Made available in DSpace on 2014-12-17T15:01:20Z (GMT). No. of bitstreams: 1 WilaciEFJ.pdf: 1838358 bytes, checksum: 40ec11f34b65cc0544a9b15c91dae65a (MD5) Previous issue date: 2002-04-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The present work had as objective to apply an experimental planning aiming at to improve the efficiency of separation of a new type of mixer-settler applied to treat waste water contaminated with oil. An unity in scale of laboratory, was installed in the Post-graduation Program of Chemical Engineering of UFRN. It was constructed in partnership with Petrobras S.A. This called device Misturador-Decantador a Invers?o de Fases (MDIF) , possess features of conventional mixer-settler and spray column type. The equipment is composed of three main parts: mixing chamber; chamber of decantation and chamber of separation. The efficiency of separation is evaluated analyzing the oil concentrations in water in the feed and the output of the device. For the analysis one used the gravimetric method of oil and greases analysis (TOG). The system in study is a water of formation emulsified with oil. The used extractant is a mixture of Turpentine spirit hydro-carbons, supplied for Petrobras. It was applied, for otimization of the efficiency of separation of the equipment, an experimental planning of the composite central type, having as factorial portion fractionary factorial planning 2 5-2, with the magnifying of the type star and five replications in the central point. In this work, the following independents variables were studied: contents of oil in the feed of the device; volumetric ratio (O/A); total flowrate ; agitation in the mixing chamber and height of the organic bed. Minimum and maximum limits for the studied variables had been fixed according previous works. The analysis of variance for the equation of the empirical model, revealed statistically significant and useful results for predictions ends. The variance analysis also presented the distribution of the error as a normal distribution and was observed that as the dispersions do not depend on the levels of the factors, the independence assumption can be verified. The variation around the average is explained by 98.98%, or either, equal to the maximum value, being the smoothing of the model in relation to the experimental points of 0,98981. The results present a strong interaction between the variable oil contents in the feed and agitation in the mixing chamber, having great and positive influence in the separation efficiency. Another variable that presented a great positive influence was the height of the organic bed. The best results of separation efficiency had been obtained for high flowrates when associates the high oil concentrations and high agitation. The results of the present work had shown excellent agreement with the results carried out through previous works with the mixer-settler of phase inversion / O presente trabalho teve como objetivo otimizar a efici?ncia de separa??o de um novo aparelho do tipo misturador-decantador aplicado ao tratamento de ?guas residu?rias contaminadas com petr?leo. Foi utilizado um equipamento em escala de laborat?rio, instalado no Programa de P?s-gradua??o em Engenharia Qu?mica da UFRN, que foi constru?do em parceria com a Petrobras S.A. Este aparelho denominado Misturador-Decantador ? Invers?o de Fases (MDIF), possui caracter?sticas de um misturador-decantador convencional e de uma coluna tipo spray. O equipamento ? composto de tr?s partes principais: c?mara de mistura; c?mara de decanta??o e c?mara de separa??o. A efici?ncia de separa??o ? avaliada analisando-se as concentra??es de ?leo em ?gua na alimenta??o e na sa?da do aparelho. Para a an?lise utilizou-se o m?todo da an?lise de ?leo e graxas (TOG) por gravimetria. O sistema em estudo ? uma ?gua de forma??o emulsionada com ?leo. O extratante utilizado ? uma mistura de hidrocarbonetos denominada de Aguarr?s, fornecido pela Petrobras. Aplicou-se, para a otimiza??o da efici?ncia de separa??o do equipamento, um planejamento experimental do tipo central composto, tendo como por??o fatorial o planejamento fatorial fracion?rio 2 5-2, com a amplia??o do tipo estrela e cinco repeti??es no ponto central. Neste trabalho, estudam-se as seguintes vari?veis independentes: teor de ?leo na ?gua