Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-03-15T18:26:06Z No. of bitstreams: 1 MARCELO_MATOS_ROCHA_DIS.pdf: 2694699 bytes, checksum: b35320c3e1bad1e5215967015213d4c2 (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-03-28T12:16:11Z (GMT) No. of bitstreams: 1 MARCELO_MATOS_ROCHA_DIS.pdf: 2694699 bytes, checksum: b35320c3e1bad1e5215967015213d4c2 (MD5) / Made available in DSpace on 2018-03-28T12:29:33Z (GMT). No. of bitstreams: 1 MARCELO_MATOS_ROCHA_DIS.pdf: 2694699 bytes, checksum: b35320c3e1bad1e5215967015213d4c2 (MD5) Previous issue date: 2018-01-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Bisphosphonates have been associated with medication-related osteonecrosis of the jaw (MRONJ), a disorder that has some risk factors such as surgical interventions in the jaw bones, especially tooth extractions. On the other hand, xenogeneic grafts have been widely used to fill the alveolar socket after tooth extraction, with clinical evidences of improving local conditions of the surgical bed for oral rehabilitation. The aim of this study was to investigate the effect of combined bisphosphonate and the xenogeneic graft Bio-Oss? Collagen on alveolar bone repair after tooth extraction. Sixty rats were allocated into five groups according to the treatment received: zoledronic acid (group 1) and alendronate (group 2) both with xenogeneic graft; zoledronic acid (group 3) and alendronate (group 4) both without xenogeneic graft; and control (group 5). All animals were subjected to tooth extractions, and maxillae were dissected and macro- and microscopically analyzed. Frequency of oral mucosal wounds did not significantly differ between the groups; however, these lesions were significantly smaller in the control group. The amount of fibrous connective tissue was greater in groups 2 (alendronate/Bio-Oss) and 5 (control) than in 3 (zoledronic acid) and 4 (alendronate). Group 4 showed greater amounts of vital bone than did groups 1 (zoledronic acid/Bio-Oss), 3 and 5. The amounts of non-vital bone were greater in the zoledronic acid groups (1 and 3), where non-vital bone was less in group 1 than 3. Group 3 showed more inflammatory infiltrate than groups 2, 4 and 5. There were greater amounts of microbial colonies in group 3. Inflammatory infiltrate and microbial colonies were negatively correlated to vital bone and positively correlated to non-vital bone. Inflammatory infiltrate and microbial colonies were positively correlated to each other. Conclusion: Post-extraction socket filling with Bio-Oss? Collagen did not prevent the occurrence of non-vital bone and infection, but it did lower the extent of these variables in rats under treatment with zoledronic acid. / Os bisfosfonatos t?m sido associados ? ocorr?ncia de osteonecrose maxilar (MRONJ, medication-related osteonecrosis of the jaw), condi??o que tem, entre os fatores de risco para sua ocorr?ncia, as interven??es cir?rgicas dos ossos maxilares, principalmente as exodontias. Por outro lado, o uso de xenoenxerto para preenchimento alveolar ap?s exodontia tornou-se procedimento frequente, com evid?ncias cl?nicas de sua capacidade em melhorar as condi??es locais do s?tio cir?rgico com vistas ? reabilita??o oral. O presente estudo teve por objetivo investigar o efeito do uso combinado de bisfosfonato e enxerto xen?geno (Bio-Oss?Collagen) no reparo ?sseo alveolar ap?s exodontia. Sessenta ratos foram distribu?dos em cinco grupos de acordo com o tratamento recebido: ?cido zoledr?nico (grupo 1) e alendronato (grupo 2), ambos com xenoenxerto; ?cido zoledr?nico (grupo 3) e alendronato (grupo 4), ambos sem xenoenxerto; e grupo-controle (grupo 5). Todos os animais foram submetidos a exodontias, as maxilas foram dissecadas e analisadas por meio de exame macro- e microsc?pico. A frequ?ncia de les?o da mucosa oral n?o diferiu significativamente entre os grupos; entretanto essas les?es foram significativamente menores no grupo-controle. A preval?ncia de tecido conjuntivo fibroso foi maior nos grupos 2 (alendronato/Bio-Oss) e 5 (controle) do que nos grupos 3 (?cido zoledr?nico) e 4 (alendronato). O grupo 4 (alendronato) teve maior quantidade de osso vital do que os grupos 1 (?cido zoledr?nico/Bio-Oss), 3 (?cido zoledr?nico) e controle. A quantidade de osso n?o-vital foi maior nos grupos ?cido zoledr?nico com e sem Bio-Oss (1 and 3), sendo que, ao comparar-se esses dois grupos entre si, essa vari?vel foi maior no grupo 3. O grupo 3 exibiu mais infiltrado inflamat?rio do que os grupos 2, 4 e 5 e maior quantidade de col?nias microbianas do que os demais grupos. Infiltrado inflamat?rio e col?nias microbianas tiveram correla??o negativa com osso vital e positiva com osso n?o-vital. Infiltrado inflamat?rio e col?nias microbianas exibiram correla??o positiva entre si. Conclus?o: O preenchimento do alv?olo p?s-exodontia com Bio-Oss? Collagen n?o evitou a ocorr?ncia de osso n?o-vital e infec??o, mas foi capaz de diminuir a intensidade dessas vari?veis nos ratos sob tratamento com ?cido zoledr?nico.

