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

Obtenção e caracterização de produtos panificados livres de glúten

Schamne, Cristiane 25 September 2007 (has links)
Made available in DSpace on 2017-07-21T18:53:02Z (GMT). No. of bitstreams: 1 Christiane Schamne.pdf: 2521926 bytes, checksum: b4f1eed111a019961433a0be8ece30f3 (MD5) Previous issue date: 2007-09-25 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / The celiac disease is associated to food ingestion containing gluten, a protein that is found in some vegetable raw materials, as wheat, rye, barley and oats, damaging the surface of the intestine mucosa, making difficult nutrients absorption by the organism. The celiac disease has been object of frequent technological and clinical research on food alternatives to persons having the disease. The objective of this study was to develop the gluten free baked products, having a good sensorial acceptance, using cassava starch with the addition of soybeans derived products . From the rice cream, the cassava starch and the maize starch used in the formulation, the experimental design for Simplex-Centróide mixtures was carried through, and after that the software called Statistica 7.0 was used, inserting the maximum limit restriction of 50% of cassava starch, resulting in the experimental design for mixtures, giving then seven samples. Using these seven samples, sensorial and instrumental analysis composed of specific volume, elasticity and firmness analysis was carried through. For the sensorial analysis, the optimized formulation of mixture was 50% of rice cream and 50% of cassava starch, and for the instrumental analysis, the optimal simultaneous point for the three conducted analyses was 20% of rice cream, 50% of maize starch and 30% of cassava starch. From these two optimal points, a second sensorial analysis was realized, and the optimal formulation obtained from instrumental analyses was significantly preferred (hedonic scale average=6,96±1,71, using scale of 1 to 9) comparing to the first sensorial analysis (hedonic scale average=5,77±1,83, using scale of 1 to 9). From these samples, it was realized the comparative analysis of specific volume, elasticity, firmness and triangular test between baked bread and pre-baked and freeze bread. The baked sample and the pre-baked and freeze sample showed differences only in product elasticity, having not showed sensorial difference between the samples analyzed. For the muffin, a sensorial analysis was conducted, that resulted on hedonic scale average 7,76±1,07, using scale of 1 to 9. It was realized instrumental analysis of specific volume, elasticity and firmness, and comparative analysis between baked muffin and pre-baked and freeze muffin, adopting the same procedure used for bread analysis. The baked muffin and pre-baked and freeze muffin differed on specific volume and elasticity, however they didn´t have any sensorial difference when the triangular test was applied. For both, the bread and muffin, it was realized the physic-chemistry, nutritional and microbiological analysis, and both were according to the current law. It was realized cost analyses of the developed products, and the conclusion was that they are economically according with similar products. / A doença celíaca está relacionada à ingestão de alimentos que contêm glúten, proteína presente em algumas matérias-primas vegetais, como trigo, centeio, cevada e aveia, danificando a superfície da mucosa do intestino, dificultando a absorção de nutrientes pelo organismo. A doença celíaca tem sido objeto freqüente de estudos clínicos e tecnológicos em busca de alternativas alimentares para indivíduos que sofrem da enfermidade. O objetivo desse trabalho foi desenvolver produtos panificados isentos de glúten, de boa aceitação sensorial, utilizando amido de mandioca e adicionados de derivados de soja. A partir do amido de mandioca, creme de arroz e amido de milho utilizados na formulação, foi realizado o delineamento experimental para misturas Simplex-Centróide, e posteriormente os dados foram lançados no software Statistica 7.0, inserindo-se a restrição do limite máximo de 50 % de amido de mandioca, que resultou no delineamento para misturas originando sete amostras. A partir dessas sete amostras, foram realizadas análises sensorial e instrumentais de volume específico, elasticidade e firmeza. Para a análise sensorial, a formulação ótima de mistura encontrada foi 50% de creme de arroz e 50% de amido de mandioca, e para a análise instrumental, o ponto ótimo simultâneo das três análises realizadas foi 20% de creme de arroz, 30% de amido de mandioca e 50% de amido de milho. A partir dos dois pontos ótimos obtidos, foi realizada uma segunda análise sensorial, na qual a formulação ótima obtida a partir das análises instrumentais realizadas foi significativamente preferida (média escala hedônica=6,96±1,71, numa escala de 1 a 9) em relação à formulação ótima obtida na primeira análise sensorial (média escala hedônica 5,77±1,83, numa escala de 1 a 9). A partir dessa amostra, foram realizadas análises comparativas de volume específico, elasticidade e firmeza, e teste triangular entre o pão assado e o pão pré-assado e congelado. A amostra assada e a amostra pré-assada e congelada do pão diferiram apenas com relação à elasticidade do produto, não sendo percebida nenhuma diferença sensorial entre as amostras analisadas.Para o muffin foi realizada análise sensorial, a qual apresentou média de escala hedônica de 7,76±1,07, numa escala de 1 a 9. Foram realizadas análises sensorial e instrumentais de volume específico, elasticidade e firmeza comparativas entre a amostra assada e a amostra pré-assada e congelada, adotando o mesmo procedimento aplicado ao pão. O muffin assado e o muffin pré-assado e congelado diferiram com relação ao volume específico e elasticidade, porém não apresentaram diferença sensorial significativa aplicando-se o teste triangular. Para ambos os produtos foram realizadas análises físico-químicas, nutricionais e microbiológicas, as quais mostram estar de acordo com a legislação vigente. Foram realizadas levantamento de custo dos produtos desenvolvidos, os quais mostram estar economicamente de acordo com produtos similares encontrados no mercado.
12

