Dissertationen zum Thema „Phase quantification“
Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an
Machen Sie sich mit Top-50 Dissertationen für die Forschung zum Thema "Phase quantification" bekannt.
Neben jedem Werk im Literaturverzeichnis ist die Option "Zur Bibliographie hinzufügen" verfügbar. Nutzen Sie sie, wird Ihre bibliographische Angabe des gewählten Werkes nach der nötigen Zitierweise (APA, MLA, Harvard, Chicago, Vancouver usw.) automatisch gestaltet.
Sie können auch den vollen Text der wissenschaftlichen Publikation im PDF-Format herunterladen und eine Online-Annotation der Arbeit lesen, wenn die relevanten Parameter in den Metadaten verfügbar sind.
Sehen Sie die Dissertationen für verschiedene Spezialgebieten durch und erstellen Sie Ihre Bibliographie auf korrekte Weise.
Butler, Jonny. „Phase structure, phrase structure, and quantification“. Thesis, University of York, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415175.
Der volle Inhalt der QuelleGouverneur, Yves. „Phase de Berry et quantification de skyrmions“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0002/MQ33663.pdf.
Der volle Inhalt der QuelleBeese, Allison M. „Quantification of phase transformation in stainless steel 301LN sheets“. Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44870.
Der volle Inhalt der QuelleIncludes bibliographical references (p. 101-102).
This thesis investigates the large deformation behavior of stainless steel 301LN cold-rolled sheets which is largely governed by the initial anisotropy combined with the phase transformation during deformation. Stainless steel offers high strength with relatively high ductility as compared with other structural steels. The effect of initial anisotropy on the strength in different material directions is studied in order to predict forming and crash response of vehicle components. It is observed that loading in the material rolling direction results in increased strength in the cross direction, however loading in the material cross-rolling direction results in decreased strength in the rolling direction. The mechanism responsible for the above cross-hardening is complex and requires investigation of the microstructural evolution of the sheets. The austenitic stainless steel studied is comprised of only austenite when in bulk form. However, the process of cold-rolling the bulk material into sheets results in strain-induced martensitic phase transformation. Additional straining of the material leads to even more transformation of austenite to martensite. Because martensite is a harder phase than austenite, micromechanical arguments suggest that the amount of martensite has an effect on the plasticity and eventual fracture of this material. In this thesis, the martensitic evolution as a function of material direction and strain level is measured using three different techniques: X-ray diffraction, microscopy, and magnetic induction. The first two methods require interrupted tests, while using a Feritscope allows for in-situ measurement of the martensite content. However, the Feritscope must be calibrated by another measurement method.
(cont.) Observations of the measurements from each of the three methods confirm that the output of the Feritscope, Ferrite Number, is proportional to the martensite content. Therefore in-situ tests employing the Feritscope will allow for monitoring of the martensite content with evolution of stress and strain. From experiments described here, a directional dependence on martensite content is observed. The results from this study can be used to formulate an anisotropic martensite transformation kinetics law to describe the evolution of martensite content as a function of material anisotropy, stress state, and strain state.
by Allison M. Beese.
S.M.
Chatzimavroudis, George P. „Quantification of valvular regurgitation with magnetic resonance phase velocity mapping“. Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/11808.
Der volle Inhalt der QuelleWallin, Ashley Kay. „Renal Arterial Blood Flow Quantification by Breath-held Phase-velocity Encoded MRI“. Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4982.
Der volle Inhalt der QuelleEngberg, Jonas. „Deep morphological quantification and clustering of brain cancer cells using phase-contrast imaging“. Thesis, Uppsala universitet, Avdelningen för visuell information och interaktion, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-454959.
Der volle Inhalt der QuelleLin, Hung-Yu. „REAL-TIME FLOW QUANTIFICATION TECHNIQUES IN CARDIOVASCULAR MRI APPLICATIONS“. The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1238594589.
Der volle Inhalt der QuelleMilet, Sylvain F. „Visualization and quantification of left heart blood flow by phase encoding magnetic resonance imaging“. Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/16056.
Der volle Inhalt der QuelleROTEM, RANY. „Development of Reliable Experimental Models for the Study of the Biological Behavior of Drug Nanocarriers“. Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241245.
Der volle Inhalt der QuelleThe curative effectiveness of current and new drugs is often limited by poor pharmacokinetics in-vivo. The use of nanoparticles as drug carriers seems promising in solving this problem. In this work we aimed to further explore and improve common drug delivery components and techniques. Starting with the synthesis of nanoparticles with a controlled number of molecular recognition ligands, we used bulky ligands and gel separation to obtain nanoparticles with a discrete number of chemical functional groups, used later to conjugate the same number of molecular recognition ligands. These nanoparticles later showed substantial difference in the in-vivo behavior. A second project focused on the in-depth characterization of the relationship between hydrophobic inorganic nanoparticles and the polymer surfactants used to enable their water dispersibility, as well enabling their functionalization. This investigation was done through separate quantification of polymer and inorganic nanoparticles and assessment of stability. Our results showed that the removal of excess polymer from such systems can result in loss of colloidal stability. A third project was aimed to describe the mechanism of polymeric nanoparticle’s endosomal escape and provide a platform for qualitative investigation and enhancement of this process. This goal was accomplished through two complementary in-vitro experiments testing two proposed mechanisms of endosomal escape. These results raised a key consideration when matching a particle capable of endosomal escape to a specific cell type as well as methods reduce interaction with serum proteins. A fourth project focused on developing an assay to quantify cytosolic delivery of nanoparticles and theoretically assessed the possibility of using fluorescence resonance energy transfer (FRET) - which was found to be not practical in this case - as well as implementing a pro-fluorophore to generate a measurable signal. Our preliminary results indicate this method might indeed be useful for this purpose in the future.
