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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.
1

Decolourization of azo dyes in textile wastewater by microbial processes

Türgay, Orcun January 2010 (has links)
<p>Decolorization of Azo dyes in synthetic wastewater composition which is similar to real textile wastewater was carried out by microbial process. Experiments were performed in two continuous systems. Experiments were performed under anaerobic conditions in order to break the nitrogen bond of the azo group (-N=N-). A synthetic dye solution which contained 200 mg/L Reactive Black 5, 200 mg/L Procion Red MX-5B and 1 g/L yeast extract was prepared. In this study, living microorganisms were used to degrade the dyes in wastewater. Rice husks which contain bacteria and fungi were used in the reactors of continuous systems. The parameters tested on continuous system were wastewater composition, the number of reactors, the amount of yeast extract in wastewater composition, the wastewater flowrate, washing the system with wood chips solution, addition of yeast extract solution.  Results have shown that increasing the number of reactors, the retention time, the amount of yeast extract and washing the system with wood chips solution had positive effects for degradation of the dyes from wastewater. When the flowrate was increased the retention time has decreased so degradation of dyes has decreased but although the flowrate increased twice, % degradation hasn’t decreased as the same ratio. Therefore this result showed that this process can be worked for faster flowrates. Microbial process is a promising technology which might be used to treat wastewater containing azo dyes with good performance.</p><p> </p>
2

Decolourization of azo dyes in textile wastewater by microbial processes

Türgay, Orcun January 2010 (has links)
Decolorization of Azo dyes in synthetic wastewater composition which is similar to real textile wastewater was carried out by microbial process. Experiments were performed in two continuous systems. Experiments were performed under anaerobic conditions in order to break the nitrogen bond of the azo group (-N=N-). A synthetic dye solution which contained 200 mg/L Reactive Black 5, 200 mg/L Procion Red MX-5B and 1 g/L yeast extract was prepared. In this study, living microorganisms were used to degrade the dyes in wastewater. Rice husks which contain bacteria and fungi were used in the reactors of continuous systems. The parameters tested on continuous system were wastewater composition, the number of reactors, the amount of yeast extract in wastewater composition, the wastewater flowrate, washing the system with wood chips solution, addition of yeast extract solution.  Results have shown that increasing the number of reactors, the retention time, the amount of yeast extract and washing the system with wood chips solution had positive effects for degradation of the dyes from wastewater. When the flowrate was increased the retention time has decreased so degradation of dyes has decreased but although the flowrate increased twice, % degradation hasn’t decreased as the same ratio. Therefore this result showed that this process can be worked for faster flowrates. Microbial process is a promising technology which might be used to treat wastewater containing azo dyes with good performance.
3

Painéis de partículas homogêneas cimento-bagaço de cana-de-açúcar curados por carbonatação acelerada / Particle-panels homogeneous cement bonded-bagasse cured by accelerated carbonation.

Cabral, Matheus Roberto 08 April 2016 (has links)
O presente estudo teve como objetivo produzir e avaliar o desempenho de painéis de partículas homogêneas de cimento-bagaço de cana-de-açúcar curados por carbonatação acelerada. Para atingir os resultados foram realizados ensaios de caracterizações morfológica e físico-química das partículas de bagaço de cana-de-açúcar, bem como ensaio de termometria para identificar a compatibilidade da matéria prima (bagaço) com o cimento. Os painéis de partículas cimento-bagaço produzidos foram submetidos a dois processos de cura distintos: 1- cura por 48 h em câmara climática, seguida por 24 h em ambiente com concentração de 15% &plusmn;0.6 de CO2, seguida por 24 dias em ambiente saturado ao ar; 2- cura em câmara climática por 48 h, seguida por 25 dias em ambiente saturado ao ar. Ao final dos 28 dias de cura e após ensaio de envelhecimento acelerado de imersão e secagem foram realizadas as caracterizações físico-mecânicas seguindo as recomendações das normativas DIN: 310; 322 e 323, bem como caracterização microestrutural e de condutividade térmica do painel de partículas cimento-bagaço. Os resultados obtidos indicaram que os painéis de partículas cimento-bagaço curados por carbonatação acelerada apresentaram melhor desempenho físico-mecânico quando comparados aos painéis não carbonatados, pois a carbonatação melhorou a interface entre as partículas e a matriz cimentícia, proporcionando maior adesividade entre as fases. E, além disso, reduziu o pH do meio alcalino em que as partículas de bagaço de cana-de-açúcar estão inseridas, minimizando o processo de degradação da lignina, celulose e hemicelulose. / The present study aimed to produce and evaluate the performance of homogeneous particles of cement panels-bagasse-sugar cured by accelerated carbonation. To achieve the results tests were carried out morphological and physical-chemical characterization of particles of bagasse of sugar cane, as well as Thermal-test to identify the compatibility of the raw material (bagasse) with cement. The particle cement-bagasse produced were subjected to two different curing processes: 1-cure for 48 h in climate Chamber, followed by 24 h in environment with concentration of 15% &plusmn; 0.6, followed by 24 days in saturated air environment; 2-cure in climate Chamber for 48 h, followed by 25 days in saturated air environment. At the end of the 28 days of curing and after accelerated aging test of soaking and drying were realized the physical-mechanical characterizations according the recommendations of the DIN standards: 310; 322 and 323, as well as micro-structural characterization and thermal conductivity of Particleboard bagasse-cement. The results obtained indicated that the particle bagasse-cement cured by accelerated carbonation presented physical-mechanical performance better than compared with non-carbonated panels because the carbonation has improved the interface between the particles and the cementitious matrix, providing greater adhesion between phases. In addition, reduced the pH of the alkaline medium in which the particles of bagasse of sugar cane are inserted, minimizing the process of degradation of lignin, cellulose and hemicellulose.
4