PRODUÇÃO DE ÁCIDO PROPIÔNICO A PARTIR DE EFLUENTES AGROINDUSTRIAIS

Moreira, Debora Christina 08 July 2013 (has links)
Made available in DSpace on 2017-07-21T18:53:21Z (GMT). No. of bitstreams: 1 Debora C Moreira.pdf: 799615 bytes, checksum: bf5390535b39bc8ca4f452bde2fd297b (MD5) Previous issue date: 2013-07-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The search for renewable energy and food production with the minimum threat to the environment are themes that have been studied for all over the world. Several processes have been developed for the use of agroindustrial wastes, transforming them into chemical compounds and products with high added value. The use of agroindustrial wastes in bioprocesses helps the search for sustainable processes. The increasing in the agricultural productivity in Brazil, open a new market to the development of researches that study this issue. The statistical modeling of mixtures, allied with the design of experiments, has application in a several industrial systems. The aim of this work was to study the possibility of use agroindustrial wastewater mixtures to produce propionic acid. Four types of wastewater were studied: corn steep liquor, pet food wastewater, meat processing wastewater and dairy wastewater. Assays were performed to obtain the best composition of the mixtures and the best substrate ratio. Within the conditions employed, the mixture containing 75% of corn steep liquor and 25% of another substrate, were most suitable for the process. Studying the tests in which the fermentations conditions varied (boiling the substrate, agitation and pH correction to 6,5) the best concentrations of propionic acid, 229,57 mg.L-1, were produced by mixing 75% of corn steep liquor and 25% of pet food wastewater, after 72h of fermentation, with initial correcting of pH to 6,5, followed by the mixture containing 75% of corn steep liquor and 25% of meat processing wastewater, that enabled the production of 154,27 mg.L-1 of propionic acid. The mixture with 75% of corn steep liquor and 25% of dairy wastewater with daily pH correction enabled the production of 220,96 mg.L-1 of propionic acid after 72 hours of fermentation. The other essay conditions were not significant for propionic acid biosynthesis. The statistical analysis confirms that it is possible to use codigestion agroindustrial waste for propionic acid production. / A busca por fontes de energia renovável e a produção de alimentos com a mínima ameaça ao ecossistema têm sido temas bastante pesquisados em todo o mundo. Diversos processos têm sido desenvolvidos para a utilização de resíduos agroindustriais, transformando-os em compostos químicos e produtos com alto valor agregado. A utilização de resíduos agroindustriais em bioprocessos favorece a busca por processos sustentáveis. O aumento da produtividade agrícola no Brasil abre um novo mercado para o desenvolvimento de pesquisas que abordem este tema. O planejamento estatístico de misturas, aliado à otimização de experimentos, tem aplicação em diversos sistemas industriais. O objetivo deste trabalho foi avaliar a possibilidade da utilização de misturas de efluentes agroindustriais para a produção de ácido propiônico. Foram utilizados quatro tipos de efluentes: efluente do processamento de milho, efluente do processamento de ração animal, efluente de processamento de carnes e de laticínio. Foram realizados ensaios para a obtenção da melhor composição das misturas, definindo-se a melhor proporção dos substratos. Dentro das condições empregadas, as composições contendo 75% do efluente do processamento de milho e 25% de outro substrato foram as mais adequadas ao processo. Nos ensaios onde as condições de fermentação foram variadas (fervura prévia do substrato, agitação e correção do pH para 6,5), os melhores resultados de produção de ácido propiônico, 229,57 mg.L-1, foram obtidos com substrato composto por 75% de efluente do processamento de milho mais 25% de efluente de fábrica de ração, com 72h de fermentação, correção de pH inicial para 6,5 e sem agitação, seguido de substrato com 75% de efluente do processamento de milho mais 25% de efluente de processamento de carnes, nas mesmas condições, obtendo-se produção de 154,27 mg.L-1 de ácido propiônico. O substrato contendo 75% de efluente do processamento de milho mais 25% de efluente de laticínio, possibilitou produção de 220,96 mg.L-1 de ácido propiônico, após 72 horas de fermentação e com correção de pH a cada 24 horas. As outras condições testadas não foram significativas na biossíntese de ácido propiônico. A análise estatística dos dados confirmou que é possível a utilização de codigestão de efluentes agroindustriais para a produção de ácido propiônico.
13

