Tesis: "Tion in art"

1

Giedraitytė, Rūta. "„Epizodas. Siekis“. Stop kadrais animuota fotografija". Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110803_092305-37400.

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Šiame darbe analizuojami optinio meno, stop kadro animacijos veikimo principai, žmogaus gyvenimo momento svarba bei lentikuliarinės spaudos technologija, autorės nuomone, turintys sąsają su jos kurta animuota fotografija. Žmogaus trumpos nenutrūkstamo, ištisinio gyvenimo dalelės aktualumas kūrybiniame darbe virsta meniniu objektu, turinčiu aiškią motyvaciją, priežastis bei tikslus. Kūrybinio darbo dalyje pateikiama stop kadrais animuota fotografija. Darbas atspausdintas modernia technika, vienu iš naujausių spaudos būdų Lietuvoje – lentikuliarine spauda. Šis spaudos būdas atveria platesnes ir efektyvesnes galimybes, suteikiant darbui šiuolaikiškumo, išskirtinumo, originalumo bei skatina kurti naujas ir aktualias idėjas. Žiūrovui, stebinčiam animuotą fotografiją, suteikiama galimybė pristabdyti, sugrįžti atgal arba pakartoti reginį. Jis pats kontroliuoja žiūrėjimo kampą bei tempą, suvokdamas imituojamą judesį.
Here is analyzed optical art, stop-frame animation’s principle, the moment of importance in human life and lenticular press technology in this work. According to the author, all it has connection with her created work. The relevance of particles of human short-continuous life into the creative work becomes an artistic object with a clear motivation for the reasons and goals. Here is introduced stop motion animated photography in creative work park. The work is printed by modern technology, one of the newest ways to press in Lithuania - lenticular press. This printing method offers a wider and more effective option, giving modernity, exclusivity, originality for the work and encourages the development of new and relevant ideas. The viewer, who is observing an animated photography, has a opportunity to pause, go back or repeat the view. He controls the viewing angle and tempo, aware of the simulated motion.

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2

Kaplan, Randy Barbara. "The pre-leftist one-act dramas of Tian Han (1898-1968)". Connect to resource, 1986. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1227544118.

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3

Salisbury, Amelia Rose. "Hot cashew on a tin roof". Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4743.

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4

Gekosky, Sandra J. "Luca Della Robbia and his Tin-Glazed Terracotta Sculptures". Ohio University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1126821886.

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5

Antonio, Jennifer. "The creative use of the tin-containing layer on float glass". Thesis, University of Sunderland, 2009. http://sure.sunderland.ac.uk/6490/.

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This research explored the creative potential of the phenomenon of “bloom”, a matt film caused by the expansion of the tin-containing layer on the surface of float glass that occurs when it is reheated to temperatures above 600° C. “Bloom” has long been regarded as a problem, both in industry and by artists using float glass for kilnforming. Under specific conditions designed to stretch the glass the expansion of the tin-containing layer can be controlled sufficiently to produce a new surface effect similar to iridescence, instead of a matt film. The research examined ways of using the new surface to create images in glass. In addition, the hardness of the tin in relation to the glass causes the images to form slight low relief. The visual effects can be contrasted with those of existing methods of creating surfaces on glass and with methods of forming low relief in glass, in being lightreflecting and integral to the medium itself. While the effects are quite subtle, methods derived from creative practice were developed to create artworks that exploited their unique visual characteristics. These are composed of imagery, glass and light. The research has been approached from the perspective of an artist working with the medium of glass. Its purpose was to explain and control the effects sufficiently in order to use them for creative expression. The submission consists of a body of artwork and a written thesis.

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6

Shlasko, Ellen. "Delftware Chronology: A New Approach to Dating English Tin-Glazed Ceramics". W&M ScholarWorks, 1989. https://scholarworks.wm.edu/etd/1539625501.

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7

Giguère, Amélie. "Art contemporain et documentation : la muséalisation d'un corpus de pièces éphémères de type performance". Thèse, Université d'Avignon, 2012. http://www.archipel.uqam.ca/4942/1/D2362.pdf.

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Quarante années après la parution de l'article de Lucy R. Lippard et de John Chandler, publié dans Art International, la notion de « dématérialisation » apparaît toujours dans les discours sur l'art contemporain. Elle désigne une tendance à l'œuvre dans la création artistique qui dévalorise la matérialité de l'objet, ses qualités plastiques associées à un savoir-faire technique, de même que son caractère unique et permanent. En outre, la dématérialisation de l'art peut être interprétée comme une critique de l'institution muséale et, les propositions artistiques qui répondent à ses préceptes, comme des pièces qui « résistent » à la muséalisation. Affirmant que la muséalisation est l'ensemble des activités de sélection, de documentation et de présentation publique qui octroient, à une proposition artistique, un statut muséal ou qui transforment cette proposition en un objet qui témoigne d'une réalité donnée, comment dès lors des propositions qui n'ont pas de matérialité persistante intègrent-elles les collections muséales? Comment les informations colligées, organisées et enregistrées autour de ces pièces assurent-elles une connaissance juste de celles-ci? En somme, par quelles stratégies, artistes ou professionnels, opèrent-ils la muséalisation de ces pièces contemporaines et, en particulier, des pièces éphémères de type performance? En interrogeant d'un côté la production d'un art contemporain qui remet en question l'objet traditionnel comme finalité du projet artistique et, en questionnant de l'autre les activités muséales traditionnelles et contemporaines, le « document » s'impose comme notion clé pour éclairer la question de la muséalisation de cet art contemporain. Une hypothèse de travail est formulée : certaines propositions contemporaines ne se présentent pas sous la forme d'un objet déterminé qui en constitue le terme, mais plutôt sous la forme d'un ensemble de documents. Cet ensemble de documents constitue ce que nous appelons la « face documentaire » de la proposition artistique. En transposant la notion de paratexte de Gérard Genette aux objets de cette analyse, il est dit que la « face documentaire » a pour fonction principale de présenter, ou de rendre présentes, les propositions artistiques, de réconcilier leurs différents modes d'existence et d'assurer leur muséalisation le plus conformément possible aux intentions des créateurs. C'est à la lumière des sciences de l'information et de la communication, en particulier des travaux de Jean Meyriat et de ceux des chercheurs réunis sous le pseudonyme Roger T. Pédauque, qu'est définie la notion de « document », opératoire dans le concept de « face documentaire ». Une étude de cas est menée. Le corpus est composé de sept pièces éphémères de type performance et de leurs objets associés qui appartiennent à des collections muséales ou à des Fonds régionaux d'art contemporain, en France ou au Canada. L'entretien auprès des professionnels des musées, des artistes et de leurs représentants, de même que la consultation et l'analyse de sources primaires et secondaires, comme les fiches descriptives, les dossiers d'œuvres et les revues spécialisées et les catalogues, constituent les principales méthodes d'enquête. L'analyse procède par l'identification et la mise en évidence, par le récit, des différents destinateurs, formes, fonctions et statuts des documents qui composent la « face documentaire » des propositions choisies. Sont ainsi interrogées, pour chacune des pièces, la création ou la sélection de documents et leur entrée dans une collection muséale. Sont ensuite questionnées la documentation muséale de ces pièces et enfin, leur présentation publique. L'étude des cas permet de dégager deux stratégies principales de muséalisation : la muséalisation articulée autour d'un prolongement matériel qui tend à faire œuvre et la muséalisation articulée autour d'un projet de réitération. Dans les premiers cas, la muséalisation s'accomplit par la sélection et la désignation d'une pièce ou d'un ensemble de pièces et de documents de différents statuts, prédéterminés et identifiés ou non par l'artiste comme celui ou ceux qui tient ou tiennent lieu de la performance. Dans les seconds cas, la muséalisation s'opère par l'obtention d'un droit de réitération, par la sélection et la désignation d'un ensemble de pièces ou de documents de différents statuts, ainsi que par la production ou la reconnaissance d'un « script » de la performance qui vise essentiellement à guider la reprise correcte de la proposition éphémère. L'étude de cas permet en outre de mettre en évidence trois stratégies de présentation publique des « performances muséalisées », soit l'exposition d'un objet ou de plusieurs objets en situation de rencontre, l'exposition documentaire et enfin, la réitération de la performance. Enfin, la recherche montre que la muséalisation de pièces éphémères de type performance redéfinit les activités muséales de la sélection, de la documentation et de la présentation. Elle interroge l'objet de musée comme élément pivot de ces activités. Elle montre aussi qu'une attention plus grande est portée aux productions paratextuelles de ces travaux artistiques, c'est-à-dire à la « face documentaire » de ces derniers ou à la documentation comprise dans une acception élargie. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : art contemporain, document, documentation, exposition, muséalisation, performance, réitération, Guy de Cointet, Esther Ferrer, Claudie Gagnon, Yves Klein, Gina Pane, Tino Sehgal, Françoise Sullivan.

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8

Nibhanupudi, Syam S. "Affect of pressurised solidification on the secondary dentritic arm spacing in lead-tin alloy". abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1453603.

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9

Dowling, Andrew John y andrewjohn3055@yahoo com. "Novel strategies for surface micromachining TiN thin films deposited by filtered arc". Swinburne University of Technology. Industrial Research Institute Swinburne, 2005. http://adt.lib.swin.edu.au./public/adt-VSWT20051129.085933.

