Thèses : « TEM ANALYSIS »

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Foo, Seng-Lee. « Analysis of electromagnetic fields in loaded TEM cells ». Thesis, University of Ottawa (Canada), 1988. http://hdl.handle.net/10393/5170.

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Kylberg, Gustaf. « Automatic Virus Identification using TEM : Image Segmentation and Texture Analysis ». Doctoral thesis, Uppsala universitet, Avdelningen för visuell information och interaktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217328.

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Viruses and their morphology have been detected and studied with electron microscopy (EM) since the end of the 1930s. The technique has been vital for the discovery of new viruses and in establishing the virus taxonomy. Today, electron microscopy is an important technique in clinical diagnostics. It both serves as a routine diagnostic technique as well as an essential tool for detecting infectious agents in new and unusual disease outbreaks. The technique does not depend on virus specific targets and can therefore detect any virus present in the sample. New or reemerging viruses can be detected in EM images while being unrecognizable by molecular methods. One problem with diagnostic EM is its high dependency on experts performing the analysis. Another problematic circumstance is that the EM facilities capable of handling the most dangerous pathogens are few, and decreasing in number. This thesis addresses these shortcomings with diagnostic EM by proposing image analysis methods mimicking the actions of an expert operating the microscope. The methods cover strategies for automatic image acquisition, segmentation of possible virus particles, as well as methods for extracting characteristic properties from the particles enabling virus identification. One discriminative property of viruses is their surface morphology or texture in the EM images. Describing texture in digital images is an important part of this thesis. Viruses show up in an arbitrary orientation in the TEM images, making rotation invariant texture description important. Rotation invariance and noise robustness are evaluated for several texture descriptors in the thesis. Three new texture datasets are introduced to facilitate these evaluations. Invariant features and generalization performance in texture recognition are also addressed in a more general context. The work presented in this thesis has been part of the project Panvirshield, aiming for an automatic diagnostic system for viral pathogens using EM. The work is also part of the miniTEM project where a new desktop low-voltage electron microscope is developed with the aspiration to become an easy to use system reaching high levels of automation for clinical tissue sections, viruses and other nano-sized particles.

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Hajduček, Jan. « Zobrazování metamagnetických tenkých vrstev pomocí TEM ». Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443233.

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Komplexní magnetické materiály v nanoměřítku mají své nezastupitelné místo v moderních zařízeních, jako jsou digitální paměti nebo senzory. Moderní technologické procesy vyžadují porozumění a možnost kontroly moderních magnetických materiálů až na atomární úrovni. Jednou z možných cest je magnetická analýza za použití transmisní elektronové mikroskopie (TEM), která je unikátní díky možnosti zobrazování až v subatomárním měřítku. Tato práce popisuje možnosti zobrazování metamagnetických materiálů metodou TEM. Tyto materiály se vyznačují možností stabilizace více magnetických uspořádání najednou za daných vnějších podmínek. Modelovým systémem pro popis zobrazovacích možností metody TEM byly zvoleny tenké vrstvy metamagnetické slitiny FeRh. Tento materiál prochází při zahřívání fázovou přeměnou z antiferomagnetické do feromagnetické fáze. Podrobně jsou rozebrány procesy výroby vzorků, což je zásadní pro úspěšnou TEM analýzu. Pro magnetické zobrazování vzorků v TEMu je využita technika diferenciálního fázového kontrastu (DPC), umožňující přímé mapování rozložení magnetické indukce ve vzorku. Důsledně je diskutován vznik signálu v DPC, což je nezbytné pro porozumění a analýzu výsledných dat. FeRh vrstvy jsou podrobeny analýze struktury, chemického složení a především magnetických vlastností obou magnetických fází. Závěrem je představen proces přímého ohřevu metamagnetických vrstev v TEMu.

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Nord, Magnus Kristofer. « Quantitative (S)TEM analysis of intermediate band solar cell materials ». Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13655.

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In this thesis the strain properties of two InAs/GaAs quantum dot intermediate band solar cell materials have been explored. Both samples were thin films grown on a (100) GaAs substrate. The quantum dot material was InAs, and the bulk material was GaAs. One sample had AlAs-cap, while the other had GaAs-cap. Geometrical phase analysis was used to study the strain. A higher degree of strain was found in the AlAs-capped sample. Negative strain was observed in directly above and below the quantum dots in both samples. A stacking fault in a quantum dot in the AlAs-capped sample was found to relax all the strain. Analysis of the chemical composition of the AlAs-capped sample was performed using HAADF-STEM and multislice analysis. This analysis found an average indium concentration inside the quantum dots of 25% +- 10%, with peaks up to 50%.

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ElFallagh, Fathi Ali. « 3D Analysis of Indentation Damage by FIB tomography and TEM ». Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500111.

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McLaughlin, Kirsten Kathleen. « TEM diffraction analysis of the deformation underneath low load indentations ». Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613392.

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Sears, Jasmine, Ricky Gibson, Michael Gehl, Sander Zandbergen, Patrick Keiffer, Nima Nader, Joshua Hendrickson, Alexandre Arnoult et Galina Khitrova. « TEM EDS analysis of epitaxially-grown self-assembled indium islands ». AMER INST PHYSICS, 2017. http://hdl.handle.net/10150/624718.

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Epitaxially-grown self-assembled indium nanostructures, or islands, show promise as nanoantennas. The elemental composition and internal structure of indium islands grown on gallium arsenide are explored using Transmission Electron Microscopy (TEM) Energy Dispersive Spectroscopy (EDS). Several sizes of islands are examined, with larger islands exhibiting high (>94%) average indium purity and smaller islands containing inhomogeneous gallium and arsenic contamination. These results enable more accurate predictions of indium nanoantenna behavior as a function of growth parameters. (C) 2017 Author(s).

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Issa, Inas. « In situ TEM nanocompression and mechanical analysis of ceramic nanoparticles ». Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI008/document.

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Dans cette étude, nous proposons d’utiliser la compression in situ dans le MET afin de caractériser les propriétés mécaniques de nanoparticules céramiques dont la taille caractéristique est de l’ordre de quelques dizaines de nanomètres. Nous appliquerons cette méthode à des nanocubes monocristallins de MgO, une céramique modèle dont la plasticité est bien connue dans le matériau massif. Les essais de nanocompression montrent que les nanocubes de MgO se déforment de façon homogène jusqu’à de grandes déformations (>50%) sans fissure apparente. L’analyse des résultats est assistée par des méthodes de corrélation d’images numériques et simulations de type dynamique moléculaire. Le mécanisme de déformation et l'effet de taille sur la limite élastique sont identifiés. Dans une deuxième partie de la thèse, nous présentons une étude sur des nanoparticules d’alumine de transition compactée en CED (Cellule à Enclumes en Diamant) à température ambiante, sous plusieurs pressions (5 GPa, 15 GPa et 20 GPa). Des lames minces préparées par FIB ont été étudiées en MET. Des images HRTEM montrent une texture cristallographique qui devient plus importante à des pressions plus élevées. Une orientation cristallographique préférentielle est observée, avec les plans {220} de la phase gamma de l’alumine la plupart du temps parallèles à la surface de contact avec une particule voisine. Ce comportement mécanique est cohérent avec un système de glissement, connu pour les structures spinelles. Une corrélation de ce comportement avec les tests in situ MET réalisés sur des nanoparticules similaires, par Emilie Calvié lors de sa thèse, est présentée. Enfin, des clichés de diffraction de type Debye Scherrer sont réalisés sur ces lames minces de nanoparticules d’alumine de transition compactées en CED à différentes pressions. L’analyse quantitative de ces clichés montre une transformation de phase de ces nanoparticules d’alumine de phase gamma en phase delta, de manière croissante avec la pression
In this study, we propose an innovative mechanical observation protocol of ceramics nanoparticles in the 100nm size range. This Protocol consists of in situ TEM nanocompression tests of isolated nanoparticles. Load–real displacements curves, obtained by Digital Image Correlation, are analyzed and these analyses are correlated with Molecular Dynamics simulations. By this protocol a constitutive law with its mechanical parameters (Young modulus, Yield stress...) of the studied material at the nano-scale can be obtained. In situ TEM nano-compression tests on magnesium oxide nanocubes are performed. Magnesium oxide is a model material and its plasticity is very well known at bulk. The MgO nanocubes show large plastic deformation, more than 50% of plastic strain without any fracture. The TEM results are correlated to MD simulations and the deformation mechanism can be identified.The size effect and the electron beam effect on the yield strength are investigated. In a second part of the dissertation, we present a study on transition alumina nanoparticles compacted in a Diamond Anvil Cell at different uniaxial pressures. Thin Foils of these compacted nanoparticles are prepared by FIB for HRTEM Observations. Their analysis reveals the plastic deformation of the nanoparticles. The crystallographic texture observed inthese compacted nanoparticles in DAC shows a preferred orientation of the {110} lattice planes, orientated perpendicular to the compression direction. This is compatible with the slip system. This argument was reinforced with a preferred orientation of slip bands observed during in situ TEM nano-compression tests. Moreover, electron diffraction patterns (Debye Scherrer) analysis on these compacted transition alumina nanoparticles reveals the decrease of the presence of gamma-alumina and the increase of delta-alumina with increasing pressure. This reveals the phase transformation with increasing pressure from gamma to delta* alumina

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King, Jason Peters King. « An investigation of spin-valves and related films by TEM ». Thesis, University of Glasgow, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301949.

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Woonbumroong, Apinya. « Fresnel contrast analysis and analytical TEM study of grain boundaries in electroceramics ». Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624490.

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Cikánek, Martin. « Detekce biologických struktur ve snímcích z TEM mikroskopu ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400528.

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The aim of the first part of this thesis is to explain the theoretical basis of transmission electron microscopy and to mention fundamental parts of transmission electron microscopes. The next part of this work is focused on possible methods of image segmentation, the use of neural networks in the detection of objects in an image and the subsequent clustering of results. The theoretical part of the thesis is concluded with an explanation of some already published methods of automatic detection of biological structures in microscopic images and theoretical design of the algorithm, which will be subsequently developed. The process of training neural networks in order to automatically detect biological structures in an image is described at the beginning of the practical part. This is followed by an evaluation of the results achieved by these networks. Subsequently, cluster analysis methods are applied to these results, the products of which are compared with each other and also with the results obtained by already published methods.

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Moore, David Anton. « Processing and analysis of seismic reflection and transient electromagnetic data for kimberlite exploration in the Mackenzie Valley, NT ». Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/5027.

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The Lena West property near Lac des Bois, NT, held by Diamondex Resources Ltd., is an area of interest for exploration for kimberlitic features. In 2005, Frontier Geosciences Inc. was contracted to carry out seismic reflection and time-domain transient electromagnetic (TEM) surveys to investigate the possibility of kimberlite pipes being the cause of total magnetic intensity (TMI) anomalies previously identified on the property. One small part of the property, Area 1915, was surveyed with two perpendicular seismic reflection lines 1550 m and 1790 m long and three TEM lines consisting of six or seven individual soundings each with a 200 m transmitter loop. The results generated by Frontier Geosciences did not indicate any obvious vertical features that correlated with the TMI anomaly. The purpose of this study is to reprocess the seismic reflection data using different approaches than those of Frontier Geosciences and to invert the TEM data using a 1-D inversion code, EM1DTM recently developed by the UBC Geophysical Inversion Facility, to improve upon previous results and enhance the interpretation. A secondary objective is to test the robustness of EM1DTM when applied to observed TEM data, since prior to this study it had only been applied to synthetic data. Selective bandpass filtering, refraction and residual statics and f-x deconvolution procedures contributed to improved seismic images to the recorded two-way traveltime of 511.5 ms (approximately 1100 m depth). The TEM data were successfully inverted and converted to pseudo 2-D recovered resistivity sections that showed similar results to those from Frontier Geosciences. On the final seismic reflection sections, several strong reflectors are identified and the base of the overlying sedimentary layers is interpreted at a depth of ~600 m. The TEM results show consistent vertical structure with minimum horizontal variation across all lines to a valid depth of ~150 m. However, neither TEM nor seismic reflection results provide any information that correlates well with the observed TMI anomaly.

