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Water and other volatiles (e.g. CO2, H2, CH4, etc.) are crucial components on Earth that ensure the habitability of the planet and play an important role in many geological processes. Small aliquots of these fluids can be preserved in the geological record as fluid inclusions and can provide valuable information about the physical and chemical environment in which they formed. The ocean is the largest water reservoir on the Earth's surface, and seawater participates in important water-rock reactions such as hydrothermal alteration of the ocean floor, a process that is currently in the spotlight for hypotheses on the origin of life, as it is an environment where generation of abiotic carbohydrates occur. The ocean chemistry varied in the geologic past to reflect major changes in the intensity of weathering, rates of midocean ridge hydrothermal discharge, changes in the climate and atmospheric CO2 concentration, and also played an important part in mass extinction events. Understanding the history of Earth's ancient oceans may hold the key to answer some of the important questions about the future of the Earth. Today, oceans hold valuable resources, such as offshore basalt formations which have been considered for submarine CO2 sequestration to mitigate greenhouse gas emissions associated with global warming. In the chapters of this dissertation, the reader will be presented with studies using fluid inclusions to advance our knowledge about the chemical evolution of seawater and reaction kinetics involving CO2, seawater and olivine – an abundant mineral in the oceanic lithosphere. Chapter I "Redox conditions in Late Permian seawater based on trace element ratios in fluid inclusions in halite from the Polish Zechstein Basin" describes application of a new redox proxy for paleo-seawater that involves analysis of redox-sensitive trace elements (e.g., Fe, Mn, U, V, Mo) in ancient seawater trapped as fluid inclusions in halite. Chapter II "Partitioning behavior of trace elements during evaporation of seawater" investigates the behavior of trace elements during the evaporation of seawater. This information is required to interpret trace element data from fluid inclusions in halite. In Chapter III "In situ monitoring of the carbonation of olivine under conditions relevant to carbon capture and storage using synthetic fluid inclusion micro-reactors: Determination of reaction rates", fluid inclusions are used as micro-reactors to monitor the reaction progress of olivine carbonation in situ and in real time at elevated temperatures (50-200 °C) and pressures using non-destructive analytical techniques such as Raman spectroscopy. / Doctor of Philosophy / Many geological processes on Earth involve water and other volatiles (e.g. CO2, H2, CH4, etc.) which are crucial components that ensure the habitability of the planet. These fluids can be preserved in the geological record in the form of fluid inclusions which are small aliquots of fluids trapped in minerals that provide information about the physical and chemical environment in which they formed. The majority of water on the Earth's surface is stored in the oceans. Seawater participates in important water-rock reactions, one of which is the hydrothermal alteration of the ocean floor. This reaction is in the spotlight currently because it represents an environment where generation of abiotic carbohydrates occur, giving rise for hypotheses about the origin of life on Earth. The chemical composition of seawater varied in the geologic past reflecting major changes in the intensity of weathering, discharge rate of midocean ridge hydrothermal systems, climate, and atmospheric CO2 concentration, and affected the survival of various marine species throughout Earth's history. For example, periodic extensions of oxygen minimum zones in the oceans played an important part in mass extinction events in the last 488 million years. Understanding the history of Earth's ancient oceans may hold the key to answer some of the important questions about the future of the Earth. Today, oceans hold valuable resources, such as offshore basalt formations which have been considered for submarine CO2 sequestration to mitigate greenhouse gas emissions associated with global warming. This dissertation explores ways to use fluid inclusions to advance our knowledge about the chemical evolution of seawater in the past and present, and the reaction of seawater with CO2 and olivine – an abundant mineral in the oceanic lithosphere – to facilitate long-term storage of CO2 in minerals to decrease the rate of global warming. Chapter I describes the application of a new redox proxy for paleo-seawater that involves analysis of redox-sensitive trace elements (elements whose solubility changes significantly as the oxidation state changes, such as Fe, Mn, U, V, Mo) in ancient seawater trapped as fluid inclusions in halite. The results suggest that trace element abundances in fluid inclusions in halite vary in response to redox changes in seawater and provide a potential redox proxy. Chapter II investigates the behavior of trace elements during the evaporation of seawater. This information is required to interpret trace element data from fluid inclusions in halite. The results of this study indicate that some elements remain in the water during evaporation of seawater (e.g. Li, B, Mo, U), while others are partially removed by precipitation of various mineral phases (e.g. Ba, Sr, Cs, Rb, Mn, V) as seawater evaporates. In Chapter III, fluid inclusions are used as micro-reactors to monitor the reaction progress of olivine carbonation in situ and in real time at elevated temperatures (50-200 °C) and pressures using non-destructive analytical techniques such as Raman spectroscopy. The results highlight that this reaction occurs rapidly, which makes it an ideal candidate for safe storage of CO2 by commercial CO2 injection projects in mafic and ultramafic rocks.

