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1
Lu, Thanh-Chi. "Structure superficielle des poudres de superalliages base nickel et mécanismes intervenant au cours de la densification." Paris, ENMP, 1987. http://www.theses.fr/1987ENMP0074.
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Role de la structure des surfaces de poudre avant la compaction isostatique a chaud et son evolution au cours de la consolidation. Influence des caracteristiques morphologiques et microstructurales sur la cinetique de consolidation et sur le comportement mecanique des materiaux compactes
2
Dezillie, Britta. "Étude de la tenue aux radiations de détecteurs de particules en silicium épitaxial pour leurs utilisaitons au LHC du CERN." Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10146.
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Dans les experiences futures dans le lhc de cern on veut utiliser des detecteurs de silicium de haute precision. Le composent hadronique influence le temps de vie des detecteurs. La tenue aux irradiations du silicium peut etre amelioree par l'etude des defauts. Cette etude implique l'addition des impuretes au silicium afin de former des centres de defauts qui sont actives d'une maniere electrique. Ceux ci controlent les parametres macroscopiques des echantillons. Les ingredients principales a examiner sont l'oxygene et le carbone parce qu'ils se comportent comme consommateurs des vacances et des interstitials. Un premier essai a introduire du ge dans le silicium a ete realise. Du materiel epitaxiale du type n de macom (us) qui contient dix fois plus d'oxygene que le float-zone (fz), montre une amelioration d'un facteur 2 a l'egard du fz. Les impuretes initiales au sein du materiel ont ete mesurees par sims et spectrometrie infrarouge (ir). Les etudes d'irradiations des detecteurs epitaxiales du type n et p avec une epaisseur de 200 m, produits par itme (pologne) avec differentes vitesses de croissance, sont reportees dans ce travail. Une comparaison de differents procedes comme l'implantation par ionisation et mesa a ete faite. La tenue aux irradiations des detecteurs de silicium epitaxials avec des resistivites initiales de 25 ohm cm a 10 kohm cm a ete comparee avec du fz standard. Les resultats sont presentes en terme de la variation du courant de fuite, la concentration de dopage effectif et la collection de charge en fonction de la fluence et le temps apres des irradiations proton en neutron jusqu'une fluence de 4. 5 10#1#4 p/cm#2.
3
BORDES, NICOLE. "Etude du dosage d'elements traces dans inp par activation avec des particules chargees; comparaison avec d'autres methodes de caracterisation." Toulouse, INSA, 1986. http://www.theses.fr/1986ISAT0035.
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Le phosphure d'indium (inp) est un materiau semiconducteur interessant pour ses proprietes electriques dans le domaine de la microelectronique et de l'optoelectronique. Dans le but de maitriser son elaboration et de mieux comprendre ses proprietes, il est necessaire de determiner la concentration des elements traces ou des dopants presents dans le materiau. Les methodes nucleaires d'activation par particules chargees sont actuellement parmi les plus sensibles pour l'analyse d'impuretes dans les materiaux, et surtout elles sont quantitatives. Les possibilites analytiques offertes par des protons de haute energie (superieure a 20 mev) ont ete etudiees et appliquees au dosage du chrome, cuivre, zinc et fer dans inp et in. Les sensibilites obtenues sont comprises entre 10**(13) et 8. 10**(13) a nontcm**(3). La presence de quelques impuretes legeres a egalement ete recherchee dans inp. Oxygene et carbone ont ete doses a l'aide de tritons de 6 mev et de deutons de 8 mev respectivement, avec une sensibilite de 4. 10**(13) a nontcm**(3) et 2. 10**(14) a nontcm**(3). Les protons de 13 mev ont permis le dosage du soufre dans l'indium avec une limite de detection de 2. 10**(15) a nontcm**(3). Le silicium a ete dose au moyen de tritons de 3 mev : une limite de quelques 10**(16) a nontcm**(3) a ete obtenue. Des comparaisons avec d'autres methodes de caracterisation telles que sims, ssms ont ete faites. Nous avons ensuite etudie d'une part la repartition de ces impuretes dans des lingots prepares par la methode czochralski sous encapsulant liquide (lec) et d'autre part suivi le transfert de ces impuretes au cours de la cristallogenese. Nous presentons enfin les caracteristiques electriques et cristallines des lingots d'inp etudies et nous avons essaye de les relier a la presence de ces elements
4
Li, Zhen. "Characterization of surface and layered films with cluster secondary ion mass spectrometry." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85794.
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Cluster secondary ion mass spectrometry (SIMS) analyses of layer-by-layer thin
films were performed to investigate the depth/volume of SI emission and accuracy of
the SI signal. The thin-layered samples were assembled by alternate adsorption of
polyethylenimine (PEI), polystyrene sulfonate (PSS), polydiallyldimethylammonium
chloride (PDDA) and clay nanoparticles. The films have controlled 3-D structure to
test the depth of secondary ion (SI) emission and evaluate planar homogeneity.
The SI emission depth is ~ 6-9 nm with 136 keV Au400
4+ (340 eV/atom) and 26
keV C60
+ (433 eV/atom) projectile impacts. The diameter of the SI emission area is ~
15 nm by assuming a semispherical emission volume. The SI yields oscillate with the
alternation of the compositions of the topmost layers, which was observed with small
cluster projectiles (CsICs+ and Au3
+) as well as with the large cluster projectiles (C60
+
and Au400
4+).
The SI signals of C- and CH- are enhanced in the presence of metal atoms in the
expanding plume. Recoiled C60 projectile fragments (m/z=12, 13, 36) are observed in
the SI mass spectra. Caution must be taken when monitoring the yields of such
carbon cluster ions from organic surfaces because their yields don't reflect the true
surface concentration.
The Au400
4+ projectile impacts produce abundant co-emission. The correlation
coefficient between the co-emitted SIs can be used to evaluate the planar homogeneity. The results show that the PSS layer is more uniform than the clay
layers.
The effect of alkali metal ion implantation on the nature and abundance of SI
emission was investigated on Cs+ or Na+ implanted glycine samples. The alkali metal
implantation induces surface damage and decreases the glycine molecular ion yields.
Glycine molecular ions and fragment ions (CN-, CNO-) are emitted from different
depths and locations of the emission volume. The same implanted glycine sample
analyzed with different cluster projectiles (Au400
4+ and C60
+) shows different trends in
the yields of molecular and fragment ions, which suggest a different mechanism of SI
emission with different projectile impacts. The Na+ beam induces more surface
damage compared with the Cs+ at equal impact energy.
5
Swinford, Richard William. "An AFM-SIMS Nano Tomography Acquisition System." PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3485.
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An instrument, adding the capability to measure 3D volumetric chemical composition, has been constructed by me as a member of the Sánchez Nano Laboratory. The laboratory's in situ atomic force microscope (AFM) and secondary ion mass spectrometry systems (SIMS) are functional and integrated as one instrument. The SIMS utilizes a Ga focused ion beam (FIB) combined with a quadrupole mass analyzer. The AFM is comprised of a 6-axis stage, three coarse axes and three fine. The coarse stage is used for placing the AFM tip anywhere inside a (13x13x5 mm3) (xyz) volume. Thus the tip can be moved in and out of the FIB processing region with ease. The planned range for the Z-axis piezo was 60 µm, but was reduced after it was damaged from arc events. The repaired Z-axis piezo is now operated at a smaller nominal range of 18 µm (16.7 µm after pre-loading), still quite respectable for an AFM. The noise floor of the AFM is approximately 0.4 nm Rq. The voxel size for the combined instrument is targeted at 50 nm or larger. Thus 0.4 nm of xyz uncertainty is acceptable. The instrument has been used for analyzing samples using FIB beam currents of 250 pA and 5.75 nA. Coarse tip approaches can take a long time so an abbreviated technique is employed. Because of the relatively long thro of the Z piezo, the tip can be disengaged by deactivating the servo PID. Once disengaged, it can be moved laterally out of the way of the FIB-SIMS using the coarse stage. This instrument has been used to acquire volumetric data on AlTiC using AFM tip diameters of 18.9 nm and 30.6 nm. Acquisition times are very long, requiring multiple days to acquire a 50-image stack. New features to be added include auto stigmation, auto beam shift, more software automation, etc. Longer term upgrades to include a new lower voltage Z-piezo with strain-gauge feedback and a new design to extend the life for the coarse XY nano-positioners. This AFM-SIMS instrument, as constructed, has proven to be a great proof of concept vehicle. In the future it will be used to analyze micro fossils and it will also be used as a part of an intensive teaching curriculum.