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Daykin, Adam C. « A TEM analysis of the Co//Si(111) system using bicrystallographic symmetry theory ». Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316591.

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Liu, Jing. « Implementation of a Semi-automatic Tool for Analysis of TEM Images of Kidney Samples ». Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-180813.

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Glomerular disease is a cause for chronic kidney disease and it damages the function of the kidneys. One symptom of glomerular disease is proteinuria, which means that large amounts of protein are emerged in the urine. To be more objective,transmission electron microscopy (TEM) imaging of tissue biopsies of kidney are used when measuring proteinuria. Foot process effacement (FPE), which is defined as less than1 ”slit”(gap)/micrometer at the glomerular basement membrane (GBM). Measuring FPE is one way to detect proteinuria using kidney TEM images, this technique is a time-consuming task and used to be measured manually by an expert. This master thesis project aims at developing a semi-automatic way to detect the FPE patients as well as a graphic user interface (GUI) to make the methods and results easily accessible for the user. To compute the slits/micrometer for each image, the GBM needs to be segmented from the background. The proposed work flow combines various filters and mathematical morphology to obtain the outer contour of the GBM. The outer contour is then smoothed, and unwanted parts are removed based on distance information and angle differences between points on the contour. The length is then computed by weighted chain code counts. At last, an iterative algorithm is used to locate the positions of the "slits" using both gradient and binary information of the original images. If necessary, the result from length measurement and "slits" counting can be manually corrected by the user. A tool for manual measurement is also provided as an option. In this case, the user can add anchor points on the outer contour of the GBM and then the length is automatically measured and "slit" locations are detected. For very difficult images, the users can also mark all "slits" locations by hand. To evaluate the performance and the accuracy, data from five patients are tested,for each patient six images are available. The images are 2048 by 2048 gray-scale indexed 8 bit images and the scale is 0.008 micrometer/pixel. The one FPE patient in the dataset is successfully distinguished.

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Olander, Petra. « Quantitative Analysis of TiWCN in Cemented Carbide : A Comparison of Spectroscopic Techniques ». Thesis, Uppsala universitet, Institutionen för materialkemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-143490.

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The aim of this master thesis was to compare EELS in TEM with TEM-EDS and WDS-EPMA for quantitative analysis of γ-phase in cemented carbide. Especially, the quantification of the light elements nitrogen and carbon in compounds like TiCxN1-x is interesting, since this is problematic. The techniques were compared by acquiring spectra for quantification of two samples of cemented carbide containing γ-phase (Tix,W1-x)(CyN1-y) with different nitrogen and tungsten content. Also, a rigorous evaluation about how EELS spectra best is acquired and processed was performed in order to enable the comparison. Experimental results show that EELS gives satisfying results for TiC0.7N0.3 and that EELS is comparable with WDS-EPMA for quantification of nitrogen, carbon and titanium in (Tix,W1-x)(CyN1-y) when the atomic concentration of nitrogen is around 20%. However, EELS was not used for quantification of tungsten. Concluded is also that EELS and WDS should be considered as complementary rather than competing techniques.

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Vilela-Ardenghi, Ana Carolina Nunes da Cunha 1981. « "Minha terra tem palmeiras..." : aspectos discursivos da construção de um espaço "tipicamente" brasileiro ». [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/268911.

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Orientador: Sírio Possenti
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem
Made available in DSpace on 2018-08-25T01:44:00Z (GMT). No. of bitstreams: 1 Vilela-Ardenghi_AnaCarolinaNunesdaCunha_D.pdf: 4116045 bytes, checksum: 91005fd1da4528800d994be24c8a0652 (MD5) Previous issue date: 2014
Resumo: A partir do modo de circulação da cristalização do que chamamos aqui de espaço nacional, este trabalho debruçou-se sobre o estudo dos estereótipos, assumidos não como algo "engessante" ou redutor, mas como uma regularização, efeito de retomadas, paráfrases e repetições que levam ao "esquecimento" da origem enunciativa. Entendemos o espaço nacional como uma paisagem "típica" associada a um país, ou, em outros termos, aquilo que é tomado como sendo a melhor representação do espaço físico desse país. No caso brasileiro, historicamente, a imagem construída é a do próprio "paraíso terreal" e ela tem particular importância na medida em que, como aponta Chauí (2006), funciona como um "mito fundador", uma narrativa que não cessa de ser retomada e que impõe um vínculo interno com um passado de origem que, paradoxalmente, nunca cessa de existir, mantendo-se sempre perene. O corpus reunido para esta pesquisa ¿ proveniente do turismo e da moda ¿ atesta essa perenidade. Para analisá-lo, mobilizamos, de início, o conceito de pré-construído que, conforme sugerem Amossy & Pierrot (2005), é um aporte teórico importante ¿ e talvez insuficientemente explorado ¿ para o estudo dos estereótipos do interior do quadro teórico-metodológico da Análise do Discurso (AD). Embora tenha, de fato, mostrado ser um conceito relevante para a apreensão do modo de funcionamento dos estereótipos, os dados provam também que não pode haver uma relação direta ¿ ou exclusiva ¿ entre estereótipos e pré-construídos. Para além destes, os estereótipos relacionam-se, como mostram as análises do corpus, a simulacros e cenas validadas (Maingueneau, 2002). Do ponto de vista metodológico, a apreensão do corpus reunido suscitou um conjunto de reflexões em torno da proposta de Maingueneau (2006) para a noção de formação discursiva enquanto uma unidade não tópica de análise
Abstract: From the circulation mode of crystallization of what we here call a national space, this work focused on the study of stereotypes, undertaken not as something "limiting" or as a reducer, but as a regularization, due to retakes, paraphrases and repetitions that lead to "oblivion" of the original enunciation. We understand the national space as a "typical" landscape associated with a country, or, in other terms, that which is taken as being the best representation of the physical space of this country. In the Brazilian case, historically, the image is built from the "earthly paradise" and it is of particular importance to the extent that, as observed by Chauí (2006), works as a "founding myth", a narrative that does not cease to be retaken and imposing an internal link with a past of origin which, paradoxically, never ceases to exist, remaining perennial. The corpus assembled for this study ¿ from tourism and fashion ¿ testifies this perpetuity. To analyze it, we mobilized, at first, the concept of pre-construed, that, as suggested by Amossy & Pierrot (2005), is an important theoretical contribution ¿ and perhaps insufficiently explored ¿ for the study of stereotypes within the theoretical methodological framework of Discourse Analysis (DA). Although, in fact, shown to be a relevant concept for the apprehension of the mode of operation of the stereotypes, the data prove also that there cannot be a direct ¿ or exclusive ¿ relationship between stereotypes and the pre-construed. In addition to these, stereotypes relate, as shown by the analysis of the corpus, the simulacra and validated scenes (Maingueneau, 2002). From the methodological point of view, the gathering of the corpus brought about a set of reflections around the proposition of Maingueneau (2006) for the notion of the discursive formation as a non topic analysis unit
Doutorado
Linguistica
Doutora em Linguística

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Jenei, István Zoltán. « Nanoparticle assisted tribofilm formation and material transfer studied with SEM and TEM ». Doctoral thesis, Stockholms universitet, Fysikum, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-114745.

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The discovery and subsequent synthesis of metal containing fullerenes- IFS (Inorganic Fullerene-like Structures) by R. Tenne et al. has generated considerable scientific interest with great potential impact in many industrial application areas such as lubrication. The lubrication mechanism (tribofilm formation) via exfoliation and deposition of the atomic layers from this cage-like IF-particles was revealed and demonstrated first by this research group. The incorporation of the nanoparticles into lubricants (oils, greases) is however not straightforward. When two surfaces are sliding against each other and a lubricant is used, a thin layer (tribofilm) is formed on the contact area. The friction reducing effects of the nanoparticles can be altered or hindered by certain additives that are used in lubricative oils. The effects of such additives on the tribological behavior of the nanoparticles are investigated by analyzing the tribofilms formed on the worn surfaces using energy-dispersive X-ray spectroscopy in a scanning electron microscope. Another challenge of nanoparticles in lubricants is the penetration of the nanoparticles into the contact zone. A possible solution of this problem is briefly discussed. A modified burnishing technique can be used to coat sliding metallic surfaces with a friction reducing tribofilm. The morphology and composition of these tribofilms was investigated with analytical electron microscopy techniques. In the second part of the thesis electron microscopy was used to investigate the material transfer. Titanium is an elements with high adhesive ability to the counter surface, it displays poor tribological properties in sliding metallic contacts. This can lead to material transfer and consequently severe surface damage. The cold formation and machining of titanium, thus can lead rapid tool wear and poor surface finish. Electron microscopy techniques were used to study the mechanism of titanium transfer to different counter surfaces.

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Xiang, Maiqi. « Aerosol sampling and characterization technique using TEM porous grids ». Thesis, Compiègne, 2021. http://www.theses.fr/2021COMP2611.