Painéis de partículas homogêneas cimento-bagaço de cana-de-açúcar curados por carbonatação acelerada / Particle-panels homogeneous cement bonded-bagasse cured by accelerated carbonation.

Matheus Roberto Cabral 08 April 2016 (has links)
O presente estudo teve como objetivo produzir e avaliar o desempenho de painéis de partículas homogêneas de cimento-bagaço de cana-de-açúcar curados por carbonatação acelerada. Para atingir os resultados foram realizados ensaios de caracterizações morfológica e físico-química das partículas de bagaço de cana-de-açúcar, bem como ensaio de termometria para identificar a compatibilidade da matéria prima (bagaço) com o cimento. Os painéis de partículas cimento-bagaço produzidos foram submetidos a dois processos de cura distintos: 1- cura por 48 h em câmara climática, seguida por 24 h em ambiente com concentração de 15% &plusmn;0.6 de CO2, seguida por 24 dias em ambiente saturado ao ar; 2- cura em câmara climática por 48 h, seguida por 25 dias em ambiente saturado ao ar. Ao final dos 28 dias de cura e após ensaio de envelhecimento acelerado de imersão e secagem foram realizadas as caracterizações físico-mecânicas seguindo as recomendações das normativas DIN: 310; 322 e 323, bem como caracterização microestrutural e de condutividade térmica do painel de partículas cimento-bagaço. Os resultados obtidos indicaram que os painéis de partículas cimento-bagaço curados por carbonatação acelerada apresentaram melhor desempenho físico-mecânico quando comparados aos painéis não carbonatados, pois a carbonatação melhorou a interface entre as partículas e a matriz cimentícia, proporcionando maior adesividade entre as fases. E, além disso, reduziu o pH do meio alcalino em que as partículas de bagaço de cana-de-açúcar estão inseridas, minimizando o processo de degradação da lignina, celulose e hemicelulose. / The present study aimed to produce and evaluate the performance of homogeneous particles of cement panels-bagasse-sugar cured by accelerated carbonation. To achieve the results tests were carried out morphological and physical-chemical characterization of particles of bagasse of sugar cane, as well as Thermal-test to identify the compatibility of the raw material (bagasse) with cement. The particle cement-bagasse produced were subjected to two different curing processes: 1-cure for 48 h in climate Chamber, followed by 24 h in environment with concentration of 15% &plusmn; 0.6, followed by 24 days in saturated air environment; 2-cure in climate Chamber for 48 h, followed by 25 days in saturated air environment. At the end of the 28 days of curing and after accelerated aging test of soaking and drying were realized the physical-mechanical characterizations according the recommendations of the DIN standards: 310; 322 and 323, as well as micro-structural characterization and thermal conductivity of Particleboard bagasse-cement. The results obtained indicated that the particle bagasse-cement cured by accelerated carbonation presented physical-mechanical performance better than compared with non-carbonated panels because the carbonation has improved the interface between the particles and the cementitious matrix, providing greater adhesion between phases. In addition, reduced the pH of the alkaline medium in which the particles of bagasse of sugar cane are inserted, minimizing the process of degradation of lignin, cellulose and hemicellulose.
5

Different approaches to enhance the biogas production from the anaerobic digestion of lignocellulosic materials / Différentes approches pour améliorer la production de biogaz à partir de biomasse lignocellulosique