6
Graham, Daniel J. "Multivariate analysis of TOF-SIMS spectra from self-assembled monolayers /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/8003.
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Dickinson, Michelle. "Secondary ion mass spectrometry (SIMS) analysis of the arsenic-hyperaccumulator, Pteris vittata." Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422557.
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Gilmore, Ian Stuart. "Development of a measurement base for static secondary ion mass spectrometry." Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/11110.
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This work sets out a framework to provide a metrological basis for static SIMS measurements. This surface analytical technique has been is use for over thirty years but, because of the lack of an infrastructure, has not achieved its full potential in industry. To build this basis, the measurement chain is studied from the sample through to the detector and data processing. By understanding the effects of each link in the chain, repeatabilities are reduced by orders of magnitude to below 1%, the ion beam current and flux density are calibrated to better than 2%, ion beam damage in polymers is controlled and detection efficiencies calculated. Utilising these developments, a characterised and calibrated SIMS spectrometer is used to establish reference materials. An inter-laboratory study to assess the extent of spectrum variability between spectrometers was conducted involving over twenty laboratories worldwide. Analysis of the data gives the level of repeatability and reproducibility using current procedures. Repeatabilities for some laboratories are as good as 1% but many are at 10% and a few as poor as 80%. A Relative Instrument Spectral Response, RISR, is developed to facilitate the comparison of spectra from one instrument to another or library data. For most instruments reproducibilities of 14% are achievable. Additionally, the wide variety of ion beam sources and energies, presently in use, result in spectra that are only broadly comparable. A detailed study of these effects provides, for the first time, a unified method to relate the behaviour for all ion species and energies. A development of this work gives a totally new spectroscopy, known as G-SIMS or gentle-SIMS. Here, the static SIMS spectrum for a low surface plasma temperature is calculated which promotes those spectral intensities truly representative of the analysed material and reduces those caused by additional fragmentation and rearrangement mechanisms. The resulting GSIMS spectra are easier to identify and are interpreted more directly. This work provides the essential basis for the development of static SIMS. Future work will improve the consistency of library data so that the valid data for molecular identification can be uniquely extracted. The measurement base will be developed to meet the growing requirements for static SIMS analysis of complex organic and biomaterials.
9
Richter, Katrin. "Application of imaging TOF-SIMS in cell and tissue research /." Göteborg : Institute of Biomedicine, The Sahlgrenska Academy, Göteborg University, 2007. http://hdl.handle.net/2077/7447.
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Fu, Tingting. "3D and High Sensitivity Micrometric Mass Spectrometry Imaging." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS218/document.
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L'imagerie par spectrométrie de masse est d’un grand intérêt pour aborder les questions biologiques en fournissant simultanément des informations chimiques et spatiales. En particulier, la spectrométrie de masse baptisée TOF-SIMS est bien reconnue par sa haute résolution spatiale (< 1 μm), qui est essentielle pour révéler l'information chimique dans une zone submicronique. L'emploi croissant de cette technique dans la caractérisation des échantillons biologiques a bénéficié du développement de nouvelles sources d'ions d’agrégats. Cependant, les processus d'ionisation/désorption des analytes sous les impacts d’agrégats lourds sont encore mal compris. D'un autre côté, techniquement, les instruments TOF-SIMS commerciaux actuels ne peuvent pas fournir une résolution en masse suffisante ni une précision sur la détermination de la masse pour l'identification moléculaire, ce qui rend les analyses de systèmes biologiques complexes très difficiles, et nécessite le recours à la fragmentation MS/MS. Cette thèse vise à mieux comprendre la production d'ions sous l’impact d’agrégats lourds et à explorer la capacité MS/MS du spectromètre de masse par temps de vol combiné à l’imagerie ionique en utilisant le spectromètre de masse PHI nanoTOF II. Ce dernier point a été réalisé en cartographiant en haute résolution spatiale des métabolites importants de bois. Pour comprendre la production d'ions sous les impacts d’agrégats d'argon massifs, l'énergie interne des ions secondaires a été mesurée en utilisant la mesure du taux de survie d'une série d'ions benzylpyridinium. L'étude de diverses conditions d'impact (énergie, vitesse, taille des agrégats) a montré que la vitesse joue le rôle majeur dans la distribution d'énergie interne et la fragmentation moléculaire dans le régime à faible énergie par atome (E/n < 10 eV).Les capacités de la fragmentation MS/MS et d'imagerie en parallèle du spectromètre PHI nanoTOF II nouvellement conçu ont été évalués par cartographie MS/MS in situ des métabolites bioactifs rubrynolide et rubrenolide dans les espèces amazoniennes de bois Sextonia rubra, ainsi qu’une identification in situ des métabolites précurseurs. L'imagerie TOF-SIMS 2D et 3D a permis de localiser les cellules où cette biosynthèse s’effectue. Les résultats ont conduit à la proposition d'une voie possible de biosynthèse des deux métabolites. Pour étendre l'application de l'imagerie TOF-SIMS dans l'analyse chimique du bois, la distribution radiale des extraits de bois dans le duramen du bois du mélèze européen a également été étudiéeMass spectrometry imaging has been shown of great interest in addressing biological questions by providing simultaneously chemical and spatial information. Particularly, TOF-SIMS is well recognized for its high spatial resolution (< 1 µm) which is essential in disclosing chemical information within a submicron area. The increasing use of TOF-SIMS in characterizing biological samples has greatly benefited from the introduction of new cluster ion sources. However, the ionization/desorption of the analytes under impacts of large clusters is still poorly understood. On the other hand, technically, current commercial TOF-SIMS instruments generally cannot provide sufficient mass resolution or mass accuracy for molecular identification, making analyses of complex biological systems especially challenging when no MS/MS fragmentation is available. Thus this thesis is aimed to get a better understanding of ion production under cluster impacts, to explore the MS/MS capability of the parallel imaging MS/MS Spectrometer (PHI nanoTOF II), as well as to apply TOF-SIMS to map important wood metabolites with high spatial resolution.In order to understand ion production under impacts of massive argon clusters, internal energy distributions of secondary ions were measured using survival yield method which involves the analyses of a series of benzylpyridinium ions. Investigation of various impacting conditions (energy, velocity, cluster size) suggested that velocity of the clusters play a major role in internal energy distribution and molecular fragmentation in the low energy per atom regime (E/n < 10 eV). The MS/MS fragmentation and parallel imaging capabilities of the newly designed PHI nanoTOF II spectrometer were evaluated by in situ MS/MS mapping of bioactive metabolites rubrynolide and rubrenolide in Amazonia wood species Sextonia rubra. Then this parallel imaging MS/MS technique was applied to perform in situ identification of related precursor metabolites in the same tree species. 2D and 3D TOF-SIMS imaging were carried out to target the plant cells that biosynthesize rubrynolide and rubrenolide. The results led to the proposal of a possible biosynthesis pathway of these two metabolites. In addition, to expand the application of TOF-SIMS imaging in wood chemistry analysis, radial distribution of wood extractives in the heartwood of European larch was also investigated
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Franceschini, Marco José. "Projeto e construção de um sistema de vácuo dedicado a técnica SIMS." Universidade de São Paulo, 1997. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-01042014-160711/.
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O trabalho realizado teve como objetivo principal o projeto, a construção e os testes de um sistema de vácuo dedicado a técnica de Espectrometria de Massa do íon Secundário (SIMS), a ser utilizado na caracterização estrutural de heteroestruturas semicondutoras. O sistema (câmaras e conexões) foi totalmente desenvolvido nas dependências do IFSC-USP, sendo acoplado a este um conjunto de elementos comerciais, tais como: visores de Ultra-Alto Vácuo (UHV), medidores, canhão de íons, válvulas, bombas (mecânica, turbo e iônica) e espectrômetro de massa. Testes realizados mostraram que o sistema de vácuo principal (o sistema todo é composto por duas câmaras de vácuo: uma principal e uma de introdução) pode atingir pressões da ordem de 10-10 Torr, necessária para a implementação de técnicas de análise de superfície. Além disto, o sistema mostrou-se versátil para a troca de amostras (uso continuo) e de fácil operação. Além de instrumentação para UHV, os resultados obtidos são promissores no sentido de proporcionar uma economia nos custos para futuras aquisições de sistemas para analise de superfíciesThe principal purpose of this work was the project, construction and test of a vacuum system dedicated to Secondary Ion Mass Spectroscopy (SIMS), for the structural characterization of semiconductor heterostructures. All the system components were developed at the IFSC-USP, to which were connected commercial vacuum elements, such: Ultra-high Vacuum (UHV) visors, sensors, ion gun, vacuum pumps (mechanical, turbo and ionic) and mass spectrometer. The results showed that the main chamber (the system is composed by two chambers: main chamber and the load-look) is able to reach pressures of 10-10 Torr, important for surface analyses. Also the system showed versatility to change the samples and easy operation. The results for UHV instrumentation developed are promising, and these results can be used to decrease the cost of surface analysis systems which can be implemented in the future
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Popoola, Oludélé Olusègun. "Amorphisation et précipitation superficielles induites par implantation ionique dans les alliages NiTi équiatomiques : application aux propriétés tribologiques." Poitiers, 1988. http://www.theses.fr/1988POIT2292.