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La caractérisation et l’analyse des particules nano/micromètriques solides en suspension dans l’air ont récemment reçu une attention considérable. Le prélèvement représentatif des particules à analyser est une exigence fondamentale. L’échantillonneur d’aérosols récemment développé appelé Mini Particle Sampler (MPS), qui est équipé d’une grille poreuse de Transmission Electron Microscopy (TEM), rend l’échantillonnage de particules possible. Cependant, l’exploitation des résultats de ce système d’échantillonnage est encore à l’étape précoce. Cette thèse améliore et quantifie le système d’échantillonnage MPS. En outre, une nouvelle méthode de caractérisation de la masse de polluants est développée sur la base du système d’échantillonnage optimisé. L’efficacité d’échantillonnage des particules dont le diamètre de mobilité varie de 5à 100 nm est principalement étudiée. Selon l’analyse de sensibilité des paramètres dans l’ensemble de la configuration effectuée par la méthode Taguchi, la concentration en sel de l’atomiseur, la polarité à haute tension dans Differential Mobility Analyzer (DMA), la méthode d’évaluation de l’efficacité d’échantillonnage, la température d’échantillonnage, et la porosité de la grille TEM affectent le moins possible l’efficacité de collection. L apetite taille des pores du filtre, le débit élevé et les particules plus denses augmentent l’efficacité de collection des particules, qui sont les principaux paramètres. Basé sur l’étude des mécanismes de filtration des grilles TEM et la comparaison des modèles théoriques disponibles, une méthode d’analyse expérimentale de l’efficacité de collection combinée à la modélisation théorique est développée en considérant l’applicabilité du modèle. En utilisant cette méthode, les effets des principaux paramètres mentionnés ci-dessus sont comparés entre les expériences et les théories. La technologie d’échantillonnage est optimisée et l’efficacité minimale de collecte peut atteindre 40% en ajustant les paramètres du système d’échantillonnage. De plus, selon les méthodes de Monte-Carlo, les incertitudes sur l’efficacité de collection à partir des données mesurées et des modèles sont généralement inférieures à 1% et à 9%, respectivement. La plupart des données d’efficacité de collection mesurées sont couvertes par la plage d’incertitude d’efficience simulée par les modèles. L’analyse de sensibilité basée sur la variance de Sobol montre que la taille des pores et le débit de prélèvement contribuent de manière significative aux incertitudes et nécessitent un contrôle pour améliorer la précision de l’efficacité. En outre, le facteur de correction de Cunningham est également un paramètre de sensibilité. Sur la base du développement ci-dessus du système d’échantillonnage MPS, une méthode quantitative est proposée pour caractériser la concentration de masse élémentaire des particules micrométriques en suspension dans l’air par échantillonnage de particules etTEM - Energy Dispersive X-ray Spectroscopy (EDS). Le principe est de collecter les particules en suspension dans l’air sur une grille TEM, puis d’y ajouter une certaine masse de particules de référence, et de déterminer les pourcentages relatifs de tous les éléments (particules de référence et particules inconnues) via EDS. Indépendamment de la condition d’échantillonnage, la collecte quantitative et homogène des particules monodispersées RbCl, CsCl et NaCl sur la grille TEM a pu être réalisée. Pour toutes les conditions testées, lors du dépôt de divers types de particules en suspension quantifiées sur une grille TEM, les écarts absolus entre les pourcentages de masse des éléments théoriques et les rapports expérimentaux mesurés par EDS restent inférieurs à 10%, qui confirme que la méthode proposée pourrait être utilisée pour la caractérisation massique d’éléments dans un aérosol inconnu. Le RbCl a été préféré comme référence depuis sa rareté dans les particules aéroportées habituelles et sa faible toxicité
Characterization and analysis of airborne solid nano/micrometric particles have received considerable attention. The representative collection of particles to be analyzed is a fundamental requirement. The recently developed aerosol sampler called Mini Particle Sampler (MPS), which is equipped with a porous Transmission Electron Microscopy (TEM) grid, renders particle sampling convenient. However, the research for this useful sampling system is still in the initial stage. The thesis improves and quantifies the MPS sampling system. Besides, a new method of pollutant mass characterization is developed based on the optimizedsampling system. The sampling efficiency of the sampling system for particles with mobility diameters ranging from 5 to 100 nm is mainly investigated. According to the sensitivity analysis tof the parameters in the whole setup carried out by the Taguchi method, salt concentration of the atomizer, high-voltage polarity in the Differential Mobility Analyzer (DMA), sampling efficiency assessment method, sampling temperature, and porosity of the porous TEM gridminimally affect the collection efficiency. Small filter pore size, high flowrate, and denserparticles promote particle capturing, which are the main parameters. Based on the investigation of the filtration mechanisms of TEM grids and the comparison of available theoretical models, a method for experimental collection efficiency analysis combined with theoretical modeling is developed by considering the model’s applicability. Using this method, the effects of the main parameters mentioned above are compared between experiments andtheories. The sampling technology is optimized and the minimum collection efficiency isup to 40% by adjusting the parameter settings of the sampling system. In addition, accordingto the Monte-Carlo methods, sampling efficiency uncertainties from measured data andtheoretical models are generally less than 1% and 9%, respectively. Most sampling efficienciesmeasured data are covered by the efficiency uncertainty range simulated by models.Sobol variance-based sensitivity analysis shows that pore size and flowrate contribute significantly to the uncertainties, and require control to improve the efficiency precision. Besides, Cunningham correction factor is also a sensitivity parameter. Based on the above development of the MPS sampling system, a quantitative method is proposed to characterize the elemental mass concentration of airborne nano/micrometric particles via particle sampling and TEM - Energy Dispersive X-ray Spectroscopy (EDS). The principle is to collect airborne particles on a TEM grid, then add a certain mass of reference particles on it, and determine the relative percentages of all elements (reference and unknown particles) via EDS. Regardless of the sampling condition, the quantitative and homogeneously collection of monodisperse RbCl, CsCl, NaCl particles on the TEM grid could be achieved. For all the tested conditions, when depositing divers kinds of quantified airborne particles on one TEM grid, the absolute deviations between theoretical element mass percentages and experimental ratios measured by EDS remain lower than 10%, which confirms that the proposed method could be used for mass characterization of elements in an unknown aerosol. RbCl has been preferred as a reference since its rarity in usual airborne particles and having a low toxicity. The developed method has been used for characterizing aerosol released by the friction between serial pad and braking disc. The mass concentration of Fe in the braking aerosol is calculated as 0.105 μg/L using this method, which is consistent with the concentration range estimated from the data of Scanning Mobility Particle Sizer (SMPS) and Aerodynamic Particle Sizer (APS)

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Hancock, Jared M. « Formation and Analysis of Zinc Oxide Nanoparticles and Zinc Oxide Hexagonal Prisms and Optical Analysis of Cadmium Selenide Nanoparticles ». BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3867.

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In this dissertation, methods to synthesize ZnO are reported. First, zinc oxide nanoparticles were synthesized with small amounts of transition metal ions to create materials called dilute magnetic semiconductors (DMS). We employed a low temperature sol-gel method that produces ZnO nanoparticles of reproducible size and incorporates cobalt, nickel, and manganese ions into the nanoparticles. Conditions were controlled such that a range of amounts of Co, Ni, and Mn were incorporated. The incorporation was tracked by color changes in the white ZnO powder to blue for Co, green for Ni and yellow for Mn. XRD measurements showed the nanoparticles were on the order of 10 nm in diameter and had a wurtzite structure. Magnetic measurements showed a change from diamagnetic to paramagnetic behavior with increasing concentration of metal dopants. Second, formation of ZnO single crystal hexagonal prisms from a sol-gel method is presented. The method required water, zinc acetate, and ethanolamine to create a gel of zinc hydroxide and zinc hydroxide acetate, which upon heating formed single crystal hexagonal prisms. Characterization of the gel was done by XRD as well as XRD high temperature chamber (HTK) to determine the role of temperature in prism formation. SEM images showed hexagonal prisms were of uniform size (0.5 × 2 µm.) TEM and electron diffraction images showed a change from randomly oriented particles to an ordered single crystal after heating. Water and the acetate salt of zinc proved to be critical to prism formation. Lastly, we report absorption and fluorescence properties of synthesized oligothiophenes and oligothiophene-ruthenium complexes that are bound to CdSe nanoparticles. Their ability to act as sensitizers and charge transfer junctions was tested. It was found that fluorescence of CdSe nanoparticles was quenched when they were bound to the oligothiophenes, and that the fluorescence of the oligothiophenes was also quenched. The fluorescence lifetimes of the quenched species were shortened.

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Schlager, Kurt L. « The analysis and optimization of bow-tie and TEM horn antennas for pulse radiation using the finite-difference time-domain method ». Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/12915.

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Kaiser, Julian Winfried. « Structural and catalytic analysis of gold-palladium composite nanoalloys ». Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2013. http://dx.doi.org/10.18452/16693.

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In der vorliegenden Arbeit wurden facettierte Nanolegierungen aus Gold und Palladium in der Größenordnung von 1 – 3 nm synthetisiert und charakterisiert. Die Synthese erfolgte in sphärischen Polyelektrolytbürsten (SPB), welche als Stabilisatorsystem fungierten. Die Strukturaufklärung erfolgte mittels hochauflösender Transmissionselektronenmikroskopie (HR-TEM) und Extended X-ray Absorption Fine Structure (EXAFS) Spektroskopie. Die Nanolegierungen wurden als Katalysatoren zur Reduktion von 4-Nitrophenol verwendet, wobei eine gesteigerte katalytische Aktivität, im Vergleich zu monometallischen Nanopartikeln, beobachtet wurde. Im HR-TEM wurden auf den Kanten der Metallkristalle Oberflächendefekte in Form von Stufen sichtbar, wobei eine Korrelation der Oberflächendefekte zur katalytischen Aktivität hergestellt wurde. Durch EXAFS-Analysen konnte nachgewiesen werden, dass eine Zusammensetzung von 75 mol-% Gold und 25 mol-% Palladium annähernd eine statistische Mischung aufweist. Mit steigendem Palladiumgehalt wurde eine leichte Anreicherung von Palladium an der Oberfläche der Partikel, sowie nichtmetallisches Palladium der Oxidationsstufe 2+ gefunden. Diese unterschiedliche Anordnung der Elemente für verschiedene Zusammensetzungen korreliert ebenfalls mit der katalytischen Aktivität. Ferner konnte eine Kontraktion des Netzebenenabstands für kleine Partikel mittels EXAFS nachgewiesen werden. Bei der Verwendung als Katalysatoren wurde eine zeitliche Reaktionsverzögerung festgestellt, welche auf die Oberflächenrestrukturierung der Metallnanopartikel hinweist. Zusätzlich konnte durch den Vergleich von SPB stabilisierten und stabilisatorfreien Goldnanopartikeln festgestellt werden, dass das SPB System die katalytische Aktivität nicht signifikant beeinträchtigt.
In this work facetted gold-palladium nanoalloys have been synthesized and characterized in the range of 1 – 3 nm. The spherical polyelectrolyte brushes (SPB) have been used during synthesis and for stabilization of the nanoparticles. Structural analyses have been done by high resolution transmission electron microscopy (HR-TEM) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The nanoalloys have been used as catalysts for the reaction of 4-nitrophenol, where an enhanced catalytic activity has been found compared to monometallic nanoparticles. Surface defects are visible by steps at the edge of the metallic crystal where a correlation of these surface defects and the catalytic activity has been found. By EXAFS spectroscopy an almost statistic mixture for a composition of 75 mol-% gold and 25 mol-% palladium, slight enrichment of palladium at the surface of the particle, and the presence of nonmetallic palladium with an oxidation number of 2+ has been observed. This different atomistic arrangement correlates with the catalytic activity as well. In addition, a contraction of the lattice parameter has been observed for small particles by EXAFS measurements. Using the nanoalloys as catalyst, a delay time for the reaction has been found which indicates a restructuring of the surface of the metal nanoparticles. By comparison of SPB stabilized and support-free gold nanoparticles no significant influence of the SPB system on the catalytic activity has been observed.

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Västerlund, Emma, et Ronja Flink. « Analysis and characterization of environmental friendly trivalent chromium passivation of aluminum alloys ». Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129351.

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As of 21st September 2017, industrial use of hexavalent chromium (Cr(VI)) will, due to its environmental toxicity and carcinogenicity, be restricted by REACH regulations. Saab Aeronautics is therefore shifting anticorrosion surface treatment of aluminum alloys from hexavalent chromium conversion to trivalent chromium (Cr(III)) passivation. The purpose of this thesis is to investigate the characteristics of conversion coatings formed with the passivation chemical SurTec 650V, in order to facilitate transfer to the more environmental friendly alternative. Process parameters, such as pH and immersion time in SurTec 650V passivation baths, have been investigated for passivation of three different aluminum alloys; 2024, 6061 and 7075. The characteristics of the Cr(III) conversion coatings achieved at laboratory scale in the thesis work have been compared with SurTec 650V process in production scale and with Cr(VI) containing Alodine 1200 and Alodine 1500 processes. The impact of varying process parameters have been investigated with goniometry, x-ray photoelectron spectroscopy (XPS), auger electron spectroscopy (AES), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to analyse characteristics of the conversion coatings. Differences in chemical composition on the surface and in depth profile was detected with XPS and AES, respectively and topology of coatings was found to differ for different aluminium alloys and parameter combinations. With TEM, the thickness of the conversion coating was found to be approximately 30-50 nm, which is thinner than the coatings formed with Cr(VI) passivation. Characteristics of coatings formed with Cr(III) passivation is concluded to be very dependent on parameter variation, especially for alloy 2024. Differences also occur between passivation at laboratory and production scale. Further evaluation of the production scale SurTec 650V process and corrosion testing should be performed, and an elaboration of a process control is required before the shift to an environmental friendly passivation process can be completely successful at Saab.

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Bačo, Ondřej. « Návrh projektorové soustavy transmisního elektronového mikroskopu pro metodu Single Particle Analysis ». Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417155.