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TiN is used commercially as a wear resistant coating on cutting tools and as a diffusion barrier in microelectronics. TiN has gained increased interest as a material for MEMS, however there has been very little work carried out in the area of patterning and releasing TiN for use as a structural MEMS material. This thesis presents an investigation into the patterning and release of filtered arc deposited TiN thin films using surface micromachining techniques. Two novel strategies are presented for patterning TiN thin films and are achieved using excimer laser micromachining and photolithographic wet-etching. TiN was deposited onto single crystal Si and Cr and Cu sacrificial layers on Si. The use of Cr as a sacrificial layer was found to facilitate the best quality patterning of the TiN and hence the majority of the work involved using Cr sacrificial layers. TiN was deposited using partial filtration and full filtration and differences in the ability to selectively laser pattern the TiN from the Cr sacrificial layer are presented. Various analytical techniques were employed to investigate the origin of the difference in laser patterning the TiN thin films. The establishment of TiN and Cr as a novel material combination for surface micromachined MEMS was extended by etching the Cr sacrificial layer to facilitate the release of TiN stress-measurement structures. The major finding of this thesis is that filtered arc deposited TiN thin film on Cr can be used as a material combination to surface micromachine freestanding TiN structures as high quality patterning and etch selectivity can be achieved using both excimer laser micromachining and photolithographic wet-etching.

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10

Mühlbacher, Marlene. "High-resolution characterization of TiN diffusion barrier layers". Licentiate thesis, Linköpings universitet, Tunnfilmsfysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-120394.

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Titanium nitride (TiN) films are widely applied as diffusion barrier layers in microelectronic devices. The continued miniaturization of such devices not only poses new challenges to material systems design, but also puts high demands on characterization techniques. To gain understanding of diffusion processes that can eventually lead to failure of the barrier layer and thus of the whole device, it is essential to develop routines to chemically and structurally investigate these layers down to the atomic scale. In the present study, model TiN diffusion barriers with a Cu overlayer acting as the diffusion source were grown by reactive magnetron sputtering on MgO(001) and thermally oxidized Si(001) substrates. Cross-sectional transmission electron microscopy (XTEM) of the pristine samples revealed epitaxial, single-crystalline growth of TiN on MgO(001), while the polycrystalline TiN grown on Si(001) exhibited a [001]-oriented columnar microstructure. Various annealing treatments were carried out to induce diffusion of Cu into the TiN layer. Subsequently, XTEM images were recorded with a high-angle annular dark field detector, which provides strong elemental contrast, to illuminate the correlation between the structure and the barrier efficiency of the single- and polycrystalline TiN layers. Particular regions of interest were investigated more closely by energy dispersive X-ray (EDX) mapping. These investigations are completed by atom probe tomography (APT) studies, which provide a three-dimensional insight into the elemental distribution at the near-interface region with atomic chemical resolution and high sensitivity. In case of the single-crystalline barrier, a uniform Cu-enriched diffusion layer of 12 nm could be detected at the interface after an annealing treatment at 1000 °C for 12 h. This excellent barrier performance can be attributed to the lack of fast diffusion paths such as grain boundaries. Moreover, density-functional theory calculations predict a stoichiometry-dependent atomic diffusion mechanism of Cu in bulk TiN, with Cu diffusing on the N-sublattice for the experimental N/Ti ratio. In comparison, the polycrystalline TiN layers exhibited grain boundaries reaching from the Cu-TiN interface to the substrate, thus providing direct diffusion paths for Cu. However, the microstructure of these columnar layers was still dense without open porosity or voids, so that the onset of grain boundary diffusion could only be found after annealing at 900 °C for 1 h. The present study shows how to combine two high resolution state-of-the-art methods, TEM and APT, to characterize model TiN diffusion barriers. It is shown how to correlate the microstructure with the performance of the barrier layer by two-dimensional EDX mapping and three-dimensional APT. Highly effective Cu-diffusion barrier function is thus demonstrated for single-crystal TiN(001) (up to 1000 °C) and dense polycrystalline TiN (900 °C).

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11

Kim, George E. (George Ea-Hwan). "The effects of low pressure nitrogen on titanium cathode sources in TiN arc ion-plating". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29062.

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The arc ion-plating technique is used in the industrial coating processes where TiN thin films are deposited onto various base materials. The overall objective of this research was to study the effects of low pressure nitrogen introduced into a continuous, titanium vacuum arc. An arc ion-plating system was designed and built to allow for as much flexibility as possible. Permanent magnets were placed behind the cathode surface to confine and rotate the arc.
Changes in cathode, arc and emission properties were noted with respect to vacuum, argon and nitrogen ambients. The introduction of nitrogen, above a critical pressure ($ sim$1 $ times 10 sp{-3}$ Torr), increased arc velocity and decreased crater diameter, erosion rate and ion emission. This occurred when arc rotation was combined with nitrogen introduction. Thermal properties of the cathode during arcing seemed to play an important role in determining the extent of nitrogen-cathode interaction. X-ray photoelectron spectroscopy (XPS) analysis has shown that nitriding occurred within the regions of arcing and was dependent on nitrogen pressure (with all other parameters remaining constant). The most encouraging result found was the complete elimination or macroparticles normally present in the coating/film.

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12

Cheung, Shin-yee. "A study of the tomb murals depicting the ascent to paradise during the Wei, Jin, Northern-and-Southern dynasties Wei Jin Nan bei chao "sheng tian tu" yan jiu /". Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B38301362.

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13

Worthington, James R., Paul Kapp, Vladislav Minaev, James B. Chapman, Frank K. Mazdab, Mihai N. Ducea, Ilhomjon Oimahmadov y Mustafo Gadoev. "Birth, life, and demise of the Andean-syn-collisional Gissar arc: Late Paleozoic tectono-magmatic-metamorphic evolution of the southwestern Tian Shan, Tajikistan". AMER GEOPHYSICAL UNION, 2017. http://hdl.handle.net/10150/626289.

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The amalgamation of the Central Asian Orogenic Belt in the southwestern Tian Shan in Tajikistan is represented by tectono-magmatic-metamorphic processes that accompanied late Paleozoic ocean closure and collision between the Karakum-Tarim and Kazakh-Kyrgyz terranes. Integrated U-Pb geochronology, thermobarometry, pseudosection modeling, and Hf geochemistry constrain the timing and petro-tectonic nature of these processes. The Gissar batholith and the Garm massif represent an eastward, along-strike increase in paleodepth from upper-batholith (similar to 21-7km) to arc-root (similar to 36-19km) levels of the Andean-syn-collisional Gissar arc, which developed from similar to 323-288Ma in two stages: (i) Andean, I-type granitoid magmatism from similar to 323-306Ma due to northward subduction of the Gissar back-arc ocean basin under the Gissar microcontinent, which was immediately followed by (ii) syn-collisional, I-S-type granitoid magmatism in the Gissar batholith and the Garm massif from similar to 304-288Ma due to northward subduction/underthrusting of Karakum marginal-continental crust under the Gissar microcontinent. A rapid isotopic pull-up from similar to 288-286Ma signals the onset of juvenile, alkaline-syenitic, post-collisional magmatism by similar to 280Ma, which was driven by delamination of the Gissar arclogite root and consequent convective asthenospheric upwelling. Whereas M-HT/LP prograde metamorphism in the Garm massif (650-750 degrees C/6-7kbar) from similar to 310-288Ma was associated with subduction-magma inundation and crustal thickening, HT/LP heating and decompression to peak-metamorphic temperatures (similar to 800-820 degrees C/6-4kbar) at similar to 2886Ma was driven by the transmission of a post-collisional, mantle-derived heat wave through the Garm-massif crust.

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14

Godward, Julie. "Paper plate masks and tin can totem poles: A documentary analysis of Ontario elementary school visual arts curriculum and support documents form 1985 to 1998 for representations of a multicultural perspective". Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27632.

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This documentary analysis study critically examines representations of a multicultural perspective in selected Ontario elementary school visual arts curriculum and support documents. The study focuses on five documents that were published between 1985 and 1998, a period that coincides with important curricular changes in art education. This period was also significant with regards to developments that occurred in this province relating to multicultural education. To complete this analysis, references to race, ethnicity and culture were examined in order to identify ways in which they were being utilized in the documents. Furthermore, these references were analyzed from the perspective of critical multiculturalism to determine how multicultural education was being represented in the resources. I argue that while certain efforts were made to include a multicultural perspective in art education during this time period, these were for the most part inadequate in that they tend to present information out of context, fail to include diverse perspectives, overemphasize certain groups to the detriment of others, and perpetuate false information and stereotypes. I also contend that these deficiencies in art education are closely related to the political context that influenced the role and place of art education within the educational system.

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15

Jacques, Clarisse Callegari. "As pessoas e as coisas : an?lise espacial em dois s?tios arqueol?gicos, Santo Ant?nio da Patrulha, RS". Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2007. http://tede2.pucrs.br/tede2/handle/tede/2392.