Submitted by PPG Ci?ncia da Computa??o (ppgcc@pucrs.br) on 2018-06-19T11:37:24Z No. of bitstreams: 1 EVANDRO BRASIL FONSECA_TES.pdf: 1972824 bytes, checksum: 9fca0c499753cd9d2822c59040e826bf (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-26T14:40:39Z (GMT) No. of bitstreams: 1 EVANDRO BRASIL FONSECA_TES.pdf: 1972824 bytes, checksum: 9fca0c499753cd9d2822c59040e826bf (MD5) / Made available in DSpace on 2018-06-26T14:48:46Z (GMT). No. of bitstreams: 1 EVANDRO BRASIL FONSECA_TES.pdf: 1972824 bytes, checksum: 9fca0c499753cd9d2822c59040e826bf (MD5) Previous issue date: 2018-03-19 / Coreference Resolution task is challenging for Natural Language Processing, considering the required linguistic knowledge and the sophistication of language processing techniques involved. Even though it is a demanding task, a motivating factor in the study of this phenomenon is its usefulness. Basically, several Natural Language Processing tasks may benefit from their results, such as named entities recognition, relation extraction between named entities, summarization, sentiment analysis, among others. Coreference Resolution is a process that consists on identifying certain terms and expressions that refer to the same entity. For example, in the sentence ? France is refusing. The country is one of the first in the ranking... ? we can say that [the country] is a coreference of [France]. By grouping these referential terms, we form coreference groups, more commonly known as coreference chains. This thesis proposes a process for coreference resolution between noun phrases for Portuguese, focusing on the use of semantic knowledge. Our proposed approach is based on syntactic-semantic linguistic rules. That is, we combine different levels of linguistic processing, using semantic relations as support, in order to infer referential relations between mentions. Models based on linguistic rules have been efficiently applied in other languages, such as: English, Spanish and Galician. In few words, these models are more efficient than machine learning approaches when we deal with less resourceful languages, since the lack of sample-rich corpora may produce a poor training. The proposed approach is the first model for Portuguese coreference resolution which uses semantic knowledge. Thus, we consider it as the main contribution of this thesis. / A tarefa de Resolu??o de Correfer?ncia ? um grande desafio para a ?rea de Processamento da Linguagem Natural, tendo em vista o conhecimento lingu?stico exigido e a sofistica??o das t?cnicas de processamento da l?ngua empregados. Mesmo sendo uma tarefa desafiadora, um fator motivador do estudo deste fen?meno se d? pela sua utilidade. Basicamente, v?rias tarefas de Processamento da Linguagem Natural podem se beneficiar de seus resultados, como, por exemplo, o reconhecimento de entidades nomeadas, extra??o de rela??o entre entidades nomeadas, sumariza??o, an?lise de sentimentos, entre outras. A Resolu??o de Correfer?ncia ? um processo que consiste em identificar determinados termos e express?es que remetem a uma mesma entidade. Por exemplo, na senten?a ?A Fran?a est? resistindo. O pa?s ? um dos primeiros no ranking...? podemos dizer que [o pa?s] ? uma correfer?ncia de [A Fran?a]. Realizando o agrupamento desses termos referenciais, formamos grupos de men??es correferentes, mais conhecidos como cadeias de correfer?ncia. Esta tese prop?e um processo para a resolu??o de correfer?ncia entre sintagmas nominais para a l?ngua portuguesa, tendo como foco a utiliza??o do conhecimento sem?ntico. Nossa abordagem proposta ? baseada em regras lingu?sticas sint?tico-sem?nticas. Ou seja, combinamos diferentes n?veis de processamento lingu?stico utilizando rela??es sem?nticas como apoio, de forma a inferir rela??es referenciais entre men??es. Modelos baseados em regras lingu?sticas t?m sido aplicados eficientemente em outros idiomas como o ingl?s, o espanhol e o galego. Esses modelos mostram-se mais eficientes que os baseados em aprendizado de m?quina quando lidamos com idiomas menos providos de recursos, dado que a aus?ncia de corpora ricos em amostras pode prejudicar o treino desses modelos. O modelo proposto nesta tese ? o primeiro voltado para a resolu??o de correfer?ncia em portugu?s que faz uso de conhecimento sem?ntico. Dessa forma, tomamos este fator como a principal contribui??o deste trabalho.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-03-28T11:33:08Z No. of bitstreams: 1 DIS_PATRICIA_CARVALHO_ALMEIDA_COMPLETO.pdf: 1695882 bytes, checksum: 485e636dfb13c1dacc99571a2309aa50 (MD5) / Made available in DSpace on 2016-03-28T11:33:08Z (GMT). No. of bitstreams: 1 DIS_PATRICIA_CARVALHO_ALMEIDA_COMPLETO.pdf: 1695882 bytes, checksum: 485e636dfb13c1dacc99571a2309aa50 (MD5) Previous issue date: 2015-11-30 / Extracts obtained from natural products have attracted the interest of pharmacological sector due to the chemical and biological properties. Therefore, in this work were studied the chromenes (precocene I and II) extraction processes, steam distillation and supercritical fluid extraction (SFE), from Ageratum conyzoides L. Essential oil was extracted by saturated steam at 1.0, 1.5, and 2.0 bar and the supercritical fluid extractions were performed at 40?C and 90, 120, 150, and 200 bar to obtain non-volatile extracts. The essential oils were analyzed by gas chromatography/mass spectroscopy while the non-volatile extracts composition was determined by high-performance liquid chromatography. The essential oil presented two major compounds, precocene I (28.24 ? 2.64%) and precocene II (28.55 ? 2.08%). At 90 bar, the SFE resulted in higher yield and selectivity for precocene I and II, which represent 65.06% of extract. It was observed that the yield of chromenes varies according to pressure of SFE, however this behavior was not observed in the extracts obtained by steam distillation. A mathematical model was also used to simulate the processes and a good correlation was attained with the experimental data. / Extratos obtidos a partir de produtos naturais t?m atra?do o interesse do setor farmacol?gico devido ?s propriedades qu?micas e biol?gicas. Portanto, neste trabalho foram estudados os processos de extra??o de cromenos (precoceno I e II), destila??o a vapor e extra??o com fluido supercr?tico (SFE), a partir de Ageratum conyzoides L. O ?leo essencial foi extra?do por vapor saturado a 1,0, 1,5, e 2,0 bar e as extra??es com fluido supercr?tico foram realizadas a 40?C e 90, 120, 150, e 200 bar para obter extratos n?o vol?teis. Os ?leos essenciais foram analisados por cromatografia gasosa e espectroscopia de massa, enquanto que a composi??o dos n?o-vol?teis extratos foi determinada por cromatografia l?quida de alta efici?ncia. O ?leo essencial apresentou dois compostos principais, precoceno I (28,24 ? 