435 resultados para DISLOCATION
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Se analiza una inundación en Argentina y las respuestas desde colectivos artísticos. Se tomaron dos casos comparativamente, "La marca del agua" y "Volver a habitar", ;para observar las diferencias de las intervenciones poscatástrofe. La hermenéutica de la teoría del discurso permitió ajustar la metodología, indagando sobre las formas de procesamiento de la dislocación desde las prácticas, textos lingüísticos y obras de arte. Las intervenciones de carácter antagónico variaron su significación producto del ;contexto en el que se insertaron, mientras las que se orientaron a la reconstrucción de la catástrofe potenciaron relaciones de solidaridad y amistad
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Zr-Excel alloy (Zr-3.5Sn-0.8Nb-0.8Mo) is a dual phase (α + β) alloy in the as-received pressure tube condition. It has been proposed to be the pressure tube candidate material for the Generation-IV CANDU-Supercritical Water Reactor (CANDU-SCWR). In this dissertation, the effects of heavy ion irradiation, deformation and heat treatment on the microstructures of the alloy were investigated to enable us to have a better understanding of the potential in-reactor performance of this alloy. In-situ heavy ion (1 MeV) irradiation was performed to study the nucleation and evolution of dislocation loops in both α- and β-Zr. Small and dense type dislocation loops form under irradiation between 80 and 450 °C. The number density tends to saturate at ~ 0.1 dpa. Compared with the α-Zr, the defect yield is much lower in β-Zr. The stabilities of the metastable phases (β-Zr and ω-Zr) and the thermal-dynamically equilibrium phase, fcc Zr(Mo, Nb)2, under irradiation were also studied at different temperatures. Chemi-STEM elemental mapping was carried out to study the elemental redistribution caused by irradiation. The stability of these phases and the elemental redistribution are strongly dependent on irradiation temperature. In-situ time-of-flight neutron diffraction tensile and compressive tests were carried out at different temperatures to monitor lattice strain evolutions of individual grain families during these tests. The β-Zr is the strengthening phase in this alloy in the as-received plate material. Load is transferred to the β-Zr after yielding of the α-Zr grains. The temperature dependence of static strain aging and the yielding sequence of the individual grain families were discussed. Strong tensile/compressive asymmetry was observed in the {0002} grain family at room temperature. The microstructures of the sample deformed at 400 °C and the samples only subjected to heat treatment at the same temperature were characterized with TEM. Concentration of β phase stabilizers in the β grain and the morphology of β grain have significant effect on the stability of β- and ω-Zr under thermal treatment. Applied stress/strain enhances the decomposition of isothermal ω phase but suppresses α precipitation inside the β grains at high temperature. An α → ω/ZrO phase transformation was observed in the thin foils of Zr-Excel alloy and pure Zr during in-situ heating at 700 °C in TEM.
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Electron beam lithography (EBL) and focused ion beam (FIB) methods were developed in house to fabricate nanocrystalline nickel micro/nanopillars so to compare the effect of fabrication on plastic yielding. EBL was used to fabricate 3 μm and 5 μm thick poly-methyl methacrylate patterned substrates in which nickel pillars were grown by electroplating with height to diameter aspect ratios from 2:1 to 5:1. FIB milling was used to reduce larger grown pillars to sizes similar to EBL grown pillars. X-ray diffraction, electron back-scatter diffraction, scanning electron microscopy, and FIB imaging were used to characterize the nickel pillars. The measured grain size of the pillars was 91±23 nm, with strong <110> and weaker <111> and <110> crystallographic texture in the growth. Load-controlled compression tests were conducted using a MicroMaterials nano-indenter equipped with a 10 μm flat punch at constant rates from 0.0015 to 0.03 mN/s on EBL grown pillars, and 0.0015 and 0.015 mN/s on FIB-milled pillars. The measured Young’s modulus ranged from 55 to 350 GPa for all pillars, agreeing with values in the literature. EBL grown pillars exhibited stochastic strain-bursts at slow loading rates, attributed to local micro yield events, followed by work hardening. Sharp yield points were also observed and attributed to the gold seed layer de-bonding between the nickel pillar and substrate due to the shear stress associated with end effects that arise from the substrate constraint. The onset of yield ranged from 108 to 1800 MPa, which is greater than bulk nickel, but within values given in the literature. FIB-milled pillars demonstrated stochastic yield behaviour at all loading rates tested, yielding between 320 and 625 MPa. Deformation was apparent at FIB-milled pillar tops, where the smallest cross-sectional area was measured, but still exhibited superior yield strength to bulk nickel. The gallium damage at the outer surface of the pillars likely aids in dislocation nucleation and plasticity, leading to lower yield strengths than for the EBL pillars. Thermal drift, substrate effects, and noise due to vibrations within the indenter system contributed to variance and inconsistency in the data.