Deroche, Annabelle. „Optimisation de la limite de quantification d'une méthode chromatographique en phase gazeuse couplée à une détection par capture d'électrons : développement et application au dosage d'un antiandrogène dans le plasma humain“. Paris 5, 1997. http://www.theses.fr/1997PA05P224.
Der volle Inhalt der QuelleZhao, Xuandong. „A study of Quantification of Aortic Compliance in Mice using Radial Acquisition Phase Contrast MRI“. University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1273001921.
Der volle Inhalt der QuelleCorazzola, Alessandro. „Quantification of condensed tannins in red wines by Fourier transform mid-infrared spectroscopy (FTIR)“. Master's thesis, ISA/UL, 2012. http://hdl.handle.net/10400.5/8609.
Der volle Inhalt der QuelleGrape-derived condensed tannins, also known as proanthocyanidins, are critical quality components for red wines. They have been subject of numerous studies in order to find a fast and reliable methodology for their quantification. In this work it has been tested the method using Fourier transform mid-infrared (FTIR) and chemometrics to quantify the amount of condensed tannins present in 88 different red wines, with the reference method of precipitation with methylcellulose. As well it has been provided a single laboratory validation of the method of fractionation of condensed tannins by reverse phase and quantification by reaction with vanillin. The models developed for the FTIR spectroscopy were not enough robust for the estimation of total condensed tannins, with low values of coefficient of determination and low RPD values (R2 cross-validation: 0,76 and RPD cross-validation: 1,86). Validation of the fractionation method showed good performance in precision, with values of coefficient of variance for the three fractions FIII, FII and FI respectively of 5,2%; 11,4% and 11,6% and values of reproducibility of 168,1; 32,9 and 3,4 mg/L of epicatechin equivalents, but it was not possible to perform effective recovery studies
Dyverfeldt, Petter. „Extending MRI to the Quantification of Turbulence Intensity“. Doctoral thesis, Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-52561.
Der volle Inhalt der QuelleGoldstein, Lucas. „Three-dimensional visualization and quantification of residual non-aqueous phase liquids using x-ray computed tomography“. Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81334.
Der volle Inhalt der QuelleIn this study, experiments were conducted to demonstrate the capabilities and limitations of X-ray Computed Tomography (CT) to non-destructively quantify contaminants in soil columns.
Wang, Dewei. „Uncertainty Quantification and Accuracy Improvement of the Double-Sensor Conductivity Probe for Two-Phase Flow Measurement“. Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/103074.
Der volle Inhalt der QuelleDoctor of Philosophy
The double-sensor conductivity probe is one widely used technique for measuring local time-averaged parameters in two-phase flows. Although a number of studies have been carried out in the past, a good understanding of the uncertainty of this technique is still lacking. This paper aims to address this gap by performing a systematic and comprehensive study on the measurement uncertainty of the probe. Three types of uncertainties are analyzed: that of measurands, of the model input parameters, and of the mathematical models. A better understanding of the uncertainty of the double-sensor conductivity probe has been obtained. Considering the unique measuring principles and advantages of multiple advanced techniques, a method is developed to integrate these techniques with the double-sensor conductivity probe to further improve the accuracy of local two-phase flow measurement. It has been demonstrated that the integration method significantly improves the accuracy of probe measurements. Realizing the needs of high-resolution two-phase flow data to the further development of various two-phase flow models and validation of two-phase CFD codes, a comprehensive database of two-phase flows is acquired. The gas-phase and liquid-phase information are acquired by the new integration method and the recently developed Particle Image Velocimetry and Planar Laser Induced Fluorescence (PIV-PLIF) technique, respectively. The classical 1-D drift-flux model is re-evaluated by the newly obtained dataset. The distribution parameter model has been optimized, resulting in significant improvements in predicting both gas velocity and void fraction.
Mobile, Michael Anthony. „Quantification of Parameters in Models for Contaminant Dissolution and Desorption in Groundwater“. Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/37812.
Der volle Inhalt der QuellePh. D.
Promelle, Véronique. „Quantification de la vascularisation ophtalmique par IRM en contraste de phase : application à la pathologie du glaucome“. Thesis, Amiens, 2020. http://www.theses.fr/2020AMIE0037.
Der volle Inhalt der QuelleThe dynamics of the vascular arterial and venous supply of the eye remains poorly understood, coming mainly from studies in Doppler color imaging with very little quantitative data about venous component. The physiopathology of glaucoma is still under debate, with many ongoing investigations and hypotheses. Among them, vascular changes have been suggested to be a possible cause for the disease, but no pathophysiology model could be proposed that connect the different current hypotheses. Phase contrast magnetic resonance imaging (PC MRI) is a non-invasive MRI sequence for quantitative measurement of the vascular dynamics of a system. So far mainly used to investigate large caliber arteries, PC MRI has not yet been used to measure flows of the ophthalmic artery and vein. The objective of this work was to quantify by PC MRI the blood flow and vascular dynamics of the ophthalmic artery (OA) and the superior ophthalmic vein (SOV) in a population of healthy subjects in a first part, and in glaucoma patients in a second part. In total, 21 volunteers without ocular disease and 11 patients diagnosed with glaucoma were included. They all underwent 3 Tesla MRI examination with PC MRI sequence, in the same settings. The right and left OA and SOV were identified using anatomic sequences, to place a PC MRI acquisition plane perpendicular to their course. PC MRI series were analyzed using a dedicated software, calculating the flow for each phase of the cardiac cycle and displaying the curve of flow during cardiac cycle for each vessel. From this data the mean, maximal and minimal blood flow for each vessel were calculated. The results obtained in healthy subjects showed the feasibility and reliability of the technique. They were considered as normal reference and were later used as control. Notably, a significant pulsatility of the venous flow during the cardiac cycle was demonstrated. In glaucoma patients, this venous pulsatility was significantly lower. Also in patients our results showed a loss of the correlation between the mean flow and the maximal velocity in the OA. The flow waveform and the relationships between flow, velocity and section of the SOV suggested an impairment of the venous hemodynamics in glaucoma, which could result from capillary changes and/or from downstream pressure changes
Vo, Duyen Thuy. „Detection and Attempted Quantification of Allelopathic Chemicals in Buffelgrass (Pennisetum ciliare) Root Leachates Using Reverse Phase-HPLC“. Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/297777.
