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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.
31

An?lise mec?nica da resist?ncia da fixa??o na osteotomia sagital do ramo ap?s diferentes movimentos de avan?o mandibular: estudo in vitro

Assis, Gleysson Matias de 10 February 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T23:22:20Z No. of bitstreams: 1 GleyssonMatiasDeAssis_DISSERT.pdf: 1359858 bytes, checksum: fe9b88f922668d56c2a5d194da819485 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-12T00:40:00Z (GMT) No. of bitstreams: 1 GleyssonMatiasDeAssis_DISSERT.pdf: 1359858 bytes, checksum: fe9b88f922668d56c2a5d194da819485 (MD5) / Made available in DSpace on 2017-04-12T00:40:00Z (GMT). No. of bitstreams: 1 GleyssonMatiasDeAssis_DISSERT.pdf: 1359858 bytes, checksum: fe9b88f922668d56c2a5d194da819485 (MD5) Previous issue date: 2017-02-10 / O objetivo deste trabalho foi de avaliar, atrav?s de um ensaio mec?nico, a resist?ncia da fixa??o na osteotomia sagital do ramo mandibular (OSRM) em tr?s diferentes movimentos de avan?o mandibular, bem como a influ?ncia do movimento associado a rota??o hor?rio do plano mandibular, utilizando miniplacas (4 e 6 elos) e parafusos com 6 mm de comprimento, do sistema 2.0 mm (Egimplan? ). Dois tipos de avan?os foram empregados (6 e 12 mm), utilizando hemimand?bulas de poliuretano com OSRM padronizadas de f?brica, divididos em 5 grupos: G1(Teste 1) - avan?o linear de 6 mm/ 1 placa e 4 parafusos; G2 (Teste 2) - avan?o linear de 12 mm/1 placa e 4 parafusos; G3 (Teste 3)- avan?o linear de 12 mm /2 placas e 8 parafusos; G4 (Teste 4) - avan?o de 12 mm, associado a rota??o hor?ria do plano mandibular(15?) / 1 placa e 4 parafusos; G5 (Teste 5) - avan?o de 12 mm, associado a rota??o hor?rio do plano mandibular(15?)/2 placas e 8 parafusos. As hemimand?bulas foram submetidas a uma carga compressiva vertical na regi?o de primeiro molar e a for?a aplicada, em Newtons, foi registrada nos deslocamentos de 1mm, 5 mm e 10 mm, como tamb?m a for?a m?xima aplicada entre 1 e 10 mm. Utilizando um intervalo de confian?a de 95%, as m?dias de for?a foram obtidas e os grupos foram comparados entre si. Os testes estat?sticos utilizados foram o Kruskal-Wallis* para a an?lise de todos os grupos e o de Mann-Whitney** para o comparativo de dois grupos em separado. Os resultados mostraram que o grupo G3 apresentou m?dias de for?a maiores (p < 0,001*), sendo, portanto, o mais resistente entre os grupos. Quando foi utilizado apenas 1 placa para a fixa??o da hemimandibula, no avan?o de 12 mm, a realiza??o da rota??o hor?ria foi mais resistente do que no movimento linear, nos deslocamentos de 1, 5 e 10 mm (p< 0,05**), n?o resultando em diferen?a estat?stica apenas no deslocamento m?ximo (p= 0,112**). Em um grande avan?o (12mm) houve uma perda de resist?ncia importante na fixa??o, sendo necess?rio compensar essa situa??o com uso de mais fixa??o e a rota??o hor?rio nesses casos tamb?m acrescentaram resist?ncia na OSRM, apenas nos casos em que se utiliza uma ?nica placa. / The objective of this study was to evaluate by means of mechanical testing the fixation strength in sagittal split ramus osteotomy (SSRO) for three different movements of mandibular advancement, as well as the influence of movement associated with clockwise rotation of the mandibular plane, using miniplates (4 and 6 holes) and 6-mm screws of the 2.0 mm system (Engimplan?). Two types of advancement were employed (6 and 12 mm) using polyurethane hemimandibles with factory-standardized SSO, divided into five groups: G1 (test 1) ? linear advancement of 6 mm/1 plate and 4 screws; G2 (test 2) ? linear advancement of 12 mm/1 plate and 4 screws; G3 (test 3) ? linear advancement of 12 mm/2 plates and 8 screws; G4 (test 4) ? advancement of 12 mm associated with clockwise rotation of the mandibular plane (15?)/1 plate and 4 screws; G5 (test 5) ? advancement of 12 mm associated with clockwise rotation of the mandibular plane (15?)/2 plates and 8 screws. The hemimandibles were submitted to a vertical compressive load in the region of the first molar and the force applied (in Newton) was recorded for displacements of 1, 5 and 10 mm, as was the maximum force applied between 1 and 10 mm. Using a 95% confidence interval, the mean force values were obtained and compared between groups. The Kruskal-Wallis* test was used for analysis of all groups and the Mann-Whitney** test for the comparison of two groups. The results showed higher mean force values for G3 (p < 0.001*), which was therefore the treatment that provided the greatest strength. When only 1 plate was used for fixation of the hemimandible, in the advancement of 12 mm, clockwise rotation resulted in a greater fixation strength than the linear movement for displacements of 1, 5 and 10 mm (p < 0.05**), with no significant difference being observed only for the maximum displacement (p = 0.112**). Important loss of strength in fixation was observed for the large advancement (12 mm) and it was necessary to compensate this situation with the use of more fixation. Clockwise rotation added strength to the SSO only in cases in which a single plate was used.
32

