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ANJOS, ANDREA CRISTINA CARVALHO DOS. "ANALYSIS OF AN IN SITU TABULATION STRATEGY OF COMBUSTION CHEMICAL KINETICS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=19456@1.
Pełny tekst źródłaA simulação numérica de processos de combustão é uma ferramenta cada vez mais utilizada para o projeto, a análise e a otimização de turbinas, motores e fornos de combustão, entre outros. No entanto, um dos principais inconvenientes que limitam a descrição fiel da realidade de modelos de combustão é o esforço computacional necessário para a solução das equações de transporte das propriedades do escoamento reativo, como frações de massa das espécies químicas, que incluem um termo fonte não linear associado à lei de Arrhenius. A rigidez e a carga computacional relacionadas com a determinação deste termo domina o custo de simulações que empregam modelos detalhados da cinética química da combustão. Esta dissertação descreve um estudo cujo objetivo é reduzir tais custos mediante a utilização de uma técnica de tabulação automática da evolução termoquímica da mistura. Assim, este trabalho apresenta a discussão do estado da arte da técnica denominada tabulação adaptativa in situ, que exibe desempenho considerável em termos de tempo computacional, na determinação dos termos fontes químicos, e propõe uma modificação do algoritmo atrasando o início da tabulação, para evitar o armazenamento de composições existentes apenas no estado transiente da queima, as quais não são representativas do regime estatisticamente estacionário. Um estudo dos resultados obtidos, em um reator parcialmente agitado com CO/O2, mostra ganhos superiores a 95 por cento na altura da árvore binária utilizada para tabulação, isso se reflete no custo de armazenamento e na acurácia dos resultados. Uma análise do tempo computacional caracteriza situações em que a nova estratégia de tabulação pode levar à redução do mesmo, quando comparado com a estratégia original. Seu desempenho é confirmado pelo estudo do sistema químico CH4/ar.
The numerical simulation of combustion processes is an important tool used for design, analysis and optimization of turbines, combustion engines and furnaces, among others. However, one of the major drawbacks that limit the faithful description of reality of combustion models is the computational effort required for the transport equations solution of reactive flow properties such as chemical species mass fractions, which include a nonlinear source term associated to the Arrhenius law. The stiffness and the computational burden related to the determination of such term, largely dominate the cost of simulations that employ detailed models of chemical kinetics combustion. This dissertation describes a study whose objective is to reduce these costs by using a of automatic tabulation technique of the mixture’s thermochemical evolution. Hence, this work presents a state of the art discussion of the technique named in situ adaptive tabulation – ISAT, which shows considerable performance in terms of computational time for the determination of the chemical sources terms, and proposes a modification in the algorithm by delaying the table start to avoid the storage of compositions that exist only in transient state, and which are not statistically representative of the stationary regime. A systematic study of the results in a partially stirred reactor with CO/O2, shows more than 95 per cent gains at the binary tree height used for tabulation, the gains are also optimistic in the storage demand and the results accuracy. A computational time analysis characterizes situations in which the new strategy tabulation could reduce it, when compared to the original algorithm. The strategy performance is confirmed by the study of the chemical system CH4/ar.
Badmaarag, Ulzii-Orshikh. "Optical Chemical Sensing Device for In-situ Non-Invasive Gas Monitoring". University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1583155117533193.
Pełny tekst źródłaBaraga, Joseph J. (Joseph John). "In situ chemical analysis of biological tissue--vibrational Raman spectroscopy of human atheroschlerosis". Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/12875.
Pełny tekst źródłaIncludes bibliographical references (leaves 209-223).
by Joseph John Baraga.
Ph.D.
Maillet, Anaïs. "Interactions argilite de Tournemire / fer métal en contexte in situ : résultats à 10 ans de contact". Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT2309/document.
Pełny tekst źródłaWithin the framework of a long lived radioactive waste storage concept in deep geological layer developed by Andra, IRSN leads an in situ study on the Experimental Station of Tournemire, in association with EDF to determine the interactions steel/argillite in a natural context. After 10 years of interaction, two drillings overcoring performed to characterize the processings of the Tournemire argillite in contact with carbon and stainless steels and to compare reactive phenomena highlighted and those induced by simulations tools combining chemistry and transport.Argillite/carbon steel samples show a significant corrosion of steel disk. Iron released, in the form of rings and cracks in the rock, disrupts the argillite in contact resulting in mineralogical and structural changes. Iron oxides precipitation and a calcite and smectitic leaf of mixed-layers I/S dissolution are identified. A succession of areas: metal/metal corroded/argillite disturbed/argillite is highlighted and porosity variations are observed on the interfaces between two areas. Geochemical simulations show that major changes are initiated speedly during establishment of the system and the oxygen trapped in the closed system is consumed by the corrosion of steel but mostly it diffuses into the surrounding material through concentration gradient.Argillite/stainless steel samples have a very low pitting corrosion of steel disk. This does not seem to affect the mineralogy of the argillite in contact
Quig, Lauren Dekker. "Transport of Heat Activated Persulfate and Its Application for In-situ Chemical Oxidation of Residual Trichloroethylene". PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2629.
