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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.
81

Elaboration de matelas à base de fibres de verre par voie humide / Production of glass fibre-based mats by a wet-laid process

Lozano, Flavien 11 January 2019 (has links)
Les matelas fibreux à base de fibres de verre produits par voie humide ont des applications industrielles en tant que séparateur de batterie et matériaux d’isolation (cœur de panneaux d’isolation sous vide). Ces matériaux utilisent principalement des fibres submicroniques, relativement chères et pouvant présenter des risques pour la santé. Ce projet est une contribution à l'élaboration d'un procédé de fabrication par voie humide de matelas de fibres de verre visant à valoriser des fibres plus grossières, le produit final devant respecter un cahier des charges précis. Nous avons été amenés à étudier le comportement des fibres de verre dans les différentes étapes du procédé et à caractériser les matelas résultants. Nous nous sommes intéressés en particulier au comportement physico-chimique des suspensions aqueuses de fibres de verre. Nous avons caractérisé les propriétés de contexture, la résistance mécanique en traction, la compressibilité et la conductivité thermique des matelas fibreux. Les travaux expérimentaux nous ont permis de proposer une formulation de la composition optimisée et des conditions opératoires du procédé afin que le matelas final soit conforme au cahier des charges. Cette nouvelle composition intègre des fibres de renfort en faible quantité. Elle permet d’améliorer les caractéristiques mécaniques sans affecter les autres propriétés.Enfin, nous avons quantifié les coûts de production et les avons comparés à ceux du procédé actuellement utilisé avec des fibres grossières (production par voie sèche).Mots-clés : Génie papetier, physico-chimie, milieu poreux, fibres de verre, caractérisation. / Glass fibre - based mats produced by a wetlaid process have industrial applications as a battery separator and insulation materials (core of vacuum insulation panels). These materials are mainly made with sub-micron fibres which relatively expensive and can present a risk to health. This project is a contribution to the production of glass fibre-based mats by a wet-laid process to add value to coarser fibres, the final product should respect precise specifications. We have been led to study the behavior of glass fibers in different stages of the process and to characterize the resulting mats. We investigated especially the physico-chemical behavior of aqueous suspensions of glass fiber. We have characterized structure properties, the mechanical resistance to traction, the compressibility and the thermal conductivity of fibrous mats. The experimental work has allowed us to give a formulation of the optimized composition and operational conditions of the process so that the final mattress conforms to the specifications. This new composition includes reinforcement fibres in small quantities. It allows improving the mechanical characteristics without affecting the other properties. Finally, we quantified the production costs and compared them to those of the process currently used with coarse fiber (dry-laid production).Keywords: Paper engineering, physical chemistry, porous media, glass fibre, characterization.
82

Composição físico-química e nutricional do mel adicionado com própolis / Physico-chemical composition and nutritional of the honey added with propolis

Bera, Alexandre 04 May 2004 (has links)
O presente estudo teve, como objetivo principal, a determinação da composição físico-química e nutricional de onze amostras de méis com própolis comercializados no Estado de São Paulo, de acordo com as metodologias analíticas da legislação brasileira vigente (Instrução Normativa nº11 de 20 de outubro de 2000), que segue os métodos preconizados pelos Codex Alimentarius Commission (CAC), 1990 e Association of Official Analytical Chemists (AOAC), 1990). Amostras de mel puro e de própolis foram usadas como referência. Os resultados mostraram que os mesmos métodos usados para o controle de qualidade do mel puro (umidade, HMF, açúcares redutores, sacarose aparente, cinzas, acidez livre, sólidos insolúveis em água) foram adequados para o controle de qualidade do mel com própolis, exceto pela analise de atividade diastásica, que precisou de uma adaptação metodológica. A análise de minerais demonstrou que essas amostras não são fontes de ferro, magnésio, zinco e cálcio. A própolis adicionada ao mel aumentou o seu valor energético comparado com o mel puro. Cinco das onze amostras analisadas não apresentaram, na sua rotulagem, os valores nutricionais como recomenda a legislação. É indicada a necessidade de uma fiscalização mais rigorosa, assim como uma legislação específica para o controle de qualidade destes produtos. / The present work has, as its main objective, to determine the physico-chemical and nutritional composition of commercial samples of propolis added to honey from São Paulo State. Eleven honey-propolis samples were analyzed, according to the methods established by the Brazilian Law (Instrução Normativa n.11 de 20 de outubro de 2000) which recommends the same methods established by Codex Alimentarius Commission (CAC) and the Association of Official Analytical Chemists (AOAC, 1990). The results showed that the same methods used for pure honey quality control (moisture, HMF, reducing sugars, apparent sucrose, ash, free acidity, insoluble solids in water) except for the diastase activity which had to be adapted, can also be used for the honey-propolis quality control. The mineral analyses results showed that the samples were not a good source for iron, magnesium, zinc and calcium. Honey has its energy value enhanced by the addition of propolis if compared with pure honey. As five of the eleven samples analyzed did not have the nutritional values information on the labels as it is mandatory by the Brazilian Legislation, a more rigorous inspection and even a specific law should be established for the quality control of those products.
83