Influ?ncia da altera??o do plano oclusal: magnitude do movimento e tipo de osteoss?ntese na resist?ncia mec?nica da fixa??o na osteotomia sagital do ramo mandibular: estudo in vitro

Santos, Victor Diniz Borborema dos 19 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-05T00:11:27Z No. of bitstreams: 1 VictorDinizBorboremaDosSantos_DISSERT.pdf: 2006909 bytes, checksum: bac53377cdf34bb2c1b4d10fc273d846 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-16T21:50:04Z (GMT) No. of bitstreams: 1 VictorDinizBorboremaDosSantos_DISSERT.pdf: 2006909 bytes, checksum: bac53377cdf34bb2c1b4d10fc273d846 (MD5) / Made available in DSpace on 2017-10-16T21:50:04Z (GMT). No. of bitstreams: 1 VictorDinizBorboremaDosSantos_DISSERT.pdf: 2006909 bytes, checksum: bac53377cdf34bb2c1b4d10fc273d846 (MD5) Previous issue date: 2017-07-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O objetivo deste trabalho foi avaliar, atrav?s de um ensaio biomec?nico a resist?ncia da fixa??o na osteotomia sagital do ramo mandibular (OSRM) em dois tipos de avan?os (6 e 12 mm), associados ou n?o a rota??o do plano oclusal, utilizando placas e parafusos do sistema 2.0 mm. Foram utilizadas hemimand?bulas de poliuretano, com OSRM padronizadas, divididos em 7 grupos: Avan?o linear de 6 mm / 1 placa e 4 parafusos (G1); avan?o linear de 12 mm/1 placa e 4 parafusos (G2); avan?o linear de 12 mm /2 placas e 8 parafusos (G3); avan?o de 12 mm, associado a rota??o hor?ria do plano oclusal / 1 placa e 4 parafusos (G4); avan?o de 12 mm, associado a rota??o hor?rio do plano oclusal/2 placas e 8 parafusos (G5); avan?o de 12 mm, associado ao giro anti-hor?rio do plano oclusal / 1 placa e 4 parafusos (G6); - avan?o de 12 mm, associado ao giro anti-hor?rio do plano oclusal/2 placas e 8 parafusos (G7). As hemimand?bulas foram submetidas a uma carga compressiva vertical na regi?o de primeiro molar e a for?a aplicada, em Newtons, foi registrada nos deslocamentos de 1mm, 5 mm e 10 mm, bem como tamb?m a for?a m?xima. Utilizando um intervalo de confian?a de 95%, as medianas de for?a foram obtidas e os grupos foram comparados entre si. Os testes estat?sticos utilizados foram o Kruskal-Wallis* para a an?lise de todos os grupos e o de Mann-Whitney** para o comparativo de dois grupos separadamente. Os resultados mostraram que, segundo o teste de Kruskall-Wallis houve diferen?as entre os grupos. Ficou demonstrado que o aumento da magnitude do avan?o mandibular diminuiu a resist?ncia da osteoss?ntese na OSRM quando se utilizou um ?nico dispositivo de fixa??o. A inser??o de uma placa adicional em grandes avan?os (G3, G5 e G7), aumentou significativamente a resist?ncia do m?todo de osteoss?ntese de uma maneira geral, quando comparada aos demais grupos. Em grandes avan?os com modifica??o do plano oclusal fixados com uma ?nica placa (G4 e G6), houve um aumento