There is a need to monitor the existence and effects of damage in structural materials. Aircraft components provide a much publicized example, but the need exists in a variety of other structures, such as layered materials used in food packaging industries. While several techniques and models have been proposed for material characterization and condition monitoring of bulk materials, less attention has been devoted to thin sheets having no flexural rigidity. This study is therefore devoted to the development of a new method for acoustic Non-Destructive Testing (NDT) and material characterization of thin sheets used in food packaging materials or similar structures. A method for assessing the strength in the presence of crack of thin sheets used in food packaging is first presented using a modified Strip Yield Model (SYM). Resonance frequency measurement is then introduced and it is shown, at low frequency range (less than 2kHz), that a change in the physical properties such as a reduction in stiffness resulting from the onset of cracks or loosening of a connection causes detectable changes in the modal properties, specifically the resonance frequency. This observation leads to the implementation of a simple method for damage severity assessment on sheet materials, supported by a new theory illustrating the feasibility of the detection of inhomogeneity in form of added mass, as well as damage severity assessment, using a measurement of the frequency shift. A relationship is then established between the resonance frequency and the material’s elastic property, which yields a new modality for sheet materials remote characterization. The result of this study is the groundwork of a low-frequency vibration-based method with remote acoustic excitation and laser detection, for nondestructive testing and material characterization of sheet materials. The work also enhances the feasibility of the testing and condition monitoring of real structures in their operating environment, rather than laboratory tests of representative structures. The sensitivity of the new experimental approach used is liable to improvement while being high because the frequency measurement is one of the most accurate measurements in physics and metrology.

The electric Joule heating of solid materials through direct current excitation can be used to generate a temperature profile throughout a powdermetallic (P/M) compact. When recording the surface temperature distribution with an infrared (IR) camera important information regarding the integrity of the sample can be gained. This research will concentrate on the formulation of a mathematical model capable of predicting the temperature distribution and heat flow behavior in P/M parts and its relations to the supplied current, injection method, geometric shape as well as the thermo-physical properties. This theoretical model will subsequently be employed as a tool to aid in the actual measurements of infrared signatures over the sample surface and their correlation with the detection of surface and subsurface flaws. In this work we will develop the theoretical background of IR testing of green-state and sintered P/M compacts in terms of stating the governing equations and boundary conditions, followed by devising analytical and numerical solutions. Our main emphasis is placed on modeling various flaw sizes and orientations in an effort to determine flaw resolution limits as a function of minimally detectable temperature distributions. Preliminary measurements with controlled and industrial samples have shown that this IR testing methodology can successfully be employed to test both green-state and sintered P/M compacts.

Remoções quase totais de clorofenóis, por processos anaeróbios, já foram atingidas mediante elevada concentração de matéria orgânica e um número considerável de fontes de carbono. Porém, é necessário que se investigue o desempenho dos reatores submetidos a condições menos idealizadas. Este trabalho apresenta o desenvolvimento de uma metodologia para avaliar um reator anaeróbio de leito fluidificado (RALF) como etapa de pré-tratamento de substrato sintético contendo pentaclorofenol (PCP). Para isso, foram adotadas as seguintes condições experimentais: fonte única de carbono; concentração reduzida de matéria orgânica; biomassa não previamente adaptada, e menores tempos de detenção hidráulica. Para cumprir o objetivo citado, foram desenvolvidos dois reatores, com 2,2 e 16 litros, respectivamente, e foram realizadas etapas de avaliação de materiais suporte, estudo de diversas interações (partícula/fluido, partículas fluido, biopartícula/fluido