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Sedimentological and accelerator mass spectrometry (AMS) 14C data provide estimates of the structure and age of five submarine landslides (∼0.4–3 km3) present on eastern Australia's continental slope between Noosa Heads and Yamba. Dating of the post-slide conformably deposited sediment indicates sediment accumulation rates between 0.017 m ka–1 and 0.2 m ka–1, which is consistent with previous estimates reported for this area. Boundary surfaces were identified in five continental slope cores at depths of 0.8 to 2.2 m below the present-day seafloor. Boundary surfaces present as a sharp colour-change across the surface, discernible but small increases in sediment stiffness, a slight increase in sediment bulk density of 0.1 g cm–3, and distinct gaps in AMS 14C ages of at least 25 ka. Boundary surfaces are interpreted to represent a slide plane detachment surface but are not necessarily the only ones or even the major ones. Sub-bottom profiler records indicate that: (1) the youngest identifiable sediment reflectors upslope from three submarine landslides terminate on and are truncated by slide rupture surfaces; (2) there is no obvious evidence for a post-slide sediment layer draped over, or burying, slide ruptures or exposed slide detachment surfaces; and (3) the boundary surfaces identified within the cores are unlikely to be near-surface slide surfaces within an overall larger en masse dislocation. These findings suggest that these submarine landslides are geologically recent (<25 ka), and that the boundary surfaces are either: (a) an erosional features that developed after the landslide, in which case the boundary surface age provides a minimum age for the landslide; or (b) detachment surfaces from which slabs of near-surface sediment were removed during landsliding, in which case the age of the sediment above the boundary surface indicates the approximate age of landsliding. While an earthquake-triggering mechanism is favoured for the initiation of submarine landslides on the eastern Australian margin, further evidence is required to confirm this interpretation.
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Specimens from split Hopkinson pressure bar experiments, at strain rates between ~ 1000–9000 s− 1 at room temperature and 500 °C, have been studied using electron backscatter diffraction. No significant differences in the microstructures were observed at different strain rates, but were observed for different strains and temperatures. Size distribution for subgrains with boundary misorientations > 2° can be described as a bimodal lognormal area distribution. The distributions were found to change due to deformation. Part of the distribution describing the large subgrains decreased while the distribution for the small subgrains increased. This is in accordance with deformation being heterogeneous and successively spreading into the undeformed part of individual grains. The variation of the average size for the small subgrain distribution varies with strain but not with strain rate in the tested interval. The mean free distance for dislocation slip, interpreted here as the average size of the distribution of small subgrains, displays a variation with plastic strain which is in accordance with the different stages in the stress-strain curves. The rate of deformation hardening in the linear hardening range is accurately calculated using the variation of the small subgrain size with strain.
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Background: Medial UKA performed in England and Wales represents 7 to 11% of all knee arthroplasty procedures, and is most commonly performed using mobile-bearing designs. Fixed bearing eliminates the risk of bearing dislocation, however some studies have shown higher revision rates for all-polyethylene tibial components compared to those that utilize metal-backed implants. The aim of the study is to analyse survivorship and maximum 8-year clinical outcome of medial fixed bearing, Uniglide unicompartmental knee arthroplasty performed using an all-polyethylene tibial component with a minimal invasive approach. Methods: Between 2002 and 2009, 270 medial fixed UKAs were performed in our unit. Patients were reviewed pre-operatively, 5 and 8 years post-operatively. Clinical and radiographic reviews were carried out. Patients’ outcome scores (Oxford, WOMAC and American Knee Score) were documented in our database and analysed. Results: Survival and clinical outcome data of 236 knees with a mean 7.3 years follow-up are reported. Every patient with less than 4.93 years follow-up underwent a revision. The patients’ average age at the time of surgery was 69.5 years. The American Knee Society Pain and Function scores, the Oxford Knee Score and the WOMAC score all improved significantly. The 5 years survival rate was 94.1% with implant revision surgery as an end point. The estimated 10 years survival rate is 91.3%. 14 patients were revised before the 5 year follow-up. Conclusion: Fixed bearing Uniglide UKA with an all-polyethylene tibial component is a valuable tool in the management of a medial compartment osteoarthritis, affording good short term survivorship.