Fibrocimentos com gradação funcional. / Functionally graded fiber cements.

Dias, Cleber Marcos Ribeiro 25 February 2011 (has links)
O presente estudo mostra que o conceito de materiais com gradação funcional (MGF) pode ser aplicado no desenvolvimento de componentes de fibrocimento mais econômicos e com desempenho mecânico melhorado. Primeiramente, este trabalho estabelece o conceito de fibrocimento com gradação funcional. Depois, modelam-se, em elementos finitos, as tensões em telhas onduladas sob flexão estática e cargas de vento e mostra-se que, para esses tipos de carregamento, regiões específicas das telhas são submetidas a tensões de baixa intensidade justificando a aplicação do conceito de MGF para a otimização da distribuição da resistência em tais componentes. A parte experimental deste trabalho é constituída de quatro estudos: a) produção de fibrocimentos com o teor de fibras variando ao longo da espessura; b) desenvolvimento de um método de escolha de formulações para fibrocimentos com gradação funcional; c) desenvolvimento de compósitos cimentícios para extrusão em altas velocidades, destinados a gradação de fibrocimentos; e d) aplicação pré-industrial para avaliar a aplicabilidade de técnica de modificação local das propriedades de telhas com gradação funcional. Mostra-se, experimentalmente, que fibrocimentos contendo 1,0% de fibras de PVA, em massa, estrategicamente distribuídas ao longo da espessura, apresentam módulo de ruptura (MOR) similar ao dos fibrocimentos homogêneos com 1,8% de fibras, comprovando a eficácia deste tipo de gradação na redução do custo de placas de fibrocimento. O segundo trabalho experimental avalia formulações de fibrocimento constituídas de seis matérias-primas empregando-se a estratégia screening, uma metodologia promissora para gerar regras de mistura, otimizar custos e desempenho e facilitar a escolha de formulações locais para fibrocimentos com gradação funcional. Compósitos cimentícios com fibras de PVA ou vidro álcali resistente (AR), destinadas à extrusão em altas velocidades, foram desenvolvidos para aplicação pré-industrial. Aqueles contendo 4,0% de fibra de vidro, em volume, apresentaram resistência à tração média igual a 12,0 MPa, enquanto compósitos com 3,0% de fibras de PVA apresentaram resistência igual a 7,5 MPa. A aplicação destas misturas entre as camadas de telhas onduladas de fibrocimento, durante o experimento pré-industrial, resultou em melhoras substanciais do desempenho local. / The present study applies the functionally graded materials (FGM) concept on the development of fiber cements as an alternative to improve the mechanical performance and reduce cost of production of asbestos-free corrugated sheets. Primarily, this work establishes the concept of functionally graded fiber cement. Then, finite element modeling (FEM) is applied in the evaluation of the stresses distributions in corrugated sheets under bending and static wind loads. The simulations show that for these load cases, some regions of corrugated sheets are submitted to low stress intensities what justify the application of FGM concept for optimization of the strength distribution in such components. The experimental part of this work consists of four different studies: a) production of functionally graded fiber cements with gradation through thickness; b) development of a method for choosing formulations in functionally graded fiber cements; c) development of fiber reinforced cementitious composites for high speed extrusion and; d) pre-industrial application to evaluate the suitability of functionally graded fiber cements production. The first experimental study shows that functionally graded cementitious composites with 1.0% of PVA fibers, in mass, strategically distributed through thickness, presented similar modulus of ruptures (MORs) to that homogeneous ones with 1.8% of PVA fibers what proves that gradation of fiber content through thickness is a good approach to reduce cost of fiber cement pads without affecting the mechanical performance of the composite. The second experimental work examines sixcomponent fiber cement formulations employing the screening strategy which is a promising methodology to generate coherent mixture rules, optimize cost and performance and even facilitate the choosing of formulations for functionally graded fiber cements. PVA fibers and glass fiber reinforced cementitious composites for high speed extrusion were developed forpre-industrial application. Composites with 4.0% of alkali-resistant (AR) glass fiber, in volume, presented average tensile strength of 12.0 MPa while composites with 3.0% of PVA fibers presented 7.5 MPa. The application of these mixtures between layers of fiber cement corrugated sheets results in improvement of the performance of the product.
14