This thesis explores the evaporation kinetics of various polymer-solvent and binary solvent mixtures to explore possible connections between the solutions properties and their evaporation process. By looking at the evaporation of polymer-solutions and binary-solvent solutions, through the change in weight as the solvent evaporates and the evaporation rate of the evaporation process, potential connections could be found. The results indicate that the presence of polymers influence the solvent evaporation, with polystyrene (PS) generally accelerating and polymethyl methacrylate (PMMA) either decelerating or having minimal impact on evaporation rates. Binary solvent mixtures exhibited non-proportional increases in evaporation rates, suggesting complex intermolecular interactions, but no apparent patterns between their properties and deviation in the evaporation process. This would need further research to find possible connections to be able to predict the evaporation process. But these findings highlight the importance of understanding polymer-solvent compatibility and evaporation dynamics to enhance performance and to identify environmentally friendly solvents for organic photovoltaic (OPV) cell fabrication. / Detta examensarbete undersöker avdunstningskinetiken hos olika polymer-lösningsmedel och binära lösningsmedelsblandningar för att utforska möjliga samband mellan lösningarnas egenskaper och deras avdunstningsprocess. Genom att studera avdunstningen av polymer-lösningar och binära lösningsmedelslösningar, genom förändringen i vikt när lösningsmedlet avdunstar och avdunstningshastigheten, kan potentiella samband identifieras. Resultaten indikerar att närvaron av polymerer påverkar lösningsmedlets avdunstning, där polystyren (PS) generellt accelererar och polymetylmetakrylat (PMMA) antingen decelererar eller har minimal inverkan på avdunstningshastigheterna. Binära lösningsmedelsblandningar visade icke-proportionella ökningar i avdunstningstider, vilket tyder på komplexa intermolekylära interaktioner, men inga tydliga mönster mellan deras egenskaper och avvikelser i avdunstningsprocessen kunde identifieras. Ytterligare forskning behövs för att finna möjliga samband för att kunna förutsäga avdunstningsprocessen. Dessa fynd understryker vikten av att förstå polymer-lösningsmedelskompatibilitet och avdunstningsdynamik för att förbättra effektiviteten och kunna identifiera miljövänliga lösningsmedel för tillverkning av organiska solceller (OPV).

