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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

This Woman's Work: Corrosive Power Structures, Gendered Labor and Weariness in Margaret Atwood's The Handmaid's Tale and Oryx and Crake

Pryor, Taylor J 01 January 2020 (has links)
In her 2007 essay “Slow Death (Sovereignty, Obesity, Lateral Agency),” Lauren Berlant asserts that “in the scene of slow death, a condition of being worn out by the activity of reproducing life, agency can be an activity of maintenance” (759). This concept emphasizes the difficulty of maintaining one’s agency while experiencing chronic exhaustion, or what can be referred to as the “wearied state.” Utilizing Berlant’s theoretical framework, this thesis investigates the concept of weariness in two dystopic texts: Margaret Atwood’s The Handmaid’s Tale (1985) and Oryx and Crake (2003). The respective protagonists of The Handmaid’s Tale and Oryx and Crake, Offred and Oryx, each struggle to maintain their agency in the dystopic societies that work to oppress them. Offred, by utilizing wordplay, locates a way to successfully navigate her weariness while simultaneously subverting these who hold power over her. Oryx, oppositely, fails to recognize the sexual power dynamics of her position as a sex slave. Oryx fails to locate her agency, which causes her to normalize her sexually traumatic past. Overall, this thesis argues that weariness need not be final if one makes no attempt to normalize traumatic experiences, remains privy to oppressive ideologies, and retains the ability to cope.
12

Análise de defeitos em tubos de geradores de vapor de usinas nucleares utilizando a transformada de Hilbert-Huang em sinais de inspeção por correntes parasitas / Defects diagnosis of nuclear power plant steam generator tubes using the Hilbert-Huang transform in eddy current testing signals

FORMIGONI, ANDRE L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:55Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
13

Análise de defeitos em tubos de geradores de vapor de usinas nucleares utilizando a transformada de Hilbert-Huang em sinais de inspeção por correntes parasitas / Defects diagnosis of nuclear power plant steam generator tubes using the Hilbert-Huang transform in eddy current testing signals

FORMIGONI, ANDRE L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:35:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:55Z (GMT). No. of bitstreams: 0 / Os tubos de Geradores de Vapor em Reatores Nucleares do tipo PWR são submetidos a diferentes níveis de tensões e carregamento em altas temperaturas, reduzindo sua vida útil devido o surgimento de defeitos e corrosão. A inspeção por Correntes Parasitas é um ensaio não destrutivo usado para diagnosticar defeitos de corrosão e descontinuidades na superfície externa e interna em tubos de trocadores de calor. Esses tubos estão sujeitos a danos por diferentes mecanismos de degradação mecânica e química, tais como trincas por fadiga e corrosão sob tensão. Os sinais de inspeção por Correntes Parasitas são afetados por diferentes ruídos dificultando sua análise pelo inspetor. Esse trabalho apresenta os resultados da análise dos sinais de Correntes Parasitas usando a Transformada de Hilbert-Huang (THH) funcionando como filtro de ruídos (De-noising), como uma técnica alternativa de processamento e análise de sinais. A Transformada de Hilbert-Huang teve esse nome atribuído pela agência espacial norte-americana (NASA) para o resultado da reunião de dois processos, um método de decomposição empiricamente modal (Empirical Mode Decomposition EMD), seguido da análise espectral de Hilbert (Hilbert Spectral Analysis HSA). Os sinais de inspeção por correntes parasitas possuem características de transiente, não estacionário e não linear. A transformada de Hilbert-Huang aplicada neste trabalho forneceu dois recursos alternativos em processamento de sinais; o pré-processamento que funcionou como filtro de ruídos, e outro de análise de sinais, responsável pela identificação das características tempo-frequência-energia do sinal. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
14

Rostfria stålkonstruktioner och rostskyddsbehandling av stålkonstruktioner enligt Eurocode / Stainless steel structures and corrosion protection of steel structures according to Eurocode

