O concreto armado é um dos materiais de construção mais utilizados atualmente. Um dos fatores que levaram a essa preferência foi a maior durabilidade dos componentes, uma vez que o aço inserido no concreto se protege do ambiente externo e, consequentemente, de uma agressividade intensa pelo cobrimento de concreto empregado. Porém, mesmo considerando que um concreto adequadamente dosado, lançado e curado tende a ser durável, casos de deterioração prematura das estruturas de concreto podem ocorrer, trazendo à tona a importância do controle dos fatores responsáveis pela degradação natural da estrutura. Entre os fatores de deterioração, destaca-se a corrosão de armaduras, devido a sua elevada incidência e potencial de dano. Nas estruturas de concreto armado, são utilizados espaçadores para garantir o cobrimento especificado em projeto e o consequente confinamento do aço, garantindo assim o aumento da vida útil da estrutura. No entanto, a interface espaçador-concreto pode se tornar um ponto frágil para a entrada de agentes agressivos, como os íons cloreto. O objetivo deste trabalho foi avaliar a influência dessa interface utilizando espaçadores de argamassa industrializados e espaçadores de plástico, bem como a condição de exposição a que o concreto é submetido. Para a viabilização do estudo, foi utilizada a técnica de aceleração de corrosão, baseada no ensaio denominado Corrosão Acelerada por Imersão Modificada (CAIM) com aplicação de voltagem constante e corrente constante. Foram moldados corpos de prova em laboratório, com dimensões de 10 × 10 × 20 cm, estabelecidas pelo CAIM, com a utilização de dois tipos de espaçadores e cobrimentos estabelecidos de 25 mm e 50 mm, além de uma barra de aço com diâmetro de 12,5 mm, simulando uma situação real. Para a avaliação dos dados, as amostras passaram por análise microscópica, ensaio colorimétrico e de redimensionamento a laser, a fim de realizar análises qualitativas e quantitativas dos resultados. Este estudo verificou que tanto espaçadores de argamassa quanto de plástico contribuíram para uma maior degradação na região dos espaçadores, porém os de plástico apresentaram desempenho inferior quanto à ascensão de cloretos já na fase da iniciação. Além disso, a condição de exposição por ciclos de calor influencia claramente na interface entre espaçador e concreto, em especial nos espaçadores de plástico. / Reinforced concrete is one of the building materials most used today. One of the factors leading to this constructive choice was greater durability, since the steel is protected for the concrete cover from a strong aggressiveness of the external environment. However, even considering that an adequately dosed, cast and cured concrete, tends to be durable, cases of premature deterioration of concrete structures can occur, bringing to the fore the importance of control the factors responsible for the natural degradation of the structure. Among the deterioration factors, can be highlighted the rebars’ corrosion, because of the high incidence and potential damage. In reinforced concrete structures, spacers are used to ensure structural design specified cover depths and the steel confinement, which helps to increase the structure service life. However, the spacer-concrete interface can become a weak point for the entry of aggressive agents, such as chloride ions. This study aims to understand the influence of the spacer-concrete interface, analysing industrialized mortar spacers and plastic spacers, as well the concrete subjected to different curing condition. In order to make this work possible, a corrosion acceleration technique was used, based on corrosion acceleration test method, with application of constant voltage and constant current. Samples sizing 100 x 100 x 200 mm were cast in the laboratory. The samples were subjected to accelerated corrosion process stimulation, using two different spacers and cover depths (25 mm and 50 mm) and one rebar diameter (12.5 mm), simulating a real situation. The losses of cross section were measured by using microscopic analysis, colorimetric tests and 3D image reconstruction with laser, in order to perform qualitative and quantitative analysis. The results show that both, mortar spacers as plastic spacers, contributed to increase the transport in the contact region, but the plastic spacers produced the largest increase at the first stages. Furthermore, the increase of the temperature in the condition of exposure analysis by heat cycles influences in the interface between spacer and concrete, particularly with the plastic spacers.