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Předkládaná práce se zabývá návrhem projektorové soustavy transmisního elektronového mikroskopu (TEM) pro metodu single particle analysis (SPA). Návrh projektorové soustavy byl vytvořen v programu Electron Optical Design (EOD) verze 4.020. Série buzení jednotlivých čoček pro zvětšení projektorové soustavy v rozsahu od 50 do 10000 byla vypočítaná pomocí přístupu využívajícího aproximaci tenké čočky, dále pomocí přístupu využívajícího aproximaci tlusté čočky, metodou linearního zaostření v programu EOD a metodou nelineárního zaostření v programu EOD ve verzi 5.003. Dosažené výsledky byly porovnány a ověřeny pomocí reálného trasování částic v programu EOD.

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Duarte, Larissa Costa. « “A AIDS tem um rosto de mulher” : discursos sobre o corpo e a feminização da epidemia ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180935.

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Desde sua eclosão na década de 1980 na forma de epidemia, a AIDS tem sido principalmente associada a homossexuais masculinos: inicialmente partindo da literatura médica, essa visão espalhou-se também para o público leigo e mantém-se viva no imaginário popular, ainda que, a partir da década de 1990, tenha havido um movimento para reconhecer a parcela cada vez mais vitimada pela síndrome: mulheres heterossexuais. A essa progressão, deu-se o nome de feminização do HIV/AIDS, uma narrativa sobre uma suposta mudança no perfil da epidemia. No entanto, é possível encontrar informações sobre ocorrências da doença em mulheres desde muito antes, e é por meio de uma análise discursiva acerca do tema que este trabalho nasce: embora a epidemia da AIDS nunca tenha deixado de ter mulheres como parte expressiva de seus portadores, os discursos e narrativas desde 1980 vêm sistematicamente falhando em incluí-las e direcionar políticas de prevenção e combate que levem em consideração as particularidades das vivências femininas ou a complexidade de sua vulnerabilidades – parte de um sistema intricado de influência bidirecional entre cultura e materialidade. Utilizando metodologias, conceitos e textos de diversas áreas de produção de conhecimento, me proponho a analisar a inserção do corpo feminino na narrativa da epidemia HIV/AIDS privilegiando a historicidade e as diferentes versões desse objeto.
Since its occurrence in the 1980s in epidemic form, AIDS has been mainly associated to homosexual males: initially put forth by medical literature, this view spread to the non-expert audience as well and is kept alive in people’s imaginations, even though by the 1990s there has been a movement towards recognizing the group increasingly victimized by the syndrome: heterosexual women. This progression has been dubbed feminization of HIV/AIDS, a narrative about a supposed change in the profile of the epidemic. However, it is possible to find information about occurrence of the disease in women since much earlier, and it is through a discoursive analysis around the subject that this work came to be: even though the AIDS epidemic has never been without women as an expressive part of its carriers, mainstream discourse and narratives have since the 1980s systematically failed to include them and direct prevention and treatment politics that take into account particularities of femalehood or the complexity of its vulnerabilities – part of an intricate system of bidirectional influence between culture and materiality. By using methodologies, concepts, and texts from several fields of generation of knowledge, I propose to analyze the insertion of the female body in the HIV/AIDS epidemic focusing on the historicity and the different versions of this object.

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Karathanou, Argyro. « Image processing for on-line analysis of electron microscope images : automatic Recognition of Reconstituted Membranes ». Phd thesis, Université de Haute Alsace - Mulhouse, 2009. http://tel.archives-ouvertes.fr/tel-00559800.

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The image analysis techniques presented in the présent thesis have been developed as part of a European projeet dedicated to the development of an automatic membrane protein crystallization pipeline. A large number of samples is simultaneously produced and assessed by transmission electron microscope (TEM) screening. Automating this fast step implicates an on-fine analysis of acquired images to assure the microscope control by selecting the regions to be observed at high magnification and identify the components for specimen characterization.The observation of the sample at medium magnification provides the information that is essential to characterize the success of the 2D crystallization. The resulting objects, and especially the artificial membranes, are identifiable at this scale. These latter present only a few characteristic signatures, appearing in an extremely noisy context with gray-level fluctuations. Moreover they are practically transparent to electrons yielding low contrast. This thesis presents an ensemble of image processing techniques to analyze medium magnification images (5-15 nm/pixel). The original contribution of this work lies in: i) a statistical evaluation of contours by measuring the correlation between gray-levels of neighbouring pixels to the contour and a gradient signal for over-segmentation reduction, ii) the recognition of foreground entities of the image and iii) an initial study for their classification. This chain has been already tested on-line on a prototype and is currently evaluated.

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Oliver, Fojkar. « Azotofiksirajuće cijanobakterije u zemljištima Vojvodine i njihova ultrastrukturna i genetička karakterizacija ». Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=101459&source=NDLTD&language=en.

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U radu je ispitana zastupljenost azotofiksirajućih cijanobakterija, ukupnog broja algi i ukupnog broja bakterija u različitim tipovima zemljišta na jedanaest lokaliteta u Vojvodini, od čega se sedam nalaze u zaštićenim prirodnim dobrima. Ispitana je brojnost u zavisnosti od dubine pedološkog profila, kao i od godišnjeg doba. Izvršena je izolacija sojeva azotofiksirajućih cijanobakterija, određena njihova taksonomska pripadnost i osnovne citološke karakteristike. Ispitana je ultrastruktura vegetativnih ćelija, heterocista i spoljnih struktura na ćelijama fimbrije i pili, transmisionim elektronskim mikroskopom. Izvršena je genetička karakterizacija izolovanih sojeva azotofiksirajućih cijanobakterija PCR metodom analizom STRR fragmenata DNA.Brojnost azotofiksirajućih cijanobakterija i ukupna brojnost algi je bila znatno veća kod hidromorfnih i halomorfnih zemljišta, nego kod automorfnih zemljišta. Najveća prosečna godišnja brojnost azotofiksirajućih cijanobakterija, u površinskom sloju 0-5cm, je utvrđena kod zemljišta fluvisol u SRP “Koviljsko petrovaradinskom ritu”, 150864 jedinki po gramu apsolutno suvog zemljišta. Zemljište sa najnižom brojnošću azotofiksirajućih cijanobakterija, je gajnjača u NP Fruška gora, 1582 jed./gr zemljišta u površinskom sloju.Kod svih ispitivanih zemljišta brojnost azotofiksirajućih cijanobakterija je bila najveća u površinskom sloju zemljišta, 0-5 cm dubine, opadala je sa dubinom zemljišta i bila najmanja u najdubljem sloju, 30 - 60 cm. Kod najvećeg broja ispitivanih zemljišta brojnost azotofiksirajućih cijanobakterija je bila najveća tokom zimskog perioda. Azotofiksirajuće cijanobakterije su dominantne u našim zemljištima i zastupljene sa 56.27% u odnosu na druge grupe algi.Izolovano je 30 sojeva azotofiksirajućih cijanobakterija: 19 sojeva Nostoc-a, 4 soja Anabaena, 4 Cylindrospermum, i po jedan soj Calothrix, Tolypothrix i Phormidium. Prosečna zastupljenost heterocista, ćelija koje vrše azotofiksaciju, kod roda Nostoc je iznosila 8.28%, Anabaena 4.25%, Cylindrospermum-a 2.93%, Calotrix elenkinii 6.19% i Tolypothrix 7.76%.Ultrastrukturnim ispitivanjem, TEM mikroskopom, vegetativnih ćelija azotofiksirajućih cijanobakterija uočili smo inkluzije redovnog pojavljivanja: karboksizome (Cs), cijanoficinkse granule (CG), polifosfatne granule (PG), ribozome (R), lipidne granule (ß –granule) i tilakoide (T), kao i inkluzije neredovnog pojavljivanja: membranom ograničene kristalne inkluzije.Koristeći TEM i tehniku bojenja ćelija sa RR i ultratankih preseka utvrdili smo prisustvo omotača od fimbrija kod tri soja (A.314, A.azollae i N.302) i tipične fimbrije kod dva soja (N.311 i N.9229). Metodom negativnog bojenja NS PTA uočili smo takođe tipične fimbrije, igličastog-dlakastog izgleda, jasnih granica niti kod tri soja (N.302, N.7901 i N.9229), međutim uočili smo i atipične sluzne fimbrije, koje nemaju jasno izražene granice, ali su veoma moćno raširene oko vegetativnih ćelija, kod tri soja (A.314, A.azollae, N.311).Kod simbiotskih-infektivnih sojeva N.7901 i N.9229 javljaju se samo tipične fimbrije iz prve klase, a kod diazotofnih sojeva i simbiotskog - neinfektivnog soja A.azollae javljaju se atipične-sluzne fimbrije iz druge klase.Za ispitivanje sličnosti cijanobakterija metodom PCR-a pomoću STRR konzervativnih sekvenci DNA genoma korišćeno je 39 sojeva azotofiksirajućih cijanobakterija i kod 38 je utvrđeno njihovo prisustvo. Svi sojevi se mogu podeliti u tri grupe, klastera. Prvi klaster je najveći i obuhvata 24 soja i deli se na dva podklastera: Ia koji obuhvata 12 sojeva gde dominiraju sojevi Nostoc-a (8), i podklaster Ib koji obuhvata takođe 12 sojeva, od čega 6 sojeva pripada rodu Anabaena. Podklaster Ia i podklaster Ib pokazuju različitost od 90%. Sva tri simbiozna, infektivna, soja Nostoc-a se nalaze u klasteru I: N.7901, N.9229 i N. 8001. Svaki simbiozni soj Nostoc-a ima genetske sličnosti sa po jednim diazotrofnim sojem Nostoc-a izolovanim iz zemljišta Vojvodine.Klaster II obuhvata sedam (7) sojeva među kojima dominiraju sojevi Cylindrospermum-a, dok klaster III obuhvata 7 sojeva od čega 6 pripadaju rodu Nostoc, a jedan rodu Rivularia.Detaljno poznavanje svojstava izolovanih azotofiksirajućih cijanobakterija doprineće njihovoj budućoj primeni kako u proizvodnji ratarskih i povrtarskih kultura, tako i u biotehnološkoj proizvodnji
In this study examined is the frequency of nitrogen-fixing cyanobacteria, total number of algae and total number of bacteria in different soil types on eleven localities in the Vojvodina Province. Seven out of those eleven localities are found in protected nature reserves. Actually, studied was the number of the cyanobacteria and algae depending on the depth of pedological characterization as well as on season. First, isolated were the types of nitrogen-fixing cyanobacteria, determined was their taxonomic origin and basic cytological characteristics. Also examined was the ultrastructure of vegetative cells, heterocysts and other outer structures on fimbriae and pili cells using TEM, transmission electron microscope. Finally, performed was the genetic characterization of isolated types of nitrogen-fixing cyanobacteria using the PCR method and analyzing STRR fragments of DNA.The presence of nitrogen-fixing cyanobacteria and total number of algae was significantly higher with hydromorphic and halomorphic soils than with authomorphic ones. Highest annual average number of nitrogen-fixing cyanobacteria in the topsoil (0-5 cm) was reported with fluvisol soil in Special Nature Reserve „Koviljsko petrovaradinski rit” (Swamp) and there were 150864 units of bacteria per gram of absolutely dry soil. The soil with the lowest presence of nitrogen-fixing cyanobacteria recorded was cambisol in National Park “Fruska gora” with 1582 units per gram of soil in the topsoil.With all the researched types of soils the number of nitrogen-fixing cyanobacteria was in the topsoil, 0-5 cm of depth and decreased in line with the depthof soil and lowest was at the deepest layer, 30-60cm. The highest frequency of nitrogen-fixing cyanobacteria was found during the winter season with most of the examined soils. Nitrogen-fixing cyanobacteria are the dominant type of bacteria in our soils and are presented with 56, 27% compared to other types of algae.30 strains of nitrogen-fixing cyanobacteria were isolated: 19 types of Nostoc sp., 4 of Anabaena sp. and one in each genus of Calothrix, Tolypothrix and Phormidium.Using ultrastructural examination and TEM microscope when studying vegetative cells of nitrogen-fixing cyanobacteria observed were the inclusions of regular frequency: carboxysomes (Cs), cyanophycin granules (CG) , polyphosphate granules (PG), ribosomes (R), lipid granules (SS -granule ) and thylakoids ( T ) as well as the inclusion of irregular occurrence: a membrane-bound crystal inclusions.Using TEM technique and staining the cells with the RR and ultra thin cross section, we determined the presence of depletion of the fimbriae with three strains (A.314, A.azollae and N.302) and typical fimbriae with the two strains (N.311 and N.9229). Applying the method of negative staining NS PTA also noticed were a typical fimbriae, needle-hairy like looks with clear boundaries with the three strains (N.302, N.7901, N.9229). However, also observed were atypical mucous fimbriae, which do not have clearly expressed borders, but they are very strongly spread around the vegetative cells, with the three strains (A.314, A.azollae, N.311).With symbiotic - infective strains N.7901 and N.9229 only typical fimbriae of first class occurred, and in diazotroph strains and symbiotic – non infectious strain A. azollae found were atypical mucous fimbriae of second class.To test the similarity of cyanobacteria by PCR method and using a STRR - conservative DNA sequence of the genome used were 39 strains fixing cyanobacteria and with 38 established was their presence. All strains can be divided into three groups of clusters. The first cluster is the largest and covers 24 strains, and is divided into two subclusters: Ia which includes 12 strains,where predominant are Nostoc strains ( 8 ) , and subcluster Ib , which also implies 12 strains , out of which 6 strains belong to the genus Anabaena. Subcluster Ia and Ib show a difference of 90 %. All three symbiotic , infectious Nostoc strains are classified in a cluster I: N.7901, N.9229 and N. 8001. Each symbiotic Nostoc strain has a genetic similarity with one di-nitrogen Nostoc strain isolated from a lot of different soils in Vojvodina.Cluster II includes seven (7) strains , including strains among which the predominant are Cylindrospermum ones , while cluster III includes 7 strains of which 6 belong to the genus Nostoc and one to genus Rivularia.Detailed knowledge of the properties of isolated fixing cyanobacteria could contribute to their future application both in the production of field crops and vegetables, as well as in biotechnological production.

