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Over the last few years, the combination of ion mobility with mass spectrometry has gained interest in a variety of analytical fields, including trace pollutants analysis in complex matrices such as environmental and food samples. This technique separates ions according to their ion mobility in the gas phase (diffusion speed under the influence of an electrical field in a pressurized cell) and provides an additional dimension to the traditional GC/LC-MS systems, a higher selectivity and a noise reduction which lead to signal-to-noise ratios improvement. Collision cross-section, which is related to the charge state, size, and shape of the ion can be derived from the measurement of ion mobility. Trapped Ion Mobility Spectrometer (TIMS) was recently introduced and offers a more compact design with an improved ion mobility resolving power (up to 400) compared to other commercially available IM instruments. As a recent technique, it still needs to make its proof in analytical chemistry while coupled to gas chromatography mass spectrometry using an APCI source. In this master thesis, we investigated the potential of the APGC-TIMS-MS coupling applied to small persistent organic pollutants (POPs) like dioxins and polychlorobiphenyl derivatives (PCBs). We found that a complete mobility separation of dioxins and PCB congeners was achievable in the CCS frame according to their chlorination degree, while non baseline separation was usually reached for isomeric congeners. We also highlighted issues with the IMS calibration in the present coupling and proposed different methods for on-line calibration. We produced data supporting that the calibration was truly dependent on the source conditions and that internal and external calibrations both fail to provide absolute and accurate CCS. Calibration based on the chemical background from the GC column (polysiloxanes), shows an interesting potential in this regard.

Mass spectrometry --- Ion mobility --- Trapped ion mobility spectrometry --- Dioxin --- Furan --- PCB --- Pollutant --- Environment --- Food --- Feed --- Physique, chimie, mathématiques & sciences de la terre > Chimie

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This thesis deals with the problem of ion confinement in thermonuclear fusion devices. It is a topic of general interest, as it helps to understand via numerical simulations the ion confinement properties in complex geometries, in order to predict their behavior and maximize the performance of future fusion reactors. The main work carried out in this thesis is the improvement and exploitation of an existing simulation code called ISDEP.  This code solves the so-called ion collisional transport in arbitrary plasma geometry, improving in this sense other existing codes. Additionally, it presents outstanding portability and scalability in distributed computing architectures, such as Grid or Volunteer Computing. The main physical results can be divided into two blocks. First, the study of 3D ion transport in ITER is presented. ITER is the largest fusion reactor (under construction) and most of the simulations so far assume the axis-symmetry of the device. Unfortunately, this symmetry is only an approximation because of the discrete number of magnetic coils used. ISDEP has shown, using a simple model of the 3D magnetic field, how the ion confinement is affected by this symmetry breaking. Secondly, ISDEP has been applied successfully to the study of fast ion dynamics in fusion plasmas. The fast ions, with energies much larger than the thermal energy, are a product of the device’s heating system. Thus, a numerical predictive tool can be used to improve the heating efficiency. ISDEP has been combined with the FAFNER2 code to study such ions in stellarator (TJ-II, LHD) and tokamak (ITER) geometries. It has also been validated by experimental results. In particular, comparisons with the CNPA diagnostic in the TJ-II stellarator are remarkable.

Physics --- Physical Sciences & Mathematics --- Electricity & Magnetism --- Ion mobility spectroscopy. --- Ions. --- Chromatography, Plasma --- IMS (Spectrum analysis) --- Ion mobility spectrometry --- Plasma chromatography --- Spectrometry, Ion mobility --- Spectroscopy, Ion mobility --- Physics. --- Nuclear energy. --- Nuclear fusion. --- Plasma (Ionized gases). --- Plasma Physics. --- Numerical and Computational Physics. --- Nuclear Energy. --- Nuclear Fusion. --- Intermediates (Chemistry) --- Matter --- Solution (Chemistry) --- Electrolysis --- Electrons --- Spectrum analysis --- Properties --- Numerical and Computational Physics, Simulation. --- Fusion, Nuclear --- Fusion reactions --- Fusion --- Nuclear reactions --- Atomic energy --- Atomic power --- Energy, Atomic --- Energy, Nuclear --- Nuclear power --- Power, Atomic --- Power, Nuclear --- Force and energy --- Nuclear physics --- Power resources --- Nuclear engineering --- Nuclear facilities --- Nuclear power plants --- Natural philosophy --- Philosophy, Natural --- Physical sciences --- Dynamics --- Gaseous discharge --- Gaseous plasma --- Magnetoplasma --- Ionized gases

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Metabolomics is increasingly being used to explore the dynamic responses of living systems in biochemical research. The complexity of the metabolome is outstanding, requiring the use of complementary analytical platforms and methods for its quantitative or qualitative profiling. In alignment with the selected analytical approach and the study aim, sample collection and preparation are critical steps that must be carefully selected and optimized to generate high-quality metabolomic data. This book showcases some of the most recent developments in the field of sample preparation for metabolomics studies. Novel technologies presented include electromembrane extraction of polar metabolites from plasma samples and guidelines for the preparation of biospecimens for the analysis with high-resolution μ magic-angle spinning nuclear magnetic resonance (HR-μMAS NMR). In the following chapters, the spotlight is on sample preparation approaches that have been optimized for diverse bioanalytical applications, including the analysis of cell lines, bacteria, single spheroids, extracellular vesicles, human milk, plant natural products and forest trees.

Medicine --- metabolomics --- sample preparation --- hydrophilic interaction liquid chromatography --- ion mobility spectrometry --- high resolution mass spectrometry --- design of experiments --- AMOPLS --- metabonomics --- metabolic profiling --- NMR --- nuclear magnetic resonance spectroscopy --- cell line --- human cell line --- MiaPaCa-2 --- Panc-1 --- AsPC-1 --- extracellular vesicles --- exosomes --- microvesicles --- biomarkers --- diagnostics --- metabolic pathways --- plant metabolomics --- forestry --- trees --- mass spectrometry --- metabolite extraction --- GC-MS --- LC-MS --- metadata standardization --- databases --- multicellular tumor spheroids --- metallodrugs --- oxaliplatin --- KP1339 --- method development --- IT-139 --- 20% FCS --- harvesting --- extraction --- metabolites --- normalization --- electromembrane extraction --- cardiovascular disease --- multi-segment injection --- capillary electrophoresis–mass spectrometry --- liquid chromatography–mass spectrometry --- plant natural products --- drug discovery --- liquid chromatography --- gas chromatography --- human milk --- metabolome --- sampling --- liquid chromatography–mass spectrometry (LC-MS) --- nuclear magnetic resonance (NMR) --- gas chromatography–mass spectrometry (GC-MS) --- capillary electrophoresis—mass spectrometry (CE-MS) --- high-resolution magic angle spinning --- microscopic samples --- lipidomics --- LC-MS/MS --- human plasma