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Chandrasekaran, Arvind. "Effect of encapsulant on high-temperature reliability of the gold wirebond-aluminum bondpad interface." College Park, Md. : University of Maryland, 2003. http://hdl.handle.net/1903/281.
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Thesis (M.S.) -- University of Maryland, College Park, 2003.Thesis research directed by: Dept. of Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Mohd-Shariff, M. H. B. "Analysis of finite deformation of bonded and non-bonded rubber mountings." Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355075.
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Baggerman, Jacob. "Photoactive hydrogen-bonded rotaxanes." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2006. http://dare.uva.nl/document/23505.
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Willis, Kimberly. "Hydrogen-bonded liquid crystals." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266002.
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MARTÍNEZ, OLGUÍN GEMA JURIE. "Análisis comparativo de los rendimientos sectoriales de la BMV y de BIVA a través de las técnicas Logit y VaR, 2018." Tesis de Licenciatura, UNIVERSIDAD AUTONOMA DEL ESTADO DE MEXICO, 2020. http://hdl.handle.net/20.500.11799/109149.
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Como soporte, para poder cumplir con dichos objetivos, el trabajo de investigación se divide en cuatro capítulos:
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• Capítulo I: Proporciona una recopilación de artículos, papers y journals acerca de cómo otros autores han trabajado y analizado casos y temas relacionados al de la presente investigación. De igual manera, se da una descripción de los ejes centrales del trabajo, para un mejor entendimiento de lo que trata el proyecto. • Capítulo II: En este apartado, se provee una introducción del Sistema Financiero Mexicano, cuáles son sus componentes y cómo funciona; de igual manera dicha sección habla acerca de la Bolsa Mexicana de Valores y de algunas de sus características tales como objetivo, funcionamiento, índice, entre otras. Así mismo, se discute la creación de BIVA, cómo y por qué surge una nueva bolsa de valores, cuáles son los beneficios directos e indirectos y cuál será su funcionamiento. Finalmente se hace una comparación entre bolsas en cuanto a sus propiedades (emisoras, índices, etc.). • Capítulo III: Una vez que se ha establecido la importancia de las variables de estudio, en el capítulo tres se procede a explicar en qué consiste el modelo en general, empezando por el tipo de variables, seguido por el tipo de estudio y las técnicas que se utilizan para llevar a cabo la investigación, que son: el modelo multivariable Logit y el modelo del valor VaR. • Capítulo IV: Por último, en este capítulo se da la explicación de la elaboración del modelo, se ponen en práctica todos los conocimientos previamente explicados, para hacer la comparación de los rendimientos y el valor en riesgo de cada uno de los sectores de las variables de estudio, BIVA y BMV.
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Sarmiento, Eljadue Nataly. "¿Bondad o estrategia? tejiendo responsibilidad social en el mundo del carbón /." Bogotá, D.C., Colombia : Universidad de los Andes, Facultad de Ciencias Sociales-Ceso, Departamento de Ciencia Política, 2008. http://catalog.hathitrust.org/api/volumes/oclc/390710419.html.
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Bressani, Luiz Antonio. "Experimental properties of bonded soils." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/7538.
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Al-Jazairy, Yousra H. "Microleakage of bonded amalgam restorations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq23196.pdf.
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Miller, Tad W. "Modified intermetallic-bonded diamond composites /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1136092311&sid=16&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Thesis (M.S.)--Southern Illinois University Carbondale, 2006."Department of Mechanical Engineering and Energy Processes." Includes bibliographical references (leaves 99-102). Also available online.
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Piermattei, Alessio. "Liquid crystalline hydrogen-bonded rosettes." Enschede : University of Twente [Host], 2007. http://doc.utwente.nl/57859.
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Singh, Surendra Kumar. "Bonded labour and the law /." New Delhi : Deep & Deep, 1994. http://www.gbv.de/dms/spk/sbb/recht/toc/278125786.pdf.
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Wood, Ian. "Hydrogen bonded double helical macrocycles." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285635.
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Sidambe, Alfred Twala. "Surface engineered polymer bonded magnets." Thesis, Cranfield University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427154.
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Huff, Michael Allan. "Silicon micromachined wafer-bonded valves." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12727.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1993.Includes bibliographical references (v. 2, leaves 429-436).
by Michael Allan Huff.
Ph.D.
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Pérez, Emilio M. "Hydrogen-bonded synthetic molecular machines." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/15610.
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This thesis reports on: 1) the development of two new methods to provoke the translation of the macrocycle along the thread (“shuttling”) in hydrogen bonded, fumaramide-based [2]rotaxanes and 2) the utilization of that movement to provoke a potentially useful response. The fumaramide template is perfectly preorganised to form four intercomponent hydrogen bonds with a benzylic amide macrocycle, affording [2]rotaxanes in “world record” yields. This preorganisation can be disrupted by photo-isomerisation (254 nm) of the E double bond to its Z counterpart. The newly formed maleamide template shows little affinity for the macrocycle. This has previously been exploited to synthesise a light and heat switchable molecular shuttles. A unique tristable molecular shuttle in which the macrocycle can be located in three different “stations” by means of thermal and photochemical stimuli is described in Chapter Two. In Chapter Three an alternative mechanism of shuttling for fumaramide-based molecular shuttles is reported. The reversibility of Diels-Alder chemistry is exploited to synthesise a chemically driven molecular shuttle. A chiral two-station [2]rotaxane in which translational motion of the macrocycle along the thread results in a profound change in its optical properties (CD spectrum) is described in Chapter Four. Finally, a light-switchable optically-addressable molecular shuttle is discussed. A [2]rotaxane with a thread containing a fluorophore and a macrocycle functionalised to quench its fluorescence was synthesised. Shuttling of the macrocycle along the thread switched the fluorescence “on” and “off”.