Pełny tekst źródłaRead, Betsy A. "Structural analyses and site-directed mutagenesis of the 33 KDA manganese-stabilizing protein from anacystis nidulans R2". Virtual Press, 1989. http://liblink.bsu.edu/uhtbin/catkey/560292.
Pełny tekst źródłaDepartment of Biology
SRIVASTAVA, PRIYANK. "ANALYSIS OF IN-SITU BIORESTORATION OF CONTAMINATED SEDIMENT USING HOLLOW FIBER MEMBRANES". University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1132113070.
Pełny tekst źródłaPoon, Kelvin Weng Chun. "In situ chemical analysis of tattooing inks and pigments : modern organic and traditional pigments in ancient mummified remains". University of Western Australia. Centre for Forensic Science, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0257.
Pełny tekst źródłaNeuhuber, Stephanie Maria Ulrike. "In situ measurements of redox chemical species with amperometric techniques to investigate the dynamics of biogeochemical processes in aquatic systems". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/25737.
Pełny tekst źródłaAbécassis, Benjamin. "Suivi in situ de la nucléation-croissance de nanoparticules d'or". Phd thesis, Ecole Polytechnique X, 2006. http://tel.archives-ouvertes.fr/tel-00285508.
Pełny tekst źródłaAnrès, Philippe. "Développement de nouvelles méthodologies de préconcentration électrocinétique in-situ en électrophorèse capillaire pour l'analyse de traces". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://pastel.archives-ouvertes.fr/pastel-00744659.
Pełny tekst źródłaMambingo, Doumbe Samuel. "Simulation de la phase gazeuse des réactions tribochimiques des additifs phosphorés et soufrés". Thesis, Ecully, Ecole centrale de Lyon, 2012. http://www.theses.fr/2012ECDL0063.
Pełny tekst źródłaMastering the addivation is one of the biggest issues for the lubricants formulation, especially in the automobile industry. However automotive lubricants are very complex systems due to the numerous additives mixed with base oils. Many interactions can occur between additives, especially between surface additives. Organic phosphites and organic polysulphides have already demonstrated their effectiveness as surface additives. However, despite their widespread use in the formulations of automotive lubricants, few studies deal with the interactions taking place between these two types of compounds. The aim of this study is to understand the interactions, antagonistic or synergetic effect between these kinds of additives using Gas Phase Lubrication (GPL) approach. A Environmental Controlled Tribometer (TEC) was used as a tool to simulate the interaction between organophosphate additives and polysulfurous additives. In situ surface analysis was performed in the tribofilm formed during friction using of X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy(AES) in order to avoid any oxidation or air contamination. The molecules selected for the study can be same as the additive like the TPS molecules which are widely used as lubricant additives. Howeverto simulate the phosphite chemical function of phosphite additives, we need to select smaller molecule having the same chemical function. These molecules are dimethyl phosphite (DMPi), trimethylphosphate (TMPi) for simulating the phosphite chemical function and organic polysulphides (TPS44and TPS32). The study of the tribochemical reactions of organic phopshites allowed to clearly characterise the ambivalence of DMPi, which can react like a phosphite and induce iron phosphide formation or react like a phosphate. Ab initio numerical simulation on TMPi dissociative adsorption was carried out to identify the reactions pathways leading to iron phosphide formation. The tribochemical reaction of TPS44 on metallic iron surface leads to the formation of iron disulphidebased tribofilm. The binary vapours mixtures studied by GPL allowed to clearly identify the importance of the vapour concentration ratio between phosphite and polysulphide. Liquid phase experiments were also carried out to confirm the trend observed in GPL approach
Moulay, Valentin. "Recherche de chimie prébiotique et d'indices de vie sur les mondes océans par analyse in situ de matière organique". Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASP092.
