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Tesi sul tema "Meteorites Analysis"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 28 gennaio 2023

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1

Malvin, Daniel Joshua 1959. "EXPERIMENTAL PARTITIONING OF SIDEROPHILE ELEMENTS IN THE SYSTEMS IRON - NICKEL - SULFUR - PHOSPHORUS AND FORSTERITE - ANORTHITE - DIOPSIDE." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276501.

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Partition coefficients in the Fe-Ni-S-P system measured utilizing "static" equilibration experiments cannot be reconciled with the results of "dynamic" experiments which mimic fractional crystallization. New tests of the "static" experiments demonstrate that they yield reliable equilibrium Ni, P and Ge partition coefficients. Partition coefficients in the Fe-Ni-S-P system are well matched by interpolation between the Fe-Ni-S and Fe-Ni-P subsystems. The crystal/liquid partitioning of Ga and Ge has been measured experimentally between forsterite, diopside, anorthite and spinel and melts in the forsterite-diopside-anorthite system. The coefficients for the exchange of Ga and Al and the exchange of Ge and Si between minerals and melts are within a factor of two of unity. Application of these results to the interpretation of natural basaltic samples demonstrates that Ga/Al and Ge/Si ratios can be used to discriminate between different mantle source regions.

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2

Shober, Patrick M. "Meteoroid Orbital Analysis: Connecting Meteorites and Asteroids." Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/86776.

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Since people started studying meteorites, scientists have attempted to better understand the parent bodies they originated from. Although, this is difficult because, unlike a terrestrial rock, you do not have access to the outcrop. The Near-Earth Object (NEO) population is the source of all meteorites found on Earth. Using the orbital data collected from the Desert Fireball Network, my work clarified the connections between meteorites and their source NEOs. I primarily did this analysis by employing rigorous numerical modeling techniques to constrain the dynamical and physical properties of asteroidal debris.

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3

Hontsova, S. S., and E. M. Maksimova. "X-Ray analysis of meteorite." Thesis, Sumy State University, 2014. http://essuir.sumdu.edu.ua/handle/123456789/39427.

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Meteorites are one of the most accessible objects of extraterrestrial matter. Therefore the study of the structural features and physical properties of crystals of meteorites can provide information about the formation of the crystal structure of matter in extraterrestrial conditions.

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4

Spitz, Anna Hargrave, and Anna Hargrave Spitz. "Trace element analysis of ureilite meteorites and implications for their petrogenesis." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185743.

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Ureilite meteorites are the second largest class of achondrite meteorites. They are perhaps the most enigmatic of all classes of meteorites and the dilemma over how they were formed has perplexed the meteoritic community for over a decade. This research was undertaken to illuminate the details of the petrogenesis of ureilites through the collection of trace element data. The results presented here indicate that many of the petrogenesis hypotheses promoted are no longer tenable and that the available data on ureilites are not sufficient to unravel the mystery of their origin. This dissertation discusses the data collected using two techniques: neutron activation analysis and inductively coupled plasma-mass spectrometry. Specific procedures required to study the ureilites (due to low concentrations of some trace elements) are delineated. Results are presented for the following elements: Ca, Co, Zn, Ga, Cu, Cs, Rb, Sr, Mo, Y, Ba, REE, Hf, W, Re and Ir. The results lead to the conclusion that the ureilites must be considered a mixture of materials--an original ultramafic rock formed by melting of processed source material combined with carbonaceous material added after the ultramafic formation. This conclusion explains the trace element chemical signatures and is supported by the age information obtained from Sm-Nd and Rb-Sr isotopic systems.

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5

Daly, Luke. "Understanding Our Protoplanetary Disk by Chemical Analysis of Components in Meteorites." Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/59045.