Fibrocimentos com gradação funcional. / Functionally graded fiber cements.

Cleber Marcos Ribeiro Dias 25 February 2011 (has links)
O presente estudo mostra que o conceito de materiais com gradação funcional (MGF) pode ser aplicado no desenvolvimento de componentes de fibrocimento mais econômicos e com desempenho mecânico melhorado. Primeiramente, este trabalho estabelece o conceito de fibrocimento com gradação funcional. Depois, modelam-se, em elementos finitos, as tensões em telhas onduladas sob flexão estática e cargas de vento e mostra-se que, para esses tipos de carregamento, regiões específicas das telhas são submetidas a tensões de baixa intensidade justificando a aplicação do conceito de MGF para a otimização da distribuição da resistência em tais componentes. A parte experimental deste trabalho é constituída de quatro estudos: a) produção de fibrocimentos com o teor de fibras variando ao longo da espessura; b) desenvolvimento de um método de escolha de formulações para fibrocimentos com gradação funcional; c) desenvolvimento de compósitos cimentícios para extrusão em altas velocidades, destinados a gradação de fibrocimentos; e d) aplicação pré-industrial para avaliar a aplicabilidade de técnica de modificação local das propriedades de telhas com gradação funcional. Mostra-se, experimentalmente, que fibrocimentos contendo 1,0% de fibras de PVA, em massa, estrategicamente distribuídas ao longo da espessura, apresentam módulo de ruptura (MOR) similar ao dos fibrocimentos homogêneos com 1,8% de fibras, comprovando a eficácia deste tipo de gradação na redução do custo de placas de fibrocimento. O segundo trabalho experimental avalia formulações de fibrocimento constituídas de seis matérias-primas empregando-se a estratégia screening, uma metodologia promissora para gerar regras de mistura, otimizar custos e desempenho e facilitar a escolha de formulações locais para fibrocimentos com gradação funcional. Compósitos cimentícios com fibras de PVA ou vidro álcali resistente (AR), destinadas à extrusão em altas velocidades, foram desenvolvidos para aplicação pré-industrial. Aqueles contendo 4,0% de fibra de vidro, em volume, apresentaram resistência à tração média igual a 12,0 MPa, enquanto compósitos com 3,0% de fibras de PVA apresentaram resistência igual a 7,5 MPa. A aplicação destas misturas entre as camadas de telhas onduladas de fibrocimento, durante o experimento pré-industrial, resultou em melhoras substanciais do desempenho local. / The present study applies the functionally graded materials (FGM) concept on the development of fiber cements as an alternative to improve the mechanical performance and reduce cost of production of asbestos-free corrugated sheets. Primarily, this work establishes the concept of functionally graded fiber cement. Then, finite element modeling (FEM) is applied in the evaluation of the stresses distributions in corrugated sheets under bending and static wind loads. The simulations show that for these load cases, some regions of corrugated sheets are submitted to low stress intensities what justify the application of FGM concept for optimization of the strength distribution in such components. The experimental part of this work consists of four different studies: a) production of functionally graded fiber cements with gradation through thickness; b) development of a method for choosing formulations in functionally graded fiber cements; c) development of fiber reinforced cementitious composites for high speed extrusion and; d) pre-industrial application to evaluate the suitability of functionally graded fiber cements production. The first experimental study shows that functionally graded cementitious composites with 1.0% of PVA fibers, in mass, strategically distributed through thickness, presented similar modulus of ruptures (MORs) to that homogeneous ones with 1.8% of PVA fibers what proves that gradation of fiber content through thickness is a good approach to reduce cost of fiber cement pads without affecting the mechanical performance of the composite. The second experimental work examines sixcomponent fiber cement formulations employing the screening strategy which is a promising methodology to generate coherent mixture rules, optimize cost and performance and even facilitate the choosing of formulations for functionally graded fiber cements. PVA fibers and glass fiber reinforced cementitious composites for high speed extrusion were developed forpre-industrial application. Composites with 4.0% of alkali-resistant (AR) glass fiber, in volume, presented average tensile strength of 12.0 MPa while composites with 3.0% of PVA fibers presented 7.5 MPa. The application of these mixtures between layers of fiber cement corrugated sheets results in improvement of the performance of the product.
15

