposes useless. The effect of submerged data on optimization opportunities is considered and the benefits of applying Pinch Analysis to solid waste are outlined
These results suggest that a systematic procedure such as that provided by Pinch Analysis can provide a practical alternative in the field of C&D waste management optimization. This approach may foster a more sustainable building practice by assisting in determining the maximum limits for material interchangeability and by optimizing waste disposal policies in order to minimize landfill and emissions associated with material extraction and disposal. Pinch Analysis also accommodates circular economy practices in which the reclaimed material is re-entered into the building material supply chain, relieving pressure on the virgin material extraction and promoting closing the loops within the building processes.
In sum, this study shows the transformative potential that Pinch Analysis presents as a strategic approach to progress sustainability in construction waste management. By incorporating this methodology into existing waste processing systems, policymakers, industry representatives, and waste management practitioners can transition toward material efficiency, reduce environmental footprints, and foster a more resource-efficient and resilient urban system. The results of this study improve the theoretical part of Pinch Analysis application and suggest practical recommendations for adopting Pinch Analysis method for complex waste management systems, making it a useful tool to help ensure sustainability in the built environment.Construction and demolition (C&D) debris constitutes a significant proportion of global solid waste generation, contributing to critical issues of resource use, environmental destruction, and excessive dependency on landfills. Now, with the world reaching new heights of urbanization and construction activity, sustainable waste management solutions are more relevant than ever, as these types of waste can have detrimental environmental and economic ramifications if not disposed of properly.
This thesis explored the potential of applying an energy and process optimization tool, referred to as Pinch Analysis, towards the resource recovery from C&D waste. Bringing this concept to the management of material flow, the study investigates a systemic approach in which the design of methods to minimize waste generation, maximize reuse potential, and improve recycling are vital.
It focuses on a proposed methodology which designs and characterizes and evaluates waste streams for the different categories of C&D which is despite the current unwieldy scavenging of material streams, implementing the Pinch Analysis precept to determine how to separate and thus reuse material within heterogeneous streams. It takes a detailed dive into high value substrates such as concrete, metals and wood that either get lost directly and then in existing recycling systems, thereby the recycling systems that exist today are to all intents and purposes useless. The effect of submerged data on optimization opportunities is considered and the benefits of applying Pinch Analysis to solid waste are outlined
These results suggest that a systematic procedure such as that provided by Pinch Analysis can provide a practical alternative in the field of C&D waste management optimization. This approach may foster a more sustainable building practice by assisting in determining the maximum limits for material interchangeability and by optimizing waste disposal policies in order to minimize landfill and emissions associated with material extraction and disposal. Pinch Analysis also accommodates circular economy practices in which the reclaimed material is re-entered into the building material supply chain, relieving pressure on the virgin material extraction and promoting closing the loops within the building processes.
In sum, this study shows the transformative potential that Pinch Analysis presents as a strategic approach to progress sustainability in construction waste management. By incorporating this methodology into existing waste processing systems, policymakers, industry representatives, and waste management practitioners can transition toward material efficiency, reduce environmental footprints, and foster a more resource-efficient and resilient urban system. The results of this study improve the theoretical part of Pinch Analysis application and suggest practical recommendations for adopting Pinch Analysis method for complex waste management systems, making it a useful tool to help ensure sustainability in the built environment
MILP framework for integrating seasonal thermal storage in energy hubs: economic and performance optimization
No full textreservedThis thesis investigates the integration of Seasonal Thermal Energy Storage (STES) within a multi-energy optimization framework, using the REHO tool developed by the IPESE group at EPFL. The objective is to evaluate the techno-economic and environmental impact of STES in a fully electrified energy hub, assessing its ability to improve system efficiency, reduce emissions, and enhance energy independence.
An initial optimization is conducted without considering temperature dynamics in the storage system, as commonly assumed in literature. However, a post-process analysis reveals that neglecting the storage outlet temperature leads to technically infeasible results, due to the temperature mismatch with the district heating network (DHN) requirements. To address this issue, a heat pump is introduced in a refined configuration to ensure operational feasibility.
The analysis then progresses by introducing a minimum temperature constraint on the storage medium. Results show that enforcing this thermal limit improves the performance of the heat pump, significantly reducing electricity imports and operational expenditures. At the same time, however, maintaining the minimum storage temperature increases the required storage volume, leading to higher capital costs.
Ultimately, the findings demonstrate that STES is an effective strategy to address seasonal energy imbalances and reduce grid dependence. Nonetheless, the minimum allowable storage temperature proves to be a critical parameter, influencing not only the energy performance of the system but also the design and dimensioning of key infrastructure components
EMALS Technology: Electromagnetic Aircraft Launch System
No full textopenQuesta relazione spiegherà le procedure tali per cui un aeromobile militare riesce a decollare da una portaerei con una pista relativamente corta.
Verrà discusso come questo sia reso possibile attraverso la tradizionale catapulta a vapore e la sua successiva evoluzione con la tecnologia EMALS.
Sarà dunque proposta una visione parallela di entrambi i sistemi mettendo in evidenza pro e contro di ciascuna.This review will explain the procedures by which a military aircraft can take off from a short runway of an aircraft carrier.
The traditional steam catapult and its evolution with EMALS technology will be analysed.
Subsequently, a compared view of both systems will be proposed, highlighting the pros and cons of each
Patronage as a guarantee in banks' loans
No full textopenLe lettere di patronage costituiscono una peculiare forma di garanzia, impiegata come strumento, nell’alveo di una più complessa operazione di finanziamento - tipicamente bancario -, informato alla causa di offrire una sufficiente cautela al diritto di credito della banca, facilitando, al contempo, l’apertura, il rinnovo o il mantenimento di una linea di credito in favore di un terzo soggetto, c.d. patrocinato, rispetto all’emittente del documento, c.d. patrocinante. L’elaborato si propone, preliminarmente, di dare contezza dei tratti descrittivi e funzionali della fattispecie e della sua natura giuridica, anche eseguendo un raffronto con altre forme di garanzia. Seguono considerazioni sulla necessarietà di evitare di adottare un approccio generalizzato alla figura in esame, posta la varietà contenutistica che la connota, al fine di operare una appropriata interpretazione. La ricerca è mirata alla definizione della disciplina che informa il patronage - fattispecie giuridicamente atipica -, in particolare, vagliando, sul versante pratico, la possibilità che un improprio confezionamento della lettera dia luogo a qualificazioni sfavorevoli, quantomeno per uno dei soggetti involti nel rapporto, oppure alla creazione di un contratto innominato misto anziché di una convenzione atipica con connotati propri, e l’opportunità di applicare, per altro verso, a documenti che contengano dichiarazioni in toto riconducibili alla presente garanzia autonoma, le norme in tema di fideiussione mediante il ricorso al criterio ermeneutico dell’analogia. Segue, a concludere, la disamina di ulteriori aspetti attinenti: la segnalazione alla Centrale Rischi della Banca d’Italia, l’iscrizione in bilancio e i profili fiscali