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FANTINI, MARCO. « From in vitro evolution to protein structure ». Doctoral thesis, Scuola Normale Superiore, 2020. http://hdl.handle.net/11384/91067.

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In the nanoscale, the machinery of life is mainly composed by macromolecules and macromolecular complexes that through their shapes create a network of interconnected mechanisms of biological processes. The relationship between shape and function of a biological molecule is the foundation of structural biology, that aims at studying the structure of a protein or a macromolecular complex to unveil the molecular mechanism through which it exerts its function. What about the reverse: is it possible by exploiting the function for which a protein was naturally selected to deduce the protein structure? To this aim we developed a method, called CAMELS (Coupling Analysis by Molecular Evolution Library Sequencing), able to obtain the structural features of a protein from an artificial selection based on that protein function. With CAMELS we tried to reconstruct the TEM-1 beta lactamase fold exclusively by generating and sequencing large libraries of mutational variants. Theoretically with this method it is possible to reconstruct the structure of a protein regardless of the species of origin or the phylogenetical time of emergence when a functional phenotypic selection of a protein is available. CAMELS allows us to obtain protein structures without needing to purify the protein beforehand.

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Fonseca, Fábio Carlos de Mattos da. « Estudos para composição do eu e do(s) outro(s) : enunciação, polifonia e imagens discursivas na cartilha da Campanha Nacional O Petróleo Tem que Ser Nosso ». Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2258.

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O anúncio dos gigantescos campos do pré-sal brasileiro recolocou o petróleo no alvo dos holofotes. A propriedade desta imensa riqueza e as inevitáveis mudanças na legislação do setor são as principais questões que derivam deste fato. Com efeito, temos assistido a uma proliferação de discursos acerca do tema. Esta dissertação se insere num conjunto de reflexões que tomam o petróleo como objeto de interesse. Privilegiamos um espaço específico de produção discursiva, a saber, o instituído pela Campanha Nacional O Petróleo Tem que Ser Nosso. Um primeiro procedimento metodológico de coleta de dados possibilitou identificar que, entre os seus materiais de mobilização, ganha destaque a cartilha de massas do movimento, que desde julho de 2009 circula pelo território nacional. Inscritos numa perspectiva da Análise do Discurso de base enunciativa, cuidamos de construir uma reflexão sobre alguns dos modos de inscrição do(s) sujeito(s) no discurso. Nossas considerações acerca dos gêneros do discurso revelaram o hibridismo da cartilha; tal peculiaridade nos obrigou a construir dispositivos distintos de análise. Num primeiro memento, decidimos observar as marcas de pessoa, os marcadores temporais e espaciais, com vistas a identificar uma dada cenografia discursiva (Maingueneau, 1997) que nos remetesse às imagens dos coenunciadores; consideramos, num segundo momento, os discursos relatados (Bakhtin, 2006; Authier-Revuz, 1998 e outros) para compreender a polifonia inerente à cartilha. Nossa análise verificou de que maneira um regime de verdade e uma memória se instituem pela cenografia discursiva; a análise dos discursos relatados, com ênfase nos discursos direto, indireto e narrativizado, nos permitiu identificar, no agenciamento das vozes, um espaço de confronto entre formações discursivas divergentes
The announcement of the giant fields in the Brazilian pre-salt oil has put the target in the spotlight. The immense wealth and property of the inevitable changes in the legislation of the sector are the main issues arising from this fact. Indeed, we have witnessed a proliferation of discourses on the subject. This work is part of a set of reflections that take oil as an object of interest.We favor a specific space of discursive production, namely that introduced by the National Campaign The Oil Must Be Ours. A first methodological approach to data collection identified that, among its mobilization materials, is highlighted by the primer mass movement, which runs from July 2009 through the national territory. Subscribers perspective of discourse analysis based expository take care to build a reflection on some of the modes of entry (s) of subject (s) in the speech. Our considerations regarding the speech genres revealed hybridization of the primer, such peculiarity forced us to build devices for different analysis. In a first memento, we decided to observe the marks of a person, the temporal and spatial markers, in order to identify a particular scenery discursive (Maingueneau, 1997) which took us to images of coenunciadores; consider, second, the speeches reported (Bakhtin, 2006; Authier-Revuz, 1998 and others) to understand the polyphony inherent in the booklet. Our analysis shows how a regime of truth and memory are instituted for the scenography discourse, the discourse analysis reported, with emphasis on speeches direct, indirect and narrativised allowed us to identify, in the assemblage of voices, a place of confrontation between formations discursive differences

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Gorbatchev, Olga. « Etude des nouveaux modificateurs de frottement à base de molybdène pour la lubrification moteur ». Thesis, Ecully, Ecole centrale de Lyon, 2014. http://www.theses.fr/2014ECDL0020/document.

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La zone Segment-Piston-Chemise (SPC) d’un moteur thermique est une source importante de dissipation d’énergie liée au frottement sévère. Il est important d’optimiser les lubrifiants agissant dans cette zone car ils ont un impact essentiel sur la durée de vie des pièces mécaniques et la réduction de la consommation énergétique des véhicules. Le dépôt de revêtements sur certaines pièces soumises à des frottements sévères est également une alternative intéressante, en particulier les revêtements carbonés de type DLC et diamant nanocristallin (NCD). La formulation des nouveaux lubrifiants moteurs doit tenir compte de la présence éventuelle de ces nouveaux matériaux. Dans ce travail de doctorat, l’action tribochimique de nouveaux additifs à base de molybdène, couplés à un additif anti-usure de type ZnDTP et à d’autres additifs de type modificateur de frottement, a été étudiée. Ces derniers sont depuis longtemps connus pour leur grande capacité à réduire le frottement grâce à la formation du composé lamellaire di-sulfure de molybdène (MoS2), notamment les additifs MoDTC dimer. Cependant la quantité importante de soufre qu’ils contiennent reste problématique du fait de son impact néfaste sur l’environnement. L’effet synergique d’un additif au molybdène purement organique, appelé Mo-organique, en combinaison avec un additif ZnDTP et d’une triamine grasse, a été découvert. Ce nouveau mélange ternaire permet de réduire jusqu’à 20% la contenance en soufre d’une formulation lubrifiante globale tout en améliorant les performances tribologiques par rapport à celles du MoDTC classique. De ce fait, une réduction du coefficient de frottement atteignant 50% a été observée. Une caractérisation physico-chimique multi-échelles des tribofilms binaires et ternaires dérivés du Mo-organique a été réalisée en utilisant une approche multi-techniques (XPS, ToF-SIMS, FIB/HRTEM). Un mécanisme réactionnel hypothétique conduisant à la formation du MoS2, passant par un composé intermédiaire de type « thiomolybdate » a été proposé
The friction in the Piston-ring area is a significant cause of the energy waste. It is important to optimize the lubricants acting in this zone because they have an essential impact on the service life of the mechanical parts and the reduction of the energy consumption of vehicles. The coating on relevant part is also an interesting alternative, such as the carbon coating of the DLC type or a nano-crystalline diamond (NCD) coating. If such coating materials are used, the composition of new lubricants has to be adapted correspondingly. This doctoral work-studies the tribo-chemical action of new additives with molybdenum, coupled with an anti-wear additive of the ZnDTP type as well as with some other friction-modifying additives. Some of these additives, especially the MoDTC dimer, are known to reduce the friction through formation of the lamellar di-sulfur composite of molybdenum (MoS2). However, due to high sulfur content these additives produce significant adverse environmental effects. A synergy effect has been proven of a purely organic molybdenum additive, called Moorganic, combined with a ZnDTP additive and from a fatty triamine. This new ternary mixture allows reducing up to 20% the sulfur content in the lubricant’s global formula and improves the tribological properties in comparison with the classical MoDTC. Consequently, the observed reduction of friction coefficient reached 50%. Using the multi-technic approach (XPS, ToF-SIMS, FIB/HRTEM) we realized a multi-scale physicochemical characterization of the binary and ternary tribo-layers that derived from the Mo-organic. A reactional mechanism that leads to the MoS2 formation has been proposed; it goes through the intermediate composite of the « thiomolybdate » type

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Gentner, Janene Margaret. « Tissue analysis : multidisciplinary approach using FT-IR microspectroscopy and visual microscopy ». Thesis, Queensland University of Technology, 2001.

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Silva, Rondineli Mendes da. « Programa Aqui tem Farmácia Popular : expansão entre 2006-2012 e comparação com os custos da assistência farmacêutica na Secretaria Municipal de Saúde do Rio de Janeiro ». Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7554.