e biopartículas/fluido), e análise do desempenho do RALF sem PCP e com PCP. Os materiais suporte escolhidos foram a alumina, o basalto e o carvão ativado granular, todos com diâmetros próximos a 3 mm. Eles foram avaliados em ensaios de caracterização física, de microscopia eletrônica de varredura, de fluidodinâmica e de análise de imagens. O carvão apresentou os melhores resultados e foi escolhido para a continuidade do trabalho. As interações foram analisadas através de ensaios fluidodinâmicos, isotermas de adsorção, dentre outros. Nas condições experimentais utilizadas, a biomassa aumentou a densidade da partícula, fato que foi comprovado pelos ensaios para determinação da velocidade mínima de fluidificação, de expansão e porosidade do leito, e também de velocidade terminal da partícula isolada. As isotermas de adsorção demonstraram que a presença de matéria orgânica diminuiu em 9% a adsorção do PCP. O RALF apresentou um comportamento satisfatório no período de operação sem PCP. Nos 105 dias de operação, a eficiência média de remoção de DQO ficou quase sempre superior a 90%, e os outros parâmetros de monitoramento de desempenho apresentaram valores típicos, indicando estabilidade no processo. A presença de PCP no sistema, nas concentrações utilizadas, não alterou a qualidade da biomassa presente, e nem os parâmetros de monitoramento de desempenho, como DQO, alcalinidade, pH e ácidos voláteis. Mesmo sob condições menos idealizadas, foi observado um desempenho satisfatório do reator na remoção do PCP. Em concentrações variando de 1 a 6 mg/L, foram observadas eficiências médias de remoção de 93% e 70%, respectivamente, para os 80 dias de operação nessas condições. Diante dos resultados obtidos, foi possível concluir que a remoção de PCP em um RALF pode ser atingida mediante condições operacionais mais simples. / The almost total removal of chlorophenols by anaerobic processes has been achieved under high concentrations of organic matter and a considerably large number of carbon sources. However, it is necessary to investigate the performance of such reactors under less idealized conditions. The present work shows the development of a new methodology for evaluating the use of an anaerobic fluidized bed reactor (AFBR) in the pretreatment step of a synthetic substrate containing pentachlorophenol (PCP). In order to do that, the following experimental conditions were used: a single source of carbon; reduced concentrations of organic matter; non-previously adapted biomass, and smaller hydraulic retention times. To achieve the main objective, two reactors, one having a volume of 2.2 L and the other one, 16 L, were especially designed; evaluation steps of support material and the study of several interactions (particle/fluid, particles/fluid, bioparticle/fluid, bioparticles/fluid) were carried out, and the performance of the AFBR with and without PCP was analyzed. The three support materials employed were alumina, basalt and granular activated carbon, all having average diameters of 3 mm. These materials were evaluated through physical characterization methods, microscopy, hydrodynamic and image analyses. The activated coal showed the best results and was exclusively employed in the remainder of the work. The interactions were analyzed by hydrodynamics and adsorption isotherms, to name but a few. Under the experimental conditions employed, the biomass made the particle density increase, a fact that was verified in the determination of the minimum fluidization velocity, the bed porosity and expansion as well as the terminal velocity of isolated particles. The adsorption isotherms showed a decrease of 9% in PCP absorption due to the existence of organic matter. The AFBR showed satisfactory results during the operation without PCP. In the 105 days of operation, the average efficiency of COD removal remained almost always over 90%, while the other performance monitoring parameters remained at typical values, indicating the process stability. The presence of PCP under the concentrations used in the system did not seem to affect neither the quality of the biomass nor the performance monitoring parameters, like COD, alkalinity, pH and volatile acids. Even under less idealized conditions, the reactor showed good performance in removing PCP. The average efficiencies of removal attained around 93% and 70% for concentrations of 1 to 6 mg/L respectively. These concentration levels were kept during 80 days. In view of the results obtained, it is possible to conclude that reasonably good efficiency of PCP removal in AFBR can be attained under simpler operational conditions.