Mixture Design Response Surface Methodology Analysis of Seven Natural Bioactive Compounds to Treat Prostate Cancer

Berlin, Ian Geddes 15 December 2021 (has links)
Natural bioactive compounds have drawn the interest of many researchers worldwide in their effort to find novel treatments, including prostate cancer (PC) treatment which is estimated to be 13.1% of all new cancer cases in the U.S. in 2021. Many of these bioactive compounds have been identified from treatments in traditional Chinese medicine (TCM), that often have multiple bioactive compounds present. However, in vitro studies frequently focus on the compounds in isolation, or in simple combinations of two compounds. We used mixture design response surface methodology (MDRSM) to assess changes in PC cell viability after 48 hours of treatment to identify the optimal mixture of all 35 three-compound combinations of seven bioactive compounds from TCM. We used Berberine, Wogonin, Shikonin, Curcumin, Triptolide, Emodin, and Silybin to treat PC-3, DU145, and LNCaP human PC cells, and a drug-resistant PC-3 cell line. Berberine and Wogonin most frequently contributed to the optimal combination to reduce cell viability in PC-3 and LNCaP cells; DU145 cells more frequently responded best to a single compound.
16

Contribution de la planification expérimentale à la modélisation de phénomènes complexes en formulation / Experimental designs for complex phenomena in formulation

Gomes, Charles 20 December 2018 (has links)
Dans certains domaines de la formulation, comme la cosmétique, les phénomènes étudiés peuvent être très chaotiques avec des zones de rupture ou de non linéarité. Dans ce cas, le formulateur doit se poser de nombreuses questions avant de proposer la stratégie expérimentale optimale qui doit être adaptée au mieux à son problème. Pour de tels phénomènes, des plans d'expériences classiques, tels que les réseaux de Scheffé ou les plans D-optimaux, se révèlent insuffisants car les points expérimentaux ne couvrent pas uniformément l'espace expérimental. En effet, il est intéressant dans ces cas d'étude d'explorer l'ensemble du domaine expérimental et de répartir uniformément les points dans l'espace. Pour cela, les plans uniformes ou Space-Filling Designs (SFD), fréquemment utilisés dans le cas de variables orthogonales, mais très peu dans le cas des variables de mélange, sont particulièrement intéressants. L'objectif de cette thèse est d’adapter des algorithmes de construction de plans uniformes dans le cas de plans de mélanges, de proposer des règles simples pour aider au choix de la nature et du nombre de points du plan d'expériences de mélange / In some domains of formulation, as cosmetics, the phenomena can be very chaotic with discontinuities or not linear zones. In the cosmetic field, the formulator has to propose the optimal experimental strategy which must be well adapted to the constraints imposed by the experimenters. For such phenomena, classical designs of experiments, such as Scheffé simplexes lattices or the D-optimal designs, are proving insufficient because the experimental points do not uniformly cover the experimental space. Indeed, it is essential in these studies to explore the whole experimental domain and to uniformly distribute points in the space. For that purpose, the Space-Filling Designs (SFD), frequently used in the case of orthogonal variables, but less in the case of the mixture variables, are particularly interesting. The objective of this thesis is to adapt the algorithms for construction of uniform designs in the case of mixture designs and to propose guidelines for the choice of the nature and the number of points of the experimental design
17