Avaliação da presença de cianobactérias em efluentes de sistema de tratamento de esgotos sanitários por lagoas de estabilização associadas a tratamento físico-químico. / Evaluation of the presence of cyanobacteria in wastewater treatment system throught stabilization ponds associated with physicochemical treatment.

Godoy, Osvaldo Americano 28 September 2007 (has links)
A presente pesquisa propôs avaliar a presença de cianobactérias, tanto quantitativamente como qualitativamente e clorofila-a quantitativamente, em relação à legislação CONAMA Nº 357/05, em um sistema de tratamento de lagoas de estabilização com pré e pós-tratamento físico-químico, além de avaliar o comportamento de parâmetros convencionais, como Demanda Bioquímica de Oxigênio (DBO), Demanda Química de Oxigênio (DQO), Nitrogênio amoniacal (NNH3), Fósforo (P), Sólidos Suspensos Totais (SST), Potencial Hidrogeniônico (pH). Para tanto, utilizou-se a Estação de Tratamento de Efluentes da Riviera de São Lourenço - Bertioga - SP, para o estudo em questão, onde o sistema é composto de Tratamento primário quimicamente assistido (TPQA) com aplicação de produtos químicos (polímero como coagulante), seguido de duas lagoas facultativas, lagoa de maturação, Decantador de algas (decantador) com aplicação de produtos químicos (polímero e cal hidratada) e tanque de contato de cloro. Utilizou-se um período de estudo de nove meses (Outubro/2005 à Junho/2006), com coletas e análises semanais e quinzenais, dos efluentes das lagoas facultativas, da lagoa de maturação, do Decantador de algas e final do sistema. As análises foram realizadas no Laboratório de Controle Ambiental da Riviera de São Lourenço. Foram encontradas ao longo do sistema as seguintes espécies de cianobactérias: Planktothrix sp, Merismopedia sp, Microcystis sp, Phormidium sp, Chroococcus sp, Pseudonabaena sp, Aphanocapsa sp. Ao longo de todo o período, as maiores presenças de espécies foram de Planktothrix sp. e Merismopedia sp. Encontrou-se os seguintes valores ao longo do sistema para densidades de cianobactérias na baixa temporada: para lagoas facultativas - 18880 cel/mL; lagoa de maturação - 16350 cel/mL; Decantador de algas - 4680 cel/mL; saída do sistema - 6400 cel/mL; e na alta temporada: para lagoas facultativas - 26340 cel/mL; lagoa de maturação - 13170 cel/mL; Decantador de algas - 11840 cel/mL; saída do 1 sistema - 2910 cel/mL. As densidades de cianobactérias encontradas na baixa e alta temporada na saída do tratamento refletem valores sempre abaixo em relação à nova legislação CONAMA Nº 357/05 no que tange os limites de cianobactérias para águas classes I, II e III. As concentrações de clorofila-a no efluente da lagoa de maturação resultaram em 432 ±182?g/L, e 268 ± 185?g/L no efluente final do sistema. A eficiência de remoção foi de 53 ± 28%,. Estes resultados de clorofila-a para este sistema de tratamento de esgotos com as novas mudanças, ou seja, o sistema biológico precedido e sucedido por tratamento físico-químico, podem ser considerados satisfatórios, mas são mais elevados que os limites preconizados na Resolução CONAMA Nº 357/05 para águas classes I, II e III, havendo a necessidade se contar com algum grau de diluição