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This thesis has explored the capability of novel high resolution in situ analyses such as Synchrotron radiation, atom probe microscopy and transmission kikuchi diffraction in the analyses of primitive meteorites. Crystallographic, geochemical and isotopic data extracted using these techniques from refractory metal nuggets in primitive meteorites has implications for our understanding of how these grains formed, particle migration in the protoplanetary disk, and a suggestion that refractory metal nuggets may have a pre-solar origin.

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6

Armstrong, Katherine. "Chemical and Petrographic Survey of Large, Igneous-Textured Inclusions in Ordinary Chondrites." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/2070.

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Our inventory of material from the early solar system includes large, igneous-textured inclusions in O chondrites, whose origin and relationship to their host meteorite is unclear. These inclusions occur in approximately 4% of O chondrites, and are mineralogically, petrographically, and chemically diverse. Petrographic and chemical data from 29 inclusions from 23 host meteorites were collected with optical light and scanning electron microscopy, allowing for the determination of major phase modal abundance and major element bulk chemistry. No correlation between any inclusion property and host meteorite type were found, but some trends were observed. Nine of the inclusions show strong evidence, such as radial variations in texture and chemistry, for having crystallized as a free-floating droplet in a space environment, and may share the same formation process as chondrules. One inclusion is almost certainly shock-melted material that intruded into the host material. Thirteen inclusions have bulk chemistry patterns that suggest the material was vapor fractionated; the remaining sixteen are essentially chondritic, i.e., unfractionated. Broadly, the data support the conclusions of Ruzicka et al. (1998, 2000), which divided large inclusions into Na-poor (vapor fractionated) and Na-rich (unfractionated) groups, suggesting at least two different origins. There is no evidence that any of the inclusions studied formed by igneous differentiation.

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7

Schepker, Kristy Lee. "Complex Thermal Histories of L Melt Breccias NWA 5964 and NWA 6580." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1835.

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To constrain the thermal histories of two complex L chondrite melt breccia samples (NWA 5964 and NWA 6580) we compare textures and chemical compositions of metal and sulfide to L melt rock (NWA 6454 and NWA 6579) and strongly shocked (shock stage S6) (NWA 4860) samples. The inferred thermal histories can be used to evaluate formation settings on the L chondrite parent body. The L melt samples probably formed as different melt units within warm but largely unmelted material relatively close to the surface of the parent body, and the same is true for the S6 sample, except it experienced less melting. The breccia samples likely formed deeper, below different impact craters, by the injection of shock melt into a cooler chondritic basement. Carbide grains in the melt breccias could have formed by a contact metamorphic process caused by heating of the chondritic basement in proximity to the melt. Within the melt regions of the various samples, inferred cooling rates are on the order of 1-10 °C/sec, whereas in the chondritic portions of the melt breccias, the inferred cooling rates are many orders of magnitude slower, ~1-100 °C/My. The complex intergrowths of metal and FeS (hereafter referred to as dendritic grains) within the melt are recording cooling rates above the metal-sulfide eutectic, while the metal grains outside of the melt regions are recording cooling rates at much lower temperatures. It is likely the melt regions in the breccias cooled substantially prior to coming to rest against the chondritic basement, and thereafter the melt-chondrite rocks cooled more slowly.

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8

Maksimova, E. M., S. S. Hontsova, and I. A. Nauhatsky. "XRD Analysis of Crystal Structure of the Fragment of the Campo Del Cielo Meteorite." Thesis, Sumy State University, 2015. http://essuir.sumdu.edu.ua/handle/123456789/40668.

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Meteorites are the key, and often the only source of information about the pre-planetary and planetary early history of our solar system. Currently, the following classification of meteorites: stone (aerolites) stoney-iron (siderolites) and iron (siderites), depending on the ratio of silicate minerals in them, and nickel-iron.

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9

Hays, Naydene Richelle. "Geochronology of Shergottite Meteorites: Using LA-MC-ICP-MS Analysis to Examine U-Th-Pb Systematics of Baddeleyites and Phosphates." Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/202753.