Karlsson, Niklas, Öjemyr, Jenny January 2012 (has links)
Steel is an excellent material to build with, but consideration must be given to the fact that unprotected steel corrodes, rusts, therefore, as a rule, the steel must be protected in some way. This can be done by reducing the tendency of the steel to corrode by using stainless steel or by treating the steel with a protection method. The two most common methods of protection are corrosion protection paint and zinc coating. To determine the method, the corrosive category must first be evaluated and this is done in accordance to EN ISO 12944-2:1998. Stainless steel is available in many varieties but only some of them have properties that make them suitable for use as construction steels. There are many factors to be considered in the design of stainless steel to prevent corrosion from occurring. Design of stainless steel is slightly different from the design of plain carbon steel. In this thesis, only the differences are considered. There are many different systems of protective coating. These consist of at least two different layers of paint. Before the steel is painted, it must be pretreated to remove any impurities in the steel in order to get good adhesion. Galvanizing with a zinc coating can be done in a couple of ways, including hot-dip galvanizing and zinc spraying, where galvanizing is the most common method. When both galvanizing and painting is used it is called duplex systems. Which method that should be used depends on several factors such as economics, aesthetics and environmental impact. There is no simple solution, everything must be weighed and considered in each individual case. / Stål är ett utmärkt material att bygga med, men hänsyn måste tas till att oskyddat stål korroderar, rostar, därför ska stålet i regel rostskyddsbehandlas. Detta kan göras genom att minska stålets benägenhet för att korrodera genom att använda rostfritt stål eller genom att behandla stålet med någon skyddsmetod. De två vanligaste skyddsmetoderna är rostskyddsmålning och förzinkning. För att bestämma metod måste först korrosivitetsklassen bedömmas och det görs enligt SS-EN ISO 12944-2:1998. Rostfritt stål finns i många olika varianter och det är bara några av dessa som har egenskaper som gör att de kan användas till byggande. Det finns även många faktorer att tänka på för att förhindra att korrosion i rostfria konstruktioner uppstår. Dimensionering av rostfritt stål skiljer sig något från dimensionering av vanligt kolstål. I detta arbete tas endast skillnaderna upp. Det finns många olika färgsystem inom rostskyddsmålning. Dessa består av minst två stycken olika skikt med färg. Innan ett stål rostskyddsmålas måste det förbehandlas så att eventuella föroreningar på stålet försvinner och ger färgen bra vidhäftning. Förzinkning kan göras på ett par olika sätt, däribland varmförzinkning och sprutförzinkning där varmförzinkning är den vanligaste metoden. När både förzinkning och målning används fås så kallade duplexa system. Vilken metod som ska väljas för att skydda stålet mot korrosion beror på flera olika faktorer så som ekonomi, estetik och miljöpåverkan. Det finns ingen enkel lösningsmetod utan allt måste vägas samman och beaktas utefter varje enskilt fall.
15

Vieillissement thermique de peintures anticorrosion : corrélations entre les évolutions de la chimie, de l'architecture macromoléculaire et des propriétés fonctionnelles / Thermal aging of corrosion resistant coatings : correlations between evolutions of the chemical structure, the macromolecular architecture and the functional properties

Colin, Alexis 10 December 2015 (has links)
Des revêtements multicouche anticorrosion, ou peintures anticorrosion, sont utilisés dans de nombreuses applications industrielles telles que la protection d’emballages métalliques utilisés pour le transport ou l’entreposage de matériaux radioactifs. En conditions d’usage, les propriétés fonctionnelles de ces peintures peuvent être dégradées sous l’effet de la température et des conditions environnementales (lumière, dioxygène, humidité, …). Ces évolutions ont été attribuées au vieillissement des différentes couches de peinture constituant le revêtement anticorrosion (vernis de structure acrylique-siloxane, sous couches de type résine époxydique à durcisseur amine). Afin de mener à bien cette étude, une approche dite « multi-échelle ascendante » a été développée. Cette méthodologie, initialement focalisée sur la modification des propriétés physico-chimiques des polymères vierges constituant chaque couche du revêtement (depuis l’évolution de la structure chimique et de l’architecture macromoléculaire, vers les propriétés fonctionnelles), est ensuite progressivement complexifiée par l’ajout d’additifs à la formulation des peintures (pigments, particules barrières à l’oxydation ou anticorrosion, …) avant que le revêtement multicouche complet ne soit analysé dans son ensemble. Ce travail de thèse vise à identifier et à corréler les modifications de la structure chimique et de l’architecture macromoléculaire des différentes couches de peinture responsables de la modification des propriétés fonctionnelles du revêtement anticorrosion. / Anti-corrosive multilayer coatings, or anti-corrosive paints, are used in several industrial applications such as metallic package protection used for transportation or storage of radioactive materials. In working conditions, functional properties of these paints could be degraded under the influence heat or environmental conditions (light, oxygen, moisture …). Such evolutions had been attributed to the aging of the different paint layers that constituted the anticorrosive coating (acrylic-siloxane topcoat, epoxy resin with amine hardener undercoats). In order to properly carry out this study, a « bottom-up multiscale approach » has been developed. This methodology, initially focused on the physico-chemical modifications of neat polymers that constituted each layer of the coating (from chemical structure and macromolecular architecture evolutions to functional properties), is then complexified by adding filers to the paint formulations (pigments, barrier or anti-corrosive particles …). The complete multilayer coating analyses are the last steps of that methodology. The aim of this thesis is to identify and correlate the evolution of anti-corrosive multilayer coating functional properties to the chemical and architectural modifications in each different layer.
16

Studium trvanlivosti hmot na bázi účelového vzniku ettringitu / Study of durability of binders concept on purposeful creation of ettringite

Sokolt, Stanislav January 2013 (has links)
This master thesis is focused on the binary and ternary systems with connective purposeful ettringite formation for fast hardening adhesive for ceramic tiles. It deals with the durability of these materials after exposure to the corrosive environment. It examines the physical and mechanical properties and mineralogy changes after exposure to corrosive environments. Within processing of this paper provides basic information concerning the connective concept of purposeful formation of ettringite.
17

Vliv kyselého prostředí na žárobetony s rozdílným obsahem cementu. / Effect of acidic influence on the refractory castable with different cement content.

