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Charge transport and structural dynamics in a homologous pair of ammonium and phosphonium based room temperature ionic liquids (ILs) have been characterized over a wide temperature range using broadband dielectric spectroscopy and quasi-elastic light scattering spectroscopy. We have found that the ionic conductivity of the phosphonium based IL is significantly enhanced relative to the ammonium homolog, and this increase is primarily a result of a lower glass transition temperature and higher ion mobility. Additionally, these ILs exhibit pronounced secondary relaxations which are strongly influenced by the atomic identity of the cation charge center. While the secondary relaxation in the phosphonium IL has the expected Arrhenius temperature dependence characteristic of local beta relaxations, the corresponding relaxation process in the ammonium IL was found to exhibit a mildly non-Arrhenius temperature dependence in the measured temperature range—indicative of molecular cooperativity. These differences in both local and long-range molecular dynamics are a direct reflection of the subtly different inter-ionic interactions and mesoscale structures found in these homologous ILs.

This thesis deals with the study of transport properties of integer and fractional QH edge states and it is based on the work I performed during my Ph.D. studies. The focus of this thesis is on Luttinger liquids far from equilibrium and their relaxation dynamics. Since Boltzmann, a fundamental aspect of statistical mechanics has been the understanding of the emergence of an equilibrium state. Interactions play a crucial role in the thermalization process that drives a system through states described by the Gibbs equilibrium ensemble. Therefore, it seems counterintuitive that a strongly interacting system, such as the Luttinger liquid, should not present any relaxation dynamics. This peculiar fact is due to the integrability of the Luttinger model, i.e. the existence of an infinite number of conserved quantities that precludes the equilibration process. However, in the past few years it has become clear that integrable systems can present some kind of relaxation, even though not towards the Gibbs equilibrium ensemble. Remarkably, the necessity of correctly taking into account some particular non-equilibrium configurations, also revealed the necessity of modifying bosonization, a technique widely used to study strongly interacting systems in one dimension. In this work we focus on three different cases: • Relaxation of high energy electrons injected in a ν = 1/3 chiral Luttinger liquid and in a standard Luttinger liquid. • Heating and the emergence of effective temperatures in a Quantum Hall system at fractional filling fraction ν = 2/3 partitioned by a Quantum Point Contact. • Effect of relaxation on shot-noise measurement of the quasi-particle charge in a ν = 2 QH state.

In fire debris analysis, substrate contribution refers to compounds present within the material collected that can interfere with the instrumental detection of ignitable liquids or contribute petroleum or alcohol-based compounds, which may complicate the interpretation. The concept of substrate contribution was brought to light by "The petroleum-laced background" by Lentini et al. focusing on commercial products (e.g. tennis shoes, magazines, etc.), the publication successfully illustrated that these products can produce chromatograms similar to those generated by the presence of petroleum-based ignitable liquids (ILs). As a result, Lentini et al. demonstrated that fire debris analysts can identify the presence of ignitable liquids without realizing the compounds in question might be the result of the manufacturing processes, and are inherent to the substrate in question. Therefore, the findings may or may not be probative. Gasoline is easily accessible and is frequently used by arsonists. As such, fire debris analysis focuses primarily on petroleum-based compounds. However, oxygenated solvents, which encompass all oxygen-containing compounds as defined by the American Society for Testing and Materials (ASTM) classification scheme, can also be used in an arson event. Despite the potential to be used as ILs, little is known regarding the recovery of these compounds. Previous thesis projects from the Biomedical Forensic Sciences program at Boston University School of Medicine explored and optimized the use of zeolites in recovering low molecular weight oxygenated ignitable liquids. An isothermal gas chromatography/mass spectrometry (GC/MS) method was also developed to detect these oxygenated ILs. The results from these projects show that zeolites have the potential to be used in forensic casework. Inspired by previous publications and thesis research, the goal of this project was to first develop a reference library on substrate contribution from oxygenates (e.g. ethanol, isopropanol and acetone) present in commercial products using the isothermal GC/MS methods. The development of this reference library included a specific interest in wood treatment products, considering wood is one of the most commonly submitted fire debris materials. The second stage involved an attempt at evaluating extraction efficiencies of activated charcoal strip and zeolites. The results of this project suggested that automotive and food products examined contained only acetone and ethanol respectively, while the variety of oxygenates found in household and personal care products indicated further analysis of additional products in these categories would be beneficial. Moreover, the results also reaffirmed zeolites' role in recovering oxygenated ILs in a controlled testing environment using KimWipes as a non-contributing substrate. However, the instrumental method required some modifications, as there was partial separation between ethanol and acetone. The results from applying products onto wooden blocks suggested that activated charcoal strips recovered more oxygenates than zeolites. This unexpected result prompted an investigation into the existing extraction parameters. The investigation suggested that the wooden blocks themselves were responsible for the unexpected recovery results, and future studies would be needed to understand if this recovery was substrate-specific.