Pełny tekst źródłaThe presence of oceans beneath the surface of some of Jupiter's (e.g. Europa) and Saturn's (e.g. Titan, Enceladus) icy satellites, coupled with the existence of geysers that allow their depths to be sampled, has highlighted the strong exobiological potential of these planetary bodies in the solar system. Such discoveries have motivated the development of future space missions (Dragonfly for Titan and mission concepts for Europa and Enceladus) to understand the surface chemistry of these ocean worlds, and by extension to search for traces of prebiotic chemistry or past or present life. The search for such signatures requires a chemical analyzer on board the probes that will be sent into the outer solar system. Many analytical techniques can be used, but gas chromatography-mass spectrometry (GC-MS) appears to be one of the best techniques for answering these questions, thanks to its heritage in space exploration, its ability to analyze a wide range of organic compounds, and its potential for detecting biosignatures, especially by studying the enantiomery of chiral species.The aim of this thesis is to prepare for future in situ chemical analysis of these icy moons, both by improving our scientific knowledge and by technically optimizing our instruments. The main purpose is to evaluate and optimize the analytical capabilities of GC-MS and associated sample preparation methods, in order to detect organic molecules and biosignatures within the analytical constraints known and/or expected on these planetary bodies (richness in organic matter in samples from Titan, and presence of water and salts in samples from the surface of Europa and Enceladus, etc.). In the case of Europa and Enceladus, the study of hypersaline terrestrial samples has highlighted the ability of GC-MS and associated pretreatment methods to find organic molecules of interest for exobiology, despite the presence of salts. In order to assess the impact of salt on these methods, a desalination protocol was developed and implemented. In addition to the analytical aspect, my work has enabled the selection and characterization of the performance of the chromatographic columns (general and chiral) that will be integrated into the DraMS instrument on board the Dragonfly probe (e.g. Dragonfly Mass Spectrometer, DraMS). For these different aspects, this work was based on the study of synthetic analogous samples (tholins for Titan) as well as natural ones (hypersaline lake for Europa and Enceladus)
Scott, Paul Robert Wieliczka David Michael. "An in situ x-ray photoelectron spectroscopy analysis of thin films created through physical vapor deposition of aluminum and plasma enhanced chemical vapor deposition of trimethylsilane". Diss., UMK access, 2007.
Znajdź pełny tekst źródła"A thesis in physics." Typescript. Advisor: David M. Wieliczka. Vita. Title from "catalog record" of the print edition Description based on contents viewed May 23, 2008. Includes bibliographical references (leaves 69-70). Online version of the print edition.
Wu, Yongqi. "Multi-parameter Fluorescent Analysis of Magnetically Enriched Circulating Tumor Cells". The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1408633549.
Pełny tekst źródłaCaglar, Basar. "Nox Storage And Reduction Over Ce-zr Mixed Oxide Supported Catalysts". Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610418/index.pdf.
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-hydroxy carboxylic acid. 10% BaO (w/w) and 1% Pt (w/w) were deposited on synthesized mixed oxide and reference alumina support via incipient wetness impregnation. Prepared catalysts were characterized by BET, XRD and in-situ DRIFTS. Pt/BaO/CexZr1-xO2 catalysts (x= 0.75, 0.5, 0.25) exhibited higher surface than pure ceria and zirconia supported catalysts and highest surface was observed for Pt/BaO/Ce0.5Zr0.5O2. The reducibility of catalysts was tested by Temperature Programmed Reduction (TPR). It was observed that the reducibility of Pt/BaO/CexZr1-xO2 catalysts increases with incorporation of Zr into ceria lattice. Pt/BaO/Ce0.25Zr0.75O2 showed the highest reducibility. The Pt dispersions of catalysts were determined by CO chemisorption. The highest Pt disperison was observed in the presence of Pt/BaO/Ce0.5Zr0.5O2 catalyst. NOx storage and reduction efficiency of the catalysts were determined by transient reaction analysis in a home-built setup at 350oC. The reaction results revealed that all catalysts exhibit similar NOX storage and reduction performance. The NOX storage performances of all catalysts were differentiated via in-situ DRIFTS analysis. Pt/BaO/CexZr1-xO2 (x= 0.75, 0.5, 0.25) catalysts revealed higher performance than the ceria and zirconia supported catalysts. Pt/BaO/Ce0.5Zr0.5O2 catalyst absorbed highest amount of NO on the surface in the form of nitrate. The reduction behaviours of catalysts also were investigated by in-situ DRIFTS. It was observed that nitrates and nitrites were completely removed from the surface after reduction by H2 at 300oC.
Ali, H. R. H. "Vibrational spectroscopic techniques (Raman, FT-IR and FT-NIR spectroscopy) as a means for the solid-state structural analysis of pharmaceuticals". Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/3343.
Pełny tekst źródłaBrevet, Aude. "Les premiers instants de la croissance de films minces d'oxydes métalliques par MOCVD : caractérisation physico-chimique de l'interface film/substrat". Phd thesis, Université de Bourgogne, 2006. http://tel.archives-ouvertes.fr/tel-00011989.
Pełny tekst źródłaLa formation d'une couche interfaciale de SiOy<2, par interaction du précurseur Ti(OCH(CH3)2)4 avec le substrat, précède la formation de TiO2 et conduit à la présence de carbone à l'interface. La diffusion de silicium au sein de la couche superficielle de TiO2 a été constatée à la température de dépôt de 675 °C. Dès les premiers instants de la croissance, des cristallites de structure anatase et rutile se forment au sein de la couche de TiO2 amorphe. La croissance des grains de rutile s'arrête en cours de dépôt. Celle des grains d'anatase se poursuit sous forme de colonnes monocristallines.