residu?ria de carga da coluna; rela??o volum?trica org?nico/aquoso (O/A); vaz?o efetiva total; agita??o na c?mara de mistura e altura do leito org?nico. Foram fixados limites m?nimos e m?ximos para as vari?veis estudadas de acordo com trabalhos realizados anteriormente. A an?lise de vari?ncia para a equa??o do modelo emp?rico, mostrou-se estatisticamente significante e ?til para fins preditivos. A an?lise de vari?ncia tamb?m apresentou a distribui??o do erro como uma distribui??o normal e observou-se que como as dispers?es n?o dependem dos n?veis dos fatores, a suposi??o de independ?ncia pode ser verificada. A varia??o em torno da m?dia ? explicada por 98,98%, ou seja, igual ao valor m?ximo explic?vel, sendo o ajuste do modelo em rela??o aos pontos experimentais de 0.98981. Os resultados apresentam uma intera??o muito forte entre as vari?veis teor de ?leo e agita??o na c?mara de mistura, tendo grande e positiva influ?ncia na efici?ncia de separa??o. Outra vari?vel que apresentou-se com grande e positiva influ?ncia foi a altura do leito org?nico. Os melhores resultados de efici?ncia de separa??o foram obtidos para altas vaz?es quando associadas a altas concentra??es de ?leo e alta agita??o. Os resultados obtidos no presente trabalho mostraram excelente concord?ncia com os resultados de trabalhos anteriores realizados com o misturador-decantador ? invers?o de fases

Made available in DSpace on 2014-12-17T15:01:47Z (GMT). No. of bitstreams: 1 ElisangelaLG.pdf: 1590433 bytes, checksum: 344724364926bacba0bb6a0d130edd0d (MD5) Previous issue date: 2009-05-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The aim of the present study was to extract vegetable oil from brown linseed (Linum usitatissimum L.), determine fatty acid levels, the antioxidant capacity of the extracted oil and perform a rapid economic assessment of the SFE process in the manufacture of oil. The experiments were conducted in a test bench extractor capable of operating with carbon dioxide and co-solvents, obeying 23 factorial planning with central point in triplicate, and having process yield as response variable and pressure, temperature and percentage of cosolvent as independent variables. The yield (mass of extracted oil/mass of raw material used) ranged from 2.2% to 28.8%, with the best results obtained at 250 bar and 50?C, using 5% (v/v) ethanol co-solvent. The influence of the variables on extraction kinetics and on the composition of the linseed oil obtained was investigated. The extraction kinetic curves obtained were based on different mathematical models available in the literature. The Mart?nez et al. (2003) model and the Simple Single Plate (SSP) model discussed by Gaspar et al. (2003) represented the experimental data with the lowest mean square errors (MSE). A manufacturing cost of US$17.85/kgoil was estimated for the production of linseed oil using TECANALYSIS software and the Rosa and Meireles method (2005). To establish comparisons with SFE, conventional extraction tests were conducted with a Soxhlet device using petroleum ether. These tests obtained mean yields of 35.2% for an extraction time of 5h. All the oil samples were sterilized and characterized in terms of their composition in fatty acids (FA) using gas chromatography. The main fatty acids detected were: palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2n-6) and α-linolenic (C18:3n-3). The FA contents obtained with Soxhlet dif ered from those obtained with SFE, with higher percentages of saturated and monounsaturated FA with the Soxhlet technique using petroleum ether. With respect to α-linolenic content (main component of linseed oil) in the samples, SFE performed better than Soxhlet extraction, obtaining percentages between 51.18% and 52.71%, whereas with Soxhlet extraction it was 47.84%. The antioxidant activity of the oil was assessed in the β-carotene/linoleic acid system. The percentages of inhibition of the oxidative process reached 22.11% for the SFE oil, but only 6.09% for commercial oil (cold pressing), suggesting that the SFE technique better preserves the phenolic compounds present in the seed, which are likely responsible for the antioxidant nature of the oil. In vitro tests with the sample displaying the best antioxidant response were conducted in rat liver homogenate to investigate the inhibition