2,64%) e precoceno II (28,55 ? 2,08%). A 90 bar, a SFE resultou em maior rendimento e seletividade para os precoceno I e II, que representaram 65,06% do extrato. Observou-se que o rendimento de cromenos varia de acordo com a press?o da SFE, no entanto, isto n?o foi observado nos extratos obtidos por meio de destila??o a vapor. Um modelo matem?tico tamb?m foi usado para simular os processos e uma boa correla??o foi obtida com os dados experimentais.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-09-12T16:18:06Z No. of bitstreams: 1 TES_MANUEL_ALVES_FALCAO_COMPLETO.pdf: 3543313 bytes, checksum: c6209bccf7d4cd318c874850a1bc853d (MD5) / Made available in DSpace on 2016-09-12T16:18:06Z (GMT). No. of bitstreams: 1 TES_MANUEL_ALVES_FALCAO_COMPLETO.pdf: 3543313 bytes, checksum: c6209bccf7d4cd318c874850a1bc853d (MD5) Previous issue date: 2016-03-30 / Chemotherapy is highlighted for the treatment of many classes of tumors, especially by new drug delivery nanosystems. The drug delivery nanosystems are focused on greater selectivity for abnormal tissue, decrease adverse effects, dose reduction and decreased frequency applications. Due to the scale of these systems, the EPR effect favors the permeabilization in blood vessels and retention in tumor tissue particles. This thesis performed vinblastine extractions from C. roseus using water and ethanol as co-solvents for CO2 at 300 bar and at different temperatures, those experiments showed the viability of this extraction method, subsequent extractions were optimized using ethanol. The results are compared to traditional extraction methods such as solid-liquid extraction the results found was up to 92.41%. Concluding that vinblastine extraction using carbon dioxide and ethanol mixtures at high pressure is possible. The PLGA nanoparticles containing vinblastine showed again the reproducibility of the nanoemulsion method of ensuring the production of homogeneous nanoparticles with and without drug and cell viability experiments show that the three formulations of PLGA nanoparticles containing vinblastine potentiated drug activity at the lower doses, 1 and 5 ?g/mL, compared to free drug. The studies of glycopolymers synthesis presented the novel synthesis of an ATRP initiator based on PLGA without using PEG spacers. This initiator may, in future studies, be used for modifying PLGA. Successive attempts monomer polymerization saccharide via ATRP in water and DMSO leads to the conclusion that this approach is not the most suitable for the syntheses of glycopolymers graft from a PLGA initiator without the use of PEG spacers. / A quimioterapia ? op??o terap?utica para o tratamento de diversas classes de tumores, principalmente pelos novos nanosistemas de libera??o modificada de f?rmacos. Os nanosistemas de libera??o modificada t?m como foco a maior seletividade aos tecidos anormais, a diminui??o de efeitos adversos, redu??o da dose e diminui??o da frequ?ncia de aplica??es. Devido a escala destes sistemas, o efeito EPR favorece a permeabiliza??o nos vasos sangu?neos e a reten??o de part?culas no tecido tumoral. Nesta tese foram realizadas extra??es de vimblastina a partir de C. roseus utilizando ?gua e etanol como cossolventes de CO2 a 300 bar e a diferentes temperaturas mostraram a viabilidade do m?todo de extra??o, posteriormente, as extra??es foram otimizadas utilizando etanol. Quando os resultados encontrados s?o comparados a m?todos tradicionais de extra??o como a extra??o s?lido-l?quido o resultado encontrado foi de at? 92,41% superior. Concluindo, que a extra??o de vimblastina utilizando misturas de di?xido de carbono e etanol a altas press?es ? poss?vel. As nanopart?culas de PLGA contendo vimblastina demonstraram a reprodutibilidade do m?todo de nanoemuls?o garantindo a produ??o de nanopart?culas homog?neas, com e sem f?rmaco. Os experimentos de viabilidade celular mostraram que as tr?s formula??es de nanopart?culas de PLGA contendo vimblastina potencializaram a atividade do f?rmaco para as doses mais baixas, 1 e 5 ?g/mL, em rela??o ao f?rmaco livre. Os estudos realizados de s?ntese de glicopol?meros apresentaram a s?ntese in?dita de um iniciador de ATRP baseado em PLGA sem o uso de espa?adores de PEG. Este iniciador pode, em futuros estudos, ser utilizado para a modifica??o de PLGA. As sucessivas tentativas de polimeriza??o de mon?meros de sacar?deos via ATRP em ?gua e DMSO leva a conclus?o que esta metodologia n?o ? a mais adequada para s?nteses glicopol?meros conjugados a PLGA sem o uso de espa?adores de PEG.

?rea de concentra??o: Produ??o Vegetal. / Submitted by Alexandre Soares (alexandredesoares@yahoo.com.br) on 2016-08-25T12:37:54Z No. of bitstreams: 1 barbara_olinda_nardis.pdf: 810097 bytes, checksum: 27e96d5c3c22fb510620ee61aed0d5f0 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-09-08T17:35:09Z (GMT) No. of bitstreams: 1 barbara_olinda_nardis.pdf: 810097 bytes, checksum: 27e96d5c3c22fb510620ee61aed0d5f0 (MD5) / Made available in DSpace on 2016-09-08T17:35:09Z (GMT). No. of bitstreams: 1 barbara_olinda_nardis.pdf: 810097 bytes, checksum: 27e96d5c3c22fb510620ee61aed0d5f0 (MD5) Previous issue date: 2015 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Coordenadoria de Aperfei?oamento do Pessoal de N?vel Superior (Capes) / O zinco ? um micronutriente importante para o crescimento das plantas, mas pode ser um problema quando presente em grandes quantidades, sendo a extra??o sequencial uma ferramenta promissora para se entender melhor o comportamento do Zn no solo. Objetivou-se com este trabalho observar o crescimento, a absor??o e o ac?mulo de Zn em cinco gram?neas forrageiras e entender o comportamento do Zn no solo ap?s o cultivo. Realizou-se um experimento em casa de vegeta??o em Latossolo Vermelho-Amarelo distr?fico. O delineamento foi inteiramente casualizado em esquema fatorial 5x4 com tr?s repeti??es, sendo os fatores: gram?neas forrageiras (Panicum maximum cv. Aruana e cv. Tanz?nia, Brachiaria decumbens cv. Basilisk, Brachiaria brizantha cv. Xara?s e cv. Marandu) e doses (0, 100, 300 e 900 mg kg-1 de Zn). O material vegetal coletado foi analisado separadamente, obtendo-se o peso de massa seca da parte a?rea, do coleto e das ra?zes e analisado o teor e ac?mulo de Zn em cada parte. Avaliou-se a disponibilidade de Zn atrav?s dos extratores Mehlich-1, DTPA a pH 7,3, USEPA 3051 e 3052 e o comportamento do Zn no solo foi avaliado atrav?s da extra??o sequencial do Zn analisando as fra??es troc?vel, ligada a carbonato, ligada a mat?ria org?nica, ligada a ?xidos, residual e total. As doses de Zn no solo provocaram