Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1933. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed July 15, 2010)

Thesis (M.Sc.)--City University of Hong Kong, 2005. / At head of title: City University of Hong Kong, Department of Physics and Materials Science, Master of Science in materials engineering & nanotechnology dissertation. Title from title screen (viewed on Sept. 4, 2006) Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Donald R. Paul. Vita. Includes bibliographical references.

Thesis (Ph.D.)(Metallurgical Engineering)--University of Pretoria, 2006. / Includes summary. Includes bibliographical references. Available on the Internet via the World Wide Web.

Orientador: Maria Margarita Torres Moreno / Banca: Lucy Gomes Sant'Anna / Banca: José Francisco Marciano Motta / Banca: Antonio Carlos Artur / Banca: Antenor Zanardo / Resumo: Apesar do processo por via seca não permitir grandes quantidades de aditivos na composição das massas cerâmicas em relação ao processo por via úmida, nada impede que sejam utilizados outros materiais, a fim de melhorar propriedades químicas, reduzir ciclos de queima e economizar energia e combustível, além de racionalizar o uso de jazidas de argila, impedindo que os rejeitos dessas minas contribuam como poluentes para o meio ambiente. O objetivo principal deste trabalho consiste em adicionar filitos do Grupo São Roque, granitos dos Complexos Graníticos Itu e São Roque, rochas intrusivas básicas da região de Limeira, gnaisses e quartzitos do Complexo Itapira e siltitos argilosos da Formação Tatuí às argilas da mina Sartori (Formação Corumbataí) procurando-se melhorar as propriedades cerâmicas dessa massa e demonstrar que a adição de aditivos naturais pode contribuir na solução de muitos problemas apresentados pelas industrias cerâmicas .da região. A metodologia baseou-se na caracterização química (determinação da quantidade de elementos maiores e menores, Capacidade de Troca Catiônica e carbono orgânico), mineralógica (descrição microscópica, Difração de Raios X e análise térmica) e física (ensaios tecnológicos cerâmicos) das referidas argilas, assim como dos aditivos citados, buscando relacionar essas características mineralógicas e químicas com o bom ou péssimo desempenho das massas cerâmicas nos ensaios físicos. Todas as massas aditivadas , apresentaram bons resultados segundo as Normas 13817 e 13818 da ABNT, podendo ser utilizados como pisos e revestimentos cerâmicos. Destacam-se com os melhores resultados de propriedades cerâmicas os corpos de prova aditivados com diabásio, gnaisse, quartzito e o siltito argiloso da Formação Tatuí. A amostra pura de siltito argiloso da Formação Tatuí foi testada como material para revestimento...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In spite of the dry way process does not require great amounts of addictive in the composition of the ceramic masses, in relation to the wet way process, nothing prevents that other materials can be used, in order to improve chemical properties, reduce firing cycles and save energy and fuel, besides rationalizing the usage of the clay mines, preventing that the wastes of these mines contribute as poluents to the environment. The main objective of this work consists of adding phyllites from São Roque Group, granites from the Itu and São Roque Granitic Complex, basic intrusive rocks from the region of Limeira, gnaisses and quartzites from the Itapira Complex and siltstones from the Tatuí Formation to the clays from the Sartori mine (Corumbataí Formation), in order to improve the ceramical properties of this ceramic mass and display that the add of natural materials may contribute in the solution of many problems faced by the ceramic industries of the region. The approach based on the chemical characterization (determination of the amount of larger and smaller elements, Cathionic Exchange Capacity and organic carbon), mineralogical (microscopic description, X-Ray Diffraction and thermal analysis) and physical (ceramic technological assays) of the referred clays, as well as of the addictives mentioned above, trying to relate the chemical and mineralogical characters with the good or bad performance of the ceramic masses at the physical assays. All the materials added in the masses from Corumbataí Formation presented good results according to ABNT Norms, and they can be used as floor and wall tiles as well. The best ceramic mass were those added with diabase, gnaisse, quartzit and clay siltstone from Tatuí Formation. The sample of Tt pure was analyzed as raw material for the floor tiles, and it didn't present good results. This sample has a great potential for heavy clay proudcts (bricks and roof tiles). / Doutor