Conclusions: the absorption hygrometer cannot be used satisfactorily to measure differences in evaporation from small plots. / Master of Science

[EN] The main objective of this work is the modeling of diesel sprays under engine conditions, including the atomization, transport and evaporation processes pivotal in the diesel spray formation and its development. For this purpose, an Eulerian single fluid model, embedded in a RANS environment, is implemented in the CFD platform OpenFOAM. The modeling approach implemented here is based on the ⅀-Y model. The model is founded on the assumption of flow scales separation. In actual injection systems, it can be assumed that the flow exiting the nozzle is operating at large Reynolds and Weber numbers and thus, it is possible to assume a separation of features such as mass transport (large scales) from the atomization process occurring at smaller scales. The liquid/gas mixture is treated as a pseudo-fluid with variable density and which flows with a single velocity field. Moreover, the mean geometry of the liquid structures can be characterized by modeling the mean surface area of the liquid-gas interphase per unit of volume. Additionally, an evaporation model has been developed around the particular characteristics of the current engine technologies. This means that vaporization process is limited by fuel-air mixing rate and fuel droplets evaporate as long as there is enough air for them to heat up and vaporize. Consequently, the evaporation model is based on the Locally Homogeneous Flow (LHF) approach. Under the assumption of an adiabatic mixing, in the liquid/vapor region, the spray is supposed to have a trend towards adiabatic saturation conditions and to determine this equilibrium between phases Raoult's ideal law is considered. Finally, the spray model is coupled with an advanced combustion model based on approximated diffusion flames (ADF), which reduces the computational effort especially for complex fuels and is a natural step for modeling diesel sprays. First, the model is applied to a basic external flow case under non-vaporizing conditions, extremely convenient due to both the experimental database available and the symmetric layout which allows important simplification of the modeling effort. Good agreement between computational results and experimental data is observed, which encourages its application to a more complex configuration. Secondly, the model is applied to the "Spray A" from the Engine Combustion Network (ECN), under non-vaporizing conditions, in order to reproduce the internal structure of diesel sprays as well as to produce accurate predictions of SMD droplets sizes. Finally, vaporizing "Spray A" studies are conducted together with the baseline reacting condition of this database. The calculated spray penetration, liquid length, spray velocities, ignition delay and lift-off length are compared with experimental data and analysed in detail. / [ES] El objetivo principal de este trabajo es el modelado de chorros diésel en condiciones de motor, incluyendo los fenómenos de atomización, transporte y evaporación fundamentales en la formación y desarrollo del chorro. Para este fin, se implementa un modelo de spray euleriano de tipo monofluido en un entorno RANS en la plataforma CFD OpenFOAM. El enfoque de modelado aplicado aquí sigue la idea de un modelo del tipo ⅀-Y. El modelo se fundamenta en la hipótesis de separación de escalas del flujo. En los sistemas de inyección actuales, es posible asumir que el flujo que sale de la tobera opera a altos números de Reynolds y Webber y por tanto, es posible considerar la independencia de fenómenos como el transporte de masa (grandes escalas del flujo) de los procesos de atomización que ocurren a escalas menores. La mezcla líquido/gas se trata como un pseudo-fluido con densidad variable y que fluye según un único campo de velocidad. Además, la geometría promedio de las estructuras de líquido se puede caracterizar mediante el modelado de la superficie de la interfase líquido/gas por unidad de volumen. Completando el modelo de chorro, se ha desarrollado un modelo de evaporación alrededor de las características particulares de las tecnologías actuales de los motores. Esto supone que el proceso de evaporación está controlado por mezcla aire-combustible y las gotas de combustible se evaporan siempre que exista suficiente aire para calentarlas y evaporarlas. Debido a esto, el modelo de evaporación implementado está basado en el enfoque de Flujos Localmente Homogéneos (LHF). Considerando una mezcla adiabática, en la región líquido/vapor, se supone que el chorro tiende a las condiciones adiabáticas de saturación y para determinar este equilibrio entre fases, se utiliza la ley ideal de Raoult. Finalmente, el modelo de chorro se acopla con un modelo avanzado de combustión basado en llamas de difusión aproximadas (ADF), que reduce el coste computacional