Mancini, Gabriele 15 December 2017 (has links)
La production de biogaz par digestion anaérobie (DA) est une technologie renouvelable de longue date et un bioprocessus en croissance continue. Les matériaux lignocellulosiques (ML) présentent plusieurs caractéristiques qui les rendent particulièrement attrayants parmi les substrats couramment employés dans les bioréacteurs anaérobies. En particulier, les ML sous la forme de résidus agricoles ont été reconnus comme la matière première la plus appropriée pour la production de biométhane en raison de leur haute disponibilité, de leur faible coût, de leur durabilité et de leur absence de concurrence directe avec la production alimentaire. Cependant, leur récurrence à la conversion biologique entrave leur application pour la production à grande échelle de biogaz et nécessite une étape de prétraitement pour améliorer la dégradabilité microbienne. En plus des défis posés par la structure lignocellulosique, la fourniture de oligo-éléments (OE) a souvent été jugée insuffisante dans les digesteurs de biogaz. La croissance microbienne dépend de la disponibilité et de la quantité optimale de plusieurs OE spécifiques, constituants essentiels des cofacteurs dans les systèmes enzymatiques impliqués dans la biochimie de la formation de méthane. Différents prétraitements chimiques, à savoir le N-méthylmorpholine-N-oxyde (NMMO), le procédé organosolv et un prétraitement alcalin à l'aide de NaOH ont été étudiés pendant plusieurs expériences en lots pour améliorer les rendements de production de biogaz différents peau, coquille de fève de cacao et paille de blé). Les changements dans la cristallinité de la cellulose, la valeur de rétention d'eau et la composition chimique ont été évalués pour mieux évaluer l'effet des différents prétraitements étudiés sur la structure lignocellulosique. En outre, l'addition de différentes doses de Fe, Co, Ni et Se sur la DA de paille de riz a été étudiée, évaluant l'influence de l'origine de l'inoculum, ainsi que la performance et l'effet synergique de la combinaison d'un prétraitement alcalin avec addition de trace éléments avant la DA de paille de riz. La biodisponibilité des OE lors des tests de potentiel de biométhane par lots a également été évaluée en appliquant une technique d'extraction séquentielle. Les trois prétraitements étudiés étaient des méthodes efficaces pour améliorer la production de biométhane à partir des LM utilisées. Le rendement en biométhane de la DA de paille de riz a augmenté de 82 et 41% respectivement après le NMMO et le prétraitement organosolv. Comparé à la même expérience, le prétraitement NMMO, organosolv et NaOH a permis d'améliorer la DA de la paille de blé, ce qui affecte différemment la composition chimique de la LM brute. Le rendement cumulatif de production de biométhane de 274 mL de CH4/g VS obtenu avec la paille de blé non traitée a été augmenté de 11% par le prétraitement du NMMO et de 15% par le prétraitement organosolv et alcalin. Les coquilles de noisettes et de fèves de cacao, qui n'avaient jamais été étudiées auparavant comme substrats AD, présentaient un bon potentiel de production de biogaz, avec des rendements cumulatifs de biométhane respectivement de 223-261 et 199-231 mL CH4/g VS pour les charges non traitées. Cependant, les prétraitements à la fois de NMMO et d'organosolv n'ont pas conduit à une amélioration significative des rendements de production de biométhane de ces deux LM. La supplémentation des OE n'a eu qu'un effet mineur par rapport aux méthodes de prétraitement. L'ajout de Fe, Co, Ni et Se n'a pas entraîné d'amélioration significative de la DA de paille de riz, alors que l'utilisation du prétraitement de NaOH au cours de la même expérimentation a provoqué une augmentation considérable de la DA, augmentant la production de biogaz de 21%. L'effet négligeable observé après la supplémentation des OE sur la paille de riz pourrait être lié à sa structure lignocellulosique complexe qui nécessite une amélioration de l'hydrolyse qui est l'étape limitante / Biogas production via anaerobic digestion (AD) is a long-standing renewable technology and a continuously growing bioprocess worldwide. Lignocellulosic materials (LMs) present several features that make them especially attractive among the organic substrates commonly employed in anaerobic bioreactors. In particular, LMs under the form of agricultural residues have been acknowledged as the most suitable feedstock for biomethane production due to their high availability, low cost, sustainability and no direct competition with food and feed production. However, their recalcitrance to biological conversion hinders their application for full-scale production of biogas and requires a pretreatment step to improve the LM microbial degradability. In addition to the challenges posed by the lignocellulosic structure, the supply of trace elements (TEs) has often been found insufficient within biogas digesters. The microbial growth depends on the availability and optimal amount of several specific TEs, which are essential constituents of cofactors in enzyme systems involved in the biochemistry of methane formation. Different chemical pretreatments, namely the solvent N-methylmorpholine-N-oxide (NMMO), the organosolv process, and an alkaline pretreatment using NaOH, were investigated during several batch experiments to enhance the biogas production yields from different LMs (i.e. rice straw, hazelnut skin, cocoa bean shell and wheat straw). Changes in the cellulose crystallinity, water retention value and chemical composition were assessed to better evaluate the effect of the different pretreatments studied on the lignocellulosic structure. Furthermore, the addition of different doses of Fe, Co, Ni and Se on the AD of rice straw was studied, evaluating the influence of the inoculum origin, as well as the performance and synergistic effect of combining an alkaline pretreatment with the addition of trace elements prior to the AD of rice straw. The bioavailability of TEs during batch biomethane potential tests was also evaluated applying a sequential extraction technique. The three pretreatments investigated were effective methods for enhancing the biomethane production from the employed LMs. The biomethane yield from the AD of rice straw increased by 82 and 41% after the NMMO and organosolv pretreatment, respectively. When compared within the same experiment, the NMMO, organosolv and NaOH pretreatment were able to improve the AD of wheat straw, differently affecting the chemical composition of the raw LM. The cumulative biomethane production yield of 274 mL CH4/g VS obtained with the untreated wheat straw was enhanced by 11% by the NMMO pretreatment and by 15% by both the organosolv and alkaline pretreatment. Hazelnut skin and cocoa bean shell, which were never investigated before as AD substrates, showed a good potential for biogas production, with cumulative biomethane yields of 223-261 and 199-231 mL CH4/g VS, respectively, for the untreated feedstocks. However, both NMMO and organosolv pretreatments did not lead to a significant enhancement of the biomethane production yields from these two LMs. The TE supplementation had only a minor effect compared to the pretreatment methods. The addition of Fe, Co, Ni and Se did not result in a significant improvement of the AD of rice straw, whereas the use of the NaOH pretreatment, during the same batch experiment, caused a considerable enhancement of the AD, increasing the biogas production yield by 21%. The negligible effect observed after TE supplementation on the AD of rice straw could be linked to its complex lignocellulosic structure, which requires an enhancement of the hydrolysis, which, rather than the methanogenesis, is the rate-limiting step
6