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Made available in DSpace on 2015-04-14T13:47:30Z (GMT). No. of bitstreams: 1 386309.pdf: 2282764 bytes, checksum: 42ee66ce9d47a65c2e7720078b396ea7 (MD5) Previous issue date: 2007-01-08
O objetivo desta disserta??o ? entender alguns significados das rela??es humanas com a cultura material, a partir do estudo pontual de uma parcela de dois s?tios arqueol?gicos. Estes est?o localizados no Vale do Rio dos Sinos, RS, munic?pio de Santo Ant?nio da Patrulha e a cultura material neles identificada foi associada ? subtradi??o arqueol?gica Guarani. A abordagem usada considera que os artefatos passam por contextos de cria??o, comunica??o e consumo. Foram estudadas nesta pesquisa t?cnicas de lascamento e de manufatura da cer?mica, gestos criativos e o consumo de artefatos, juntamente com a sua localiza??o espacial nas ?reas trabalhadas em cada s?tio. Os artefatos foram, assim, pensados como tendo uma rela??o ativa com as pessoas e como sendo carregados de significados. Acredita-se, assim, estar contribuindo para o entendimento da ocupa??o dos grupos humanos associados a esta subtradi??o arqueol?gica no Rio Grande do Sul, Brasil.

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16

Pons, Frédéric. "Electrical contact material arc erosion: experiments and modeling towards the design of an AgCdO substitute". Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33816.

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AgCdO is one of the most widely used contact materials in the world because of its outstanding performance. Nevertheless, due to environmental considerations, it will soon be completely forbidden by European environmental directives. Therefore, finding a good substitute is of crucial importance. Electrical arc erosion plays a crucial role in the reliability and life of power switching devices. Depending on the contact material's behavior in response to an electrical arc, surface damage can induce severe changes in contact material properties that will impact the power switching device's functioning. Consequently, electrical arc effects and consequences on the contact material surface are of first importance. In this context, we have focused our research activities on the following axes. First of all, in order to better understand AgCdO (Current contact material in aerospace industry) and AgSnO₂(Potential candidate to AgCdO substitution) arc erosion behaviors, arc erosion experiments, where the power switching devices have been subjected to different numbers of arc discharges, have been realized. Further, a general macroscopic electrical contact arc erosion model valid for low and high currents was developed. To compare model results to experimental data, this model describes the complete breaking process of electrical contacts and gives the total amount of material removed after one breaking operation. In parallel, arc erosion experiments on AgCdO power switching devices have been conducted at high currents (0 -> 1000 A) in order to validate the arc erosion model. Next, using the general arc erosion model, the properties having the greatest influence on the electrical arc erosion process have been determined through simulations on silver contact material. At this stage, ab initio calculations were needed to obtain ranges of variation of certain silver contact material properties. Finally, an investigation of the trends of changing local contact material on these identified material properties was performed. This study composition of AgSnO₂was based on ab initio calculations for two different oxide compositions of AgSnO₂. These will allow us to give directions to aid the design of a good substitute for AgCdO, and therefore, to complete the main objective of this research work.

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17

Wik, Linnea. "Betraktarens rum : En komparativ utställningsanalys av Hilma afKlints verk De tio största genom två olika rumsligheter". Thesis, Södertörns högskola, Konstvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-44298.

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The spatiality of a viewer. A comparative exhibition analysis of Hilma af Klint's work The ten largestthrough two different spatialities.I have studied a viewer’s encounter with Hilma af Klint’s work The ten largest through two differentspatialities, the exhibition room at Moderna Museet Malmö and Moderna Museet Malmös Instagramaccount. With my research, I have wanted to get an insight into how a digital room such as an Instagramaccount can function as an exhibition room for art in a time when more and more is digitalized, whichescalated during the year when physical experiences were limited due to a global pandemic. Through acomparative exhibition analysis of the two different spaces and with the help of phenomenological theoryprimarily based on Maurice Merleau-Ponty further developed by Bia Mankell and phenomenologicaltheory in the digital based on Emmanuel Alloa, the Instagram account has been set in relation to theexhibition room at the museum. This comparative analysis showed that the two spatialities as exhibitionroom for the same work is both two separated exhibitions with characteristics influenced by space theyare shown through but also as two inevitably intertwined exhibitions and spaces influenced by each otherand each other's characteristics.
Populärvetenskaplig sammanfattningI den här uppsatsen har jag undersökt en betraktares möte med Hilma af Klints verk De tio största genomtvå olika rumsligheter, visningsrummet på Moderna Museet Malmö samt Moderna Museet Malmösinstagramkonto. Jag har med min undersökning velat få en inblick i hur ett digitalt rum så som ettinstagramkonto kan fungera så ett visningsrum för konst i en tid då mer och mer digitaliseras, vilket underåret eskalerat då fysiska upplevelser begränsats på grund av en global pandemi. Genom en komparativutställningsanalys av de två olika rumsligheterna och med hjälp av fenomenologisk teori framföralltutifrån Maurice Merleau-Ponty vidareutvecklad av Bia Mankell och fenomenologisk teori i det digitalautifrån Emmanuel Alloa har instagramkontot satts i relation till visningsrummet på museet. Dennakomparativa analys ledde fram till en syn på de två rumsligheterna för samma verk både som två separatautställningar med egenskaper påverkade av det rum de visas genom men även som två oundvikligensammanflätade utställningar och rum påverkade av varandra och varandras egenskaper.

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18

Léaustic, Anne. "Nouveaux colloïdes photosensibles à base d'oxyde de titane TiO". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37607106d.

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19

Poata-Smith, E. S. Te Ahu y n/a. "The political economy of Maori protest politics, 1968-1995 : a Marxist analysis of the roots of Maori oppression and the politics of resistance". University of Otago. Department of Political Studies, 2002. http://adt.otago.ac.nz./public/adt-NZDU20070508.153703.

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This thesis provides a Marxist analysis of the political economy of contemporary Maori protest politics in the years from 1968 to 1995. It is argued that Maori protest politics embraces a range of competing political ideologies, which are informed by different assumptions about the causes of Maori inequality in wider society, and in turn, different sets of strategies for ameliorating and transcending that inequality. Overall, the thesis has two central concerns: firstly, it identifies the critical economic, political and ideological conditions and context that have allowed particular competing political ideologies and strategies to dominate contemporary Maori protest politics. This involves a particular focus on understanding and explaining the rise of identity politics and cultural nationalism as the dominant political strategy within Maori protest politics. This involves a particular focus on understanding and explaining the rise of identity politics and cultural nationalism as the dominant political strategy within Maori protest politics. Secondly, the thesis critically assesses the effectiveness of contemporary Maori struggles against racism and oppression on the basis of whether they involve, or are likely to contribute towards, the transformation of the generative structures that give rise to manifest inequalities between Maori and non-Maori. It is argued that the systematic alienation of land and the inequality that exists between Maori and non-Maori are not simply the result of the underlying cultural values of individual non-Maori but are rather the result of the historical process of capitalist development in Aotearoa and the economic, political and ideological requirements necessary for the generalised commodification of indigenous labour-power. The thesis explores how the politics and practice of Maori protest has been shaped and influenced to a large extent by the underlying social, economic, political and ideological forces of global capitalism. It is argued that the international collapse of the long boom, the global upturn in class struggle and the emergence of the New Left internationally from the late 1960s had an enormous influence on the political direction of Maori protest in the New Zealand context. The success of the working class offensive and the growing political influence of rank and file Maori workers ensured that Maori protest groups formed part of the progressive social movements of the time. Indeed, although some were explicitly nationalist in their orientation, these movements were consciously part of the Left. The balance of political forces within the Maori protest movement changed considerably during the late 1970s and early 1980s with the rise of the New Right as a political force internationally together with the rise of employer militancy, the defeat and demoralization of the working class movement internationally, the decline of the social movements and the absence of mass struggle. This had important implications for the influence of the various ideological factions that co-existed uneasily in the Maori political milieu from the early 1970s onwards. The downturn in militant mass struggle saw the rise in the influence of identity politics as cultural nationalist strategies came to dominate Maori protest politics, representing a fundamental retreat from Left-wing ideas. In practice this entailed a rejection of the class politics and mass struggle that had informed the politics and strategies of Maori protest groups from the late 1960s, and its replacement with a politics of cross-class alliances and a personal rejection of �Pakeha society�. In practice this was a recipe for passivity and divisiveness within the Maori protest movement itself. The politics of cultural nationalism left Maori ill-equipped to resist the ruling class counter-offensive and the anti-working class policies that successive governments introduced to restore the conditions for profitable capital accumulation. In particular, the rejection of a class analysis of Maori inequality in capitalist society has undermined the capacity of working class Maori to resist the neo-liberal agenda and a Treaty of Waitangi settlement process that has resulted in a substantial shift in resources to those sections of Maori society already wealthy and powerful. Although the settlement process represented an important concession by the state, it has never compensated for the anti-working class policies of governments since 1984, which have widened the social and economic inequalities in New Zealand society. In this way, the emphasis on cultural identity alone as the determining factor in Maori oppression has been counter-productive for working class Maori as successive governments shifted the costs of the economic crisis on to the weakest sections of the community. As New Zealand entered a new period of economic and social crisis in the 1990s, the commercial interests of Maori tribal executives, Maori corporate enterprises, and the Maori bureaucracy were clearly at odds with the material interests of the vast majority of working class Maori families. This fundamental conflict in class interests was to set the scene for a revival of militancy on scale not seen since the 1970s.

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20

Bisinella, Carolina Aveline Deitos Rosa. "Por uma arqueologia fenomenol?gica : experi?ncias m?ltiplas em um lugar (s?tio Ari Duarte I, Pinhal da Serra/RS)". Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2012. http://tede2.pucrs.br/tede2/handle/tede/2417.