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I present in-situ analysis of U-Pb systematics in baddeleyite and whitlockite grains from a suite of Martian shergottites. 9 baddeleyite grains (5 from basaltic shergottite NWA 2986 and 4 from olivine-phyric shergottite RBT 04262) were analyzed by LA-MC-ICP-MS. Despite low uranium and radiogenic lead concentrations , maximum ages could be determined for both samples: 187 ± 50 to 1236 ± 430 for NWA 2986 and 100 ± 9 to 526 ± 48 for RBT 04262. The same analytical procedures were used for whitlockites in NWA 2986, ALHA 77005, EETA 79001, NWA 2646 and LAR 06319. As with the baddeleyite analyses, maximum ages were calculated. These ages ranged from 110 ± 1 for LAR 06319 to 561 ± 185 for NWA 2646. These results, which are consistent with previous analyses, mean that the ~ 4 Ga age determined from Pb-Pb analyses cannot time the igneous crystallization of these meteorites.

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10

Joy, Katherine H. "Topics in lunar evolution using sample analysis and remotely sensed information." Thesis, University College London (University of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.606784.

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11

Bäckström, Ann. "Rock damage caused by underground excavation and meteorite impacts." Doctoral thesis, KTH, Teknisk geologi och geofysik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4824.

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The intent of this thesis is to contribute to the understanding of the origin of fractures in rock. The man-made fracturing from engineering activities in crystalline rock as well as the fracturing induced by the natural process of meteorite impacts is studied by means of various characterization methods. In contrast to engineering induced rock fracturing, where the goal usually is to minimize rock damage, meteorite impacts cause abundant fracturing in the surrounding bedrock. In a rock mass the interactions of fractures on the microscopic scale (mm-cm scale) influence fractures on the mesoscopic scale (dm-m scale) as well as the interaction of the mesocopic fractures influencing fractures on the macroscopic scale (m-km scale). Thus, among several methods used on different scales, two characterization tools have been developed further. This investigation ranges from the investigation of micro-fracturing in ultra-brittle rock on laboratory scale to the remote sensing of fractures in large scale structures, such as meteorite impacts. On the microscopic scale, the role of fractures pre-existing to the laboratory testing is observed to affect the development of new fractures. On the mesoscopic scale, the evaluation of the geometric information from 3D-laser scanning has been further developed for the characterisation of fractures from tunnelling and to evaluate the efficiency of the tunnel blasting technique in crystalline rock. By combining information on: i) the overbreak and underbreak; ii) the orientation and visibility of blasting drillholes and; iii) the natural and blasting fractures in three dimensions; a analysis of the rock mass can be made. This analysis of the rock mass is much deeper than usually obtained in rock engineering for site characterization in relation to the blasting technique can be obtained based on the new data acquisition. Finally, the estimation of fracturing in and around two meteorite impact structures has been used to reach a deeper understanding of the relation between fracture, their water content and the electric properties of the rock mass. A correlation between electric resistivity and fracture frequency in highly fractured crystalline rock has been developed and applied to potential impact crater structures. The results presented in this thesis enables more accurate modelling of rock fractures, both supporting rock engineering design and interpretation of meteorite impact phenomena.<br>QC 20100709

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12

Kloberdanz, Christine Marie. "Geochemical analysis of the Monturaqui Impact Crater, Chile." Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/835.

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13

White, Lee Francis. "Combined nanostructural and isotopic analysis of baddeleyite : new horizons in solar system chronology." Thesis, University of Portsmouth, 2017. https://researchportal.port.ac.uk/portal/en/theses/combined-nanostructural-and-isotopic-analysis-of-baddeleyite(80e4ee98-4090-4801-90f3-ce122bc9270a).html.

