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Télédétection hyperspectrale : minéralogie et pétrologie, Application au volcan Syrtis Major (Mars) et à l'ophiolite d'OmanClenet, Harold 06 April 2009 (has links) (PDF)
Les roches mafiques à ultramafiques permettent de tracer les processus de formation et d'évolution des surfaces planétaires. Pour caractériser ces surfaces, la spectroscopie de réflectance visible-proche infrarouge est une technique adaptée de part sa sensibilité aux absorptions du fer présent dans les minéraux. L'objectif de cette thèse est de déterminer la composition modale des roches, ainsi que la composition chimique des minéraux constitutifs.<br />Nous avons développé une procédure basée sur la mise en oeuvre du Modèle Gaussien Modifié (MGM) qui permet de modéliser les spectres pour des assemblages minéralogiques complexes (olivine - orthopyroxène - clinopyroxène). Après validation de cette approche sur des données simples (poudres), la méthode a été appliquée à des roches naturelles complexes (météorites martiennes et roches d'Oman). Fort de l'expertise acquise dans cette étape intermédiaire, des cartographies minéralogiques ont alors pu être réalisées à partir de données spatiales et aéroportées, respectivement pour le volcan Syrtis Major sur Mars et le massif ophiolitique de Sumail (Oman). Nous avons ainsi montré que les laves de l'édifice volcanique présentent un enrichissement en olivine (Fo50-80) et que les pyroxènes, suivant les conditions de mise en place, peuvent avoir des compositions allant des augites aux enstatites. Pour l'ophiolite d'Oman, nous avons mis en évidence et cartographié pour la première fois des variations spatiales organisées de composition modale au sein même de l'unité harzburgitique. Nous avons également caractérisé des variations de composition dans les clinopyroxènes de la zone crustale ayant des implications pétrogénétiques.<br />Ces apports sont essentiels dans la caractérisation et la compréhension des processus pétrologiques inhérents à la formation des surfaces planétaires et devraient stimuler l'utilisation de l'imagerie spectroscopique à des fins géologiques.
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Observation depuis le sol des nuages et des poussières dans l'atmosphère. Applications à la stratosphère polaire et à l'atmosphère de MarsSarkissian, Alain 14 April 1992 (has links) (PDF)
Une méthode de détection des nuages et des poussières dans l'atmosphère depuis le sol par spectrométrie uv-visible du ciel au zénith est proposée. Elle repose sur l'étude de la variation de la couleur du ciel au crépuscule. La méthode est appliquée à la détection des nuages stratosphériques polaires observés durant la campagne Cheops III (Chemistry of ozone in the polar stratosphere) en 1990 en scandinavie. Un modèle de transfert radiatif en diffusion simple a été développé pour l'interprétation des observations. la méthode est ensuite appliquée à la définition d'un capteur optique destiné à la détection des tempêtes de poussière et de nuages dans l'atmosphère de Mars à partir de stations au sol, lors de la mission franco-russe Mars 94
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Electronic and Geometrical Structure of Phthalocyanines on Surfaces : An Electron Spectroscopy and Scanning Tunneling Microscopy StudyÅhlund, John January 2007 (has links)
Core- and Valence Photoelectron Spectroscopy (PES), X-ray- and Ultraviolet-Visible Absorption Spectroscopy (XAS and UV-Vis), Scanning Tunneling Microscopy (STM) and Density Functional Theory (DFT) calculations are used to study the electronic and geometrical structure of a class of macro-cyclic molecules, Phthalocyanines (Pc), on surfaces. These molecules are widely studied due to their application in many different fields. Multilayer and monolayer coverages of Iron Phthalocyanine (FePc) and metal-free Phthalocyanine (H2Pc) deposited on different surfaces are investigated in order to get insight in the electronic and geometrical structure of the obtained overlayers, of crucial importance for the understanding of the film functionality. Sublimation of molecular thick films on Si(100) and on conducting glass results in films with molecules mainly oriented with their molecular plane orthogonal to the surface. Ex-situ deposited H2Pc films on conductive glass show different molecular orientation and morphology with respect to the vacuum sublimated films. We study the monolayer adsorption structure of FePc and H2Pc and compare our results with other Pc’s adsorbed on graphite. We find that the molecular unit cell and the superstructure is characteristic for each Pc adsorbed on graphite, even if the geometrical size of the compared molecules is the same. The PE- and XA- spectra of FePc on graphite are essentially identical for the mono- and multilayer preparations, evidencing weak intermolecular and molecular-substrate interactions of van der Waals nature. Furthermore, we characterize Pc’s on InSb (001)-c(8x2). The substrate In rows are observed to be the adsorption site for Pc’s. We find that the growth of the two-dimensional islands of FePc is prolonged in the [-110] direction, in contrast to ZnPc adsorbed on the same substrate at room temperature. We interpret this result as an indication that the adsorption is controlled by the substrate corrugation observed at 70 K.