of spontaneous lipid peroxidation or autooxidation of biological tissue. Linseed oil proved to be more efficient than fish oil (used as standard) in decreasing lipid peroxidation in the liver tissue of Wistar rats, yielding similar results to those obtained with the use of BHT (synthetic antioxidant). Inhibitory capacity may be explained by the presence of phenolic compounds with antioxidant activity in the linseed oil. The results obtained indicate the need for more detailed studies, given the importance of linseed oil as one of the greatest sources of ω3 among vegetable oils / O presente trabalho teve como objetivo geral extrair o ?leo vegetal da linha?a (Linum usitatissimum L.) da variedade marrom fazendo uso de di?xido de carbono em condi??es supercr?ticas e de solvente org?nico, avaliar os teores de ?cidos graxos e a capacidade antioxidante do ?leo extra?do e ainda realizar a avalia??o econ?mica r?pida do processo EFS de manufatura do ?leo. Os experimentos foram conduzidos em um extrator de bancada, capaz de operar com di?xido de carbono e co-solventes, obedecendo a um planejamento fatorial 2? com triplicata no ponto central, tendo como vari?vel resposta o rendimento do processo e como vari?veis independentes a press?o, a temperatura e o percentual de co-solvente. Os rendimentos (massa de ?leo extra?do/ massa de mat?ria-prima utilizada) variaram de 2,2 a 28,8%, tendo os melhores resultados sido obtidos a 250 bar e 50?C, com uso do co-solvente etanol a 5% (v/v). A influ?ncia das vari?veis sobre a cin?tica de extra??o e sobre a composi??o do ?leo de linha?a obtido tamb?m foi investigada. As curvas cin?ticas de extra??o obtidas foram modeladas por diferentes modelos matem?ticos dispon?veis na literatura. Os modelos de Mart?nez et al. (2003) e o Simple Single Plate (SSP) de Gaspar et al. (2003) representaram os dados experimentais com os menores erros quadr?ticos m?dios (MSE). O custo de manufatura de 17,85 US$/kg?leo foi estimado para produ??o do ?leo de linha?a utilizando o software TECANALYSIS e a metodologia de Rosa e Meireles (2005). Com o intuito de estabelecer compara??es com a EFS, foram realizados ensaios de extra??o por t?cnica convencional em aparato Soxhlet utilizando ?ter de petr?leo. Estes apresentaram rendimentos m?dios de 35,2 % para um tempo de extra??o de 5h. Todas as amostras de ?leo obtidas foram esterificadas e caracterizadas em termos de sua composi??o em ?cidos graxos (AGs) usando a cromatografia gasosa. Os principais ?cidos graxos detectados foram: palm?tico (C16:0), este?rico (C18:0), ol?ico (C18:1), linol?ico (C18:2n-6) e α-linol?nico (C18:3n-3). Os teores dos AGs obtidos com Soxhlet diferiram daqueles obtidos para a EFS, com percentuais de AGs saturados e monoinsaturados mais elevados para a t?cnica Soxhlet com ?ter de petr?leo. Com rela??o ao teor do ?cido α-linol?nico (componente majorit?rio do ?leo de linha?a) nas amostras, a EFS se mostrou mais vantajosa que a extra??o Soxhlet, apresentando percentuais de 51,18 a 52,71%, enquanto que na extra??o Soxhlet, este foi de 47,84%. A atividade antioxidante do ?leo foi avaliada no sistema de co-oxida??o b-caroteno/?cido linol?ico. Os percentuais de inibi??o do processo oxidativo chegaram a 22,11% para o ?leo da EFS, sendo de apenas 6,09% para o ?leo comercial extra?do a frio, o que sugere que a t?cnica EFS preserva melhor os compostos fen?licos presentes na semente, compostos estes, provavelmente respons?veis pelo car?ter antioxidante do ?leo. Testes in vitro com a amostra de melhor resposta antioxidante foram realizados em homogenato de f?gado de ratos, de forma a investigar a inibi??o da peroxida??o lip?dica espont?nea ou autoxida??o do tecido biol?gico. O ?leo de linha?a se mostrou mais eficiente que o ?leo de peixe (usado como padr?o) na diminui??o da peroxida??o lip?dica do tecido hep?tico dos ratos Wistar, apresentando resultados equivalentes aos obtidos com o uso do BHT (antioxidante sint?tico). A capacidade inibit?ria pode ser atribu?da ? presen?a de compostos fen?licos com atividade antioxidante presentes no ?leo de linha?a. Os resultados obtidos indicam a necessidade de estudos mais aprofundados tendo em vista a import?ncia do ?leo de linha?a como uma das maiores fontes de ω3 dentre os ?leos vegetais