Aproveitamento de resíduos agroindustriais para elaboração de filmes biodegradáveis / Reuse of agroindustrial residue for biodegradable films elaboration

Maniglia, Bianca Chieregato 22 March 2017 (has links)
Este trabalho teve como objetivo principal o aproveitamento dos resíduos agroindustriais provenientes da extração do pigmento de cúrcuma e do óleo de babaçu para elaboração de filmes biodegradáveis. Foram utilizados três diferentes métodos (moagem em meio ácido AS, em meio alcalino KS e em água WS) para isolamento do amido de babaçu e de cúrcuma. Os resíduos e amidos foram caracterizados em composição química, cor, distribuição do tamanho de partícula, difração de raios-X, microscopia eletrônica de varredura, poder de inchamento e solubilidade, espectroscopia de infravermelho, propriedades térmicas, teor de compostos fenólicos e atividade antioxidante. Os métodos AS e KS forneceram materiais com maior grau de pureza, porém menor teor de amilose. Filmes foram elaborados a partir dos amidos de cúrcuma e de babaçu, e também do mesocarpo de babaçu e tiveram suas propriedades mecânicas, funcionais e ativa determinadas. Filmes elaborados com os amidos de babaçu são mais resistentes e rígidos, menos elongáveis, solúveis e permeáveis ao vapor de água que com mesocarpo de babaçu. Filmes de amido de babaçu WS foram mais resistentes e rígidos, menos flexíveis, mais cristalinos, menos solúveis em água e hidrofílicos, com menor capacidade de absorção de água. Filmes de amido de babaçu AS apresentaram maior atividade antioxidante. O efeito de diferentes plastificantes (glicerol, sorbitol, ureia e glicose) nas propriedades dos filmes de amidos de babaçu também foi estudado. Notou-se que as propriedades finais dos filmes dependeu da interação entre os componentes na matriz: plastificante, amido e água. Para o babaçu também se realizou um estudo sobre os efeitos da concentração de sorbitol (Cs) e da temperatura de aquecimento (Ta) nas propriedades dos filmes através de um planejamento experimental 22 utilizando a metodologia de superfície de resposta e análise de multiresposta para avaliação dos resultados. As regiões sugeridas para se obter filmes com melhores propriedades foram: 26 a 30 g de sorbitol/100 g de amido acompanhado de temperatura de aquecimento de 78 a 80 °C. Para a cúrcuma, apesar do processo de isolamento do amido obter altos teores deste carboidrato (~80%), o material se apresenta bem compactado devido ao processamento industrial com presença de aquecimento. Assim, filmes elaborados com amidos de cúrcuma exigiram 4 h de aquecimento para o seu processamento. Filmes de amido de cúrcuma WS apresentaram maior flexibilidade, menor xxv resistência e rigidez, maior solubilidade e molhabilidade e os filmes de amido de cúrcuma AS, maior atividade antioxidante. Foram elaboradas também blendas com os diferentes amidos de cúrcuma com fécula de mandioca em diferentes proporções (30:70, 50:50 e 70:30). As blendas possibilitaram a elaboração de materiais com menor tempo de preparo (1 h). A adição de fécula de mandioca nas blendas diminuiu a resistência mecânica e rigidez, mas aumentou a elongação, solubilidade e permeabilidade ao vapor de água enquanto que a adição de amido de cúrcuma proporcionou aumento da atividade antioxidante nestes materiais. Também fora realizado tratamentos (mecânicos/químicos) do resíduo de cúrcuma com o objetivo de tornar este material com melhor capacidade filmogênica. Estes tratamentos permitiram melhor incorporação do material lignocelulósico à matriz do filme e liberação do amido, além de ter promovido oxidação do amido causando a formação de novos grupamentos (carboxílicos e carbonílicos), o que permitiu obter filmes com melhores propriedades que os elaborados com amido de cúrcuma / The main objective of this work was the use of agroindustrial residues from the extraction of turmeric pigment and babassu oil for the preparation of biodegradable films. Three different methods (steeping in acid media - AS, in alkaline media - KS and in water - WS) were used to isolate babassu and turmeric starch. The residues and starches were characterized in centesimal composition, color, particle size distribution, X-ray diffraction, scanning electron microscopy, swelling power and solubility, infra-red spectroscopy, thermal properties, phenolic compounds content and antioxidant activity. The AS and KS methods provided materials with higher purity but less amylose content. Films were made from the turmeric and babassu starches, and also from the babassu mesocarp and had it mechanical, functional and active properties determined. Films made from babassu starches are more resistant and rigid, less flexible, soluble and permeable to water vapor than with babassu mesocarp. WS babassu starch films were more resistant and rigid, less flexible, more crystalline, less water soluble and hydrophilic, with less water absorption capacity. AS babassu starch films showed the highest antioxidant activity. The effect of different plasticizers (glycerol, sorbitol, urea and glucose) on the properties of babassu starch films was also studied. It was noted that the final properties of the films depended on the interaction between the components in the matrix: plasticizer, starch and water. A study on the effects of sorbitol concentration (Cs) and heating temperature (Ta) on the properties of the films was also carried out for the babassu through an experimental design 22 using the response surface methodology and multi-response analysis for evaluation of the results. The regions suggested to obtain films with better properties were: 26 to 30 g of sorbitol / 100 g of starch accompanied by a heating temperature of 78 to 80 °C. For turmeric, although the starch isolation process obtained high levels of this carbohydrate (~ 80%), the material presents well compacted due to industrial processing with presence of heating. Thus, films made with turmeric starches required 4 h of heating for processing. Turmeric WS starch films showed greater flexibility, lower strength and stiffness, higher solubility and wettability and the films of turmeric starch AS, higher antioxidant activity. Blends with the different turmeric starches with cassava starch in different proportions (30:70, 50:50 and 70:30) were also prepared. The blends made possible the preparation of materials with less preparation time (1 h). The addition of cassava starch to the blends decreased xxvii mechanical rigid and mechanical resistance, but increased elongation, solubility and water vapor permeability while the addition of turmeric starch provided increased antioxidant activity in these materials. It was done also treatments (mechanical / chemical) in the turmeric residue to have this material with better filmogenic capacity. These treatments allowed better incorporation of the lignocellulosic material to the matrix of the film and release of the starch, besides promoting oxidation of the starch causing the formation of new groups (carboxylic and carbonylic), which allowed to obtain films with better properties than those elaborated with starch of turmeric
7