O concreto armado é um dos materiais de construção mais utilizados atualmente. Um dos fatores que levaram a essa preferência foi a maior durabilidade dos componentes, uma vez que o aço inserido no concreto se protege do ambiente externo e, consequentemente, de uma agressividade intensa pelo cobrimento de concreto empregado. Porém, mesmo considerando que um concreto adequadamente dosado, lançado e curado tende a ser durável, casos de deterioração prematura das estruturas de concreto podem ocorrer, trazendo à tona a importância do controle dos fatores responsáveis pela degradação natural da estrutura. Entre os fatores de deterioração, destaca-se a corrosão de armaduras, devido a sua elevada incidência e potencial de dano. Nas estruturas de concreto armado, são utilizados espaçadores para garantir o cobrimento especificado em projeto e o consequente confinamento do aço, garantindo assim o aumento da vida útil da estrutura. No entanto, a interface espaçador-concreto pode se tornar um ponto frágil para a entrada de agentes agressivos, como os íons cloreto. O objetivo deste trabalho foi avaliar a influência dessa interface utilizando espaçadores de argamassa industrializados e espaçadores de plástico, bem como a condição de exposição a que o concreto é submetido. Para a viabilização do estudo, foi utilizada a técnica de aceleração de corrosão, baseada no ensaio denominado Corrosão Acelerada por Imersão Modificada (CAIM) com aplicação de voltagem constante e corrente constante. Foram moldados corpos de prova em laboratório, com dimensões de 10 × 10 × 20 cm, estabelecidas pelo CAIM, com a utilização de dois tipos de espaçadores e cobrimentos estabelecidos de 25 mm e 50 mm, além de uma barra de aço com diâmetro de 12,5 mm, simulando uma situação real. Para a avaliação dos dados, as amostras passaram por análise microscópica, ensaio colorimétrico e de redimensionamento a laser, a fim de realizar análises qualitativas e quantitativas dos resultados. Este estudo verificou que tanto espaçadores de argamassa quanto de plástico contribuíram para uma maior degradação na região dos espaçadores, porém os de plástico apresentaram desempenho inferior quanto à ascensão de cloretos já na fase da iniciação. Além disso, a condição de exposição por ciclos de calor influencia claramente na interface entre espaçador e concreto, em especial nos espaçadores de plástico. / Reinforced concrete is one of the building materials most used today. One of the factors leading to this constructive choice was greater durability, since the steel is protected for the concrete cover from a strong aggressiveness of the external environment. However, even considering that an adequately dosed, cast and cured concrete, tends to be durable, cases of premature deterioration of concrete structures can occur, bringing to the fore the importance of control the factors responsible for the natural degradation of the structure. Among the deterioration factors, can be highlighted the rebars’ corrosion, because of the high incidence and potential damage. In reinforced concrete structures, spacers are used to ensure structural design specified cover depths and the steel confinement, which helps to increase the structure service life. However, the spacer-concrete interface can become a weak point for the entry of aggressive agents, such as chloride ions. This study aims to understand the influence of the spacer-concrete interface, analysing industrialized mortar spacers and plastic spacers, as well the concrete subjected to different curing condition. In order to make this work possible, a corrosion acceleration technique was used, based on corrosion acceleration test method, with application of constant voltage and constant current. Samples sizing 100 x 100 x 200 mm were cast in the laboratory. The samples were subjected to accelerated corrosion process stimulation, using two different spacers and cover depths (25 mm and 50 mm) and one rebar diameter (12.5 mm), simulating a real situation. The losses of cross section were measured by using microscopic analysis, colorimetric tests and 3D image reconstruction with laser, in order to perform qualitative and quantitative analysis. The results show that both, mortar spacers as plastic spacers, contributed to increase the transport in the contact region, but the plastic spacers produced the largest increase at the first stages. Furthermore, the increase of the temperature in the condition of exposure analysis by heat cycles influences in the interface between spacer and concrete, particularly with the plastic spacers.