Made available in DSpace on 2014-12-17T15:01:57Z (GMT). No. of bitstreams: 1 LeocadiaTCB.pdf: 1594369 bytes, checksum: da7a2bc5860922178cae36e104bfbd40 (MD5) Previous issue date: 2006-10-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Effluent color resulting from textile dyeing processes has been one of the biggest environmental problems faced by the textile industry. In particular, reactive dyes are highly resistant to conventional wastewater treatment methods. New technologies have been contemplated, some of which have been applied in industrial treatment plants, but color removal has not been efficiently attained. Since microemulsion systems provide good results in heavy metals and proteins extraction processes, their use in dyes extraction has been suggested and investigated. In this work, a real textile wastewater from an exhaustion dyebath has been treated, which contains the following reactive dyes: Procion Yellow H-E4R (CI Reactive Yellow 84), Procion Blue H-ERD (CI Reactive Blue 160) and Procion Red H-E3B (CI Reactive Red 120), in addition to auxiliary compounds normally found in dyeing processes with reactive dyes. The dyes Remazol Blue RR and Remazol Turquoise Blue G (Reactive Blue 21) have also been examined in view of the presence of heavy metals in these molecules. The microemulsion system comprised dodecyl ammonium chloride (as a cationic surfactant), water or wastewater as aqueous phase, kerosene as oil phase, and one of the following alcohols as cosurfactant: isoamyl alcohol, n-butyl alcohol and n-octyl alcohol. The pseudo-ternary diagrams were constructed in order to define Winsor s equilibrium regions. The influence of parameters such as pH, C/S (cosurfactant/surfactant) ratio, distribution coefficient, initial dye concentration, salinity, temperature, phases relative amounts, loading capacity of the microemulsion phase and dye reextraction rate has also been investigated. An experimental planning (Scheff? Net) was used to optimize the extraction process. The removal of color and metals reached levels as high as 99% / A cor do efluente resultante dos processos de tingimento tem sido um dos principais problemas ambientais enfrentados pela ind?stria t?xtil. De modo especial, efluentes contendo corantes reativos s?o altamente resistentes aos processos de tratamento convencionais. Novas tecnologias t?m sido buscadas, algumas j? em escala industrial, por?m nem sempre ? poss?vel atingir a efici?ncia desejada. Por serem utilizadas de forma eficiente em processos de extra??o de metais e de prote?nas, buscou-se utilizar as microemuls?es na extra??o de corantes. Para este estudo, um efluente real foi examinado, consistindo no banho de exaust?o de um processo de tingimento contendo os seguintes corantes: Procion Amarelo H-E4R (CI Reactive Yellow 84), Procion Azul H-ERD (CI Reactive Blue 160) e Procion Vermelho H-E3B (CI Reactive Red 120), al?m de auxiliares normalmente encontrados em processos de tingimento com corantes reativos. Para estudar a remo??o de metais ligados ?s mol?culas dos corantes, utilizaram-se ainda os corantes Remazol Azul RR e Remazol Azul Turquesa G (Reactive Blue 21). Os sistemas de microemuls?o foram formados pelo cloreto de dodecilam?nio (tensoativo cati?nico), ?gua ou efluente como fase aquosa, querosene como fase oleosa e um dos seguintes ?lcoois como cotensoativos: ?lcool isoam?lico, n-butanol e n-octanol. Os diagramas pseudo-tern?rios, representativos dos sistemas microemulsionados em estudo, foram desenvolvidos a fim de delimitar as regi?es de exist?ncia de equil?brio de fases (sistema de classifica??o Winsor). Verificou-se a influ?ncia de par?metros como: pH, raz?o C/T (cotensoativo/tensoativo), coeficiente de distribui??o, concentra??o inicial de corante, salinidade, temperatura, rela??o das fases, capacidade de carga da fase de microemuls?o e reextra??o do corante. Uma metodologia de planejamento experimental (Rede de Scheff?) foi utilizada para otimizar a extra??o. A remo??o da cor e de metais alcan?ou ?ndices de extra??o superiores a 99%