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Mise en evidence par microscopie electronique en transmission, spectrometrie sims et photoelectron d'une amorphisation superficielle et de la formation de fins precipites cristallins tin::(x) dans le cas d'une implantation, d'azote. Influence de la temperature et de la dose d'ion sur l'epaisseur de la couche. Correlation entre la microstructure d'implantation et les proprietes tribologiques. Le coefficient de frottement se trouve reduit et la resistance a l'usure se trouve amelioree de facon durable. L'initiation et la propagation des processus de degradation sont ainsi ralenties
13
Berrueta, Razo Irma. "Molecular imaging of mouse brain tissue using Cluster Time-of-Flight Secondary Ion Mass Spectrometry." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/molecular-imaging-of-mouse-brain-tissue-using-cluster-timeofflight-secondary-ion-mass-spectrometry(a350dc50-5337-4d32-a95c-24c617bbba97).html.
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ToF-SIMS imaging has been drawing attention due to the wide range of applications in the biological and biomedical fields. These applications include the acquisition of quantitative and qualitative data that ranges in scale from single cells to organs, image visualisation and interpretation of biomarkers for diagnosis and development of pharmaceutics. This study focused on molecular imaging of mouse brain tissue sections using cluster primary ion beams. First, cluster ion beams were applied to comparative background studies of biomolecules and brain total lipid extract. Enhancement of the secondary ion signal was observed using water-containing cluster primary ion beams, especially for [M+H]+ type secondary ions. Water-containing clusters were then used to acquire ToF-SIMS images from the cerebellar area of serial mouse brain tissue sections. Again, water-containing cluster beams produced the highest secondary ion yields in both grey and white matter, gaining a new level of insight into the lipid compositions of both types of tissue in the brain. A clinical case was also evaluated with ToF-SIMS imaging, using cluster beams for the analysis of 3xTg-AD mouse brain tissue. SIMS images were registered with fluorescence microscopy images for the in situ identification and co-localisation of the Amyloid-β plaques on the SIMS images. Spectra from regions of interest were analysed to identify possible ion fragments derived from the Aβ protein. The co-localisation of cholesterol was also studied from images obtained with different primary ion beams. The results presented show that cluster ToF-SIMS can be successfully applied to brain tissue imaging. New primary ion beam technologies allow us to acquire data with more useful secondary ion yield for clinical applications and biological research. Nevertheless, future technological improvements are required for specialised applications e.g. cellular imaging. Moreover, processing the data obtained is still challenging and more data processing tools are also needed for interpretation.
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Alturaifi, Huriyyah. "New capabilities for molecular surface and in-depth analysis with cluster secondary ion mass spectrometry." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/new-capabilities-for-molecular-surface-and-indepth-analysis-with-cluster-secondary-ion-mass-spectrometry(997f36ca-1bd6-42a0-a731-a4ddba055510).html.
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Energetic polyatomic cluster beams are increasingly used in materials processing and surface analysis applications. In secondary ion mass spectrometry (SIMS) such beams have previously been utilised to investigate the chemical distribution of organic molecules (polymers, biological molecules and pharmaceuticals etc). One important application is in organic electronics, where the depth-distribution of organic components is important in the device performance. Massive gas cluster ion beams (GCIBs) have produced more successful depth-profiles for organic electronic devices that smaller projectiles including SF5+ and C60+. However, further work is needed to investigate and optimise experimental parameters to deliver the necessary SIMS performance. This study focused on molecular depth profiling of organic insulator (PMMA) and semiconductor (PTAA and TIPS-pentacene) materials, in single and bi-layered combinations, utilising cluster SIMS, using C60+ and Arn+, at different temperatures and energies. In general, at room temperature, the best depth resolution was obtained, using large Ar-GCIBs of low energy per atom (E/n ~10 eV), in comparison with the smaller Ar-GCIBs or with C60+ beams at the same total impact energy. On materials which sputtering under C60+ bombardment, ion and neutral yields were greatest due to the higher E/n, compared with GCIBs. Data from PMMA show that the sputter yield under C60 and Arn projectiles conform to the published 'universal' dependence of Y/n to E/n. Depth profiling of the semiconductor compounds were unsuccessful, using C60+ projectiles. For depth profiles using large GCIB projectiles, an increase in the secondary ion yield was observed at the interface with the silicon substrate - a phenomenon which was not observed for the smaller projectiles. In general, the most successful depth profiles (i.e. more constant molecular and fragment secondary ion yields, observed at pseudo-steady-state regions) and best depth resolutions were obtained at cryogenic temperatures - conditions under which corresponding sputtering yields and secondary ion yields were suppressed.
15
Py, Matthieu. "A study of interfaces and nanostructures by time of flight mass spectrometry : towards a spatially resolved quantitative analysis." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00721832.
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Les dispositifs avancés pour la microélectronique intègrent divers matériaux et sont de dimensions nanométriques. Une connaissance précise de leur composition est requise pour améliorer leurs procédés de fabrication et comprendre leur comportement électrique. Le ToF-SIMS est un candidat intéressant, qui souffre cependant des effets de matrice et ne possède pas toujours une résolution spatiale suffisante. Le but de ce travail est de permettre une analyse quantitative et résolue en profondeur de matériaux et structures pour la microélectronique avancée à l'aide d'un ToF-SIMS standard. Cette étude porte sur SiGe, sur des matériaux à haute permittivité, des implants basse énergie et des matériaux organiques. Elle se concentre sur la préparation d'échantillons, l'optimisation des conditions expérimentales et le traitement de données pour mettre au point des protocoles d'analyse originaux dont la précision est évaluée grâce à d'autres techniques de caractérisation de pointe. Ces protocoles permettent d'améliorer la qualité des analyses en termes de résolution en profondeur, de précision et de reproductibilité
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Staněk, Jan. "Kvantitativní analýza matricových prvků metodami SIMS a LEIS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402575.
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This thesis studies comparison and connection of two spectrometric methods – low energy ion scattering spektrometry (LEIS) and secondary ion mass spectrometry (SIMS). SIMS method, despite its many positive qualities, suffers of so called matrix effect, which makes quantifiaction of data very difficult. LEIS method on the other hand is immune to this effect and so it’s suitable completion of SIMS method. As a convenient sample have been chosen AlGaN samples with various concentration of gallium and aluminium. In the first part of thesis is introduced physical essence of SIMS and LEIS method, experimental details and studied samples. In second part of the thesis there’s a description of measurements and comparison of data gained by each method.
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LEE, GUN-HWAN. "Contribution a l'etude de la caracterisation experimentale de l'adhesion par le test a la rayure : effet du traitement de surface avant depot." Nantes, 1989. http://www.theses.fr/1989NANT2015.
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Determination, par une analyse statistique deduite de la methode de weibull, de la charge critique moyenne comme parametre fiable de l'adhesion entre un depot et son substrat. Etude, dans le cas du couple cu/al etr de depots de sio::(2), de l'influence de la preparation de la surface du substrat sur le parametre d'adhesion
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Lei, Yu-Guo. "Surface morphology and chemical composition of polymers studied by AFM, XPS and ToF-SIMS /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?CENG%202002%20LEI.
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Briaud, Philippe. "Gravure ionique reactive des couches minces de tungstene et de tantale dans un plasma radiofrequence de sf::(6) : analyse du plasma et des surfaces gravees." Nantes, 1988. http://www.theses.fr/1988NANT2001.
