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BETWEEN HEIMAT AND FREMDE: NEW CONFIGURATIONS OF HAPPINESS IN CONTEMPORARY GERMAN LITERATURE AND FILMHügler, Rebecca Octavia 04 June 2013 (has links)
This thesis investigates representations of happiness in recent German literature and film. The interpretations focus on how happiness is negotiated in the context of home and travel, of Heimat and Fremde, in order to understand happiness, not only insofar as it contributes to “the good life”, but also as an element that shapes public discourses. My readings of works of fiction take into account how notions of happiness have shifted since the turn of the millennium. One reason for this shift is the heightened interest in happiness research, one of the most thriving interdisciplinary research fields of the last decade, which includes disciplines such as psychology, neurosciences, political science, sociology and economics.
The following texts and films are examined in this context: Sommerhaus, später (1998) and Nichts als Gespenster (2003) by Judith Hermann, Transfer Lounge (2003) by Gregor Hens, Die Habenichtse (2006) by Katharina Hacker, Head-On (German: Gegen die Wand, 2004) by Fatih Akın, When We Leave (German: Die Fremde, 2010) by Feo Aladağ, Der Blick hinab (2007) by Shirin Kumm, Unveiled (German: Fremde Haut, 2005) by Angelina Maccarone, Cherry Blossoms (German: Kirschblüten – Hanami, 2008) by Doris Dörrie and Zehn (2010) by Franka Potente.
My theoretical framework is informed in part by Sara Ahmed’s 2010 influential study, The Promise of Happiness, which takes a critical view toward recent happiness research from a cultural studies perspective. My analysis is directed at the ways in which concepts of happiness are narrated, negotiated and challenged within the context of transnational stories, which are inscribed with the effects of “supermodernity” (Augé) in a globalized world. I show how these works subvert themes and motifs that are associated with happiness, such as home and Heimat and travel or migration into the West. Finally, my readings show how these works mediate and reflect public dialogues and traditional notions about what makes us happy or unhappy, and I demonstrate how new configurations of happiness arise from these narratives. / Thesis (Ph.D, German) -- Queen's University, 2013-05-30 17:42:26.632
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Investigação da estrutura local e média de nanopartículas por técnicas de espalhamento e difração de raios X / Local and average structure investigation of nanoparticles using X-ray scattering and diffraction methodsIchikawa, Rodrigo Uchida 19 April 2018 (has links)
Neste trabalho, a estrutura local e média de nanopartículas foi estudada utilizando-se métodos de espalhamento e difração de raios X. Os métodos utilizados foram: Análise da Função de Distribuição de Pares Atômicos (Atomic Pair Distribution Function Analysis, em inglês) para o estudo do ordenamento estrutural de curto alcance, Refinamento de Rietveld e Modelamento Total do Perfil de Difração de Pó para o estudo do ordenamento médio. Os materiais estudados foram: nanopartículas de KY3F10 dopadas com Tb, nanocubos núcleo-camada (core-shell, em inglês) de FeO-Fe3O4 e nanopartículas de ferritas de Mn-Zn. O trabalho teve como objetivo demonstrar como os métodos mencionados podem ser utilizados de forma complementar para fornecer informações de curto, médio e longo alcance usando-se dados de espalhamento e difração de raios X. Neste trabalho, ressalta-se a importância de cada método no estudo da estrutura cristalina e demonstra avanço e desenvolvimento de metodologias para a sua aplicação. / In this work, local and average structure of nanoparticles were studied using X-ray scattering and diffraction methods. The methods used were: Atomic Pair Distribution Function Analysis to study the short-range ordering, Rietveld refinement and Whole Powder Pattern Modelling to study the long-range ordering. The studied materials were: Tb-doped KY3F10 nanoparticles, core-shell FeO-Fe3O4 nanocubes and Mn-Zn ferrite nanoparticles. The objective of this work was to demonstrate how the methods mentioned can be used in a complementary way to provide short, average and long range information about the structure using X-ray scattering and diffraction data. The importance of each method to study the crystalline structure is highlighted demonstrating progress and development of methodologies for its application.