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A case study on building NPS into production lineLai, Yung-jin 30 July 2006 (has links)
The customer's taste is with the transition with constant time ¡A space¡A as the order pours into constantly¡A what an attitude the manufacturing plant is!¡A the flexible company quick in response turn into the existence ways of enterprises in the future¡A and under facing and producing state that must be expanded¡A how to set up production line and efficient duplicating the productive attitude fast fast¡A is it reach quantity produce quality that customer want fast ¡A must is it is it waste carry on procedure transformation to reduce to come through NPS (New Production Skill ) to come.
This research is mainly to visit the arrangement which refers to the theory of relevant documents to review and study through the executive inside the company¡A to understand the company understand the themes studied from the doing in the test amount factor of expanding the factory¡A set up NPS to be flat to take production line while being accurate ¡A utilize relevant step in accordance with follow ¡A make similar industry to establish NPS production line have one procedure way in accordance with following fast future.
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VECTORISATIONS ACTIVE ET PASSIVE DE RADIOPHARMACEUTIQUES DU TECHNETIUM-99m ET DU RHENIUM-188 POUR L'IMAGERIE MEDICALE ET LA THERAPIELepareur, Nicolas 28 November 2003 (has links) (PDF)
La recherche de nouvelles molécules pour la médecine nucléaire est un domaine en expansion croissante. Ces dernières années, le développement de nouveaux radiopharmaceutiques à visée thérapeutique a relancé l'intérêt pour la chimie du rhénium. En effet, les deux isotopes 186Re et 188Re, du fait de leurs propriétés adéquates et de leur analogie avec le 99mTc, largement utilisé pour les examens cliniques, semblent très prometteurs pour la préparation de radiopharmaceutiques.<br />Dans la première partie de ce manuscrit, la synthèse de complexes du rhénium et du technétium-99, [M(RPhCS3)2(RPhCS2)] (M = Re, Tc), est décrite. La préparation de radiopharmaceutiques à base de technétium-99m, analogues des composés obtenus à l'échelle pondérale, est également décrite. La stabilité/réactivité de ces complexes a été étudiée, au moyen de réactions d'échange avec d'autres ligands potentiels, et notamment par des dithiocarbamates, ainsi que par spectrophotométrie d'absorption UV-visible et analyse thermogravimétrique.<br />La réactivité des complexes vis-à-vis des dithiocarbamates conduit à la possibilité du greffage de biomolécules sur le cœur métallique, via le fragment dithiocarbamate. Cette méthode constitue une alternative potentielle aux procédures actuelles utilisant l'approche bifonctionnelle.<br /><br />Dans la seconde partie de ce manuscrit, la mise au point d'un kit pour le marquage du lipiodol par le rhénium-188 est décrite, à partir du complexe analogue des complexes décrits dans la première partie. L'huile radiomarquée ainsi obtenue est potentiellement utilisable pour le traitement de l'hépatocarcinome. La stabilité in vitro et in vivo du complexe rhénié 188Re-SSS lipiodol et de son analogue technétié 99mTc-SSS lipiodol a été étudiée, ainsi que leur comportement in vivo sur un modèle de porc sain.<br />Cette étude a permis de montrer la fixation quasi-exclusive du radiopharmaceutique au niveau du foie, ainsi que la stabilité de ce composé. Sa sélectivité pour les tumeurs reste à démontrer avant de passer aux premiers essais chez l'homme.
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Corrosion Protection Performance and Spectroscopic Investigations of Soluble Conducting Polyaniline-Dodecylbenzenesulfonate Synthesized via Inverse Emulsion ProcedureShreepathi, Subrahmanya, Hoang, Hung Van, Holze, Rudolf 09 May 2009 (has links) (PDF)
Corrosion protection performance of a completely soluble polyaniline-dodecylbenzenesulfonic acid salt (PANI-DBSA) on C45 steel has been studied with electrochemical impedance and potentiodynamic measurements. Chloroform is the most suitable solvent to process the pristine PANI-DBSA because of negligible interaction of the solvent with the polyaniline (PANI) backbone. An anodic shift in the corrosion potential (<img src="http://scitation.aip.org/stockgif3/Dgr.gif" alt="Delta" align="bottom" border="0"><i>E</i>=~70 mV), a decrease in the corrosion current and a significant increase in the charge transfer resistance indicate a significant anti-corrosion performance of the soluble PANI deposited on the protected steel surface. Corrosion protection follows the mechanism of formation of a passive oxide layer on the surface of C45 steel. In situ UV-Vis spectroscopy was used to investigate the differences in permeability of aqueous anions into PANI-DBSA. Preliminary results of electron diffraction studies show that PANI-DBSA possesses an orthorhombic type of crystal structure. An increase in the feed ratio of DBSA to aniline increases the tendency of aggregation of spherical particles of PANI obvious in transmission electron microscopy. PANI-DBSA slowly loses its electrochemical activity in acid free electrolyte without undergoing degradation.