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Skarvelas, Georgios Aristeidis. "Reinforcement and Bonded Block Modelling." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-85984.
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The objective of this master’s thesis is to evaluate the use of Bonded Block Modelling (BBM) in 3DEC software combined with hybrid rock bolts, for three different cases. These cases included the laboratory rock bolt case, the shearing case and the blocky rock mass case. 3DEC is a Distinct Element Method (DEM) numerical software which can be used to simulate both continuum and discontinuum media in 3D. The Bonded Block Model in 3DEC can be used to simulate a rock mass as bonded polyhedral elements. The BBM is a relatively new numerical modelling technique. Earlier studies have focused mainly on laboratory test cases and less on field scale studies. The laboratory rock bolt test was introduced by Hoek and the main idea was to describe the way that rock bolts work. Four different rock bolt spacing designs were simulated and one unsupported model, in order to validate Hoek’s results. The diameter of the blocks was 15 cm while the zones were modelled with length of 5 cm. The tunnel on the shearing case was excavated at the depth of 1500 m. For the stress field, the in-situ stresses of Kiirunavaara mine were considered. The tunnel on the blocky case was excavated at the depth of 30 m and a gravitational stress field was assumed. The shearing model as well as the blocky model, were simulated on a quasi-3D model. The zone length for both cases was 0.1 m. In both cases, a discontinuum non-BBM was modelled first and then, a discontinuum BBM with different rock UCS values was simulated. The discontinuum BBM on the shearing case was simulated for rock UCS of 200, 100, and 50 MPa, while on the blocky case, it was simulated for rock UCS of 50 MPa. The Mohr – Coulomb constitutive model was selected for all three modelling cases. The conclusions of this work were the following: – The laboratory rock bolt model validated the results of Hoek. Hoek suggested that rock bolt spacing less than three times the average rock piece diameter would be sufficient to produce positive results. The stabilization of the rock pieces as well as the forming of the compression zone were achieved when this equation was satisfied. The geometry of the stabilized material as well as the compression zone, were also correct. – The discontinuum BBM on the shearing case with intact rock UCS of 200 MPa, produced similar results as the discontinuum non-BBM. This indicates that BBM can be applied for these cases and produce reliable results. The displacement of the fault was expected to be higher than the resulting values. The discontinuum BBM with reduced rock strength (100 MPa and 50 MPa) resulted in rock mass fragmentation. However, the fragmented rock pieces did not detach from the rock mass as the displacement values were not high enough. – The discontinuum BBM on the blocky case with intact rock UCS of 50 MPa, produced similar results as the discontinuum non-BBM. There were two discontinuities that affected the smooth transition of the displacement/stress results on the different blocks. The fragmentation of the rock mass due to the existence of the discontinuities did not produce any further rock mass movements. – The interaction between rock mass and rock bolts was evident in any modelling case. For the laboratory rock bolt model, the hybrid bolts design was vital for producing correct results. For the shearing model, the hybrid bolts were subjected to shearing movements due to fault movements. In the blocky model, the bolts in the roof of the tunnel were subjected to axial displacements, due to the existence of blocks. The recommendations for further work were the following: – The hybrid bolts in the laboratory rock bolt test were pretensioned only in the beginning of the computation phase. In reality, the tensioned bolts act at every moment and not only in the beginning. However, it would be interesting to see if the results are similar with continuously tensioned hybrid bolts. It is anticipated that the constantly tensioned hybrid bolts should be able to keep the compressive zones with high values throughout the whole cycling process. Thus, it is suggested for future modellers that this case could be modelled with continuously tensioned hybrid bolts. – The installation of rock bolts in the shear case as well as in the blocky case, was at the exact same time as the tunnel was excavated. This is not realistic fact because it is impossible to install the rock bolts exactly the same time as the tunnel excavated. Thus, it is suggested that those two cases could be modelled in the future with more focus on the stress relaxation factor.
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Budzik, Michal. "Fracture in asymmetric bonded joints." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14041/document.
