The translational self-diffusion, the librations, and the reorientational motions of guest water molecules in the zeolite chabazite are examined by Molecular Dynamics (MD) computer simulations at different temperatures and loadings, including at room temperature, at which the experiments are carried out. Satisfactory agreement is found between the computed and measured translational self-diffusion coefficients. It is, however, furthermore found that the way in which the long-range electrostatic interactions are computed has an effect on the self-diffusion at high loadings and temperatures. The spectral densities of the librational motions of water are found to be similar to those in aqueous salt solutions. The reorientations of the water molecules, on the other hand, are much slower than in the liquids, and very anisotropic. The vector in direction of the molecular dipole moment reorients only very slowly, at the time scale of the simulations, due to the attraction to the almost immobile Ca++-ions and the walls of the zeolite. The other two vectors seem to undergo jump-reorientations rather than reorientations by a diffusion process. Hyper dynamics boost potential method has been applied to the MD simulations to estimate the self-diffusion coefficients of Ca++ ions in dehydrated chabazite. Because of our system is very complicated, the self-diffusion of Ca++ ions can only be roughly estimated. The Ca++ ions diffusion is small enough to confirm that the cation motion can be neglected in the normal MD simulation.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23176号 / 工博第4820号 / 新制||工||1753(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 林 為人, 教授 福山 英一, 准教授 村田 澄彦 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Problématique : L’accessibilité à des soins de santé de qualité se trouve au cœur des objectifs gouvernementaux en matière de santé. Elle demeure toutefois, et ce depuis de nombreuses années, un point faible de notre réseau bien qu’au cours des cinquante dernières années, de nombreuses recommandations aient été faites afin d’améliorer notre système de santé. Les commissions Castonguay-Nepveu (1967), Rochon (1988) et Clair (2000) ont notamment mis de l’avant l’importance d’améliorer l’accessibilité aux soins de première ligne afin d’offrir de meilleurs soins à l’ensemble de la population. Le problème persiste néanmoins depuis tout ce temps et contribue à l’engorgement des urgences, où plus de 60% des visites sont effectuées par des patients ayant des problématiques de santé considérées comme moins urgentes et non urgentes (Commissaire à la santé et au bien-être, 2016). Parmi les différentes solutions possibles avancées pour désengorger les urgences, la réorientation d’une portion de cette clientèle vers les ressources de première ligne est une des solutions déjà implantées dans plus de la moitié des urgences du Québec (Commissaire à la santé et au bien-être, 2016). Aucune étude, jusqu’à présent, n’a documenté les différents mécanismes de réorientation présents au Québec ni analysé leur fonctionnement. But : Ce mémoire vise donc à documenter et analyser le processus par lequel les patients présentant des problématiques de santé moins urgentes ou non urgentes sont redirigés vers des ressources de soins primaires dans un département d’urgence de la région métropolitaine. Méthodologie : Le devis retenu pour cette étude est un devis qualitatif par étude de cas avec un échantillonnage par choix raisonné composé de cinq personnes provenant d’un département d’urgence (trois infirmières, un gestionnaire infirmier et un médecin). Les résultats ont, par la suite, été analysés en fonction du Patient Care Delivery Model (O’Brien-Pallas, Meyer, Hayes & Wang, 2011) et d’une analyse logique du mécanisme de réorientation étudié. Résultats et discussion : Bien qu’il ait certaines limites évidentes, ce mécanisme de réorientation est apprécié par l’équipe de l’urgence de ce centre où de nombreux effets positifs ont été perçus notamment une diminution du nombre de patients dans la salle d’attente, une diminution du temps d’attente et une diminution perçue de la charge de travail du côté des infirmières du triage. Les différents membres de l’équipe s’entendent pour dire qu’il est sécuritaire et qu’il a permis d’atteindre les objectifs fixés par l’administration. Ce mécanisme pourrait être amélioré, adapté et transféré à d’autres ressources de santé afin d’améliorer la qualité des soins à la population. D’autres études seront cependant nécessaires pour comparer celui-ci à d’autres présents dans la province, mesurer leurs effets et pour ajouter les perceptions des acteurs de soins primaires et la perspective du patient.. Conclusion : Ce mécanisme représente un changement de mentalité au sein des départements d’urgence, passant d’une prise en charge complète des patients se présentant à