para permitir o enquadramento. Para os parâmetros convencionais analisados ao longo do período, destacam-se as concentrações no efluente final de fósforo de 5 ± 2 mgP/L e de nitrogênio amoniacal de 22 ± 10 mgN/L. Com relação ao fósforo, observa-se a necessidade de diluição no corpo receptor para o enquadramento às classes mais restritivas e, com relação ao nitrogênio amoniacal, verifica-se que o valor médio é superior ao padrão de lançamento de 20 mgN/L estabelecido pela Resolução 357/2005 do CONAMA. / The present research proposes to evaluate the presence of cyanobacteria either quantitatively and qualitatively, as well as chlorophyll-a quantitatively, according to CONAMA Nº 357/05 legislation, for a stabilization ponds treatment system associated with physico-chemical treatment, as well as evaluating typical parameters behavior, such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Nitrogen (N), Phosphorus (P), Total Suspended Solids (TSS), power hydrogen (pH). For the research, It has been used the Riviera de São Lourenço effluent treatment station in Bertioga - SP, where the system includes an Chemical enhanced Primary Treatment (CEPT) with application of chemicals products (polymer with coagulant), followed by two Facultative ponds, maturation pond, Algae Removal (decanter) with application of chemical components (polymer and hydrated lime) and chlorine chicane. It has taken a period of 9 months (oct/2005 to jun/2006), with both weekly and fortnight sample and analysis, and the observed spots were the facultative pond output, maturation pond output, algae remover output and system output. The analyses were made by Riviera de São Lourenço environmental control laboratory, when the following sorts of cyanobacteries have been found: Planktothrix sp, Merismopedia sp, Microcystis sp, Phormidium sp, Chroococcus sp, Pseudonabaena sp, Aphanocapsa sp. During the whole period, the major presence of species detected were Planktothrix sp.(100%) and Merismopedia sp.(71%). The following values for cyanobacteria density were found at low season: facultative ponds - 18880 cel/mL; maturation pond - 16350 cel/mL; algae removal - 4680 cel/mL; system output - 2910 cel/mL. The cyanobacdteria density found during low 1 and high season at the system output always under the new legislation CONAMA Nº 357/05, according the cyanobacteria limits for I, II and III classes of water. The chlorophyll-a concentration on the maturation pond´s effluent and system output showed 432 ± 182?g/L and 268 ± 185?g/L, respectively. The removal efficiency was 53 ± 28%. These chlorophyll-a results for that wastewater system, with the improvements, were satisfatory, but higher than the legislation´s limits for I, II and III water classes before the dilution computation. For the conventional parameters analysed during the whole period, phosphorus concentrations at the system output were 5 ± 2 mgP/L and total nitrogen 22 ± 10 mgN/L are showed up. It was observed that is necessary the dilution computation for phosphorus for accordance to legislation and for total nitrogen it was verified that the mean value is higher than de limit of 20mgN/L, according to legislation CONAMA 357/2005.
84