Panicaud, Benoît. "Contraintes « de croissance » et cinétiques d'oxydation dans des couches d'oxydes thermiques de Fer et de Nickel ;Etude in-situ par Diffraction des Rayons X et modélisation". Phd thesis, Université de La Rochelle, 2004. http://tel.archives-ouvertes.fr/tel-00169180.
Pełny tekst źródłaSzopa, Cyril. "Analyse moléculaire in situ d'un noyau cométaire : Développement et évaluation des performances d'un système de chromatographie en phase gazeuse pour la mission Rosetta". Phd thesis, Université Paris XII Val de Marne, 2001. http://tel.archives-ouvertes.fr/tel-00007459.
Pełny tekst źródłaParmi les différentes méthodes employées jusqu'à aujourd'hui, l'analyse in situ est la seule capable de nous procurer des informations directes sur le noyau cométaire. C'est cette approche que nous avons choisi d'employer en contribuant à l'expérience COmetary Sampling And Composition (COSAC). Cette dernière fait partie des expériences embarquées dans la sonde Rosetta dédiée à l'analyse d'une comète et de son environnement. Compte tenu du nombre important de composés probablement présents dans le noyau cométaire et de la robustesse de cette technique analytique, la chromatographie en phase gazeuse (CPG) apparaît comme la plus appropriée pour l'identification et la quantification des composés présents dans le noyau cométaire. Nous avons donc développé un sous-système chromatographique qui fera partie intégrante de l'expérience COSAC.
La principale tâche de ce travail a été de concevoir la partie séparative de ce système, constituée de colonnes chromatographiques connectées en parallèle. Cette partie a été développée en vue de la séparation et de l'identification d'une large gamme de composés d'intérêt cométaire initialement identifiés, allant des composés les plus légers (gaz nobles) jusqu'à des espèces organiques de poids moléculaire élevé (HAP). A cette fin, un travail expérimental a été mené pour comparer les propriétés analytiques (sélectivité, efficacité) des nombreuses colonnes chromatographiques candidates, dans les conditions de température in situ (isotherme comprise entre 30°C et 60°C). Cette étude, associée à la prise en compte de contraintes opératoires (présence d'eau, faible consommation de gaz vecteur, robustesse des colonnes...), a permis d'aboutir à la sélection et à l'optimisation des caractéristiques de 5 colonnes chromatographiques différentes. Cette combinaison correspond au nombre minimal de colonnes permettant de répondre aux objectifs du système chromatographique.
Une fois les colonnes de l'expérience sélectionnées, elles ont été soumises aux différentes contraintes liées à l'instrumentation spatiale (vibrations, cycles de température) et à l'environnement spatial (pression réduite, radiations) pour tester leur robustesse. Les résultats montrent que les performances de ces colonnes ne sont affectées ni par ces tests, ni par la présence d'eau dans l'échantillon, prouvant ainsi leur capacité à être utilisées dans le système chromatographique.
Ensuite, les performances réelles de ce système ont été évaluées à l'aide d'un outil de laboratoire reproduisant l'expérience COSAC (colonnes, détecteurs) et les conditions opératoires in situ (température, pression externe). Cette étude a permis de montrer que les propriétés analytiques du système ne sont pas significativement altérées comparativement à celles observées à pression atmosphérique en sortie de colonne, et que le gain de vitesse entraîné par la présence d'une pression réduite était bénéfique par la réduction du temps d'analyse. De plus, la pression en tête de colonne optimale de l'expérience a pu être fixée (150 kPa). Nous avons également montré que l'expérience devrait permettre d'identifier environ 75% des composés initialement ciblés.
Enfin, la sensibilité du système (colonne+détecteur) a été évaluée en mesurant la quantité minimale détectable d'un composé présent dans un mélange analysé. Elle est comprise entre 10-11 mol et 10-12 mol, ce qui correspond à un rapport de volume de 1 ppm dans le cas le plus favorable où il y a suffisamment d'échantillon gazeux pour remplir complètement la boucle d'échantillonnage. Ce dernier résultat permet de conclure que le système développé permet l'analyse de composés traces présents dans le noyau cométaire et que sa sensibilité est plus importante que celle des observations spectroscopiques de la coma (environ 0,1%).
Au delà du travail expérimental de mise en œuvre de ce système chromatographique, nous avons pu également montrer que le couplage d'une des colonnes avec les techniques préparatives des échantillons de COSAC devrait permettre d'analyser des espèces chimiques qui ne pouvaient pas l'être par CPG directe (acides aminés), ou de mettre en évidence des composés réfractaires à partir de leurs produits de dégradation thermique (poly-HCN). Enfin, nous présentons les premiers travaux expérimentaux et théoriques développés en vue de l'interprétation des futures données collectées par l'instrument de vol.