Estudo de biofilmes funcionais como revestimento em painéis multicamada para uso em instalação agroindustrial / Study of functional biofilms as coating in multilayer panels for use in agroindustrial facilities

Nakanishi, Erika Yukari 15 January 2018 (has links)
Este projeto tem como objetivo o estudo do recobrimento superficial de filmes poliméricos à base de látex e breu, com microbicida de prata em painéis multicamadas de bagaço de cana-de-açúcar, reforçados com partículas de bambu (PMBB), visando seu o uso como material isolante térmico em instalação agroindustrial sujeita a ambientes úmidos e com grande carga bacteriana. O projeto foi desenvolvido em quatro etapas. Na etapa 1 (Estudo dos painéis multicamadas), foi realizado o estudo de dois diferentes procedimentos de moldagem, sendo moldagem 1 (PMBB-M1) com prensagem nas camadas e a moldagem 2 (PMBB-M2) sem prensagens nas camadas. Na avaliação física e mecânica o painel PMBB-M2 apresentou melhor desempenho físico e mecânico, por conta da melhor interação entre as camadas, quando comparado ao painel PMBB-M1. A etapa 2 (Estudo do tratamento superficial dos painéis) consistiu na produção e caracterização dos filmes de breu, látex-LT e látex-LS, e na avaliação do recobrimento do painel PMBB e da sua durabilidade expostos às intempéries ambientais (sol, chuva, vento e orvalho). Os filmes apresentaram bom desempenho físico, dificultando a penetração de água no material, contudo, a exposição à radiação e as intempéries climáticas promoveram a degradação dos filmes, apesar disso o látex-LT e o breu apresentaram, até os três meses de envelhecimento natural, melhor desempenho mecânico. A etapa 3 (Estudo da impregnação de nanopartículas de prata (AgNPs) nos filmes) consistiu na preparação e avaliação dos filmes com AgNPs. Por meio da análise microbiológica constatou-se que os filmes de látex-LT e breu apresentaram caráter bacteriostático. Por fim, na etapa 4 (Aplicação dos painéis PMBB em Instalação Suinícola), foi analisado o potencial do painel PMBB-M2 como material isolante térmico, na forma de abrigo para leitão (escamoteador) em uma granja de suínos. Nessa etapa, foi avaliado o microclima gerado no interior dos escamoteadores aquecidos com lâmpada incandescente, por meio da coleta de dados ambientais e análise dos índices de conforte térmico. O painel apresentou bom desempenho, atendendo a faixa de temperatura e umidade de conforto térmico para os leitões na primeira semana de vida. Portanto, pode-se concluir que os filmes de breu e látex-LT no painel PMBB-M2, promoveram uma impermeabilização do material e por apresentarem caráter bacteriostático, evitaram a proliferação de bactérias quando em contato com os filmes, sendo assim, a aplicação deste material como isolante térmico em instalação para suíno apresenta um grande potencial, pois, o recobrimento no material propicia sua aplicação em um ambiente úmido e com grande carga bacteriana. / This project aims the study of surface coatings with polymeric films based on latex and rosin, by using a microbicide agent of\' silver in multilayer panels of sugarcane bagasse reinforced with bamboo particles (PMBB) to be used as an insulate material in agroindustrial facilities subject to humid environments with high bacterial load. This project was conducted into four steps. In the step 1 (Study of the multilayer panels), the evaluation of two different molding procedures was conducted, with molding 1 (PMBB-M1) with pre-pressing in the layers and molding 2 (PMBB-M2) without pre-pressing in the layers. Physical and mechanical properties of the PMBB-M2 panel presented better physical and mechanical performance due to the best interaction between the layers compared to the PMBB-M1 panel. In the step 2 (Study of the superficial treatment of panels), it was studied the production and characterization of the films of rosin, latex-LT and latex-LS, as well as the evaluation of the PMBB panel covering, and evaluation of the durability of these panels exposed to weather conditions (sun, rain, wind and dew). The films presented good physical performance, making it difficult to penetrate water in the material, on the other hand, by exposing the materials to radiation and weather conduction it was noticed the degradation of the films, despite the fact that latex-LT and rosin presented better mechanical performance until three months of age. In the step 3 (Study of impregnation of silver nanoparticles (AgNPs) in the films) it was conducted the preparation and evaluation of the films with AgNPs. By means of the microbiology analyses