Soil stabilization is a common technique to increase the strength and durability and also to reduce the swell-shrink behavior of foundation soil or subgrade soil in pavement. Nowadays, several nontraditional stabilizers (e.g., Polymer, Enzyme, Ionic stabilizer etc.) are available in market whose behavior is not fully understood for wide range of soil types. In the present study two types of soils i.e., Carbondale soil ‘clay with high plasticity (CH)’ and Galatia soil ‘silt with low plasticity (ML)’ has been used. A commercially available liquid polymer “Soiltac” was selected as a stabilizer and mixed with both the soils at various percentages i.e., 0.0%, 0.5%, 1.0%, 1.5% and 3.0% by dry weight of soil to study the effect of polymer on geotechnical properties of soil. Particle size distribution, liquid limit, plastic limit, specific gravity and standard Proctor tests were conducted to identify the basic index properties of the soil. Unconfined Compressive Strength (UCS) tests were conducted after 3 days, 7 days and 28 days of curing period for CH soil. For ML soil, UCS tests were carried out after 7 days and 28 days of curing period. In addition, California Bearing Ratio (CBR) tests were conducted for CH soil at unsoaked and soaked (soaked for 96 hours) conditions. With the addition of stabilizer, no significant changes in UCS values were obtained for ML soil. For CH soil, UCS values increases upto 1.5% stabilizer dose and then decreases with 3.0% of stabilizer. Also, for CH soil, UCS value increases with the increase in curing period. For CH soil, the unsoaked CBR value increases upto 1.5% stabilizer dose and then decreases with 3.0% of stabilizer but no significant improvement in soaked CBR values were found.

The liquefaction resistance of undisturbed soil samples collected from a selected location in Carbondale, Southern Illinois was evaluated by conducting cyclic triaxial tests. Index property tests were carried out on the sample for identification and classification of the soil. Cyclic triaxial tests were conducted on undisturbed sample after saturation, undisturbed sample at natural water content and remolded samples prepared by compaction in the lab. The results were used to evaluate the effect of saturation and remolding on liquefaction resistance of the local soil. Effect of effective confining pressure on dynamic properties of soil (Young's Modulus and Damping ratio) was also studied. Forty five stress controlled cyclic triaxial tests were performed. Three different values of initial effective confining pressure (5 psi, 10 psi and 15 psi) were used and cyclic stress ratio was varied from 0.1 to 0.5 in order to apply different cyclic shear stresses. The results show that the cyclic load resistance of soil decreases as a result of remolding. Saturated undisturbed samples show increase in resistance to liquefaction with increase in initial confining pressure. Remolded samples were prepared by compaction in the lab keeping unit weight and water content equal to that of undisturbed samples. Remolded samples show increase in liquefaction resistance with increase in confining pressure. Undisturbed samples at natural water content show increase in resistance to develop axial strain with increase in confining pressure. Both the rate of excess pressure development and axial strain development increase significantly as a result of remolding. While investigating the effect of saturation of undisturbed samples on liquefaction resistance of soil, interesting observations were made. The excess pressure buildup rate was faster in case of saturated undisturbed samples compared to that in samples with natural water content. On the other hand, rate of strain development was significantly high in case of sample with natural water content compared to that in saturated sample. Also, results obtained from cyclic triaxial tests on saturated undisturbed samples were compared with results obtained from similar tests on Ottawa Sand (Lama 2014) sample. The comparison shows that the saturated undisturbed soil samples of the selected local soil have very high resistance to liquefaction both in terms of initial liquefaction and development of 2.5% and 5% axial strain. Modulus of Elasticity and damping ratio were studied as important dynamic properties of soil. Young's Modulus was observed to decrease significantly at higher strain levels for all three types of samples. Young's modulus increased with increase in effective confining pressure, the effect of confining pressure being large at low strain level and almost insignificant at higher strain level. Damping ratio was highest in undisturbed sample at natural water content and smallest in remolded sample and damping ratio for saturated undisturbed sample falls in between. The damping ratio did not show any definite correlation with strain and confining pressure at lower strain level. But, for strain higher than 1% double amplitude axial strain, damping ratio significantly decreases with increase in strain. Damping ratio increases with increase in confining pressure as observed at high strain for all samples.