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Investigação da estrutura local e média de nanopartículas por técnicas de espalhamento e difração de raios X / Local and average structure investigation of nanoparticles using X-ray scattering and diffraction methodsRodrigo Uchida Ichikawa 19 April 2018 (has links)
Neste trabalho, a estrutura local e média de nanopartículas foi estudada utilizando-se métodos de espalhamento e difração de raios X. Os métodos utilizados foram: Análise da Função de Distribuição de Pares Atômicos (Atomic Pair Distribution Function Analysis, em inglês) para o estudo do ordenamento estrutural de curto alcance, Refinamento de Rietveld e Modelamento Total do Perfil de Difração de Pó para o estudo do ordenamento médio. Os materiais estudados foram: nanopartículas de KY3F10 dopadas com Tb, nanocubos núcleo-camada (core-shell, em inglês) de FeO-Fe3O4 e nanopartículas de ferritas de Mn-Zn. O trabalho teve como objetivo demonstrar como os métodos mencionados podem ser utilizados de forma complementar para fornecer informações de curto, médio e longo alcance usando-se dados de espalhamento e difração de raios X. Neste trabalho, ressalta-se a importância de cada método no estudo da estrutura cristalina e demonstra avanço e desenvolvimento de metodologias para a sua aplicação. / In this work, local and average structure of nanoparticles were studied using X-ray scattering and diffraction methods. The methods used were: Atomic Pair Distribution Function Analysis to study the short-range ordering, Rietveld refinement and Whole Powder Pattern Modelling to study the long-range ordering. The studied materials were: Tb-doped KY3F10 nanoparticles, core-shell FeO-Fe3O4 nanocubes and Mn-Zn ferrite nanoparticles. The objective of this work was to demonstrate how the methods mentioned can be used in a complementary way to provide short, average and long range information about the structure using X-ray scattering and diffraction data. The importance of each method to study the crystalline structure is highlighted demonstrating progress and development of methodologies for its application.
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Afaga-me as tripas a feiura da porcaria desses romances : experiência estética e poiética escatológica em Haunted, de Chuck Palahniuk e Acenos e Afagos, de João Gilberto Noll, dois romances contemporâneos / Me acaricia las tripas la fealdad de la porquería de estas novelas : experiencia estética y poiética escatológica en Haunted, de Chuck Palahniuk, e Acenos e Afagos, de João Gilberto Noll, dos novelas contemporáneas / Strokes my guts the ugliness of filth these novels : a esthetic experience and eschatological poietic in Haunted, Chuck Palahniuk, and Acenos e Afagos, João Gilberto Noll, two contemporary novelsAldana Nieto, Wilson Julián January 2014 (has links)
Esta é uma tese que salienta a qualidade literária desses dois romances sob a proposta de uma leitura baseada em categorias, desenvolvidas por vários teóricos, como o grotesco, o nojo, a abjeção, o estranho e o sublime. Para atingir este objetivo, levo em conta a crise da beleza e reviso tal conceito segundo a perspectiva de filósofos da Antiga Grécia, a Idade Média, o Iluminismo e século XX. Trata-se de uma proposta de estudo poiético que, a partir do nojento, torna visível a importância do sentido fisionômico na percepção corporal que facilita aos espectadores a experimentação de emoções diante de obras de arte: o “simples” prazer corporal que pode se tornar prazer reflexivo, estético. Com este processo da experiência estética (aisthesis, poiesis, katharsis) através da poiética escatológica, redimensiono o feio nestes romances de Palahniuk e de Noll, na obra de arte, apresentando-o como uma categoria estética que vai além de ser simplesmente o oposto do belo, e se erige como o pináculo de outro cânone. / It is a thesis that highlights the literary quality of the two novels mentioned above. This is to be done through a proposal of reading, based on categories worked by some theoreticians, such as the grotesque, disgust, abjection, the uncanny and the sublime. To achieve this goal, I focus on the crisis of beauty, studying this concept from the perspective of Ancient