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This thesis is the result of my own personal questionings, doubts and reflections on Archaeology, focusing mainly on its practice. Based on the assumption that Archaeology is a science of the past, developed in the present, and projected for the future, I have developed a micro-scale study around the archaeological site Ari Duarte I (RS-PE-41) where I have tried to emphasize the practices, experiences personal and otherwise which occurred there to individuals and/or groups of individuals over time. From a phenomenological point of view, based on perceptive and corporal engagement to the material world, I have analyzed the active involvement of not only those who lived a long time ago, but also of people such as the archaeologists themselves and the inhabitants of Pinhal da Serra, such as farmers, students and political authorities, among others. Conceptualizing that location as a place, constituted by meaning, I have organized this text in order to approach large thematic axes linked to it: the discovery, the relation to the land, to the things and their substances and to the heritage
Esta tese ? fruto de questionamentos, d?vidas e reflex?es pessoais minhas a respeito da arqueologia, principalmente em rela??o ? sua pr?tica. Partindo do pressuposto de que se trata de uma ci?ncia do passado, desenvolvida no presente e projetada para o futuro, desenvolvi um estudo em micro escala, em torno do s?tio arqueol?gico Ari Duarte I (RS-PE-41), procurando privilegiar as pr?ticas, as experi?ncias e as viv?ncias ocorridas nele por diversos indiv?duos e/ou grupos ao longo do tempo. Sob uma ?tica fenomenol?gica, baseada no engajamento perceptivo e corporal com o mundo material, analisei o envolvimento ativo n?o apenas daqueles que viveram l? muito tempo atr?s, mas igualmente de pessoas como os pr?prios arque?logos e os habitantes de Pinhal da Serra, tais como agricultores, estudantes e autoridades pol?ticas, dentre outros. Conceituando este local enquanto um lugar, constitu?do de significados, organizei o texto a fim de abordar grandes eixos tem?ticos a ele vinculados: a descoberta, a rela??o com a terra, com as coisas e suas subst?ncias e com o patrim?nio

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21

Doeuff, Sylvie. "Elaboration de TIO par voie sol-gel du précurseur au matériau /". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376133004.

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22

Fourgeaud, Nicolas. "La performance au miroir des médiations. Enjeux théoriques et critiques". Thesis, Paris 3, 2012. http://www.theses.fr/2012PA030057.

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À l’orée des années soixante, la performance a cherché à imposer un art de l’action éphémère que n’entraverait aucun type de médiation, qu’il soit symbolique (la distance acteur/spectateur), technique (les médias), ou même linguistique (le langage, les signes). Enjeu de nombreux débats entre les années 1960 et 1990, ces tentatives ont trouvé de multiples formulations théoriques s’appuyant sur les outils du poststructuralisme en particulier, mais aussi sur des cadres de pensée différents, directement hérités du modernisme de Greenberg. On explore ici les étapes et enjeux de ce croisement, jusqu’à la rupture apportée dans les années 1990 et 2000 où les débats théoriques, toujours dirigés par des schémas poststructuralistes, redonnèrent une place centrale aux médiations, tout particulièrement au document. Or, la figure importante de la pratique artistique qu’est devenu le document depuis les années soixante s’avère mettre en question l’ontologie traditionnelle de la performance, orientée sur l’événement, autant que son épistémologie, qui valorise l’expérience directe. La prise en compte des dimensions instrumentales et artistiques du document nous conduit à réviser la poïétique traditionnelle de la performance et les théories de la communication qui lui sont liées, et à repenser par là même l’opposition entre objet et événement qui fonde la définition de la performance. C’est ainsi qu’on interroge le rapport de celle-ci à l’inscription, pour la redéfinir comme un art irréductible à son contexte d’exécution et travaillé en profondeur par la reproduction et la représentation, au travers notamment de l’étude de certaines figures exemplaires, Allan Kaprow, Chris Burden ou Tino Sehgal
On the edge of the 1960’s, performance looked after imposing an art of ephemeral action that no kind of mediation would impede, be it symbolic (the distance between actor and spectator), technical (the medias), or even linguistical (language, signs). Those attempts led to numerous discussions between the 1960’s and the 1990’s, and have found numerous theoretical formulations using particularly the tools of poststructuralism, but also frames of thought directly inherited from Greenberg modernism. We explore here the stages and issues of this cross-over until the break of the 1990’s and 2000’s where the theoretical debates, always using poststructuralist schemes, gave a central role to mediations, particularly to the document. Documents have become an important figure of artistic practice since the 1960’s and turned out to question the traditional ontology of performance, based on the event, as well as its epistemology that promotes live experience. We try to consider the instrumental and artistic dimensions of the document ; this leads us to revise the traditional poetics of performance and theories of communication that are related to it, and to consider anew the opposition between object and event on which the definition of performance is based. Thus, we question the links between performance and inscription, redefined as an art that is irreducible to its context of execution and worked in depth by reproduction and representation, through the study of certain figureheads : Allan Kaprow, Chris Burden or Tino Sehgal

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23

Thomas, Jean-Charles. "Cinématique tertiaire et rotations de blocs dans l'ouest de l'Asie centrale : Tien Shan Kirghiz et dépression Tadjik /". Rennes : Université de Rennes I, Géosciences, 1994. http://catalogue.bnf.fr/ark:/12148/cb35695687q.

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24

Jiang, Dianlu y n/a. "Studies of Photocatalytic Processes at Nanoporous TiO2 Film Electrodes by Photoelectrochemical Techniques and Development of a Novel Methodology for Rapid Determination of Chemical Oxygen Demand". Griffith University. School of Environmental and Applied Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040723.155003.

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In this work, a series of simple, rapid and effective photoelectrochemical methodologies have been developed and successfully applied to the study of kinetic and thermodynamic characteristics of photocatalytic oxidation processes at TiO2 nanoparticulate films. As an application of the systematic studies of photocatalytic processes by photoelectrochemical techniques, a rapid, direct, absolute, environmental-friendly and accurate COD analysis method was successfully developed. In this work, the TiO2 nanoparticles colloid was prepared by the sol-gel method. The TiO2 nanoparticles were immobilized onto ITO conducting glass slides by dip-coating method. Thermal treatment was carried out to obtain nanoporous TiO2 films of different structures. At low calcination temperature (below 600°C), nanoporous TiO2 films of pure anatase phase were prepared. At high calcination temperature (above 600°C), nanoporous TiO2 films of mixed anatase and rutile phases were obtained. At these film electrodes, the work was carried out. By employing steady state photocurrent method and choosing phthalic acid as the model compound, the photocatalytic activity of the TiO2 nanoporous films calcined at various temperatures and for different lengths of time was evaluated. It was found that the films with mixed anatase and rutile phases calcined at high temperature exhibited high photocatalytic activity. Based on semiconductor band theory, a model was proposed, which explained well this finding. By employing linear sweep voltammetry (under illumination) and choosing glucose (an effective photohole scavenger) as a model compound, the characteristics of the photocatalytic processes at nanoparticulate semiconductor electrodes were investigated. Characteristics of the nanoporous semiconductor electrodes markedly different from bulk semiconductor electrodes were observed. That is, within a large range of electrode potentials above the flat band potential the electrodes behaved as a pure resistance instead of exhibiting variable resistance expected for bulk semiconductor electrodes. The magnitude of the resistance was dependent on the properties of the electrodes and the maximum photocatalytic oxidation rate at TiO2 surface determined by the light intensity and substrate concentration. A model was proposed, which explained well the special characteristics of particulate semiconductor electrodes (nanoporous semiconductor electrodes). This is the first clear description of the overall photocatalytic process at nanoparticulate semiconductor electrodes. The investigation set a theoretical foundation for employing photoelectrochemical techniques to study photocatalytic processes. By using the transient technique (illumination step method analogous to potential step method in conventional electrochemistry), the adsorption of a number of strong adsorbates on both low temperature and high temperature calcined TiO2 nanoporous films was investigated. Similar adsorption characteristics for different adsorbates on different films were observed. In all the cases, three different surface bound complexes were identified, which was attributed to the heterogeneity of TiO2 surface. The photocatalytic degradation kinetics of the pre-adsorbed organic compounds of different chemical nature was also studied by processing the photocurrent-time profiles. Two different photocatalytic processes, exhibiting different rate characteristics, were observed. This was, again, attributed to the heterogeneity of the TiO2 surface corresponding to heterogeneous adsorption characteristics. The catalytic first order rate constants of both fast and slow processes were obtained for different organic compounds. It was found that for different adsorbates of different chemical nature the magnitudes of rate constant for the slow kinetic process were very similar, while the magnitudes of rate constant for the fast process were significantly affected by the photohole demand characteristics of different adsorbates. Photohole demand distribution that depends on the size and structure of the adsorbed molecules was believed to be responsible for the difference. By employing steady state photocurrent method, the photocatalytic degradation kinetic characteristics of both strong adsorbates and weak adsorbates of different chemical structures were compared at pure anatase TiO2 nanoporous TiO2 films as well as at anatase/rutile mixed phase TiO2 nanoporous film electrodes. At the former electrodes for all the different organic compounds studied, the photocatalytic reaction rate increased linearly with concentration at low concentrations. Under such conditions, it was demonstrated that the overall photocatalytic process was controlled by diffusion and was independent of the chemical nature of organic compounds. However, the linear concentration range and the maximum photocatalytic reaction rate at high concentrations were significantly dependent on the chemical nature of the substrates. This was explained by the difference in the interaction of different organic compounds with TiO2 surface, the difference in their photohole demand distributions at the TiO2 surface and the difference in their nature of intermediates formed during their photocatalytic mineralization. In contrast, at the latter electrodes for the photocatalytic oxidation of different organic compounds the linear ranges (diffusion control concentration range) and the maximum reaction rates at high concentration were much larger than at the former electrodes and much less dependent on the chemical nature of the organic compounds. The spatial separation of photoelectrons and photoholes (due to the coexistence of rutile phase and anatase phase) and the increase in the lifetime of photoelectrons and photoholes are responsible for the excellent photocatalytic activity of the electrodes. By employing the thin-layer photoelectrochemical technique (analogous to the thin-layer exhaustive electrolytic technique), the photocatalytic oxidation of different organic compounds at the mixed phase TiO2 nanoporous electrodes were investigated in a thin layer photoelectrochemical cell. It was found that the charge derived from exhaustive oxidation agreed well with theoretical charge expected for the mineralisation of a specific organic compound. This finding was true for all the compounds investigated and was also true for mixtures of different organic compounds. The photocatalytic degradation kinetics of different organic compounds of different chemical identities in the thin layer cell was also investigated by the photoelectrochemical method. Two kinetic processes of different decay time constants were identified, which were attributed to the degradation of preadsorbed compounds and the degradation of compounds in solution. For the degradation of compounds in solution, a change in the overall control step from substrate diffusion to heterogeneous surface reaction was observed. For different organic compounds, the variation of the rate constant was determined by the photohole demand rather than by the chemical identities of substrates. The kinetics of the fast kinetic process, on the other hand, was greatly affected by the adsorption properties of the substrates. For the strong adsorbates, the rate was much larger than for weak adsorbates. However, the rate constant of the process was independent of the chemical identities of the substrates and the variation of the constant was also determined by the photohole demand. Based on the principles of exhaustive photoelectrocatalytic degradation of organic matter in a thin layer cell, a novel, rapid, direct, environmental-friendly and absolute COD analysis method was developed. The method was tested on synthetic samples as well as real wastewater samples from a variety of industries. For synthetic samples with given compositions the COD values measured by my method agree very well with theoretical COD value. For real samples and synthetic samples the COD values measured by my method correlated very well with those measured by standard dichromate COD analysis method.

