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Peindre la chair : le mouvement de l'image dans l'oeuvre de Chaïm Soutine / Painting the flesh : the image’s movement in Chaïm Soutine’s workPalermo, Chiara 23 November 2013 (has links)
Le travail des peintres qui ont vécu à Paris au début du XXme siècle a souvent consisté en une négation de la représentation qui n’était pas sans rapport avec la négation de l’objet-tableau lui-même : Chaïm Soutine adopte une profonde radicalité dans cette démarche artistique. L’objet de notre étude, suivant son travail, n’est pas la peinture, mais l’action de peindre, de « peindre la chair », pour redéfinir par là même la peinture comme praxis, et penser, à son tour, la philosophie comme pratique qui doit créer son propre faire. En effet, la négation du paradigme de la représentation en peinture nous a conduit à étendre une réflexion jusqu’aux dynamiques expressives de l’art actuel et surtout aux fondements de la pratique philosophique considérée dans l’essence de son mouvement expressif. À ce propos, le thème de la chair illustre à la perfection, en peinture et en philosophie, un dualisme dont notre travail a voulu être le dépassement. Un dualisme critique se polarisant autour de l’opposition entre l’image comme copie-reproduction ou comme autoréférentielle. L’approche ontologique de l’image et du sensible, retracée suivant la pensée de Merleau-Ponty, définit la chair comme prégnance, c’est-à-dire comme un être en différenciation avec lui-même, qu’on ne peut saisir que par un renouvellement de la pensée suivant les mêmes différenciations avec elle-même. Notre analyse de la peinture de Chaïm Soutine conduit à repenser le phénomène esthétique, et, au-delà, à repenser l’être de tout phénomène et de tout apparaître, sans les faire référer aux formules oppositives et aux formes de pensée issues de l’héritage idéaliste de la philosophie et de l’esthétique. / The work of painters who lived in Paris at the beginning of the 20th century mainly consisted in a negation of representation which was not unrelated to the negation of the object-painting itself: Chaïm Soutine brings a deep radical change to this artistic approach. The purpose of our study, according to Soutine’s work, is not its painting, but the action of painting, of "painting the flesh," in order to redefine thereby painting as praxis, and, in turn, philosophy as a practice which must create its own making. Indeed, the denial of the paradigm of representation in painting led us to extend our work to the expressive dynamic reflection of contemporary art and especially to the foundations of philosophical practice considered in the essence of his expressive movement. In this regard, the theme of ‘Flesh’ is a perfect illustration, within painting and philosophy, of a dualism. Our work ambition is to go beyond this dualism. A critical dualism which polarises itself around the opposition between the image as a print-copy/ reproduction and the image as a self –referential. The ontological approach to the 'image' and the 'sensible', drawn by Merleau-Ponty's thought, defines the flesh as pregnancy, that is to say as a Being differentiating of itself which we can only apprehend by renewing our thought following the same differentiation of itself. Our analysis of Chaïm Soutine’s painting lead us to rethink the phenomenon of aesthetics, and, beyond that, to rethink the Being of every phenomena and every appearance without making reference to oppositional forms and ways of thinking from the idealist legacy of philosophy and aesthetics.
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Análise teórica da superfície Si(111)-(7x7)Mikhail, Hanna Degani 31 July 2007 (has links)
In this work, wecarry out theoretical study of the silicon surface reconstruction (7x7)
grown in the [111] direction, denoted by Si(111) (7x7), using the Density Functional
Theory formalism, within the Local Density Approximation (LDA) for the exchange
correlation term. The interaction with the valence electrons and the core ion (nucleus
more core electrons) was described by norm conserving, non local pseudopotential
approach, compatible with the LDA. The one electron Kohn Sham equations was
solved self consistently, by expanding the one electron functions in terms of linear
combination of numerical atomic orbitals. All the calculations were realized using the
Siesta computational code.