significativo da resist?ncia da fixa??o apenas no movimento de rota??o hor?ria. A rota??o anti-hor?ria do plano oclusal foi significativamente mais resistente que a hor?ria, quando se utilizou 2 placas na estabiliza??o da OSRM. / The aim of this study was to evaluate the resistance of fixation in the sagittal osteotomy of the mandibular ramus (OSRM) when performing great advances (12 mm), as well as the influence of the movement associated with the anticlockwise/clockwise rotation of the occlusal plane , Using plates and screws of the 2.0 mm system. Two types of advances were used (6 and 12 mm) using polyurethane hemimandibulars, with standardized OSRM, divided into 7 groups: G1 - linear advance of 6 mm / 1 plate and 4 screws; G2 - linear advance of 12 mm / 1 plate and 4 screws; G3 - linear advance of 12 mm / 2 plates and 8 screws; G4 - 12 mm advance, associated with clockwise rotation of the occlusal plane (15 ?) / 1 plate and 4 screws; G5 - 12 mm advance, associated with clockwise rotation of the occlusal plane (15 ?) / 2 plates and 8 screws; G6 - 12 mm advance, associated with anticlockwise rotation of the occlusal plane (15 ?) / 1 plate and 4 screws; G7 - 12 mm advance, associated with the counterclockwise rotation of the plane (15 ?) / 2 plates and 8 screws. The hemimandibules were submitted to a vertical compressive load in the first molar region and the applied force in Newtons was recorded in the displacements of 1mm, 5mm and 10mm, as well as the maximum force applied between 1 and 10mm. Using a 95% confidence interval, the means of strength were obtained and the groups were compared to each other. The statistical tests used were Kruskal-Wallis for the analysis of all groups and the Mann-Whitney test for comparison of two groups separately. The results showed that, according to the Kruskall-Wallis test, there were differences between groups. When only 1 plate was used for the fixation of the hemimandibula, at the 12 mm advance, the clockwise rotation was more resistant than in the linear movement, at the displacements of 1, 5 and 10 mm (p <0.05 **), Not resulting in statistical difference only in the maximum displacement (p = 0.112 **). In a large advance (12mm) there was a significant loss of resistance in the FIR, being necessary to compensate this situation with use of more fixation and the clockwise/counterclockwise rotation in these cases also added resistance in the OSRM, only in cases where a single plate is used. The counter-clockwise turn proved to be less sturdy than the clockwise rotation when fixed with one plate and more resistant when fixed with 2 plates. Both situations presented statistical significance with p <0.05. In view of these findings, it was concluded that regardless of movement, the fixation with 2 plates considerably increases the resistance to applied force.
33