Avaliação das condições higienicossanitárias e análise de parâmetros microbiológicos e físico-químicos do pescado importado no Porto de Santos/SP / Evaluation of hygienic sanitary conditions and analysis of microbiological and physico-chemical parameters of imported fish in the Santos/SP port

Castro, Adriano Perrelli Pestana de 09 February 2017 (has links)
Introdução - O pescado é amplamente utilizado para a produção de alimentos à base de matéria-prima de origem animal. A importação de pescado vem crescendo ano a ano, sendo o Porto de Santos/SP uma das principais rotas de entrada desse produto no país. Objetivos - Avaliar as condições higienicossanitárias de pescado importado no Porto de Santos/SP. Métodos - A pesquisa foi desenvolvida com base em duas abordagens: estudo dos requisitos obrigatórios para nacionalização do produto importado com base na legislacão vigente e trabalho desempenhado pelo Vigiagro/MAPA, assim como, estudo laboratorial. Foram coletadas 60 amostras de 30 diferentes produtos de pescado sendo cada amostra constituída por, no mínimo, 500 g do produto de uma mesma marca, lote, data de fabricação e validade. Uma parte das amostras, 30 embalagens de 500 g no mínimo, foi acondicionada em caixas isotérmicas com temperatura controlada e encaminhada para realização das análises microbiológicas. As demais 30 embalagens foram encaminhadas, sob as mesmas condições, para realização das análises físico-químicas. As análises físico-químicas e microbiológicas foram realizadas em Laboratórios credenciados no Mapa. Para produtos congelados foram realizadas as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas e contagem de Staphylococcus coagulase positiva e realização das análises físico-químicas de N-BVT. Para produtos salgados refrigerados, foram realizadas análises microbiológicas para pesquisa de Salmonella spp em 25 gramas, contagem de Staphylococcus coagulase positiva e contagem de coliformes termotolerantes a 450 C, assim como, realização das análises físico-químicas de umidade e resíduo mineral fixo. Resultados - Nos produtos congelados, as análises físico-químicas para o N-BVT e as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas e contagem de Staphylococcus coagulase positiva indicaram 100,0% de conformidade com a legislação vigente. Nos produtos salgados refrigerados, as análises microbiológicas para pesquisa de Salmonella spp em 25 gramas, contagem de Staphylococcus coagulase positiva e contagem de coliformes termotolerantes a 450 C também indicaram 100,0% de conformidade com a legislação vigente. Por outro lado, 100,0% das análises físico-química de umidade e 44,4% das análises físico-químicas para resíduo mineral fixo no pescado salgado resfriado estavam com valores acima da legislação vigente. Todos os produtos apresentaram documentação obrigatória e rótulo de acordo com a legislação vigente. Conclusão Embora os resultados das análises microbiológicas tenham demonstrado que os produtos estivessem próprios para o consumo, as análises físico-químicas, em específico os parâmetros referentes a umidade no pescado salgado refrigerado, não estavam de acordo com os valores determinados pela legislação vigente. A legislação sanitária vigente para importação de pescados, assim como a metodologia de inspeção e fiscalização desses produtos, se mostrou eficiente comparado aos resultados laboratoriais encontrados, com possibilidade de inclusão de novas ferramentas e análises laboratoriais visando garantir, ainda mais, as condições higiênicossanitárias e segurança alimentar. / Introduction - Seafood is widely used for the production of food based on raw materials of animal origin. The fish import has been growing year by year, and the Port of Santos / SP one of the main routes of entry of that product in the country. Objectives - To evaluate the hygienic-sanitary conditions of imported fish in the Port of Santos / SP. Methodology - The study was based up on two approaches: study of the mandatory requirements for nationalization of the imported product on the basis of current legislation and work performed by Vigiagro / MAPA, as well as laboratory study. It was collected 60 samples from 30 different products of fish each sample being composed by 500 g from the same brand, batch number, manufacturing and expiration date. A share of these samples, 30 packages of 500 g at least, was accommodated and transported in temperature-controlled isothermal box to the microbiological analysis. The remaining 30 packages were sent, under the same conditions, to physico-chemical analysis. The physico-chemical and microbiological analyzes were performed in laboratories accredited on MAPA. For frozen products were performed microbiological analyzes for Salmonella spp research in 25 g Staphylococcus and count coagulase positive and achievement of physical and chemical analysis of N-BVT. For salted products, microbiological analyzes were performed for detection of Salmonella spp in 25 g, Staphylococcus coagulase positive count and count of coliform to 450 C and physical-chemical analysis for humidity and fixed mineral residue. Results - In the frozen products, physico-chemical analysis for the N-BVT and microbiological analyzes for Salmonella spp research in 25 g and Staphylococcus coagulase positive counts indicated 100.0% of compliance with current regulation. In salted products, microbiological analyzes for Salmonella spp research in 25 g, Staphylococcus coagulase positive and coliform to 450 C counts also indicated 100.0% compliance with current legislation. On the other, 100.0% of the physico-chemical analysis of humidity and 44,4 % in the ashs physico-chemical results, in salted fish, were with higer limits established by Brazilian legislation. All products submitted mandatory documents required for import and labeling in accordance with current regulation. Conclusion - Although the results of the microbiological analyzes showed that the imported fish were apropriate for consumption, the physico-chemical analysis, in particularly the humidity parameters were not in accordance with values indicated in the current regulation. The current health regulation for the imported fish, as well as the inspection methodology and supervision of these products, was efficient compared to laboratory findings, with the possibility of adding new tools and laboratory tests to ensure even more the higienic-sanitary conditions and food safety.
85

Avaliação da presença de cianobactérias em efluentes de sistema de tratamento de esgotos sanitários por lagoas de estabilização associadas a tratamento físico-químico. / Evaluation of the presence of cyanobacteria in wastewater treatment system throught stabilization ponds associated with physicochemical treatment.