A espessura de cobrimento das armaduras, que se interpõe entre as barras de aço e o ambiente proporcionando proteção contra os agentes agressivos, é fator determinante na durabilidade das estruturas de concreto armado. Embora o emprego do espaçador para assegurar o cobrimento especificado seja normatizado, a regulamentação brasileira não dispõe nenhum método de fixação e distribuição dos dispositivos. Levantamentos in loco efetuados durante esta pesquisa, em obras localizadas em Porto Alegre/RS e Cuiabá/MT, mostraram através de medições em elementos estruturais já executados, que as espessuras de cobrimento estão não conformes com as especificações de projeto. Dentro deste levantamento, os resultados mais preocupantes estão relacionados ao fundo de viga e lajes. Para lajes de concreto armado, notou-se durante a execução, que alguns fatores poderiam influenciar na obtenção deste requisito proposto em norma. Sendo assim, buscou-se testar através de simulação computacional diferentes combinações de variáveis, como por exemplo, a distribuição de espaçadores, as características da armadura e o carregamento acidental presente durante a concretagem. Diante dos resultados apresentados pelo estudo computacional, onde um grande percentual de combinações apresenta a plastificação total das barras de aço, testou-se em laboratório alguns conjuntos de variáveis, a fim de mensurar a deformação permanente na malha de armadura. Foi possível constatar que armaduras compostas com diâmetros de 4,2 mm e 5,0 mm, apresentam resultados críticos na obtenção da espessura de cobrimento, independentemente da distribuição dos espaçadores, deformando permanentemente a armadura chegando a um valor de 17,31 mm, e assim, prejudicando diretamente a durabilidade da estrutura de concreto armado. / The cover to reinforcement ensures durability, it is responsible for protecting the armor front the environment aggressive agents. The use of spacers is a recommendation standard, however the regulation does not provide sufficiente methodology of use subsidies. Thus, cover to reinforcement just barely achieved during the structural element execution as show in this research, through surveys conducted in the cities of Porto Alegre/RS and Cuiabá/MT. With that, by computer and experimental simulation, some variables observed during the solid slabs execution, such as armor characteristics, overlays thickness and spacers distribution were tested in different configurations. The results shows that the smaller diameter reinforcements (4,2 and 5,0 mm) create critical situations in relation to overlays obtainment, independent of the configuration, all the reinforcements suffer permanent deformation, reaching 17,31 mm, affecting the performance of the reinforced concrete structure.

A espessura de cobrimento das armaduras, que se interpõe entre as barras de aço e o ambiente proporcionando proteção contra os agentes agressivos, é fator determinante na durabilidade das estruturas de concreto armado. Embora o emprego do espaçador para assegurar o cobrimento especificado seja normatizado, a regulamentação brasileira não dispõe nenhum método de fixação e distribuição dos dispositivos. Levantamentos in loco efetuados durante esta pesquisa, em obras localizadas em Porto Alegre/RS e Cuiabá/MT, mostraram através de medições em elementos estruturais já executados, que as espessuras de cobrimento estão não conformes com as especificações de projeto. Dentro deste levantamento, os resultados mais preocupantes estão relacionados ao fundo de viga e lajes. Para lajes de concreto armado, notou-se durante a execução, que alguns fatores poderiam influenciar na obtenção deste requisito proposto em norma. Sendo assim, buscou-se testar através de simulação computacional diferentes combinações de variáveis, como por exemplo, a distribuição de espaçadores, as características da armadura e o carregamento acidental presente durante a concretagem. Diante dos resultados apresentados pelo estudo computacional, onde um grande percentual de combinações apresenta a plastificação total das barras de aço, testou-se em laboratório alguns conjuntos de variáveis, a fim de mensurar a deformação permanente na malha de armadura. Foi possível constatar que armaduras compostas com diâmetros de 4,2 mm e 5,0 mm, apresentam resultados críticos na obtenção da espessura de cobrimento, independentemente da distribuição dos espaçadores, deformando permanentemente a armadura chegando a um valor de 17,31 mm, e assim, prejudicando diretamente a durabilidade da estrutura de concreto armado. / The cover to reinforcement ensures durability, it is responsible for protecting the armor front the environment aggressive agents. The use of spacers is a recommendation standard, however the regulation does not provide sufficiente methodology of use subsidies. Thus, cover to reinforcement just barely achieved during the structural element execution as show in this research, through surveys conducted in the cities of Porto Alegre/RS and Cuiabá/MT. With that, by computer and experimental simulation, some variables observed during the solid slabs execution, such as armor characteristics, overlays thickness and spacers distribution were tested in different configurations. The results shows that the smaller diameter reinforcements (4,2 and 5,0 mm) create critical situations in relation to overlays obtainment, independent of the configuration, all the reinforcements suffer permanent deformation, reaching 17,31 mm, affecting the performance of the reinforced concrete structure.