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Em 2004 o governo federal anunciou um novo mecanismo para melhorar o acesso da população brasileira aos medicamentos, chamado de "Programa Farmácia Popular do Brasil" (PFPB) que disponibiliza um rol de produtos subsidiados pelo governo, utilizando ou não sistema de copagamento. O PFPB está dividido em três vertentes: (a) no setor público, chamada Rede Própria; (b) expansão em 2006, com o comércio farmacêutico denominado "Aqui Tem Farmácia Popular" (ATFP) e; (c) isenção de copagamento, em 2011, em todas as farmácias no âmbito do Programa, para anti-hipertensivos, antidiabéticos e antiasmáticos. Este estudo examinou o modelo de provisão de medicamentos na versão ATFP, comparando-o ao tradicionalmente praticado na Secretaria Municipal de Saúde do Rio de Janeiro (SMS-Rio), com vistas a avaliar seus custos para os setores públicos envolvidos. Foram levantados os gastos do Ministério da Saúde (MS) com pagamentos no Programa ATFP em fontes secundárias, como o Fundo Nacional de Saúde e a Sala de Apoio à Gestão Estratégica, de 2006 a 2012. Dados sobre o volume de pagamentos por medicamentos, perfil dos usuários atendidos e unidades farmacotécnicas (UF) dispensadas foram mapeados por contato direto com o Sistema Eletrônico do Serviço de Informações ao Cidadão. Estimativas dos custos da SMS-Rio, com aquisição, logística e dispensação de 25 medicamentos, restritas ao ano de 2012, foram realizadas. No período ocorreu forte expansão do Programa ATFP, tanto de unidades credenciadas, como de municípios cobertos, de 750% e 528%, respectivamente. Gastos federais com medicamentos no ATFP foram de aproximadamente R$ 3,4 bilhões, em valores ajustados para 31/12/2012. Houve inversão do fluxo dos pagamentos para entidades com matriz fora das capitais, representando aumento da capilaridade do Programa, e relativa concentração de pagamentos em grandes redes varejistas. No município do Rio de Janeiro, estes gastos foram superiores a R$ 260 milhões e, desde 2008, são maiores que as transferências do MS para aquisição de medicamentos básicos. Custos comparativos entre o menor Valor de Referência (VR) do Programa ATFP, e o custo estimado por UF na SMS-Rio dos medicamentos mostrou-se, na média geral, quase 255% vezes maior que o custo municipal. A comparação de custo foi mais favorável à SMS-Rio em 20 dos 25 itens comuns. Simulação considerando a demanda de cada medicamento consumido pela SMS-Rio em 2012 mostrou que, se a municipalidade os adquirisse pelo menor VR, incorreria em mais de R$ 95 milhões no custo global para os mesmos 25 produtos. O programa ministerial representou melhoria no acesso a medicamentos, mas os gastos expressivos repercutem em sua interface com o sistema descentralizado de financiamento da assistência farmacêutica. Alguns dos VR poderiam ser objetos de exame e avaliação, frente aos custos sistematicamente mais favoráveis nos valores levantados para a SMS-Rio.

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Esaki, Shogo. « Cycle performance improvement of LiMn2O4 cathode material for lithium ion battery by formation of “Nano Inclusion” ». Kyoto University, 2016. http://hdl.handle.net/2433/215650.

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著作権、出典、利用制限の表示を出版社より求められている。
Kyoto University (京都大学)
0048
新制・課程博士
博士(エネルギー科学)
甲第19824号
エネ博第330号
新制||エネ||66(附属図書館)
32860
京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻
(主査)准教授高井茂臣, 教授萩原理加, 教授佐川尚
学位規則第4条第1項該当

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Nylén, Ulf. « Ring-opening catalysts for cetane improvement of diesel fuels ». Doctoral thesis, KTH, Kemiteknik, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-537.

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The global oil refining industry with its present product distribution essentially shifted towards fuels such as gasoline and diesel will most likely hold the fort for considerable time. However, conditions are changing and refinery survival will very much depend on long-term planning, process and product flexibility and being at the frontiers of refining technology, a technology where catalysts play leading roles. Today oil refiners are faced with the challenge of producing fuels that meet increasingly tight environmental specifications, in particular with respect to maximum sulphur content. At the same time, the average quality of crude oil is becoming poorer with higher amounts of aromatics, heteroatoms (sulphur and nitrogen) and heavy metals. In order to stay competitive, it is of decisive importance for refiners to upgrade dense petroleum fractions of low quality to highly value-added products. A practicable route, for example, is upgrading the catalytic cracking by-product Light Cycle Oil (LCO) into a high-quality diesel-blending component in a two-step catalytic process. In the first step the LCO is hydrotreated over a Pt Pd based acidic catalyst bringing about heteroatom and aromatic reduction and isomerization of C6 to C5 naphthenic structures. In the second step these naphthenic structures are selectively opened over an Ir-based catalyst to improve the cetane value. The present thesis is mainly devoted to the second catalytic step of LCO upgrading and was partly conducted within the framework of the European Union project RESCATS. From the patent literature it is evident that iridium-based catalysts could be good candidates for ring-opening purposes. A literature survey covering ring opening of naphthenic structures made in the beginning of the project (in 2001), showed the need for extending investigations to heavier hydrocarbons, more representative of the diesel fraction than model compounds such as alkylated mono C5 and C6 naphthenic rings frequently employed in previous academic studies. Ring-opening catalysts, mainly Pt-Ir based, were synthesised at KTH by two different techniques: the microemulsion and the incipient wetness techniques. Paper I is a review of the microemulsion technique and its applications in heterogeneous catalysis. Characterization of catalysts was performed employing a multitude of techniques including quantitative TPR, TEM-EDX, XPS, CO FT-IR, NH3-DRIFTS and XRF etc. Catalytic screening at 325 oC and atmospheric pressure with hydrogen and pure indan as model substance was conducted to investigate ring-opening activity in terms of conversion and selectivity to desired cetane-boosting products. This development process is the topic of Papers II-IV. The possible industrial implementation of the best catalyst candidate is demonstrated in Paper V. When designing a catalytic system aimed at refining petroleum, it is crucial to monitor the evolution of the sulphur distribution throughout the different stages of the process so that catalyst properties and reaction parameters may be optimised. The final section of this thesis and Paper VI are devoted to high-resolution sulphur-distribution analysis by means of a sulphur chemiluminescence detector (SCD) following gas chromatographic separation.
QC 20101014

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Jouanny, Emilie. « Étude de l'évolution microstructurale sous irradiation aux ions Ti2+ de deux alliages de titane : lien avec les propriétés mécaniques ». Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0071/document.

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Ce travail de thèse s’intéresse à l’évolution de la microstructure sous irradiation d’alliages de titane, en vue de leur potentielle utilisation dans le domaine du nucléaire. Une étude paramétrique (température, dose et flux d’irradiation) a donc été menée, à l’aide de simulations d’irradiations neutroniques par des irradiations aux ions (plateforme JANNuS – Saclay), sur les alliages T40 et TA6V, et de caractérisations microstructurales qualitatives et quantitatives post irradiation (MET, analyse d’image, SAT). Ainsi, différents défauts d’irradiation ont été identifiés. En particulier, la présence de boucles à composante dans l’alliage T40 et de précipités riches en vanadium dans l’alliage TA6V a clairement pu être mise en évidence dès la température de 300°C. La microstructure résultante est fortement dépendante des paramètres d’irradiation et de l’alliage de titane considéré. Un effet important de la température (entre 300°C et 430°C) a été noté sur les boucles de dislocations de type pour l’alliage T40 et sur les précipités pour l’alliage TA6V. Les doses et les flux considérés à 300°C ne modifient pas la distribution des défauts des deux alliages. A 430°C, l’augmentation de la dose modifie peu le paysage des boucles de dislocations de type pour l’alliage TA6V contrairement à l’alliage T40. Les précipités, quant à eux ne semblent pas affectés par l’augmentation de la dose. Une analyse des mécanismes mis en jeu est proposée. Enfin, des essais de nano-indentation ont permis une première description du lien microstructure / propriétés mécaniques. A 430°C, l'alliage T40 ne semble pas être impacté mécaniquement par l’évolution de la microstructure avec la dose d’irradiation contrairement à l'alliage TA6V
This PhD work deals with microstructural evolution of titanium alloys under irradiation, due to their potential use in the nuclear field. Parametric study (temperature, dose and irradiation flux) was conducted, using ion irradiations (JANNuS – Saclay platform) to simulate neutron irradiation damage. Two titanium alloys (CP Ti grade 2 and Ti-6Al-4V) were considered and qualitative and quantitative post irradiation microstructural characterizations were done (TEM, image analysis, APT). Thus, various irradiation defects were identified. In particular, presence of -component loops was highlighted in CP Ti grade 2 and vanadium-rich precipitates in Ti-6Al-4V from the temperature of 300°C. Resulting microstructure is hardly depending on irradiation parameters and considered titanium alloys. Important effect of temperature (between 300°C and 430°C) was noted on -type dislocation loops in CP Ti grade 2 and precipitates in Ti-6Al-4V. At 300°C, dose and flux have no effect on the defect distribution of the two titanium alloys. At 430°C, the increase of dose has a little consequence on the -type dislocation loops in Ti-6Al-4V, contrary to the ones observed in CP Ti grade 2. Precipitates, observed in Ti-6Al-4V, do not seem to be affected by the increase of the dose. Analysis of involved mechanisms is proposed. Finally, nano-indentation tests have allowed to get first description of the link between microstructure and mechanical properties. At 430°C, CP Ti grade 2 do not seem to be affected mechanically by the microstructural evolution with the irradiation dose, contrary to Ti-6Al-4V

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Engl, Karl. « TEM-Analysen an Gruppe III-Nitrid-Heterostrukturen ». Berlin Logos-Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2757169&prov=M&dok_var=1&dok_ext=htm.

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Košík, Juraj. « Determination of titanium dioxide nanoparticles in personal care products ». Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240803.

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Předkládaná diplomová práce se zabývá extrakcí nanočástic oxidu titaničitého z produktů osobní péče, konkrétně opalovacích krémů a následnou charakterizací těchto částic. Počet komerčně dostupných produktů s obsahem nanočástic TiO2 se neustále zvyšuje a to se sebou přináší potřebu vyhodnotit potenciální osud a nepřímou expozici TiO2 nanošástic o různých velikostí a tvarů a zkoumat jejich celý životní cyklus. Bylo zkoumáno použití ultrafiltrace a ultracentrifugace jako extrakční metody. Dvě metody pro extrakci TiO2 nanočástic byly vyvinuty a aplikovány na vzorky opalovacích krémů. Extrahované částice mohou být použity pro ekotoxikologické studie, případně experimenty v mesokosmu. Velikost částic byla stanovena pomocí metody dynamického rozptylu světla a transmisní elektronové mikroskopie.

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Meziani, Smaïl. « Influence du procédé de congélation sur les levures et les propriétés techno-fonctionnelles des pâtes sucrées (type Kougelhopf) ». Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL089N/document.