Greek philosophers, the Middle Ages, the Enlightenment and 20th Century. Furthermore, this deals with a proposal of poetics study that, from the “disgust” perspective, emphasizes the importance of physiognomic sense in the bodily perception, which facilitates spectators to experience emotions about the artwork: the "simple" bodily pleasure becomes “reflective” and “aesthetic” pleasure. Within this process of aesthetic experience (aisthesis, poiesis, katharsis), and through the eschatological poietics, I point out (or address) the ugly of these novels of Palahniuk and Noll, as well as the artwork, presenting it as an aesthetic category that ends to be simply the opposite of beauty and emerges as the pinnacle of another canon. / Es una tesis que resalta la calidad literaria de estas dos novelas, a partir de la propuesta de una lectura basada en categorías, trabajadas por varios teóricos, como lo grotesco, el asco, la abyección, lo siniestro y lo sublime. Para lograr este objetivo, tengo en cuenta la crisis de la belleza y reviso este concepto desde la perspectiva de filósofos de la Antigua Grecia, la Edad Media, la Ilustración y el siglo XX. Se trata de una propuesta de estudio poiético que, a partir de lo asqueroso, destaca la importancia del sentido fisionómico en la percepción corporal que facilita a los espectadores la experimentación de emociones frente a la obra de arte: el “simple” placer corporal que se convierte en placer reflexivo, estético. Con este proceso de experiencia estética (aisthesis, poiesis, katharsis), a través de la poiética escatológica, redimensiono lo feo en estas novelas de Palahniuk y de Noll, en la obra de arte, presentándolo como una categoría estética que deja de ser simplemente lo opuesto a lo bello y se erige como el pináculo de otro canon.
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Regulação da expressão de proteínas de choque térmico pelo vírus da hepatite C / Regulation of heat shock proteins by hepatitis C virusBraga, Ana Claudia Silva [UNESP] 04 August 2017 (has links)
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Previous issue date: 2017-08-04 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O vírus da hepatite C (HCV) causa a doença da Hepatite C e estima-se que cerca de 3% da população mundial esteja infectada com o vírus. A infecção por HCV promove a alteração na expressão de várias proteínas celulares. Estudos têm demonstrado que muitas proteínas de choque térmico (HSPs) possuem um perfil de expressão alterado na presença do vírus e algumas HSPs interagem diretamente com proteínas do HCV. Assim, o presente estudo teve como objetivo avaliar in vitro os níveis de expressão de proteínas de choque térmico na presença e ausência de HCV. Com este propósito, células de hepatoma humano Huh7.5 e células Huh7.5 infectadas com o vírus (HCV JFH-1) foram submetidas à extração de RNA e síntese de cDNA. A expressão diferencial de 84 HSPs e chaperonas foi avaliada por qPCR Array. Os resultados demonstram que cinco genes apresentaram expressão aumentada (em Log2 2), enquanto outros cinco apresentaram expressão reduzida. Para validar estes resultados os 10 genes diferencialmente expressos foram testados por qPCR em três modelos celulares para o HCV: células contendo replicon subgenômico do HCV (SGR-JFH-1), células infectadas com JFH-1 (ambos do genótipo 2a) e células contendo o replicon subgenômico S52 (genótipo 3). O gene HSPB8 mostrou expressão aumentada nos três modelos testados, condizente com os resultados obtidos por qPCR Array. Em seguida, promovemos o silenciamento de HSPB8 e foi observado um aumento na replicação viral. Em contraste, quando aumentamos a expressão de HSPB8, o HCV teve uma diminuição na taxa de replicação. O mesmo procedimento foi adotado para o gene DNAJC5B, validado no modelo viral genótipo 3, e o HCV mostrou padrão de replicação semelhante ao observado para o gene anterior. Esses resultados sugerem que HSPB8 pode atuar como um fator intracelular contra a replicação do vírus da hepatite C e DNAJC5B apresenta a mesma função, mas específico para o genótipo 3. Também avaliamos interações diretas com proteínas do HCV e os resultados demonstraram uma interação física entre a proteína NS4B de HCV e