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Des tests de fissuration ont été réalisés sur des joints collés asymétriques. Ces assemblages asymétriques sont constitués de deux substrats de nature et/ou d’épaisseur différentes liés par un adhésif. Cette géométrie d’éprouvette semble peu utilisée pour effectuer des essais de fissuration. Elles présentent certains inconvénients et de ce fait n’ont fait l’objet d’aucune normalisation. Dans le cadre cette géométrie d’éprouvette d’essai a été néanmoins été retenue et utilisée dans trois configurations différentes pour la caractérisation mécanique des assemblages collés. Des protocoles d’essai et les schéma d’analyse associés ont été définis pour des essais de fissuration à vitesse de déplacement imposé (CRT : Constant Rate Test), à force imposée (CFT : Constant Force Test) ainsi qu’à déplacement imposé (CDT : Constant Displacement Test). Les analyses ont pu être étalonnées au moyen d’un étau matérialisant artificiellement la position d’un fissure. De nombreuses configurations ont été étudiées à l’occasion de ce travail tant du point de vue des adhésifs utilisés (epoxy, cyanoacrylate, acrylic mastic, PSA) que du point de vue des substrats encollés (alliage d’aluminium, composite à matrice organique, polycarbonate). Ces nouveaux tests s’avèrent prometteurs car ils permettent de suivre de façon continu et précision la propagation de fissure au sein de la liaison. En outre, l’analyse des déformations mesurées par extensométrie lors d’essai réalisés à déplacement imposé (CDT) permet un suivi précis de la réponse de la couche adhésive dans la zone contrainte et d’estimer la taille de cette dernière, y compris lorsque la colle est dans un état métastable. Un autre résultat important de ce travail concerne l’analyse de la modification du front de fissure celle-ci voit une diminution de l’adhésion entre les deux substrats. Enfin, un calcul plus précis du taux de restitution d’énergie a été proposé pour prendre en compte le caractère élastique de la couche adhésive, mais permettant aussi de mieux appréhender la redistribution des contraintes dans la colle, et ainsi mieux interpréter les essais mécaniques réalisés. Des analyses par Microscopie à Force Atomique (AFM) ainsi qu’au microscope électronique à balayage (MEB) ont été effectués sur les substrats encollés pour évaluer l’impact des traitements de surface. Des simulations numériques par la method des éléments finis ont été réalisées pour determiner l’état de contrainte dans nos éprouvette d’essai et ainsi expliquer la courbure du front de fissure et les faciès de rupture observés. Les nouvelles configurations expérimentales décrites dans ce manuscript nous paraissent prometteuses car elle offrent une amelioration très significative en terme de fiabilité et précision comparativement aux tests présentés habituellement pour ce type de travauxAdhesion was studied in asymmetric bonded joints using fracture mechanics tests. The asymmetric bonded joints consist of two different type and/or thickness materials bonded by an adhesive. Mentions of asymmetric bonded joint tests employed so far are rare in the literature. They are imperfect and therefore are not standardized. Accordingly three new tests were introduced in this work to study bonded joints. The new metrological routines and models were built for the CRT (Constant Rate Test), CFT (Constant Force Test) and the CDT (Constant Displacement Test). The routines were validated with the new Artificial Crack Tip test developed in this thesis. Different bonded systems were examined: the adhesives - epoxy, cyanoacrylate, acrylic mastic, PSA; the bonded adherends - aluminium alloys, CFRP composites and polycarbonate. The results obtained in the new tests are very promising in terms of the accuracy and continuous observation of crack kinetics. In addition it was found that the novel strain gauge technique, introduced in the CDT, test allows precise joint monitoring when the adhesive is in a metastable state and a precise estimation of process zone. Another interesting achievement of this work was describing the phenomenon of double crack curvature in the vicinity of the strong – weak adhesion transition zone. The next achievement was derivation of the strain energy release rate from the elastic foundation model, which gives better understanding of the mechanics and the measurements behind adhesive bonding. Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM) studies were made of the bonded substrates to estimate the surface treatment effects. The stress state in asymmetric geometry was studied using finite element analysis (FEA), which explained the formation of the curved crack front and the origin of river patterns. The new tests developed in this study appear promising since they offer accurate and reliable results for the materials tested
W pracy przedstawiono wyniki badan asymetrycznych zlaczy adhezyjnych z wykorzystaniem prób mechaniki pekania. Asymetryczne zlacza klejone powstaja przez polaczenie dwóch dowolnych materialów, o innym wskazniku na zginanie, za pomoca kleju. Zaproponowano trzy nowe metody eksperymentalne dla których zaprojektowano i zbudowano stanowiska badawcze. Poprawnosc modeli fizycznych i matematycznych wykorzystanych do interpretacji badanych zjawisk potwierdzono wykorzystujac opracowana w pracy próbe ze sztucznym frontem pekniecia. Próby przeprowadzono na zlaczach klejonych wykorzystujac kleje: epoksydowe, cjanoakrylowy, typu Mastic i PSA, laczonymi materialami byly: stopy aluminium, kompozyt weglowy oraz poliweglan. Wyniki badan uzyskane przy wykorzystaniu nowych metod wskazuja na ich pewnosc i dokladnosc, dodatkowo umozliwiaja ciagla obserwacje propagujacego pekniecia. Nowa metoda pomiaru parametrów mechaniki pekania oparta na pomiarach tensometrycznych zostala z powodzeniem zastosowana do zlaczy w których klej znajduje sie w stanie metastabilnym. W pracy zaobserwowano i przeanalizowano zjawisko powstawania podwójnego frontu pekniecia na granicy osrodków o róznych silach adhezji, dotad nie opisanego. Po raz pierwszy wyprowadzono równanie szybkosci uwalniania energii sprezystej wykorzystujac model belki na sprezystym podlozu, co umozliwia lepsze zrozumienie zachowania sie zlaczy klejonych. Przeprowadzone badania z uzyciem mikroskopii sil atomowych (AFM) oraz skaningowej mikroskopii elektronowej (SEM) umozliwily ocene efektów obróbki powierzchniowej stopów aluminium. W pracy dokonano analizy naprezen w asymetrycznych zlaczach adhezyjnych z wykorzystaniem metody elementów skonczonych (FEM). Analiza FEM pozwolila na wyjasnienie zjawiska powstawania zakrzywionego frontu pekniecia w badanych przelomach. Zaproponowane nowe metody badan zlaczy asymetrycznych zapewniaja dokladnosc i pewnosc pomiaru dla materialów wykorzystanych w badaniach
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Cheek, Douglas William. "Internally Hydrogen-Bonded PRODAN Derivatives." W&M ScholarWorks, 2015. https://scholarworks.wm.edu/etd/1539626962.