Sistema microemulsionado: caracteriza??o e aplica??o na ind?stria de petr?leo

Silva, Guymmann Clay da 12 August 2011 (has links)
Made available in DSpace on 2014-12-17T15:42:14Z (GMT). No. of bitstreams: 1 GuymmannCS_DISSERT-.pdf: 2904070 bytes, checksum: 4cd1c00978977c422c79766db70f2678 (MD5) Previous issue date: 2011-08-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Alkyl polyethoxylates are surfactants widely used in vastly different fields, from oil exploitation to pharmaceutical applications. One of the most interesting characteristics of these surfactants is their ability to form micellar systems with specific geometry, the so-called wormlike micelle. In this work, microemulsions with three distinct compositions (C/T = 40 %, 30 % and 25 %) was used with contain UNITOL / butanol / water / xylene, cosurfactant / surfactante (C/S) ratio equal to 0,5. The microemulsion was characterized by dynamic light scattering (DLS), capillary viscometry, torque rheometry and surface tensiometry experiments carried out with systems based on xylene, water, butanol (cosurfactant) and nonaethyleneglycolmonododecyl ether (surfactant), with fixed surfactant:cosurfactant:oil composition (with and without oil phase) and varying the overall concentration of the microemulsion. The results showed that a transition from wormlike micelles to nanodrops was characterized by maximum relative viscosity (depending on how relative viscosity was defined), which was connected to maximum effective diameter, determined by DLS. Surface tension suggested that adsorption at the air water interface had a Langmuir character and that the limiting value of the surfactant surface excess was independent of the presence of cosurfactant and xylene. The results of the solubilization of oil sludge and oil recovery with the microemulsion: C/S = 40%, 30% and 25% proved to be quite effective in solubilization of oil sludge, with the percentage of solubilization (%solubilization) as high as 92.37% and enhanced oil recovery rates up to 90.22% for the point with the highest concentration of active material (surfactant), that is, 40%. / Os tensoativos alquil-polietoxilados s?o amplamente utilizados em diferentes campos, desde a explota??o de petr?leo at? aplica??es na ind?stria farmac?utica. Uma das caracter?sticas mais interessantes destes tensoativos ? a sua capacidade de formar sistemas micelares que apresentam uma geometria micelar espec?fica, a chamada micela wormlike, tipo verme . Neste trabalho, foram utilizados tr?s pontos de microemuls?o: C/T = 40 %, C/T = 30 % e C/T = 25 % num sistema contendo UNITOL/xileno/butanol/?gua. Esses pontos de microemuls?o foram caracterizados por espalhamento de luz din?mico (DLS), viscosimetria capilar, reometria de torque e tens?o superficial com composi??es de tensoativo, cotensoativo e ?leo fixo - 5 % (com e sem fase ?leo) e variando a concentra??o total dos pontos de microemuls?o. Os resultados mostraram que a transi??o da geometria de micela wormlike para nanogotas poderia ser caracterizada por um m?ximo na viscosidade relativa (dependendo de como a viscosidade foi definida), que foi vinculado a um m?ximo de di?metro efetivo, determinada por DLS. A tens?o superficial sugeriu que a adsor??o na interface ?gua/ar tinha um car?ter de Langmuir, o limite de excesso da superf?cie do tensoativo ? independente da presen?a de cotensoativo e do xileno, e que o valor limite do excesso superficial foi independente da presen?a de cotensoativo e xileno. Os resultados da solubiliza??o da borra de petr?leo e da recupera??o avan?ada de petr?leo com os pontos de microemuls?o C/T = 40 %, C/T = 30 % e C/T = 25 %, se mostraram bastante eficaz com solubiliza??o da borra de petr?leo, com porcentagem de solubiliza??o (% solubiliza??o) at? 92,37 %, e recupera??o avan?ada de petr?leo de at? 90,22 % para o ponto que apresenta maior concentra??o de mat?ria ativa (tensoativo), ou seja, C/T = 40 %.
34