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Les pâtes surgelées sont relativement stables et peuvent être fabriquées à l’échelle industrielle, distribuées et cuites à la demande au moment de la vente ou de la consommation (point chaud). La congélation des pâtes sucrées induit une baisse de volume et une augmentation du temps de fermentation, ces conséquences sont dues à deux facteurs : la baisse de la production de CO2 (viabilité des levures) et la faible capacité de rétention de gaz du réseau gluténique. La perte de la qualité des pâtes congelées est accélérée durant le stockage. Cette thèse porte sur l’étude de l’effet de la congélation et de la conservation sur les levures et les propriétés techno-fonctionnelles des pâtes sucrées type Kougelhopf. Ce travail vise à l’étude de l’impact de la vitesse de congélation sur les propriétés microbiologiques, rhéologiques, structurales et sensorielles de ces pâtes. Elles ont été congelées à différentes températures (-20 °C, -30 °C, -40 °C et une immersion dans l'azote liquide) puis conservées à -40 °C pendant 9 semaines. Les principaux résultats de cette étude ont permis de mettre en évidence le rôle de la vitesse de congélation et de la durée de conservation sur les propriétés intrinsèques des pâtes sucrées surgelées. Il en découle que l’activité fermentaire et l’intégrité du réseau du gluten sont tributaire de la vitesse de congélation. En effet, cette dernière contrôle la taille et la localisation des cristaux de glace d’où la recherche d’un compromis entre une vitesse de congélation ni trop rapide pour diminuer la viabilité des levures ni trop lente pour former de gros cristaux pouvant perforer le réseau de gluten de la pâte. Ce travail a démontré que le surdosage de levure reste valable uniquement pour les pâtes sucrées surgelées destinées à être conservées au-delà de 4 semaines. Ce surdosage améliore ainsi la qualité globale du Kougelhopf en compensant la perte de l'activité des levures pendant la congélation et le stockage
The frozen doughs are relatively stable and can be manufactured on an industrial scale, distributed and baked on demand at the point of sale or consumption (Bake-off). Freezing sweet dough induces a decrease in specific volume and an increase in fermentation time, these effects are due to two factors: lower production of CO2 (yeast viability) and losing capacity to retain gas (gluten network integrity). The loss of quality of frozen dough is accelerated during storage. This study focuses on the freezing and frozen storage effects on Kougelhopf sweet doughs. The aim of this work is to study the impact of freezing rate on microbiological, rheological, structural, and sensory properties of sweet doughs. The sweet doughs were frozen at different temperatures (-20°C, -30°C, -40°C and an immersion in liquid nitrogen) and stored at -40°C for 9 weeks. The main results obtained showed an impact of freezing rate and frozen storage duration on the frozen doughs intrinsic properties. This study shown the dependence of fermentation activity and integrity of the gluten network with freezing rate, which controls size and location of ice crystals resulting in research of a compromise between freezing rate nor too fast to reduce yeast viability, nor too slow to form large ice crystals that could perforate gluten network. Added the yeast amount is necessary only for frozen sweet doughs to be stored beyond 4 weeks, which improves the overall quality of Kougelhopf by compensating for yeast activity decrease during freezing and frozen storage

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RUSCELLO, BRUNO. « Match analysis in team sports ». Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/898.

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La Match Analisi è argomento di discussione di grande interesse fra gli allenatori, i dirigenti sportivi e gli studiosi di scienze dello sport, e sta raggiungendo giorno per giorno una sempre maggiore rilevanza. Quando ci si riferisce a questo particolare aspetto della metodologia dell’allenamento sportivo, l’Informazione e l’elaborazione dei dati pertinenti devono essere considerati i fattori chiave. Attualmente il concetto di “Match Analisi” è usato in diversi paesi per definire il processo della osservazione e valutazione di un “insieme di comportamenti” adottati dagli atleti durante una partita o incontro, applicando diverse metodologie ed utilizzando specifici mezzi e strumenti, al fine di: 1. raccogliere ed elaborare i dati relativi ai diversi aspetti di un gioco o di alcune discipline sportive, sotto diversi punti di vista; 2. fornire le relative risultanze, opportunamente formattate, al fine di presentare i dati raccolti ed elaborati in un modo accessibile a tutti gli interessati, a diversi livelli (es. Allenatori, Atleti, studiosi di Scienze Motorie, Dirigenti, Giudici ed Arbitri, Giornalisti, ecc.); 3. fornire una interpretazione dei dati raccolti ed elaborati, al fine di definire meglio alcune caratteristiche specifiche della prestazione studiata (p.es. il dato fisiologico della prestazione o la biomeccanica o gli aspetti tattici di una partita o di un gioco) con il fine ultimo di migliorare questi aspetti attraverso la proposizione opportuna dei relativi processi di allenamento. Le finalità di questa tesi possono essere sintetizzate come segue: 1. fornire una panoramica a larga scala di quello che è il ruolo delle procedure di Match Analisi, inserite nel contesto generale della metodologia dell’allenamento sportivo; 2. analizzare il profilo professionale (Studio 1, Capitolo 11) richiesto per poter operare in questo campo specifico e gli atteggiamenti dei possibili Match Analisti, gli studenti di Scienze Motorie, attraverso un questionario appositamente progettato; 3. fornire un esempio di Analisi Biomeccanica Quantitativa, (Studio 2, Capitolo 7) studiando una specifica tecnica hockeistica, il “push”, utilizzato spesso durante una partita, al fine di affrontare efficacemente le cosiddette “Invarianti di Competizione” (Tiri Liberi, Corners, Rigori, ecc.); 4. condurre e presentare (Studio 3, Capitolo 7) una analisi estensiva delle capacità motorie e dei livelli di condizione fisica nelle hockeiste di elite (livello internazionale) e sub-elite (livello nazionale) al fine di definire i possibili indicatori fisiologici di prestazione (livello 1 della Match Analisi); 5. descrivere alcune procedure applicative di Match Analisi Qualitativa e Quantitativa (Hockey, Calcio; Studio 4 e 5, Capitoli 8 e 13), attraverso i processi di: · analisi dei software di Video Match Analisi disponibili sul mercato attualmente; · uso di un software commerciale di video match analisi per raccogliere dei dati a livello nazionale/internazionale in giochi sportivi come l’Hockey su prato ed il Calcio; · progetto di un nuovo software capace di aumentare l’efficienza del Data Base Video utilizzato; · analisi delle informazioni raccolte, attraverso un programma di Data Mining, al fine di trovare gli opportuni Predittori di Prestazione, capaci di ottimizzare i processi di allenamento e di aiutare in modo consistente il lavoro degli Allenatori, anche in situazioni di tempo reale. Sono proposte alcune considerazioni conclusive, che suggeriscono la necessità di maggiori ed ulteriori ricerche, per la maggior parte relative al terzo livello di analisi (la Strategia Generale e la Tattica). Un maggior coinvolgimento delle Università appare opportuno al fine di qualificare i futuri Match Analisti, assicurando loro le opportune conoscenze nei diversi ambiti disciplinari che possono concorrere a permettere un opportuno approccio interdisciplinare.
Match Analysis is a major subject among coaches, team managers and sport scientists and it is gaining an increasing relevance day by day. Information and the relevant data processing are the key factors while referring to this aspect of the sport training methodology. Currently the concept of “Match Analysis” is used in several countries to define the process of observing and evaluating a “whole of behaviours” performed by the players during a match, applying different methodologies and using specific instruments and tools,in order to: 1. collect and process the relevant data concerning the different features of games or athletic disciplines, under different points of view; 2. provide relevant presentations, appropriately formatted, in order to show the collected and processed data in an accessible way to all the concerned people, at different levels (i.e. coaches, players, sport scientists, officials, managers, journalists, etc.); 3. provide an interpretation of the collected and processed data, in order to define better some specific feature of the investigated performance (i.e. the physiological side of the performance or the biomechanics or the tactical features of a match or a game) with the ultimate aim of improving these aspects through the appropriate administration of the relevant training processes. The aims of the thesis may be summarized as follows: 1. providing a large-scale overview of what is currently the role of the Match Analysis procedures in the general context of the training methodology; 2. analysing the professional profile (Study 1, Chapter 11) required to operate in this specific field and the attitudes of the possible Match Analysts, the Sport Sciences students, through a questionnaire purposely designed; 3. providing an example of Quantitative Biomechanics Analysis, (Study 2, Chapter 7) investigating a specific hockey technical skill, (the “Push”) often performed during a match in order to cope efficiently with the “Competition Invariants” situations (Free Hits, Corners, Penalty Stroke, etc.); 4. in order to define the relevant physiological performance indicators (match analysis, level 1) in field hockey, an extensive analysis of the motor abilities and the fitness levels has been carried out and presented (Study 3, chapter 7) for elite (international level) and sub-elite (national level) women hockey players; 5. describing some applied Qualitative and Quantitative Match Analysis procedures (Field Hockey, Football; Study 4 and 5, Chapter 8 and 13), through the process of: · analysing the commercial Video Match Analysis software available on the market at date; · using a video match analysis commercial software to collect data at international/national level in team sports such as Field Hockey and Football; · designing a new software able to improve the efficiency of the used video data base; · analysing the collected information, by the means of Data Mining, in order to provide the relevant Performance Predictors, suitable to improve the training processes and to help consistently the work of coaches even in real-time situations. Some final considerations are provided, suggesting the need for more and further investigations for the most part of the third level of analysis (General Strategy and Tactic). A greater involvement of the Universities is needed in order to qualify the future Match Analysts, ensuring them the appropriate knowledge of several and different disciplines that combine a pertinent interdisciplinary approach.

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Gauthé, Mathieu. « Optimisation médico-économique des stratégies d'utilisation des examens TEP/TDM en imagerie oncologique ». Thesis, Université de Paris (2019-....), 2020. http://www.theses.fr/2020UNIP7040.

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Les machines de tomographie par émission de positons couplées à la tomodensitométrie (TEP/TDM) sont devenues incontournables en oncologie. De nombreuses études ont rapporté les performances des différents médicaments radiopharmaceutiques (MRP) utilisés en TEP/TDM dans de nombreux cancers. Pourtant, l’essor de la TEP/TDM reste régulièrement freiné en France pour des motifs économiques, alors que la différence entre le coût d’une TEP/TDM, comparé à celui d’une autre méthode d’imagerie utilisée en routine pour la même indication, n’est pas si évidente une fois qu’on considère l’impact sur la décision thérapeutique et les dépenses évitées par la révision de diagnostics erronés ou incomplets. Cependant, si tous les examens TEP/TDM sont actuellement remboursés de la même manière quel que soit le MRP utilisé, rendant ainsi leur coût identique de la perspective de l’assurance maladie, leurs coûts de production sont variables pour l’hôpital et constituent un paramètre à intégrer en relation avec la fréquence de l’indication de l’examen.Nous avons comparé plusieurs stratégies disponibles pour l’imagerie du cancer de la prostate en nous basant sur les données acquises pendant l’étude française multicentrique prospective FLUPROSTIC, qui incluait deux MRP pour l’imagerie TEP: la 18F-flurocholine (FCH) et le 18F-fluorure de sodium (FNa), la FCH étant 2 fois plus coûteuse pour l’hôpital que le FNa.L’analyse de l’impact de chaque stratégie d’imagerie sur la décision thérapeutique, basé l’analyse de questionnaires dédiés complétés par les cliniciens référents, a démontré que la TEP/TDM à la FCH était la modalité d’imagerie ayant le plus grand impact, en particulier pour les patients en situation de première récidive biologique.3La comparaison coût-utilité des stratégies d’imagerie, réalisée de la perspective de l’assurance maladie pour les patients en première récidive biologique de cancer de la prostate sur un horizon temporel « à vie », s’est basée sur un modèle combinant un arbre décisionnel intégrant les performances diagnostiques de l’imagerie et un modèle de Markov simulant l’histoire naturelle du cancer de la prostate. Cette analyse a démontré que la TEP/TDM à la FCH, modalité d’imagerie la plus exacte d’un point de vue diagnostique, avait une probabilité de 100% de chance d’être la stratégie la plus coût-utile pour des seuils de volonté à payer de 3000€ ou 9000€ par année de vie pondérée par la qualité gagnée, si l’interprétation de l’imagerie était faite par des médecins spécialistes locaux ou des experts respectivement. De la perspective de l’hôpital, la baisse de 20% du coût de la FCH entre 2018 et 2019 avait permis de rentabiliser la production d’examens TEP/TDM à la FCH fait pour l’imagerie du cancer de la prostate.La TEP/TDM augmente l’exactitude diagnostique et impacte sur la décision thérapeutique dans de nombreux cancers. Elle contribue à diminuer les traitements inutiles ainsi que les effets secondaires potentiels qui leur sont associés, à améliorer la qualité de vie des patients et à diminuer les coûts de prise en charge par le système de santé. L’évaluation médico-économique des MRP utilisés en imagerie TEP/TDM en oncologie semble donc indispensable, en plus de celle de leur performances diagnostiques, afin d’en optimiser l’utilisation. En France, cette évaluation devrait se faire des perspectives de l’assurance maladie et de l’hôpital, pour qui le coût de production d’un examen TEP/TDM peut varier sensiblement en fonction du coût du MRP et constituer un frein à son utilisation, même dans une indication fréquente pour laquelle les performances diagnostiques et l’impact sur la décision thérapeutique sont importants
Positron emission tomography coupled with computed tomography (PET/CT) devices are essential pathways in oncology. Many studies have reported the performances of the various radiopharmaceutical drugs (RPD) used for PET/CT imaging in many cancers. The rise of PET/CT remains slowed down in France for economic reasons. However, the difference between the cost of a PET/CT examination, compared to that of another modern imaging routinely used in the same indication, is not so obvious once considered the impact on decision making and the costs avoided by the revision of erroneous or incomplete diagnoses. Nonetheless, if all PET/CT examinations are currently reimbursed in the same way regardless of the RPD used, thus making their cost identical from the health insurance perspective, their production costs for the hospital vary and should be considered according to the frequency of the indication of the examination.We compared several imaging strategies for prostate cancer imaging by analyzing the data acquired during the French prospective multicenter FLUPROSTIC study, which included two RPD for PET imaging: 18F-flurocholine (FCH) and 18F-sodium fluoride (NaF), FCH being twice more costly for the hospital than NaF.The analysis of the impact of each imaging strategy on decision making, based on dedicated questionnaires completed by the referring clinicians, demonstrated that FCH PET/CT was the imaging modality that had the highest impact, especially for patients presenting with first biochemical recurrence.The cost-utility analysis, carried out from the health insurance perspective for patients with first biochemical recurrence of prostate cancer over a "lifetime" time horizon, was based on a model5combining a decision tree integrating the diagnostic performances of imaging and a Markov model simulating the natural history of prostate cancer. This analysis demonstrated that FCH PET/CT, the most accurate imaging modality from a diagnostic point of view, had a 100% probability of being the most cost-effective strategy for willingness to pay thresholds of 3,000€ or 9,000€ per quality-adjusted life year gained if the imaging reading was made by local specialists or experts respectively. From the hospital perspective, the 20% drop in the cost of FCH between 2018 and 2019 had made profitable the production of FCH PET/CT examinations for prostate cancer imaging.PET/CT increases diagnostic accuracy and has an impact on decision making in many cancers. It helps to reduce unnecessary treatments and their potential side effects, to improve the quality of life of patients and to reduce the treatment costs for the health care system. The medico-economic evaluation of RPDs used for PET/CT imaging in oncology, in addition to that of their diagnostic performances, seems essential in order to optimize their use. In France, this evaluation should be made from both perspectives of the health insurance and the hospital. Indeed, the PET/CT production costs can largely vary for the hospital according to the RPD costs and constitute a barrier to its use, even in a frequent indication for which diagnostic performances and impact on decision making are high