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Knox, Esther M. "Marine applications for structural adhesives." Thesis, University of Glasgow, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241876.
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Armstrong, Gordon Smith. "High frequency dielectric evaluation of water and solvent aged adhesive joints." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248830.
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Otto, Franciele. "As associações auxiliares da escola e a forma de transmissão das dimensões valorativa e moral da sociedade catarinense: o caso das \"Ligas de Bondade\" (1935-1950)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/48/48134/tde-12062012-140719/.
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A investigação histórica que compõe a presente dissertação parte das relações entre o ideário escolanovista e as propostas de nacionalização do ensino aplicadas no Estado de Santa Catarina, a partir da década de 30 do século passado. Estas constituíram as bases para o surgimento das Associações Auxiliares da Escola, dentre as quais existiu a Liga de Bondade. De uma forma geral, o objetivo desta investigação foi identificar, descrever e interpretar a transmissão das dimensões morais por meio das Ligas de Bondade. Para cumprir tal objetivo, utilizaram-se como fontes de informação, além da legislação da época, 142 relatórios e atas das reuniões destas ligas que foram enviadas ao Departamento de Educação do Estado de Santa Catarina, armazenados no Arquivo Histórico do Estado de Santa Catarina. O conceito de cultura escolar foi utilizado para localizar o lugar das Ligas de Bondade como práticas escolares, e foram analisados alguns Regulamentos da Instrução Pública e Regimentos Internos dos Grupos Escolares para compreender como estavam presentes nestas determinações estatais as premissas morais difundidas por estes grupos. Esta prática pode ser observada de diferentes perspectivas, pois foram vários os aspectos que formaram o cotidiano e as atividades realizadas. Algumas das atividades identificadas foram: reuniões, eleições, festas escolares, palestras, caixinha das boas ações, campanhas, doação de esmolas, tratamento de enfermos, doação de alimentos, homenagens. As Ligas de Bondade utilizaram diversos métodos para a transmissão moral que pretendiam realizar, como as lições temáticas; prática de boas ações; participação na Campanha Pró-Natal dos Lázaros; slogans e imagens. Identificou-se que a noção de bondade comportava várias dimensões, que eram: solidariedade, cuidado com o semelhante, caridade, honestidade, respeito, cuidado com o patrimônio público, cooperação, responsabilidade, amor à pátria, gratidão e fé. Estes valores difundidos moldavam as disposições das crianças para as respostas sociais que necessitariam no futuro, determinando as condutas corretas e influenciando a formação do habitus. O conceito de habitus faz parte da teoria da prática de Pierre Bourdieu, e permitiu compreender a forma como os valores atingiam os alunos. As disposições (habitus) dos sócios das Ligas de Bondade passaram a ser uniformizadas, formando uma consciência coletiva, que homogeneizava as virtudes morais dos participantes. A consciência coletiva (Émile Durkheim) tornava os valores sociais a partir da produção de um consenso entre os alunos. Esta pesquisa demonstrou o funcionamento das Ligas de Bondade - pautada nas informações encontradas nos relatórios e atas catarinenses, e nas instruções de funcionamento estabelecidas na legislação educacional e os meios utilizados para a difusão dos valores morais entre seus sócios. O estudo das Ligas de Bondade permitiu compreender aspectos das transmissões morais realizadas pelas escolas, transportando situações sociais para dentro dos estabelecimentos. Além disso, reconstituiu o cotidiano destas Associações Auxiliares do ponto de vista dos documentos oficiais.The historical research that is part of this thesis starts from the relationships between the New School ideas and the proposals for the nationalization of education applied in the State of Santa Catarina, since the 1930s. They formed the basis for the creation of the Associações Auxiliares da Escola (school auxiliary associations) among which, the Ligas da Bondade (goodness leagues). The present study aimed at identifying, describing, and interpreting the transmission of the moral dimensions through the Ligas da Bondade. To this end, a hundred and forty two meeting reports and minutes of those leagues/associations which have been sent to the Departamento de Educação do Estado de Santa Catarina, stored in the Arquivo Histórico do Estado de Santa Catarina (the historical archives of SC) were used as sources of information, besides the laws of that period. The concept of school culture was used to locate the place of the Ligas da Bondade as school practices, and some of the public instruction regulations and internal regulations of the school groups were analyzed in order to understand how the moral premises propagated by these groups were present in the referred state determinations. This practice can be observed from different perspectives, because many were the aspects that formed the everyday activities. Some of the identified activities were: meetings, elections, school parties, lectures, good deeds box, campaigns, almsgiving, treatment of the sick, food donation, tributes. The Ligas da Bondade used several methods for the moral transmission that they intended to hold, as the thematic lessons, good deeds practices, participation in the Lazarus Pro-Christmas Campaign, slogans and images. It was found that the idea of goodness contained several dimensions, which were: solidarity, care for other people, charity, honesty, respect, care for public properties, cooperation, responsibility, love for the country, gratitude and faith. The referred values shaped the children\'s dispositions for the social responses they would need in their future, determining the correct behavior and influencing the formation of the habitus. The concept of habitus is part of Pierre Bourdieu\'s practice theory, and enabled the understanding of the way in which the values reached the students. The dispositions (habitus) of the Ligas da Bondades members became uniform, forming a collective consciousness, which made the participants\' moral virtues homogeneous. The collective consciousness (Émile Durkheim) made the social values from the production of a consensus among the students. This study demonstrated how the Ligas da Bondade work - based on information found in the meetings reports and minutes from Santa Catarina, and in the operating instructions set out in the educational laws - and the means used to disseminate the moral values among its members. The study of the Ligas da Bondade enabled the understanding of the aspects of the moral transmissions accomplished by the schools, transporting social situations into the establishments. Additionally, this study strengthened the daily life of the referred auxiliary associations from the viewpoint of the official documents.