redu??o de crescimento em todas as forrageiras avaliadas. Para a produ??o de massa seca a cv. Aruana foi a que mais produziu massa seca. Os maiores teores de Zn foram encontrados nas ra?zes da Tanz?nia e Marandu e na parte a?rea de Aruana, Xara?s e Basilisk. A ordem de acumula??o das forrageiras foram Aruana > Basilisk > Tanz?nia > Xara?s > Marandu. No geral a cv. Aruana se mostrou melhor para extrair Zn do solo. A ordem de extra??o foi DTPA a pH 7,3 < Mehlich-1 < USEPA 3051 < USEPA 3052, sendo que a metodologia USEPA 3051 mostrou resultados semelhante ao Mehlich-1, portanto eficiente em demonstrar a disponibilidade do Zn no solo. A distribui??o de Zn entre as fra??es no solo foi residual > carbonato > troc?vel > mat?ria org?nica > ?xidos. / Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / Zinc is an important micronutrient to plant growth, but it can be problem when present in large amountsbeing the sequential extraction a promising tool to better understand the behavior of Zn in the soil. The objective of this study was to observe the growth, Zn absorption and accumulation in five forage grasses and to understand the behavior of Zn in soil after cultivation. We conducted an experiment in a greenhouse in Red-Yellow Dystrophic Latosol. The design was completely randomized in a factorial scheme 5x4 with three replicates, being the factors: forage grasses (Panicum maximum cv. Aruana e cv. Tanz?nia, Brachiaria decumbens cv. Basilisk, Brachiaria brizantha cv. Xara?s e cv. Marandu) and doses (0, 100, 300 e 900 mg kg-1 of Zn). The collected plant material was analyzed separately to obtain the dry matter weight of the shoot, the collar and roots and analyzed the content and Zn accumulation in each part. We evaluated the Zn availability using the extractors Mehlich-1, DTPA with pH 7,3, USEPA 3051 and 3052 and Zn behavior in the soil was evaluated by Zn sequential extraction analyzing the exchangeable fractions, linked to carbonate,to the organic matter and to oxides, residual and total. The doses of Zn in soil caused growth reduction in all forages. For dry matter production Aruana cv. was the one that most produced dry matter. The higher levels of Zn were found in the roots of Tanzania and Marandu and also in the shoots of Aruana, Xara?s and Basilisk. The order of accumulation of forage was Aruana > Basilisk > Tanz?nia > Xara?s > Marandu. Overall Aruana cv. proved to be the best to extract Zn from the soil. The order of extraction was DTPA with pH 7,3 < Mehlich-1 < USEPA 3051 < USEPA 3052, whereas the 3051 USEPA methodology showed results similar to Mehlich-1, therefore efficient in demonstrating the availability of Zn in soil. The distribution of Zn between fractions in the soil was residual> carbonate> exchangeable> organic matter> oxides.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-01T21:27:07Z No. of bitstreams: 1 EmilyCintiaTossiDeAraujoCosta_TESE.pdf: 2216846 bytes, checksum: 5f38e382d8ae3c1bfe9f3db58b62a672 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2016-02-02T21:24:40Z (GMT) No. of bitstreams: 1 EmilyCintiaTossiDeAraujoCosta_TESE.pdf: 2216846 bytes, checksum: 5f38e382d8ae3c1bfe9f3db58b62a672 (MD5) / Made available in DSpace on 2016-02-02T21:24:40Z (GMT). No. of bitstreams: 1 EmilyCintiaTossiDeAraujoCosta_TESE.pdf: 2216846 bytes, checksum: 5f38e382d8ae3c1bfe9f3db58b62a672 (MD5) Previous issue date: 2013-09-23 / A contamina??o de ?guas naturais por metais tornou-se assunto de interesse p?blico mundial por serem considerados biocumulativos. A determina??o e o monitoramento de contaminantes met?licos em ?guas ? uma tarefa que deve ser cont?nua e por isto a import?ncia do desenvolvimento, modifica??o e otimiza??o de metodologias anal?ticas capazes de realizar a determina??o dos v?rios contaminantes met?licos em ambientes naturais, pois em muitos casos, a instrumenta??o dispon?vel n?o apresenta sensibilidade anal?tica suficiente para a determina??o de tra?os. Neste estudo, um m?todo de extra??o e pr?-concentra??o utilizando um sistema microemulsionado, no equil?brio de Winsor II foi testado e otimizado para a determina??o dos metais Co, Cd, Pb, Tl, Cu e Ni por Espectrometria de absor??o at?mica de alta resolu??o com fonte cont?nua e atomiza??o em forno de grafite e chama (HR-CS AAS). A otimiza??o do programa de temperatura para o forno de grafite foi realizada atrav?s de curvas de pir?lise e atomiza??o para cada analito sem e com o uso de diferentes modificadores qu?micos. Cd e Pb tiveram condi??es ?timas com modificador permanente Ru, pir?lise em 700?C e atomiza??o em 1700?C, para Tl solu??o Pd/Mg foi o melhor modificador, temperaturas 600?C e 1700?C de pir?lise e atomiza??o, respectivamente e para o Co pir?lise em 800?C e atomiza??o ? 2400?C sem uso de modificador qu?mico, por?m W foi empregado como modificador permanente a fim de se prolongar o tempo de vida ?til do forno. Cu e Ni foram analisados na chama ap?s pr?-concentra??o. Avaliou-se tamb?m fatores que influenciam a efici?ncia de extra??o, atrav?s do efeito salting out. Como compromisso, 6 g L-1 de Na e 1% de HNO3 (v/v) foi definido. Para determina??o do ponto ?timo de extra??o, um planejamento centroide-simplex foi aplicado, sendo escolhido como compromisso as seguintes propor??es: 70% fase aquosa, 10% fase ?leo e 20% Cotensoativo/Tensoativo (C/T = 4). Ap?s extra??o, os metais foram determinados e as Figuras de m?rito obtidas para o m?todo proposto foi: 0,1 a 10 ?g L-1 de faixa linear, LOD 0,094, 0,011, 0,057 e 0,050 ?g L-1 para Pb, Cd, Tl e Co, respectivamente. Testes de adi??o e recupera??o na amostra certificada apresentaram valores de recupera??o ap?s extra??o de 105 e 101% para Pb e Cd, respectivamente, e nas amostras fortificadas a recupera??o para os analitos ficou entre 107 e 108% comprovando que o m?todo proposto pode ser utilizado na extra??o, possibilitou a separa??o dos metais de matrizes complexas, e ainda com bom fator de pr?