especialmente para combustibles complejos y supone el paso lógico en el desarrollo del modelo para simular chorros diesel. En primer lugar, el modelo se aplica al cálculo de un caso básico de flujo externo no evaporativo, muy adecuado tanto por la extensa base de datos experimentales disponible como por la simetría geométrica que presenta, permitiendo una importante simplificación de la simulación. Los resultados obtenidos presentan un buen acuerdo con los experimentos, lo cual estimula su aplicación en configuraciones más complejas. En segundo lugar, el modelo se aplica al cálculo del "Spray A" del Engine Combustion Network (ECN), no evaporativo, para reproducir la estructura interna del chorro diesel así como predecir tamaños de gota (SMD) de forma precisa. Finalmente, se realizan estudios evaporativos del "Spray A" junto con la condición nominal reactiva de esta base de datos. La penetración de vapor, la longitud líquida, velocidad, el tiempo de retraso y la longitud de despegue de llama calculados se comparan con los datos experimentales y se analizan en detalle. / [CA] L'objectiu principal d'aquest treball és el modelatge de dolls dièsel en condicions de motor, incloent els fenòmens d'atomització, transport i evaporació fonamentals en la formació i desenvolupament del doll. Amb aquesta finalitat, s'implementa un model de doll eulerià de tipus monofluid en un entorn RANS a la plataforma CFD OpenFOAM. L'enfocament de modelatge aplicat ací segueix la idea d'un model del tipus ⅀-Y. El model es fonamenta en la hipòtesi de separació d'escales del flux. En els sistemes d'injecció actuals, és possible assumir que el flux que surt de la tovera opera a alts nombres de Reynolds i Webber, i per tant és possible considerar la independència de fenòmens com el transport de massa (grans escales del flux) dels processos d'atomització que ocorren a escales menors. La mescla líquid / gas es tracta com un pseudo-fluid amb densitat variable i que flueix segons un únic camp de velocitat. A més, la geometria mitjana de les estructures de líquid es pot caracteritzar mitjançant el modelatge de la superfície de la interfase líquid / gas per unitat de volum. Completant el model, s'ha desenvolupat un model d'evaporació al voltant de les característiques particulars de les tecnologies actuals dels motors. Això suposa que el procés d'evaporació està controlat per la mescla aire-combustible i les gotes de combustible s'evaporen sempre que hi hagi suficient aire per escalfar i evaporar. A causa d'això, el model d'evaporació implementat està basat en el plantejament de fluxos Localment Homogenis (LHF). Considerant una mescla adiabàtica, a la regió líquid / vapor, se suposa que el doll tendeix a les condicions adiabàtiques de saturació i per determinar aquest equilibri entre fases, s'utilitza la llei ideal de Raoult. Finalment, el model de doll s'acobla amb un model avançat de combustió basat en flamelets de difusió aproximades (ADF), que redueix el cost computacional especialment per a combustibles complexos i suposa el pas lògic en el desenvolupament del model per simular dolls dièsel. En primer lloc, el model s'aplica al càlcul d'un cas bàsic de flux extern no evaporatiu, molt adequat tant per l'extensa base de dades experimentals disponible com per la simetria geomètrica que presenta, permetent una important simplificació de la simulació. Els resultats obtinguts presenten un bon acord amb els experiments, la qual cosa estimula la seva aplicació en configuracions més complexes. En segon lloc, el model s'aplica al càlcul del "Spray A" no evaporatiu de la xarxa Engine Combustion Network (ECN), per reproduir l'estructura interna del doll dièsel així com predir mides de gota (SMD) de forma precisa. Finalment, es realitzen estudis evaporatius del "Spray A" juntament amb la condició nominal reactiva d'aquesta base de dades. La penetració de vapor, la longitud líquida, velocitat, el temps de retard i la longitud d'enlairament de flama calculats es comparen amb les dades experimentals i s'analitzen en detall. / Pandal Blanco, A. (2016). Implementation and Development of an Eulerian Spray Model for CFD simulations of diesel Sprays [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/68490

No / A method for measuring the evaporation kinetics of pure solvents and solutions containing Cd3P2 quantum dots (QDs) in SiO/SiO2 rolled-up microtube (RUT) resonators is reported. The QDs serve as wavelength-tunable fluorescent sources for the RUT resonator. The first-order kinetic constant (295 K) of the evaporation of toluene embedded in a RUT (D = 9.10 μm) is evaluated (0.055 min−1). / Doctoral Program Education of China. Grant Number: 20110111120008; Alexander von Humboldt Foundation

The purpose of this thesis is to determine the effect of hexadecanol on the populations of Pseudomonas and Alcaligenes species in reservoirs and determine their ability to utilize this compound as a carbon source.