L’utilisation de la biomasse végétale, que ce soit à des fins énergétiques, papetières ou valorisation dans le domaine des biomatériaux via des filières de biorafineries, nécessite la séparation des différents copolymères qui la composent par des méthodes physique et/ou chimique. Par exemple, les méthodes classiques utilisées pour extraire la cellulose mettent en jeu des réactions acido-basiques et provoquent des modifications de la structure des lignines à cause des réactions de recondensation, de déalkylation et de déshydratation. L’exploitation des lignines dans le domaine des matériaux est limitée par plusieurs facteurs notamment leur faible solubilité dans les solvants usuels, leur poids moléculaire élevé et leur faible nombre de phénols libres à l’origine de leur réactivité chimique. Ce projet s’inscrit dans un contexte de valorisation des lignines industrielles en tenant compte la structure chimique spécifique de chaque type de lignine Son objectif consiste à développer de nouvelles stratégies permettant la rupture des liaisons les plus labiles sur la chaine propyle des sous unités phénylpropanoïdes puis leur fonctionnalisation en optimisant la formation d’éthers d’énols ou en permettant leur rupture directe en évitant au maximum les réactions de recondensation en utilisant les liquides ioniques comme milieu réactionnel. Un focus particulier sera fait sur la fonctionnalisation possible des éthers d’énols conduisant à une dépolymérisation sélective des lignines papetières qui en contiennent un taux non négligeable. Selon les lignines industrielles, ces méthodes devraient permettre d’obtenir des oligomères de plus faible masse, d’augmenter également la fraction phénolique et d’améliorer la solubilité des lignines transformées ainsi que leurs propriétés antioxydantes. / The ability to use plant biomass in energy, paper industry or valorization in the field of biomaterials via biorefineries, requires the separation of the various copolymers by physical or chemical methods. For exemple, the classic methods used to extract the cellulose involve acido-basic reactions and cause modifications of the structure of lignins because of recondensation, dealkylation and dehydration reactions. The exploitation of lignins in the field of materials is limited by several factors as their low solubility in usual solvents, their high molecular weight and low number of free phenol fonctions. This project joins in a context of valuation of the industrial lignins by taking into account the specific chemical structure of every type of lignin. Its obvective consists in developing new strategies to cleave weak bonds on the propyl chain of phenylpropan units, then their fonctionnalization by optimizing the formation of enol ethers or their direct cleavage by avoiding the reactions of recondensation by using ionic liquids as reaction medium. A particular focus will be made on the possible fonctionnalization of enol ethers for a selective depolymerization of industrial lignins who contain a not insignificant rate. According to the structur of lignins, these methods should allow to obtain oligomers with low molecular weight, to increase also the phenolic fraction and improve the solubility of the transformed lignins as well as their antioxidant properties.

京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第18487号 / 地環博第121号 / 新制||地環||25(附属図書館) / 31365 / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)教授 勝見 武, 准教授 田中 周平, 准教授 乾 徹 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19011号 / 工博第4053号 / 新制||工||1624(附属図書館) / 31962 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 赤木 和夫, 教授 秋吉 一成, 教授 金谷 利治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