Made available in DSpace on 2016-04-28T18:22:38Z (GMT). No. of bitstreams: 1 Gabriela Dias Yamasaki.pdf: 2385461 bytes, checksum: b14a9e1fc83177fc854cef696a21dfd8 (MD5) Previous issue date: 2013-01-30 / The interest in researches related to English teaching and learning for children has motivated a growing number of studies in recent decades. However, there are still very few studies that explore the evaluation of teaching materials for such group, a fact that motivated the development of this work. In this way, this study aims at evaluating a didactic unit used for English teaching and learning in an institution that provides social services for lower class children in the south of São Paulo. This unit, called Identity was developed by PEIC, a project originated from an offshoot of the project "Training teachers for English teaching and learning for children" which aims to develop teachers on teaching and learning through critical and reflexive practice. The theoretical framework of this work consists of the following studies: the socio-historical-cultural teaching and learning (VYGOTSKY, 1934/1993; 1934/1998), the characteristics of the child as a learner of languages (MOON, 2000; HALLIWELL, 1992; READ, 2007; PINTER, 2006), issues related to identity (HALL, 1992/2001; NORTON, 1997), the requirements of the Brazilian official documents described in PCN-LE (BRAZIL, 1998) and considerations on the production and evaluation of instructional materials (CUNNINGSWORTH, 1995; TOMLINSON, 2001.2003; GRAVES, 2000; RAMOS, 2009). The results showed that the material assessed proposes learning of the English language through peer interaction, with a socio-historical-cultural view of language and learning and spiral design. Moreover, it has proved to be efficient, because it proposes language development through actions which advocate respect and dignity to children, thus fulfilling a role as an agent of social integration / O interesse por estudos sobre o ensino-aprendizagem de inglês para crianças tem motivado um número crescente de pesquisas nas últimas décadas. Contudo, ainda são escassos os estudos sobre a avaliação de materiais didáticos para essa faixa etária, fato que motivou o desenvolvimento deste trabalho. Assim, este estudo se desenvolve com o objetivo de avaliar uma unidade didática utilizada para o ensino-aprendizagem de inglês em uma instituição que atende crianças pertencentes às classes D e E na zona sul de São Paulo. Essa unidade, denominada Identidade (Identity) foi elaborada pelo projeto PEIC, um desdobramento do projeto "Formação de professores para o ensino-aprendizagem de inglês para crianças" que visa a formação crítico-reflexiva de professores de inglês. O referencial teórico que embasou este trabalho constituiu-se pelos seguintes estudos: a perspectiva sócio-histórico-cultural de ensino-aprendizagem (VYGOTSKY, 1934/1993; 1934/1998), as características da criança como aprendiz de línguas (MOON, 2000; HALLIWELL, 1992; READ, 2007; PINTER, 2006), as questões relacionadas à identidade (HALL, 1992/2001; NORTON, 1997), as prescrições dos documentos oficiais brasileiros prescritas nos PCN-LE (BRASIL, 1998) e as considerações sobre a produção e a avaliação de materiais didáticos (CUNNINGSWORTH, 1995; TOMLINSON, 2001,2003; GRAVES, 2000; RAMOS, 2009). Os resultados mostraram que o material avaliado propõe o aprendizado de língua inglesa por meio da interação entre pares, tem uma visão sócio-histórico-cultural de linguagem e aprendizagem e design em espiral. Além disso, mostrou-se eficiente, pois propõe desenvolver por meio da linguagem ações que preconizam o respeito e a dignidade às crianças, cumprindo assim um papel como agente de inserção social

Remoções quase totais de clorofenóis, por processos anaeróbios, já foram atingidas mediante elevada concentração de matéria orgânica e um número considerável de fontes de carbono. Porém, é necessário que se investigue o desempenho dos reatores submetidos a condições menos idealizadas. Este trabalho apresenta o desenvolvimento de uma metodologia para avaliar um reator anaeróbio de leito fluidificado (RALF) como etapa de pré-tratamento de substrato sintético contendo pentaclorofenol (PCP). Para isso, foram adotadas as seguintes condições experimentais: fonte única de carbono; concentração reduzida de matéria orgânica; biomassa não previamente adaptada, e menores tempos de detenção hidráulica. Para cumprir o objetivo citado, foram desenvolvidos dois reatores, com 2,2 e 16 litros, respectivamente, e foram realizadas etapas de avaliação de materiais suporte, estudo de diversas interações (partícula/fluido, partículas