The primary aim was to validate and implement a urinary pharmacokinetic method for terbutaline to determine the relative lung and systemic bioavailability following inhalation and to measure the in-vitro characteristics of the emitted dose by these inhalation methods. Two new robust, accurate and sensitive high performance liquid chromatography methods for the determination of terbutaline in aqueous and urine samples were validated in accordance with the FDA and ICH guidelines. Terbutaline was extracted using solid phase extraction with salbutamol and bamethane as internal standards. The accuracy, precision, lower limit of detection and recovery for both methods were within recognized limits. The in-vitro characteristics of terbutaline sulphate inhalers were measured according to standard compendial methodology as well as adaptation of this methodology to simulate routine patient use. The dose emission of terbutaline sulphate from a Bricanyl Turbuhaler was determined using an inhalation volume of 4 L at inhalation flows of 10-60 L min-1. The particle size distribution was measured using an Anderson Cascade Impactor (ACI) with a mixing inlet valve to allow measurement at different flows. A steady increase in total emitted dose (TED) and the fine particle dose (FPD) was observed as the inhalation flow increased thereby highlighting the flow dependent dose emission characteristics of the Turbuhaler. The in-vitro dose emission characteristics of terbutaline sulphate from Bricanyl MDIs were measured according to the standard compendial methodology at a flow of 28.3 L min-1 using a 4 L inhalation volume. The TED and particle size distribution of terbutaline sulphate from the Bricanyl MDI were determined alone and with different spacers [AeroChamber Max (AMAX), AeroChamber Plus (APLUS), Fisonair and Nebuhaler]. The TED from the MDI alone was significantly higher than all MDI+spacers (p<0.001). The MDI with APLUS resulted in the smallest mass median aerodynamic diameter (MMAD) and the highest fine particle fraction (FPF). The MDI with AMAX resulted in the highest FPD. The in-vitro characteristics of terbutaline sulphate from Bricanyl respules using the Aeroneb Pro (vibrating mesh) and Sidestream jet nebulisers were determined by the CEN methodology and the Next Generation Impactor (NGI) methodology. The Aeroneb Pro was found to have significantly better aerodynamic properties than the Sidestream. The results from the NGI method were significantly different from the CEN method suggesting further evaluation of both methods. Cooling the NGI decreased the evaporation effect. Twelve healthy volunteers (6 females) completed in-vivo urinary terbutaline pharmacokinetic studies to determine the relative bioavailability following inhalation. The differences between the amounts excreted 0.5, 1, 2, 4, 6 and 24 hour post inhalation from a Bricanyl MDI (I) and oral (O) dosing of 500 µg terbutaline sulphate and with the co-administration of oral charcoal (IC and OC, respectively) were studied. No terbutaline was found in OC samples. The amount of terbutaline excreted 30 minutes post I and IC were significantly (p<0.001) higher than post O suggesting that the amount of terbutaline excreted 30 minutes post dosing can be used as an index of the lung deposition. The amount of terbutaline excreted 24 hour post I was significantly (p<0.01) higher than post O suggesting that the amount of terbutaline excreted 24 hour post dosing can be used as an index of the relative systemic bioavailability. The dose response relationships and the low inter and intra-subject variability studies confirm the feasibility of this method. To demonstrate the application of the method the effect of inhalation technique on the lung and systemic bioavailability following inhalation from a dry powder inhaler was evaluated. The effect of different spacers on the dose emitted from the Bricanyl MDI and the effect of different nebulisers on the dose emitted were also studied using twelve healthy volunteers (6 females) for each study. A fast inhalation flow using the Bricanyl Turbuhaler resulted