-concentra??o. / The determination and monitoring of metallic contaminants in water is a task that must be continuous, leading to the importance of the development, modification and optimization of analytical methodologies capab le of determining the various metal contaminants in natural environments, because, in many cases, the ava ilable instrumentation does not provide enough sensibility for the determination of trace values . In this study, a method of extraction and pre- concentration using a microemulsion system with in the Winsor II equilibrium was tested and optimized for the determination of Co, Cd, P b, Tl, Cu and Ni through the technique of high- resolution atomic absorption spectrometry using a continuum source (HR-CS AAS). The optimization of the temperature program for the graphite furnace (HR-CS AAS GF) was performed through the pyrolysis and atomization curves for the analytes Cd, Pb, Co and Tl with and without the use of different chemical modifiers. Cu and Ni we re analyzed by flame atomization (HR-CS F AAS) after pre-concentr ation, having the sample introduction system optimized for the realization of discrete sampling. Salinity and pH levels were also analyzed as influencing factors in the efficiency of the extraction. As final numbers, 6 g L -1 of Na (as NaCl) and 1% of HNO 3 (v/v) were defined. For the determination of the optimum extraction point, a centroid-simplex statistical plan was a pplied, having chosen as the optimum points of extraction for all of the analytes, the follo wing proportions: 70% aqueous phase, 10% oil phase and 20% co-surfactant/surfactant (C/S = 4). After extraction, the metals were determined and the merit figures obtained for the proposed method were: LOD 0,09, 0,01, 0,06, 0,05, 0,6 and 1,5 ?g L -1 for Pb, Cd, Tl, Co, Cu and Ni, re spectively. Line ar ranges of ,1- 2,0 ?g L -1 for Pb, 0,01-2,0 ?g L -1 for Cd, 1,0 - 20 ?g L -1 for Tl, 0,1-5,0 ?g L -1 for Co, 2-200 ?g L -1 and for Cu e Ni 5-200 ?g L -1 were obtained. The enrichment factors obtained ranged between 6 and 19. Recovery testing with the certified sample show ed recovery values (n = 3, certified values) after extraction of 105 and 101, 100 and 104% for Pb, Cd, Cu and Ni respectively. Samples of sweet waters of lake Jiqui, saline water from Potengi river and water produced from the oil industry (PETROBRAS) were spiked and the recovery (n = 3) for the analytes were between 80 and 112% confirming th at the proposed method can be used in the extraction. The proposed method enabled the sepa ration of metals from complex matrices, and with good pre-concentration factor, consistent with the MPV (allowed limits) compared to CONAMA Resolution No. 357/2005 which regulat es the quality of fresh surface water, brackish and saline water in Brazil.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-09T23:31:45Z No. of bitstreams: 1 DanielNobreNunesDaSilva_DISSERT.pdf: 1373140 bytes, checksum: be843c5287aad6e511b26eef9e599382 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-11T23:38:54Z (GMT) No. of bitstreams: 1 DanielNobreNunesDaSilva_DISSERT.pdf: 1373140 bytes, checksum: be843c5287aad6e511b26eef9e599382 (MD5) / Made available in DSpace on 2016-03-11T23:38:54Z (GMT). No. of bitstreams: 1 DanielNobreNunesDaSilva_DISSERT.pdf: 1373140 bytes, checksum: be843c5287aad6e511b26eef9e599382 (MD5) Previous issue date: 2015-02-04 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A ind?stria do petr?leo ? uma das atividades que mais gera res?duos ao meio ambiente. O cascalho de perfura??o ? um res?duo gerado em grande quantidade no processo de perfura??o de po?os e que pode provocar impactos ambientais, tais como a contamina??o do solo e consequentemente a contamina??o de len??is fre?ticos, caso descartados sem tratamento pr?vio. Surge ? necessidade de se desenvolver atividades cient?ficas e de pesquisar maneiras de adequar esses res?duos as normas ambientais vigentes. No caso dos res?duos s?lidos, a norma NBR 10004:2004 da Associa??o Brasileira de Normas T?cnicas (ABNT) classifica-os em res?duos classe I (perigoso) e classe II (n?o perigoso), onde estabelece quais os res?duos que podem ou n?o ser descartados no meio ambiente sem provocar impacto ambiental. Este trabalho apresenta uma inovadora alternativa para tratar o cascalho de perfura??o, que ? classificado como res?duo classe I (Abreu & Souza, 2005), removendo principalmente a n-parafina presente no mesmo, uma vez que este ? originado quando se usa fluidos de perfura??o base ?leo. Utilizando sistemas microemulsionados promove-se a remo??o deste contaminante de amostras de cascalho de perfura??o provenientes de po?os localizados em Alto do Rodrigues ? RN. Inicialmente, determinou-se a concentra??o de parafina utilizando o m?todo de infravermelho, em amostras previamente extra?das com ultrassom, obteve-se uma concentra??o de parafina na faixa de 36,59 a 43,52 g de parafina por quilograma de cascalho. Utilizou-se dois sistemas microemulsionados contendo dois tensoativos n?o i?nicos de diferentes classes, um ? um ?lcool etoxilado (UNTL-90) e o outro um nonifenol etoxilado (RNX 110). Os resultados indicaram que o sistema com tensoativo UNTL-90 possui melhor efici?ncia que o sistema com RNX 110. O estudo da influ?ncia do tempo de contato na extra??o mostrou que para tempos maiores que 25 minutos tem-se uma tend?ncia ao aumento do percentual de extra??o com o aumento do tempo de contato. Observou-se tamb?m que a extra??o ? r?pida, pois em 1 minutos de contato tem-se 22,7 % de extra??o. A reutiliza??o do sistema microemulsionado, sem a remo??o da parafina extra?da em etapas anteriores, mostrou redu??o de 29,32 no percentual de extra??o comparando a primeira e a terceira extra??o, mas comparando a primeira e segunda extra??es a redu??o ? de 8,5 no percentual de extra??o, logo a otimiza??o da reutiliza??o dos sistemas pode ser uma op??o para viabilizar economicamente a remo??o de parafina de cascalho. A extra??o com agita??o se mostrou mais eficaz no tratamento do cascalho, atingindo o percentual de extra??o de 87,04 %, ou seja, se obt?m um cascalho de perfura??o com 0,551 % de parafina. Utilizando o percentual de parafina empregado nos fluidos de perfura??o n?o aquosos e o limite m?ximo de fluido no cascalho para descarte estabelecido pela Ag?ncia de Prote??o Ambiental dos Estados Unidos (US Environmental Protection Agency - US EPA), chega-se ? conclus?o que o teor de parafina no cascalho n?o pode ser superior a 3,93 %. Conclui-se que a quantidade de parafina no cascalho tratado com o sistema microemulsionado e com agita??o est? bem abaixo do estabelecido pelo ?rg?o americano (US EPA), mostrando que o sistema microemulsionado utilizado foi eficiente na remo??o da parafina do cascalho de perfura??o. / The oil industry is one of the activities that generates more waste to the environment. The drill cuttings is a waste generated in large quantities in the drilling process and that may cause environmental damage such as soil contamination and consequently the contamination of groundwater if disposed of without prior treatment. Arises the need to develop scientific activities and research ways to adapt these wastes the current environmental standards. In the case of solid wastes, the NBR 10004: 2004 of the Brazilian Association of Technical Standards (ABNT) classifies them into class I waste (hazardous) and class II (not dangerous), which determines which wastes may or may not be discarded in the