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La presente etude porte sur la gravure seche de differents materiaux utilises pour la microelectronique. Nous avons etudie l'interaction entre un plasma rf de sf, a basse pression, et les couches minces de tantale et de tungstene. Pour cela nous avons effectue une analyse du plasma de sf::(6) avec une sonde de langmuir et un analyseur d'energie, et une analyse des surfaces apres gravure par spectrometrie de photoelectrons (esca ou xps), spectrometrie auger (aes) et spectrometrie de masse des ions secondaires emis par la surface (sims). Pour les deux regimes de frequences d'excitation utilises au cours de cette etude (25-125 khz) a basse frequence, et 13,56 mhz a haute frequence, on a trouve que le plasma de sf::(6) etait tres electronegatif (n>0,9 n::(+), n::(e) equiv. A 0,02 a 0,07 n::(+)). A basse frequence, l'energie des ions positifs est distribuee entre 0 et qv::(rf). La composante de basse energie (0-600 ev) a basse pression (10 mtorr) depend de la nature des electrodes. Une comparaison avec les distributions obtenues dans ar et cf, pour lesquelles l'influence des parametres "pression" et "puissance" est interpretee en considerant la decharge comme quasi continue, nous permet d'attribuer cette composante de basse energie aux ions crees dans la gaine par les electrons secondaires emis par les electrodes lorsqu'elles sont soumises au flux d'ions. A haute frequence, l'energie des ions positifs qui atteignent l'electrode-masse du reacteur est distribuee entre 0 et 50 ev. A basse pression, l'energie moyenne de la distribution est determinee par le potentiel plasma moyen v::(p). L'analyse in-situ des surfaces de ta et w, effectuee par spectrometrie auger et sims, apres gravure dans sf::(6), indique la presence d'une quantite notable de soufre sur la surface, quantite qui diminue lorsque l'echantillon est au contact de l'atmosphere ambiant. L'analyse de ces surfaces par spectrometrie de photoelectrons montre que les especes wf::(m)(m
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Ghumman, Chaudhry Amjad Ali. "Time-of-flight secondary ion mass spectrometry: new application for urinary stones analysis." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/8796.
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Huber, Anne-Katrin, Sven Ole Steinmüller, Eva Mutoro, Bjoern Luerßen, and Jürgen Janek. "In situ examination of Lanthanum Strontium Manganate (LSM) with Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS)." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-186860.
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Xia, Nan. "Time-of-flight secondary ion mass spectrometry (ToF-SIMS) characterization of conformation and orientation of adsorbed protein films /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/9869.
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Huber, Anne-Katrin, Sven Ole Steinmüller, Eva Mutoro, Bjoern Luerßen, and Jürgen Janek. "In situ examination of Lanthanum Strontium Manganate (LSM) with Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS)." Diffusion fundamentals 12 (2010) 52, 2010. https://ul.qucosa.de/id/qucosa%3A13889.
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Sansom, David Andrew. "A study of secondary ion mass spectrometry (SIMS) depth profiling of ultra-narrow doping structures in III-V semiconductors." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268022.
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Eccles, Adrian John. "The design, construction and characterisation of a microfocused ion/atom gun for use in secondary ion mass spectrometry (SIMS)." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334868.
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Jung, Seokwon. "Surface characterization of biomass by imaging mass spectrometry." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45906.
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Lignocellulosic biomass (e.g., non food-based agricultural resides and forestry wastes) has recently been promoted for use as a source of bioethanol instead of food-based materials (e.g., corn and sugar cane), however to fully realize these benefits an improved understanding of lignocellulosic recalcitrance must be developed. The primary goal of this thesis is to gain fundamental knowledge about the surface of the plant cell wall, which is to be integrated into understanding biomass recalcitrance. Imaging mass spectrometry by TOF-SIMS and MALDI-IMS is applied to understand detailed spatial and lateral changes of major components in the surface of biomass under submicron scale.
Using TOF-SIMS analysis, we have demonstrated a dilute acid pretreated poplar stem represented chemical differences between surface and bulk compositions. Especially, abundance of xylan was observed on the surface while sugar profile data showed most xylan (ca. 90%) removed from the bulk composition. Water only flowthrough pretreated poplar also represented difference chemistry between surface and bulk, which more cellulose revealed on the surface compared to bulk composition. In order to gain the spatial chemical distribution of biomass, 3-dimensional (3D) analysis of biomass using TOF-SIMS has been firstly introduced in the specific application of understanding recalcitrance. MALDI-IMS was also applied to visualize different molecular weight (e.g., DP) of cellulose oligomers on the surface of biomass.
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Raujol, Julie. "Complémentarité du TOF-SIMS et du MALDI-TOF pour l'étude de l'hypoxie dans un modèle in vitro et in vivo." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5506.
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L’oxygénation d’un tissu ou d’une cellule résulte d’un équilibre entre la disponibilité en oxygène et sa consommation. Un arrêt de la circulation ou des variations de la pression partielle en oxygène sont responsables d’une réduction de l’apport en oxygène induisant une réponse adaptative.L’objectif de ce travail a été de caractériser l’hypoxie de l’échelle cellulaire à tissulaire par la complémentarité de deux techniques d’imagerie par spectrométrie de masse (ISM) : La spectrométrie de masse à ionisation secondaire (SIMS) et l’ionisation/désorption par laser assistée par matrice (MALDI). L’ISM fournit la détection, l’identification et la distribution d’une variété d’espèces moléculaires endogènes et exogènes directement sur tissu sans marquage. Afin de caractériser l’hypoxie, un modèle in vitro de culture cellulaire en trois dimensions (sphéroïde) et un modèle in vivo d’accident vasculaire cérébral ont été utilisés.L’imagerie TOF-SIMS nous a permis de voir que la disponibilité réduite de l’oxygène au centre des sphéroides induit de profonds changements métaboliques. L’imagerie MALDI-TOF, quant à elle, a permis de visualiser la pharmacocinétique de différents traitements dans des sphéroides traités.Concernant l’étude sur l’accident vasculaire cérébral, l’imagerie SIMS et MALDI nous ont fourni une signature moléculaire de l’hypoxie tissulaire, apportant de nouvelles connaissances sur les changements physiopathologiques induits par la lésion tissulaire.La complémentarité de ces deux techniques d’imagerie permet donc une réelle synergie pour l’étude de l’hypoxie dans différents modèlesTissue or cells oxygenation results from a balance between oxygen availability and consumption. This availability is determined by the amount of oxygen carried by the blood irrigating the tissue and its diffusion capacity through the cell membranes. The interruption of blood flow or variations in the oxygen partial pressure are responsible for a reduction of oxygen intake that induces an adaptive response.The aim of my work is to characterize the hypoxia from cellular to tissue-level via the complementarity of two mass spectrometry imaging (MSI) methods: the Secondary Ion Mass Spectrometry (SIMS) and Matrix-Assisted Laser Desorption and Ionization (MALDI). MSI has the potential to provide detection, identification and distribution of a variety of different endogenous and exogenous molecular species directly from the tissue without labelling. Here we combine them to characterize hypoxia in vitro on a 3D cell culture system (spheroid) and in vivo using ischemic rat model.We have shown via TOF-SIMS imaging that reduced availability of oxygen to the center of spheroids induces profound metabolic changes. MALDI-TOF imaging helped to visualize the pharmacokinetics of different treatments in treated spheroids.Concerning the ischemic stroke, MSI provides a molecular signature of hypoxia in tissue, which could bring new insights into the pathological changes induced by the tissue injury.The complementarity of these two imaging techniques allows real synergy for the study of hypoxia in different models
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Siljeström, Sandra. "Single fluid inclusion analysis using ToF-SIMS : Implications for ancient Earth biodiversiy and paleoenvironment studies." Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-54909.