Der volle Inhalt der QuelleJonathan, Bremer Lin Weili. „Single scan MR velocity quantification in ROI by alternating velocity encoding gradient pulse polarity between phase encoding steps“. Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,2046.
Der volle Inhalt der QuelleTitle from electronic title page (viewed Feb. 17, 2009). "... in partial fulfillment of the requirement for the degree of Master in the Department of Biomedical Engineering." Discipline: Biomedical Engineering; Department/School: Medicine.
Klein, Marlène. „Identification et quantification de métabolites séléniés dans l’urine humaine“. Pau, 2010. http://www.theses.fr/2010PAUU3034.
Der volle Inhalt der QuelleThe concentration range between beneficial and toxic effects for selenium (Se) is very narrow. In order to monitor selenium intake and to improve knowledge of Se metabolism, studies on selenium species ingested and excreted are performed. This report presents the development and the optimization of speciation analysis of dissolved and volatile Se species in urine of non supplemented subjects by coupling liquid chromatography or gas chromatography to inductively coupled plasma mass spectrometry. In the case of dissolved species, solid phase extraction of the sample as sample pretreatment allowed us to confirm the presence of known selenium compounds and to highlight unknown selenium species. One of these new species was further identified by molecular mass spectrometry. The analysis of volatile selenium compounds was performed by gas chromatography coupled to ICP-MS after sample extraction by SPME. This method led to the identification of some selenium and mixed selenium/sulphur species in urine from non supplemented subjects and allowed us to define suitable storage conditions to maintain original speciation
Carlier, Julien. „Schémas aux résidus distribués et méthodes à propagation des ondes pour la simulation d’écoulements compressibles diphasiques avec transfert de chaleur et de masse“. Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLY008/document.
Der volle Inhalt der QuelleThe topic of this thesis is the numerical simulation of two-phase flows in an industrial framework. Two-phase flows modelling is a challenging domain to explore, mainly because of the complex phenomena involved, such as cavitation and other transfer processes between phases. Furthermore, these flows occur generally in complex geometries, which makes difficult the development of efficient resolution methods. The models that we consider belong to the class of diffuse interface models, and they allow an easy modelling of transfers between phases. The considered class of models includes a hierarchy of sub-models, which take into account different levels of interactions between phases. To pursue our studies, first we have compared the so-called four-equation and six-equation two-phase flow models, including the effects of mass transfer processes. We have then chosen to focus on the four-equation model. One of the main objective of our work has been to extend residual distribution schemes to this model. In the context of numerical solution methods, it is common to use the conservative form of the balance law. In fact, the solution of the equations under a non-conservative form may lead to a wrong solution to the problem. Nonetheless, solving the equations in non-conservative form may be more interesting from an industrial point of view. To this aim, we employ a recent approach, which allows us to ensure conservation while solving a non-conservative system, at the condition of knowing its conservative form. We then validate our method and apply it to problems with complex geometry. Finally, the last part of our work is dedicated to the evaluation of the validity of the considered diffuse interface model for applications to real industrial problems. By using uncertainty quantification methods, the objective is to get parameters that make our simulations the most plausible, and to target the possible extensions that can make our simulations more realistic
Carlier, Julien. „Schémas aux résidus distribués et méthodes à propagation des ondes pour la simulation d’écoulements compressibles diphasiques avec transfert de chaleur et de masse“. Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLY008.
Der volle Inhalt der QuelleThe topic of this thesis is the numerical simulation of two-phase flows in an industrial framework. Two-phase flows modelling is a challenging domain to explore, mainly because of the complex phenomena involved, such as cavitation and other transfer processes between phases. Furthermore, these flows occur generally in complex geometries, which makes difficult the development of efficient resolution methods. The models that we consider belong to the class of diffuse interface models, and they allow an easy modelling of transfers between phases. The considered class of models includes a hierarchy of sub-models, which take into account different levels of interactions between phases. To pursue our studies, first we have compared the so-called four-equation and six-equation two-phase flow models, including the effects of mass transfer processes. We have then chosen to focus on the four-equation model. One of the main objective of our work has been to extend residual distribution schemes to this model. In the context of numerical solution methods, it is common to use the conservative form of the balance law. In fact, the solution of the equations under a non-conservative form may lead to a wrong solution to the problem. Nonetheless, solving the equations in non-conservative form may be more interesting from an industrial point of view. To this aim, we employ a recent approach, which allows us to ensure conservation while solving a non-conservative system, at the condition of knowing its conservative form. We then validate our method and apply it to problems with complex geometry. Finally, the last part of our work is dedicated to the evaluation of the validity of the considered diffuse interface model for applications to real industrial problems. By using uncertainty quantification methods, the objective is to get parameters that make our simulations the most plausible, and to target the possible extensions that can make our simulations more realistic
Zhang, Zhong Yi. „Visualisation and quantification of the defects in glass-fibre reinforced polymer composite materials using electronic speckle pattern interferometry“. Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/22078.