Osvaldo Americano Godoy 28 September 2007 (has links)
A presente pesquisa propôs avaliar a presença de cianobactérias, tanto quantitativamente como qualitativamente e clorofila-a quantitativamente, em relação à legislação CONAMA Nº 357/05, em um sistema de tratamento de lagoas de estabilização com pré e pós-tratamento físico-químico, além de avaliar o comportamento de parâmetros convencionais, como Demanda Bioquímica de Oxigênio (DBO), Demanda Química de Oxigênio (DQO), Nitrogênio amoniacal (NNH3), Fósforo (P), Sólidos Suspensos Totais (SST), Potencial Hidrogeniônico (pH). Para tanto, utilizou-se a Estação de Tratamento de Efluentes da Riviera de São Lourenço - Bertioga - SP, para o estudo em questão, onde o sistema é composto de Tratamento primário quimicamente assistido (TPQA) com aplicação de produtos químicos (polímero como coagulante), seguido de duas lagoas facultativas, lagoa de maturação, Decantador de algas (decantador) com aplicação de produtos químicos (polímero e cal hidratada) e tanque de contato de cloro. Utilizou-se um período de estudo de nove meses (Outubro/2005 à Junho/2006), com coletas e análises semanais e quinzenais, dos efluentes das lagoas facultativas, da lagoa de maturação, do Decantador de algas e final do sistema. As análises foram realizadas no Laboratório de Controle Ambiental da Riviera de São Lourenço. Foram encontradas ao longo do sistema as seguintes espécies de cianobactérias: Planktothrix sp, Merismopedia sp, Microcystis sp, Phormidium sp, Chroococcus sp, Pseudonabaena sp, Aphanocapsa sp. Ao longo de todo o período, as maiores presenças de espécies foram de Planktothrix sp. e Merismopedia sp. Encontrou-se os seguintes valores ao longo do sistema para densidades de cianobactérias na baixa temporada: para lagoas facultativas - 18880 cel/mL; lagoa de maturação - 16350 cel/mL; Decantador de algas - 4680 cel/mL; saída do sistema - 6400 cel/mL; e na alta temporada: para lagoas facultativas - 26340 cel/mL; lagoa de maturação - 13170 cel/mL; Decantador de algas - 11840 cel/mL; saída do 1 sistema - 2910 cel/mL. As densidades de cianobactérias encontradas na baixa e alta temporada na saída do tratamento refletem valores sempre abaixo em relação à nova legislação CONAMA Nº 357/05 no que tange os limites de cianobactérias para águas classes I, II e III. As concentrações de clorofila-a no efluente da lagoa de maturação resultaram em 432 ±182?g/L, e 268 ± 185?g/L no efluente final do sistema. A eficiência de remoção foi de 53 ± 28%,. Estes resultados de clorofila-a para este sistema de tratamento de esgotos com as novas mudanças, ou seja, o sistema biológico precedido e sucedido por tratamento físico-químico, podem ser considerados satisfatórios, mas são mais elevados que os limites preconizados na Resolução CONAMA Nº 357/05 para águas classes I, II e III, havendo a necessidade se contar com algum grau de diluição para permitir o enquadramento. Para os parâmetros convencionais analisados ao longo do período, destacam-se as concentrações no efluente final de fósforo de 5 ± 2 mgP/L e de nitrogênio amoniacal de 22 ± 10 mgN/L. Com relação ao fósforo, observa-se a necessidade de diluição no corpo receptor para o enquadramento às classes mais restritivas e, com relação ao nitrogênio amoniacal, verifica-se que o valor médio é superior ao padrão de lançamento de 20 mgN/L estabelecido pela Resolução 357/2005 do CONAMA. / The present research proposes to evaluate the presence of cyanobacteria either quantitatively and qualitatively, as well as chlorophyll-a quantitatively, according to CONAMA Nº 357/05 legislation, for a stabilization ponds treatment system associated with physico-chemical treatment, as well as evaluating typical parameters behavior, such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Nitrogen (N), Phosphorus (P), Total Suspended Solids (TSS), power hydrogen (pH). For the research, It has been used the Riviera de São Lourenço effluent treatment station in Bertioga - SP, where the system includes an Chemical enhanced Primary Treatment (CEPT) with application of chemicals products (polymer with coagulant), followed by two Facultative ponds, maturation pond, Algae Removal (decanter) with application of chemical components (polymer and hydrated lime) and chlorine chicane. It has taken a period of 9 months (oct/2005 to jun/2006), with both weekly and fortnight sample and analysis, and the observed spots were the facultative pond output, maturation pond output, algae remover output and system output. The analyses were made by Riviera de São Lourenço environmental control laboratory, when the following sorts of cyanobacteries have been found: Planktothrix sp, Merismopedia sp, Microcystis sp, Phormidium sp, Chroococcus sp, Pseudonabaena sp, Aphanocapsa sp. During the whole period, the major presence of species detected were Planktothrix sp.(100%) and Merismopedia sp.(71%). The following values for cyanobacteria density were found at low season: facultative ponds - 18880 cel/mL; maturation pond - 16350 cel/mL; algae removal - 4680 cel/mL; system output - 2910 cel/mL. The cyanobacdteria density found during low 1 and high season at the system output always under the new legislation CONAMA Nº 357/05, according the cyanobacteria limits for I, II and III classes of water. The chlorophyll-a concentration on the maturation pond´s effluent and system output showed 432 ± 182?g/L and 268 ± 185?g/L, respectively. The removal efficiency was 53 ± 28%. These chlorophyll-a results for that wastewater system, with the improvements, were satisfatory, but higher than the legislation´s limits for I, II and III water classes before the dilution computation. For the conventional parameters analysed during the whole period, phosphorus concentrations at the system output were 5 ± 2 mgP/L and total nitrogen 22 ± 10 mgN/L are showed up. It was observed that is necessary the dilution computation for phosphorus for accordance to legislation and for total nitrogen it was verified that the mean value is higher than de limit of 20mgN/L, according to legislation CONAMA 357/2005.
86