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When and how life first emerged on the Earth is an area of intense research. Signs of the first life on Earth, including morphological fossils, are scarce and hard to interpret. An alternative approach is to study organic biomarkers, which are molecular fossils commonly considered as bona fide biosignatures. The main objective of the project is to develop an approach for analysis of single oil-bearing fluid inclusions and most importantly the detection of organic biomarkers in these inclusions. Analysis of oil-bearing fluid inclusions is advantageous since the inclusions may provide an uncontaminated sample source of Precambrian hopanes and steranes, which are key biomarkers for tracing the early evolution of life on Earth. Due to the presence of several inclusion generations, single inclusion analysis is desired in order to constrain biomarkers to specific inclusions. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) could be an excellent tool for analysis of these types of samples. The development of the approach for analysis of single oil-bearing inclusions was done in a two-step process; i) a number of crude oils were analysed with ToF-SIMS and gas chromatography mass-spectrometry (GC-MS) to facilitate interpretation of ToF-SIMS spectra of these types of samples and, ii) a procedure that combines micrographs with ion etching and ToF-SIMS analysis was developed for analysis of inclusions. The feasibility of the technique was demonstrated for oil inclusions from the Siljan impact crater in which hopanes and steranes where detected. Single oil-bearing fluid inclusions trapped in mid-Proterozoic sandstones from Northern Australia were subsequently analyzed, and steranes and hopanes were detected in these inclusions. If applied on older inclusions this approach may help answer some of the questions regarding the emergence and evolution of life on Earth, and if applied on extraterrestrial samples, also the possibility of life on other planets and moons.Livets uppkomst och tidiga utveckling på jorden är ett hett forskningsfält. Hur och när livet och dess olika domäner (arkéer, bakterier och eukaryoter) uppstod på jorden är fortfarande oklart vilket beror på att de första tecknen på liv, vilka inkluderar morfologiska fossil, spårfossil och isotoper, är få och svåra att tolka. Ett alternativt sätt att studera det tidiga livet är att studera organiska biomarkörer som är organiska molekyler som anses unika för liv. Huvudmålet med projektet är att utveckla en metod som kan detektera organiska biomarkörer i enskilda oljebärande vätskeinneslutningar. Vätskeinneslutningar, som är små mängder vätska (picoliter) infångad in en sten, är intressanta då de är en potentiell provkälla för prekambriska (äldre än 500 miljoner år) biomarkörer, som hopaner och steraner, vilka används för att utforska livets tidiga utveckling på jorden. Analys av enskilda inneslutningar är emellertid oftast nödvändigt för att kunna tidsavgränsa biomarkörer. På grund av att de flesta inneslutningar är små (10 µm i diameter) är det inte möjligt att analysera en enskild vätskeinneslutning med standardtekniken gaskromatografi-masspektrometri (GC-MS). Time-of-flight secondary ion mass spektrometri (ToF-SIMS) med sin höga känslighet, höga massupplösning och kapacitet för 2D-representation av analysdata och djupprofilering av prover är en utmärkt teknik för analys av enskilda inneslutningar. Metoden för analys av enskilda inneslutningar utvecklades i två steg. Först analyserades ett antal råoljor med ToF-SIMS och GC-MS för att underlätta förståelsen av ToF-SIMS-spektra från dessa typer av prover. Därefter utvecklades en metod som bestod av mikroskopering för att lokalisera inneslutningen, jonetsning för att öppna inneslutningen och ToF-SIMS analys av det exponerade innehållet. Metoden testades framgångsrikt på enskilda inneslutningar i hydrotermala vener av flusspat och kalcit i ordovicisk (488-443 miljoner år sedan) kalksten. Därefter användes den utvecklade metoden för att analysera enskilda vätskeinneslutningar i 1,43 miljarder år gammal sandsten från norra Australien, i vilka hopaner och steraner detekterades. De detekterade steranerna visar att trots att havet under denna tid var syrefritt existerade det lokala syrerika miljöer där eukaryoter kunde överleva. Om den utvecklade metoden används på ännu äldre inneslutningar, vilka har daterats till 3,2 miljarder år, kan den komma att svara på några de mest fundamentala frågorna kring livets uppkomst och tidiga utveckling. Om metoden används på utomjordiska prover kan den svara på frågan om det finns liv på andra planeter eller månar.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Submitted.
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Vanbellingen, Quentin. "Imagerie de substances naturelles par spectrométrie de masse." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS172/document.
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Cette thèse a été consacrée à l’amélioration de méthodes en imagerie par spectrométrie de masse, et à leur utilisation pour l’analyse in situ de substances naturelles. Une première partie a été consacrée à développer une nouvelle méthode permettant d’acquérir en imagerie TOF-SIMS des images avec une résolution de 400 nm tout en préservant la résolution en masse. Pour cela, une extraction retardée des ions secondaires a été caractérisée et optimisée. Une seconde partie a eu pour objectif d’étudier le phénomène de duraminisation d’un arbre tropical de l’espèce Dicorynia guianensis, qui est l’un des plus exploités en Guyane française et dont le duramen est réputé être imputrescible. Les images par spectrométrie de masse TOF-SIMS enregistrées avec la méthode développée ont montré à l’échelle sub-micrométrique les changements métaboliques s’opérant autour de la zone de transition, où s’opère la duraminisation. Les techniques TOF-SIMS et MALDI-TOF ont ensuite été utilisées pour l’analyse d’une surface sur laquelle ont crû deux souches microbiennes en compétition. Les deux souches ont été extraites d’un if japonais (Cephalotaxus harringtonia), l’une étant un champignon endophyte (Paraconiothyrium variabile) et l’autre une bactérie pathogène à ce conifère (Bacillus subtilis). Les résultats ont montré que le champignon était capable d’hydrolyser les surfactines produites par la bactérie. Enfin, les imageries par spectrométrie de masse MALDI-TOF et TOF-SIMS sont deux méthodes de choix pour l’étude de modèle in vitro de ce qui pourrait se produire in vivoThis thesis was devoted to the improvement of mass spectrometry imaging methods, and to their use for in situ analysis of natural substances. The first part of this thesis has been dedicated to the development of a new acquisition mode in TOF-SIMS imaging able to acquire images with a high spatial resolution of 400 nm while keeping a good mass resolution. For that, a delayed extraction of the secondary ions has been characterized and optimized. Then, a second part has been dedicated to the study of heartwood production in a tropical species named Dicorynia guianensis. This species is one of the most exploited in French Guiana for its heartwood which exhibits a good durability. Metabolic changes are shown by sub-micrometric resolution ion images recorded in and around the transition zone, where the heartwood formation occurs. Then, TOF-SIMS and MALDI-TOF have both been used to analyse the surface of a bacterial competition. Species have been isolated from a Japanese conifer (Cephalotaxus harringtonia), from which the stains are an endophitic fungi (Paraconiothyrium variabile) and a pathogenic bacteria of the conifer (Bacillus subtilis). The results have shown that the fungus is able to hydrolyze surfactines produced by the bacteria during the competition. Furthermore, both the MALDI-TOF and the TOF-SIMS mass spectrometry imaging are methods of choice to study in vitro models of what could happen in vivo
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Suzuki, Noriaki. "Applications of time-of-flight secondary ion mass spectrometry (TOF-SIMS) and x-ray photoelectron spectroscopy (XPS) to study interactions of genetically engineered proteins with noble metal films /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/10618.
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Veith, Lothar [Verfasser]. "Optimization and application of Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) for the detection of nanomaterials in tissue thin sections / Lothar Veith." Siegen : Universitätsbibliothek der Universität Siegen, 2019. http://d-nb.info/1180026837/34.
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Steinmüller, Sven Ole, Halit Aydin, Alexander Rein, and Carsten Korte. "Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) 18 O-tracer investigations on interface diffusion in Y 2 O 3 /YSZ multilayer systems." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-186982.
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Steinmüller, Sven Ole, Halit Aydin, Alexander Rein, and Carsten Korte. "Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) 18 O-tracer investigations on interface diffusion in Y 2 O 3 /YSZ multilayer systems." Diffusion fundamentals 12 (2010) 55, 2010. https://ul.qucosa.de/id/qucosa%3A12839.
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Tian, Hua. "Visualisation and profiling of lipids in single biological cells using time-of-flight secondary ion mass spectrometry." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/visualisation-and-profiling-of-lipids-in-single-biological-cells-using-timeofflight-secondary-ion-mass-spectrometry(c36313be-4ffd-4809-b5c9-8fbe1f720bd1).html.