Der volle Inhalt der QuelleLesponne, Martine. „Quantification de deux substances odorantes par trois sujets humains et par trois chromatographes en phase gazeuse. Contribution à la mise en évidence des points critiques de la mesure sensorielle“. Dijon, 1994. http://www.theses.fr/1994DIJOS032.
Der volle Inhalt der QuelleGhandour, Houda. „Analyse et quantification des émissions polluantes de composés organiques volatils d'origine industrielle par mesures directes aux sources“. Lille 1, 1997. http://www.theses.fr/1997LIL10057.
Der volle Inhalt der QuelleSémard, Gaëlle. „Recherche et quantification de substances cibles et émergentes dans les eaux résiduaires à l’aide de la chromatographie en phase gazeuse bidimensionnelle“. Rouen, 2009. http://www.theses.fr/2009ROUES002.
Der volle Inhalt der QuelleThe discovery of new contaminants in natural waters, with biological effects at low concentration levels, has led legislators to set emission threshold, or environmental quality standards (EQS) for a growing number of contaminants. The analysis, identification and quantification of these substances in complex matrices represent a real challenge. Comprehensive two-dimensional gas chromatography (GCxGC) is a promising separation technique that can resolve the problems of saturation of other conventional analytical techniques. Because of its important capacity of separation, steps of sample preparation have been significantly reduced compared to a conventional GC analysis, thus minimizing the loss of traces of target compounds. After optimisation of analytical conditions, the GCxGC has been applied in our study, to seek a fifty target substances and emerging compunds in raw and treated urban wastewaters from six wastewaters treatment purfication station
Monmarson, Bastien. „Simulation en présence d'incertitude d'un gazosiphon de grande échelle. Application à l'optimisation d'un nouveau système géothermique urbain“. Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAI045/document.
Der volle Inhalt der QuelleThis PhD thesis is part of the ANR project « Uncertain Flow Optimization » (UFO). The project is devoted to the development and application of efficient uncertainty quantification methods for flow analysis and optimization. In this framework, these methods are applied to the study of a large-scale airlift pump. The airlift pump is selected to be part of an innovative geothermal system, which can be exploited within an urban environment. We wish to quantify and optimize the energy potential of this new system with numerical tools. They provide both good accuracy and efficiency properties. The airlift two-phase flow simulation is based on a quasi one-dimensional drift flux model, which is implicitly solved. The solver is validated by comparison with relevant experimental airlift studies from the literature. However, these studies remain below the kilometric-targeted pipe length. Thanks to the analysis of two uncertainty quantification methods, a non-intrusive approach relying on polynomial chaos expansion and a new semi-intrusive method developed ahead of the UFO project, we perform airlift pump simulations taking into account physical and modelling uncertainties. This numerical tool is inserted into a simplified model of the complete urban geothermal system that involves surface devices, such as an air compressor. Finally, a robust preliminary optimization process is performed for two versions of the proposed geothermal urban system. They are designed respectively for heat recovery and electricity production
Luchetta, Laurent. „Caractérisation et quantification dans la basse atmosphère de composés organiques volatils biogéniques et anthropiques contribuant à la pollution de l'air“. Toulouse, INPT, 1999. http://www.theses.fr/1999INPT015H.
Der volle Inhalt der QuelleGalbincea, Nicholas D. „Critical Analysis of Dimensionality Reduction Techniques and Statistical Microstructural Descriptors for Mesoscale Variability Quantification“. The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500642043518197.
Der volle Inhalt der QuelleWiest, Laure. „Méthodologies analytiques basées sur la chromatographie liquide couplée à la spectrométrie de masse pour la quantification multi-familles de tensioactifs dans les rivières“. Electronic Thesis or Diss., Lyon, 2021. http://www.theses.fr/2021LYSE1138.
Der volle Inhalt der QuelleThe number of chemicals on the market is increasing every year. Moreover, they are more and more complex and the formulations contain mixtures that are finally disseminated in various compartments of the environment. Among these micropollutants, surfactants present some particularities. First, surfactants are complex mixtures of homologues and isomers whose composition depends on the raw materials and the synthesis processes used. Secondly, some, such as linear alkylbenzene sulfonates (LAS) and triethanolamine esterquats (TEAQ), are used in very large quantities, which may induce "pseudo-persistence" in the receiving environments. Finally, the fields of application of surfactants are extremely varied, ranging from domestic to industrial, agricultural and hospital, which suggests a large number of sources of transfer to the environment. The data concerning their occurrence are very heterogeneous according to the families, and some types of surfactants have never been looked for in rivers until now. The objective of this thesis was therefore to develop sensitive and reliable analytical methodologies to fill this knowledge gap concerning the occurrence of surfactants in the environment. In order to obtain sufficient sensitivity, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was first optimized. Contamination of instrumental blanks, in particular by anionic surfactants, at concentrations between 0.1 µg/L and 3 µg/L was observed. As the limits of quantification (LOQ) were still too high compared to the PNEC, a pre-concentration step by solid phase extraction was developed for the analysis in river water. For sediment analysis, an ultrasound-assisted extraction was optimized and validated. With LOQs between 0.015 and 0.485 µg/L for water and between 6.4 and 158 µg/kg for sediment, the analytical performances obtained are compatible with trace analysis. The application of these methodologies to river waters and sediments sampled in France showed a high occurrence of surfactants in these media. In particular, LAS have both high quantification frequencies and high mean concentration to PNEC ratios, and therefore represent a significant risk to ecosystems
Ismailov, Taner. „Quantification of resin acids, fatty acids and sterols in process and waste water from forest industry“. Thesis, Karlstads universitet, Avdelningen för kemi och biomedicinsk vetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-28179.