environment without causing environmental impact. This study presents a novel alternative for treating drill cuttings, where this waste was classified as class I (Abreu & Souza, 2005), mainly by removing the n-paraffin present in it, since this arises when using drilling fluids base oil. Using microemulsion systems promotes the removal of this contaminant drill cuttings samples from wells located in Alto do Rodrigues - RN. Initially, we determined the concentration of paraffin using infrared method in samples were extracted with ultrasound, we obtained a paraffin concentration in the range from 36.59 to 43.52 g of paraffin per kilogram of cuttings. Used two microemulsion systems containing two nonionic surfactants from different classes, one is an alcohol ethoxylated (UNTL-90) and the other an nonylphenol ethoxylated (RNX 110). The results indicated that the system UNTL-90 surfactant has better efficiency than the system with RNX 110. The study of the influence of contact time at the extraction showed that for times greater than 25 minutes has a tendency to increase the percentage extraction with increasing contact time. It was also observed that the extraction is fast because at 1 minute contact has 22.7% extraction. The reuse of the microemulsion system without removing the paraffin extracted in previous steps, showed reduction of 29.32 in percentage of extraction by comparing the first and third extraction, but by comparing the first and second extractions reduction is 8.5 in percentage extraction, so the systems reuse optimization can be an option for economically viable removing paraffin from cuttings. The extraction with shaking is more effective in the treatment of cuttings, reaching the extraction percentage of 87.04%, that is, obtaining a drill cuttings with 0.551% paraffin. Using the percentage of paraffin employed in non-aqueous drilling fluids and fluid maximum limit on cuttings for disposal established by the Environmental Protection Agency of the United States (US EPA), one arrives at the conclusion that the level of paraffin on gravel cannot exceed 3.93%. Conclude that the amount of paraffin in the treated cuttings with the microemulsion system with shaking is below the established by US EPA, showing that the system used was efficient in removing the paraffin from the drill cuttings.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-31T23:01:40Z No. of bitstreams: 1 RogerioPitangaSantos_DISSERT.pdf: 4092044 bytes, checksum: 81e41394327b3f461988b98662aa355f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-04T22:17:21Z (GMT) No. of bitstreams: 1 RogerioPitangaSantos_DISSERT.pdf: 4092044 bytes, checksum: 81e41394327b3f461988b98662aa355f (MD5) / Made available in DSpace on 2016-04-04T22:17:21Z (GMT). No. of bitstreams: 1 RogerioPitangaSantos_DISSERT.pdf: 4092044 bytes, checksum: 81e41394327b3f461988b98662aa355f (MD5) Previous issue date: 2015-06-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A utiliza??o de plantas com finalidades medicinais ? milenar, sendo bastante difundida sua aplica??o em medicamentos. Apesar das plantas serem fontes promissoras para a descoberta de novas mol?culas de interesse farmacol?gico, estimativas revelam que apenas 17% delas foram estudadas quanto a sua possibilidade de uso na medicina. Assim, a biodiversidade da flora brasileira representa um imenso potencial de utiliza??o econ?mica pela ind?stria farmac?utica. A planta Arrabidaea chica, popularmente conhecida como ?pariri?, ? comum na regi?o Amaz?nica, e a ela s?o atribu?das v?rias propriedades medicinais. As folhas desta planta s?o ricas em antocianinas, que s?o compostos fen?licos com alto poder antioxidante. Os compostos antioxidantes desempenham um papel vital na preven??o de doen?as neurol?gicas e cardiovasculares, c?ncer e diabetes, entre outras. Dentre as antocianinas encontradas na Arrabidaea chica, destaca-se a Carajurina (6,7-dihidroxi-5,4?- dimetoxi-flavilium), que ? o principal pigmento encontrado nesta planta. O presente trabalho teve como objetivo geral o estudo sobre a extra??o supercr?tica e a extra??o convencional (s?lido-l?quido) de folhas da Arrabidaea chica, avaliando-se o rendimento dos processos extrativos, a atividade antioxidante e a quantifica??o de Carajurina contida nos extratos. As extra??es supercr?ticas utilizaram CO2 como solvente, adicionado de co-solvente (mistura etanol/?gua), e foram conduzidas pelo m?todo din?mico em um extrator de leito fixo. Os ensaios obedeceram a um planejamento fatorial fracion?rio 24-1, tendo como vari?veis resposta o rendimento do processo, o poder antioxidante e a concentra??o de Carajurina, e como vari?veis independentes a press?o, a temperatura, a concentra??o de co-solvente (v/v) e a concentra??o de ?gua no co-solvente (v/v). Os rendimentos (massa de extrato seco/massa de mat?ria-prima utilizada) obtidos da extra??o supercr?tica variaram de 15,1% a 32%, sendo que o melhor resultado foi obtido a 250 bar e 40?C, com uso do co-solvente a 30% (v/v) e concentra??o de ?gua no co-solvente igual a 50% (v/v). Atrav?s de an?lise estat?stica, verificou-se que a concentra??o de co-solvente apresentou efeito significativo sobre o rendimento. Os resultados de rendimento em massa para as extra??es convencionais foram de 8,1% (?gua) e 5,5% (etanol). Atrav?s de an?lises cromatogr?ficas em CLAE (Cromatografia L?quida de Alta Efici?ncia), a Carajurina foi quantificada em todos os extratos obtidos e os valores de concentra??o (massa de Carajurina/massa de extrato seco) variaram entre 1% e 2,21% para os extratos supercr?ticos. Quanto ?s extra??es convencionais, n?o foi detectada Carajurina no extrato aquoso, enquanto o extrato etan?lico apresentou teor de Carajurina igual a 7,04%, sendo, portanto, mais seletivo em Carajurina do que as extra??es supercr?ticas. A avalia??o do poder antioxidante (m?todo do sequestro do radical 2,2-difenil-1-picril-hidrazilDPPH) dos extratos supercr?ticos resultou em valores de EC50 (concentra??o efetiva que neutraliza 50% dos radicais livres) compreendidos entre 38,34 e 86,13 ?g/mL, enquanto que as extra??es convencionais resultaram em valores de EC50 de 167,34 (?gua) e 42,58 (etanol) ?g/mL. J? a quantifica??o dos compostos fen?licos (m?todo espectrofotom?trico de FolinCiocalteau) dos extratos supercr?ticos resultou em valores compreendidos entre 48,93 e 88,62 mg EAG/g extrato (EAG = Equivalentes de ?cido G?lico), enquanto que as extra??es s?lidol?quido resultaram em valores de 37,63 (?gua) e 80,54 (etanol) mg EAG/g extrato. A boa atividade antioxidante pode ser atribu?da n?o somente ? presen?a de Carajurina, mas tamb?m ? exist?ncia de outros compostos fen?licos e antioxidantes na Arrabidaea chica. Atrav?s