fluido, biopartícula/fluido e biopartículas/fluido), e análise do desempenho do RALF sem PCP e com PCP. Os materiais suporte escolhidos foram a alumina, o basalto e o carvão ativado granular, todos com diâmetros próximos a 3 mm. Eles foram avaliados em ensaios de caracterização física, de microscopia eletrônica de varredura, de fluidodinâmica e de análise de imagens. O carvão apresentou os melhores resultados e foi escolhido para a continuidade do trabalho. As interações foram analisadas através de ensaios fluidodinâmicos, isotermas de adsorção, dentre outros. Nas condições experimentais utilizadas, a biomassa aumentou a densidade da partícula, fato que foi comprovado pelos ensaios para determinação da velocidade mínima de fluidificação, de expansão e porosidade do leito, e também de velocidade terminal da partícula isolada. As isotermas de adsorção demonstraram que a presença de matéria orgânica diminuiu em 9% a adsorção do PCP. O RALF apresentou um comportamento satisfatório no período de operação sem PCP. Nos 105 dias de operação, a eficiência média de remoção de DQO ficou quase sempre superior a 90%, e os outros parâmetros de monitoramento de desempenho apresentaram valores típicos, indicando estabilidade no processo. A presença de PCP no sistema, nas concentrações utilizadas, não alterou a qualidade da biomassa presente, e nem os parâmetros de monitoramento de desempenho, como DQO, alcalinidade, pH e ácidos voláteis. Mesmo sob condições menos idealizadas, foi observado um desempenho satisfatório do reator na remoção do PCP. Em concentrações variando de 1 a 6 mg/L, foram observadas eficiências médias de remoção de 93% e 70%, respectivamente, para os 80 dias de operação nessas condições. Diante dos resultados obtidos, foi possível concluir que a remoção de PCP em um RALF pode ser atingida mediante condições operacionais mais simples. / The almost total removal of chlorophenols by anaerobic processes has been achieved under high concentrations of organic matter and a considerably large number of carbon sources. However, it is necessary to investigate the performance of such reactors under less idealized conditions. The present work shows the development of a new methodology for evaluating the use of an anaerobic fluidized bed reactor (AFBR) in the pretreatment step of a synthetic substrate containing pentachlorophenol (PCP). In order to do that, the following experimental conditions were used: a single source of carbon; reduced concentrations of organic matter; non-previously adapted biomass, and smaller hydraulic retention times. To achieve the main objective, two reactors, one having a volume of 2.2 L and the other one, 16 L, were especially designed; evaluation steps of support material and the study of several interactions (particle/fluid, particles/fluid, bioparticle/fluid, bioparticles/fluid) were carried out, and the performance of the AFBR with and without PCP was analyzed. The three support materials employed were alumina, basalt and granular activated carbon, all having average diameters of 3 mm. These materials were evaluated through physical characterization methods, microscopy, hydrodynamic and image analyses. The activated coal showed the best results and was exclusively employed in the remainder of the work. The interactions were analyzed by hydrodynamics and adsorption isotherms, to name but a few. Under the experimental conditions employed, the biomass made the particle density increase, a fact that was verified in the determination of the minimum fluidization velocity, the bed porosity and expansion as well as the terminal velocity of isolated particles. The adsorption isotherms showed a decrease of 9% in PCP absorption due to the existence of organic matter. The AFBR showed satisfactory results during the operation without PCP. In the 105 days of operation, the average efficiency of COD removal remained almost always over 90%, while the other performance monitoring parameters remained at typical values, indicating the process stability. The presence of PCP under the concentrations used in the system did not seem to affect neither the quality of the biomass nor the performance monitoring parameters, like COD, alkalinity, pH and volatile acids. Even under less idealized conditions, the reactor showed good performance in removing PCP. The average efficiencies of removal attained around 93% and 70% for concentrations of 1 to 6 mg/L respectively. These concentration levels were kept during 80 days. In view of the results obtained, it is possible to conclude that reasonably good efficiency of PCP removal in AFBR can be attained under simpler operational conditions.