Der volle Inhalt der QuelleSonnabend, Kristina [Verfasser], David [Akademischer Betreuer] Maintz, Marc [Gutachter] Tittgemeyer und Mathias [Gutachter] Hoehn. „Quantification of cerebrospinal fluid dynamics using phase-contrast magnetic resonance imaging / Kristina Sonnabend ; Gutachter: Marc Tittgemeyer, Mathias Hoehn ; Akademischer Betreuer: David Maintz“. Köln : Deutsche Zentralbibliothek für Medizin, 2021. http://d-nb.info/1226872476/34.
Der volle Inhalt der QuelleGOURDON, PIERRE. „Etude physiologique d'une souche de corynebacterium glutamicum productrice d'acide glutamique : quantification des flux metaboliques et des contraintes biochimiques en phase de production“. Toulouse, INSA, 1999. http://www.theses.fr/1999ISAT0043.
Der volle Inhalt der QuelleGandubert, Anne. „Caractérisation et quantification de la phase sulfure des catalyseurs d'hydrotraitement : influence de la nature des précurseurs oxydes et des conditions de sulfuration“. Lille 1, 2006. http://www.theses.fr/2006LIL10140.
Der volle Inhalt der QuelleKhoury, Spiro. „Aspects théoriques et pratiques de la quantification des classes lipidiques par usage des détecteurs universels et de la spectrométrie de masse“. Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS191.
Der volle Inhalt der QuelleThe lipidome means the lipid subfraction of a metabolome, of a cell, a tissue or an organism. Lipidomics represents a particular field of investigation because of the functional and metabolic specificities of lipids as well as their physico-chemical properties. Lipidomics analysis represents a major change of scale with respect to lipid analysis as practiced conventionally. The aim of this work is to reach across the lipid molecular species in terms of identification and quantification in order to describe all the perturbations of a metabolic network related to a physiological or pathological state. The identification of the classes and the specie is based mainly on the use of liquid chromatography coupled to mass spectrometry. Quantification may use mass spectrometry when the specificity and low detection limits are required or the use of "universal" detectors that are nebulized detectors:evaporative detector light scattering (ELSD) or charged aerosol detector (CAD-Corona®) when the aim is to quantify the total lipid classes
Leleu, Thomas. „Variabilité spatio-temporelle de la composition des fluides hydrothermaux (observatoire fond de mer EMSO-Açores, Lucky Strike) : traçage de la circulation hydrothermale et quantification des flux chimiques associés“. Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30023/document.
Der volle Inhalt der QuelleThis thesis present a detailed study of the composition of high temperature fluid from the Lucky Strike hydrothermal field (37°N, Mid Ocean Ridge) collected during three sampling campaigns within the framework of the deep sea observatory EMSO-Azores. The hydrothermal field has developped around a fossil lava lake framed by three ancient volcanic cones. In 2013, the discovery of a new active site to the East of the system, and presenting an unprecedented fluid composition at Lucky Strike (low Cl concentration and high Fe and Mn concentration), lead to a new model of hydrothermal circulation based on chemical geothermobarometer (Si; Si-Cl) and geothermometer (Fe-Mn) applied to 13 venting sites. We defined 5 groups of sites based on their chlorinity and location around the lava lake. It appears that vapor-dominated Capelinhos fluids were extracted relatively fast from the phase separation zone (estimated at ~2600mbsf). Nevertheless, fluids in the vicinity of the lava lake, both vapor and brine dominated, display P and T conditions of equilibration lower than for Capelinhos fluids. This highlights on-going equilibration process through conductive cooling and/or brine entrainment in the upflow zone up to the layer 2A of the oceanic crust. Chlorinity variations highlight the varying residence time in the upflow of the fluids between vents which depends on physical characteristics of the crust. We studied the temporal variability of fluid composition collected between 2009 and 2015. Two time scales have been evidenced. The first is the sampling scale, i.e. ~1h, and corresponds to subsurface processes indicating that a hydrothermal fluid, conductively cooled (T<150°C), was stored in the porous substratum close to the discharge. The second is at the scale of the year. It shows fluctuations of P and T conditions in the phase separation and different degree of alteration of the substratum in the reaction zone. Intersites variations of Ca/Na ratios (proxies for albitisation) are related to phase separation expected the South Eastern sites that display a more altered substratum. To avoid this issue, we use Li and Sr isotopes which are not affected phase separation. Li concentration and isotopic composition indicates that basalt substratum is relatively fresh with W/R ratio close to 1 calculated for all groups with d7Li of fluid equivalent to substratum. Sr concentration and isotopic composition suggest higher W/R ratio (~7-8) because of seawater Sr partially removed in the recharge. Moreover, other parameters are at play such as secondary mineral formation (albite, anhydrite) during water rock interaction in the greenschist facies. Because the basalt is relatively fresh, the low metal content in the fluid around the lava lake is due to storage, in the subsurface, of approximately ~60-70% of Fe that is mobilized in the reaction zone compared to Fe-Mn rich Capelinhos fluids. Furthermore, the Cl variability from the fluids at Lucky Strike brings a unique opportunity to study the REE distribution from the reaction zone to the discharge into the deep ocean. We show that the LREE are preferentially concentrated into the brine phase. Furthermore, the Eu is linked to the Sr geochemical cycle. Dissolved REE from buoyant plume fluids highlight a scavenging effect. The Nd isotopic compositions indicate redissolution process. This Nd isotopes modification of the deep seawater is similar to the process of "boundary exchange" that occurs at the ocean/continents interface. Considering the global distribution of submarine hydrothermalism, the Nd modification at the ridge could have an impact on the global Nd cycle in the oceans and act as a "ridge exchange"
Rougemont, Blandine. „Quantification de protéines dans des matrices complexes par spectrométrie de masse : nouveaux outils et apllications“. Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1084/document.