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Notre recherche explore quelques moments forts des métamorphoses du rapport politique à la mortalité sous examen des thèmes de l’interdit, de la dignité, de l’autonomie et de l’altérité. Nous dégageons des ancrages propices à nourrir la pensée actuelle en médecine palliative. Ainsi, nous livrons une enquête philosophique, appréciant pour nous Occidentaux, les influences marquantes des pensées gréco-romaine, chrétienne et moderne. Ces bases, édifiant notre monde politique, ont suscité l’émergence de la médecine palliative. C’est pourquoi, nous tentons de caractériser et de comprendre les problématiques nouvelles, dans leurs aspects politique et éthique, envisagées à l’aune des formes contemporaines d’accompagnement des mourants. Notre effort tente de discerner les aspirations et les impasses. L’étude de la métamorphose des repères fait ressortir une dissociation accentuée au fil du temps. En effet, au fur et à mesure, notre entreprise d’interprétation du fondement de ces questions politiques dévoilait : une reconnaissance universelle de l’interdit d’homicide, mais accusant une perte du lien moral au profit d’une visée amorale ; un aval unanime du respect de la dignité, mais manifestant une confusion et une division ostensible entre conceptions intrinsèque et extrinsèque ; une affirmation péremptoire de l’autonomie, mais avec une distanciation marquée au regard de la façon d’envisager la part de l’autre ; une déclinaison de liens humains reconnus de tous, mais exacerbés dans une tension artificielle entre individualisme et altruisme. Au surplus, en constatant la distance et la dislocation entre le public et le privé, entre la réclamation de fraternité et la recherche d’amicalité signifiante, nous avons envisagé la communauté palliative comme un lieu de résistance à cette décomposition menaçante au sein de la communauté politique. À terme de l’analyse, nous avons fondé les concepts « d’allonomie » et de « suspension éthique ». Il s’agit de contributions originales destinées à donner à la philosophie toute sa dimension sapientielle au service de l’accompagnement palliatif.
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We compare the optical properties and device performance of unpackaged InGaN/GaN multiple-quantum-well light-emitting diodes (LEDs) emitting at ∼430 nm grown simultaneously on a high-cost small-size bulk semipolar (11 2 - 2) GaN substrate (Bulk-GaN) and a low-cost large-size (11 2 - 2) GaN template created on patterned (10 1 - 2) r-plane sapphire substrate (PSS-GaN). The Bulk-GaN substrate has the threading dislocation density (TDD) of ∼ and basal-plane stacking fault (BSF) density of 0 cm-1, while the PSS-GaN substrate has the TDD of ∼2 × 108cm-2 and BSF density of ∼1 × 103cm-1. Despite an enhanced light extraction efficiency, the LED grown on PSS-GaN has two-times lower internal quantum efficiency than the LED grown on Bulk-GaN as determined by photoluminescence measurements. The LED grown on PSS-GaN substrate also has about two-times lower output power compared to the LED grown on Bulk-GaN substrate. This lower output power was attributed to the higher TDD and BSF density.
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Resultante dos avanços tecnológicos, conseguiu-se obter um aço que elimina o paradigma de se aliar alta ductilidade e resistência mecânica. Assim foi desenvolvido durante a última década o aço TWIP, deformação induzida por maclação, tendo como principal mecanismo de deformação a maclação. Este presente trabalho teve como principal objetivo caraterizar o aço TWIP980 em três temáticas diferentes: química, mecânica e microestrutura. Na primeira temática, a química, esta teve como objetivo encontrar a designação do aço TWIP em estudo. Sendo apenas conhecida a direção de laminação, RD, e a empresa que forneceu as chapas, a POSCO, o objetivo era obter a sua designação. Através da comparação das curvas de tração encontradas para o material em estudo, e conjuntamente, com as diversas curvas de tração de vários aços TWIP da empresa POSCO, realizou-se a comparação. Visto ter-se ficado reduzido a dois possíveis aços TWIP, foi através de uma análise à composição química, EDS - Espectroscopia da energia dispersa por raios-X, que se concluiu que o aço em estudo era o TWIP980. Na caraterização mecânica, e através de ensaios de tração, foram estudadas propriedades como: o módulo de elasticidade, tensão limite elástico, ductilidade, anisotropia, coeficiente de encruamento e Poisson. Estas propriedades foram estudas para três mudanças na trajetória de deformação e quatro pré-deformações em estudo. Assim estudou-se a alteração de trajetória para os ângulos a 0º, 45º e 90º em relação a RD, para as deformações de engenharia de 0%, 10%, 20% e 30%. Por último, na análise à microestrutura, esta teve como objetivo obter valores para o tamanho de grão e de macla bem como as suas orientações cristalográficas. Também a densidade de deslocações e maclação para cada uma das 4 pré-deformações esteve em estudo. Estes parâmetros foram obtidos através de microscopia ótica, eletrónica de varrimento, MEV e eletrónica de transmissão, MET.