l’urgence par les médecins d’urgence à une collaboration interprofessionnelle permettant de répartir la prise en charge sur davantage d’acteurs du réseau afin d’améliorer les soins à la population. / Problematic : Access to quality health care services is at the heart of government’s health objectives. For many years, it has remained a weak link in the services offered to the population even though, over the past fifty years, several recommendations have been made in an attempt to improve our health care system. The Castonguay-Neveu commission (1967), the Rochon commission (1988) and the Clair commission (2000) have all put forward the importance of improving access to primary care in order to dispense better care to the entire population. However, the problem remains and contributes to emergency department crowding as over 60% of all visits are made by patients whose health problems can be considered less urgent or non-urgent (Commissaire à la santé et au bien-être, 2016). Amongst the different possible solutions to alleviate emergency department crowding, reorienting a portion of those patients towards a primary care setting is one that has already been implemented in over half of Quebec’s emergency departments (Commissaire à la santé et au bien-être, 2016). So far, no study has documented the different reorientation mechanisms that are present in Quebec, nor have they analysed their functioning. Purpose : This study aims at documenting and analysing the process by which patients coming in the emergency department of the Montreal area with a health problem deemed less urgent or non urgent can be diverted to a primary care setting. Methods: This qualitative study is a case study with a purposive sampling constituted of five participants from an emergency department (three nurses, one head nurse and one emergency physician). Results have then been analysed based on the Patient Care Delivery Model (O’Brien-Pallas et al., 2011) and by logical analysis of this reorientation mechanism. Results and discussion: Even though there are some obvious limits to this study, the reorientation mechanism is appreciated by the emergency department’s staff and several positive effects have been noted such as having fewer patients in the waiting room, lower waiting times for the patients remaining in the waiting room and a perceived reduced workload for the triage nurses. The different team members agree that it is safe and has allowed to achieve the objectives set by the hospital’s administration. This mechanism could be improved, adapted and transferred to other health resources in order to improve the quality of care to the population. Further studies will be needed in order to compare this mechanism with others that are present in the province, to add the perceptions of the primacy care workers and the patient’. It would also be interesting to consider a quantitative approach to measure the outcomes described here. Conclusion: This mechanism represents a mentality shift amongst emergency departments, going from emergency physicians completely taking charge of all patients coming to the emergency department to an interprofessional collaboration that divides the workload on more health care works in the system in order to improve care to the population.

L'élongation cellulaire de cellules cultivant bout comme hyphae fongueux, inculquez hairs, des tubes de pollen et des neurones, est limité au bout de la cellule, qui permet à ces cellules d'envahir l'encerclement substrate et atteindre une cible. Les cellules cultivant bout d'équipement sont entourées par le mur polysaccharide rigide qui régule la croissance et l'élongation de ces cellules, un mécanisme qui est radicalement différent des cellules non-walled. La compréhension du règlement du mur de cellule les propriétés mécaniques dans le contrôle de la croissance et du fonctionnement cellulaire du tube de pollen, une cellule rapidement grandissante d'équipement, est le but de ce projet. Le tube de pollen porte des spermatozoïdes du grain de pollen à l'ovule pour la fertilisation et sur sa voie du stigmate vers l'ovaire le tube de pollen envahit physiquement le stylar le tissu émettant de la fleur. Pour atteindre sa cible il doit aussi changer sa direction de croissance les temps multiples. Pour évaluer la conduite de tubes de pollen grandissants, un dans le système expérimental vitro basé sur la technologie de laboratoire-sur-fragment (LOC) et MEMS (les systèmes micro-électromécaniques) ont été conçus. En utilisant ces artifices nous avons mesuré une variété de propriétés physiques caractérisant le tube de pollen de Camélia, comme la croissance la croissance accélérée, envahissante et dilatant la force. Dans une des organisations expérimentales les tubes ont été exposés aux ouvertures en forme de fente faites de l'élastique PDMS (polydimethylsiloxane) la