Influência do protocolo de secagem com álcool isopropílico na adesividade de diferentes cimentos obturadores de metacrilato à dentina radicular / Influence of the drying protocol with isopropyl alcohol on the adhesion of different methacrylate-based sealers to intraradicular dentin

Dias, Kleber Campioni 12 April 2012 (has links)
O presente estudo teve como objetivo avaliar a influência do protocolo de secagem com álcool isopropílico à adesividade dos cimentos AH Plus, Hybrid Root Seal e Epiphany SE à dentina radicular. Oitenta raízes de caninos foram submetidas ao preparo biomecânico e distribuídas em 2 grupos de acordo com a secagem, previamente a obturação: I- Secagem cone de papel absorvente e II- Secagem com álcool isopropílico 70%,e posteriormente distribuídas em 8 grupos (n=10): IA e IIA cimento AH Plus; IB e IIB - cimento Hybrid Root Seal; IC e IIC- cimento Epiphany SE com guta percha e ID e IID cimento Epiphany SE com Resilon. Após a obturação, 80 raízes foram seccionadas transversalmente obtendo-se 3 slices de 1,0 mm de espessura para cada terço radicular. Um slice de cada terço foi submetido ao teste de push out e tipo de falha analisado por meio de lupa estereoscópica. Os dois slices restantes foram submetidos à MEV para análise da interface adesiva e superfície do material obturador. A análise de variância evidenciou haver diferença estatisticamente significante (p<0,05) entre os materiais obturadores, o protocolo de secagem do canal radicular e a interação destes fatores. AH Plus/ guta percha obteve os maiores valores médios de resistência de união (3,83 ± 0,45 MPa), sendo estatisticamente diferente (p<0,05) dos demais. O Hybrid Root SEAL/ guta percha (3,24 ± 0,46 MPa) obteve valores intermediários, sendo estatisticamente diferente dos demais (p<0,05). O cimento obturador Epiphany SE quando associado à guta percha (0,45 ± 0,10 MPa) ou ao Resilon (0,31 ± 0,09 MPa) obteve os menores valores de adesividade, sendo estatisticamente semelhantes entre si (p>0,05) e diferentes dos demais (p<0,05). O cimento AH Plus obteve os maiores valores de adesividade independente do protocolo de secagem utilizado. Na comparação entre os protocolos, o protocolo que utilizou álcool isopropílico 70% obteve maiores valores médios de adesividade. / The purpose of the present study was to evaluate the influence of the drying protocol with isopropyl alcohol on the adhesion of the sealers AH Plus, Hybrid Root Seal and Epiphany SE to intraradicular dentin. Eighty root canals of canines were subjected to biomechanical preparation and were allocated to receive one of the following drying protocols (n=40) prior to root canal filling: I- Drying with absorbent paper point and II- Drying with 70% isopropyl alcohol. Thereafter, 8 groups (n=10) were formed according to the filling material: IA and IIA AH Plus sealer; IB and IIB - Hybrid Root Seal sealer; IC and IIC- Epiphany SE sealer with gutta-percha; and ID and IID Epiphany SE sealer with Resilon. After filling, the 80 roots were sectioned transversally to obtain three 1.0-mm-thick slices from each root third. The first slice of each third was subjected to a push-out test and the failure mode was determined with a stereoscopic lens. The other two slices were prepared for SEM to examine adhesive interface and the surface of the filling materials. Analysis of variance revealed statistically significant difference (p<0.05) among the filling materials, between the root canal drying protocols as well as for the interaction of these factors. AH Plus/gutta-percha had significantly higher (p<0.05) bond strengths (3.83 ± 0.45 MPa) than the other materials. Hybrid Root SEAL/gutta-percha (3.24 ± 0.46 MPa) had intermediate values and differed significantly from the other materials (p<0.05). Epiphany SE combined with either gutta-percha (0.45 ± 0.10 MPa) or Resilon (0.31 ± 0.09 MPa) presented the lowest bond strengths without statistically significant difference (p>0.05) from each other, but with significant difference (p<0.05) from the other materials. AH Plus present the highest bond strengths regardless of the drying protocol. Comparing the two protocols, drying of root canals with 70% isopropyl alcohol was associated with the highest bond strength values to intraradicular dentin.
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Effects of Water Quality on Physico-chemical and Organoleptic Characteristics of selected Canned Fruits and Vegetables