HSPB8. Esses resultados podem contribuir para uma melhor compreensão dos mecanismos envolvidos na replicação do HCV. / Hepatitis C virus (HCV) causes Hepatitis C disease and it is estimated that about 3% of world population are infected with the virus. HCV infection promotes alteration in the expression of several cellular proteins. Studies have shown that many heat shock proteins (HSPs) have an altered expression profile in the presence of the virus and some HSPs interact directly with HCV proteins. Thus, the present study aimed to evaluate in vitro the expression levels of heat shock proteins in the presence and absence of HCV. With this purpose, human hepatoma Huh7.5 cells and Huh7.5 cells infected with the virus (HCV JFH-1) were subjected to RNA extraction and cDNA synthesis. The differential expression of 84 HSPs and chaperones was assessed by qPCR Array. The results demonstrate that five genes showed increased expression (over Log2 2), while five other presented reduced expression. To validate these results, the 10 differentially expressed genes were tested by real-time PCR in three different HCV cell culture models: subgenomic HCV replicon cells (SGR-JFH-1), JFH-1 infected cells (both genotype 2a) and subgenomic S52 cells (genotype 3). The HSPB8 gene showed increased expression in all of three tested models, consistent with qPCR Array results. Then we promoted the silencing of HSPB8 and observed an increase in viral replication. In contrast, when we increased an expression of HSPB8, HCV had a decrease in replication rate. The same procedure was adopted for the DNAJC5B, validated in the viral model genotype 3, and HCV showed replication pattern similar to that observed for the previous gene. These results suggest that HSPB8 may act as an intracellular factor against hepatitis C virus replication and DNAJC5B have the same function, but genotype 3 specific. We also evaluated direct interactions with HCV proteins and the results demonstrated a physical interaction between the HCV NS4B protein with HSPB8. These results can contribute for a better understanding of the mechanisms involved in HCV replication. / FAPESP: 2013/17253-9
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Afaga-me as tripas a feiura da porcaria desses romances : experiência estética e poiética escatológica em Haunted, de Chuck Palahniuk e Acenos e Afagos, de João Gilberto Noll, dois romances contemporâneos / Me acaricia las tripas la fealdad de la porquería de estas novelas : experiencia estética y poiética escatológica en Haunted, de Chuck Palahniuk, e Acenos e Afagos, de João Gilberto Noll, dos novelas contemporáneas / Strokes my guts the ugliness of filth these novels : a esthetic experience and eschatological poietic in Haunted, Chuck Palahniuk, and Acenos e Afagos, João Gilberto Noll, two contemporary novelsAldana Nieto, Wilson Julián January 2014 (has links)
Esta é uma tese que salienta a qualidade literária desses dois romances sob a proposta de uma leitura baseada em categorias, desenvolvidas por vários teóricos, como o grotesco, o nojo, a abjeção, o estranho e o sublime. Para atingir este objetivo, levo em conta a crise da beleza e reviso tal conceito segundo a perspectiva de filósofos da Antiga Grécia, a Idade Média, o Iluminismo e século XX. Trata-se de uma proposta de estudo poiético que, a partir do nojento, torna visível a importância do sentido fisionômico na percepção corporal que facilita aos espectadores a experimentação de emoções diante de obras de arte: o “simples” prazer corporal que pode se tornar prazer reflexivo, estético. Com este processo da experiência estética (aisthesis, poiesis, katharsis) através da poiética escatológica, redimensiono o feio nestes romances de Palahniuk e de Noll, na obra de arte, apresentando-o como uma categoria estética que vai além de ser simplesmente o oposto do belo, e se erige como o pináculo de outro cânone. / It is a thesis that highlights the literary quality of the two novels mentioned above. This is to be done through a proposal of reading, based on categories worked by some theoreticians, such as the grotesque, disgust, abjection, the uncanny and the sublime. To achieve this goal, I focus on the crisis of beauty, studying this concept