matière nous permettant de mesurer la force qu'un tube de pollen exerce pour dilater la croissance substrate. Cette capacité d'invasion est essentielle pour les tubes de pollen de leur permettre d'entrer dans les espaces intercellulaires étroits dans les tissus pistillar. Dans d'autres essais nous avons utilisé l'organisation microfluidic pour évaluer si les tubes de pollen peuvent s'allonger dans l'air et s'ils ont une mémoire directionnelle. Une des applications auxquelles le laboratoire s'intéresse est l'enquête de processus intracellulaires comme le mouvement d'organelles fluorescemment étiqueté ou les macromolécules pendant que les tubes de pollen grandissent dans les artifices LOC. Pour prouver que les artifices sont compatibles avec la microscopie optique à haute résolution et la microscopie de fluorescence, j'ai utilisé le colorant de styryl FM1-43 pour étiqueter le système endomembrane de tubes de pollen de cognassier du Japon de Camélia. L'observation du cône de vésicule, une agrégation d'endocytic et les vésicules exocytic dans le cytoplasme apical du bout de tube de pollen, n'a pas posé de problèmes des tubes de pollen trouvés dans le LOC. Pourtant, le colorant particulier en question a adhéré au sidewalls du LOC microfluidic le réseau, en faisant l'observation de tubes de pollen près du difficile sidewalls à cause du signal extrêmement fluorescent du mur. Cette propriété du colorant pourrait être utile de refléter la géométrie de réseau en faisant marcher dans le mode de fluorescence. / Cellular elongation of tip-growing cells such as fungal hyphae, root hairs, pollen tubes and neurons, is limited to the tip of the cell, which enables these cells to invade the surrounding substrate and to reach a target. Tip-growing plant cells are surrounded by the stiff polysaccharidic wall that regulates the growth and elongation of these cells, a mechanism that is very different from non-walled cells. Understanding the regulation of the cell wall mechanical properties in controlling growth and cellular functioning of the pollen tube, a rapidly growing plant cell, is the goal of this project. The pollen tube carries sperm cells from the pollen grain to the ovule for fertilization and on its way from the stigma towards ovary the pollen tube physically invades the stylar transmitting tissue of the flower. To reach its target it also has to change its growth direction multiple times. To assess the behavior of growing pollen tubes, an in vitro experimental system based on lab-on-chip (LOC) technology and MEMS (microelectro-mechanical systems) was designed. Using these devices we measured a variety of physical properties characterizing the pollen tube of Camellia, such as growth velocity, invasive growth and dilating force. In one of the experimental set-ups the tubes were exposed to slit-shaped openings made of elastic PDMS (polydimethylsiloxane) material allowing us to measure the force a pollen tube exerts to dilate the growth substrate. This invasion capacity is crucial for pollen tubes to allow them to enter narrow intercellular spaces within the pistillar tissues. In other assays we used the microfluidic set-up to test whether pollen tubes can elongate in air and whether they have a directional memory. One of the applications that the lab is interested in is the investigation of intracellular processes such as the motion of fluorescently labelled organelles or macromolecules while the pollen tubes grow within the LOC devices. To prove that the devices are compatible with high-resolution optical microscopy and fluorescence microscopy, I used the styryl dye FM1-43 to label the endomembrane system of Camellia japonica pollen tubes. Observation of the vesicle cone, an aggregation of endocytic and exocytic vesicles in the apical cytoplasm of the pollen tube tip, did not pose any problems in pollen tubes located within the LOC. However, the particular dye in question adhered to the sidewalls of the LOC microfluidic network, making viewing of pollen tubes close to the sidewalls difficult because of the highly fluorescent signal of the wall. This property of the dye might be useful to image the network geometry when operating in fluorescence mode.