Hastings, Jesse L. "Optimization and Analysis of a Slow-Release Permanganate Gel for Groundwater Remediation in Porous and Low-Permeability Media". Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1430842349.
Pełny tekst źródłaPotin, Yves. "Spectrométrie Mössbauer in situ : application a l' étude de perovskites non-stoechiométriques et de fluorures d'étain". Phd thesis, Université Sciences et Technologies - Bordeaux I, 1986. http://tel.archives-ouvertes.fr/tel-00204092.
Pełny tekst źródłaChouchi, Dalida. "Extrographie : couplage in situ entre extraction et chromatographie supercritique, application à la déterpénation et à la détoxification des huiles essentielles d'agrumes". Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL022N.
Pełny tekst źródłaBen, Hassan Ines. "Analyse multi-échelle de la filtration sur microsive de particules modèles inertes et biologiques : caractérisation in situ du dépôt par microscopie confocale". Phd thesis, INSA de Toulouse, 2014. http://tel.archives-ouvertes.fr/tel-01073549.
Pełny tekst źródłaPhilippon, David. "Lubrification par la phase gazeuse : tribochimie des additifs phosphorés et boratés". Phd thesis, Ecole Centrale de Lyon, 2007. http://tel.archives-ouvertes.fr/tel-00280892.
Pełny tekst źródłaMlwilo, Nolasco Anton. "Radiometric characterisation of vineyard soils, Western Cape, South Africa". Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6358_1318594333.
Pełny tekst źródłaMosbye, John Erlend. "Colloidal Wood Resin: Analyses and Interactions". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-298.
Pełny tekst źródłaThis thesis presents studies of the interactions between suspended particles and dissolved and colloidal substances (DCS) in process water. The main focus has been to determine if colloidal wood resin is adsorbed by suspended fines or fillers, and how the dissolved material influences this adsorption. The effect of some synthetic polymers on this adsorption has also been investigated.
Successive refining of mainly Norway spruce followed Successive refining of mainly Norway spruce followed by removal of the produced fines after each refining stage, resulted in fines with different physical and chemical properties. In the first refining stage mainly flake-like fines were produced, while more fibrillar fines were produced in later refining stages. The different types of fines were analysed for both the bulk and the surface composition. Variation in the chemical composition between the fines was particularly striking with regard to the surface composition. Special attention was also given to the amount and origin of charged groups since these may consume cationic additives in the papermaking process. After alkali treatment, between 80 and 90% of all the charged groups measured by polymer adsorption originated from three uronic acids.
Fines were shown to adsorb model colloidal wood resin, but the adsorption was greatly influenced by the pH or salt content. Also the amount of dissolved components in the suspension, which sterically stabilised the colloidal wood resin, was shown to strongly influence the adsorption of the colloidal wood resin to the fines. The flake-like fines adsorbed the colloidal wood resin to a higher extent than the fibrillar fines. This selectivity was also possible to obtain by using polyethyleneoxide (PEO). PEO removed the sterically stabilised colloidal wood resin more efficiently when flake-like fines rather than fibrillar fines were present. For comparison, cationic polyacrylamide (CPAM) did not have this selectivity. The selectivity of PEO was explained by a higher affinity to flake-like fines than fibrillar fines. It was shown that more PEO adsorbed to flake-like fines rather than to fibrillar ones. PEO may adsorb to extractive surfaces, but was inhibited by adsorbed components from the dissolved fraction. The degree of stabilisation was also shown to influence the adsorption of the colloidal wood resin by other particles like fillers. This adsorption, which was energetically favourable, did not occur at high concentrations of dissolved material.
Bondon, Arnaud. "Stabilité des écoulements stratifiés en coextrusion : Etude multi-échelle du rôle de l’architecture du copolymère aux interfaces". Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0100.
Pełny tekst źródłaSeveral polymers can be combined in one multilayer structure by reactive coextrusion. Tie-layers are often used to compatibilize the adjacent layers and may reduce or suppress the interfacial instabilities and the defects in the multilayer coextrusion flow. However, an additional defect defined as the “grainy” defect can be observed. In the best of our knowledge, no study in literature has been devoted to understand its origin. The phenomena are quite complex due to the coupling of the effects of flow and the physico-chemical mechanisms at the interface. The aim of this work is to understand the relations between the instabilities and the defects encountered in multilayer coextruded films and the role of the copolymer formed in-situ between tie and barrier layers. Polyamide 6 (PA6) and ethylene-vinyl alcohol copolymer (EVOH) were used as the barrier layers sandwiched in a polypropylene (PP) with or without a polypropylene grafted maleic anhydride (PP-g-MA) as a tie-layer. The effect of the process parameters and the structure of the polymers on the generation of the “grainy” defect was assessed in correlation with the rheological and the physicochemical properties of the layers. These experiments have shown that this defect appeared mainly in the compatibilized EVOH system and could be distinguished from the usual coextrusion instabilities. The interfacial properties between tie and barrier layers were investigated. The characterization of the interfacial morphology by TEM and AFM highlighted an irregular and rough interface between PP-g-MA and EVOH while a flat interface was observed with PA6 and PP-g-MA. Step shear and startup elongation rheology was shown to be sensitive to the copolymer at the polymer/polymer interface. The study of the interfacial properties highlighted that the copolymer architecture significantly impacts the interfacial roughness and the rheology of the multilayer stuctures. Hence, relations between the relaxation process, the interfacial morphology and the copolymer architecture were established in correlation with the generation of the macroscopic grainy defect in coextrusion
Kiflemariam, Sara. "Expression and Mutation Analyses of Candidate Cancer Genes In Situ". Doctoral thesis, Uppsala universitet, Institutionen för immunologi, genetik och patologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-184510.
