The repair of automobiles is a critical aspect in vehicle ownership and is potential source of volatile toxic compounds being brought into a home when repairs are conducted in an attached garage. The goal of this study was to assess the impact of the repair of automobiles in an attached garage on the exposure of the home mechanic and degradation of indoor air. Five common automotive tasks were performed in two garages with the garage door either opened 30.5 centimeters (n=5) or closed (n=4). The exposure to the home mechanic, the behavior of contaminants within the garage, and infiltration of contaminants in the home were the determinants of interest. Integrative sampling incorporating charcoal sorbent sampling tubes analyzed by gas chromatography and directs reading photo ionization detectors were used to assess exposure. The tasks with the greatest contributions to the home mechanic’s exposure were found to be brake pad replacement and oil change; these generated 95th percentile concentrations of 51.2 ppm and 12.8 ppm, respectively, with the garage door closed. In contrast, the tasks of refueling and shock replacement had 95th percentile contributions of 0.85 ppm and 2.99 ppm, respectively, in the closed garage. Equations were fitted to the aggregated concentrations during decay to estimate general ventilation (Q/V) in a closed garage. The contaminants within the garage were not found to infiltrate into the home as the average concentrations within the home never exceeded 1 ppm. It was found that automotive repair work in a closed garage may constitute up to 18% of threshold limit value of toluene over a 105 minute exposure at home. Automotive repair inside an attached garage has the potential to make a significant contribution to a mechanic’s daily exposure and should be incorporated into occupational exposure assessments of volatile organic compounds.

Le développement du concept de chimie analytique « verte » représente l’une des préoccupations majeures du tout début du 21ème siècle ; elle a amené les différents acteurs du domaine à s’interroger sur le bien-fondé du développement de méthodes ayant un impact sur l’environnement et sur l’homme. Dans le domaine de l’analyse des lipides, les séparations par classe nécessitent de travailler sur une très large gamme de polarité, conséquence directe de la diversité des structures et des solubilités mises en jeu. La chromatographie en phase normale (NPLC) permet de réaliser l’élution des composés par ordre de polarité croissante. La mise en solution des classes lipidiques nécessite le recours à des mélanges de solvants incluant le chloroforme, le n-heptane, dichlorométhane. Les solvants organiques classiquement utilisés en NPLC, bien que performants, soulèvent aussi de nombreux problèmes liés à leur toxicité pour l'homme et l'environnement, leur volatilité, ou encore leur origine quand ils sont issus des hydrocarbures fossiles. Une des voies envisagée est la substitution de ces solvants par des solvants alternatifs, tels ceux proposés par les différents acteurs de la chimie verte. L'intérêt suscité par ces solvants est prometteur en termes de réduction de l'utilisation de solvants avec un impact significatif sur l'environnement. Les propriétés de la chromatographie en phase dioxyde de carbone supercritique sont semblables à la NPLC et offrent également une alternative verte à cette méthode. Ce travail a mis en évidence que des méthodes de séparation pourraient être développées avec des solvants alternatifs au n-heptane, au méthanol et au chloroforme. Leur utilisation est compatible avec la chromatographie liquide et la chromatographie supercritique et offre une meilleure sélectivité en termes de séparation des classes de lipides. La compatibilité de solvants alternatifs avec ELSD et la spectrométrie de masse a également été évaluée, ce qui a montré que l'absence de pureté suffisante pourrait être un problème. Cependant, ce problème a également été observé avec l'utilisation de solvants commerciaux, qui présentaient des impuretés telles que des acides gras, des polymères et des antioxydants. / Green analytical chemistry development represents one of the main issues of the 21th century. Many investigators in analytical chemistry are actually involved in the development of well-established analytical methods that prevent irreversible damage to humans and environment. In the domain of lipid analysis, structural diversity as well as difference in solubility of these compounds is leading to work with a very large polarity range to separate lipids by classes. The normal-phase liquid chromatography (NPLC) allows realising the elution of compounds in order of increasing polarity. The solubilisation of lipid classes requires the use of a mixture of several solvents, among them chloroform, n-heptane, dichloromethane. Moreover, organic solvents traditionally used in NPLC, although well performing are raising different problems due to their original source, i.e. fossil hydrocarbons, volatility and toxicity for humans and environment. One of the ways to avoid such solvents is the substitution with alternative solvents, as proposed by various players in green chemistry. The interest raised by these solvents, is promising in terms of reduction of solvent use with a significant environmental impact. The properties of supercritical fluid chromatography using CO₂ are similar to NPLC and also offer a green alternative to this method. This work has highlighted that separation methods could be developed with alternative solvents to n-heptane, methanol and chloroform. Their use is compatible with liquid and supercritical chromatography and offer better selectivity in terms of separation of lipid classes. The compatibility of alternative solvents with ELSD and mass spectrometry was also evaluated, which showed that the unavailability of sufficient purity could be an issue. However, this problem was also observed with the use of commercial solvents, which presented impurities such as fatty acids, polymers and antioxidants.