In der vorliegenden Arbeit wird der Einfluß der reduzierten Translationssymmetrie auf die magnetischen Eigenschaften in dünnen Filmen und an Oberflächen auf der Basis des stark korrelierten Hubbard-Modells untersucht. Zunächst wird die Möglichkeit von spontanem Ferromagnetismus im Hubbard-Modell für translationssymmetrische Systeme diskutiert.Verschiedene Näherungsmethoden zur Lösung des Vielteilchenproblems des Hubbard-Modells werden detailliert beschrieben und mit Ergeb nissen von Quanten-Monte-Carlo-Rechnungen verglichen. Die Konsistenz mit exakten Resultaten über die grobe Struktur der Ein-Teilchen-Spektraldichte im Limes starker Coulomb- Wechselwirkung zwischen den Elektronen erweist sich als essentiell wichtig für eine qualitativ korrekte Beschreibung von spontanem Ferromagnetismus. Das Temperaturverhalten in der ferromagnetischen Phase wird anhand von Magnetisierungs kurven sowie mit Hilfe des spinabhängigen Quasiteilchenspekt rums ausführlich diskutiert. Ein genaues Verständnis der Physik des Volumensystems liefert die Basis für den Übergang zu Systemen mit reduzierter Translationssymmetrie. Es wird eine Methode vorgestellt mit der sich approximative Theorien für das translationssymmetrische Hubbard-Modell auf die Behandlung von Filmsystemen verallgemeinern lassen. Die magnetischen Eigenschaften dünner Hubbard-Filme werden mit Hilfe der lagenabhängigen Magnetisierung als Funktion der Temperatur sowie der Filmdicke diskutiert. Die Abhängigkeit der Curie-Temperatur von der Filmdicke wird untersucht. Insbesondere wird auf die Frage nach der magnetischen Stabilität an der Oberfläche eingegangen. In stark korrelierten Elektronensystemen ist für endliche Temperaturen die magnetische Stabilität an der Oberfläche reduziert im Vergleich zu den inneren Lagen, obwohl auf der Basis des bekannten Stoner-Bildes für Bandmagnetismus genau der gegenteilige Trend zu erwarten wäre. Es wird gezeigt,daß sich dieses Verhalten anhand einfacher Argumente versteh en läßt. Die magnetischen Eigenschaften der Hubbard-Filme lassen sich im Detail mit Hilfe der lokalen Quasiteilchenzus tandsdichte sowie der wellenvektorabhängigen Spektraldichte analysieren. Die elektronische Struktur zeigt eine ausgeprägte Spin-, Lagen- und Temperaturabhängigkeit. In einem weiteren Teil der Arbeit wird der temperaturgetrieb ene Reorientierungsübergang der Magnetisierungsrichtung in dünnen metallischen Filmen untersucht. Dazu müssen die die Hubbard-Filme um anisotrope Beiträge der Dipol-Wechselwir kung und der Spin-Bahn-Wechsel wirkung erweitert werden. Das Wechselspiel von Dipol- und Spin-Bahn-Anisotropie führt unter gewissen Bedingungen zu einem Reorientierungsübergang als Funktion der Temperatur. Im Rahmen des hier vorgestellten Zugangs lassen sich sowohl Reorientierungsüber gänge von einer senkrechten in eine parallele Position ("Fe-artig") als auch Reorientierungsübergänge von einer parallelen in eine senkrechte Position ("Ni-artig") der Magnetisierung qualitativ korrekt beschreiben. / In this work the influence of the reduced translational symmetry on the magnetic properties of thin itinerant-electr on films and surfaces is investigated within the strongly correlated Hubbard model. Firstly, the possibility of spontaneous ferromagnetism in the Hubbard model is discussed for the case of systems with full translational symmetry. Different approximation schemes for the solution of the many -body problem of the Hubbard model are introduced and discussed in detail. It is found that it is vital for a reasonable description of spontaneous ferromagnetism to be consistent with exact results concerning the general shape of the single-electron spectral density in the limit of strong Coulomb interaction between the electrons. The temperature dependence of the ferromagnetic solutions is discussed in detail by use of the magnetization curves as well as the spin-dependent quasiparticle spectrum. For the investigation of thin films and surfaces the approximation schemes for the bulk system have to be generalized to deal with the reduced translational symmetry. The magnetic behavior of thin Hubbard films is investigated by use of the layer-dependent magnetization as a function of temperature as well as the thickness of the film. The Curie-temperature is calculated as a function of the film thickness. Further, the magnetic stability at the surface is discussed in detail. Here it is found that for strong Coulomb interaction the magnetic stability at finite temperatures is reduced at the surface compared to the inner layers. This observation clearly contradicts the well-known Stoner picture of bandmagnetism and can be explained in terms of general arguments which are based on exact results in the limit of strong Coulomb interaction. The magnetic behavior of the Hubbard films can be analyzed in detail by inspecting the local quasiparticle density of states as well as the wave vector dependent spectral density. The electronic structure is found to be strongly spin-, layer-, and temperature- dependent. The last part of this work is concerned about the temperature-driven reorientation transition in thin metallic films. For the description of the magnetic anisotropy in thin films the dipole interaction as well as the spin-orbit interaction have to be included in the model. By calculating the temperature-dependence of the magnetic anisotropy energy it is found that both types of temperature-driven reorientation transitions, from out-of-plane to in-plane ("Fe-type") and from in-plane to out-of-plane ("Ni-type") magnetization are possible within the generalized Hubbard films.