it was stated that the latex-LT and rosin presented bacteriostatic character. In the step 4 (Application of PMBB panels in Poultry facilities) it was evaluated the potential of the PMBB panel as an insulation material in a pig-farm as a piglet shelter. In this step, the microclimate generated inside of the pig shelter heated by incandescent lamps was evaluated through the collection of environmental data and evaluation of the thermal comfort indices. The panel presented good performance, taking into account the temperature and humidity range of thermal comfort for the piglets in the first week of life. Therefore, it can be concluded that the films of rosin and latex-LT in the PMBB panel, promoted a waterproofing of the materials and due to the bacteriostatic character, it was noticed that proliferation of the bacteria when in contact with the films was avoided, thus, the application of this material as thermal insulation in pig installation presents a great potential, due to the coating in the material and propitiates its application in a humid environment and with bacterial load.
8

Avaliação de condições fermentativas iniciais de Spathaspora arborariae UFMG-HM19.1 na produção de etanol a partir do hidrolisado de bagaço de cana-de-açúcar / Evaluation of inital fermentative conditions on Spathaspora arborariae UFMG-HM19.1 in ethanol production using hydrolysate of sugarcane bagasse

Guilherme Silveira Simões 07 October 2011 (has links)
O presente trabalho teve como objetivo contribuir para o desenvolvimento de uma tecnologia de obtenção de etanol por via biotecnológica, verificando o comportamento da levedura Spathaspora arborariae UFMG-HM19.1 na fermentação de xilose em hidrolisado hemicelulósico de bagaço de cana-deaçúcar para etanol. Foram elaborados três planejamentos fatoriais 2³ completos com objetivo de determinar condições favoráveis de suplementação nutricional e fermentação do hidrolisado hemicelulósico de bagaço de cana-de-açúcar. O primeiro experimento teve o intuito de a avaliar o efeito da aeração durante a fermentação de etanol, sendo que as melhores condições para aeração foram a agitação em 200 rpm, volume de hidrolisado 25 ml em frascos de 125 ml. Após obtenção desses dados, foram utilizados sulfato de amônio, sulfato de magnésio e extrato de levedura como fatores em um segundo delineamento experimental, onde obteve-se como melhor combinação a utilização de extrato de levedura na concentração de 1g.l-1. Finalmente, realizou-se o ultimo planejamento experimental, utilizando os dados experimentais anteriores, utilizando como fatores o pH, a temperatura e a concentração inicial de inóculo, chegando ao resultados das condições ideais de pH (pH=4), temperatura (40°) e concentração inicial de inóculo (0,5g.l-1). Apesar das condições indicadas e do satisfatório fator de rendimento de etanol (Yp/s= 0,50), a levedura cultivada nessas condições mostrou-se com uma baixa produtividade (Qp=0,15), assim como suas vantagens, tais como a fermentação em temperatura elevada e baixo pH, assim como um fator de rendimento adequado e uma razoável assimilação de açúcares. / The aim of this study is to contribute to the technological development of ethanol production by biotechnological pathways, studying the behavior of the yeast Spathaspora arborariae UFMG-HM19 in the fermentation of xylose in hemicellulosic hydrolyzate of sugarcane bagasse for ethanol. Three experimental designs were made to determine the satisfatory set of factors to produce ethanol from the lignocellulosic material. The first experiment was designed to evaluate the effect of aeration during fermentation to ethanol, that would be better under this conditions: agitation at 200 rpm, 25 ml volume of hydrolyzed in 125 ml bottles. After obtaining these data, we used ammonium sulphate, magnesium sulphate and yeast extract as factors in a second experiment, which was obtained as the best combination to use yeast extract in a concentration of 1 g.l-1. Finally, there was the last experimental design, using previous experimental data, using factors such as pH, temperature and initial concentration of inoculum, even to the results of the ideal conditions of pH (pH = 4), temperature (40 °C) and initial concentration of inoculums (0,5 g.L-1). Despite the good conditions indicated and ethanol yield factor (Yp/s =0,50), the yeast grown under these conditions was shown with a low productivity (Qp=0,14 g.l-1h-1) as well as its advantages, such as fermentation at high temperature and low pH, as well as a adequate efficiency and a reasonable sugar assimilation.
9