from the perspective of Ancient Greek philosophers, the Middle Ages, the Enlightenment and 20th Century. Furthermore, this deals with a proposal of poetics study that, from the “disgust” perspective, emphasizes the importance of physiognomic sense in the bodily perception, which facilitates spectators to experience emotions about the artwork: the "simple" bodily pleasure becomes “reflective” and “aesthetic” pleasure. Within this process of aesthetic experience (aisthesis, poiesis, katharsis), and through the eschatological poietics, I point out (or address) the ugly of these novels of Palahniuk and Noll, as well as the artwork, presenting it as an aesthetic category that ends to be simply the opposite of beauty and emerges as the pinnacle of another canon. / Es una tesis que resalta la calidad literaria de estas dos novelas, a partir de la propuesta de una lectura basada en categorías, trabajadas por varios teóricos, como lo grotesco, el asco, la abyección, lo siniestro y lo sublime. Para lograr este objetivo, tengo en cuenta la crisis de la belleza y reviso este concepto desde la perspectiva de filósofos de la Antigua Grecia, la Edad Media, la Ilustración y el siglo XX. Se trata de una propuesta de estudio poiético que, a partir de lo asqueroso, destaca la importancia del sentido fisionómico en la percepción corporal que facilita a los espectadores la experimentación de emociones frente a la obra de arte: el “simple” placer corporal que se convierte en placer reflexivo, estético. Con este proceso de experiencia estética (aisthesis, poiesis, katharsis), a través de la poiética escatológica, redimensiono lo feo en estas novelas de Palahniuk y de Noll, en la obra de arte, presentándolo como una categoría estética que deja de ser simplemente lo opuesto a lo bello y se erige como el pináculo de otro canon.
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Afaga-me as tripas a feiura da porcaria desses romances : experiência estética e poiética escatológica em Haunted, de Chuck Palahniuk e Acenos e Afagos, de João Gilberto Noll, dois romances contemporâneos / Me acaricia las tripas la fealdad de la porquería de estas novelas : experiencia estética y poiética escatológica en Haunted, de Chuck Palahniuk, e Acenos e Afagos, de João Gilberto Noll, dos novelas contemporáneas / Strokes my guts the ugliness of filth these novels : a esthetic experience and eschatological poietic in Haunted, Chuck Palahniuk, and Acenos e Afagos, João Gilberto Noll, two contemporary novelsAldana Nieto, Wilson Julián January 2014 (has links)
Esta é uma tese que salienta a qualidade literária desses dois romances sob a proposta de uma leitura baseada em categorias, desenvolvidas por vários teóricos, como o grotesco, o nojo, a abjeção, o estranho e o sublime. Para atingir este objetivo, levo em conta a crise da beleza e reviso tal conceito segundo a perspectiva de filósofos da Antiga Grécia, a Idade Média, o Iluminismo e século XX. Trata-se de uma proposta de estudo poiético que, a partir do nojento, torna visível a importância do sentido fisionômico na percepção corporal que facilita aos espectadores a experimentação de emoções diante de obras de arte: o “simples” prazer corporal que pode se tornar prazer reflexivo, estético. Com este processo da experiência estética (aisthesis, poiesis, katharsis) através da poiética escatológica, redimensiono o feio nestes romances de Palahniuk e de Noll, na obra de arte, apresentando-o como uma categoria estética que vai além de ser simplesmente o oposto do belo, e se erige como o pináculo de outro cânone. / It is a thesis that highlights the literary quality of the two novels mentioned above. This is to be done through a proposal of reading, based on categories worked by some theoreticians, such as the grotesque, disgust, abjection, the uncanny and the sublime. To achieve this goal, I focus on the crisis of beauty, studying this concept from the perspective of Ancient Greek philosophers, the Middle Ages, the Enlightenment and 20th Century. Furthermore, this deals with a proposal of poetics study that, from the “disgust” perspective, emphasizes the importance of physiognomic sense in the bodily perception, which facilitates spectators to experience emotions about