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O efeito magnetocalórico, base da refrigeração magnética, é caracterizado por duas quantidades: a variação isotérmica da entropia (ΔST) e a variação adiabática da temperatura (ΔTS); que são obtidas sob variações na intensidade de um campo magnético aplicado. Em sistemas que apresentam anisotropia magnética, pode‐se definir o efeito magnetocalórico anisotrópico, o qual, por definição, é calculado sob variações na direção de aplicação de um campo magnético cuja intensidade mantém‐se fixa, e é caracterizado por duas quantidades: a variação anisotrópico‐isotérmica da entropia (ΔSan) e a variação anisotrópico‐adiabática da temperatura (ΔTan). O efeito magnetocalórico e o efeito magnetocalórico anisotrópico foram estudados nos compostos intermetálicos formados por terras e outros materiais não magnéticos: RNi2, RNi5, RZn e Gd1‐nPrnAl2. Os cálculos foram feitos partindo de hamiltonianos modelo que incluem as interações de troca, Zeeman, de campo cristalino e quadrupolar. / The magnetic refrigeration is based on the magnetocaloric effect. The magnetocaloric potential is characterized by the two thermodynamics quantities: the isothermal entropy change (ΔSiso) and the adiabatic temperature change (ΔTad), which are calculated upon a change in the intensity of the applied magnetic field. In anisotropic magnetic systems it is observed a change in the magnetocaloric effect, since this potential becomes strongly dependent on the direction in which the external magnetic field is applied. The anisotropy in such magnetic systems can lead to an inverse magnetocaloric effect, as well as to the definition of an anisotropic magnetocaloric effect, that by definition is calculated upon a magnetic field which intensity is kept fixed and which orientation is changed from a hard direction of magnetization to the easy direction of magnetization. This anisotropic magnetocaloric effect was performed for the RAl2 intermetallic compounds considering a microscopic model Hamiltonian that includes the Zeeman interaction, the exchange interaction (taken in the mean field approximation) and the crystalline electrical field, that is responsible for the anisotropy in the RAl2 compounds. The anisotropic magnetocaloric was fully investigated for the serie RAl2 and compared with the usual magnetocaloric effect and several curves of (ΔSiso) and (ΔTad) were obtained.

Abstract This research is designed to investigate the occurrence of interdiffusion-induced mesopores, Brownian motion, cleaving and healing and defect clusters in three binary composites, i.e. Ni1-xO/Co1-xO, Ni1-xO/ZrO2 and Co1-xO/ZrO2 of the Ni1-xO-Co1-xO-ZrO2 system. Firstly, the (NimCo1-m)1-£_O/Ni-doped Co3-dO4 composites prepared by reactive sintering Ni1-xO and Co1-xO powders (1:2 molar ratio, denoted as N1C2) at 1000oC with or without further annealing at 720oC in air were studied by X-ray diffraction and electron microscopy to clarify the formation mechanism of mesoporous spinel precipitates. Submicron-sized inter- and intragranular pores, due to incomplete sintering and grain boundary detachment, prevails in (Ni0.33Co0.67)1-£_O protoxide with rock salt structure; whereas nanosize pores due to Kirkendall effect were restricted to the spinel precipitates having Ni component progressively expelled upon annealing. A rapid net vacancy flux and a tensile misfit stress perpendicular to the protoxide/spinel interface caused the formation of elongated and aligned {100}-faceted mesopores in the spinel precipitates with a relatively low equilibrium vacancy concentration. Aligned mesopores in diffusion zone of nonstoichiometric metal oxides have potential applications on thermal barrier bond coating and mass-transport limited heterogeneous catalysis. Also, this thesis deals with the reorientation and shape change of low-crystal-symmetry (non-cubic) ZrO2 within the high-crystal-symmetry grains of Co1-xO/Ni1-xO cubic rock salt-type structure. ZrO2/Co1-xO composites 1:99 and ZrO2/Ni1-xO composites 1:9 in molar ratio were sintered and then annealed at 1650oC for 24 and 100 h in air to induce reorientation of the embedded particles. Transmission electron microscopic observations in both systems indicated that the submicron tetragonal/monoclinic (t/m) ZrO2 particles fell into three topotaxial relationships with respect to the host Co1-xO/Ni1-xO grain: (1) parallel topotaxy, (2) ¡§eutectic¡¨ topotaxy i.e. [100]Z//[111]C,N, [010]Z//[0 1]C,N and (3) ¡§occasional¡¨ topotaxy [100]Z//[111]C,N, [01 ]Z//[0 1]C,N. The parallel topotaxy has a beneficial low energy for the family of {100}Z/C,N and {111}Z/C,N interfaces. The change from the occasional topotaxy to an energetically more favorable eutectic topotaxy was likely achieved