En la presente memoria se describe el uso de líquidos eutécticos sostenibles (DESs en inglés) como medios de reacción, empleando diferentes catalizadores metálicos para llevar a cabo la síntesis de compuestos orgánicos de interés en química orgánica. En el Primer Capítulo se detalla el uso de un catalizador heterogéneo de cobre soportado sobre magnetita en el acoplamiento cruzado deshidrogenante de tetrahidroisoquinolinas en mezclas eutécticas. En el Segundo Capítulo se pormenoriza sobre la síntesis de un complejo tipo pinza de paladio y su empleo en la reacción de acoplamiento cruzado de Hiyama, tanto en mezclas eutécticas como en glicerol, como medios sostenibles de reacción. Asimismo, y con el fin de mejorar la compatibilidad de los catalizadores de paladio en estos líquidos eutécticos, se detalla el diseño y la síntesis de fosfinas catiónicas, las cuales han probado su efectividad como ligandos de paladio en reacciones típicas de acoplamiento cruzado (Suzuki, Heck y Sonogashira) en diferentes mezclas eutécticas. Finalmente, en el Tercer Capítulo se describen reacciones multicomponente de acoplamiento cruzado para la formación de enlaces C-S. Por un lado, se ha desarrollado una metodología para la inserción de SO2 catalizada por paladio a partir de ácidos borónicos y metabisulfito de sodio. Por otro lado, una variante de la metodología anterior permitió la síntesis de sulfonamidas sustituyendo los ácidos borónicos por compuestos de triarilbismuto y nitrocompuestos bajo catálsis de cobre. En este último caso, una nueva mezcla eutéctica ha sido descrita y caracterizada, tanto físco-química como biológicamente.

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Organic solar cells (OSCs) have gained considerable attention from the scientific community in recent decades due to their remarkable power conversion efficiency (PCE), flexibility, and cost-effectiveness in producing large-area batteries. Despite the ongoing research efforts that have led to a PCE exceeding 19% for single-junction OSCs and surpassing 20% for multi-junction OSCs, the commercialization of these devices is hampered by their poor stability, reliance on specific additives, and the use of toxic solvents. To address these shortcomings, this study focuses on investigating the 3 * 3 thermosets matrix to facilitate the selection of precursors for in-situ crosslinking thermosets. Furthermore, in this study, we fabricated the devices using green solvents to narrow the gap between PCE and stability under environmentally friendly conditions. We utilized PTQ10: BTP-BO4Cl as the model system and employed tetrahydrofuran (THF) as an eco-friendly solvent. The research focused on examining the thermoset's glass transition temperature (Tg), modulus and morphology properties. The resulting cross-linked thermoset network has high-density hydrogen bonding and network grids, which helps to stabilize the morphology of the active layer. The findings indicated that selecting a thermoset with high Tg, high modulus (4-8 MPa), and good uniformity as an in-situ crosslinking additive would be beneficial. These results can guide the selection of universal in-situ crosslinking thermosets and aid in improving the stability of various organic electronic devices.

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