the artwork: the "simple" bodily pleasure becomes “reflective” and “aesthetic” pleasure. Within this process of aesthetic experience (aisthesis, poiesis, katharsis), and through the eschatological poietics, I point out (or address) the ugly of these novels of Palahniuk and Noll, as well as the artwork, presenting it as an aesthetic category that ends to be simply the opposite of beauty and emerges as the pinnacle of another canon. / Es una tesis que resalta la calidad literaria de estas dos novelas, a partir de la propuesta de una lectura basada en categorías, trabajadas por varios teóricos, como lo grotesco, el asco, la abyección, lo siniestro y lo sublime. Para lograr este objetivo, tengo en cuenta la crisis de la belleza y reviso este concepto desde la perspectiva de filósofos de la Antigua Grecia, la Edad Media, la Ilustración y el siglo XX. Se trata de una propuesta de estudio poiético que, a partir de lo asqueroso, destaca la importancia del sentido fisionómico en la percepción corporal que facilita a los espectadores la experimentación de emociones frente a la obra de arte: el “simple” placer corporal que se convierte en placer reflexivo, estético. Con este proceso de experiencia estética (aisthesis, poiesis, katharsis), a través de la poiética escatológica, redimensiono lo feo en estas novelas de Palahniuk y de Noll, en la obra de arte, presentándolo como una categoría estética que deja de ser simplemente lo opuesto a lo bello y se erige como el pináculo de otro canon.
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Recovery of iron and manganese values from metallurgical slags by the oxidation routeSemykina, Anna January 2010 (has links)
In the modern practice, a sustainable development strategy in a domain of wasteutilization is shifting its focus from a general completeness of recycling to a morespecific attention to efficiently utilize elements in the wastes. This is well-illustrated bythe steelmaking slag industries. The major waste product from the steelmaking practiceis slag and its main constituents are: CaO, SiO2, Al2O3, MnO, FeO and so on. The mainfield of application for the steelmaking slags is civil engineering, especially for road andwaterway construction. However, a significant amount of the slag remains in the dumps,damaging the environment as well as requiring a land for secure storage. Efficientrecycling of these materials is of increasing interest worldwide as a result of increasingsustainability in processes with respect to increasing raw material costs and wastereduction.In order to find a practical solution, joint efforts are currently made at the RoyalInstitute of Technology, Sweden and National Metallurgical Academy of Ukraine. Theconcept is based on transformation of non-magnetic wüstite (FeO) to magneticmagnetite (Fe3O4) using an oxidizing atmosphere was proposed.In order to verify the feasibility of the proposed way of slag utilization, experiments onthe ternary CaO-FeO-SiO2 and quaternary CaO-FeO-SiO2-MnO slags systems,accompanied by thermodynamic and kinetic modelling, were performed. The crystalprecipitation during synthetic slag oxidation was observed by Confocal Scanning LaserMicroscopy (CSLM). Precipitated phases were found to be magnetite and manganeseferrite in the spinel form.Obtained magnetite and manganese ferrite can be separated from the slag by magneticseparation.The formation of nanosize manganese ferrite from the CaO-FeO-SiO2-MnO slag systemduring oxidation was investigated. Experiments were conducted in a horizontalresistance furnace in an oxidizing atmosphere (air). The final product was analysed by Xraydiffraction (XRD). The particles size of the manganese ferrite was estimated by theScherrer formula and was found to be of the order of 23-25 nm. In order to get anunderstanding of the magnetic properties of the manganese ferrite recovered from slagtreatment, it was necessary to synthesize a reference compound from pure precursors.The MnFe2O4 nanopowder was synthesized by the oxalate route. The size effects on themagnetic properties of manganese ferrite particles were investigated.IIThe potential way of the magnetite particles separation from liquid slags was investigatedby cold model studies. The experimental technique of mobilising non-conducting,nonmagnetic particles in conducting liquid in crossed electric and magnetic fields wasinvestigated in order to find the way of the particle separation from the liquidsteelmaking slags. The effects of the current density, magnetic field, size and shape ofthe particle on the particle velocity under action of the electromagnetic buoyancy force(EBF) in the electrolyte were analyzed. / QC 20100916