Pełny tekst źródłaDarnell, Jason Ellis. "IN-SITU LEAD IMMOBILIZATION USING PHOSPHATE BASED BINDERS". MSSTATE, 2004. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07072004-145059/.
Pełny tekst źródłaMaphutha, Malebelo. "In situ sintering study of model nickel catalysts". Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13326.
Pełny tekst źródłaLipid catabolism plays a significant role in the survival of M.tb inside the host. The development of analytical techniques such as gas chromatography mass spectroscopy (GCMS) and liquid chromatography mass spectroscopy (LC-MS) has become popular as metabolomics tools in the study of such catabolic pathways. The development of biomarkers and internal standards to perform quantitative and qualitative analysis of metabolites in the catabolic pathway would be an attractive tool. Thus, cholesterol derivatives were synthesized as thia-, fluoro- and deuterium labeled analogs. Sulfur was incorporated into cholesterol at positions, C3 as well as C23. The 3â-mercaptocholest-5-ene was synthesized to block the initial stage of cholesterol catabolism and evaluate whether side chain degradation can still occur. Fluorine was integrated into the cholesterol backbone at C3 to evaluate the side-chain degradation in the absence of cholesterol oxidase activity. Steroids with fluorine at C6 are known to have good biological activity and were for this reason also synthesized. Deuterium labeled compounds were synthesized and used as internal standards for GC-MS analysis. As an alternative to cholesterol catabolism, fatty acids like stearic acid are important in producing building blocks for long chain mycolic acids which provides protection to the mycobacterium. For this reason thiastearic acid derivatives were synthesized and evaluated as biomarkers.
Haidara, Fanta. "Étude des mécanismes de formation de phases dans des films minces du système ternaire Al-Cu-Fe". Phd thesis, Université Paul Cézanne - Aix-Marseille III, 2011. http://tel.archives-ouvertes.fr/tel-00647911.
Pełny tekst źródłaClark, Peter. "Towards in-situ characterisation of formulated products". Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6973/.
Pełny tekst źródłaBastway, Mohammed Omer Abdalrahim. "Effect of Khartoum City for Water Quality : chemical analyses". Thesis, Linköping University, Department of Water and Environmental Studies, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10239.
Pełny tekst źródłaThis thesis assesses the water quality of the River Nile around the city Khartoum in Khartoum State, Sudan Republic, and investigates eventual influences of the city on the River Nile by analysis of the following parameters: temperature, pH, and conductivity, and Adsorbable Organic Halogen (AOX), cadmium (Cd), lead (Pb), chromium (Cr), Total Organic Carbon(TOC) and Nitrate (NO3− ). A survey of the area is also included. It was concluded that the city Khartoum added small but legible concentrations of cadmium, lead, chromium and TOC to the river Nile. However, the resulting concentrations were all within acceptable levels. Also, the observed results showed that the Blue and White Nile, which merge together upstream on the outskirts of Khartoum, had concentrations of AOX resp. chromium, which were not suitable for drinking water.
Roullier-Gall, Chloé. "Analyses métabolomiques du vin : "chemical messages in a bottle"". Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS080/document.