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25

Linderoth, Jenny. "Hilma af Klints De tio största : En fenomenologisk-hermeneutisk studie av ett verk som tycks vara drömlikt och förmedlar glädje". Thesis, Högskolan i Gävle, Avdelningen för humaniora, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36670.

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Detta arbete undersöker hur tio målningar från 1907 fungerar som bärare av ett andligt budskap. Verket, som är en del av ett större, heter De tio största och är utfört genom Hilma af Klint på uppdrag av Högre väsen som hon sa sig vara i kontakt med. Hilma af Klint var en svensk konstnär som levde 1862–1944. I undersökningen har en grupp på tio personer i åldrarna 19 till 24 år, en åldersgrupp som kallas generation Z eller zoomers, reflekterat över dessa element och verkets helhet. Analysen visar att gruppen får en gemensam upplevelse av budskap som kan kopplas till det konstnären formulerat i sina anteckningar och att det framkommer ytterligare ett resultat som matchar det syfte som återfinns i anteckningar från seanser 2 år innan verket påbörjas. Svaren från de tio informanterna är analyserade genom en fenomenologisk-hermeneutisk tolkningsmetod där den fenomenologiska delen samverkar med hermeneutiken för att fånga informanternas upplevelse av Hilma af Klints verk. Genom fenomenologins fokus på hur en grupp uppfattar och upplever och sedan drar slutsatser från detta ges en djupare inblick i något som tillsynes kan tyckas vara dolt.

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26

Idrissi, Kandri Noureddine. "Elaboration et caractérisation d'une membrane minérale conductrice à base d'un mélange d'oxydes TiO-RuO". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37606071b.

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Che, Hui. "Surface Chemistry and Work Function of Irradiated and Nanoscale Thin Films Covered Indium Tin Oxides". Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157651/.

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In this study, we used UV-ozone Ar sputtering, X-ray photoelectron and ultra-violet photoelectron spectroscopies and sputtering based depositions of RuO2 and Se nano-layers on indium tin oxides (ITOs). We elucidated the effect of Ar sputtering on the composition and chemistry of Sn rich ITO surface. We demonstrated that while a combination of UV-ozone radiation and Ar sputtering removes most of the hydrocarbons responsible for degrading the work function of ITO, it also removes significant amount of the segregated SN at the ITO surface that's responsible for its reasonable work function of 4.7eV. We also demonstrated for the first time that sputtering cleaning ITO surface leads to the reduction of the charge state of Sn from Sn4+ to Sn2+ that adds to the degradation of the work function. For the nano-layers coverage of ITO studies, we evaluated both RuO2 and Se. For RuO2 coated ITO, XPS showed the formation of a Ru-Sn-O ternary oxide. The RuO2 nano-layer reduced the oxidation state of Sn in the Sn-rich surface of ITO from +4 to +2. The best work function obtained for this system is 4.98eV, raising the effective work function of ITO by more than 0.5 eV. For the Se coated ITO studies, a systematic study of the dependence of the effective work function on the thickness of Se overage and its chemistry at the Se/ITO interface was undertaken. XPS showed that Se reacts with Sn at the Sn-rich surface of ITO determined the presence of both negative and positive oxidation state of Se at the Se/ITO interface. The Se also reduced the oxidation state of Sn from Sn4+ to Sn2+ in the Sn-rich ITO surface. The highest effective work function obtained for this system is 5.06eV. A combination of RuO2/Se nanoscale coating of optimally cleaned ITO would be a good alternative for device applications that would provide work function tuning in addition to their potential ability to act as interface stabilizers and a barrier to reaction and inter-diffusion at ITO/active layers interfaces responsible for long term stability of devices and especially organic solar cells and organic light emitting diodes.

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28

Jimenez, Villarin Javier. "Assessing the degradation and transformation of emerging pollutants submitted to TiO2 photocatalysis by high-resolution mass spectrometry techniques. Are we posing a new hazard to the environment?" Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/404561.

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In the past 50 years there has been increasing interest and concern over pharmaceutical drugs and their presence in the environment, since they and/or their metabolites could induce toxicological effects and bacterial resistance in living organisms. Conventional sewage treatment plants are not able to efficiently remove these chemicals, reason why these compounds are being introduced into the aquatic environment at concentration levels of parts per-billion (ppb) and parts per-trillion (ppt). Although these concentrations are much lower than those used in medical applications, the related potential toxic effects are still poorly known and cannot be discarded. Heterogeneous TiO2 photocatalysis is an advanced oxidation process that can achieve complete oxidation and mineralisation of such organic compounds. TiO2 nanoparticles and nanofibers have been extensively investigated as the suspended semiconductors in common heterogeneous photocatalysis set-ups. However, the complete recovery of the semiconductor is still a major industrial challenge. That is the reason why their fixation onto an inner support represents a great alternative to overcome this problem. The present PhD thesis has studied the degradation of four pharmaceutical drugs (ofloxacin, clofibric acid, diclofenac and ibuprofen) using two different set-ups (suspended and supported conditions) with three different TiO2 catalysts: synthesised TiO2 nanofibers and P25 nanoparticles and commercially available nanofibers, used as reference materials. Prior performing the photocatalytical process, all TiO2 samples were submitted to physical characterisation (BET surface area, X-Ray diffraction and SEM microscopy) showing significant differences between the synthesised and reference materials. Prepared TiO2 nanofibers, however, appeared to be the material with maximum adsorption capacity (derived from Langmuir’s isotherm) and appeared to be slightly better at degrading the pharmaceuticals under study at a concentration of 10 µg L-1. Nevertheless, when the experiments were conducted under real conditions, none of all the studied catalysts could effectively degrade the studied compounds. Additionally, this work has studied how one of the selected pharmaceuticals (ofloxacin) was degraded along the photocatalytical process by mass spectrometry techniques: (tandem) high-resolution mass spectrometry and ion mobility mass spectrometry. Due to the vast amount of information generated by these cutting-edge instruments, different data treatment techniques were applied in order to achieve a fast identification of the generated transformation products (TPs). The degradation of ofloxacin led to the formation of 59 TPs. Chemical structures of these TPs were hypothesised on the basis of their accurate mass and product ion spectra. However, due to the lack of standards of these TPs, these hypothesised structures could not be confirmed until ion mobility, in combination with theoretical calculations, was used. This technique not only rendered additional separation in the gas phase for some of the identified TPs but also provided a tool to support the complete elucidation of the chemical structures hypothesised. Having detected and identified ofloxacin TPs, the investigation of this PhD thesis was centred on the study of their toxicological impact. Toxicity was assessed by two different end-points: luminescence, using the luminescent bacteria Vibrio-fischeri and cytotoxicity using three different human cell lines (HK-2, HepG2 and fibroblast cells). Both end-points clearly demonstrated that, even at low concentrations, the formation of these TPs led to a toxicity increase when compared to the parent drug ofloxacin. Even though this toxicity increase, complete detoxification was achieved by ensuring enough irradiation time and promoting the complete depletion of ofloxacin TPs. The individual toxicity of these TPs was then studied by fractionating the reaction crude with a semi- preparative HPLC column which restricted the number of toxic TPs. Due to the poor chromatographic resolution achieved, the chemical synthesis of the generated TPs seems to be the only option, to date, to study their individual toxicity.
A lo largo de los últimos 50 años ha habido un creciente interés acerca de los fármacos y/o sus metabolitos ya que su presencia en el medio ambiente podría inducir efectos toxicológicos adversos y/o resistencia bacteriana. Puesto que los sistemas de depuradoras de aguas son incapaces de eliminarlos, éstos son introducidos y detectados en el sistema acuático. Aunque los niveles encontrados son mucho menores que las usadas en medicina, sus efectos adversos no pueden ser descartados. La fotocatálisis heterogénea mediante TiO2 es un proceso de oxidación avanzado que puede conseguir la completa oxidación y mineralización de estos compuestos en el agua. La presente tesis doctoral se ha centrado en la degradación de cuatro fármacos (ofloxacino, ácido clofíbrico, diclofenaco e ibuprofeno) con tres catalizadores de TiO2: nanofibras sintetizadas y materiales comerciales: en forma de nanopartícula y nanofibra. Las nanofibras preparadas mostraron una mayor capacidad de adsorción y degradación de los fármacos estudiados. A pesar de los buenos resultados obtenidos experimentando en agua sintética, todos los catalizadores bajaron su rendimiento al experimentar con matriz de agua real. Adicionalmente, se estudió cómo el ofloxacino se degradaba y transformaba a lo largo del proceso fotocatalítico mediante espectrometría de masas de alta resolución y de movilidad iónica. Se detectaron e identificaron 59 productos de transformación, los cuales fueron adicionalmente estudiados mediante la técnica de movilidad iónica acompañada de cálculos teóricos. Esta última combinación no solo demostró su poder separativo sino que proporcionó una herramienta para la confirmación de las estructuras químicas propuestas. Finalmente, se estudió la toxicidad asociada a los productos de transformación del ofloxacino, evaluada mediante dos targets: luminiscencia (Vibrio-fischeri) y citotoxicidad (células humanas). Ambos ensayos demostraron que la generación de estos productos de degradación incrementaba toxicidad. Aun así, la completa detoxificación se consiguió extendiendo el tiempo de fotocatálisis. A fin de estudiar su toxicidad individual, el crudo de reacción fue fraccionado mediante HPLC semipreparativo. Sin embargo, la baja resolución cromatográfica obtenida imposibilitó el estudio individual y limitó a una fracción este aumento de la toxicidad. Actualmente, la síntesis química, parece la única vía para posibilitar el estudio individual de los productos generados.