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Epitaktisches Wachstum und Charakterisierung ultradünner Eisenoxidschichten auf Magnesiumoxid(001)Zimmermann, Bernd Josef 17 September 2010 (has links)
Since many years, the importance of thin layers increases for lots of
technical uses. Beginning in the field of microelectronics, the use of thin
layers spread increasingly to other areas. Coatings for surface refining and
optimisation of the mechanical properties for material engineering,
customisation of the surface chemistry in catalysts, as well influencing of
the transmission and reflection characteristics of surfaces in optics are
only some examples of the high scientific and economic weight of the thin
layer technology. Thin magnetic layers are the basis of many known
storage media ranging from the tape recorder to the hard disk up to the
credit card. Nowadays, these thin layers again gain interest in the research
field of nanoelectronics as ultrathin layers. So-called spinvalve-read/write
heads being already installed in actual hard disks use the Tunnel Magneto
Resistance effect for a significant rise in memory density synonymous
capacity. Such read/writeheads consist of a magnetic layersystem. This
use of the magnetic as well as the electric characteristics of the electrons
is called spintronics. The iron oxide magnetite exhibits a high iron portion,
is strong antiferrimagnetic and has a high Curie-temperature. Since many
years, it is used as a magnetic pigment on already mentioned magnetic
tapes. Literature [1, 2, 3, 4] considers ultrathin epitaxial layers of magnetite
on magnesium oxide for uses in the spintronics as a most promising
candidate, because it inheres a complete spin polarisation at Fermi-level.
Moreover, thin magnetite layers serve in the chemical industry as a catalyst
in the Haber- Bosch-procedure and to the dehydration of ethylbenzene to
styrene. Being already used and considered to be of ongoing interest,
ultrathin magnetite layers offer a wide range of technological applications in
many modern industrial and scientific fields. Because there is,
nevertheless, a variety of other iron oxide (cf. chapter 4), it is a matter to
determine the special growth conditions of magnetite. These ultrathin iron
oxide layers were grown reactively on the (001)-surfaces of the magnesium
oxide substrate by molecular beam epitaxy. Besides, the surface is
examined by the diffraction of low-energy electrons concerning its
crystalline structure. X-ray photo electron spectroscopy approaching the
stochiometry completes these first characterisations. Other investigations
are carried out at HASYLAB / DESY in Hamburg by X-ray reflectivity and X-ray
diffraction. The exact thickness of the layers, its crystal properties in bulk, as
well as the thickness of the crystalline portion of the layers can be
determined among other features of the system. The evaluation of XRR-and XRD-investigations is done via simulations with in chapter 5
introduced software packages. The reader finds the theoretical
backgrounds to the used techniques in chapter 3. The experimental setups
in Osnabr¨uck and Hamburg as well as the backgrounds to the
preparation are presented in chapter 5. Because the formation of the
different iron oxides is described in literature [5, 6, 7, 8] as mostly
depending on annealing temperatures, the experimental results in chapter
6 are graded accordingly. The dependence on temperature, layer thickness
and annealing time should be examined for the iron oxides possible on
this substrate. The aim of this work is the preparation of ultrathin epitaxial
iron oxide layers with thicknesses up to few nanometers. The main goal is
to find the growth parameters for ultrathin crystalline magnetite
layers.
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