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Baddeleyite (monoclinic-ZrO2) is an exceptionally common accessory phase in many of the mafic and ultra-mafic rocks prevalent throughout the Solar System. This study presents the first ground-truthing efforts in the development of this robust mineral into a diagnostic indicator, discrete barometer, and precise U-Pb geochronometer of shock metamorphism by combining electron backscatter diffraction and atom probe tomography to generate unique chemical and structural datasets. Microstructural analysis of variably shocked baddeleyite grains around the Sudbury impact structure (Ontario, Canada) highlights a series of crystallographic structures that can be correlated with discrete variations in formative pressure-temperature conditions. Decompression at high temperatures generates a series of interlocking reversion twinned structures, while quenching forms a quasi-amorphous matrix. These features are comparable to those observed in extra-terrestrial samples, where they can be directly linked with the severity and extent of lead loss and age resetting. This finding facilitates the application of baddeleyite as a shock indicator, barometer (>5 GPa) and chronometer in a wide range of planetary materials. This structural variability is also observable on the nanometre scale. Analysis of the most highly shocked Sudbury baddeleyite using atom probe tomography reveals planar and curvi-planar fractures, trace element enriched subgrain boundaries, and solid-state diffusion clusters. These micrometre and nanometre scale features encourage localised diffusion of lead, with whole-microtip U-Pb analyses yielding complex partially reset ages. The application of atom probe tomography allows these features to be spatially resolved on the nanometre scale, yielding highly accurate ages for protolith crystallization and impact metamorphism within a single grain. These results have significant implications for the isotopic analysis of baddeleyite-bearing planetary materials, where the mechanisms of U-Pb age resetting have until now been poorly understood.

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14

Johnson, Reuben Carl. "Wetumpka impact structure modeled as the exposed remains of a large shallow water marine-target impact crater for analysis and interpretation of two drill cores taken from near the structure's geographic center." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Theses/JOHNSON_REUBEN_28.pdf.

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15

Huson, Sarah Ann. "Quantitative analysis of the deformational history and timing of the Sierra Madera impact structure, West Texas." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Dissertations/Spring2009/s_huson_043009.pdf.

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16

PEREIRA, JEAN MICHEL DA SILVA. "METEORITE ANALYSIS BY MASS SPECTROMETRY (252CF-PDMS) AND BY X-RAY AND INFRARED SPECTROSCOPIES (XRD, XRF, PIXE, FTIR AND RAMAN)." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=25645@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>A pesquisa em meteoritos é de extrema importância para o entendimento de certos processos astrofísicos, pois estes objetos trazem em sua estrutura informações fundamentais para a compreensão da evolução do Sistema Solar. Neste trabalho, são estudadas amostras dos meteoritos Isna, Allende e Zagami. As técnicas analíticas utilizadas foram: espectrometria de massa (252Cf-PDMS-TOF), espectroscopia vibracional (FTIR-MIR e Raman) e espectroscopias de raios X (XRF, XRD e PIXE). Além dessas análises, o meteorito Isna foi submetido a um processamento térmico com o objetivo de separar os constituintes refratários dos voláteis; as frações separadas foram analisadas por FTIR, Raman e PDMS. A composição elementar das amostras foi determinada por XRF e PIXE e comparadas. A informação dada pela técnica FTIR restringe-se praticamente à vibração da ligação Si-O. A técnica XRD fornece a composição mineralógica majoritária das fases cristalinas dos meteoritos Isna e Allende mostrando que ambos possuem olivina (forsterita - Mg2SiO4) e troilita (FeS). Os espectros Raman dos condritos carbonáceos Isna e Allende confirmam a ocorrência de olivina e revelam o grau de desordem da matéria orgânica contida em suas matrizes: o Allende tem maior grau de maturidade térmica, possivelmente por ter sido exposto a maiores temperaturas. O espectro Raman do não condrito Zagami mostra a existência de diopsídio (MgCaSi2O6). Os resultados obtidos por PDMS, para íons secundários positivos e negativos, permitem a identificação de isótopos e de estruturas silicáticas.<br>The research on meteorites is particularly relevant for the study of several astrophysics processes since these cosmic objects carry in their structure basic information useful for the understanding of the solar system evolution. In this work, samples of the Isna, Allende e Zagami meteorites are studied. The employed analytical techniques were: mass spectrometry (252Cf-PDMS-TOF), vibrational spectroscopy (FTIR-MIR and Raman) and X-ray spectroscopies (XRF, XRD and PIXE). In another series of measurements, the Isna meteorite was thermally processed aiming to separate the material into two samples: one, having residuals with refractory minerals, and another containing the sublimated and re-condensed constituents; the two fractions were analyzed by FTIR, Raman and PDMS. The elemental compositions of the samples were determined by XRF and PIXE. FTIR results are practically limited to the Si-O link absorption. The XRD analyses of Isna and Allende meteorites inform that the majoritarian mineralogical compositions of their crystalline phases are due to olivine (forsterite - Mg2SiO4) and to troilite (FeS). The Raman spectra the carbonaceous chondrites Isna and Allende confirm the occurrence of olivine and yields the disorder degree of the organic material in their matrixes: the Allende one has a higher thermal maturity degree, suggesting that it was exposed to higher temperatures in outer space. The Raman spectrum of the achondrite Zagami sample shows the occurrence of diopside (MgCaSi2O6). The PDMS results, obtained for positive and negative secondary ions, allow the identification of isotopes and of silicate structures.