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Yiu, Kar-yung Cynthia. "Fluid transport across bonded dentin interfaces." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36841201.
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Moulin, Silva Wagner. "Microsilica-bonded magnesia-based refractory castables." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-77492.
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Among the most impressive developments observed in the last 20 years, the improvement of the installation methods of monolithic refractories is certainly to be taken into account. However, this evolution, from vibratable castables to shotcrete and drycrete was not applied to materials based on magnesia, which are still mostly commercialized as ramming mixes, or as pouring castables with poor properties due to excessive water use. The major issues associated to this lack of technology is the scarcity of submicrometric powders compatible to magnesian systems, and the expansion followed by hydration of the magnesia, which is a disruptive reaction.
By a thorough research on the literature, some potential additives were identified to be tested as anti-hydration additives. Hydration tests of powders in autoclave, complemented by pH and rheological measurements on magnesia pastes have identified five possible additives which can be used to inhibit the hydration: tartaric acid, citric acid, boric acid, magnesium fluoride and microsilica. Salts from the organic acids can also be successfully used. Of these, microsilica also presented the advantage of providing the submicrometric particles necessary to improve the flow of the castable, and to improve the bond of the castable. The three acids are very effective in inhibiting the formation of magnesium hydroxide, but affect negatively flow properties and mechanical resistance after cure.
Microsilica prevented hydration cracks due to the reaction between the silicic acid generated under basic environment with the newly formed brucite, leading to the precipitation of a magnesium-silica-hydrated phase of poor crystallinity between the magnesia grains. This phase does not promote volumetric change, and also enable water release at a wider temperature range. Due to its nature close to serpentine minerals, it forms forsterite and enstatite at low temperatures, thus generating suitable strength between room temperature and at least 1400 °C.
Magnesium fluoride changed the nature of this magnesium-silica-hydrated phase, by being incorporated to it and forming a phase more similar to the humite minerals. These minerals present higher MgO:SiO2 molar ratio than serpentine, and their formation requires a lower content of microsilica for a same effect against hydration, which is beneficial for the overall properties of the castable.
The properties of the castable, as well as the influence of a number of other variables (for instance, refractoriness under load, creep, cold crushing strength, cold modulus of rupture, bulk density and apparent porosity) were also studied and hereby reported. It is believed that this technology can be further developed for industrial use, provided that some issues regarding the properties at high temperatures are solved. Not only had the study and comprehension of the nature of the bond between microsilica and magnesia, and the role of magnesium fluoride been pioneered by this work, but also the methodology used to evaluate the hydration after the drying process of castings, which was close to real refractory components.
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Schmidt, Peter. "Computational Models of Adhesively Bonded Joints." Doctoral thesis, Linköping : Division of Mechanics, Department of Management and Engineering, Linköping University, 2007. http://www.bibl.liu.se/liupubl/disp/disp2007/tek1076s.pdf.
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Cavalleri, Matteo. "Local Structure of Hydrogen-Bonded Liquids." Doctoral thesis, Stockholm : Fysikum, Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-286.
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Butkus, Lawrence M. "Environmental durability of adhesively bonded joints." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/19008.
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Yiu, Kar-yung Cynthia, and 姚嘉榕. "Fluid transport across bonded dentin interfaces." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36841201.
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Ziada, Hassan M. A/R. "Photoelastic stress analysis in bonded bridges." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334493.
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Davey, James Brian. "Microwave spectroscopy of halogen-bonded complexes." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249075.
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McConnell, Barry Kerr. "Dielectric studies of adhesively bonded structures." Thesis, University of Strathclyde, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426326.
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Clark, Stewart. "Complex structures in tetrahedrally bonded semiconductors." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/13420.