in significantly higher amounts of terbutaline excreted 0.5 and 24 hour post dosing (2 doses of 500µg terbutaline sulphate from Bricanyl Turbuhaler) than slow inhalation flow (p<0.001). The Bricanyl MDI alone resulted in a significantly higher amount of terbutaline excreted 24 hour post dosing (2 doses of 250µg terbutaline sulphate from Bricanyl MDI) and significantly lower amounts excreted 30 minutes post dosing than the MDI+Spacers. The AMAX provided a greater amount of urinary terbutaline excreted 30 minutes post dosing than the APLUS and Nebuhaler. The Aeroneb Pro resulted in significantly higher amounts of terbutaline excreted 0.5 and 24 hour post dosing (1 dose of 5mg/2ml terbutaline sulphate from Bricanyl respule) than a Sidestream Jet nebuliser (p<0.001). Further application of the method was demonstrated by 12 (6 female) COPD non-invasive mechanically ventilated patients. One dose of 2mg in 0.8ml terbutaline sulphate respiratory solution from Aeroneb Pro and one dose of 5mg in 2ml terbutaline sulphate respiratory solution from Sidestream jet nebuliser resulted in a similar amounts of urinary terbutaline excreted 0.5 and 24 hour post dosing. The results were consistent with the results of the ex-vivo study performed on the same patients. The thesis highlights extension of the urinary pharmacokinetic method following inhalation to terbutaline and its application in volunteer and patient studies. / Egyptian Culture Office in UK, Missions Department in Egypt

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Diese Arbeit ist das Ergebnis von mehr als 35 Jahren Erfahrung mit Hochspannungsfreileitungen, 25 Jahre davon sind durch die intensive Beschäftigung mit Silikonverbundisolatoren stark geprägt worden. Verbundisolatoren werden inzwischen als gleichwertige Alternative zu Porzellan- und Glasisolatoren anerkannt und weltweit in großen Stückzahlen eingesetzt. Durch die Verschiedenartigkeit seiner Komponenten ist die Wechselwirkung zwischen mechanischer und elektrischer Integrität bei einem Verbundisolator von großer Bedeutung. Man denke z.B. an die Auswirkung von Rissen im glasfaserverstärkten Kern, die durch unzureichende mechanische Auslegung entstehen und Teilentladungen bzw. im schlimmsten Fall einen inneren Durchschlag verursachen können. In diesem Sinne untersucht diese Arbeit , nach einer kurzen Einleitung, die verschiedenen Bauarten von Verbundisolatoren, d.h. Verbundlangstäbe, Verbundstützer, Isoliertraversen für Kompaktleitungen und Phasenabstandshalter; insbesondere für letztere werden neue Erkenntnisse zu deren mechanischen Bemessung hier erstmalig veröffentlicht.:1 Einleitung 1.1 Vorteile und Entwicklung von Verbundisolatoren 1.2 Erfahrungen mit Verbundisolatoren 1.3 Einsatz von Verbundisolatoren in Hochspannungsfreileitungen 1.4 Einsatz von Verbundisolatoren bei elektrischen Apparaten und Freiluftschaltanlagen. 1.5 Stand der Normung 2 Verbundlangstabisolatoren 2.1 Anwendungen von Verbundlangstabisolatoren 2.2 Das Verhalten von Verbundlangstabisolatoren unter mechanischer Beanspruchung 2.2.1 Die Dauerstandfestigkeit von Verbundlangstabisolatoren 2.2.1.1 Die Dauerkraftkurve von Verbundisolatoren nach IEC 61109/92 2.2.1.2 Mechanisches Modell für das Langzeitverhalten von Verbundisolatoren 2.3 Verhalten von Verbundlangstabisolatoren bei dynamischer Belastung 2.4 Auslegung und Montage von Endarmaturen für Verbundlangstäbe 2.4.1 Entwicklung und Stand der Technik der Metallarmaturen 2.4.2 Grundsätzliche Überlegungen zu der Auslegung von Pressarmaturen 2.4.3 Montagetechnik von Pressarmaturen 2.4.4 Berechnungssystematik 2.4.5 Einfache analytische Methode 2.4.6 Fortgeschrittene analytische Methode 2.4.6.1 Verpressung 2.4.6.2 Relaxation 2.4.6.3 Zugbelastung/Pull-out 2.4.7 Numerische Simulation 2.4.7.1 Finite Elemente Modell 2.4.7.2 Rechenergebnisse der Simulation 2.4.7.3 Ergebnisse der numerischen Versagenssimulation 2.4.7.4 Versuchsergebnisse 2.4.7.5 Sensitivitätsanalyse 2.5 Formelzeichen und Abkürzungen 3 Verbundstützisolatoren 3.1 Wesentliche Eigenschaften 3.2 Anwendungen von Verbundstützisolatoren 3.3 Das Verhalten von