da otimiza??o do planejamento experimental, foi poss?vel identificar o experimento que apresentou o melhor resultado considerando as quatro vari?veis resposta em conjunto. Este experimento foi realizado nas seguintes condi??es: press?o de 200 bar, temperatura de 40?C, concentra??o de co-solvente igual a 30% (v/v) e concentra??o de ?gua no co-solvente igual a 30% (v/v). Conclui-se que, dentro da faixa estudada, ? poss?vel obter o resultado ?timo utilizando condi??es operacionais mais amenas, o que implica em menores custos e maior facilidade de opera??o. / The use of plants for medicinal purposes is ancient, with widespread application in medicinal drugs. Although plants are promising sources for the discovery of new molecules of pharmacological interest, estimates show that only 17% of them have been studied for their possible use in medicine. Thus, biodiversity of Brazilian flora represents an immense potential for economic use by the pharmaceutical industry. The plant Arrabidaea chica, popularly known as ?pariri?, is common in the Amazon region, and it is assigned several medicinal properties. The leaves of this plant are rich in anthocyanins, which are phenolic compounds with high antioxidant power. Antioxidant compounds play a vital role in the prevention of neurological and cardiovascular diseases, cancer and diabetes, among others. Within the anthocyanins found in Arrabidaea chica, stands out Carajurin (6,7-dihydroxy-5,4?- dimethoxy-flavilium), which is the major pigment encountered in this plant. The present work aimed to study on supercritical extraction and conventional extraction (solid-liquid extraction) in leaves of Arrabidaea chica, evaluating the efficiency of the extractive processes, antioxidant activity and quantification of Carajurin contained in the extracts. Supercritical extraction used CO2 as solvent with addition of co-solvent (ethanol/water mixture) and were conducted by the dynamic method in a fixed bed extractor. The trials followed a 24-1 fractional factorial design, the dependent variables were: process yield, concentration of Carajurin and antioxidant activity; and independent variables were: pressure, temperature, concentration of co-solvent (v/v) and concentration of water in the co-solvent mixture (v/v). Yields (mass of dry extract/mass of raw material used) obtained from supercritical extraction ranged from 15.1% to 32%, and the best result was obtained at 250 bar and 40 ?C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 50%. Through statistical analysis, it was found that the concentration of co-solvent revealed significant effect on the yield. Yields obtained from conventional extractions were of 8.1% (water) and 5.5% (ethanol). Through HPLC (High-performance liquid chromatography) analysis, Carajurin was quantified in all the extracts and concentration values (Carajurin mass/mass of dry extract) ranged between 1% and 2.21% for supercritical extraction. For conventional extraction, Carajurin was not detected in the aqueous extract, while the ethanol extract showed Carajurin content of 7.04%, and therefore, more selective in Carajurin than the supercritical extraction. Evaluation of antioxidant power (radical 2,2-diphenyl-1-picrylhydrazyl ? DPPH ? sequestration method) of the supercritical extracts resulted in EC50 values (effective concentration which neutralizes 50% of free radicals) ranged from 38.34 to 86.13 ?g/mL, while conventional extraction resulted in EC50 values of 167.34 (water) and 42.58 (ethanol) ?g/mL. As for the quantification of total phenolic content (Folin-Ciocalteau analysis) of the supercritical extracts resulted in values ranged from 48.93 and 88.62 mg GAE/g extract (GAE = Gallic Acid Equivalents), while solid-liquid extraction resulted in values of 37.63 (water) and 80.54 (ethanol) mg GAE/g extract. The good antioxidant activity cannot be attributed solely to the presence of Carajurin, but also the existence of other compounds and antioxidants in Arrabidaea chica. By optimizing the experimental design, it was possible to identify the experiment that presented the best result considering the four dependent variables together. This experiment was performed under the following conditions: pressure of 200 bar, temperature of 40 ?C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 30%. It is concluded that, within the studied range, it is possible to purchase the optimum result using milder operating conditions, which implies lower costs and greater ease of operation.

Made available in DSpace on 2014-12-17T15:01:16Z (GMT). No. of bitstreams: 1 DannielleJS.pdf: 1624896 bytes, checksum: 0e96250738f2bfbc525b251adc249965 (MD5) Previous issue date: 2008-12-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The decontamination of the materials has been subject of some studies. One of the factors that it increases the pollution is the lack of responsibility in the discarding of toxic trash, as for example the presence of PCB (Polychlorinated Biphenyls) in the environment. In the Brazilian regulations, the material contaminated with PCB in concentrations higher than 50 ppm must be stored in special places or destroyed, usually by incineration in plasma furnace with dual steps. Due to high cost of the procedure, new methodologies of PCBs removal has been studied. The objective of this study was to develop an experimental methodology and analytical methodology for quantification of removal of PCBs through out the processes of extractions using supercritical fluid and Soxhlet method, also technical efficiency of the two processes of extraction, in the treatment of contaminated materials with PCBs. The materials studied were soils and wood, both were simulated contamination with concentration of 6.000, 33.000 and 60.000 mg of PCB/ kg of materials. Soxhlet extractions were performed using 100 ml of hexane, and temperature of 180 ?C. Extractions by fluid supercritical were performed at conditions of 200 bar, 70?C, and supercritical CO2 flow-rate of 3 g/min for 1-3 hours. The extracts obtained were quantified using Gas chromatography-mass spectrometry (GC/MS). The conventional extractions were made according to factorial experimental planning technique 22, with aim of study the influence of two variables of process extraction for the Soxhlet method: contaminant concentration and extraction time for obtain a maximum removal of PCB in the materials. The extractions for Soxhlet method were efficient for extraction of PCBs in soil and wood in both solvent studied (hexane and ethanol). In the experimental extraction in soils, the better efficient of removal of PCBs using ethanol as solvent was 81.3% than 95% for the extraction using hexane as solvent, for equal time of extraction. The results of the extraction with wood showed statistically it that there is not difference between the extractions in both solvent studied. The supercritical fluid extraction in the conditions studied showed better efficiency in the extraction of PCBs in the wood matrix than in soil, for two hours extractions the obtain percentual of 43.9 ? 