Wilson, Anita Kay 01 May 1971 (has links)
The effect of processing water quality, specifically calcium and magnesium salt content (0-500 mg/1) and the addition of chelating agents (0- 250 mg/ 1 of aminopolycarboxylic acids, polyphosphates, hydroxycarboxylic acids or phytates), upon physico-chemical and organoleptic characteristics of canned Jonathan and Delicious apple slices, Montmorency cherries and Blue Lake green beans was investigated. Physical determinations: shear values, turbidity of syrup or brine measured via light transmittance, Hunter color and color difference meter readings and internal can corrosion; chemical composition: pectin as calcium pectate, volatile reducing substances, total acidity, pigment determinations, nitrate-nitrogen values; and sensory measurements: texture, shape, flavor, aroma, color value and uniformity of product and color value and turbidity of product brine or syrup were ascertained. Analyses of variance, Duncan's multiple mean comparison range tests and correlation or coefficients were calculated when appropriate. Use of hard water (300 mg/1) as a processing medium for canned apple slices and sour cherries decreased color and flavor acceptability but increased firmness and shear values. Excessive hardness toughened cherry epidermis making texture undesirable. Addition of 250 mg/1 CaNa2EDTA to Delicious apple slices canned in water containing 300 mg/1 salts improved color and flavor while firmness was retained. Delicious apple slices were firmer, and higher shear, nitrate-nitrogen and aroma scores and caused less detinning than Jonathan samples in all storage groups. As corrosion increased, nitrate-nitrogen, shear, firmness, flavor, aroma, and pigment values decreased. Color acceptability, reflectance, flavor and volatile reducing substance were higher and redness lower for Jonathan apple slices than Delicious samples stored at 35 and 75 F for 1 and 3 months, respectively, but not necessarily for samples stored at 100 F for 4 months. EDTA was ineffective in maintaining or improving Jonathan apple or Montmorency cherry quality, probably due ot the acidity of these cultivars. Apple and cherry quality decreased as storage temperature and duration increased from 35, 75 to 100 F for 1, 3 and 4 or 5 months, respectively, for all samples except Delicious apple slices with CaNa2EDTA. EDTA did provide most color protection in sour cherries, and citric acid, best flavor and aroma scores, while commercial and tap water processed sour cherries showed most deterioration, but none were of acceptable commercial quality after 5 month storage at 100 F. When comparing 1 month storage at 35 F with 3 months at 75 F, analyses of variance showed significant differences for every cherry characteristic measured except texture judged subjectively. All F values for apple storage variables were significant. Blue Lake green beans canned using distilled water or with 250 mg/ 1 CaNa2EDTA had higher color and greenness values, less turbidity, generally better flavor and aroma, but lower shear, shape and firmness scores than tap or hard water or commercially processed green beans. Addition of 250 mg/1 ascorbic acid to hard water used to process green beans retained greenness, clarity of brine, flavor and aroma while reducing slough and splitting of pods, when stored 4 months at 75 F.
88

Comparative Effects of Dehydration Processes on Physico- Chemical Changes in Fruits