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17

Minde, Peder. "Clast analysis of potential resurge deposits as part of the Vakkejokk Breccia in the Torneträsk area, northern Sweden - a proposed impact ejecta layer." Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-143782.

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In the northern part of Swedish Caledonides, north of Lake Torneträsk is a 7 km long exposure of a breccia layer. The layer thins westwards and eastwards from the central part where it is up to 27 m thick. It is called the Vakkejokk Breccia after the type section. The breccia has been described in literature since about a century, but its origin is enigmatic. The breccia layer is since the summer of 2012 investigated by three geologists specialized in impact craters, Paleozoic sediments, and the Caledonian orogeny. They put forward evidence for the breccia being formed by a hypervelocity impact during the Lower Cambrian at approximately 520 Ma (Ormö et al. 2017). At that time the target area was a shallow epicontinental sea that surrounded the mainly peneplanized continent Baltica. An impact into the sea is known to generate tsunami waves as well as resurge deposits when the water brings ejected and rip-up material back into the crater. Ormö et al. (2017) suggest the top part of the Vakkejokk Breccia to include such resurge deposits. The depositional marine environment is also known to rapidly protect an impact crater from further erosion. It is possible that only the topographic rim of the Vakkejokk crater was eroded during the millions of years it may have taken before the crater was covered by younger sediments. About 100 m.y. after the formation, it was completely covered by overthrust nappes during the Caledonian orogeny, when Baltica and Laurentia collided. The crater itself is not exposed today, merely parts of what is thought to be the ejecta layer and resurge deposits. This Bachelor of Science project aimed to investigate the putative resurge deposits to learn more about the process of formation and the provenance in the target of the clasts in the deposits. This was carried out by three short drillcores through the resurge deposit part of the Vakkejokk Breccia layer. The place to drill the boreholes was chosen at an outcrop which is proximal to the putative hidden crater. The retrieved drillcores were cut longitudinally, then polished and photographed in high resolution. Each core was then analyzed in an image analysis software with respect to clast granulometry and lithology. To the results are presented as graphs showing clast size, size sorting, clast shape, of the relative amounts of different lithologies and the matrix content. The results are discussed with respect to well-documented analogue marine-target craters

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18

Harper, Charles L. "On the nature of time in cosmological perspective : a comparative study of the weak and strong interaction chronometries via an analysis of high resolution ⁸⁷Rb-β-̄⁸⁷Sr, ²³⁵/²³⁸U-α-²⁰⁷/⁷⁰⁶Pb and ¹⁴²Sm-α-¹⁴³Nd isotopic age determinations of meteoritic, lunar and geological samples". Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670359.