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This chapter examines the poetry of Scottish South Asians, the "New Scots" who bring a whole history of displacement, dislocation and relocation with them, as their memory of the "elsewhere" enters their writing. Their voices are significant as they embody multicultural Scotland with postcolonial dialects that signify an encounter in the Third Space where they are affected by and affect the "host" community. This chapter will question whether the writing of "New Scots" has added more than just "colour" to Scottish Poetry, as it traces the recent migrant history and analyses the lives and "voices" of diasporic communities as evident in their poetry. The objective is to assess how the new "voices" have blended in, expanded and/or challenged the boundaries of what defines Scottish Poetry, and determine whether they form a "community" of poets distinguished by the complexity of their regional allegiances, both past and present.
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The railroad, from 1870 and on, becomes an usual complaining in the press s and politician elite s speeches, especially because of Natal s geographic isolation. The implantation of two railroads in the capital territory Estrada de Ferro de Natal a Nova Cruz, afterwards part of Great Western Railway Company network, and Estrada de Ferro Central do Rio Grande do Norte had serious implications in the urban environment. While railroad s structures were already consolidated, other transportation mechanisms were being implanted in the first decades of the 20th century, such as trams lines, which, by the way, was a transport modal that also used rails as a dislocation meaning. Considering these questions, we may ask: how come railroads and tramways demands, roads and buildings had influenced the internal organization of Natal? We work with the general hypothesis that the influence of technical networks, composed by tramways and railroads, over Natal s urban space happened in a diversified way, sometimes consolidating social aspects in certain areas, sometimes improving the occupation of others. The impact over the city s territory also happens in a diversified way between the buildings/railroad s complexes and the pathways. The different scale of the train in comparison to the trams velocity, size, noise level, flow, among others is also a cause to the different consequences in urban environment. The main objective of this work is to understand the role of circulation technical networks in the construction process of urban space in Natal, as a way to contribute to the urban historiography about the subject. The time frame adopted, between 1881 and 1937, marks the time path of railroads and tramways in Rio Grande do Norte: 1881 is the year of railroad s first section inauguration from Natal to São José do Mipibu as well of the railroad complex in the Republic Square in Natal; the year of 1937 marks the beginning of tramways declination process in the city. At this time railroads and tramways had to face more intensively the competition of motor vehicles. The theory reference adopted is based on concepts and analysis of authors, such as Flávio Villaça and Roberto Lobato Corrêa references to the concepts of urban structure , localization and accessibility and Gabriel Dupuy to explain the concept of urban technical networks . These references reveal the conflict of different realities in the urban universe interests and values which is an important factor about the construction of urban space. The information sources used were from two distinctive natures: primary, journals of the time studied and official government reports, and secondary, based on other works about the subject. It was also used by this study iconographic source, especially images from the data base of the research group História da Cidade, do Território e do Urbanismo .
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The object of this article is to offer a synthesis of the knowledge clarifying the originality and the diversity of the submarine geological formations of the New Caledonian EEZ. A reminder is given onto the geologic history of the region, based upon the dislocation of the Gondwana Continent, the opening of the Tasman Sea, the presence of submarine volcanism, the setting up of heavy peridotitic rocks, the building up of the Fairway and Lord Howe Ridges and of sedimentary basins, the formation of volcanic domes and sea-mounts or guyots, the subduction along the Vanuatu Trench, the uplift of the Loyalty Islands, the development of carbonated ptatforms around the islands etc.... Of this complex history ensues an exceptional submarine geo-diversity. After this presentation the article clarifies the methods and the tools used in marine geosciences to map, explore, observe, analyze, sample, that they are embarked or are autonomous, teleoperated or inhabited systems. A chapter describes the programs which were set up since about forty years and the results obtained as well as the scientific teams concerned with. In conclusion, based on the unpublished character of this geo-diversity, the article introduces the second text to come in a next issue of theTai Kona magazine, text which will focus on the scientific, economic (mineral resources), environmental (deep biodiversity) and risks (seismicity) challenges that are worn by one of the most original submarine geologic context in the world.