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Cardot, Francis. "Etude de l'insertion de l'hydrogène dans le dioxyde de titane par la mesure de l'impédance de l'interface TiO2/électrolyte aqueux". Grenoble : ANRT, 1989. http://catalogue.bnf.fr/ark:/12148/cb37593851w.

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Ango, Jean-Paul. "Electrooxydation du D-Sorbitol sur électrodes métalliques (Pt, Au) : comparaison avec la photooxydation aux interfaces semi-conducteur (TiO(2) / électrolyte". Poitiers, 1989. http://www.theses.fr/1989POIT2261.

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Sutherland, Brad Alexander y n/a. "Heme oxygenase and the use of tin protoporphyrin in hypoxia-ischaemia-induced brain damage : mechanisms of action". University of Otago. Department of Pharmacology & Toxicology, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090119.150318.

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Stroke is the third largest cause of death, and the leading cause of disability worldwide. Treatments are sought to reduce mortality, and increase survival time following an ischaemic stroke. Hypoxia-ischaemia (HI) is the combination of cerebral ischaemia and global hypoxia that can lead to neuronal damage, particularly perinatally. The complex neurodegenerative cascade following ischaemic stroke and HI activates many stress pathways, including heme oxygenase (HO). HO metabolises free heme to release iron, carbon monoxide, and biliverdin, which is subsequently metabolised to bilirubin. This thesis aims to elucidate the role HO plays following HI, and assess any neuroprotective mechanisms using HO modulators. The 26 day old rat model of HI was used to induce the neurodegenerative cascade. All animals were sacrificed 3 days post-insult. Immunohistochemistry and Western blotting demonstrated that HO-1 was increased in the ipsilateral hemisphere of both HI (by 1.7 � 0.1 fold: p = 0.016, n = 4) and middle cerebral artery occlusion (MCAO) brains (by 1.6 � 0.1 fold: p = 0.037, n = 4), compared to controls. HO-2 was constitutively expressed throughout the control brain, but HI upregulated HO-2 expression (by 1.7 � 0.2 fold: p = 0.027, n = 4) ipsilaterally, whereas MCAO did not alter HO-2 expression. Administration of the HO inhibitor tin protoporphyrin (SnPP; 30[mu]mol/kg intraperitoneally) daily, beginning 1 day prior to HI until sacrifice, reduced infarct volume to 50% � 10 of saline-treated animals (p = 0.039, n = 6-8). The HO inducer ferriprotoporphyrin (FePP; 30[mu]mol/kg) had no effect on infarct volume. HO activity and protein expression were not significantly altered following treatment with SnPP. Therefore, the neuroprotective actions of SnPP may be through alternative mechanisms. SnPP treatment increased HI + saline-induced total nitric oxide synthase (NOS) activity by 1.5 � 0.06 fold (p < 0.001, n = 6-8). Conversely, SnPP inhibited both inducible NOS (50% � 7 of HI + saline; p = 0.045, n = 7-8) and cyclooxygenase (COX) activity (32% � 6 of HI + saline; p = 0.049, n = 4-8). SnPP treatment also increased mitochondrial complex I activity by 1.6 � 0.25 fold (p = 0.04, n = 4-8) and complex V activity by 1.7 � 0.26 fold (p = 0.046, n = 4-8) in the ipsilateral hemisphere. It appears that SnPP is acting on inflammatory and mitochondrial enzymes to produce neuroprotection. In vitro analysis of cultured RAW264.7 macrophages exposed to lipopolysaccharide (LPS; 10[mu]g/mL) treated with SnPP (dose range: 10⁻�⁰M - 10⁻⁵M) did not alter nitrite levels or cell viability. However, high dose SnPP (10⁻⁵M) in the absence of LPS increased nitrite levels from control cells by 2.7 � 0.7 fold (p = 0.043, n = 6), complementing the in vivo total NOS data. Other mechanisms such as NMDA receptor activation were not affected by 100[mu]M SnPP or 100[mu]M SnCl₂ in patch clamped cortical pyramidal neurons. Overall, the role that HO plays following HI remains unclear, but this thesis provides definitive evidence that SnPP (an established HO inhibitor) provides neuroprotection. This neuroprotection may be due to its effects on inducible pathways such as NOS and COX. Therefore, further experimentation is required to fully elucidate the role that HO plays following cerebral ischaemia, and additional in vivo evidence will be necessary to establish HO inhibitors as a putative candidate for cerebral ischaemia neuroprotection.

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32

Bensitel, Mohammed. "Caractérisation et étude de la sulfatation de trois oxydes métalliques ZrO, TiO et Mgo par spectroscopie infrarouge". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37611819f.

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33

Davis, Griffith M. "Exposure to Nanomaterials Results in Alterations of Inflammatory and Atherosclerotic Signaling Pathways in the Coronary Vasculature of Wildtype Rodents". Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248468/.

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Cardiovascular disease (CVD) is the leading cause of death for people of most ethnicities on a global scale, and countless research efforts on the pathology of CVD has been well-characterized over the years. However, advancement in modern technologies, such as nanotechnology, has generated environmental and occupational health concerns within the scientific community. Current investigation of nanotoxicity calls into question the negative effects nanomaterials may invoke from their environmental, commercial, and therapeutic usage. As a result, further research is needed to investigate and characterize the toxicological implications associated with nanomaterial-exposure and CVD. We investigated the toxicity of multi-walled carbon nanotubes (MWCNT) and titanium dioxide (TiO2), which are two prominently used nanomaterials that have been previously linked to upregulation of inflammatory and atherogenic factors. However, the mechanistic pathways involved in these nanomaterials mediating detrimental effects on the heart and/or coronary vasculature have not yet been fully determined. Thus, we utilized two different routes of exposure in rodent models to assess alterations in proinflammatory and proatherogenic signaling pathways, which are represented in contrast throughout the dissertation. In our MWCNT study, we used C57Bl/6 mice exposed to MWCNTs (1 mg/m3) or filtered air (FA-Controls), via inhalation, for 6 hr/d for 14d. Conversely, intravenous TiO2 was administered to F344 male fisher rats, following 24h and 28d post-exposure to a single injection of TiO2-NPs (1 mg/kg), compared to control animals. MWCNT-exposed endpoints investigated the alterations in cholesterol transport, such as lectin-like oxidized low-density lipoprotein receptor (LOX)-1 and ATP-binding cassette transporter (ABCA)-1, inflammatory markers [tumor necrosis factor (TNF)-α], interleukin (IL)-1β/IL-6, nuclear-factor kappa-light-chain-enhancer of activated B cells (NF-κB) and signaling factors involved in activation of the pathway, as well as intracellular/vascular adhesion molecule(s) (VCAM-1, ICAM-1), and miRNAs (miR-221/-21/-1), associated with CVD, were analyzed in cardiac tissue and coronary vasculature. Cardiac fibrotic deposition, matrix-metalloproteinases (MMP)-2/9, and reactive oxygen species (ROS) were also assessed. TiO2-exposure endpoints also involved alterations on cholesterol transport proteins via LOX-1 and ABCA-1, factors of inflammation, namely intracellular macrophages and interleukin (IL)-1β, MMP-2/9 activity and protein expression, fibrotic deposition, and ROS generation were analyzed via quantitative detection or histologically in both cardiac tissue and coronary vasculature. Results from both studies found alterations in fibrotic deposition, upregulation in LOX-1 expression and MMP-2/9 activity, and ROS generation; with a concurrent decrease in ABCA-1 expression in cardiac tissue and coronary vasculature. Individually, MWCNT-exposed endpoints had shown induction of cardiac TNF-α, MMP-9, IκB Kinase (IKK)-α/β, and miR-221 mRNAs; as well as increased coronary expression of TNF-α and VCAM-1. TiO2 studies found increases in IL-1β and MMP-9 protein expression, as well as intracellular macrophage induction. Both studies also found, through pre-treatment of NADPH oxidase inhibitor, apocynin, resulted in attenuation of nanomaterial-exposure mediated ROS production; with nitric oxide synthase inhibitor, L-NNA, also showing attenuation, but only in our MWCNT-exposed inhalation study. The results from both studies have demonstrated, through different routes of administration, exposures, and rodent models; that exposure to nanomaterials can mediate signaling pathways involved in initiation and/or progression of CVD.