Using the clean surface reconstruction model of Si(111) (7x7), propose by Takayanagi
et al.[1, 2], we modeled the surface as a slab, in which the (7x7) unitary cell
contained 200 Si atoms distributed in one adatom layer (Si atoms on the topmost layer)
and the other four layers, with 49 H atoms used for saturate the dangling bonds of the
most internal layer of the slab. The structural analysis of the Si(111) (7x7) reconstructed
surface and the electronic structure analysis showed a good agreement with both the
experimental and theoretical results disposable, reproducing correctly the band structure,
the surface levels and the metallic character of this surface. The obtained energy
per surface atom was 1,132 eV with respect to the bulk energy. It was performed the
study of the vacancy energy formation of adatoms on this surface. We find an average
value of 1,2 eV of a single vacancy formation of adatom the Si(111) (7x7) surface. The
analysis of the energy bands made possible to identify the electronic states due to the
adatoms dangling bonds.
As a first application of the obtained results to the Si(111) (7x7) clean surface, we
investigated the possible states of the physisorption of the chlorobenzene molecules
on specific sites on the Si(111) (7x7) surface. This study showed that chlorobenzene
molecules interact with the surface for distances around 3,0 Å from the adatoms. We
also inferred that the triangular faulted subunit sites are energetically most favorable
to the adsorption than the correspondent triangular unfaulted subunit sites.
We plotted the adsorption energy curve of the chlorobenzene on the corner adatom
at the triangular faulted unitary cell (7x7). The equilibrium distance and the adsorption
energy obtained was 3,005 Å and 0,161 eV, respectively. The magnitude of this
interaction corresponds to a physics adsorption of the chlorobenzene molecule on the
Si(111) (7x7) surface. / Neste trabalho, realizamos o estudo teórico da reconstrução (7x7) da superfície
de Silício crescida na direção [111], denotada por Si(111) (7x7), utilizando para isto o
formalismo da Teoria do Funcional da Densidade, com a Aproximação da Densidade
Local (LDA - LocalDensityApproximation) para o termo de troca correlação. A interação
entre os elétrons de valência e o íon de caroço (núcleo mais os elétrons de caroço) foi
descrita por meio da Teoria dos Pseudopotenciais não locais de norma conservada,
compativel com a LDA. As equações de Kohn Sham de um elétron foram resolvidas
autoconsistentemente, expandindo as funções de um elétronemtermos de combinação
linear de orbitais atômico numéricos, com base double . Todos os cálculos foram
realizados utilizando o código computacional Siesta.
Utilizando o modelo de reconstrução da superfície livre de Si(111) (7x7), proposto
por Takayanagi et al.[1, 2], modelamos a superfície como um slab, cuja célula unitária
(7x7) contém 200 átomos de Si distribuidos em uma camada de adatoms (átomos de Si
adsorvidos sobre a superfície propriamente dita) e quatro outras camadas, além dos
49 átomos de H usados para saturar as ligações pendentes da camada mais interna
ao material. A análise estrutural da superfície reconstruída Si(111) (7x7) e a análise
da estrutura eletrônica mostrou ótima concordância tanto com trabalhos experimentais
quanto teóricos, reproduzindo corretamente a estrutura de bandas, os níveis de
superfície e o caráter metálico desta superfície. A energia obtida em nosso cálculo por
átomo da superfície, com relação à energia bulk, foi de 1,132 eV. Foi feito o estudo da
energia de formação de vacâncias do tipo adatom. Encontramos um valor médio de 1,2
eV para a formação de uma única vacância do tipo adatom na superfície Si(111) (7x7).
A análise da estrutura de bandas do sistema com vacância possibilitou identificar os
estados eletrônicos devido às ligações pendentes dos adatoms.
Como uma primeira aplicação dos resultados obtidos para a superfície livre de
Si(111) (7x7), investigamos possíveis estados de fisiossorção de moléculas de clorobenzeno
sobre sítios específicos sobre a superfície de Si(111) (7x7). Este estudo mostrou
que as moléculas de clorobenzeno interagem com a superfície para distâncias de
aproximadamente 3,0 Å dos adatoms. Também inferimos que sítios da subunidade
triangular faulted são mais favoráveis à adsorção do que sítios correspondentes sobre a
subunidade triangula unfaulted.