Der volle Inhalt der QuelleTandem mass spectrometry is now a technique of choice for human or micro-organisms proteome analysis. Typically, proteins are first digested into surrogates’ peptides, separated by liquid chromatography before being analyzed by MS/MS. The ultimate goal is the identification and the quantification of these peptides, belonging to proteins and highlighting a phenotype or a cellular mechanism in a complex organism. Both targeted and untargeted approaches are used and are complementary in proteomic analysis. The work presented here is focused on the development of targeted methods, and more particularly in the SRM mode, through two applications involving micro-organisms. So, the first study concerned to absolute quantification of viral proteins of the chimeric yellow-dengue fever, vaccine candidate against dengue. By using the AQUA quantification strategy, we were able to develop, to validate and to transfer the method for the four chimeric virus serotypes. Then, problems met during development process, lead us to suggest check points to verify when using AQUA strategy. In a second part, we attempted to develop a quantitative label free analysis of 445 proteins to study the infection of the phytopathogen Dickeya dadantii, on a model plant. To ensure a simple and fast transfer of this multiplex, we purpose a new acquisition tool, independent from retention time. This tool was developed in a partnership with the R&D Sciex, Toronto and is called “Scout-SRM”
Fedi, Baptiste. „Etude multi-échelle des mécanismes d'élaboration de revêtements d'alliage zinc-nickel à base d'électrolytes alcalins : germination, complexation et structures cristallines“. Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2078.
Der volle Inhalt der QuelleThe present work aims to deepen the understanding of the mechanisms of zinc-nickelelectrodeposition in alkaline baths. Zinc-nickel deposits containing between 12% and 16%nickel known for their anti-corrosion performance. Complexing agents are required toobtain soluble and reactive nickel forms, and to stabilize the electrolytes. A study ofthe complexing mechanisms has improved the understanding of their respective role andbehavior, and their influence on the stability and the morphology and crystalline structureof the coatings obtained. The crystalline phases of electroplated zinc-nickel alloys in therange from 1% to 20% nickel content were quantified by deconvolution of potentiodynamicoxidation curves and XRD. This approach has led to a precise mapping of the alloyphases obtained as a function of the nickel content. The thermal stability of the differentphases has also been evaluated and quantified by this method. The formulation of theelectrolytes and the process parameters may modify the kinetics of coating germination. Afundamental study of the mechanisms of germination by chronoamperometry coupled witha parametric identification allows the quantification of parameter evolution in relation tonucleation phenomenon of simple elements. The study of alloy germination has shownthat decomplexing reactions are able to modify nucleation kinetics, without achieving acomplete comprehensive modeling
Qoku, Elsa [Verfasser], Thomas [Gutachter] Bier, Thomas [Akademischer Betreuer] Bier und Herbert [Gutachter] Pöllmann. „Characterization and quantification of crystalline and amorphous phase assemblage in ternary binders during hydration / Elsa Qoku ; Gutachter: Thomas Bier, Herbert Pöllmann ; Betreuer: Thomas Bier“. Freiberg : Technische Universität Bergakademie Freiberg, 2019. http://d-nb.info/1220636495/34.
Der volle Inhalt der QuelleJeudy, Jérémy. „Quantification de biomarqueurs protéiques dans des matrices biologiques complexes par spectrométrie de masse : développements et applications“. Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10242/document.
Der volle Inhalt der QuelleOver the past decade, interest in the use of biomarkers in clinical studies has greatly increased. Quantification of a candidate protein biomarker in complex samples (eg. plasma) requires targeted and multiplexed assays. Immunoassays are the gold standard for their quantification. However, with the need for targeted and multiplexed methods, recent developments in mass spectrometry (MS) make a viable alternative to ELISA. The present work has addressed the problems encountered in this type of proteomic studies, and solutions that can be explored to improve the workflow of candidate biomarker’s evaluation. Methionine peptides are generally avoided due to their susceptibility to oxidation. However, it seemed interesting to study how their endogenous modifications could affect biological processes. In a first time, apolipoproteins were dismissed as a potential biomarker of Alzheimer’s disease due to oxidation impact. In the same time, problems associated with biological sample collection and storage were highlighted. DBS (Dried Blood Spot) and Vivid device evaluation from a panel of 32 blood proteins has provided a first possible solution to overcome these troubles. Thereafter, a new peptide quantification method called MRM3 was used to overcome biological matrix complexity. Reliable level determinations of 2 plasma proteins (C-Reactive protein and TIMP-1) and 2 urinary proteins (aquaporin-2 and podocin) were obtained. To improve sensitivity and reduce analysis solvent costs, performances of a micro chromatography platform were compared to a narrow-bore platform. This study highlighted the significant impact of the matrix effect on the analytical process, requiring new strategie development. Finally, to reduce sample complexity, evaluation of wide pore solid-phase extraction cartridges has been achieved. A protocol was successfully developed to analyze enzymes contained in commercial laundry samples. Finally to optimize biological sample preparation time, heated-assisted digestion and online desalting step were successfully associated. Only few hours were then required for quantitative analysis
Simonnet, Titouan. „Apprentissage et réseaux de neurones en tomographie par diffraction de rayons X. Application à l'identification minéralogique“. Electronic Thesis or Diss., Orléans, 2024. http://www.theses.fr/2024ORLE1033.