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Noun, Manale. "Interaction agrégats-surface. Spectrométrie de masse par temps de vol et application analytique à des études sur des médicaments et sur la météorite Paris." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00906791.

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Le Lebanese Atomic Energy Commission (LAEC) poursuit un programme de développement des techniques analytiques pour compléter l'analyse par faisceau d'ions (IBA). Il a décidé de s'équiper d'un spectromètre de masse couplée à l'imagerie 2D puis récemment 3D avec l'acquisition d'un spectromètre de masse IONTOF V™ équipé de deux colonnes ioniques délivrant des faisceaux d'agrégats de bismuth et d'argon. Dans ce cadre, mon sujet de thèse a porté sur l'optimisation de l'instrument nouvellement acquis pour l'analyse d'échantillons contenant des composés organiques. Les premiers sujets de recherche sont la mise au point du protocole d'analyse quantitative de médicaments en utilisant la technique " cluster-SIMS-imaging " et l'analyse de la météorite Paris pour localiser la matière organique et déterminer sa composition. Dans les deux cas une approche multi-technique a été utilisée : IBA au LAEC, µ-Raman et µ-IR autour des équipements de Soleil et µPIXE réalisée auprès de l'accélérateur AGLAE (Centre de recherche et de restauration des musées de France, C2RMF).L'analyse de médicaments a été initiée au Liban en collaboration avec un fabricant local de produits pharmaceutiques (Mediphar Laboratories) dans le but d'établir de nouveaux procédés de contrôle qualité de produits finis. Mon étude a montré la complexité du dosage de médicament due à la présence de plusieurs molécules actives (Principe Actif, PA) et de substances organiques et minérales inactives (excipients) mélangées dans des conditions secrètes. Les effets de matrice sont dominants et modifient l'émission ionique conduisant à des erreurs systématiques importantes. Cette complexité a été analysée avec l'étude du Fludinium™ possédant deux PAs. Les résultats de cette étude ont permis d'obtenir la première courbe d'étalonnage du rapport des deux PAs et de quantifier ceux-ci dans les conditions du médicament commercial. Le protocole pour effectuer cette courbe d'étalonnage et les contrôles " qualité " ont été déterminés. Ceux-ci incorporeront une analyse en profil pour contrôler l'homogénéité des échantillons et l'obtention d'étalons produits par le fabricant en suivant ses processus de fabrication. En effet, les expériences ont montré que la réalisation du médicament en laboratoire à partir de ses éléments (PAs et excipients) ne donnait pas la même réponse ionique que le médicament commercial. L'analyse de la météorite Paris a été initiée par une collaboration avec une équipe de l'Institut d'Astrophysique Spatial d'Orsay impliquée dans l'exobiologie et la recherche des premières molécules pré-biotiques dans des échantillons extraterrestres. Le but des recherches est de caractériser la matière organique représentant quelques pourcents en poids dans une matrice minérale complexe, sans utiliser des méthodes chimiques pouvant induire une modification de ces molécules. Cette étude a démontré l'intérêt de l'approche multi-technique centrée autour de la spectrométrie de masse couplée à l'imagerie ionique pour déterminer les éléments principaux de la matrice minérale et organique. L'analyse par µPIXE avec une cartographie micrométrique a permis d'attribuer les distributions d'ions moléculaires et agrégats des spectres de masse aux différents composés minéraux. Ces attributions se poursuivent avec la constitution d'une base de données de spectres de référence. La composante organique a été extraite et les premières hypothèses de composition ont été envisagées autour des HAPs (Hydrocarbure Aromatique Polycyclique), MOI (Matière Organique Insoluble) et analogues de carbone amorphe produits par irradiation UV de glaces dont les compositions en gaz représentent différentes hypothèses pour les nuages interstellaires. Les protocoles d'analyses multi-techniques établis (incorporant un suivi de l'échantillon par spectrométrie de masse et imagerie ionique) permettent le démarrage d'analyse d'autres échantillons extra-terrestres collectés sur terre ou dans l'espace.