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Based on the presupposition that the arts in the West always counted on resources, supports, and devices pertaining to its time context, an reflection is intended regarding the scenic compositions mediated by digital technologies do. Such technologies are inserted in the daily routine, also composing artistic experiments, thus playing a dialogical role with the art/technology intersection. Therefore, the proposal is to investigate what relationships are established in the contemporary theatrical scene from the contagion by digital technologies, aiming at establishing this parallel through a dialogue with the authors discussing the subject, and also based on the group practices having technological resources as a determinant factor in their plays. Furthermore, a reflection should be made on the scene that incorporates or is carried out in intermediatic events, analyzing how digital technologies (re)configure compositional processes of the plays by GAG Phila7, in the city of São Paulo/SP. For such, the dissertation is organized in three sections comprising four moments, to wit: brief overview of the field, contextualization, poetic analysis and synthesis. Qualitative methods are used as the methodological proposal: semi-structure interview, note and document taking (program, website, playing book, disclosure material for advertising text, photographs, and videos). Within the universe of qualitative research, it works with the epistemological perspective of the Gadamer philosophical hermeneutics. The possibilities allowed by the double virtual (Internet/web) generated a type of theater with another material basis and new forms of organization and structure, being possible to perceive that such technological advances and the arts are mutually contaminated, generating a dislocation in the logics of theatrical composition, movement beginning with the artistic vanguards, gradually intensified, thus offering new possibilities of constructions and hybridization of the of the most different possible types. Experiment ―Profanações_superfície de eventos de construção coletiva‖, idealized by Phila7 is inserted in this perspective. Object of the discussion of such research, the experiment works with possible poetics arising from the intersection with the digital technologies, aiming at identifying and problematizing the challenges from the technological evolution and expansion in a scenic context
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Frustrated systems, typically characterized by competing interactions that cannot all be simultaneously satisfied, are ubiquitous in nature and display many rich phenomena and novel physics. Artificial spin ices (ASIs), arrays of lithographically patterned Ising-like single-domain magnetic nanostructures, are highly tunable systems that have proven to be a novel method for studying the effects of frustration and associated properties. The strength and nature of the frustrated interactions between individual magnets are readily tuned by design and the exact microstate of the system can be determined by a variety of characterization techniques. Recently, thermal activation of ASI systems has been demonstrated, introducing the spontaneous reversal of individual magnets and allowing for new explorations of novel phase transitions and phenomena using these systems. In this work, we introduce a new, robust material with favorable magnetic properties for studying thermally active ASI and use it to investigate a variety of ASI geometries. We reproduce previously reported perfect ground-state ordering in the square geometry and present studies of the kagome lattice showing the highest yet degree of ordering observed in this fully frustrated system. We consider theoretical predictions of long-range order in ASI and use both our experimental studies and kinetic Monte Carlo simulations to evaluate these predictions. Next, we introduce controlled topological defects into our square ASI samples and observe a new, extended frustration effect of the system. When we introduce a dislocation into the lattice, we still see large domains of ground-state order, but, in every sample, a domain wall containing higher energy spin arrangements originates from the dislocation, resolving a discontinuity in the ground-state order parameter. Locally, the magnets are unfrustrated, but frustration of the lattice persists due to its topology. We demonstrate the first direct imaging of spin configurations resulting from topological frustration in any system and make predictions on how dislocations could affect properties in numerous materials systems.
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The main theme of this thesis is the social, economic and political response of a single community to economic dislocation in the interwar years. The community under consideration is Clydebank., The thesis is divided into several parts. Part I establishes the development of the burgh and considers the physical framework of the community, mainly in the years before 1919. The town's characteristics are examined in terms of population structure and development between the world wars. In the last part of this section there is a review of the economic structure of the burgh and changes occurring in it between 1919 and 1939. In Part II consideration is given to the actual extent and form of the unemployment affecting Clydebank at this time, and comparison is made with other communities and geographic/economic areas. Attention is then focussed more narrowly on the actual individuals suffering unemployment in the burgh during the 1930s, in an attempt to personalise the experience of the unemployed. Part III reviews central and local government responses to the situation in which Clydebank found itself oetween 1919 and 1939. Central government policies discussed include unemployment insurance, public works, the Special Areas legislation, assistance in the construction of the 534 "Queen Mary" and the direction of financial support to areas of particular need. Amongst local authority actions described are additional local support for the poor, public works, efforts to attract new industry to the town, attempts to deal with the housing problem which was particularly acute at times of high unemployment and measures to maintain health standards in the community. In Part IV the responses of the community to unemployment and government policies are detailed. The burgh's commercial sector is surveyed as are developments in leisure provision, religion, temperance and crime, and local politics. A number of individual responses are also given consideration such as migration, commuting, changes in birth and marriage rates and suicide.