Der volle Inhalt der QuelleUnderstanding the chemical and mechanical behavior of compacted materials (e.g. soil, subsoil, engineered materials) requires a quantitative description of the material's structure, and in particular the nature of the various mineralogical phases and their spatial relationships. Natural materials, however, are composed of numerous small-sized minerals, frequently mixed on a small scale. Recent advances in synchrotron-based X-ray diffraction tomography (to be distinguished from phase contrast tomography) now make it possible to obtain tomographic volumes with nanometer-sized voxels, with a XRD pattern for each of these voxels (where phase contrast only gives a gray level). On the other hand, the sheer volume of data (typically on the order of 100~000 XRD patterns per sample slice), combined with the large number of phases present, makes quantitative processing virtually impossible without appropriate numerical codes. This thesis aims to fill this gap, using neural network approaches to identify and quantify minerals in a material. Training such models requires the construction of large-scale learning bases, which cannot be made up of experimental data alone.Algorithms capable of synthesizing XRD patterns to generate these bases have therefore been developed.The originality of this work also concerned the inference of proportions using neural networks. To meet this new and complex task, adapted loss functions were designed.The potential of neural networks was tested on data of increasing complexity: (i) from XRD patterns calculated from crystallographic information, (ii) using experimental powder XRD patterns measured in the laboratory, (iii) on data obtained by X-ray tomography. Different neural network architectures were also tested. While a convolutional neural network seemed to provide interesting results, the particular structure of the diffraction signal (which is not translation invariant) led to the use of models such as Transformers. The approach adopted in this thesis has demonstrated its ability to quantify mineral phases in a solid. For more complex data, such as tomography, improvements have been proposed
Poupon, Julien. „Quantification des voies métaboliques de l'éthanol par le cytochrome P450 2E1 : rôles respectifs de l'acétaldéhyde et des radicaux libres hydroxyéthyles dans l'hépatotoxicité de l'éthanol“. Brest, 2003. http://www.theses.fr/2003BRES3108.
Der volle Inhalt der QuelleHepatotoxicity of alcoholic intoxication brings into play the products resulting from the metabolism of ethanol by the cytochrome P4502E1 (CYP2E1): acetaldehyde (two-electron oxidation), and hydroxyethyl radicals (HER) (one electron-oxidation). This products can form adducts with surrounding molecules. CYP2E1 is the principal site of oxidation microsomal of ethanol (84% in the rat, only 30% in the Man ). Ethanol oxidation leads to the formation of acetaldehyde and HER in the 9/1 ratio. The contribution of the mono-electronics pathway, revealed by spin-trapping method of HER, accounts for 5 to 7 %. Incubation of guanine with HER formed in situ results in HER-guanine adducts (HEG) (12% of incubated guanine). However, HEG adducts could not be detected either in DNA from several biological materiels. Alkylation of the microsomals proteins shows that adduits HER are formed mainly with the CYP2E1. The formation of HER-CYP2E1 does not affect the catalytic activity under normal conditions
Kouzayha, Abir. „Développement des méthodes analytiques pour la détection et la quantification de traces des HAP et de pesticides dans l'eau : application à l'étude de la qualité des eaux libanaises“. Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14414/document.
Der volle Inhalt der QuelleWater pollution presents a very critical problem facing industrial and developping countries. The environmental monitoring of the contaminants seems necessary to understand their sources and impacts. Among a wide variety of organic pollutants present in water,polycyclic aromatic hydrocarbons (PAHs) and pesticides are of particular importance as widespread, persistent, and toxic contaminants. They are usually present at trace levels in theacquatic surfaces; therefore their detection and control require selective and sensitiveanalytical procedures. The Solid-Phase Extraction (SPE) followed by the Gas-Chromatography coupled to Mass Spectrometry (GC-MS) are the most commonly usedtechniques for their analysis in water. Thesis objectives are focused on the development of new analytical methods for the extraction and analysis of these two families of pollutants present in water. To overcone the contraints of the traditional SPE, a new approach was developed consisting on the introduction of the centrifugation in several steps of the procedure. The new method showed practical environmental and economical advantages interms of sample preparation time, simplicity, reduction in solvent use, and cost and isparticularly suitable for routine applications requiring a high sample throughput. Aprogrammed temeperature vaporizing (PTV) injection method was also optimized and validated in order to improve the detection limits for the GC-MS analysis of PAHs. The evaluation of the quality of different water systems in Lebanon including rainwater,groundwater, drinking water and surface water was accomplished in this study
Le, Ven Jessica. „Contribution à l'étude du lien entre Annonaceae et parkinsonisme : identification et quantification d'acétogénines par déréplication; métabolisation de phase I et approche de la distribution de l'annonacine“. Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00784165.
Der volle Inhalt der QuelleZhang, Gongwang. „THE FORMATION MECHANISM OF α-PHASE DISPERSOIDS AND QUANTIFICATION OF FATIGUE CRACK INITIATION BY EXPERIMENTS AND THEORETICAL MODELING IN MODIFIED AA6061 (AL-MG-SI-CU) ALLOYS“. UKnowledge, 2018. https://uknowledge.uky.edu/cme_etds/90.
Der volle Inhalt der QuelleComte, Julien. „Mise au point d’une méthodologie d’échantillonnage utilisant la micro-extraction sur phase solide pour la quantification de goudrons sur des procédés de thermolyse de la biomasse“. Grenoble 1, 2008. http://www.theses.fr/2008GRE10152.