Verbundstützisolatoren unter Biegung 3.3.1 Allgemeines 3.3.2 Einführung einer Schadensgrenze (damage limit) 3.3.2.1 Versuche zur Bestimmung der Schadensgrenze 3.3.2.2 Versuch zur Bestimmung der maximalen Betriebsbiegelast (MDCL) 3.3.2.3 Bestimmung der MDCL und der SCL im gleichen Versuch 3.4 Herstellerangaben zum SCL/MDCL Konzept 3.5 Das sichere Verhalten beim Versagen von Verbundstützern (safe failure mode) 3.6 Kombinierte Belastungen 3.6.1 Lastdiagramme 3.6.2 Beispiele 3.6.2.1 Horizontale Lage des Isolators 3.6.2.2 Isolator bildet einen Winkel von β = 15° zur Horizontalen 3.6.3 Computersimulation 3.6.4 Versuche 3.7 Dynamische Belastungen 3.7.1 Prüflinge 3.7.2 Prüfverfahren 3.7.3 Versuchsergebnisse 3.8 Konstruktive Anforderungen der Endarmaturen 3.9 Analytische Berechnungsmethoden 3.9.1 Einfache analytische Methode 3.9.2 Fortgeschrittene analytische Methode 3.9.2.1 Radiale Druckspannung an der Öffnung der Metallarmatur 3.9.2.2 Axialspannung im GFK-Stab innerhalb der Metallarmatur 3.9.2.3 Schubspannung in der neutralen Achse des Stabes 3.10 Numerische Simulation 3.10.1 Finite Elemente Modell 3.10.2 Versuchsanordnung 3.11 Das Versagensverhalten von Verbundstützisolatoren 3.12 Sensitivitätsanalyse 3.13 Formelzeichen und Abkürzungen 4 Isoliertraversen für Kompaktleitungen 4.1 Einleitung 4.2 Grundsätze der Kompaktierung 4.2.1 Einfluss der Seilaufhängung auf das Mastbild 4.2.2 Möglichkeiten der Leitungskompaktierung 4.2.2.1 V-Ketten 4.2.2.2 Leitungsstützer (horizontal) 4.2.2.3 Abgehängter Leitungsstützer 4.2.2.4 Isoliertraverse 4.3 Die mechanische Auslegung von Isoliertraversen 4.3.1 Die starr gelagerte Isoliertraverse 4.3.2 Die gelenkig gelagerte Isoliertraverse (horizontal-V) 4.3.3 Dynamische Belastungen 4.3.4 Stabilitätsuntersuchungen 4.4 Innovative Anwendungen von Kompaktleitungen 4.4.1 420 kV Leitung mit Hohlkörperisolatoren in der Schweiz 4.4.2 Notgestänge mit Verbundisolatoren 4.4.3 Erste 420 kV Doppelleitung mit Volkernverbundtraversen 4.5 Formelzeichen und Abkürzungen 5 Phasenabstandshalter 5.1 Einleitung 5.2 CIGRE Umfrage 5.2.1 Auswertung Fragebogen 5.2.2 Betriebserfahrungen 5.3 Anschlusstechnik 5.4 Mechanische Auslegung von Phasenabstandshaltern 5.4.1 Galloping 5.4.1.1 Galloping Amplituden 5.4.1.2 Bauweisen 5.4.1.3 Einbauempfehlungen 5.4.1.4 Belastungen der PAH durch Galloping 5.4.2 Abwurf von Eislasten 5.4.2.1 Stosskräfte auf die PAH . 5.4.3 Elektrodynamische Kurzschlusskräfte 5.4.4 Das Knickverhalten von Phasenabstandshaltern 5.5 Elektrische Auslegung von Phasenabstandshaltern 5.5.1 Mindestlänge 5.5.2 Koronaeffekte 5.5.3 Verschmutzung 5.6 Anwendungen 5.6.1 Kompaktleitung für Mittelspannung 5.6.2 Phasenabstandshalter gegen Seiltanzen durch Eisabwurf 5.6.3 Der Tennisschlägermast 5.7 Formelzeichen und Abkürzungen 6 Ausblick 7 Anhang IEC Normen betreffend Verbundisolatoren 8 Quellenverzeichnis. / This work is the result of more than 35 years of experience with high-voltage overhead lines, 25 years of which have been devoted to silicone composite insulators. Composite insulators are nowadays regarded as an equivalent alternative to porcelain and glass insulators and are used worldwide in large quantities. Due to the diverse properties of the individual insulator components, the interaction between mechanical and electrical integrity in a composite insulator is of paramount importance. For example, cracks in the glass fiber reinforced core, caused by poor mechanical design, can lead to partial discharges and in the worst case to a catastrophic internal electrical breakdown ('flashunder'). In this sense this publication examines, after a short introduction, the different types of composite insulators, i.e. composite long rods, composite posts, insulating cross-arms for compact lines and phase-to-phase spacers; for the latter a new mechanical design concept considering large deflection theory is presented here for the first time.:1 Einleitung 1.1 Vorteile und Entwicklung von Verbundisolatoren 1.2 Erfahrungen mit Verbundisolatoren 1.3 Einsatz von Verbundisolatoren in Hochspannungsfreileitungen 1.4 Einsatz von Verbundisolatoren bei elektrischen Apparaten und Freiluftschaltanlagen. 