by a rotation of the ZrO2 particles over a specific (100)Z/(111)C,N interface. Brownian-type rotation is probable for the embedded t-ZrO2 particles in terms of anchorage release at the interphase interface with the Co1-xO/Ni1-xO host. Detachment or bypassing of rock salt type grain boundaries could also cause orientation as well as shape changes of intergranular ZrO2 particles. Zirconia-polymorphism-induced cleaving and spontaneous healing by precipitation was studied in Co1-xO polycrystals containing a dispersion of ZrO2 particles. Conventional, analytical, and high-resolution transmission electron microscopy indicated that the Co1-xO matrix cleaves parallel to {100} and {110} planes and heals itself by co-precipitation of parallel-topotaxial ZrO2/Co3-£_O4 particles upon cooling. Due to size effect and matrix constraint, nanometer-size ZrO2 precipitates at cleavages were able to retain tetragonality upon further cooling to room temperature. Paracrystalline array of defect cluster was shown to form in Zr-doped Ni1-xO and Co1-xO polycrystals while prepared by sintering at relative high temperature, i.e., 1650oC to increase the defect concentration. Paracrystalline array of defect clusters in Co3-£_O4 spinel structure also occurred when doped with Zr4+ at high temperature or cooled below 900oC to activate oxy-precipitation of Co3-dO4 at dislocations. transmission electron microscopic observations indicated the spinel precipitate and its paracrystal predominantly formed at the ZrO2/Co1-xO interface and the cleavages/dislocations of the Co1-xO host. Defect chemistry consideration suggests the paracrystal is due to the assembly of charge- and volume-compensating defects of the 4:1 type with four octahedral vacant sites surrounding one Co3+-filled tetrahedral interstitial site. The spacing of paracrystalline distribution is 3.3, 2.9 and 4.9 times the lattice parameter for Zr-doped Ni1-xO, Zr-doped Co1-xO and Zr-doped Co3-dO4. This spacing between defect clusters is about 0.98 times that of the previously studied undoped Co3-dO4. There is much larger (3.4 times difference) paracrystalline spacing for Zr-doped Co3-£_O4 than its parent phase of Zr-doped Co1-xO.

Die vorliegende Arbeit präsentiert die ersten detaillierten Untersuchungen des Spin-Reorientierungs-Übergangs in epitaktischen NdCo5-Schichten. Die Proben, die mit gepulster Laserdeposition hergestellt wurden, konnten sowohl als in-plane- als auch als out-of-plane-texturierte Schichten präpariert werden. Für beide Wachstumsvarianten ergaben Röntgendiffraktometrie- und Texturmessungen eine sehr gute Texturierung mit einer nahezu einheitlichen Orientierung der c-Achse, die eine Untersuchung der magnetischen Eigenschaften entlang ausgewählter kristallografischer Richtungen ermöglichte. Die globalen Magnetisierungsmessungen der In-plane-Proben zeigten einen Spin-Reorientierungs-Übergang von einer magnetisch leichten c-Achse für Temperaturen oberhalb von 310 K über einen magnetisch leichten Kegel hin zu einer magnetisch leichten Ebene (a-Achse) unterhalb von 255 K. Die Übergangstemperaturen liegen damit geringfügig über den bisher an Massivproben gemessenen Werten. Aus den magnetischen Hysteresemessungen wurden die magnetokristallinen Anisotropiekonstanten erster und zweiter Ordnung für den Temperaturbereich der magnetisch leichten c-Achse und der magnetisch leichten Ebene ermittelt. Die Untersuchungen der Out-of-plane-Proben wiesen die Existenz einer magnetokristallinen Anisotropie höherer als zweiter Ordnung nach. Sie bewirkt ein unterschiedliches Schaltverhalten der parallel zur a- bzw. b-Achse gemessenen magnetischen Hysteresekurven im Temperaturregime der magnetisch leichten Ebene. Für die in-plane-texturierten Schichten wurde das Domänenmuster und dessen Änderung mit der Temperatur im gesamten Spin-Reorientierungs-Bereich analysiert. Diese Untersuchungen basieren auf in Kooperation mit der Universität Hamburg durchgeführten SEMPA-Messungen. Oberhalb von 318 K liegt eine Zweidomänenkonfiguration mit einer Ausrichtung der Magnetisierung parallel zur c-Achse vor, die beim Abkühlen in das Regime des magnetisch leichten Kegels in einen Vierdomänenzustand übergeht. Unterhalb von 252 K bildet sich eine Zweidomänenkonfiguration mit parallel zur a-Achse orientierter Magnetisierung. Diese lokalen Messungen bestätigten den Spin-Reorientierungs-Übergang mit zu den globalen Magnetisierungsmessungen vergleichbaren Übergangstemperaturen. Für charakteristisch orientierte Domänenwände erfolgten genauere Analysen der Magnetisierungsprozesse in den angrenzenden Domänen. Um ein erweitertes Verständnis der Domänenkonfiguration, deren Temperaturabhängigkeit und der vorhandenen Domänenwände zu erarbeiten, erfolgten mikromagnetische Simulationsrechnungen für ausgewählte Temperaturen. Die Berechnungen wurden sowohl für homogene Systeme als auch für Geometrien