Deleção parcial do fator de transcrição ACE1 para otimização da produção de celulases por trichoderma reesei RUT-C30 / partial deletion of ACE1 transcription factor for optimization Trichoderma reesei RUT-C30 cellulase production

Dudek, Débora Nakadomari 07 February 2017 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2017-08-29T17:53:24Z No. of bitstreams: 2 Dissertação DEBORA.pdf: 1099973 bytes, checksum: aabc08a0f4d095fb9706cae57d8da79a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-29T17:53:24Z (GMT). No. of bitstreams: 2 Dissertação DEBORA.pdf: 1099973 bytes, checksum: aabc08a0f4d095fb9706cae57d8da79a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Second generation bioethanol employs lignocellulosic materials in its preparation. One of the steps for these materials degradation utilizes cellulases produced by microorganisms. Among these, Trichoderma reesei fungus is one of the main cellulases producers used in industry. This fungus genetic modification can lead to enzimes production optimization, reducing cost and improving biofuels manufacture. Thus, the present work objective was delete the sequence encoding zinc fingers motifs of cellulase ACE1repressor transcription factor from T. reesei RUT-C30 fungus, seeking enzymatic production optimization. In primers construction for amplification ACE1 regions 5’ and 3' and the hph selection marker, which confers hygromycin B resistance, Joint Genome Institute - JGI site and the BioEdit ® program were used. The deletion cassette with pRS426 vector construction was mediated by Saccharomyces cerevisiae SC9721 yeast. After the cassette construction, T. reesei RUT-C30 transformation was made by protoplast and this transformation confirmation was effected by part of the hph using hphNestF and hphNestR amplification primers. After transformation with mutants obtained, endoglucanase, exoglucanase and total cellulase activity was quantified with carboxymethylcellulose substrates (CMC), microcrystalline cellulose (Avicel®) and Whatman paper filter (PF), respectively. The enzymatic production and biomass hydrolysis efficiency were performed comparing RUT-C30 strain for mutants. After deletion cassette construction, a 3501 bp fragment amplification confirmed the cassette formation. Posteriorly, RUT-C30 strain transformation, a 989 bp amplification was observed, confirming the 3 mutants target sequence deletion. With cellulase activity assay, 3 transformed strain showed higher enzymatic production when compared to RUT-C30 strain. In this comparison, a significant statistical difference was observed of RUT-C30Δace1-1 strain with Avicel® and PF (p <0.001) CMC (p <0.01), RUT-C30Δace1-2 strain with CMC (p<0,01) e PF (p<0,05), and RUT-C30Δace1-3 strain with Avicel (p<0,001), CMC and PF (p<0,01). The mutants also showed greater efficiency in biomass hydrolysis, with release sugar increase between 21 and 42%. Based on this study, mutants are promising for most efficient and viable ethanol production. Nevertheless, additional tests must be carried out to better understand these fungi applicability in the industrial level. / O bioetanol de segunda geração emprega materiais lignocelulósicos na sua elaboração. Uma das etapas para a degradação destes materiais utiliza celulases produzidas por microrganismos. Dentre estes, o fungo Trichoderma reesei é um dos principais produtores de celulases utilizadas na indústria. A modificação genética deste fungo pode levar à otimização da produção de suas enzimas, diminuindo o custo e melhorando a fabricação de biocombustíveis. Desta forma, o objetivo do trabalho foi deletar a região dos motivos dedos de zinco no gene que codifica o fator de transcrição repressor de celulase ACE1 do fungo T. reesei RUT-C30, buscando a otimização na produção enzimática. Na construção dos primers para amplificação das regiões 5’ e 3’ de ace1 e do marcador de seleção hph, que confere resistência à higromicina B, utilizou-se o site Joint Genome Institute – JGI e o programa BioEdit®. A construção do cassete de deleção com o vetor pRS426 foi mediado pela levedura Saccharomyces cerevisiae SC9721. Posteriormente, a construção do cassete, a transformação de T. reesei RUT-C30 foi realizada através de protoplasto e a confirmação desta transformação foi efetuada por amplificação de parte do hph utilizando os primers hphNestF e hphNestR. Após a transformação, com os mutantes obtidos, a atividade de endoglucanase, exoglucanase e celulase total foi quantificada com os substratos carboximetilcelulose (CMC), celulose microcristalina (Avicel®) e papel de filtro Whatman (PF), respectivamente. A produção enzimática e a eficiência na hidrólise da biomassa foram realizadas comparando-se a linhagem RUT-C30 aos mutantes. Após a construção do cassete de deleção, a amplificação de um fragmento de 3501 pb confirmou a formação do cassete. E, posteriormente à transformação da linhagem RUT-C30, o amplificado de 989 pb foi observado, confirmando a deleção da sequência alvo em 3 mutantes. Com o ensaio de atividade de celulases, as 3 linhagens transformadas mostraram maior produção enzimática quando comparadas à linhagem RUT-C30. Nessa comparação, foi observada diferença estatística significativa da linhagem RUT-C30Δace1-1 com Avicel® e PF (p<0,001), da linhagem RUTC30Δace1- 2 com CMC (p<0,01) e PF (p<0,05) e da linhagem RUT-C30Δace1-3 com Avicel (p<0,001), CMC e PF (p<0,01). Os mutantes também apresentaram maior eficiência na hidrólise da biomassa, com aumento na liberação de açúcar entre 21 e 42%. Com base nos dados deste estudo, os mutantes apresentam-se promissores para a produção mais eficiente e viável de etanol. Apesar disso, testes adicionais devem ser realizados para melhor entendimento da aplicabilidade destes fungos a nível industrial.
10