Utredning av tillverkningsinducerade avvikelser i fiberförstärkt komposit genom blandningsexperiment : En fallstudie enligt DMAIC vid ABB Composites

Larsson Turtola, Simon, Rönnbäck, Adam January 2020 (has links)
Tillämpningen av fiberförstärkt polymerkomposit har senaste decenniet ökat kraftigt inom flertalet högteknologiska branscher. Trots framgången är förekomsten av tillverkningsinducerade avvikelser fortfarande en utmaning. Avvikelserna försämrar materialets mekaniska egenskaper och förkortar dess livslängd, vilket orsakar kassationer, miljöbelastningar och försvårad produktetablering för industriaktörer. ABB Composites i Piteå står inför en liknande situation. Företaget producerar cylindriska isolatorer i fiberförstärkt komposit till högspänningsindustrin, och behöver utreda förekomsten av en specifik avvikelse, som under senaste tre åren medfört omfattande kvalitetsbristkostnader. Produkten tillverkas genom vakuuminjicering där en hartsblandning impregnerar en glasfiberform, för att sedan övergå från flytande till fast form genom en exoterm reaktion. Hartsblandningens reaktionsförlopp har länge misstänkts påverka avvikelsernas förekomst, men har inte bekräftats, på grund av flera svårkontrollerade egenskaper. Examensarbetets syfte har därför varit att utreda om hartsblandningens egenskaper påverkar förekomsten av tillverkningsinducerade avvikelser vid tillverkning av cylindriska isolatorer. Arbetet har bedrivits som ett Sex Sigma-projekt enligt problemlösningsmetodiken DMAIC. Ett blandningsexperiment med sex komponenter genomfördes i laborationsmiljö där en datagenererad design med 36 delförsök tillämpades, varav sex stycken egenskaper hos hartsblandningen undersöktes. Experimentet påvisade att samtliga egenskaper var möjliga att styra genom att förändra proportionerna av ingredienserna. Däremot visade sig flera av egenskaperna vara korrelerade och kan därav inte justeras oberoende av varandra. Kunskapen användes till att utveckla och testa två nya varianter av hartsblandningen vid tillverkning av cylindriska isolatorer. Resultatet bekräftade att hartsblandningens egenskaper signifikant påverkar förekomsten av tillverkningsinducerade avvikelser. En viss kombination av egenskaperna som kännetecknade ett långsamt reaktionsförlopp minskade förekomsten av avvikelser på isolatorerna med 99.3 procent i jämförelse med den ordinarie hartsblandningen. Förbättringen förväntas medföra betydelsefulla besparingar, ökad konkurrenskraft och förhöjd kvalitetsmedvetenhet för ABB Composites. Examensarbetets kunskapsbidrag anses också betydelsefullt för kompositindustrin i strävan mot fortsatt reducering av tillverkningsinducerade avvikelser. / The application of fibre-reinforced polymer composites (FRPC) have during the last decades increased in many high-tech industries. Despite the success, the existence of manufacturing-induced deviations has been a long-standing challenge. These deviations affect the lifetime and the mechanical properties of the composite, which in turn lead to scrap of products and environmental impact, obstructing market exploitation for industry stakeholders. ABB Composites in Piteå is facing a similar scenario. The company produces cylindrical insulators in fibre-reinforced composite for the high-voltage industry and need to investigate a specific deviation, which has caused extensive costs during the last three years. The product is manufactured through vacuum assisted resin transfer molding (VARTM), where a resin blend impregnates a fibreglass preform, as the resin cures and transforms from liquid to solid form through an exothermic reaction. One suspected cause for the deviation has been the curing process of the resin. However, it is dependent on several difficult-to-control characteristics and is yet to be confirmed. The purpose of this thesis has therefore been to investigate whether the characteristics of the resin blend affects the occurrence of manufacturing-induced deviations while producing cylindrical insulators. The work has been conducted as an internal Six Sigma-project following the DMAIC improvement cycle. A mixture experiment with six components was performed, using a computer-generated design with 36 runs, in which six characteristics of the resin blend were examined. The experiment proved that all characteristics could be controlled by changing the proportions of the design factors. However, many of the characteristics were correlated, implying that the characteristics cannot be independently controlled. The knowledge from the experiment were used to develop two new resin blends, which were infused to cylindrical insulators in regular production environment. The result confirmed that the characteristics of the resin blend significantly affects the quality of the insulator. One of the blends, which represented a slower curing process, reduced the deviations by 99.3 percent in relation to the original blend. The improvement is expected to generate substantial savings, increased competitiveness and enhanced quality awareness for ABB Composites. Possible contributions to the industry are related to the development of a method to experimentally investigate the resin blend with the objective of reducing manufacturing-induced deviations.
18