Levantamos a curva da energia de adsorção do clorobenzeno sobre o adatom de
canto da subunidade triangular faulted da célula unitária (7x7). A distância de equilíbrio
e a energia de adsorção obtidas foram 3,005 Å e 0,161 eV, respectivamente. A
ordem de grandeza desta interação corresponde a uma adsorção física da molécula de
clorobenzeno sobre a superfície Si(111) (7x7). / Mestre em Física
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Estudo de interações hiperfinas em compostos intermetálicos Gd(Ni, Pd, Cu)In, Tb(Ni, Pd)In, Dy(Ni, Pd)In e Ho(Ni, Pd)InLAPOLLI, ANDRE L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:53Z (GMT). No. of bitstreams: 0 / Neste trabalho investigou-se o comportamento sistemático do campo hiperfino magnético nos compostos intermetálicos Gd(Ni,Pd,Cu)In , Tb(Ni,Pd)In, Dy(Ni,Pd)In e Ho(Ni,Pd)In, com a técnica de Correlação Angular γ-γ Perturbada, nos sítios dos elementos terras raras com o núcleo de prova 140Ce e no sítio do In com o núcleo de prova 111Cd. Os resultados obtidos da dependência com a temperatura do Campo Hiperfino Magnético (Bhf) de cada composto foram primeiramente comparados com a teoria do campo molecular por meio da função de Brillouin, da qual foram extrapolados os valores de saturação de Bhf para cada composto estudado. Os valores extrapolados a zero Kelvin de Bhf (Bhf(T=0)) para os compostos estudados neste trabalho foram usados na comparação com valores de Bhf da literatura para outros compostos contendo o mesmo elemento R (R=Terra Rara). O resultado mostrou uma dependência linear com a temperatura de ordenamento magnético, o mesmo previsto pelo modelo RKKY o que indica que a principal contribuição para Bhf vem da polarização dos elétrons de condução (CEP) via interação de contato de Fermi. O comportamento de Bhf saturado para cada família de compostos de terras raras pesados RNiIn e RPdIn como função da projeção do spin 4f do elemento R mostrou também uma relação linear, com exceção dos resultados para os compostos RNiIn obtidos com 111Cd onde foi observado um leve desvio da linearidade. Foi feita uma investigação dos parâmetros hiperfinos elétricos em função da temperatura para os compostos RPdIn e GdNiIn com o núcleo de prova 111Cd, e os resultados mostram que para o composto GdPdIn pode ocorrer desordem Gd-In a altas temperaturas. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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2D superconductors perturbed by local magnetism : from Yu-Shiba-Rusinov bound states to Majorana quasiparticles / Supraconducteurs 2D perturbés par un magnétisme local : des états de Yu-Shiba-Rusinov aux quasiparticules de MajoranaMénard, Gerbold, Christophe, Bertrand 16 September 2016 (has links)
L'un des buts de la physique de la matière condensée est à l'heure actuelle de fournir de nouveaux systèmes topologiques en particulier dans le domaine de la supraconductivité. L'une des manières envisagée pour générer des supraconducteurs topologiques est d'utiliser une interaction magnétique locale sous la forme de chaînes d'impuretés magnétiques, de vortex ou de clusters d'impuretés magnétiques ordonnées. Dans cette thèse nous avons étudié un ensemble d'effets en partant de l'étude d'impuretés individuelles en allant jusqu'aux clusters organisés en interaction avec un supraconducteur bidimensionnel. En utilisant la microscopie et la spectroscopie tunnel nous avons étudié des monocrystaux de 2H-NbSe$_{2}$ ainsi que les monocouches de Pb/Si(111). En raison du caractère électronique bi-dimensionnel de ces deux systèmes nous avons pu montrer que l'étendue spatiale des états liés induits par des impuretés magnétiques était considérablement augmentée en comparaison avec les supraconducteurs tridimensionnels. En combinant ces atomes magnétiques par auto-assemblage nous sommes parvenus à réaliser des clusters ferromagnétiques qui génèrent une supraconductivité topologique dans la monocouche de Pb. Nous présentons en particulier ici la mesure d'états de bords topologiques à l'interface entre Pb/Si(111) et Pb/Co/Si(111). Nous présentons également la mesure d'états liés à zéro énergie au centre de clusters magnétiques signant la présence de fermions de Majorana dans ces systèmes. / One of the present days goals of condensed matter physics is to create new systems with topological properties, especially in the field of superconductivity. One of the ways envisioned to create topological superconductors is to locally induce a magnetic interaction in the form of chains of magnetic impurities, vortices or magnetic clusters of ordered magnetic impurities. In this thesis we studied a set of effects from individual impurities to organized clusters interacting with two-dimensional superconductors. Using scanning tunneling microscopy and spectroscopy we considered two systems, monocrystals of 2H-NbSe$_{2}$ and monolayers of Pb/Si(111). Thanks to the two-dimensional electronic behavior of these two systems we show how the spatial extent of the bound states induced by magnetic impurities is considerably enhanced compared to the case of a three-dimensional superconductor. By combining these magnetic atoms using a self-assembly method we were able to create ferromagnetic clusters that lead to a topological superconductivity in Pb monolayers. In particular we present here measurement of topological edge states at the interface Pb/Si(111) and Pb/Co/Si(111). We also present the measurement of zero bias peaks in the center of larger magnetic clusters that sign the presence of Majorana fermions in these systems. Our results show that an adequate patterning of surfaces could realize topological patches and call for a pursuit of the efforts in the subject in order to be able to control Majorana fermions that could eventually lead to breakthrough in quantum computation.