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Predicting the dissolution rates of immiscible contaminants in groundwater is crucial for developing environmental remediation strategies, but quantitative modeling efforts are inherently subject to multiple uncertainties. These include unknown residual amounts of non-aqueous phase liquids (NAPL) and source zone dimensions, inconsistent historical monitoring of contaminant mass discharge, and the mathematical simulation of field-scale mass transfer processes. Effective methods for simulating NAPL dissolution must therefore be able to assimilate a variety of data through physical and scalable mass transfer parameters to quantify and reduce site-specific uncertainties. This investigation coupled upscaled and numerical mass transfer modeling with uncertainty analyses to understand and develop data-assimilation and parameter-scaling methods for characterizing NAPL source zones and predicting depletion timeframes. Parameters of key interest regulating kinetic NAPL persistence and contaminant fluxes are residual mass and saturation, but neither can be measured directly at field sites. However, monitoring and characterization measurements can constrain source zone dimensions, where NAPL mass is distributed. This work evaluated the worth of source zone delineation and dissolution monitoring for estimating NAPL mass and mass transfer coefficients at multiple scales of spatial resolution. Mass transfer processes in controlled laboratory and field experiments were analyzed by simulating monitored dissolved-phase concentrations through the parameterization of explicit and lumped system properties in volume-averaged (VA) and numerical models of NAPL dissolution, respectively. Both methods were coupled with uncertainty analysis tools to investigate the relationship between data availability and model design for accurately constraining system parameters and predictions. The modeling approaches were also combined for reproducing experimental bulk effluent rates in discretized domains, explicitly parameterizing mass transfer coefficients at multiple grid scales. Research findings linked dissolved-phase monitoring signatures to model estimates of NAPL persistence, supported by source zone delineation data. The accurate characterization of source zone properties and kinetic dissolution rates, governing NAPL longevity, was achieved by adjusting model parameterization complexity to data availability. While multistage effluent rates accurately constrained explicit-process parameters in VA models, spatially-varying lumped-process parameters estimated from late dissolution stages also constrained unbiased predictions of NAPL depletion. Advantages of the numerical method included the simultaneous assimilation of bulk and high-resolution monitoring data for characterizing the distribution of residual NAPL mass and dissolution rates, whereas the VA method predicted source dissipation timeframes from delineation data alone. Additionally, comparative modeling analyses resulted in a methodology for scaling VA mass transfer coefficients to simulate NAPL dissolution and longevity at multiple grid resolutions. This research suggests feasibility in empirical constraining of lumped-process parameters by applying VA concepts to numerical mass transfer and transport models, enabling the assimilation of monitoring and source delineation data to reduce site-specific uncertainties. / Doctor of Philosophy / Predicting the dissolution rates of immiscible contaminants in groundwater is crucial for developing environmental restoration strategies, but quantitative modeling efforts are inherently subject to multiple uncertainties. These include unknown mass and dimensions of contaminant source zones, inconsistent groundwater monitoring, and the mathematical simulation of physical processes controlling dissolution rates at field scales. Effective simulation methods must therefore be able to leverage a variety of data through rate-limiting parameters suitable for quantifying and reducing uncertainties at contaminated sites. This investigation integrated mathematical modeling with uncertainty analyses to understand and develop data-driven approaches for characterizing contaminant source zones and predicting dissolution rates at multiple measurement scales. Parameters of key interest regulating the lifespan of source zones are the distribution and amount of residual contaminant mass, which cannot be measured directly at field sites. However, monitoring and site characterization measurements can constrain source zone dimensions, where contaminant mass is distributed. This work evaluated the worth of source zone delineation and groundwater monitoring for estimating contaminant mass and dissolution rates at multiple measurement scales. Rate-limiting processes in controlled laboratory and field experiments were analyzed by simulating monitored groundwater concentrations through the explicit and lumped representation of system properties in volume-averaged (VA) and numerical models of contaminant dissolution, respectively. Both methods were coupled with uncertainty analysis tools to investigate the relationship between data availability and model design for accurately constraining system parameters and predictions. The approaches were also combined for predicting average contaminant concentrations at multiple scales of spatial resolution. Research findings linked groundwater monitoring profiles to model estimates of contaminant persistence, supported by source zone delineation data. The accurate characterization of source zone properties and contaminant dissolution rates was achieved by adjusting model complexity to data availability. While monitoring profiles indicating multi-rate contaminant dissolution accurately constrained explicit-process parameters in VA models, spatially-varying lumped parameters estimated from late dissolution stages also constrained unbiased predictions of source mass depletion. Advantages of the numerical method included the simultaneous utilization of average and spatially-detailed monitoring data for characterizing the distribution of contaminant mass and dissolution rates, whereas the VA method predicted source longevity timeframes from delineation data alone. Additionally, comparative modeling analyses resulted in a methodology for scaling estimable VA parameters to predict contaminant dissolution rates at multiple scales of spatial resolution. This research suggests feasibility in empirical constraining of lumped parameters by applying VA concepts to numerical models, enabling a comprehensive data-driven methodology to quantify environmental risk and support groundwater cleanup designs.

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