Application of Mixture Design Response Surface Methodology for Combination Chemotherapy in PC-3 Human Prostate Cancer Cells

Oblad, Richard Vernon 01 April 2018 (has links)
Combining chemotherapeutics to treat malignant tumors has been shown to be effectivein preventing drug resistance, tumor recurrence, and reducing tumor size. We modeledcombination drug therapy in PC-3 human prostate cancer cells using mixture design responsesurface methodology (MDRSM), a statistical technique designed to optimize compositions thatwe applied in a novel manner to design combinations of chemotherapeutics. Conventionalchemotherapeutics (mitoxantrone, cabazitaxel, and docetaxel) and natural bioactive compounds(resveratrol, piperlongumine, and flavopiridol) were used in twelve different combinationscontaining three drugs at varying concentrations. Cell viability and cell cycle data werecollected and used to plot response surfaces in MDRSM that identified the most effectiveconcentrations of each drug in combination. MDRSM allows for extrapolation of data fromthree or more compounds in variable ratio combinations, unlike the Chou-Talalay method.MDRSM combinations were compared with combination index data from the Chou-Talalaymethod and were found to coincide. We propose MDRSM as an effective tool in devisingcombination treatments that can improve treatment effectiveness, and increase treatmentpersonalization because MDRSM measures effectiveness rather than synergism, potentiation orantagonism.
19

Modern design of experiments methods for screening and experimentations with mixture and qualitative variables

Chantarat, Navara 06 November 2003 (has links)
No description available.
20

Estudo laboratorial de misturas asfálticas a quente utilizadas em Goiás / Laboratorial study of hot mix asphalt used in middle west region of Brazil