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34

Barth, Wolfgang H. "Geology of the Cleveland tin mine, Tasmania, Australia, with special reference to mineral chemistry and rare earth distribution /". Heidelberg : Mineralogisch-Petrographischen Instituts der Universität Heidelberg, 1986. http://catalogue.bnf.fr/ark:/12148/cb37428675x.

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35

Gao, Yang 1966. "Solderability Study of Tin/Lead Alloy Under Steam-Aging Treatment by Electrochemical Reduction Analysis and Wetting Balance Tests". Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc501051/.

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Two types of solder samples, pins and through-holes were tested by SERA™ (Sequential Electrochemical Reduction Analysis) and Wetting Balance after various length of steamaging treatment. It was shown that after steam-aging, both types of specimen gave a similar electrochemical reduction curve, and solderabilty predictions made from SERA™ test agree with results obtained from Wetting Balance test on a qualitative base. Wetting balance test of pin samples after SERA™ test confirmed that SERA™ is a non-destructive testing method -- it even restored solderability. Comparison of electrochemical reduction behavior of samples under different treatment indicates that steam-aging can not reproduce exactly the effect of naturally atmospheric aging, and may not be the best artificial accelerating environment adopted.

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36

Barral, Gérard. "Etude électrochimique de films pyrolytiques de RuO2 et/ou TiO2 sur titane dans le domaine de tension correspondant à la stabilité de l'eau". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376115931.

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37

Benhenda, Slimane. "Etude, par microscopie électronique et par spectrométrie Auger, de revêtements protecteurs du cuivre (Au, Ni, Au/Ni et TiN)". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376028362.

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38

Fabre, Jean-Paul. "Elaboration et caractérisation de nouvelles membranes minérales d'ultrafiltration en TiO et en ZrO réalisées par les techniques "sol-gel"". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376048712.

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39

d'Arles, Césaire. "Tien preken van Caesarius van Arles (470-542) : vertaald en toegelicht : een onderzoek naar de invloed van Augustinus in de prediking van Caesarius van Arles /". Schiedam : [s.n.], 1996. http://catalogue.bnf.fr/ark:/12148/cb39133157c.

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Proefschrift--Faculteit der Godgeleerdheid--Leiden--Rijksuniversiteit, 1996.
Mention parallèle de titre ou de responsabilité : Dix sermons de Césaire d'Arles, traduits et expliqués, avec un résumé français. Bibliogr. p. I-XIV.

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40

Rimal, Sirish. "Characterization of Post-Plasma Etch Residues and Plasma Induced Damage Evaluation on Patterned Porous Low-K Dielectrics Using MIR-IR Spectroscopy". Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849694/.

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As the miniaturization of functional devices in integrated circuit (IC) continues to scale down to sub-nanometer size, the process complexity increases and makes materials characterization difficult. One of our research effort demonstrates the development and application of novel Multiple Internal Reflection Infrared Spectroscopy (MIR-IR) as a sensitive (sub-5 nm) metrology tool to provide precise chemical bonding information that can effectively guide through the development of more efficient process control. In this work, we investigated the chemical bonding structure of thin fluorocarbon polymer films deposited on low-k dielectric nanostructures, using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Complemented by functional group specific chemical derivatization reactions, fluorocarbon film was established to contain fluorinated alkenes and carbonyl moieties embedded in a highly cross-linked, branched fluorocarbon structure and a model bonding structure was proposed for the first time. In addition, plasma induced damage to high aspect ratio trench low-k structures especially on the trench sidewalls was evaluated both qualitatively and quantitatively. Damage from different plasma processing was correlated with Si-OH formation and breakage of Si-CH3 bonds with increase in C=O functionality. In another endeavor, TiN hard mask defect formation after fluorocarbon plasma etch was characterized and investigated. Finding suggest the presence of water soluble amines that could possibly trigger the formation of TiN surface defect. An effective post etch treatment (PET) methods were applied for etch residue defect removal/suppression.

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41

Fechete, Alexandru Constantin y e54372@ems rmit edu au. "Layered Surface Acoustic Wave Based Gas Sensors Utilising Nanostructured Indium Oxide Thin Layer". RMIT University. Electrical and Computer Engineering, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091105.141111.

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Planar two-dimensional (2-D) nanostructured indium oxide (InOx) and one-dimensional (1-D) tin oxide (SnO2) semiconductor metal-oxide layers have been utilised for gas sensing applications. Novel layered Surface Acoustic Wave (SAW) based sensors were developed consisting of InOx/SiOxNy/36°YXLiTaO3, InOx/SiNx/SiO2/36°YXLiTaO3 and InOx/SiNx/36°YXLiTaO3 The 1 µm intermediate layers of silicon oxynitride (SiOxNy), silicon nitride (SiNx) and SiO2/SiNx matrix were deposited on lithium tantalate (36°YXLiTaO3) substrates by r.f. magnetron sputtering, electron-beam evaporation and plasma enhanced chemical vapour deposition (PECVD) techniques, respectively. As a gas sensitive layer, a 100 nm thin layer of InOx was deposited on the intermediate layers by r.f. magnetron sputtering. The targeted gases were ozone (O3) and hydrogen (H2). An intermediate layer has multiple functions: protective role for the interdigital transducers' electrodes as well as an isolating effect from InOx sensing layer, thereby improving the sensor performance. The developed SAW sensors' exhibited high response magnitudes with repeatable, reversible and stable responses towards O3 and H2. They are capable of sensing concentrations as low as 20 parts-per-billion for O3 and 600 parts-per-million for H2. Additionally a conductometric type novel sensing structure of SnO2/36°YX LiTaO3 was also developed by depositing a thin layer of SnO2 nanorods by PECVD. The gas sensing performance exhibited repeatable, reversible, stable responses towards NO2 and CO. The surface morphology, crystalline structure and preferred orientation of the deposited layers were investigated by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). A polycrystalline, oxygen deficient non-stoichiometric InOx with grain sizes of 20-40 nm was revealed. The 1-D nanostructures were characterised by Transmission Electron Microscopy (TEM) showing nanorods with needle-like shape , diameters of 10-20 nm a t the top and 30-40 nm at the base as well as a preferential growth orientation of [ ] on the LiTaO3 substrate. The developed sensors are promising for O3, H2 and CO sensing.

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42

Eddajibi, Abdel Hamid. "Recherche des paramètres physico-chimiques qui déterminent la stabilité des suspensions aqueuses des poudres de BaCO3 et de TIO2 en vue de la réalisation de leur mélange". Grenoble : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb375937659.

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43

Merideth, Craig. "An archaeometallurgical survey for ancient tin mines and smelting sites in Spain and Portugal : Mid-Central Western Iberian geographical region, 1990-1995 /". Oxford : BAR, 1998. http://catalogue.bnf.fr/ark:/12148/cb37032249b.

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44

Métreau, Laetitia. "La " faïence " dans les pavements médiévaux en France (XIIIe-XIVe s.) : approche technique, stylistique et symbolique du cas de Suscinio (c. 1330-1350)". Thesis, Bordeaux 3, 2012. http://www.theses.fr/2012BOR30036.

