In this thesis we focus on the modelling and simulation of organic electronic devices, investigating their structural and electronic properties. Organic devices have attracted great interest for their innovative properties, but their functioning still represent a theoretical and technological challenge. They are composed by one or more organic materials depending on the particular application. The morphology of organic devices in the single phase or at the interface is known to strongly determine mobility and efficiency of the devices. The structural disorder is studied through molecular dynamics (MD) simulations. Marcus formula is used to calculate the hopping rate of the charge carriers and the model developed is tested by simulations in a Kinetic Monte Carlo scheme. The dependence of the transfer integrals on the relative molecular orientation is achieved through a weighted Mulliken formula or through a dimer projection approach using the semi-empirical Hartree Fock method ZINDO. Electrostatic effects, have been included through atomic charges and atomic polarizabilities, calculated at the B3LYP level of theory. The inclusion of electrostatic effects has been shown (through simulations in 4PV and C60) to be crucial to obtain a good qualitative agreement with experiments, for both mobility field and temperature dependence in the single phase. In particular the external reorganization energy, calculated through the polarization of the environment, has been shown to have a great impact on the conduction, shifting the inverse Marcus region and helping CT state separation at the interface (between C60 and anthracene).

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Poly- and perfluoroalkyl substances (PFAS) are a chemical class of global concern because of their persistence, toxicity and widespread presence in the environment. This work aimed to develop a robust and reliable method to analyse perfluorohexane sulfonic acid (PFHxS), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), as well as the neutral volatile PFOS precursors, namely perfluorooctane sulfonamides and perfluorooctane sulfonamidoethanols (FOSAs/FOSEs). Because these compounds can be distributed globally through atmospheric long-range transport, air sampling materials, such as polyurethane foam (PUF) or styrene-divinylbenzene resin (XAD) sorbents are used to capture them. Parameters optimised were extraction solvents, solid phase extraction (SPE) as clean-up and instrumental parameters of the utilised ultra-performance liquid chromatograph tandem mass spectrometer (UPLC-MS/MS) with electron spray ionisation (ESI). The resulting method consisted of Soxhlet extraction with methyl tert-butyl ether (MTBE), and subsequently methanol, followed by a weak anion exchange (WAX) SPE clean-up and injection onto a LC-ESI-MS/MS system, quantification by using isotope dilution. This method was applied for analysis of samples from active (AAS) and passive air samplers (PAS), as well as snow, that were collected in Sweden during the project. Additionally, PUF samples exposed for three months in Örebro in 2017 and several PAS/PUFs spanning two years and sampled as part of the Global Monitoring Plan (GMP), were analysed. The performance of the method was evaluated and gave median recoveries of internal standard of all analytes in blanks of all sample batches ranging from 42 % to 105 %, while median recoveries in real samples were below 20 %. Because of the poor recoveries in samples, only concentrations of ionic PFAS in PAS/PUFs and snow samples from Örebro could be determined. Mean concentrations in PUF samples form Örebro from 2017 were between 30 and 40 pg/m³ and between 6 and 19 pg/m³ for L-PFOS and PFOA, respectively. Lowest concentrations were detected for PFHxS. Concentrations of L-PFOS and PFOA detected in snow in Örebro during the project were roughly one order of magnitude higher compared to the Arctic and about two orders of magnitude lower than in urban China. Overall, more data and a more reliable analytical method is needed to draw conclusions about seasonal or regional variability or correlations between atmospheric PFAS concentrations and wet precipitation. To develop a reliable analytical method for the analysis of PUFs, more real samples need to be available to accurately assess efficiency of clean-ups.

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In this study, the total as well as the water-soluble and bioaccessible fractions of lithium in wheat, durum and barley flour were evaluated together with the isotope ratio. Lithium was determined by inductively coupled plasma – mass spectrometry (ICP-MS). The total lithium content was determined after an open-vessel digestion in HNO3. The water-soluble fraction was evaluated by extraction with deionized water. The bioaccessibility was determined in vitro under simulated stomach digestion conditions. The total lithium content in wheat ranged from 0.91 ng/g to 7.8 ng/g, in durum flour from 1.7 ng/g to 5.2 ng/g and for barley flour from 2.0 ng/g to 6.0 ng/g. For the water-soluble fraction, the ranges were for wheat flour 0.33 ng/g to 4.8 ng/g, for durum flour 0.83 ng/g to 2.5 ng/g and for barley flour 0.81 ng/g to 3.3 ng/g. The bioaccessible lithium content ranges in wheat flour from 0.38 ng/g to 5.3 ng/g, in durum flour from 0.98 ng/g to 1.9 ng/g and in barley flour from 1.3 ng/g to 3.1 ng/g. The water and bioaccessible fractions of the majority of the barley and durum flour samples had an isotope ratio differing statistically significantly from the natural ratio (p<0.05) which indicates enrichment of the heavier isotope. Additionally, speciation of protein bound lithium in water and simulated stomach digestion extracts from respective flours were studied. Extracts from the respective flour types were chromatographically separated and fractionated with an ammonium nitrate buffer on a (size-exclusion-chromatography) SEC-column. Thirty fractions were collected, and their lithium contents were determined by ICP-MS. Lithium was mostly eluted in fraction 14, which indicates that most of the available lithium was protein-bound.

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Ce manuscrit détaille différentes méthodes de synthèse des sulfoxydes vinyliques ainsi que leurs utilisations dans une réaction d'addition conjuguée intramoléculaire pour obtenir des 1,3-diols syn. Ces derniers sont employés pour la synthèse de précurseurs d'analogues de nucléosides. Dans le premier chapitre, nous montrerons différents aspects importants de la chimie des nucléosides et de leurs analogues; nous présenterons leur mécanisme d'action, ainsi que des médicaments à structure nucléosidique utilisés pour traiter différentes maladies virales. Par la suite, nous décrirons quelques méthodes de synthèses décrites dans la littérature pour ce type de molécules, ainsi que quelques exemples pour la synthèse des motifs 1,3-diols syn, sans vouloir être exhaustif ni trop entrer dans les détails. Le deuxième chapitre présente les différentes méthodes de synthèse que nous avons utilisées pour la synthèse des sulfoxydes vinyliques. Ces derniers sont les précurseurs de la réaction d'addition conjuguée intramoléculaire que nous utilisons pour la mise en place du motif 1,3-diol syn, cette réaction ainsi que les résultats obtenus seront discutés dans le chapitre 3. Finalement, nous exposerons les résultats obtenus pour la réaction de Pummerer et la réaction de cyclisation en milieu acide, qui nous a permis d'obtenir les analogues du 3-désoxyribose et ses analogues.