Uma an?lise hist?rico-epistemol?gica do conceito de grupo

Quaresma, Jo?o Cl?udio Brandemberg 19 February 2009 (has links)
Made available in DSpace on 2014-12-17T14:36:01Z (GMT). No. of bitstreams: 1 JoaoCBQ.pdf: 1363815 bytes, checksum: 1e07e6a070ddb0ed8acc6e7cea8e04c5 (MD5) Previous issue date: 2009-02-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to analyze the historical and epistemological development of the Group concept related to the theory on advanced mathematical thinking proposed by Dreyfus (1991). Thus it presents pedagogical resources that enable learning and teaching of algebraic structures as well as propose greater meaning of this concept in mathematical graduation programs. This study also proposes an answer to the following question: in what way a teaching approach that is centered in the Theory of Numbers and Theory of Equations is a model for the teaching of the concept of Group? To answer this question a historical reconstruction of the development of this concept is done on relating Lagrange to Cayley. This is done considering Foucault s (2007) knowledge archeology proposal theoretically reinforced by Dreyfus (1991). An exploratory research was performed in Mathematic graduation courses in Universidade Federal do Par? (UFPA) and Universidade Federal do Rio Grande do Norte (UFRN). The research aimed to evaluate the formation of concept images of the students in two algebra courses based on a traditional teaching model. Another experience was realized in algebra at UFPA and it involved historical components (MENDES, 2001a; 2001b; 2006b), the development of multiple representations (DREYFUS, 1991) as well as the formation of concept images (VINNER, 1991). The efficiency of this approach related to the extent of learning was evaluated, aiming to acknowledge the conceptual image established in student s minds. At the end, a classification based on Dreyfus (1991) was done relating the historical periods of the historical and epistemological development of group concepts in the process of representation, generalization, synthesis, and abstraction, proposed here for the teaching of algebra in Mathematics graduation course / O presente estudo analisa o desenvolvimento hist?rico-epistemol?gico do conceito de Grupo a luz da teoria do pensamento matem?tico avan?ado, proposto por Dreyfus (1991) e apresenta subs?dios did?ticos que contribuam para o ensino-aprendizagem das estruturas alg?bricas, visando dar maior significado ao referido conceito abordado na gradua??o em Matem?tica. Nesse sentido, o estudo responde a seguinte pergunta: de que maneira uma abordagem de ensino, inicialmente, centrada na Teoria dos N?meros e na Teoria das Equa??es se constituiria em um modelo de efetiva??o do ensino do conceito de Grupo? Para responder a quest?o fizemos uma reconstru??o hist?rica do desenvolvimento desse conceito, de Lagrange a Cayley, em uma reescrita orientada na arqueologia do saber proposta e discutida por Foucault (2007) e com o apoio te?rico em Dreyfus (1991) analisamos o material hist?rico elaborado. Em seguida, fizemos uma pesquisa explorat?ria com turmas da gradua??o em Matem?tica da Universidade Federal do Par? (UFPA) e da Universidade Federal do Rio Grande do Norte (UFRN), para avaliar a forma??o de imagens conceituais nos alunos participantes de dois cursos de ?lgebra baseado em um modelo tradicional de ensino. Al?m disso, realizamos outra experi?ncia, na UFPA, com o ensino de ?lgebra envolvendo, conjuntamente, a inclus?o da componente hist?rica (MENDES, 2001a; 2001b; 2006b), o desenvolvimento de m?ltiplas representa??es (DREYFUS, 1991) e a forma??o das imagens conceituais (VINNER, 1991). Avaliamos a efic?cia da abordagem em termos da profundidade no alcance do aprendizado, ou seja, a imagem conceitual estabelecida na mente dos alunos. Ao final, apresentamos uma classifica??o, baseada em Dreyfus (1991), que relaciona per?odos hist?ricos do desenvolvimento hist?rico-epistemol?gico do conceito de grupo aos processos de representa??o, generaliza??o, s?ntese e abstra??o, e uma proposta para um curso de ?lgebra na gradua??o em Matem?tica
35

Recupera??o avan?ada de ?leos pesados em po?os fraturados utilizando aquecimento eletromagn?tico indutivo