0.5 % for the total of PCBs extracted in the soils against 95.1 ? 0,5% for the total of PCBs extracted in the wood. The results demonstrated that the extractions were satisfactory for both technical studied / A descontamina??o de materiais tem sido tema de v?rios estudos. Um dos fatores que aumenta a polui??o ? a falta de responsabilidade no descarte do lixo t?xico, como por exemplo, a presen?a de PCBs (Bifenilas policloradas) no meio ambiente. Nos regulamentos brasileiros, o material contaminado com PCBs nas concentra??es acima de 50 ppm deve ser armazenado em lugares especiais ou ser destru?do, geralmente por incinera??o em forno de plasma com duplo est?gio. Devido ao custo elevado deste processo, novas metodologias para remo??o de PCBs est?o sendo pesquisadas. O objetivo deste estudo foi desenvolver uma metodologia experimental e anal?tica para a quantifica??o da remo??o de PCBs de materiais contaminados atrav?s de extra??o pelo m?todo Soxhlet e por flu?do supercr?tico, como tamb?m avaliar e comparar a efici?ncia t?cnica dos dois processos de extra??o. Os materiais avaliados foram: solo e madeira ambos contaminados com PCBs via contamina??o simulada. Os materiais foram contaminados com a concentra??o de 6.000, 33.000 e 60.000 mg de ?leo Ascarel/ kg de material. A extra??o pelo m?todo Soxhlet foi realizada usando 100 mL de solvente org?nico (hexano ou etanol), 180 ?C e press?o atmosf?rica. A extra??o com flu?do supercr?tico foi realizada nas seguintes condi??es: 200 bar, 70 ?C e 3 g de CO2 / min. Os extratos obtidos foram quantificados usando a cromatografia gasosa acoplada a um espectr?metro de massa (CG-EM). Foram realizadas extra??es pelo m?todo convencional usando a t?cnica de planejamento fatorial 22, com a finalidade de estudar os efeitos da concentra??o inicial de contaminante e o tempo de extra??o no percentual de remo??o de PCBs. As extra??es pelo m?todo Soxhlet foi eficiente para extra??o de PCBs em solo e em madeira para os dois solventes em estudo (hexano e etanol). Nos experimentos de extra??o em solos, o melhor percentual de remo??o de PCBs usando etanol como solvente foi de 81,3% e 95% para a extra??o que usa hexano como solvente, com o mesmo tempo de extra??o. Os resultados dos ensaios de extra??o com madeira, mostraram que estatisticamente n?o h? diferen?a entre as extra??es mudando o solvente. A extra??o por fluido supercr?tico nas condi??es estudadas teve melhor desempenho para extrair PCBs na matriz madeira do que no solo. Em duas horas de extra??o foi obtido percentual de 43,9 ? 0,5 % para a soma do total de PCBs extra?do no solo contra 95,1 ? 0,5 % para a soma total de PCBs extra?do na madeira. Os resultados foram satisfat?rios para ambas as t?cnicas de extra??o estudadas

Made available in DSpace on 2014-12-17T15:01:46Z (GMT). No. of bitstreams: 1 DulcineiaCS.pdf: 1697403 bytes, checksum: 0f7cd236e54bc771afdfff455ddc2e54 (MD5) Previous issue date: 2008-07-25 / The study of a promising alternative for the treatment of produced water from the oil industry envisaging its reuse was the focus of this work. Millions of liters of water are generated per day, containing heavy metals in low concentrations (< 0,15 mg/L for Pb, <0,04 mg/L for Cd, <0,04 mg/L for Ni). The technology applied to extract these metals from aqueous phase was the solvent extraction and the extratants used were vegetable oils originated from coconut oil. They can be used in natural form or as derivatives, known as MAC - Mixture of Carbox?lics Acids. The determination of the heavy metal con?centrations in a complex matrix was made by using the atomic absorption spectrometry technique (AAS). On the bench tests using synthetics aqueous solutions containing metals, vegetable oils showed no power to extract the metals studied. The extractant MAC was selective for the Pb> Cd> Ni, in the concentration of 8% in the same organic phase. In this condition, the lower efficiency of extraction obtained was 92% for the Pb, 69% for the Cd, in the range of pH ranging from 6 to 8. An experimental planning was conducted for continuous tests. The device used was called MDIF Misturador-Decantador ? Invers?o de Fases and the aqueous phase was produced water from P?lo Indutrial de Guamar?/RN . No correlation between the studied variables (concentration of metal, concentration of extratant and agitation in the mixing chamer) could be obtained, because of possible factors which occurred as: variation in the composition of the studied sample, phenomena of precipitation and complexation of metals in the reservoir of feed, solubility of extratant / O estudo de uma promissora alternativa para o tratamento de ?guas produzidas da ind?stria do petr?leo visando a sua reutiliza??o foi o foco deste trabalho. S?o milh?es de litros de ?gua/dia descartados ao mar, atrav?s de emiss?rios submarinos, contendo metais pesados em baixas concentra??es (< 0,15 mg/L de Pb, <0,04 mg/L de Cd, <0,04 mg/L de Ni). A tecnologia utilizada para extrair esses metais da fase aquosa foi a extra??o por solvente e os extratantes estudados foram ?leos vegetais in natura e derivados do ?leo de coco, denominada MAC Mistura de ?cidos Carbox?licos. A determina??o da concentra??o dos metais pesados em matriz complexa foi realizada utilizando o EAA Espectr?metro de Absor??o At?mica. Nos ensaios de bancada realizados, com solu??es sint?ticas contendo metais, os ?leos vegetais n?o apresentaram poder de extra??o dos metais estudados. J? o extratante MAC foi seletivo para o Pb > Cd > Ni na concentra??o de 8% do mesmo na fase org?nica. Nesta condi??o, a menor efici?ncia de extra??o obtida foi de 92% para o Pb, 69% para o Cd, na faixa de pH variando de 6 a 8. Um planejamento experimental foi realizado para os ensaios em regime cont?nuo. O equipamento utilizado foi o MDIF - Misturador Decantador ? Invers?o de Fases e a fase aquosa utilizada foi a ?gua produzida proveniente da sa?da do SAO Separador ?gua ?leo do P?lo Industrial de Guamar?/RN. Nenhuma correla??o entre as vari?veis estudadas, concentra??o do metal, concentra??o do extratante e agita??o na c?mara de mistura pode ser obtida devido a poss?veis fatores ocorridos como: varia??o na composi??o da amostra estudada, fen?menos de precipita??o e complexa??o de metais no reservat?rio de alimenta??o, solubiliza??o do extratante