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Grant, Stephen Ian. "Medium frequency radar studies of meteors." 2003. http://thesis.library.adelaide.edu.au/public/adt-SUA20040224.152811.

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"July 2003." Includes bibliographical references (leaves 459-484) Electronic publication; full text available in PDF format; abstract in HTML format. Details the application of a medium frequency Doppler radar to observations of meteorites entering the Earth's atmosphere. Techniques were developed that verified system performance was to specification Electronic reproduction.[Australia] :Australian Digital Theses Program,2001. xx, 485 leaves : ill. ; 30 cm.

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Schilk, Alan J. "Chemical and statistical analyses of chondrules from the Mokoia (CV3) meteorite." Thesis, 1991. http://hdl.handle.net/1957/37445.

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Nearly 100 chondrules were extracted from -8.6g of the Mokoia (CV3) meteorite and have been analyzed by sequential instrumental neutron activation analysis (INAA). The resulting data were utilized in a comprehensive statistical characterization of these objects and, unlike similar investigations, virtually no loss of relevant data was incurred due to the use of inadequate or inappropriate software. Mass and elemental frequency distributions, correlation analysis and sorting coefficients support a "nebular" setting for chondrule genesis, and a scenario in which interstellar "dust-balls" (= chondrule precursors) are subject to some transient (short duration) high-energy process(es) followed by gravitationally or aerodynamically induced sorting, while it appears that an enhanced oxygen fugacity due to particle/gas fractionation may also be a factor. Conversely, a "planetary" setting for chondrule formation which requires the melting of pre-existing rocks (e.g., incompatible with the observed data. Factor analysis has led to the identification of the following precursor assemblages (i.e., factors) in the Mokoia chondrite: a refractory lithophile phase, a siderophile/chalcophile phase, a Mg-rich (silicate ?) phase, a refractory siderophile phase and a common lithophile phase. Previous studies of the Allende (CV3), Ornans (C03), Semarkona (LL3) and Chainpur (L3) meteorites are compared with these findings and interchondrite relationships are discussed (e.g., do these objects share similar parental materials, or are their compositions somehow complementary? were they formed in proximity with each other? etc.). A very unique oxide-sulfide-phosphate opaque assemblage was found in Mokoia and analyzed by INAA/electron-probe microanalysis, and may eventually serve to place constraints on the low-temperature thermal histories of chondrules or chondrites as well as provide information concerning the oxygen and sulfur fugacities within the Mokoia chondrite parent body.<br>Graduation date: 1991

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22

Milstein, Randall L. "The Calvin impact crater, Cass County, Michigan : identification and analysis of a subsurface ordovician astrobleme /." 1994. http://hdl.handle.net/1957/8989.

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23

Yin, Yu-Sheng, and 殷裕勝. "Characterization and Surface Analysis of the Antiques from Han Dynasty, Nan-Dan Iron Meteorite, and Microcapsules." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/95106199476818812787.

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24

Chen, Hsin-Wei, and 陳心維. "In situ Titanium Isotopic Composition Analysis of the Refractory Inclusions in the Allende Meteorite by Laser Ablation Inductive Couple Plasma Mass Spectrometry (LA-ICPMS)." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/19779048204037832903.

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25

Chen, Hsin-Wei. "In situ Titanium Isotopic Composition Analysis of the Refractory Inclusions in the Allende Meteorite by Laser Ablation Inductive Couple Plasma Mass Spectrometry (LA-ICPMS)." 2008. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2107200816415200.

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26

Meillieux, Damien Yves Justin. "Wellbore seismic and core sample measurement analysis integrated geophysical study of the Lake Bosumtwi impact structure /." Master's thesis, 2009. http://hdl.handle.net/10048/427.

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Thesis (M. Sc.)--University of Alberta, 2009.<br>Title from pdf file main screen (viewed on July 16, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Geophysics, Department of Physics, University of Alberta." Includes bibliographical references.

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