Mátl, Daniel January 2015 (has links)
There are applications of refractory concretes for places where these are exposed to corrosive environments. This diploma thesis deals with both description the corrosive effects and methodology of their testing. One of the most important properties of materials, affecting the chemical corrosion resistance, is their density. The practical part of the thesis is focused on testing the refractory concretes which are currently used for applications. The aggregates were tested for the resistance to sulfuric acid.
18

Développement de nouvelles méthodes de diagnostic et de régénération des huiles pour transformateurs de puissance / Development of modern diagnosticand oils reclamation techniques for power transformers

N'Cho, Janvier Sylvestre 10 March 2011 (has links)
L’indisponibilité d’un transformateur de puissance a de fortes répercussions financières aussi bien pour les exploitants de réseaux d’énergie électriques que pour les clients qui y sont connectés. Afin de prévenir les pannes et d’optimiser la performance de ces équipements d’importance stratégique, de nombreuses techniques et outils de diagnostic ont été développés. L’huile contient environ 70 % des informations de diagnostic sur l’état des transformateurs. Le défi consiste à y accéder et à les utiliser efficacement. L’atteinte d’un tel objectif passe nécessairement par des techniques de diagnostic fiables. En plus des techniques traditionnellement utilisées, trois nouvelles techniques de diagnostic issues des normes ASTM sont utilisées : (1) le test de stabilité qui permet de simuler le comportement sous champ électrique d’une huile en fournissant des informations sur la qualité de celle-ci ; (2) la spectrophotométrie UV/Visible qui permet de mesurer la quantité relative de produits de décomposition dissous dans l’huile ; et (3) la turbidité qui mesure la pureté d’une huile neuve ou usagée. Une méthode quantitative permettant de déterminer les paramètres affectant la formation du soufre corrosif sur les conducteurs en cuivre dans les transformateurs de puissance est proposée. Il est montré entre autres que la tendance au gazage des esters naturels est plus faible que celle de tous les autres types d’huile (minérales, esters synthétiques, silicone). La turbidité et la spectrophotométrie UV/Visible permettent de quantifier efficacement les contaminants qui résultent de l’action d’une décharge électrique sur l’huile isolante. Un nombre important de cycles de régénération (au moins 15) est nécessaire pour qu’une huile vieillie en service retrouve les aptitudes d’une huile neuve. Une nouvelle technique de régénération est présentée pour réduire le nombre de cycles de régénération ; celle-ci consiste à utiliser la terre à foulon traitée avec de l’azote. Il est montré également que le temps constitue le paramètre le plus nuisible dans la formation de soufre corrosif. L’action combinée du temps et de l’agressivité de l’oxygène dissous l’accélère fortement. / A power transformer outage has a dramatic financial consequence not only for electric power systems utilities but also for interconnected customers. In order to prevent any failure and to optimize their maintenance, various diagnostic techniques and tools have been developed. Insulating oil contains about 70% of diagnostic information on the transformer condition. The challenge is to access and use them efficiently. To meet this objective reliable diagnostic techniques are required. In addition to traditional testing methods, three recently developed ASTM testing techniques were used: (1) oil stability testing that simulates the behaviour of oil under electrical stress by providing information on its quality; (2) the UV/Visspectrophotometry that measures the amount of the relative dissolved decay products in insulating oil; and (3) the turbidity that measures the purity of virgin and aged oil. A quantitative laboratory technique capable of determining the parameters affecting the formation of corrosive sulphur deposition on copper conductors in power transformer is proposed. It is shown among other that the gassing tendency of natural esters is lower than that of the other types of insulating fluids (mineral oil, synthetics esters and silicone oil). The turbidity and UV/Vis spectrophotometry allow quantifying effectively, the relative amount of contaminants resulting from electrical discharge in oils. A large number of reclamation cycles (around 15 passes) are required for in-service aged oil to regenerate to the level of new oil. Anew technique enabling reducing the number of reclamation cycles is proposed; this latter consists in the use of Fuller’s Earth previously treated with dry nitrogen. It is also shown that time is the most influential parameter in the formation of corrosive sulfur. The process is accelerated when time and aggressiveness of oxygen are partnered.
19

Trvanlivost sanačních hmot pro železobetonové konstrukce s vyšší odolnosti proti požáru / Durability of repair materials with higher fire resistance for concrete structures

Počekajlo, Václav January 2015 (has links)
This dissertation deals with the study of durability and degradation repair mortars for reinforced concrete structures. In its theoretical part, there are the research findings on the behavior of repair mortars exposed to corrosive environments with different exposure time and selected high temperatures. Processes occurring in repair mortars during their loading at high temperatures or when exposed to chemically aggressive environments are described, We can find recipes designed for cementitious binder based with a specific replacement using slag or fly ash in its practical part. The object of the research was to determine the durability of the proposed repair mortars, and determine their suitability for use on concrete structures, which may be exposed to a synergistic effect of chemically aggressive environments with high temperatures simulating fire.

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