Prudente, Carolina Queiroz Arantes 28 August 2015 (has links)
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No. of bitstreams: 2 Dissertação - Carolina Queiroz Arantes Prudente - 2015.pdf: 2676423 bytes, checksum: 95fa022b3853b805c569eb33d3d481e4 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) Previous issue date: 2015-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Flexible or asphalt pavements compose the Brazilian highway network, which have to promote security on traffic on the highways, to support the effects of changes in climate and to resist the traffic of vehicles. By this reasons, the structure of the pavement is particularly important and must be constituted by layers, which can distribute the loads into the structure, reducing the vertical load produced by the action of traffic and, consequently, providing protection to the subgrade. In the middle western Brazil, in the state of Goiás, there is not advanced studies on asphalt mixtures used in highways and in urban pavements, and there is not a technical scientific proofing that the local aggregates available in the region, is the best option considering the local conditions. Forward better conditions of infrastructure, it is proposed to develop more efficient asphalt mixtures for pavements, by submitting the mixtures through analysis of mechanical strength and performance test, analyzing if the most used asphalts mixtures are satisfactory or not. The hot asphalt mixture are composed by aggregates and asphalt binders that are design in order to attend the parameters set in the projects according to demand and traffic types. In this research, it was proposed the study of six asphalt mixture design with different types of asphalt binders with the same aggregates origin in a different grain size range (Bands B and C). The binders used in this study are the conventional cement asphalt in the region, CAP 30/45 e 50/70 (Brazilian penetration grade), with low and medium penetration, respectively, and the polymer modified asphalt (AMP). The CAP 50/70 is the most used conventional binder in the region, followed by CAP 30/45. Tha AMP binder is not often used. The characterization tests of the materials that composed the mixture are presented and their selection and characterization attended the standardized procedures and requirements by the brazilian department responsible for highway structures (DNIT). In a second stage, the design tests were performed, combining aggregates and binders in different rates, by the Marshall Mix Design Method using manual compression, until the great design was obtained The laboratory tests were realized with this great design to analyze the mass loss and obtain its mechanical properties, given by the tensile strength (RT). Performance tests were realized to obtain its resilient modulus (MR) and, using wheel tracking test, to obtain the permanent deformation (DP). The results showed that the common hot mixture asphalt used in the region (range C and CAP 50/70), is not a good option, because its performance is not satisfactory. Therefore, the range to be used, and the binder, must be analyzed for each traffic level. It is also recommended to evaluate the Marshall methodology for design mixtures, considering mainly the compression way and the determination of the maximum densities. / A malha rodoviária brasileira é composta, principalmente, por pavimentos do tipo flexível ou asfáltico, que devem, para promover a segurança ao tráfego nas rodovias, suportar os efeitos das mudanças de clima e resistir ao fluxo de veículos. Para isso, a estrutura do pavimento é particularmente importante e deve ser constituída por camadas que distribuam as cargas a que estão submetidas, minimizando os esforços verticais produzidos pela ação do tráfego e, consequentemente, oferecendo proteção ao subleito. Em busca de melhores condições de infraestrutura no estado de Goiás, propôs-se avaliar se as misturas asfálticas mais utilizadas na região são consideradas satisfatórias ou não, visto que inexistem estudos desenvolvidos sobre o assunto. As misturas asfálticas a quente são compostas de agregados e ligantes, que são dosados de forma a atender os parâmetros determinados nos projetos de acordo com a demanda e tipos de tráfego. Nesta pesquisa, foi proposto o estudo da dosagem de seis projetos de misturas, com diferentes tipos de ligantes asfálticos para agregados de mesma origem nas faixas granulométricas mais utilizadas na região (Faixas B e C). Foram utilizados ligantes convencionais CAP 30/45 e 50/70, com baixa e média penetração, respectivamente, e asfalto modificado com polímero (AMP). Dos ligantes convencionais, o CAP 50/70 é o mais utilizado na região, seguido do CAP 30/45, já o AMP ainda não é frequentemente utilizado. Foram realizados ensaios de caracterização dos materiais que compõem as misturas, que seguiram os procedimentos e requisitos normatizados pelo Departamento Nacional de Infraestrutura de Transportes (DNIT). Em uma segunda etapa, foram realizados ensaios de dosagem, combinando agregados e ligantes em diferentes taxas até que, por meio da metodologia Marshall com compactação manual, fosse obtida a dosagem considerada ótima para cada mistura estudada. Com essas dosagens, foram realizados ensaios em laboratório, para análise de desgaste, de desempenho das misturas e de suas propriedades mecânicas, por meio da determinação da resistência à tração por compressão diametral, do módulo de resiliência e da deformação permanente. Os resultados obtidos demonstraram que a mistura asfáltica mais comum de ser utilizada como camada de rolamento na região (Faixa C e CAP 50/70) não apresenta comportamento satisfatório. Dessa forma, a faixa granulométrica a ser utilizada deve ser repensada, bem como o tipo de ligante a ser utilizado para cada nível de tráfego. Recomenda-se, também, a reavaliação da utilização da metodologia Marshall para dosagem das misturas, principalmente na questão da forma de compactação e na determinação das densidades máximas.

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