Made available in DSpace on 2014-06-11T19:32:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-26Bitstream added on 2014-06-13T21:03:32Z : No. of bitstreams: 1 carvalho_hwp_dr_araiq.pdf: 11718148 bytes, checksum: 17599ea6cfdccc04a405f3dc52129f1d (MD5) / Une des manières d'augmenter la stabilité thermique de polymères consiste à leur ajouter de faibles quantités d'argile dispersées dans échelle nanométrique. De tels matériaux sont appelés de « nanocomposites ». Il existe plusieurs explications à ce phénomène, comme les effets de barrière de diffusion et la formation de charbon. D’autres sont en cours de vérification, comme les effets de piégeage de radicaux par les ions qui participent à des réactions de type Fenton. Notre objectif a été de suivre in situ des transformations chimiques de la phase argile, afin de mieux comprendre comment ces nanostructures lamellaires retardent la décomposition de polymères. Pour ce faire, trois types de nanocomposites ont été préparés: i) Poly(méthyl méthacrylate)-co-Poly(trimetoxysilil propyl méthacrylate) et argiles montmorillonite (MMT) du type Cloisite (PMMA-co-PTMSM-Cloisite); ii) PMMA-argiles montmorillonites naturelles contenant différents taux d’ions Fe3+ dans les couches octaédrique (PMMA-MMT); iii) PMMA-hydroxydes doubles lamellaires (HDL), avec différentes proportions d’ ions Zn2+, Cu2+ et Fe3+ PMMA-HDL. La thermo-décomposition des argiles primitives et de leurs nanocomposites ont été suivies par des analyses thermiques, de diffusion de rayons X (SAXS et WAXS) et par spectroscopie d'absorption de rayons X (EXAFS). Les effets de l'atmosphère, de la composition chimique des lamelles, et de la quantité d'argile employée dans l'obtention des nanocomposites ont été évalués. L'étude des nanocomposites, PMMA-co-PTMSM-Cloisite a mis en évidence deux mécanismes de stabilisation. Elle a montré que l'addition d’argiles résulte en une stabilisation plus importante sous atmosphère d'air, que sous atmosphère de N2, et est aussi plus importante selon la quantité d'argile dispersée dans le polymère. La formation... (Résumé complet accès életronique cidessous) / Uma das maneiras de aumentar a estabilidade térmica de polímeros consiste na adição de baixas quantidades de argila dispersas em escala nanométrica. Tais materiais são chamados de nanocompósitos. Existem várias explicações de como as argilas promovem a estabilização térmica dos polímeros. Algumas delas bem estabelecidas, como os efeitos de barreira de difusão e formação de carvão. E outras em curso de verificação, como os efeitos de seqüestro de radicais por parte de íons que participam de reações tipo Fenton. Nesse trabalho buscou-se, através do monitoramento in situ das transformações químicas da fase argila, melhor compreender como essas nanoestruturas lamelares retardam a decomposição de polímeros. Para tanto preparam-se três tipos de nanocompósitos: i) Poli(metil metacrilato)-co- Poli(trimetoxisilil propil metacrilato) e argilas montmorilonita (MMT) do tipo Cloisite (PMMA-co-PTMSM-Cloisite); ii) PMMA-argilas montmorilonita naturais contendo diferentes razões de íons Fe3+ nas camadas octaédricas (PMMA-MMT); iii) PMMAhidróxidos duplos lamelares (HDL), com diferentes proporções de íons Zn2+, Cu2+ e Fe3+ PMMA-HDL. A termo-decomposição das argilas primitivas e dos respectivos nanocompósitos foram acompanhadas por análises térmicas, espalhamento de raios X a baixos e altos ângulos (SAXS e WAXS) e espectroscopia de absorção de raios X (EXAFS). Os efeitos da atmosfera, composição química das lamelas, e quantidade de argila empregada na obtenção dos nanocompósitos foram avaliadas. O estudo dos nanocompósitos, PMMA-co-PTMSM-Cloisite mostrou que a estabilização térmica aumenta como função da quantidade de argila dispersa no polímero. O efeito de estabilização é mais pronunciado sob atmosfera de ar, do que em atmosfera de N2. A formação de carvão também foi observada apenas sob...