mit verschiedenen Pinningzentren durchgeführt. Die Analyse der Domänenwände ergab, dass ihr Bloch- oder Néel-Charakter und die Domänenwandweite von der Temperatur sowie ihrer Ausrichtung parallel zur c- oder a-Achse abhängt. / This thesis presents the first detailed investigation of the spin-reorientation-transition in epitaxial NdCo5 thin films. The samples were prepared by pulsed laser deposition as in-plane or out-of-plane textured films. For both kinds of samples X-ray diffraction and texture measurements revealed a high degree of texture with one common orientation of the c-axis within the film, which allowed an investigation of the magnetic properties along distinct crystallographic directions. Global magnetization measurements of the in-plane textured films showed a spin-reorientation from a magnetic easy axis (c-axis) at temperatures above 310 K via a magnetic easy cone to a magnetic easy plane (a-axis) at temperatures below 255 K. The transition temperatures are slightly higher than values reported for bulk samples. The magnetocrystalline anisotropy constants of first and second order were determined for the regime of the magnetic easy axis and plane. Measurements of the out-of-plane textured films verified the existence of a magnetocrystalline anisotropy of order larger than two, which becomes obvious from a different magnetic switching behavior along the a- and b-axis in the temperature regime of the magnetic easy plane. The domain structure and its changes with temperature were investigated for the in-plane textured films. There exists a two domain state at temperatures above 318 K with an orientation of the magnetization parallel to the c-axis from which a four domain state evolves when cooling down the sample to the easy cone state. Finally, a two domain state exists in the regime of the magnetic easy plane (easy a-axis) with an orientation of the magnetization parallel to the a-axis at temperatures below 252 K. The local measurements confirm the spin-reorientation-transition with transition temperatures comparable to those derived from global magnetization measurements. In addition, a detailed analysis of the magnetization processes for some characteristically oriented domain walls was performed. Micromagnetic simulations were carried out for selected temperatures to achieve a deeper understanding of the temperature dependence of the domain configuration and of the domain walls. The simulations considered homogeneous systems as well as systems with pinning centers. An analysis of the domain walls showed that their character and width depend on temperature and the orientation parallel to the a- or c-axis.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Curricular reorientation based on the Thematic Approach Freirean (TAF) articulated approach to Science, Technology and Society (STS) are possibilities, so that the linear curriculum, preparatory and fragmented schools is questioned and, for that to happen, it is essential to invest in the formation of educators. Thus, the research problem of this research is: What are the possibilities and challenges faced by educators Sciences (Biology, Physics and Chemistry), a public school in Santa Maria, to use the thematic approach in their classes, especially in structuring and implementing the theme "Arroio Cadena: Santa Postcard Maria? "?. In terms of research problem detailing, three objectives were assumed: Discuss how it came to Theme Generator to be developed from the study of Reality (SR); Develop a training collective and interdisciplinary process with educators, aimed at construction / reconstruction of the curriculum through the use of articulated TAF to focus STS; Investigate the possibilities and challenges encountered in the training process and in the development and implementation of educational design / learning. The survey was implemented in the State Preparatory High School Don Antonio Reis, in the city of Santa Maria / RS, during the year 2014. The theoretical reference used in the research is based on the TAF, following the steps of the Three Pedagogical Moments (3PM) as structuring the curriculum, assumptions of the educator Paulo Freire and ideals of focus STS and Latin American Thought in Science Technology and Society (LATSTS). The research was developed in different phases and in the first, It is made explicit the process for obtaining generator theme, from SR, and in the second, the formation process aiming at Thematic Approach (TA). With qualitative approach, the instruments used in the first phase were: document analysis of the school's pedagogical project; research in local newspapers; informal conversations with: Brazilian Institute of Geography and Statistics (BIGS), health post, prefecture, city planning institute and military brigade; interview with students, teachers, directive team and