Pełny tekst źródłaThe main objective of this work was to develop non-targeted metabolomics analyses of bottled wines in order to decipher chemical informations from the time-related evolution of their composition. This original research was based on the hypothesis that, when analyzed, bottled wines would still hold chemical memories of envionmental parameters (vineyard management, oenological practices, climate, terroir…) at the moment of their elaboration, even after several years of ageing. A second hypothesis was that in order to anticipate the future evolution of the wine quality in terms of chemical composition, it is necessary to know what it was in the past. To that purpose, and for the first time in wine science, Fourier Transform Ion Cyclotron Resonance – Mass Spectrometry (FTICR-MS), Liquid Chromatography coupled with mass spectrometry (UPLC-Q-ToF-MS), Excitation Emission Matrix Fluorescence (EEMF) and multivariate statistics were used in combination. Methodological develoments revealed the advantage of coupling exact mass measurements by FTICR-MS to isomeric discrimination by UPLC-Q-ToF-MS in order to extend the range of detectable metabolites. Such tools were applied to the identification of ageing markers in vertical series of red and white wines from Burgundy, including very old wines (unknown vintages) considered as evolution end points, thus introducing the concept of verticalomics. The characterization of series of white wines from Burgundy (Chardonnay) revealed that chemical spaces specifically related to eonological practices (SO2 addition at pressing, settling level, and permeability of the stopper) could indeed be deciphered although the vintage signatures were confirmed to be the most significant. Similar experiments on Champagne wines (Chardonnay, and blends of Chardonnay, Pinot noir and Pinot Meunier) after the "prise de mousse" and the ageing "sur lattes" further highlighted the hormesis effect associated with the oxygenation of wine. Finally, non-targeted analyses of series of grape extracts and corresponding wines from different appelations – though elaborated by the same winemaker – revealed that terroir-related signatures could be indeed read in wines, in particular after a few years of bottle ageing. Altogether our results provide an unprecedented comprehensive description of the chemical composition of wine and its modification through ageing
Bahri, Syaiful. "In situ combustion for upgrading of heavy oil". Thesis, University of Salford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248917.
Pełny tekst źródłaAdewusi, Victor Adesegun. "Heavy oil recovery by forward in-situ combustion". Thesis, University of Bath, 1986. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370660.
Pełny tekst źródłaPaulson, Brandon. "Ex Situ Analyses of Non-Native Species Impacts on Imperiled Desert Fishes". Thesis, North Dakota State University, 2019. https://hdl.handle.net/10365/29890.
Pełny tekst źródłaNevada State Wildlife Grant
North Dakota State University. Environmental and Conservation Science Program
Desert Fish Council
Merchant, Akber. "In-situ fluidization for remediation of contaminated sand". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32966.
Pełny tekst źródłaThe effectiveness of the 'up-flow washing' technique for the removal of a water-soluble contaminant (CuSO4) from a saturated bed of sand was investigated for a vertical jet at jet velocities of 213 cm/s and 320 cm/s and jet insertion depths of 5.5 cm and 7.5 cm. Up-flow washing removed the contaminant from the sand bed. The cleaned region extended well beyond the boundary of the fluidized region as jet liquid leaked from the fluidized region and percolated through the fixed bed region. An approximate model for the leakage suggested that 10--20% of the jet liquid leaked from the fluidized region to the fixed bed region.
Indrijarso, Surat. "Development of pressurized thermogravimetry for in-situ combustion studies". Thesis, University of Salford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261489.
Pełny tekst źródłaRogozinski, Jeffrey David. "In-situ frequency-dependent electromagnetic sensing for monitoring physical and chemical attributes during chemical processing". W&M ScholarWorks, 2000. https://scholarworks.wm.edu/etd/1539623978.
Pełny tekst źródłaLöfgren, Martin. "Diffusive properties of granitic rock as measured by in-situ electrical methods". Doctoral thesis, KTH, Chemical Engineering and Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121.
Pełny tekst źródłaDiffusion into the rock matrix has been identified as one of the most important retention mechanisms for dissolved contaminants in fractured crystalline rock. In this thesis the diffusive properties of granitic rock, described by the formation factor, have been investigated by electrical methods. These methods are based on the Einstein relation between diffusivity and ionic mobility. Formation factors have been obtained both in the laboratory and in deep lying rock in-situ.
At present, two locations in Sweden, Forsmark and Oskarshamn, are undergoing site investigations for the siting of a repository for spent nuclear fuel. As a part of these investigations, the formation factor of the rock surrounding five, 1000 m deep boreholes has been investigated. More than 250 rock samples, taken from the bore cores, have been investigated in the laboratory and around 50 000 formation factors have been obtained in-situ. The results have been treated statistically and it appears that the formation factor is lognormally distributed. The mean and standard deviation of the obtained log-normal distributions vary from site to site, depending on the geology. For intact granitic rock, the obtained formation factors range between 2.2·10-7 and 2.5·10-2.
The results suggest that diffusion into open, but hydraulically non-conductive fractures may have a significant influence on radionuclide retention by way of increasing it. Therefore, the fractured rock formation factor was introduced in addition to the traditional rock matrix formation factor. The retardation capacity of crystalline rock is strongly associated with the pore connectivity. In this thesis, it is shown that the micropore network of granitic rock is connected on, at least, a metre scale in-situ.
Tripathi, Ashok Burton Goodwin David G. "In-situ diagnostics for metalorganic chemical vapor deposition of YBCO /". Diss., Pasadena, Calif. : California Institute of Technology, 2001. http://resolver.caltech.edu/CaltechETD:etd-09262005-143545.
Pełny tekst źródłaRai, Yugal. "In-situ interface chemical characterisation of a boundary lubricated contact". Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/12191/.