Der volle Inhalt der QuelleThe gasification of biomass by thermochemical processes is presently a promising method of producting H2 and CO which are used for synthesis of biogasoil. However, the thermal treatment of biomass leads to the production of unwanted compounds referred to as "tar" (heavy hydrocarbons) of which the content in syngas must to be inferior to 0. 1 mg. Nm-3. Knowledge oftar content is consequently needed. To this end, a sampling methodology using SPME (Solid Phase MicroExtraction) was developed for the quantification of "model compounds" which represents the total tar content mainly emitted by two gasification or pyrolysis processes. Introduction of the notion of model compounds is intended to simplify the sampling methodology on one hand to overcome the possible limitations related to the sampling system developed in this work to allow SPME extraction on the other. For the two thermochemical processes,15 model compounds were selected. The quantification of these compounds required calibration of SPME fibres (polydimethylsiloxane coating) which allow us, over a range oftemperatures, to establish the absorption profiles and to determine distribution coefficients. Influence of the sampling conditions on the absorption and performance of the coupled SPME-gas Chromatography were also evaluated. Ln order to avoid repetitive calibrations, a model based on thermodynamic considerations was developed to speed-up determination of the distribution coefficient
Oursel, Delphine. „Influence de l’expression de l’ATP synthétase sur la composition lipidique des membranes bactériennes chez Escherichia coli : Identification et quantification relative des phospholipides et acides gras constitutifs par spectrométrie de masse“. Rouen, 2008. http://www.theses.fr/2008ROUES062.
Der volle Inhalt der QuelleFor years, investigations of growing interest deal with the potential lipids preference of membrane proteins and/or enzymes, these affinity phenomenons are supposed to induce the formation of lipids domains also called lipids rafts inside biological membranes. This thesis focused on the ability of ATP-synthetase, a membrane protein, to induce lipids domains in a cellular model, the E. Coli bacteria. Hence, 4 bacterial strains were studied to evaluate the influence of protein expression, a wild type and three genetically modified strains with variable enzyme rates. Analytical methodologies were developed for this purpose and involved various MS techniques. Then, LC-MS and GC-MS techniques were used for the analysis of phospholipids and constitutive fatty acids, respectively. This approach provided the identification of all the phospholipids. Moreover, the structure of the constitutive fatty acids and their location on the glycerol backbone were determined
Huynh, Huu Hien. „Développement d’une méthode de référence candidate pour la quantification de la procalcitonine dans le sérum humain“. Thesis, Université Paris sciences et lettres, 2021. http://www.theses.fr/2021UPSLS037.
Der volle Inhalt der QuelleProcalcitonin measurement is a usefully tool to aid the early diagnosis and antibiotic stewardship for patients with sepsis. As sepsis diagnosis and antibiotic stewardship rely on fixed clinical cutoffs (threshold concentration values), ensuring accuracy and comparability of PCT results over time and space is essential to ensure an appropriate diagnostic and therapeutic management. Multiple immunoassays have been developed and commercialized. However, comparability of results remains questionable. There is no metrological traceability to the international system of units (SI) for PCT measurement due to the lack of higher order reference method and certified reference materials.This work initially consisted in documenting the current state for results’ comparability between the different commercially available immunoassays for PCT in order to evaluate the need to establish metrological traceability to the SI. The evaluation of correlation studies and external quality assessment schemes results indicate that properly evaluating the current state of result’s comparability and discriminating the origin of result’s discrepancies is made difficult because studies were conducted in non-harmonized conditions and commutability of the materials was not characterized. Thus, it seems essential to conduct quality external evaluation using commutable control materials. In order to evaluate accuracy of commercially available immunoassays for PCT and to meet the regulatory requirements for the metrological traceability of results, a candidate reference method based on isotopic dilution liquid chromatography coupled to mass spectrometry was developed and validated for an absolute quantification of PCT in human serum with a limit of quantification of 0.25 ng/mL. Results traceability to the SI units could be established thanks to a thorough purity assessment of the primary calibrators by amino acid analysis and correction of impurities contribution
Santos, Ivan. „Quantification of gas-phase ion-molecule reactions of complex organic compounds and a study of the factors involved in these determinations by Fourier transform ion cyclotron resonance mass spectrometry /“. The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487335992902583.
Der volle Inhalt der QuelleGru, Yvan. „Couplage avancé de type HPLC avec préconcentration en ligne et spectrométrie de masse (SPE-LC/MS/MS) : identification et quantification de micropolluants organiques dans les eaux : effets de la matrice“. Rennes 1, 2010. http://www.theses.fr/2010REN1S020.
Der volle Inhalt der QuelleTo analyze swiftly and reliably numerous pesticides in waters, an on-line solid phase extraction liquid chromatography technique (on-line SPE-HPLC) coupled with triple quadripole linear ion trap mass spectrometry (Q-Trap MS/MS) procedure was developed for a large range of chemical families with detection limits at the 10 ng/L level. In this study, triazines, phenylureas, organophosphorus compounds and others (near than 210 compounds) were tested in the same ESI positive chromatographic run (less than 25 min). 2 ml of water sample (filtered if necessary) were injected into the SPE-HPLC system through a preconcentration cartridge. Analytes were eluted by a suitable mobile phase towards an analytical column (monolithic stationary phase), then detected and quantified by the mass spectrometer (MS/MS). The LOQ were achieved under the 10 ng/L level for the most of compounds in the both matrices (tap water and river water). Degradation of molecules was studied by research of few metabolites, and also by modification of storage conditions, showing the importance to evaluate stability of compounds in aqueous environment (hydrolysis, photolysis). The study was then focused on the identification by using the MRM-EPI scan mode (Full scan MS/MS), available on this kind of mass spectrometer. Results show that on-line-SPE-LC technique, coupled with hybrid triple quadripole linear ion trap mass spectrometry is a suitable way to determine multiple organic residues in waters. Finally, matrix effects theme was largely approached, since developed technique gave place non negligible signal suppressions for few compounds (signal enhancement more rarely). Matrix effects origin was evaluated by post-column introductions tests, showing that Electrospray ionization is a critical point. It was necessary to bring solutions of the control and the reduction of these annoying effects in the just restoration of an analyte concentration. The internal calibration showed effective and so was chosen, by application or not of an internal standard adapted for a particular molecule