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Being and time, §15 : around-for references and the content of mundane concernKelly, Howard Damian January 2014 (has links)
This thesis articulates a novel interpretation of Heidegger’s explication of the being (Seins) of gear (Zeugs) in §15 of his masterwork Being and Time (1927/2006) and develops and applies the position attributed to Heidegger to explain three phenomena of unreflective action discussed in recent literature and articulate a partial Heideggerian ecological metaphysics. Since §15 of BT explicates the being of gear, Part 1 expounds Heidegger’s concept of the ‘being’ (Seins) of beings (Seienden) and two issues raised in the ‘preliminary methodological remark’ in §15 of BT regarding explicating being. §1.1 interprets the being (Sein) or synonymously constitution of being (Seinsverfassung) of a being (Seienden) as a regional essence: a property unifying a region (Region), district (Bezirk), or subject-area (Sachgebiet) – a highly general (‘regional’) class of entities. Although Heidegger posits two components of the being of a being, viz. material-content (Sachhaltigkeit, Sachgehalt) and mode-of-being (Seinsart) or way-of-being (Seinsweise, Weise des Seins, Weise zu sein) (1927/1975, 321), the unclarity of this distinction means that it does not figure prominently herein. §1.2 addresses Heidegger’s distinction between ontological and ontic investigations and his notion of ‘modes of access’ (Zugangsarten, Zugangsweisen). Part 2 expounds §15 of BT’s explication of the being of gear. §2.1 analyses Heidegger’s two necessary and sufficient conditions for being gear and three core basic concepts (Grundbegriffe) enabling comprehension of these conditions and therewith a foundational comprehension of gear. Heidegger explicates the being of gear through content of unreflectively purposeful, non-intersubjective intentional states. I term such states ‘mundane concern’, which is almost synonymous with Hubert Dreyfus’s term ‘absorbed coping’ (1991, 69). Heidegger’s explication highlights around-for references (Um-zu-Verweisungen) as the peculiar species of property figuring in mundanely concernful intentional content. §2.2 clarifies Heidegger’s position on the relationship between to-hand-ness (Zuhandenheit) and extantness (Vorhandenheit) in the narrow sense: two of Heidegger’s most widely discussed concepts. I reject Kris McDaniel’s recent reading of Heidegger as affirming that nothing could be both to-hand and extant simultaneously (McDaniel 2012). Part 3 develops and applies Heidegger’s phenomenology of mundane concern. §3.1 explains the phenomena of situational holism, situated normativity, and mundanely concernful prospective control. §3.2 undertakes the metaphysical accommodation of around-for references, which §3.1 posited as featuring prominently within mundanely concernful intentional content. This thesis thus contributes not only to Heidegger scholarship, but also to contemporary debates within the philosophy of action and cognitive science.