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Complex tetrahedral structures form good models for amorphous Group IV and III-V semiconductors. With a view of working towards examining non-crystalline materials, the structural, electronic and vibrational properties of complex tetrahedrally bonded semiconductors are investigated by various molecular dynamics techniques. First principles quantum mechanical molecular dynamics calculations are performed on two such structures and the effects of pressure on their behaviour is reported. A full free energy calculation using this method remains unfeasible and therefore an empirical bond charge model is used to calculate the full pressure-temperature phase diagram of the structures. Several surface reconstructions of a complex phase of silicon are then examined and the lowest energy surface of any silicon structure so far is found. Point defects in the diamond phase of silicon and carbon also give insight into various unusual bonding topologies that could be found in their amorphous phase. Structural and vibrational properties of several defects are considered. Finally, calculations on amorphous carbon and silicon at several densities are done and a comparison between the structural and electronic properties made. New bonding topologies are found in the structures including three centre bonding orbitals in the amorphous carbon models.
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Graner, Solana Alejandro. "Fatigue initiation in adhesively bonded structures." Thesis, University of Surrey, 2008. http://epubs.surrey.ac.uk/844365/.
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The objective of this research was to find patterns of fatigue initiation in adhesively bonded structures. Fatigue initiation plays a very important role in the useful life of any structure, but it is a difficult phenomenon to quantify. Three types of aluminium-FM73M single lap joints (SLJ) were tested in tensile mode at different loads. The damage was recorded using the backface strain technique. Six strain gauges (SGs) were installed to record damage. Several types of tests were performed: tests to failure, tests to limited damage and sectioning, and tests to limited damage and a residual strength test. The tests to failure were performed to obtain backface strain patterns. The specimens tested to limited damage were sectioned, polished and inspected under a microscope to study how the damage affected the adhesive. The tests to limited damage, followed by a static test to failure, were carried out to find the effect of damage on the static strength. The load-life data obtained matched previous data well. Experimental tests found that the damage appeared in the fillet as a microcrack formation, merging at the end of the test into a major crack. This pattern depended on geometry and load. The residual strength tests in specimens with limited damage showed that the joints kept a significant proportion of original static strength, even if the joint had been damaged significantly. Numerical simulations were performed in ABAQUS to match and predict fatigue life and backface strain patterns at different loads. Fortran was used to develop damage models based on user-defined field subroutines. Two elastic damage models were developed (one and two phase), which reduced the elastic modulus as damage increased. A more complete elasto-plastic damage model was also developed. In this model the elastic modulus and yield stress were reduced. This gave good predictions of both fatigue life and backface strain patterns. This model can be used to determine fatigue lives in other bonded structures and represents an important step forward in this area.
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Masuku, Crispen. "Tensile relaxation of bonded concrete overlays." Master's thesis, University of Cape Town, 2009. http://hdl.handle.net/11427/12109.
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Includes abstract.Includes bibliographical references (leaves 131-135).
Restrained shrinkage in bonded concrete overlays can cause stress build up, cracking and even debonding. Tensile relaxation is the main mechanism of stress relief in concrete overlays. This results in less possibility of cracking and debonding. The research described in this study presents an analytical method of analysis. This method is based on tests performed to assess tensile relaxation in concretes subjected to restraint. Although this study is limited in scope, it serves as an introduction to the topic and contributes a valuable bank of results obtained. In this study, commercial repair mortar (Sika® Rep LW), 0.45 and 0.65 w/c ratio custom-made mixes were investigated. Uniaxial tensile strength, tensile elastic modulus, shrinkage and tensile relaxation tests were done on dog-bone concrete mortar specimens.
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Owen, Nicholas D. S. "The H-bonding activity of F'- with some phenols." Thesis, University of York, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280440.
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Singh, Namrata. "A Synthetic, Electronic and Theoretical study on the interaction of Quadruply bonded Molybdenum and Tungsten delta orbitals with organic pi systems in Monomeric, Dimeric and Trimeric units." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1244582769.
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Lewis, Rhobert. "Proton acceptor-proton donor interactions in gases and low temperature matrices." Thesis, University of South Wales, 1990. https://pure.southwales.ac.uk/en/studentthesis/proton-acceptorproton-donor-interactions-in-gases-and-low-temperature-matrices(bb889443-24fd-427e-b994-522a416d5988).html.
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The infrared spectra of mixtures of HC1 and the following have been recorded in the gas phase and low temperature matrices: argon, ethene, ethyne, de-benzene, fluorobenzene, CO, CO 2 , SOz, CC1*, CHCls, de-acetone, ethanal, HCN and acrylonitrile. The features which have been measured are: firstly the changes in the integrated intensity of lines in the rotation-vibration spectrum of the fundamental HC1 band as a function of interactions with other components of the mixture, and secondly bands associated with specific interactions forming hydrogen-bonded complexes. The enhancement of HC1 is generally found to vary linearly with the pressure of added gas over a limited pressure range. Assuming that line enhancement is caused by collisionally-induced rotation-translation energy exchange to or from the HC1 molecule, a combination of expressions derived from Ehrenfest's Adiabatic Principle and the "rigid rotor" approximation leads to a model which qualitatively predicts the enhancements observed. The model also rationalises the enhancement of HCN and SOa absorptions by HC1. Examination of the experimentally determined data leads to the conclusion that the total intermolecular force between the monomer base and HC1 controls the degree of enhancement but it is concluded that there is no general connection between the degree of HC1 enhancement and hydrogen-bond strength. Hydrogen-bonded complexes were examined in the gas and argon matrix phases and the shifts in the modified hydrogen chloride stretch compared for various bases. The spectra of pi-complexes formed between HC1 and ethene, ethyne and benzene were found to be detectable by low-resolution infrared spectroscopy at room temperature. Complexation of HCN, he-acetone and de-acetone with HC1 caused CN and C=O band shifts. The Chem-X molecular modelling program was evaluated by using it to predict the geometry of simple complexes for which experimental data is already available. It is concluded that the program requires more development before it can be confidently used as a theoretical aid with which to study hydrogen-bonded dimers.