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"People Like Me": Racialized Teachers and the Call for CommunityHopson, Robin Liu 09 January 2014 (has links)
The city of Toronto is one of most racially diverse places in the world, with almost half of its population identifying as being a “visible minority” (Statistics Canada, 2010). As a result, the field of education faces the question of how to meet the needs of their transforming student demographics. Numerous researchers and institutional policies have responded to these changes by endorsing the hiring of a teaching staff that is reflective of the racially diversifying student population (Ontario Ministry of Education, 2009; Ryan, Pollock, & Antonelli, 2009; Solomon, & Levine-Rasky, 2003). The assumption, however, that racialized educators will automatically be effective teachers or role models for racialized students homogenizes their social differences and reduces the multiplicity of their identities to the colour of their skin (Martino, & Rezai-Rashti, 2012). What is urgently lacking from these dominant discourses are the voices of racialized individuals, whose inside perspectives and lived experiences can provide valuable insights about the roles of equity and race in education.
Using an anti-racist theoretical framework to guide my research methodology, this study examines how racialized teachers understand their classroom practices, school relationships, and institutional policies with respect to race, equity, and the expectations that are cast to them as “visible minority” educators. A document analysis of educational statements that discuss race, equity, and anti-racism reveals that while policy has progressed, the presentation of these issues remains largely superficial and does not provide enough information or transparency to adequately communicate their importance. Nevertheless, the power of these dominant discourses has been vastly significant in shaping the lived experiences and feelings of racialized teachers, 21 of whom were individually interviewed using a qualitative, semi-structured method.
The inside perspectives of these teachers demonstrate the complexity of race and its inadvertent impact on their roles as educators; their feelings and reactions illustrate the ongoing gap between policy and practice, the ignorance that is embedded in notions of racial matching between teachers-students, and the persevering call for a professional community where individual differences are viewed as opportunities to learn rather than obstacles that need to be overcome.
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シーケンシに基づく通信方式の可視光通信への応用山里, 敬也 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(C)(2) 課題番号:16560330 研究代表者:山里 敬也 研究期間:2004-2005年度
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"People Like Me": Racialized Teachers and the Call for CommunityHopson, Robin Liu 09 January 2014 (has links)
The city of Toronto is one of most racially diverse places in the world, with almost half of its population identifying as being a “visible minority” (Statistics Canada, 2010). As a result, the field of education faces the question of how to meet the needs of their transforming student demographics. Numerous researchers and institutional policies have responded to these changes by endorsing the hiring of a teaching staff that is reflective of the racially diversifying student population (Ontario Ministry of Education, 2009; Ryan, Pollock, & Antonelli, 2009; Solomon, & Levine-Rasky, 2003). The assumption, however, that racialized educators will automatically be effective teachers or role models for racialized students homogenizes their social differences and reduces the multiplicity of their identities to the colour of their skin (Martino, & Rezai-Rashti, 2012). What is urgently lacking from these dominant discourses are the voices of racialized individuals, whose inside perspectives and lived experiences can provide valuable insights about the roles of equity and race in education.
Using an anti-racist theoretical framework to guide my research methodology, this study examines how racialized teachers understand their classroom practices, school relationships, and institutional policies with respect to race, equity, and the expectations that are cast to them as “visible minority” educators. A document analysis of educational statements that discuss race, equity, and anti-racism reveals that while policy has progressed, the presentation of these issues remains largely superficial and does not provide enough information or transparency to adequately communicate their importance. Nevertheless, the power of these dominant discourses has been vastly significant in shaping the lived experiences and feelings of racialized teachers, 21 of whom were individually interviewed using a qualitative, semi-structured method.
The inside perspectives of these teachers demonstrate the complexity of race and its inadvertent impact on their roles as educators; their feelings and reactions illustrate the ongoing gap between policy and practice, the ignorance that is embedded in notions of racial matching between teachers-students, and the persevering call for a professional community where individual differences are viewed as opportunities to learn rather than obstacles that need to be overcome.
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Explorations of Functionalized Gold Nanoparticle Surface Chemistry for Laser Desorption Ionization Mass Spectrometry ApplicationsGomez Hernandez, Mario 1980- 02 October 2013 (has links)
Functionalized nanoparticles provide a wide range of potential applications for Biological Mass Spectrometry (MS). Particularly, we have studied the effects of chromophore activity on the performance of gold nanoparticles (AuNPs) capped with substituted azo (-N=N-) dyes for analyte ion production in Laser Desorption Ionization Mass Spectrometry (LDI-MS) conditions. A series of aromatic thiol compounds were used as Self-Assembled Monolayers (SAM) to functionalize the surface of the AuNPs. Results indicate that AuNPs functionalized with molecules having an active azo chromophore provide enhanced analyte ion yields than the nanoparticles capped with the hydrazino analogs or simple substituted aromatic thiols.
We have also conducted experiments using the azo SAM molecules on 2, 5, 20, 30, and 50 nm AuNPs exploring the changes of Relative Ion Yield (RIY) with increased AuNP diameters. Our results indicate that the role of the SAM to drive energy deposition decreases as the size of the AuNP increases. It was determined that 5 nm is the optimum size to exploit the benefits of the SAM on the ionization and selectivity of the AuNPs.
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