local community. In the second phase, the instruments used were: questionnaire on the first meeting of the formative process, daily researcher, recordings of the encounters of the formative process, teaching projects / elaborate learning, daily educators, interviews with educators and students. As a synthesis of research results initially is discussed as the generator theme emerged: Arroio Cadena: Postcard of Santa Maria? . Just after are discussed two emerging categories of analysis of the whole process using the Text Analysis Discourse (DTA) as methodology: Possibilities of an curricular reorientation the perspective of TA and Challenges of a curricular reorientation the perspective of TA In possibilities, are characteristics such as: interdisciplinary work and the extension of the collective work in school (school and local community), the contributions of the formative process in professional walk of educators, the shift in attitude and dialogue constructed between educator-students and awakening to a culture of participation. In the category of challenges, emerging problems related to the lack of time for interdisciplinary planning, the resistance of students in work developed and yet, the conceptual approach rooted in the concepts and practices. / Reorientações curriculares baseadas na Abordagem Temática Freireana (ATF) articulada ao enfoque Ciência- Tecnologia-Sociedade (CTS) são possibilidades, para que o currículo linear, propedêutico e fragmentado das escolas seja problematizado e, para que isso aconteça, é fundamental investir na formação dos educadores. Assim, o problema de investigação desta pesquisa é: Quais as possibilidades e desafios encontrados por educadores de Ciências (Biologia, Física e Química), de uma escola pública de Santa Maria, ao utilizarem a Abordagem Temática em suas aulas, especialmente na estruturação e implementação do tema Arroio Cadena: Cartão Postal de Santa Maria? . Em termos de detalhamento do problema de pesquisa, três objetivos foram assumidos: Discutir como se chegou ao Tema Gerador a ser desenvolvido, a partir do Estudo da Realidade (ER); Desenvolver um processo formativo coletivo e interdisciplinar com educadores, com vistas à construção/reconstrução do currículo, através da utilização da ATF articulada ao enfoque CTS; Investigar as possibilidades e desafios encontrados no processo formativo e na elaboração e implementação do projeto de ensino/aprendizagem. A pesquisa foi implementada na Escola Estadual de Ensino Médio Dom Antônio Reis, do município de Santa Maria/RS, durante o ano de 2014. O referencial teórico utilizado na pesquisa está fundamentado na ATF, que segue as etapas dos Três Momentos Pedagógicos (3MP) como estruturantes de currículos, pressupostos do educador Paulo Freire e nos ideais do enfoque CTS e do Pensamento Latino Americano em Ciência-Tecnologia-Sociedade (PLACTS). A pesquisa foi desenvolvida em diferentes fases, sendo que, na primeira, é explicitado o processo para obtenção do tema gerador, a partir do ER, e, na segunda, o processo formativo com vistas à Abordagem Temática (AT). Com cunho qualitativo, os instrumentos utilizados na primeira fase foram: análise documental do Projeto Pedagógico da escola; pesquisas em jornais locais; conversas informais com: Instituto Brasileiro de Geografia e Estatística (IBGE), posto de saúde, prefeitura, Instituto de planejamento da cidade e brigada militar; entrevista com educandos, educadores, equipe diretiva e comunidade local. Já na segunda fase, os instrumentos utilizados foram: questionário referente ao primeiro encontro do processo formativo, diários da pesquisadora, gravações dos encontros do processo formativo, projetos de Ensino/Aprendizagem elaborados, diários dos educadores, entrevista com os educadores e educandos. Como síntese dos resultados da investigação, inicialmente, é discutido como emergiu o tema gerador: Arroio Cadena: Cartão Postal de Santa Maria? . Logo após, são discutidas duas categorias emergentes da análise de todo o processo, utilizando a Análise Textual Discursiva (ATD) como metodologia: Possibilidades de uma reorientação curricular na perspectiva da AT e Desafios de uma reorientação curricular na perspectiva da AT. Nas possibilidades, encontram-se características como: o trabalho interdisciplinar e a ampliação do trabalho coletivo na escola (comunidade escolar e local), as contribuições do processo formativo na caminhada profissional dos educadores, a mudança de postura e o diálogo construído entre educador-educandos e o despertar para uma cultura de participação. Na categoria dos desafios, emergem problemas relacionados com a falta de tempo para o planejamento interdisciplinar, as resistências dos educandos no trabalho desenvolvido e, ainda, a abordagem conceitual enraizada nas concepções e práticas.

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