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Yilmaz, Engin. "Cracked Elastic Annulus Bonded To Rigid Cylinder." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/2/12606782/index.pdf.
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In this study, a long annulus bonded to a rigid cylinder containing an axisymmetric circumferential crack of width (d-c) at the midplane is considered. The material of the annulus is assumed to be linearly elastic and isotropic. The external surface of the annulus is free of stress. Surfaces of the crack are subject to distributed compressive loads.
The Fourier and Hankel transform techniques are used to solve the governing equations which are reduced to a singular integral equation for crack surface displacement derivative. This integral equation is converted to a system of linear algebraic equations which are solved numerically by using Gauss-Lobatto and Gauss-Jacobi quadrature formulas. Then, the stress intensity factors at the edges of the crack are calculated. Results are presented in graphical form.
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Mas, Ivars Diego. "Bonded Particle Model for Jointed Rock Mass." Doctoral thesis, KTH, Teknisk geologi och geofysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12055.
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Jointed rock masses are formed of intact rock and joints. There-fore, proper characterization of rock mass behavior has to consid-er the combined behavior of the intact rock blocks and that of the joints. This thesis presents the theoretical background of the Synthetic Rock Mass (SRM) modeling technique along with example applica-tions. The SRM technique is a new approach for simulating the mechanical behavior of jointed rock masses. The technique uses the Bonded Particle Model (BPM) for rock to represent intact ma-terial and the Smooth-Joint Contact Model (SJM) to represent the in situ joint network. In this manner, the macroscopic behaviour of an SRM sample depends on both the creation of new fractures through intact material, and slip/opening of pre-existing joints. SRM samples containing thousands of non-persistent joints can be submitted to standard laboratory tests (UCS, triaxial loading, and direct tension tests) or tested under a non-trivial stress path repre-sentative of the stresses induced during the engineering activity under study. Output from the SRM methodology includes pre-peak properties (modulus, damage threshold, peak strength) and post-peak proper-ties (brittleness, dilation angle, residual strength, fragmentation). Of particular interest is the ability to obtain predictions of rock mass scale effects, anisotropy and brittleness; properties that can-not be obtained using empirical methods of property estimation. Additionally, the nature of yielding and fracturing can be studied as the rock mass fails. This information can improve our understand-ing of rock mass failure mechanisms.QC20100720
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Higgins, Edward Donald. "The strength of bonded wood strand composites." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30613.
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A method for modelling the strength of bonded wood strands which are oriented principally in one direction is proposed. The hypothesis tested was that strand grain orientation data, fitted to a von Mises probability distribution, could be used in an analysis for estimating the potential tensile strength of an ideally bonded composite. The strand strength, resolved at any loading angle with respect to the principal composite strand orientation axis, was multiplied by the distribution probability at that angle. When integrated over all angles, this product yielded the mathematical expectation of strength for the composite. The model predicted composite strength at off-orientation axis angles and represented the material in two dimensions in an orthotropic fashion. A feature of this research is the use of a parametrically quantified strand orientation level in an algorithm developed to estimate composite strength.
A practical number of strand angle readings (100) were taken to characterize each composite. These angle readings defined orientation in terms of a parameter which described composites ranging from random to highly oriented. The model input also required microtensile strength means from samples of strands tested in the longitudinal and radial or tangential directions.
Comparisons between the model and actual specific strengths were made at five equally spaced-composite principal axis load angles from 0 to 90 degrees. Both tensile and flexural tests were performed to evaluate the model. The evaluations were designated in terms of resin content, distribution, and droplet
size. These variables were studied using colorimetry and computerized image analysis. Composite density profiles through the specimens' thickness were obtained from direct reading x-ray densitometry. Composites made of juvenile trembling aspen, red alder, red cedar, mature lodgepole pine and yellow birch were studied.
Assumptions concerning wood shear strength and strand length/thickness ratio were discussed in the interpretation of an overlapping strand stress-transfer model. This led to the definition of failure criteria based on stress transfer. A trial of orientation modelling in elasticity estimation was made and a random function model of composite elasticity based on laminated plate theory is outlined in a supplementary proposal for further research.
The simplified algorithm for the strength of aligned.wood strand composites provides design targets for reconstituted high strength strand lumber and panel products of the future.Forestry, Faculty of
Graduate
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White, Caleb, and caleb white@rmit edu au. "Health Monitoring of Bonded Composite Aerospace Structures." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090602.142122.