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Imaging Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) has been developed to perform 2D imaging and depth profiling of biological systems with micron or submicron scale lateral resolution, which can be attributed to the advent of polyatomic ion beam particularly C60+ and new concept of ToF-SIMS instrument, the J105 3D Chemical Imager (J105). These recent advances in ToF-SIMS have opened a new dimension for biological analysis. In this study, 2D and 3D imaging have been performed on two biological systems, Xenopus laevis (X. laevis) zygote/embryo and murine embryonic fibroblasts NIH 3T3 BXB-ER cells to explore the capability of ToF-SIMS to handle the biological samples with extreme topography and high resolution depth profiling of microdomains, which still represent major challenges for the ToF-SIMS. The study on X. laevis embryo explored the capability of ToF-SIMS to handle spherical samples (approx. 1-1.2 mm in diameter), identify lipid species in mixtures of lipid extraction from the zygotes and image of an intact embryo in 2D/3D during dynamic biological events, e.g., fertilisation and early embryo development. For the first time the J105 and conventional BioToF-SIMS instrument were employed for the study of developmental biology. The major classes of lipid were identified through multiple lipid assay in a single analytical run using ToF-SIMS. Topography effects of the embryo were assessed through imaging a single intact zygote/embryo that revealed secondary ions loss at the edge of the single cell. However, the topography effects on the mass resolution could be minimised using the J105. Moreover, in situ lipid profiling of the zygote revealed different lipid compositions and intensities on the membrane of the animal and vegetal hemispheres. Furthermore, high resolution imaging and depth profiling that performed on a single intact cell in a time course study visualised the egg-sperm fusion sites on the membrane of the zygote 10 min post-insemination and lipids arrangement on the membrane of the embryo through the early development stages. Subcellular signalling upon the fertilisation was also spatially located on the serial cryosections of a single zygote. With the NIH 3T3 BXB-ER cells, the study firstly adopted a finely focused C60+ beam to track morphological changes and rearrangement of subcellular organelle mitochondria (0.5-2 µm) in response to the activation of Raf/ERK (extracellular signal regulated kinase) pathway using the J105. The SIMS images of the unlabelled cells showed the shifting of membrane distribution and nuclei shrinking following Raf/ERK activation. The mitochondria fluorescence probe within the cells were located 3-dimensionally using confocal microscopy and ToF-SIMS, which revealed the distribution pattern of condensing in the two sides of the nuclei following the Raf/ERK activation. Coupled with scanning electron microscopy (SEM), the three imaging modes showed good agreement in cellular morphological changes and subcellular mitochondrial rearrangement without or following Raf/ERK activation, demonstrating an integrated approaching to study the biological processes at subcellular dimension.
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Moore, Katie Louise. "High resolution secondary ion mass spectrometry analysis of trace elements in cereal grain and roots." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:ab4f4a19-baca-48a7-af54-b9c5d87f3b7a.
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This thesis presents information on the subcellular localisation of two important trace elements, selenium and arsenic, in wheat, rice and rice roots for what is believed to be the first time. The general aim of this work was to illustrate the potential of using physical science techniques to solve biological problems. High resolution secondary ion mass spectrometry was undertaken using the CAMECA NanoSIMS50 with a sensitivity down to ppm concentrations and a lateral resolution of less than 100 nm. Selenium in wheat grain was found to be distributed across both the bran layer and the endosperm region with Se-rich hotspots found in the aleurone cells and a higher intensity of Se in the subaleurone region. Arsenic in rice grain was found in two key regions. In grains with high As and high dimethylarsinic acid (DMA) content, As was predominantly localised to the subaleurone region yet in lower concentration, hydroponically grown As(III)-treated grains the As was only localised to the aleurone layer near the ovular vascular trace (OVT). A combined NanoSIMS and S-XRF experiment revealed As hotspots near the OVT. A combination of high pressure freezing, high resolution secondary ion mass spectrometry and TEM was used to localise As in the roots of rice plants revealing a contrasting subcellular distribution of As and Si in the roots even though arsenite and silicic acid are transported across the plasma membranes by the same transporters. Fe plaque forms only on the root epidermis and was shown to be a strong sink for As. Colocalisation of S with As in the vacuoles of the endodermis, pericycle and xylem parenchyma supports the notion that As is stored as arsenite-phytochelatin complexes in the roots while Si is localised in the endodermis cell walls and is not strongly affected by the Lsi2 mutation.
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Bradley, Shawn Todd. "Investigation of AlGaN films and nickel/AlGaN Schottky diodes using depth-dependent cathodoluminescence spectroscopy and secondary ion mass spectrometry." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1078329692.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xxii, 182 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Leonard J. Brillson, Dept. of Electrical Engineering. Includes bibliographical references (p. 173-182).
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Dong, Qian. "Studies of transport in some oxides by gas phase analysis." Licentiate thesis, Stockholm, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-363.
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Anxionnaz, Françoise. "Microstructure et composition chimique de composites sic/si : :(3)n::(4)." Paris 6, 1987. http://www.theses.fr/1987PA066141.
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On etudie par microscopie (meb, met, eels, edx) et par analyse par sonde ionique (sims) les composites prepares par impregnation de fibres de sic par depot chimique en phase vapeur de si::(3)n::(4) ou sic. On etudie l'influence du substrat sur la microstructure des depots, puis on caracterise la microstructure et la composition chimique de fibres elementaires de sic revetues par cvd de c et de sic. L'analyse des fibres revetues et tout particulierement de l'interface fibre/matrice montre la complementarite des methodes eels et sims pour caracteriser les composites a fibres longues
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BENSOUSSAN, SERGE. "Deformations dans les heterostructures epitaxiees sur des substrats semiconducteurs iii-v : etude experimentale par diffraction de rayons x et simulation sur ordinateur." Paris 6, 1986. http://www.theses.fr/1986PA066374.
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La distribution de deformation a l'interface entre une couche epitaxique d'un compose tertiaire (arseniure de al et ga par exemple) et un support semiconducteur iii-v a pu etre mise en evidence et mesuree a l'aide, essentiellement, de la diffraction d'une onde rx plane ou pseudo-plane. Etude de la sensibilite de la methode a un etalement de l'interface en fonction de l'epaisseur de la couche et de son desaccord avec le support. Simulation sur ordinateur du profil de reflexion des jonctions abruptes et etalees. Application a divers echantillons et au cas des structures multicouches et des superreseaux
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Lee, Joanna L. S. "Time-of-flight secondary ion mass spectrometry - fundamental issues for quantitative measurements and multivariate data analysis." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:f0e4b8ff-f563-429e-9e71-9c277a5139c4.
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Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a powerful technique for the analysis of organic surfaces and interfaces for many innovative technologies. However, despite recent developments, there are still many issues and challenges hindering the robust, validated use of ToF-SIMS for quantitative measurement. These include: the lack of metrology and fundamental understanding for the use of novel cluster primary ion beams such as C60n+ and Ar2000+; the need for validated and robust measurement protocols for difficult samples, such as those with significant micron scale surface topography; the lack of guidance on novel data analysis methods including multivariate analysis which have the potential to simplify many time-consuming and intensive analyses in industry; and the need to establish best practice to improve the accuracy of measurements. This thesis describes research undertaken to address the above challenges. Sample topography and field effects were evaluated experimentally using model conducting and insulating fibres and compared with computer simulations to provide recommendation to diagnose and reduce the effects. Two popular multivariate methods, principal component analysis (PCA) and multivariate curve resolution (MCR), were explored using mixed organic systems consisting of a simple polymer blend and complex hair fibres treated with a multi-component formulation to evaluate different multivariate and data preprocessing methods for the optimal identification, localisation and quantification of the chemical components. Finally, cluster ion beams C60n+ and Ar500-2500+ were evaluated on an inorganic surface and an organic delta layer reference material respectively to elucidate the fundamental metrology of cluster ion sputtering and pave the way for their use in organic depth profiling. These studies provide the essential metrological foundation to address frontier issues in surface and nanoanalysis and extend the measurement capabilities of ToF-SIMS.
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Madaan, Nitesh. "Synthesis and Characterization of Complex Molecular Assemblies on Surfaces." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/5748.