1.5 Stand der Normung 2 Verbundlangstabisolatoren 2.1 Anwendungen von Verbundlangstabisolatoren 2.2 Das Verhalten von Verbundlangstabisolatoren unter mechanischer Beanspruchung 2.2.1 Die Dauerstandfestigkeit von Verbundlangstabisolatoren 2.2.1.1 Die Dauerkraftkurve von Verbundisolatoren nach IEC 61109/92 2.2.1.2 Mechanisches Modell für das Langzeitverhalten von Verbundisolatoren 2.3 Verhalten von Verbundlangstabisolatoren bei dynamischer Belastung 2.4 Auslegung und Montage von Endarmaturen für Verbundlangstäbe 2.4.1 Entwicklung und Stand der Technik der Metallarmaturen 2.4.2 Grundsätzliche Überlegungen zu der Auslegung von Pressarmaturen 2.4.3 Montagetechnik von Pressarmaturen 2.4.4 Berechnungssystematik 2.4.5 Einfache analytische Methode 2.4.6 Fortgeschrittene analytische Methode 2.4.6.1 Verpressung 2.4.6.2 Relaxation 2.4.6.3 Zugbelastung/Pull-out 2.4.7 Numerische Simulation 2.4.7.1 Finite Elemente Modell 2.4.7.2 Rechenergebnisse der Simulation 2.4.7.3 Ergebnisse der numerischen Versagenssimulation 2.4.7.4 Versuchsergebnisse 2.4.7.5 Sensitivitätsanalyse 2.5 Formelzeichen und Abkürzungen 3 Verbundstützisolatoren 3.1 Wesentliche Eigenschaften 3.2 Anwendungen von Verbundstützisolatoren 3.3 Das Verhalten von Verbundstützisolatoren unter Biegung 3.3.1 Allgemeines 3.3.2 Einführung einer Schadensgrenze (damage limit) 3.3.2.1 Versuche zur Bestimmung der Schadensgrenze 3.3.2.2 Versuch zur Bestimmung der maximalen Betriebsbiegelast (MDCL) 3.3.2.3 Bestimmung der MDCL und der SCL im gleichen Versuch 3.4 Herstellerangaben zum SCL/MDCL Konzept 3.5 Das sichere Verhalten beim Versagen von Verbundstützern (safe failure mode) 3.6 Kombinierte Belastungen 3.6.1 Lastdiagramme 3.6.2 Beispiele 3.6.2.1 Horizontale Lage des Isolators 3.6.2.2 Isolator bildet einen Winkel von β = 15° zur Horizontalen 3.6.3 Computersimulation 3.6.4 Versuche 3.7 Dynamische Belastungen 3.7.1 Prüflinge 3.7.2 Prüfverfahren 3.7.3 Versuchsergebnisse 3.8 Konstruktive Anforderungen der Endarmaturen 3.9 Analytische Berechnungsmethoden 3.9.1 Einfache analytische Methode 3.9.2 Fortgeschrittene analytische Methode 3.9.2.1 Radiale Druckspannung an der Öffnung der Metallarmatur 3.9.2.2 Axialspannung im GFK-Stab innerhalb der Metallarmatur 3.9.2.3 Schubspannung in der neutralen Achse des Stabes 3.10 Numerische Simulation 3.10.1 Finite Elemente Modell 3.10.2 Versuchsanordnung 3.11 Das Versagensverhalten von Verbundstützisolatoren 3.12 Sensitivitätsanalyse 3.13 Formelzeichen und Abkürzungen 4 Isoliertraversen für Kompaktleitungen 4.1 Einleitung 4.2 Grundsätze der Kompaktierung 4.2.1 Einfluss der Seilaufhängung auf das Mastbild 4.2.2 Möglichkeiten der Leitungskompaktierung 4.2.2.1 V-Ketten 4.2.2.2 Leitungsstützer (horizontal) 4.2.2.3 Abgehängter Leitungsstützer 4.2.2.4 Isoliertraverse 4.3 Die mechanische Auslegung von Isoliertraversen 4.3.1 Die starr gelagerte Isoliertraverse 4.3.2 Die gelenkig gelagerte Isoliertraverse (horizontal-V) 4.3.3 Dynamische Belastungen 4.3.4 Stabilitätsuntersuchungen 4.4 Innovative Anwendungen von Kompaktleitungen 4.4.1 420 kV Leitung mit Hohlkörperisolatoren in der Schweiz 4.4.2 Notgestänge mit Verbundisolatoren 4.4.3 Erste 420 kV Doppelleitung mit Volkernverbundtraversen 4.5 Formelzeichen und Abkürzungen 5 Phasenabstandshalter 5.1 Einleitung 5.2 CIGRE Umfrage 5.2.1 Auswertung Fragebogen 5.2.2 Betriebserfahrungen 5.3 Anschlusstechnik 5.4 Mechanische Auslegung von Phasenabstandshaltern 5.4.1 Galloping 5.4.1.1 Galloping Amplituden 5.4.1.2 Bauweisen 5.4.1.3 Einbauempfehlungen 5.4.1.4 Belastungen der PAH durch Galloping 5.4.2 Abwurf von Eislasten 5.4.2.1 Stosskräfte auf die PAH . 5.4.3 Elektrodynamische Kurzschlusskräfte 5.4.4 Das Knickverhalten von Phasenabstandshaltern 5.5 Elektrische Auslegung von Phasenabstandshaltern 5.5.1 Mindestlänge 5.5.2 Koronaeffekte 5.5.3 Verschmutzung 5.6 Anwendungen 5.6.1 Kompaktleitung für Mittelspannung 5.6.2 Phasenabstandshalter gegen Seiltanzen durch Eisabwurf 5.6.3 Der Tennisschlägermast 5.7 Formelzeichen und Abkürzungen 6 Ausblick 7 Anhang IEC Normen betreffend Verbundisolatoren 8 Quellenverzeichnis.