Made available in DSpace on 2014-12-17T14:54:49Z (GMT). No. of bitstreams: 1 HelianaBS_da_capa_ate_cap4.pdf: 2361373 bytes, checksum: 3e1e43e8ba1aadc274663b8b8e3de72f (MD5) Previous issue date: 2008-02-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The skin cancer is the most common of all cancers and the increase of its incidence must, in part, caused by the behavior of the people in relation to the exposition to the sun. In Brazil, the non-melanoma skin cancer is the most incident in the majority of the regions. The dermatoscopy and videodermatoscopy are the main types of examinations for the diagnosis of dermatological illnesses of the skin. The field that involves the use of computational tools to help or follow medical diagnosis in dermatological injuries is seen as very recent. Some methods had been proposed for automatic classification of pathology of the skin using images. The present work has the objective to present a new intelligent methodology for analysis and classification of skin cancer images, based on the techniques of digital processing of images for extraction of color characteristics, forms and texture, using Wavelet Packet Transform (WPT) and learning techniques called Support Vector Machine (SVM). The Wavelet Packet Transform is applied for extraction of texture characteristics in the images. The WPT consists of a set of base functions that represents the image in different bands of frequency, each one with distinct resolutions corresponding to each scale. Moreover, the characteristics of color of the injury are also computed that are dependants of a visual context, influenced for the existing colors in its surround, and the attributes of form through the Fourier describers. The Support Vector Machine is used for the classification task, which is based on the minimization principles of the structural risk, coming from the statistical learning theory. The SVM has the objective to construct optimum hyperplanes that represent the separation between classes. The generated hyperplane is determined by a subset of the classes, called support vectors. For the used database in this work, the results had revealed a good performance getting a global rightness of 92,73% for melanoma, and 86% for non-melanoma and benign injuries. The extracted describers and the SVM classifier became a method capable to recognize and to classify the analyzed skin injuries / O c?ncer de pele ? o mais comum de todos os c?nceres e o aumento da sua incid?ncia deve-se, em parte, ao comportamento das pessoas em rela??o ? exposi??o ao sol. No Brasil, o c?ncer de pele n?o melanoma ? o mais incidente na maioria das regi?es. A dermatoscopia e ideodermatoscopia s?o os principais tipos de exames para o diagn?stico de doen?as da pele dermatol?gicas. O campo que envolve o uso de ferramentas computacionais para o aux?lio ou acompanhamento do diagn?stico m?dico em les?es dermatol?gicas ainda ? visto como muito recente. V?rios m?todos foram propostos para classifica??o autom?tica de patologias da pele utilizando imagens. O presente trabalho tem como objetivo apresentar uma nova metodologia inteligente para an?lise e classifica??o de imagens de c?ncer de pele, baseada nas t?cnicas de processamento digital de imagens para extra??o de caracter?sticas de cor, forma e textura, utilizando a Transformada Wavelet Packet (TWP) e a t?cnicas de aprendizado de m?quina denominada M?quina de Vetor de Suporte (SVM Support Vector Machine). A Transformada Wavelet Packet ? aplicada para extra??o de caracter?sticas de textura nas imagens. Esta consiste de um conjunto de fun??es base que representa a imagem em diferentes bandas de freq??ncia, cada uma com resolu??es distintas correspondente a cada escala. Al?m disso, s?o calculadas tamb?m as caracter?sticas de cor da les?o que s?o dependentes de um contexto visual, influenciada pelas cores existentes em sua volta, e os atributos de forma atrav?s dos descritores de Fourier. Para a tarefa de classifica??o ? utilizado a M?quina de Vetor de Suporte, que baseia-se nos princ?pios da minimiza??o do risco estrutural, proveniente da teoria do aprendizado estat?stico. A SVM tem como objetivo construir hiperplanos ?timos que apresentem a maior margem de separa??o entre classes. O hiperplano gerado ? determinado por um subconjunto dos pontos das classes, chamado vetores de suporte. Para o banco de dados utilizado neste trabalho, os resultados apresentaram um bom desempenho obtendo um acerto global de 92,73% para melanoma, e 86% para les?es n?o-melanoma e benigna. O potencial dos descritores extra?dos aliados ao classificador SVM tornou o m?todo capaz de reconhecer e classificar as les?es analisadas