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The research presented in this dissertation is focused on the construction of complex molecular structures on planar gold and silicon dioxide surfaces using a variety of surface modification techniques, along with thorough surface characterization at each modification step. The dissertation is structured into six separate chapters. In Chapter 1, an introduction to the importance and implications of molecular level surface modification, commonly employed surface modification methods, and available surface characterization techniques is presented. Chapter 2 shows applications of novel methodologies for the functionalization of gold surfaces using alkane dithiol self-assembled monolayers and thiol-ene click chemistry. The resulting functionalized gold substrates demonstrate higher chemical stability than alkanethiol self-assembled monolayers alone and allow spatially controlled functionalization of gold surfaces with light. In Chapter 3, work on tunable hydrophobic surfaces is presented. These surfaces are prepared using a combination of organosilane chemistry, layer-by-layer polyelectrolyte deposition, and thiol-ene chemistry. These hydrophobic surfaces demonstrate high mechanical and chemical stability, even at low pH (1.68). The pinning of water droplets could be tuned on them by the extent of their thermal treatment. Comprehensive surface characterization using X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), spectroscopic ellipsometry, atomic force microscopy, and water contact angles was carried out on the molecular assemblies prepared on gold and silicon dioxide surfaces. Chapters 4 and 5 are focused on the application, data interpretation, and enhancement in sensitivity of different surface characterization methods. In Chapter 4, XPS, ToF-SIMS, and principal components analysis are used to probe a real world corrosion-type problem. This systemic study showed the destruction of a protective coating composed of a nitrilotris(methylene)triphosphonic acid by a low-intensity fluorine plasma. In Chapter 5, enhancement in ToF-SIMS signals is shown via bismuth metal deposition. These surfaces are also probed by spectroscopic ellipsometry using the interference enhancement method. Finally, Chapter 6 concludes this dissertation by describing possible future work.
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Robinet, Laurianne. "The role of organic pollutants in the alteration of historic soda silicate glasses." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/1475.
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The stability of glass is linked to its composition and the atmosphere controls its alteration. The organic pollutants emitted by wooden showcases play a role in the alteration of historic glasses. This study examines the effects of acetic acid, formic acid and formaldehyde on objects from the National Museums of Scotland and on replica glasses aged artificially, all with a soda silicate composition. Composition was determined by electron microprobe and analytical decomposition of the Raman spectra was used to establish correlations between glass structure and composition. This allowed interpretation of the structural variations between bulk and altered glass. The structure of the glasses altered by pollutants is characteristic of an alteration by selective leaching, with transformation of the silicates linked to alkali into silanols, which subsequently underwent condensation reactions to form a more polymerised structure. The SIMS concentration profiles of glass aged in artificial and real atmospheres were used to follow the alteration evolution as a function of time, humidity and pollutant concentration. The water film formed by the humidity at the surface and its acidity control the alteration by leaching of alkali and hydration of the glass. Formaldehyde does not act on the leaching reaction while acids accelerate and amplify it. In mixed polluted atmosphere, formates compounds always predominate in the film even at low formic acid concentration. The humidity and temperature fluctuations in museums maintain the leaching reaction. Knowledge of the harmful effect of organic acid pollutants in the alteration of soda silicate glasses will help improve their conservation.
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Aguir, Khalifa. "Nouvelle methode de pulverisation reactive : synthese et caracterisation de films minces de ga::(x)as::(1-x) amorphe hydrogene." Toulouse 3, 1987. http://www.theses.fr/1987TOU30174.
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Ce procede de synthese utilise pour la premiere fois fait intervenir simultanement des processus competitifs de depot tels que la pulverisation cathodique de ga et la decomposition de l'arsenic dans une decharge luminescente. La caracterisation optique et electrique du plasma a permis de maitriser la zone transitoire et la composition des depots. La nature amorphe des materiaux synthetises et leur structure ont ete mises en evidence par microdiffraction electronique et diffusion raman. Mise en evidence de l'homogeneite par spectrometrie sims. Pour des depots realises a temperature ambiante, la conductivite et la bande interdite optique varient avec la composition des films. Les films obtenus a des temperatures de support plus elevees ont des comportements optiques et electriques differents
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Zindine, El Mostafa. "Etude de la résistance à la corrosion de quelques métaux et alliages susceptibles d'être utilisés en connectique sans traitement de surface préalable." Besançon, 1987. http://www.theses.fr/1987BESA2029.
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Etude du comportement mecanique et de la resistance a la corrosion de certains metaux et alliages susceptibles d'etre utilises pour la fabrication de connecteurs sans revetement protecteur. Des alliages a base de nickel, a base de cuivre et a base de cobalt ont ete testes dans des milieux d'essais industriels (h::(2)s et/ou h::(2)s+so::(2)). La nature des produits de corrosion formes ete analysee par reduction electrochimique, diffraction des rx, microsonde de castaing et spectrometrie xps. Les resultats ont ete compares avec ceux obtenus par polarisation des echantillons dans une solution aqueuse de na::(2)s. L'influence des etats thermomecaniques et l'effet des elements d'addition a ete examinee
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Asplet, William. "Etude des interactions entre les défauts lacunaires et les solutés Y,O, Ti pour mieux comprendre leur rôle dans la formation des nanoparticules d'oxydes dans les aciers ODS." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2056/document.
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Cette thèse est dédiée à l’étude des interactions entre les défauts lacunaires et les solutés (Y, Ti, O) pour mieux comprendre la formation des nanoparticules d’oxyde dans les aciers ODS (Oxide Dispersion Strengthened). Ces aciers sont envisagés comme matériau de structure dans la prochaine génération de réacteurs nucléaires fission et fusion. Leurs bonnes propriétés reposent essentiellement sur une répartition homogène de nanoparticules (YxTiyOz) de très faible taille. Cependant, l’obtention de cette répartition n’est pas encore maitrisée et le mécanisme de formation de ces nanoparticules n’est pas encore bien défini. Des modèles théoriques montrent que la présence de lacunes pendant l’étape de broyage pourrait impacter la formation de ces nanoparticules. Cette étude fait suite à la thèse de C. He et apporte de nouveaux résultats et de nouvelles interprétations et conclusions. Des implantations avec des ions Y, Ti, O ont été réalisées afin de simuler l’étape de broyage de ces aciers ODS. Elles ont permis d’introduire des défauts et les solutés désirés dans la matrice de fer α. Nous avons ensuite étudié les interactions entre les solutés et les défauts générés dans la matrice. La nature des défauts induits a été étudiée en fonction de l’ion implanté et de traitements thermiques après implantation par spectroscopie d’annihilation de positons (PAS) et corrélée avec les profils en profondeur des solutés obtenus par spectrométrie de masse des ions secondaires (SIMS). Les caractéristiques d’annihilation de certains défauts encore inconnues ont pu être déterminées. Les mesures SIMS ont montré que le titane ne migre pas entre 100 et 450°C et que l’oxygène présente un comportement complexe de migration et de piégeage dépendant de la température et de la microstructure des matériaux. Les résultats PAS montrent que les implantations ioniques conduisent à la formation de clusters lacunaires, de complexes lacunes-solutés et de dislocations dont la proportion change en fonction de la profondeur et de la nature de l’ion implanté. Les clusters de lacunes Vn et les dislocations sont détectés au-delà du pic d’implantation avec une fraction plus importante pour les dislocations indiquant que les défauts ont pu migrer pendant l’implantation. La proportion des complexes lacunes-solutés est maximale dans la zone d’arrêt des ions. Elle est en accord avec les énergies de liaison théoriques des complexes lacunes-soluté. La nature et la distribution des défauts formés évoluent en fonction de la température de recuit. Les clusters lacunaires Vn disparaissent entre RT et 300°C alors que les dislocations sont éliminées à partir de 400°C. Des phases oxydes sont détectées pour des recuits à 500 et 550°C en lien avec la contamination en oxygène. Des défauts dont la nature est non identifiée ont été mis en évidence pour des recuits réalisés entre 300 et 400°C dans les implantations O, Y et Y+OThis PhD thesis is dedicated to the study of interaction between vacancies and Y, Ti,O solutes for a better understanding of formation of oxide nanoparticles in ODS steel (Oxide Dispersion Strengthened). These ODS steels are considered as structural material for the next generation of fission and fusion nuclear reactors. Their good properties are induced by the fine dispersion of low size oxide nanoparticles. However, obtaining this distribution is not mastered and atomic scale clustering is not yet defined. Furthermore, it was shown by theoretical models that the presence of vacancy during mechanical alloying could affect the formation of these nanoparticles. This study follows upon on a previous study made by C.He, and bring new results, new interpretation and conclusions. Some implantations with Y, Ti, O ions with several energy have been made in order to simulate the mechanical alloying step used for ODS steel fabrication. Theses irradiations have induced defects and solutes into the iron matrix. Then we characterized samples using positron annihilation spectroscopy (PAS) and secondary ion mass spectrometry (SIMS). The nature of defects was studied according to nature of the implanted ion and the annealing temperature by PAS and correlated to depth profiles of solutes obtained by SIMS. Annihilation characteristics of some defects still unknown were able to be determined thanks to positron lifetime measurements. SIMS analysis showed that titanium doesn’t migrate for annealing experiments between 100°C and 450°C and that oxygen show a complex behavior of migration and trapping dependent on the microstructure of the material. PAS results show that ionic implantations produce vacancy clusters, dislocations and solutes-vacancies complex. Their proportion changes as a function of depth and nature of these irradiations. Vacancy clusters and dislocations are detected deeper than the implantation peak with a higher fraction for the dislocations indicating that the defects were able to migrate during implantations. The fraction of vacancy-solutes complexes is the highest in the ion stopping zone and is in a good agreement with the theoretical binding energy of vacancies-solutes complex. The nature and the distribution of the defects evolve according to the annealing temperature. Vacancy clusters disappear between RT and 300°C while the dislocations are eliminated from 400°C. Oxide phases are detected for annealing at 500 and 550°C in relation with the oxygen contamination during these annealings. Some defects which the nature is not yet identified were highlighted for annealing between 300 and 400°C for Y, O and Y+O irradiations
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Botling, Taube Amelie. "Molecular and epidemiological studies on eyes with pseudoexfoliation syndrome." Doctoral thesis, Uppsala universitet, Oftalmiatrik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-260714.