Cette thèse traite de la conception et mise en œuvre d’espaceurs auto-effondrables novateurs pour une utilisation dans des sondes d’activité enzymatique in vivo.La première partie détaille la synthèse et la validation in vitro d’espaceurs cyclisant, couplant l’activité d’un aminopeptidase à la libération d’un phénol. Les sondes fluorogènes modulaires basées sur ces espaceurs 1,2-diamine sont très robustes (demi-vie > 560 h), mais sont rapidement enzymatiquement hydrolysées, et puis relâchent rapidement (demi-temps ~ 3 min) un fluorophore ESIPT insoluble et exceptionnellement photostable.Ces sondes ont une excellente sensibilité (rapport signal:contrôle > 3000:1), et fournissent la première démonstration d’un système macroscopiquement binaire éteint–ALLUMÉ, pour la libération de phénols sous activité d’aminopeptidases. Ce système pourrait permettre de faire de l’imagerie moléculaire ultra-sensible d’une gamme d’exopeptidases. Ces espaceurs pourraient également servir dans des sondes comportant d’autres fluorophores phénoliques, dans des promédicaments de phénols/alcools activés par des peptidases spécifiques (thérapies ciblées), ou comme adaptateurs chimiques en générale.La deuxième partie détaille les synthèses de deux familles d’espaceurs tautomérisant/éliminant pour utilisation dans des sondes magnétogènes d’activité de glycosidases. Les premières architectures substrat-espaceur basées sur des 2-furanols et des carbimidates cycliques ont été explorées. Notamment, des glycosides 2-furanoliques ont été abordés comme espaceurs énergétiques alternatifs aux quinone méthydes, et des carbimidates ont été explorés comme espaceurs pour ligands modèles des sondes promagnétiques. / This thesis concerns the design and implementation of novel auto-immolative spacers for use in probes for enzymatic activity in vivo.The first part relates the development and in vitro validation of cyclisation spacers which couple the action of an aminopeptidase to the release of a phenol. The modular three-component fluorogenic probes based on these 1,2-diamine spacers are very robust (halflife > 560 h), but are also rapidly enzymatically processed, and quickly (halftime ~3 min) release an exceptionally photostable, insoluble ESIPT fluorophore. The probes have excellent detection sensitivity relative to current methods (signal to control ratio > 3000:1), and provide the first demonstration of a macroscopically binary off–ON system for phenol-releasing probes of aminopeptidase activity. The probe system may allow the exceptionally sensitive, ESIPT-based molecular imaging of a range of exopeptidases. The spacers may also be applied in off ON peptidase probes of other phenolic fluorophores, to peptidase-specific phenol/alcohol prodrugs for targeted therapy, or more generally in chemical adapter technologies.In the second part, two novel families of auto-immolative elimination/tautomerisation spacers were designed for use in three-component off ON magnetogenic probes sensing glycosidase activity. The first known substrate-spacer designs based on 2-hydroxyfurans and on carbimidates were explored. Notably, 2 furanol glycosides were synthesised in pursuit of high-energy alternatives to quinone methides, and a general method for preparing model carbimidate-bearing ligands for pro-magnetic probes was elaborated.

Different monomeric diols, with a central rigid FD unit connected with two aliphatic chains of various length, were prepared to react with aromatic mesogenic triad, TOBC. In this manner, thermotropic polyesters with possible low thermal transition temperatures (including Tmand Ti) and high solubility in organic solvent can be generated in view of the non-linear polymeric chain imposed by the rigid, bent FD moieties. In addition to the effect of the aliphatic chain length, polyesters of different molecular weight will be obtained by different synthesis approach (or fractionation of the resulting polyester product) and therefore, the influence of molecular weight on liquid crystalline properties can be evaluated.