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Huang, Shan. « Nano-chemo-mechanics of advanced materials for hydrogen storage and lithium battery applications ». Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42710.

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Chemo-mechanics studies the material behavior and phenomena at the interface of mechanics and chemistry. Material failures due to coupled chemo-mechanical effects are serious roadblocks in the development of renewable energy technologies. Among the sources of renewable energies for the mass market, hydrogen and lithium-ion battery are promising candidates due to their high efficiency and easiness of conversion into other types of energy. However, hydrogen will degrade material mechanical properties and lithium insertion can cause electrode failures in battery owing to their high mobilities and strong chemo-mechanical coupling effects. These problems seriously prevent the large-scale applications of these renewable energy sources. In this thesis, the atomistic and continuum modeling are performed to study the chemical-mechanical failures. The objective is to understand the hydrogen embrittlement of grain boundary engineered metals and the lithium insertion-induced fracture in alloy electrodes for lithium-ion batteries. Hydrogen in metallic containment systems such as high-pressure vessels and pipelines causes the degradation of their mechanical properties that can result in sudden catastrophic fracture. A wide range of hydrogen embrittlement phenomena was attributed to the loss of cohesion of interfaces (between grains, inclusion and matrix, or phases) due to interstitially dissolved hydrogen. Our modeling and simulation of hydrogen embrittlement will address the question of why susceptibility to hydrogen embrittlement in metallic materials can be markedly reduced by grain boundary engineering. Implications of our results for efficient hydrogen storage and transport at high pressures are discussed. Silicon is one of the most promising anode materials for Li-ion batteries (LIB) because of the highest known theoretical charge capacity. However, Si anodes often suffer from pulverization and capacity fading. This is caused by the large volume changes of Si (~300%) upon Li insertion/extraction close to the theoretical charging/discharging limit. In particular, large incompatible deformation between areas of different Li contents tends to initiate fracture, leading to electro-chemical-mechanical failures of Si electrodes. In order to understand the chemo-mechanical mechanisms, we begin with the study of basic fracture modes in pure silicon, and then study the diffusion induced deformation and fracture in lithiated Si. Results have implications for increasing battery capacity and reliability. To improve mechanical stability of LIB anode, failure mechanisms of silicon and coated tin-oxide nanowires have been studied at continuum level. It's shown that anisotropic diffusivity and anisotropic deformation play vital roles in lithiation process. Our predictions of fracture initiation and evolution are verified by in situ experiment observations. Due to the mechanical confinement of the coating layers, our study demonstrates that it is possible to simultaneously control the electrochemical reaction rate and the mechanical strain of the electrode materials through carbon or aluminum coating, which opens new avenues of designing better lithium ion batteries. This thesis addresses the nano-chemo-mechanical failure problems in two green energy-carrier systems toward improving the performance of Li-ion battery anode and hydrogen storage system. It provides an atomistic and continuum modeling framework for the study of chemo-mechanics of advanced materials such as nano-structured metals and alloys. The results help understand the chemical effects of impurities on the mechanical properties of host materials with different metallic and covalent bonding characteristics.

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Weedon, Jennifer Louise. « Multidisciplinary team members' experiences of team formulation : a thematic analysis ». Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39887.

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Part 1: Literature Review - It is well-known that burnout is high in Community Mental Health Nurses. This has been associated with the workplace environment and tasks. Despite this, Community Mental Health Nurses are often based within multidisciplinary teams. In order to provide support for fellow team members, as well as offer an ‘alternative’ perspective, Clinical Psychologists have been offering ‘team formulation’. This is of particular interest within the clinical field of ‘psychosis’ where there continues to be uncertainty about using a diagnostic or formulation-based approach; it remains a highly contested area. Part 2: Research Report - The review of the literature aimed to examine quantitative studies and determine correlates and predictors of stress and burnout within Community Mental Health Nurses. Nine papers met the inclusion criteria, all of them cross-sectional studies. A narrative synthesis of the findings is presented using a framework of ‘individual’ and ‘situational’ factors. There was strong evidence to suggest that situational factors are highly associated with stress and burnout, however factors intrinsic to the individual were not routinely reported. Whilst burnout is operationalised within research by the use of a well-known measure, the relationship to other phenomena, such as stress and distress, is ill-defined. Part 3: Critical Appraisal - The research aim was to explore the experiences of multidisciplinary team members who have attended Team Formulation sessions within Early Intervention services. A thematic analysis was undertaken on the eleven interviews and three main themes were generated: team formulation offers a different perspective; the difference is valuable; and connection within the collective. These findings are considered within the evidence base for psychological formulation, as well as reflective practice and self-care. A reflective account of the research process is contained within the critical appraisal.

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ARMETTI, GIACOMO. « GEOMECHANICAL CHARACTERIZATION OF ROCK MASSES FOR TUNNEL EXCAVATION WITH TBM ». Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/612954.

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The prediction of Tunnel Boring Machine (TBM) performances and the comprehension of the relationship between the geological, mechanical and structural features of a rock mass and the machine behaviour are fundamental in order to select the most effective tunnel construction methods and to estimate the condition of excavation in terms of time and economic costs of the infrastructure. The general purpose of this work is to carry out predictive models utilisable during the early stage of tunnel planning and realisation; for this purpose, many approaches have been considered. Simple and multiple, both linear and nonlinear, regression analyses have been performed in order to achieve an empirical equation able to estimate the principal TBM performance indices (ROP and FPI). In addition, Multiple Correspondence Analysis and clustering have been developed. A modified version of the Rock Engineering System has been performed and used to obtain a predictive model. This study focuses on the exploratory tunnel named “La Maddalena”, located in Northern Italy, Western Alps, where geological surveys data have been continuously performed during tunnel construction; this allowed the collection of a large amount of geological, geotechnical and TBM performance data.

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Trent, Stoney. « Team cognition in intelligence analysis training ». The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1187034524.

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Awopone, Albert Kotawoke. « Optimising energy systems of Ghana for long-term scenarios ». Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/14752.

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This study explored energy solutions for Ghana by analysing alternative pathways from 2010 to 2040. The Long-range Energy Alternating Pathways (LEAP) tool was used the scenarios analysis. Four scenarios were developed based on key influencing factors identified in the literature. These are Base case, Coal, Modest Renewable Energy Technology (RET), and High RET scenarios. The Base case scenario was based on government-planned expansion and assumed no shift in policy. The Coal scenario assumed the same expansion trend as Base case with introduction of coal plants replacing a percentage of natural gas generation. Modest and High RET scenarios examined the development of the system with increased renewable energy integration. The results revealed that overall benefits are achieved with higher integration of renewable energy technologies. Economic benefits of 0.5 –13.23% is achieved in the RET scenarios depending on the cost development over the 30 year study period. The high RET offers the highest economic and environmental benefits. Subsequently, the optimal development of the system was examined using the LEAP/OSeMOSYS (Open Source Energy Modelling System) optimisation methodology. The least cost system developed by LEAP (Optimum scenario), was used as a reference to examine future possible energy policy direction in Ghana. The policy constraints analysed included emission targets, carbon taxes and transmission, distribution losses improvements and demand side efficiency. The results show that: suitable policies for clean power generation have an important role in CO2 mitigation in Ghana. The introduction of carbon minimisation policies will also promote diversification of the generation mix with higher penetration of renewable energy technologies. The study proposes promoting energy efficiency and improvement in transmission and distribution losses and utilisation of renewable energy as the best energy strategy for Ghana. Ghana needs ambitious targets, policies and implementation strategies to enhance energy efficiency, and decrease demand in the long term. Stable funding and promotion of transparent policies are required to promote high development of renewable energy technologies.

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Griffin, Jennifer. « An analysis of TEA domain proteins ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ43260.pdf.

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Trent, Stoney A. « Team cognition in intelligence analysis training ». Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1187034524.

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Thyer, Mark Andrew. « Modelling long-term persistence in hydrological time series ». Diss., 2000, 2000. http://www.newcastle.edu.au/services/library/adt/public/adt-NNCU20020531.035349/index.html.

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Tilley, Jason W. « A Comparison of Statistical Filtering Methods for Automatic Term Extraction for Domain Analysis ». Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/30818.

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Résumé :

Fourteen word frequency metrics were tested to evaluate their effectiveness in identifying vocabulary in a domain. Fifteen domain engineering projects were examined to measure how closely the vocabularies selected by the fourteen word frequency metrics were to the vocabularies produced by domain engineers. Six filtering mechanisms were also evaluated to measure their impact on selecting proper vocabulary terms. The results of the experiment show that stemming and stop word removal do improve overlap scores and that term frequency is a valuable contributor to overlap. Variations on term frequency are not always significant improvers of overlap.
Master of Science

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Becerril-Garcia, Hector Alejandro. « DNA-Templated Nanomaterials ». Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1823.pdf.

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Wright, Louwrance Peter. « Biochemical analysis for identification of quality in black tea (Camellia sinensis) ». Thesis, Pretoria : [s.n.], 2002. http://upetd.up.ac.za/thesis/available/etd-03012005-084935.

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Thèses sur le sujet « TEM ANALYSIS »

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