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Pseudoexfoliation (PEX) syndrome is an age-related condition characterized by the production and accumulation of extracellular fibrillary material in the anterior segment of the eye. PEX predisposes for several pathological conditions, such as glaucoma and complications during and after cataract surgery. The pathogenesis of PEX is not yet fully understood. It is multifactorial with genetics and ageing as contributing factors. We aimed to study the proteome in aqueous humor (AH) in PEX in order to increase the knowledge about its pathophysiology. Therefore, we developed sampling techniques and evaluated separation methods necessary for analyzing small sample volumes. Other objectives were to study the lens capsule in eyes with PEX regarding small molecules, and to investigate the association between PEX and cataract surgery in a population-based 30-year follow-up study. Samples of AH from eyes with PEX and control eyes were collected during cataract surgery. In pooled, and individual samples, various liquid based separation techniques and high resolution mass spectrometry were utilized. For quantitation, various methods for labeling, and label free techniques were applied. Lens capsules were collected from some of the patients, and analysed by imaging mass spectrometry. A cohort of 1,471 elderly individuals underwent a comprehensive ophthalmological examination at baseline. Medical information was obtained by questionnaires, and from medical records. Incident cases of cataract surgery were identified by review of medical records. In the initial study, several techniques were explored for protein detection, and a number of proteins were identified as differentially expressed. In the individually labelled samples, changes in the proteome were observed. Eyes with PEX contained higher levels of proteins involved in inflammation, oxidative stress, and coagulation, suggesting that these mechanisms are involved in the pathogenesis in PEX. The levels of β/γ-crystallins were significantly increased in PEX, which is a novel finding. In the lens capsules from individuals with PEX, changes in the lipid composition was observed with time-of-flight secondary ion mass spectrometry. These changes remain to be elucidated. By multivariate analysis, lens opacities were the first, and PEX the second most important predictor for cataract surgery, the later accounting for a 2.38-fold increased risk for cataract surgery.
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Moro, Marcos Vinicius. "Estudos de técnicas de feixes iônicos para a quantificação do elemento químico boro." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-24092014-133916/.
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Neste trabalho, estudamos e aplicamos técnicas analíticas com feixes iônicos para a identificação e quantificação do elemento químico Boro em amostras de Boro depositado sobre Níquel 11B/Ni, sobre Silício B/Si e em amostras de Silício Grau Metalúrgico - SiGM. Estas últimas foram fornecidas pelo grupo de metalurgia do Instituto de Pesquisas Tecnológicas (IPT). Especificamente, as seguintes técnicas analíticas foram utilizadas: Nuclear Reaction Analysis - NRA, Elastic Recoil Detection Analysis - ERDA e Secondary Ion Mass Spectrometry - SIMS. Nas amostras de B/Ni e B/Si, as concentrações foram obtidas com medidas de NRA, ERDA e SIMS. Também foi abordado quais dentre essas três técnicas apresentam menor limite de deteção e menor incerteza para a quantificação de Boro. Usando a reação nuclear 11B(p,a0)8Be, foi possível calcular a sua seção de choque diferencial para ângulo de espalhamento theta=170, cujo resultado, para este ângulo específico, é inédito na literatura. As amostras de SiGM foram analisadas com a técnica SIMS e comparadas com medidas de Inductively Coupled Plasma - ICP realizadas pelo grupo do IPT. Uma vez que técnicas nucleares podem ser consideradas absolutas, concluímos que as medidas de ICP apresentaram dados compatíveis com as medidas SIMS, e que o grupo de metalurgia do IPT está medindo as concentrações de Boro em suas amostras de SiGM corretamente por meio de ICP. Uma reta de calibração entre medidas SIMSxICP foi construída, que poderá servir como um guia para futuras quantificações de Boro com ICP feitas pelo grupo de metalurgia do IPT.In this work we investigated the use of analytical techniques based on ion beams in the quantification of Boron in many kinds of samples. Specifically, we applied techniques such Nuclear Reaction Analysis (NRA), Elastic Recoil Detection Analysis (ERDA) and Secondary Ion Mass Spectrometry (SIMS) to 11B/Ni and B/Si samples to measure the boron concentration. We also discuss and show what technique has a better detection limit and lower uncertainty. For the first time in the literature, we obtained the cross section for the $^{11}B(p,\\alpha_0){^8}Be$ nuclear reaction in the energy range from 1.6 up to 2.0 MeV in theta = 170 scattering angle. The SIMS technique was applied to analise samples of metallurgical grade silicon (SiGM) from Metallurgy Group of Instituto de Pesquisas Tecnologicas (IPT) to check the Inductively Coupled Plasma (ICP) measurements carried out by the IPT. Moreover, it was possible to build a calibration curve between SIMS and ICP measurements, that can be used to help of Metallurgy Group with futures ICP\'s measurements.
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Hofmeister, Clara. "Development of Nitrogen Concentration During Cryomilling of Aluminum Composites." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5791.
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The ideal properties of a structural material are light weight with extensive strength and ductility. A composite with high strength and tailorable ductility was developed consisting of nanocrystalline AA5083, boron carbide and coarser grained AA5083. The microstructure was determined through optical microscopy and transmission electron microscopy. A technique was developed to determine the nitrogen concentration of an AA5083 composite from secondary ion mass spectrometry utilizing a nitrogen ion-implanted standard. Aluminum nitride and amorphous nitrogen-rich dispersoids were found in the nanocrystalline aluminum grain boundaries. Nitrogen concentration increased as a function of cryomilling time up to 72hours. A greater nitrogen concentration resulted in an enhanced thermal stability of the nanocrystalline aluminum phase and a resultant increase in hardness. The distribution of the nitrogen-rich dispersoids may be estimated considering their size and the concentration of nitrogen in the composite. Contributions to strength and ductility from the Orowan relation can be more accurately modeled with the quantified nitrogen concentration.M.S.M.S.E.
Masters
Materials Science Engineering
Engineering and Computer Science
Materials Science and Engineering; Accelerated BS to MS
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Marie, Yannick. "Étude de la formation des ions MCs+ en spectromètrie de masse d'ions secondaires : application à la quantification." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL124N.
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La spectrométrie de masse d'ions secondaires (SIMS) est une technique de microanalyse de surface très utilisée en raison de son excellente sensibilité (ppm-ppb), pour déterminer la présence de dopants et d'impuretés dans les matériaux. La quantification demeure son principal défaut à cause de l'importance de l'effet de matrice: la sensibilité d'un élément dépend fortement de la matrice dans laquelle il est analysé. Ce travail est consacré à l'étude d'une nouvelle technique, dite technique MCs+ ou cationisation, peu sensible à l'effet de matrice, permettant une analyse quantitative directe des matériaux complexes. Une étude détaillée des ions MCs+ montre que c'est leur mécanisme de formation par recombinaison qui est à l'origine de la faible sensibilité de la technique à l'effet de matrice. L’étude de plusieurs standards donne une première estimation de la fiabilité des résultats quantitatifs obtenus à l'aide de cette technique
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Pouech, Charlene. "Développement de méthodologies analytiques pour l'étude de la migration depuis des contenants en matière plastique prévus pour des applications pharmaceutiques vers des solutions aqueuses et des fluides biologiques." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10118.
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