Ara?jo J?nior, Aldayr Dantas de 29 April 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-22T19:35:00Z No. of bitstreams: 1 AldayrDantasDeAraujoJunior_TESE.pdf: 6801282 bytes, checksum: 6465e3e1ed3f877f913f31049263ffc2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-28T19:14:32Z (GMT) No. of bitstreams: 1 AldayrDantasDeAraujoJunior_TESE.pdf: 6801282 bytes, checksum: 6465e3e1ed3f877f913f31049263ffc2 (MD5) / Made available in DSpace on 2016-03-28T19:14:32Z (GMT). No. of bitstreams: 1 AldayrDantasDeAraujoJunior_TESE.pdf: 6801282 bytes, checksum: 6465e3e1ed3f877f913f31049263ffc2 (MD5) Previous issue date: 2015-04-29 / O ?xito atingido pelos m?todos t?rmicos de recupera??o, em ?leos pesados, motivou o surgimento de estudos relacionados com a utiliza??o de ondas eletromagn?ticas como fontes geradoras de calor em reservat?rios de petr?leo. Desta maneira, essa gera??o ? obtida atrav?s de tr?s tipos de processos distintos de acordo com o intervalo de frequ?ncias utilizado. S?o eles: o aquecimento eletromagn?tico indutivo, o resistivo e o diel?trico, tamb?m conhecido como por radia??o. O presente estudo foi baseado em simula??es computacionais em reservat?rios de petr?leo com caracter?sticas similares aos encontrados nas bacias sedimentares do Nordeste brasileiro. Todos os casos estudados foram simulados usando o programa STARS, da CMG (Computer Group, Modelagem vers?o 2012.10). Algumas simula??es levaram em considera??o a inser??o de part?culas eletricamente sens?veis em determinados setores do modelo de reservat?rio estudado atrav?s de fraturas. A proposta deste trabalho ? a utiliza??o do aquecimento eletromagn?tico por indu??o como m?todo de recupera??o de ?leos pesados, para verificar a influ?ncia dessas part?culas acima citadas no modelo de reservat?rio utilizado. Foram feitas an?lises comparativas envolvendo o aquecimento eletromagn?tico indutivo, a opera??o do fraturamento hidr?ulico e a inje??o de ?gua em diferentes situa??es do modelo de reservat?rio estudado. Foi constatado que fraturando o po?o injetor com o intuito de que o aquecimento eletromagn?tico ocorra no mesmo po?o em que h? a inje??o de ?gua, houve um acr?scimo consider?vel do fator de recupera??o e produ??o acumulada de ?leo em rela??o aos modelos em que o fraturamento hidr?ulico ocorria no po?o produtor e a inje??o de ?gua no po?o injetor. Este fato se deve ? gera??o de vapor in situ no reservat?rio. / The success achieved by thermal methods of recovery, in heavy oils, prompted the emergence of studies on the use of electromagnetic waves as heat generating sources in oil reservoirs. Thus, this generation is achieved by three types of different processes according to the frequency range used. They are: the electromagnetic induction heating, the resistive and the dielectric, also known as radiation. This study was based on computer simulations in oil reservoirs with characteristics similar to those found in the sedimentary basins of the Brazilian Northeast. All cases studied were simulated using the software STARS, CMG (Computer Group, version 2012.10 Modeling). Some simulations took into account the inclusion of electrically sensitive particles in certain sectors of the reservoir model studied by fracturing. The purpose of this work is the use of the electromagnetic induction heating as a recovery method of heavy oil, to check the influence of these aforementioned particles on the reservoir model used. Comparative analyses were made involving electromagnetic induction heating, the operation of hydraulic fracturing and the injection of water to the different situations of the reservoir model studied. It was found that fracturing the injection well in order that the electromagnetic heating occurs in the same well where there is water injection, there was a considerable increase in the recovery factor and in the cumulative oil production in relation to the models in which hydraulic fracturing occurred in the production well and water injection in the injection well. This is due to the generation of steam in situ in the reservoir.
36

Desenvolvimento de um reator fotoqu?mico aplic?vel no tratamento de efluentes fen?licos presentes na ind?stria do petr?leo / Development of a photochemistry reactor applicable in the treatment of phenolic wastewaters present in the petroleum industry