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De son apparition dans les cours raffinées du lointain Orient islamisé à son exploitation industrielle en Occident, les procédés d’élaboration et les usages de la faïence ont évolué. En France, en l’état actuel des connaissances, l’introduction de cette technique remonte à l’époque gothique. Elle se manifeste alors de manière simultanée, dans des zones géographiques spécifiques, ponctuellement utilisée dans la composition de quelques luxueux pavements, où elle coexiste fréquemment avec des carreaux de terre cuite à glaçure transparente de tradition indigène. De tels pavements, parce qu’ils témoignent de la rencontre entre deux traditions techniques et culturelles, apparaissent comme des objets d’étude privilégiés pour appréhender conjointement les questions relatives à l’origine, la production et la consommation que pose la « faïence » à ses débuts en France. À partir de l’approche globale du cas de Suscinio, choisi en raison de son exemplarité, les chemins que cette technique exogène a empruntés et les raisons de son utilisation ont pu être précisés. Les données techniques, iconographiques et analytiques collectées grâce à la démarche méthodologique proposée apportent de nouveaux éléments de réponse. Ainsi, l’importation de produits finis et l’expérimentation locale ont pu être exclues au profit de l’importation de savoirs techniques ou du transfert de connaissances. Le répertoire iconographique et le style de tradition gothique ont montré qu’il y avait eu adaptation de la technique à un nouveau milieu socio-culturel. Son utilisation dans des lieux de l’édifice particuliers et particulièrement importants ne servait pas seulement une démonstration de pouvoir mais lui conférait également le statut de marqueur spatial, hiérarchique et social
Tin-glazed earthenware manufacturing and use changed from its beginnings in the refined courts of the Islamic Far East up to its manufacturing in the West. In France, the technique was introduced during the Gothic period. It appears simultaneously, in specific geographical areas, at times used in the composition of luxurious floor-tiles where it often coexists with indigenous transparent high-lead glazed tiles. Such floor-tiles bear witness to the meeting between two technical and cultural traditions. That is the reason why they are particularly appropriate when studying together issues relating to the geographical origin, production and consumption of tin-glazed earthenware technique at its beginnings in France. The ways followed by this exogenous technique and the reasons for its use were clarified through the overall approach of the exemplary case of Suscinio. Technical, iconographical and analytical data collected by using a multidisciplinary methodology have provided some answers. Imported products and local experimentation can be excluded in favor of imported skills or transfer of knowledge. The Gothic tradition of the iconography and the style showed that the technique was adapted to a new socio-cultural context. Its use in particular and particularly important places was not only reserved to a manifestation of power but also worked as spatial, hierarchical and social markers

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45

Potin, Annick. "Etude par microscopique électronique STEM des joints de grains dans les céramiques électroniques application au cas des variations à base de ZnO et des diélectriques Ba TiO-LiF /". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb376004908.

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46

Júnior, Adonias Ribeiro Franco. "Obtenção de revestimentos dúplex por nitretação a plasma e PVD-TiN em aços ferramenta AISI D2 e AISI H13". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-02102003-114623/.

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No presente trabalho foi avaliado o efeito da microestrutura e da capacidade de suportar carregamento de camadas nitretadas produzidas em aços ferramenta AISI H13 e AISI D2 sobre a aderência e a resistência ao desgaste microabrasivo de revestimentos de TiN-PVD. Em cada um desses aços, foram produzidas camadas nitretadas de diferentes estruturas e espessuras, e foram determinadas experimentalmente as curvas potencial início de formação de camada branca, para a nitretação a 520oC. Para o aço ferramenta AISI H13, o emprego de tempos de pré-tratamento de nitretação mais prolongados ( aproximadamente 11 h) foi necessário para aprofundar a camada nitretada e, conseqüentemente, aumentar a capacidade de suportar carregamento dos revestimentos, evitando a formação de bordas que provocam o lascamento e a escamação das camadas de TiN. Observou-se que esse tipo de falha persiste se a zona de endurecimento for pouco profunda, uma vez que a transição de propriedades mecânicas da camada de TiN para o núcleo não nitretado continua abrupta e a capacidade de suportar carregamento da camada nitretada ainda é baixa. Por outro lado, curtos tempos de nitretação (aproximadamente 42 min.) foram suficientes para aumentar a aderência das camadas de TiN ao aço ferramenta D2, pois o núcleo não nitretado desse aço possui uma capacidade de suportar carregamento razoável. Observou-se que a resistência ao desgaste microabrasivo e a aderência dos revestimentos são prejudicadas com a presença de uma camada preta na interface camada de TiN/camada nitretada. Quando a superfície dos revestimentos é carregada, falhas do tipo casca de ovo facilmente ocorrem.
In this work, the influence of both the microstructure and the load-bearing capacity of nitrided layers, formed on top of AISI D2 and AISI H13 tool steels, on adhesion and wear resistance of PVD-TiN coatings was studied. The threshold nitriding potential curves for the above mentioned steels and the optimum conditions of the pre-treatments which increased the adhesion as well as the wear resistance of the PVD-TiN were determined experimentally. By using longer nitriding times (about 11 h) and lower nitrogen contents in the gas mixture (about N2-5%vol.), it was possible to minimize the pile-up degree of the TiN/H13 nitrided substrates and, consequently, the occurrence of coatings chipping. This flaw persists when the nitrided layer is thin, due to an abrupt transition of mechanical properties at the TiN coating / steel core interface. Shorter nitriding times (about 42 min.) and lower nitrogen contents (about N2-5%vol.), on the other hand, are sufficient to guarantee a better adhesion of TiN coatings on AISI D2 tool steel, as the core of such steel possesses relatively better load-bearing capacity than the AISI H13 tool steel. The presence of a black layer at the TiN/nitrided layer interface was observed in all coatings deposited over nitrided layers produced above the threshold nitriding potential curves. This layer affects adversely the wear resistance and the adhesion of the TiN coatings. When higher loads are applied on the coated surface, egg shell type flaws easily occur.

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47

Dézert, Didier. "Etude dans une post-décharge cathode creuse, des transfers d'énergie entre états excités de l'atome de titane, induits par collisions avec des gaz rares et des molécules diatomiques mise en évidence de processus réactifs conduisant à la molécule TiN /". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37604535c.

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48

Clédat, Patrice. "Réalisation et étude comparative de dépôts céramiques obtenus par arc électrique sous vide ou dépôts ioniques : application à l'analyse du comportement anti-usure et des mécanismes de défaillance de revêtements PVD et CVD (TiN, CrN, DLC) sur outils de mise en forme". Limoges, 1999. http://www.theses.fr/1999LIMO4001.

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L'analyse des défaillances d'outils d'emboutissage et l'étude des traitements de surface pouvant y remédier sont les principaux objectifs de l'étude. Les mécanismes de croissance des couches diffèrent selon le procédé de dépôt. Ainsi, dans le cas des dépôts PVD, en arc électrique la majorité des espèces est ionisée alors qu'en dépôts ioniques les espèces métalliques sont neutres. Ceci explique que la taille des grains de CrN est plus faible en arc qu'en dépôts ioniques. Ces mécanismes sont également liés à la nature du dépôt. Ainsi, le titane présente une affinité pour l'azote nettement plus forte que le chrome. Cela conduit à l'incorporation d'azote dans la couche induisant un niveau de contraintes plus élevé pour TiN que pour CrN. Cela explique aussi la difficulté d'obtenir des dépôts stoechiométriques de CrN. Les propriétés mécaniques des revêtements optimisés au laboratoire sont comparables quels que soient la technique PVD et le matériau déposé. Une corrélation entre les propriétés mécaniques et microstructurables des couches a été mise en évidence. En général, la microdureté croît avec le niveau de contraintes qui augmente quand la taille des grains diminue. Une bonne résistance à l'usure nécessite une forte adhérence, obtenue seulement pour des dépôts stoechiométriques. Les caractéristiques des couches optimisées au laboratoire sont comparables à celles des dépôts industriels. L'étude donne des éléments sur la hiérarchisation des traitements sur outil d'emboutissage. Un matériau multicouche obtenu par CVD donne le meilleur résultat. Il est concurrencé par CrN obtenu par PVD qui a une limite de tenue plus basse mais dont le coût est moindre. TiN se révèle moins performant que CrN pour l'emboutissage. Son utilisation est justifiée pour la découpe. Le DLC est limité par son adhérence, alors qu'il est excellent quand un bon frottement est particulièrement recherché. Cette étude pose les bases physiques aux préconisations d'emploi des traitements de surface.

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49

Harman, David Grant y harmandg@hotmail com. "Mechanisms of the Intriguing Rearrangements of Activated Organic Species". The Australian National University. Faculty of Science, 2003. http://thesis.anu.edu.au./public/adt-ANU20031210.143110.

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The β-acyloxyalkyl radical rearrangement has been known since 1967 but its mechanism is still not fully understood, despite considerable investigation. Since the migration of a β-trifluoroacetoxy group generally proceeds more rapidly and with more varied regiochemistry than its less electronegative counterparts, this reaction was studied in the hope of understanding more about the subtleties of the mechanism of the β- acyloxyalkyl radical rearrangement. The mechanism of the catalysed rearrangement of Nalkoxy- 2(1H)-pyridinethiones was also explored because preliminary studies indicated that the transition state (TS) for this process was isoelectronic with TSs postulated for the β-acyloxyalkyl radical and other novel rearrangements. ¶ A kinetic study of the rearrangement of the 2-methyl-2-trifluoroacetoxy-1-heptyl radical in solvents of different polarity was undertaken using a radical clock method. Arrhenius equations for the rearrangement in each solvent were: hexane, log10[kr (s-1)] = 11.8±0.3 – (48.9±0.7)/ θ; benzene, log10[kr (s-1)] = 12.0±0.2 – (43.7±0.8)/ θ; and propionitrile, log10[kr (s-1)] = 11.9±0.2 – (42.0±0.3)/ θ. Rate constants at 75˚C were: hexane, kr = 2.9 × 104; benzene, kr = 2.8 × 105; and propionitrile, kr = 4.0 × 105 s-1. The equilibrium constant for the reversible rearrangement at 80°C in benzene was 15.1

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50

Haouas, Ammar. "Cinetique d'oxydation du monoxyde de carbone sur des catalyseurs cuo sno::(2) : etude physicochimique et simulation informatique". Paris 6, 1988. http://www.theses.fr/1988PA066654.

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Etude cinetique de la reaction de co avec l'oxygene moleculaire en regime dynamique permanent. Etude formelle de la cinetique des reactions de type langmuir avec exploitation au moyen d'un logiciel. Determination experimentale des energies d'activation, des ordres partiels et mecanisme reactionnel

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Tesis sobre el tema "Tion in art"

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