Lee, Chang Yong 01 May 1967 (has links)
Drying with the help of sun and wind is one of the oldest methods of food preservation known to man, but artificial drying, or dehydration, has been developed and used extensively only during the last two decades. The problem in dehydration is that the water content must be decreased sufficiently to maintain the stability of the product by retarding the rates of deteriorative biochemical, microbiological, and enzymatic reactions during subsequent storage. At the same time irreversible changes should not be brought about.
89

VALORIZATION OF PROSO MILLET AND SPENT GRAIN FOR EXTRUDED SNACK DEVELOPMENT

Woomer, Joseph 01 January 2018 (has links)
Fast-paced lifestyles result in consumers replacing traditional meals with on-the-go snack foods. In general, snacks are higher in saturated fats and simple sugars, and pose health concerns for consumers, which prompts the need for healthy nutritious alternatives to common snacks. Proso millet is a nutritious, and fast growing gluten free cereal. Spent grain (SG), the main by-product of brewing and distilling, contains high amount of protein and insoluble fibers. This study utilized proso millet and spent grain in the production of an extruded expanded snack, demonstrating their appropriateness as an ingredient in food production. The first objective of this study was to determine the effect of extrusion processing conditions (moisture, barrel temperature, screw speed) on the physical, chemical, and functional properties of proso millet based extruded snack. The second objective of this research was to determine the effect of distiller’s spent grain (DSG) addition level and particle size on physicochemical and functional properties of extruded snacks. The third objective of this research was to evaluate the effect of spent grain type and particle size on the physicochemical and functional properties of extruded snacks. Samples were produced using a co-rotating twin-screw 25:1 L/D laboratory scale extruder.
90

Impact des suies issues de biocarburants sur le filtre à particules / Impact of soot derived from biofuels on diesel particulate filter

Abboud, Johnny 25 January 2018 (has links)
Ce manuscrit constitue la synthèse d'efforts visant à évaluer l'impact des composés oxygénés contenus dans des mélanges représentatifs de Biodiesel, sur leur tendance à la production de suie d'une part, et sur les propriétés physico-chimiques et la réactivité des suies d'autre part. Pour ce faire, une production stationnaire de particules de suie par un brûleur académique générant des flammes non-prémélangées a été mise en point. Dans un premier temps, nous avons montré que la teneur ainsi que la structure des additifs oxygénés à base d'ester méthylique affectent la formation de suie dans la flamme. Ainsi, les résultats ont démontré que l'efficacité d'un carburant à réduire la tendance à la production de suie en terme d'indice YSI est de plus en plus importante lorsque le contenu et/ou la longueur de la chaîne aliphatique carbonée de l'ester méthylique augmentent dans le carburant de référence. Dans un second temps, les suies " modèles " récupérées dans la région post-flamme ont été caractérisées puis comparées entre elles ainsi qu'avec une suie Biodiesel " réelle ". Les analyses ont montré que les suies issues des " surrogates " Biodiesel contenant la teneur en ester la plus élevée et la chaîne aliphatique carbonée la plus longue présentaient la distribution de taille la plus étroite, le diamètre des agrégats le plus petit, les teneurs en oxygène et en fraction organique soluble les plus faibles et étaient moins réactives. Enfin, nous avons observé que les suies " modèles " issue du brûleur académique de SANTORO et la suie " réelle " possèdent des propriétés physico-chimiques très proches et une réactivité similaire. / The aim of this work was to evaluate the effect of oxygenated compounds concentration and structure on sooting tendencies of surrogate Diesel and Biodiesel, and to investigate the properties and the oxidative reactivity of soot obtained by their combustion using an atmospheric axi-symmetric co-flow non-premixed flame burner. Results evidenced that ester functions contained in Biodiesel surrogates reduce soot production. This decrease was more pronounced when the concentration of the oxygenated additive investigated was higher. However, it has been determined that YSI decreases when the aliphatic carbon chain of the ester additive is longer. On the other hand, physico-chemical characterizations of the generated model soot revealed that oxygen and soluble organic fraction (SOF) content decreases when the amount of methyl ester based additives increases in the reference fuel. Moreover, the behavior towards oxidation indicated that the Biodiesel-derived soot was less reactive than the Diesel-derived one. Finally, it was noticed from the results obtained from laser granulometry and TPOs that the particle size distribution and the reactivity of model soot collected from the burner are in the same range of size and of maximum oxidation temperature as soot derived from a Diesel engine functioning under specific conditions and with different type of fuel blending.

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