Mota, Andr? Lu?s Novais 02 December 2005 (has links)
Made available in DSpace on 2014-12-17T15:01:16Z (GMT). No. of bitstreams: 1 AndreLNM.pdf: 781178 bytes, checksum: d7b742a561481a98abbefe98cb97f8fb (MD5) Previous issue date: 2005-12-02 / With water pollution increment at the last years, so many progresses in researches about treatment of contaminated waters have been developed. In wastewaters containing highly toxic organic compounds, which the biological treatment cannot be applied, the Advanced Oxidation Processes (AOP) is an alternative for degradation of nonbiodegradable and toxic organic substances, because theses processes are generation of hydroxyl radical based on, a highly reactivate substance, with ability to degradate practically all classes of organic compounds. In general, the AOP request use of special ultraviolet (UV) lamps into the reactors. These lamps present a high electric power demand, consisting one of the largest problems for the application of these processes in industrial scale. This work involves the development of a new photochemistry reactor composed of 12 low cost black light fluorescent lamps (SYLVANIA, black light, 40 W) as UV radiation source. The studied process was the photo-Fenton system, a combination of ferrous ions, hydrogen peroxide, and UV radiation, it has been employed for the degradation of a synthetic wastewater containing phenol as pollutant model, one of the main pollutants in the petroleum industry. Preliminary experiments were carrier on to estimate operational conditions of the reactor, besides the effects of the intensity of radiation source and lamp distribution into the reactor. Samples were collected during the experiments and analyzed for determining to dissolved organic carbon (DOC) content, using a TOC analyzer Shimadzu 5000A. The High Performance Liquid Chromatography (HPLC) was also used for identification of the cathecol and hydroquinone formed during the degradation process of the phenol. The actinometry indicated 9,06&#8901;1018 foton&#8901;s-1 of photons flow, for 12 actived lamps. A factorial experimental design was elaborated which it was possible to evaluate the influence of the reactants concentration (Fe2+ and H2O2) and to determine the most favorable experimental conditions ([Fe2+] = 1,6 mM and [H2O2] = 150,5 mM). It was verified the increase of ferrous ions concentration is favorable to process until reaching a limit when the increase of ferrous ions presents a negative effect. The H2O2 exhibited a positive effect, however, in high concentrations, reaching a maximum ratio degradation. The mathematical modeling of the process was accomplished using the artificial neural network technique / Com o crescente aumento da polui??o das ?guas acorrido nos ?ltimos anos, houve tamb?m um grande avan?o das pesquisas relacionadas ao tratamento de ?guas contaminadas. Efluentes contendo compostos org?nicos de alta toxicidade, nos quais o tratamento biol?gico n?o pode ser aplicado, os chamados processos oxidativos avan?ados (POA) surgem como uma alternativa para a degrada??o de subst?ncias org?nicas t?xicas n?o biodegrad?veis, pois estes processos s?o baseados na gera??o de radicais hidroxila, subst?ncias altamente reativas, capazes de degradar praticamente todas as classes de compostos org?nicos. Os POA, por muitas vezes, requerem o uso de reatores com l?mpadas especiais que emitem luz ultravioleta. Estas l?mpadas apresentam uma alta demanda de energia el?trica, consistindo, portanto, em um dos maiores problemas para a aplica??o desses processos em escala industrial. Este trabalho envolveu o desenvolvimento de um novo reator fotoqu?mico composto de 12 l?mpadas fluorescentes de luz negra de baixo custo como fonte de radia??o UV. O processo estudado foi o sistema foto-Fenton, uma combina??o de ?ons ferrosos, per?xido de hidrog?nio e radia??o ultravioleta, sendo aplicado na degrada??o de um efluente sint?tico aquoso contendo fenol, um dos principais poluentes da ind?stria do petr?leo. Foram realizados experimentos preliminares visando avaliar as condi??es operacionais do reator, al?m dos efeitos da intensidade da fonte de radia??o e distribui??o das l?mpadas no reator. As amostras foram analisadas quanto ao teor de carbono org?nico dissolvido (COD) utilizando um TOC 5000A da Shimadzu. A partir do recurso da cromatografia l?quida de alto desempenho (HPLC), p?de ser identificado a forma??o do catecol e da hidroquinona durante o processo de degrada??o do fenol. Pelo emprego da actinometria foi obtida uma taxa de incid?ncia de f?tons de 9,06&#8901;1018 foton&#8901;s-1, para 12 l?mpadas acionadas. Foi elaborado um planejamento fatorial ampliado do qual foi poss?vel avaliar a influ?ncia da concentra??o dos reagentes (Fe2+ e H2O2), al?m de ter sido determinado as condi??es ?timas experimentais ([Fe2+] = 1,6 mM e [H2O2] = 150,5 mM), obtendo um percentual m?ximo de degrada??o de 81,38 % em 1 hora de rea??o. Foi verificado que o aumento da concentra??o dos ?ons ferrosos ? favor?vel ao processo at? atingir um limite, quando o acr?scimo de ?ons ferrosos come?ou a apresentar um efeito negativo. O H2O2 apresentou um efeito positivo ao processo, atingindo um percentual m?ximo de degrada??o. A modelagem matem?tica do processo foi realizada utilizando o recurso da rede neural artificial, a qual p?de representar o sistema e o comportamento das vari?veis do processo

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