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Airframe assemblers have long recognised that for a new aircraft to be successful it must use less fuel, have lower maintenance requirements, and be more affordable. One common tactic is the use of innovative materials, such as advanced composites. Composite materials are suited to structural connection by adhesive bonding, which minimises the need for inefficient mechanical fastening. The aim of this PhD project was to investigate the application of existing, yet immature Structural Health Monitoring (SHM) techniques to adhesively bonded composite aerospace structures. The PhD study focused on two emerging SHM technologies - frequency response and comparative vacuum monitoring (CVM). This project aimed to provide missing critical information for each technique. This included determining sensitivity to damage, repeatability of results, and operating limitations for the frequency response method. Study of the CVM technique aimed to address effectiveness of damage detection, manufacture of sensor cavities, and the influence of sensor integration on mechanical performance of bonded structures. Experimental research work is presented examining the potential of frequency response techniques for the detection of debonding in composite-to-composite external patch repairs. Natural frequencies were found to decrease over a discrete frequency range as the debond size increased; confirming that such features could be used to both detect and characterise damage. The effectiveness of the frequency response technique was then confirmed for composite patch and scarf repair specimens for free-free and fixed-fixed boundary conditions. Finally, the viability of the frequency response technique was assessed for a scarf repair of a real aircraft component, where it was found that structural damping limited the maximum useable frequency. The feasibility of CVM technique for the inspection of co-cured stiffener-skin aircraft structures was explored. The creation of sensor cavities with tapered mandrels was found to significantly alter the microstructure of the stiffener, including crimping and waviness of fibres and resin-rich zones between plies. Representative stiffened-skin structure with two sensor cavity configurations (parallel and perpendicular to the stiffener direction) was tested to failure in tension and compression. While tensile failure strength was significantly reduced for both configurations (up to 25%), no appreciable differences in compression properties were found. Two potential sensor cavity configurations were investigated for the extension of the CVM technique to pre-cured and co-bonded scarf repair schemes. The creation of radial and circumferential CVM sensor cavities was found to significantly alter the microstructure of the adhesive bond-line and the architecture of the repair material in the case of the co-bonded repair. These alterations changed the failure mode and reduced the tensile failure strength of the repair. A fibre straightening mechanism responsible for progressive failure (specific to co-bonded repairs with circumferential cavities) was identified, and subsequently supported with acoustic emission testing and numerical analysis. While fatigue performance was generally reduced by the presence of CVM cavities, the circumferential cavities appeared to retard crack progression, reducing sensitivity to the accumulation of fatigue damage. These outcomes have brought forward the implementation of SHM in bonded composite structures, which has great potential to improve the operating efficiency of next generation aircraft.
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Golubovic, Adnan. "Analysis and optimization of adhesively bonded joints." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0033/MQ64221.pdf.
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Raman, Jaya. "Microleakage of dentine-bonded root canal fillings." Thesis, Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39558253.
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Wang, Xueqin. "Morphology distributions in thermally point bonded nonwovens." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/8696.
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Valentin, Rodolfo V. "Finite element analysis of adhesively bonded joints." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17575.
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Ford, Theodore Robert. "Thermal conductivity of bonded hollow-sphere monoliths." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/20045.
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關健明 and Kin-ming Kwan. "An expert system for adhesive-bonded joints." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31212347.
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Khoramishad, Hadi. "Modelling Fatigue Damage in Adhesively Bonded Joints." Thesis, University of Surrey, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520467.
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The aim of this research was to develop a reliable predictive fatigue damage model for adhesively bonded structures. It was necessary for such a numerical model to be independent of geometry of the structure and capable of considering different fatigue damage phases, of simulating the experimentally measured damage evolution and of predicting the effect of main fatigue loading characteristics. Three different adhesively bonded joints, namely the single lap joint, the laminated doubler in bending and the mixed-mode flexure specimen manufactured with the same adhesive system were considered for experimental and numerical investigations. The bonded joints were tested under quasi-static and fatigue loading and the failure responses of the bonded joints were studied experimentally and modelled numerically. To assess static and fatigue progressive damage in the bonded joints, experimental approaches, including backface strain and video microscopy techniques were employed. The effect of important fatigue loading parameters including the maximum fatigue load level and the load ratio on the failure behaviour of the bonded joints was examined experimentally. A cohesive zone model with a bi-linear traction-separation response was used to simulate the progressive damage in the adhesively bonded joints. This cohesive zone model was integrated with a damage mechanics based fatigue model to simulate the deleterious influence of fatigue loading. The proposed fatigue damage model was able to account for the effects of fatigue loading characteristics including the maximum fatigue load and fatigue load ratio. The static and fatigue damage models were calibrated, validated and optimised against the experimental results obtained and other published experimental data. The fatigue damage model was applied to adhesively bonded joints subjected to constant and variable amplitude fatigue loading. The model was able to successfully predict the detrimental effect of the variable amplitude fatigue loading as well as the constant amplitude fatigue loading. The proposed fatigue damage model was generally found to be a significant improvement on other damage models available for adhesively bonded structures
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Keat, Loh Wei. "Modelling interfacial degradation in adhesively bonded structures." Thesis, University of Surrey, 2002. http://epubs.surrey.ac.uk/798102/.
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Hua, Yongxia. "Modelling environmental degradation in adhesively bonded joints." Thesis, University of Surrey, 2006. http://epubs.surrey.ac.uk/804411/.
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Jones, D. W. "Vapour sorption by latex bonded carbon particles." Thesis, Nottingham Trent University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372741.
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