Avaliação de condições fermentativas iniciais de Spathaspora arborariae UFMG-HM19.1 na produção de etanol a partir do hidrolisado de bagaço de cana-de-açúcar / Evaluation of inital fermentative conditions on Spathaspora arborariae UFMG-HM19.1 in ethanol production using hydrolysate of sugarcane bagasse

Simões, Guilherme Silveira 07 October 2011 (has links)
O presente trabalho teve como objetivo contribuir para o desenvolvimento de uma tecnologia de obtenção de etanol por via biotecnológica, verificando o comportamento da levedura Spathaspora arborariae UFMG-HM19.1 na fermentação de xilose em hidrolisado hemicelulósico de bagaço de cana-deaçúcar para etanol. Foram elaborados três planejamentos fatoriais 2³ completos com objetivo de determinar condições favoráveis de suplementação nutricional e fermentação do hidrolisado hemicelulósico de bagaço de cana-de-açúcar. O primeiro experimento teve o intuito de a avaliar o efeito da aeração durante a fermentação de etanol, sendo que as melhores condições para aeração foram a agitação em 200 rpm, volume de hidrolisado 25 ml em frascos de 125 ml. Após obtenção desses dados, foram utilizados sulfato de amônio, sulfato de magnésio e extrato de levedura como fatores em um segundo delineamento experimental, onde obteve-se como melhor combinação a utilização de extrato de levedura na concentração de 1g.l-1. Finalmente, realizou-se o ultimo planejamento experimental, utilizando os dados experimentais anteriores, utilizando como fatores o pH, a temperatura e a concentração inicial de inóculo, chegando ao resultados das condições ideais de pH (pH=4), temperatura (40°) e concentração inicial de inóculo (0,5g.l-1). Apesar das condições indicadas e do satisfatório fator de rendimento de etanol (Yp/s= 0,50), a levedura cultivada nessas condições mostrou-se com uma baixa produtividade (Qp=0,15), assim como suas vantagens, tais como a fermentação em temperatura elevada e baixo pH, assim como um fator de rendimento adequado e uma razoável assimilação de açúcares. / The aim of this study is to contribute to the technological development of ethanol production by biotechnological pathways, studying the behavior of the yeast Spathaspora arborariae UFMG-HM19 in the fermentation of xylose in hemicellulosic hydrolyzate of sugarcane bagasse for ethanol. Three experimental designs were made to determine the satisfatory set of factors to produce ethanol from the lignocellulosic material. The first experiment was designed to evaluate the effect of aeration during fermentation to ethanol, that would be better under this conditions: agitation at 200 rpm, 25 ml volume of hydrolyzed in 125 ml bottles. After obtaining these data, we used ammonium sulphate, magnesium sulphate and yeast extract as factors in a second experiment, which was obtained as the best combination to use yeast extract in a concentration of 1 g.l-1. Finally, there was the last experimental design, using previous experimental data, using factors such as pH, temperature and initial concentration of inoculum, even to the results of the ideal conditions of pH (pH = 4), temperature (40 °C) and initial concentration of inoculums (0,5 g.L-1). Despite the good conditions indicated and ethanol yield factor (Yp/s =0,50), the yeast grown under these conditions was shown with a low productivity (Qp=0,14 g.l-1h-1) as well as its advantages, such as fermentation at high temperature and low pH, as well as a adequate efficiency and a reasonable sugar assimilation.

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