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Aplikace SPM při studiu a modifikaci ultratenkých vrstev Pt, Co a graphenu / Aplication of SPM in study and modification of ultrathin films Pt, Co and grapheneLišková, Zuzana January 2009 (has links)
This diploma thesis deals with the preparation of the very thin films and their investigation by scanning probe microscopy methods. The ultrathin films of Pt on Pt(111) were created by pulsed laser deposition and the ultrathin films of Co on Pt(111) were deposited by thermal evaporation. The coverage of the substrate was much smaller than one monolayer (in order of hundredths of monolayer). The nucleation theory was verified by these experiments using so-called Onset method. Further graphene sheets were prepared on layer of Si/SiO2 by the mechanical exfoliation from the graphite crystal. The fabricated graphene sheets were studied by micro-Raman spectroscopy, microreflectometry, atomic force microscopy and similar techniques. These methods proved the thinnest graphite layers were consisted of two graphene monolayers.
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Epitaxní vrstvy oxidu ceru pro optoelektroniku / Epitaxial films of ceria for opto- electronicsKubát, Jan January 2020 (has links)
This diploma thesis studies magneto-optical (MO) response of epitaxial thin films of Co-doped ceria. Thin films were characterized by XPS, LEED, STM, spectroscopic ellipsometry and measurement of MO activity. The work focuses on studying MO response of the films depending on film thickness, cobalt concentration, oxidation state of cerium and chemical state of cobalt. Spectra of MO response consist of low energy region where the MO activity is mediated by transitions from defect induced states to conduction band and high energy region where a peak of MO activity appears which we attribute to transitions from valence band to conduction band. In this work we qualitatively explain the effects of the physico- chemical states of the thin films on the structure of the obtained MO spectra, mainly on the appearance of the MO activity in the low energy region, and on the changes of the position of the MO peak. Compared to other preparation methods the epitaxial thin films allow achieving a shift of the MO peak in the direction of higher photon energy.
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Studium interakce organických molekul na kovem pasivovaných površích křemíku pomocí STM / Interaction of organic molecules with metal passivated semiconductor surfaces studied via STMZimmermann, Petr January 2019 (has links)
Title Interaction of Organic Molecules with Metal Passivated Silicon Surfaces Studied via STM Author Petr Zimmermann Department Department of Plasma and Surface Science Supervisor Doc. RNDr. Pavel Sobotík, CSc. Department of Plasma and Surface Science Abstract Organic molecules offer a wide range of optical, electronic or chemical properties. Coupling them to silicon could pave way to novel applications and devices, however, a controlled molecular functionalization of silicon remains challenging due to the presence of highly reactive dangling bonds on its surfaces. We attempt to decrease the reactivity of low index silicon surfaces with an ultra-thin layer of a metal adsorbates and study their interaction with organic molecules via scanning tunnelling microscopy. In the first part we investigate the interaction of ethylene, a small unsaturated molecule, with tin and indium 1D chains grown on Si(001) - 2 × 1. The chains consist of dimers structurally analogous to the dimers of the underlying Si(001) - 2 × 1 surface. Aided by photoelectron spectroscopy we find that the Sn chains are less reactive than the Si(001) surface and that the absence of a π dimer bond renders indium chains inert. In the second part we study the interaction of copper phthalocyanine, a small macrocyclic heteroaromatic compound, with the...
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Epitaxní vrstvy oxidu ceru pro optoelektroniku / Epitaxial films of ceria for opto- electronicsKubát, Jan January 2020 (has links)
This diploma thesis studies magneto-optical (MO) response of epitaxial thin films of Co-doped ceria. Thin films were characterized by XPS, LEED, STM, spectroscopic ellipsometry and measurement of MO activity. The work focuses on studying MO response of the films depending on film thickness, cobalt concentration, oxidation state of cerium and chemical state of cobalt. Spectra of MO response consist of low energy region where the MO activity is mediated by transitions from defect induced states to conduction band and high energy region where a peak of MO activity appears which we attribute to transitions from valence band to conduction band. In this work we qualitatively explain the effects of the physico- chemical states of the thin films on the structure of the obtained MO spectra, mainly on the appearance of the MO activity in the low energy region, and on the changes of the position of the MO peak. Compared to other preparation methods the epitaxial thin films allow achieving a shift of the MO peak in the direction of higher photon energy.
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和周波発生振動分光による結晶氷の界面誘起強誘電性に関する研究相賀, 則宏 23 January 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20787号 / 理博第4331号 / 新制||理||1622(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 松本 吉泰, 教授 谷村 吉隆, 教授 寺嶋 正秀 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
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