Pełny tekst źródłaDeshors, Marine. "Investigation of industrial enzymatic cocktail for deconstruction of wheat bran by combining in-situ physical and ex-situ biochemical analyses". Thesis, Toulouse, INSA, 2018. http://www.theses.fr/2018ISAT0042.
Pełny tekst źródłaEnzyme cocktails, such as Rovabio®, which is rich of hydrolytic enzymes are used as feed additives to favor degradation of non-starch polysaccharides present in wheat, a major feed in poultry industry. The deconstruction mechanism of wheat bran, part of the seed mainly composed of fiber, is still fairly unclear. This PhD aims to highlight these mechanisms using a multi-instrumented bioreactor that allowed to combine in-situ physical and ex-situ biochemical analyses. This multiscale approach stands as an alternative and original approach which is rarely considered in animal nutrition. This work highlights that Rovabio® action occurred in two concurrent process, namely fragmentation and solubilization phenomena which take place within the first 2 h after addition of the enzyme cocktail. It is then followed by a particle fragmentation which was not accompanied by any sugars solubilization. Thus, in spite of the abundant and very active hydrolytic enzyme activities in Rovabio®, the deconstruction of destarched wheat bran was however limited to 37% of w/w. At variance to Rovabio®, xylanase added alone was capable of solubilization activity (same final release of xylose and arabinose) but the fragmentation was much weaker by only disorganizing the fibrous network and hence led to particle disaggregation. Altogether, these results confirmed the importance of the enzyme mixtures which act in a synergistic manner to readily solubilize wheat bran. Our results also indicated that the limitation of Rovabio® action upon wheat bran degradation may come from physical inaccessibility of the substrate as it could be partially overcome by enhancing the substrate specific surface by a mechanical treatment and/or due to some missing or limiting enzyme activity as shown by a slight increase in solubilization following addition of some pectinases cocktails that are poorly represented in Rovabio®. Nevertheless, these complementary actions were still insufficient for complete hydrolysis of wheat bran. To conclude, this work draws attention to plant cell wall-deconstructing enzymes or active proteins which are able to attack the biomass minor structures and disorganize its network in order to increase substrate accessibility to enzymes that cleave backbone structures
Fujii, Yasuyo. "Chemical Analyses of Mosochiku(Phyllostachys pubescens Mazel) during Elongation Growth". Kyoto University, 1995. http://hdl.handle.net/2433/160856.
Pełny tekst źródłaKyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第6073号
農博第843号
新制||農||698(附属図書館)
学位論文||H7||N2796(農学部図書室)
UT51-95-D392
京都大学大学院農学研究科林産工学専攻
(主査)教授 岡村 圭造, 教授 佐伯 浩, 教授 島田 幹夫
学位規則第4条第1項該当
Taraboletti, Alexandra Anna. "Chemical and Metabolomic Analyses of Cuprizone-Induced Demyelination and Remyelination". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1498535047689141.
Pełny tekst źródłaZhang, Qiang. "Genetic and Expression Analyses of the 'Nkrp1-Clr' Gene Cluster". Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23271.
Pełny tekst źródłaAlenda, Aurélie. "Analyses quantitatives en spectroscopie infrarouge : l’AG-IR (Analyses Gravimétriques et spectroscopie InfraRouge) nouvel outil d’analyse pour les espèces adsorbées". Caen, 2010. http://www.theses.fr/2010CAEN2004.
Pełny tekst źródłaThe combination of qualitative and quantitative information in infrared spectra allowed understanding the grafting mechanism for octylphosphonic acid on aluminated silicas. In a second step, a new analytic tool, named AG-IR, was designed and tested, combining two complementary techniques: infrared spectroscopy and thermogravimetry. With this unique setup, the weight of the sample is directly measured during the spectroscopic measurement. The experiment can be performed under reduced pressure as well as under operando conditions (inside a working catalytic reactor). Two separate studies were performed. The first one, under vacuum, dealt with the adsorption of acetonitrile derivatives on HMFI zeolite. The second one, under flux, was the determination of integral molar absorption coefficients (denoted as epsilons) of adsorbed water on an H-Y zeolite during thermodesorption and on the interaction of co-adsorbed species. Several interesting results were obtained: the substitution of hydrogen atoms for chlorine atoms in acetonitrile strongly influences epsilon values for the nCºN vibration band, with epsilon decreasing with the number of substituted atoms. Epsilon for the dH2O vibration band depends on the hydration level of the zeolite. The (n+d)H2O vibration band is much less influenced, and this band is therefore recommended for the determination of the water content in the zeolite. Adsorbed water strongly influences the spectral response of adsorbed ammoniac, and the chemical environment of ammonium ions is deeply modified by co-adsorbed water
Mangesana, Nobathembu. "Developing a methodology for characterising in-situ viscosity profiles in tumbling mills". Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/16917.
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