Made available in DSpace on 2014-06-11T19:32:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-11-28Bitstream added on 2014-06-13T21:04:08Z : No. of bitstreams: 1 thomazella_hr_dr_rcla.pdf: 7347686 bytes, checksum: 24913e7a63a4d7492c6c078e1b4fc55e (MD5) / Este estudo trata de aspectos ligados a duas grandes áreas do conhecimento científico, a geologia e a ciência dos materiais, em especial a área cerâmica. A arte de se fazer cerâmica representa a tangência entre estas duas ciências. O ponto do trabalho principal é a descrição e a avaliação de um depósito de argila plástica branca, também conhecida como ball clay, na região de Tambaú (SP), às margens do Rio Pardo. Este tipo de argila tem especial utilidade da industria cerâmica de revestimentos, atuando como componente suspencionante, plastificante e clareador de massas fabricadas por processo via úmida. Também pode ser um nobre componente para fabricação de engobes. O depósito estudado é uma extensa várzea, cujo rico depósito contém argilas plásticas comparáveis as argilas hoje disponíveis e abastecendo o parque industrial de revestimentos do sudeste brasileiro. Os estudos mineralógicos revelaram aspectos interessantes sobre áreas fontes para estes sedimentos e aspectos ligados à deposição destas argilas. Os ensaios individuais e de formulação mostraram o desempenho das argilas estudadas, e quando comparadas às argilas disponíveis no mercado, mostraram a sua viabilidade técnica com qualidade destacada. / This study deals with aspects linked to two great areas of knowledge: Geology and The Science of Materials, particularly the ceramic. The art of making ceramic represents the tangency between these two sciences. The main point of this work is the description and the evaluation of the white plastic clay deposit; also know as ball clay, in the region of Tambaú (SP), on the riversides of the Pardo River. This kind of clay has a special utility in the ceramic industry of revestment, acting as a suspending, molding and bleaching component of powders made throughout a spray drayer process. It can also be a noble component of making engobe. The deposit studied is a locate on de vast, low and flat land alongside the river whose rich deposit contains plastic clay compared with the clay which is available and supplies the revestment industries in southeast Brazil. The mineralogical studies reveal interesting aspects about areas which are sources for these sediments and aspects concerning this clay deposition. The individual and formulation tests have shown the studied clay performance, and when is already in the market, the studies have shown its technical feasibility with distinguished quality.

Art has the power to bring together communities of people who have suffered from traumatic experiences, and allow them to heal, and overall dismantles the stigma associated with it. My work delves into the emotional side of living with pediatric cancer from the child’s perspective, particularly my own experiences as a brainstem tumor survivor, and the overall concerns of fragility. This paper explores these perspectives that are severely lacking throughout studies, while also taking a closer look at how artists, such as Frida Kahlo and Jamie Bates Slone, have used art to reflect on and express emotions concerning personal traumas. My thesis project demonstrates how art, or in my case clay, can emphasize the resiliency of young children in overcoming pediatric cancer, and fosters a greater understanding, by focusing on the hopeful side of the diagnosis, in those who may only recognize fragility.