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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.
361

Especificação, instanciação e experimentação de um arcabouço para criação automática de ligações hipertexto entre informações homogêneas / Specification, instantion and experimentation of a framework intended to support the task of automatic creation of hypertext links between homogeneous repositories

Macedo, Alessandra Alaniz 02 July 2004 (has links)
Com a evolução da informática, diferentes meios de comunicação passaram a explorar a Web como um meio de divulgação de suas informações. Diferentes fontes de informações, diferentes estilos de escrita e a curiosidade nata do ser humano despertam o interesse de leitores por conhecer mais de um relato sobre um mesmo tema. Para que a leitura de diferentes relatos com conteúdo similar seja possível, leitores precisam procurar, ler e analisar informações fornecidas por diferentes fontes de informação. Essa atividade, além de exigir grande investimento de tempo, sobrecarrega cognitivamente usuários. Faz parte das pesquisas da área de Hipermídia investigar mecanismos que apóiem usuários no processo de identificação de informações em repositórios homogêneos, sejam eles disponibilizados na Web ou não. No contexto desta tese, repositórios com informações de conteúdo homogêneo são aqueles cujas informações tratam do mesmo assunto. Esta tese tem por objetivo investigar a especificação, a instanciação e a experimentação de um arcabouço para apoiar a tarefa de criação automática de ligações hipertexto entre repositórios homogêneos. O arcabouço proposto, denominado CARe (Criação Automática de Relacionamentos), é representado por um conjunto de classes que realizam a coleta de informações a serem relacionadas e que processam essas informações para a geração de índices. Esses índices são relacionados e utilizados na criação automática de ligações hipertexto entre a informação original. A definição do arcabouço se deu após uma fase de análise de domínio na qual foram identificados requisitos e construídos componentes de software. Nessa fase, vários protótipos também foram construídos de modo iterativo / With the evolution of the Internet, distinct communication media have focused on the Web as a channel of information publishing. An immediate consequence is an abundance of sources of information and writing styles in the Web. This effect, combining with the inherent curiosity of human beings, has led Web users to look for more than a single article about a same subject. To gain access to separate on a same subject, readers need to search, read and analyze information provided by different sources of information. Besides consuming a great amount of time, that activity imposes a cognitive overhead to users. Several hypermedia researches have investigated mechanisms for supporting users during the process of identifying information on homogeneous repositories, available or not on the Web. In this thesis, homogeneous repositories are those containing information that describes a same subject. This thesis aims at investigating the specification and the construction of a framework intended to support the task of automatic creation of hypertext links between homogeneous repositories. The framework proposed, called CARe (Automatic Creation of Relationships), is composed of a set of classes, methods and relationships that gather information to be related, and also process that information for generating an index. Those indexes are related and used in the automatic creation of hypertext links among distinct excerpts of original information. The framework was defined based on a phase of domain analysis in which requirements were identified and software components were built. In that same phase several prototypes were developed in an iterative prototyping
362

CHP: chapas de partículas homogêneas - madeiras do Nordeste do Brasil / CHP: foils of homogeneous particles - wood of the Northeast of Brasil

Nascimento, Maria Fátima do 28 March 2003 (has links)
No desenvolvimento deste trabalho foram analisados conceitos e propostas visando evidenciar a possibilidade de mudanças tecnológicas para favorecer o crescimento sócio-econômico da região do nordeste do Brasil. Sobre ela ainda paira um conceito pré-estabelecido: trata-se de região sem possibilidade de prover suas próprias necessidades. É preciso reverter esta situação com a melhoria das condições de vida dos habitantes do sertão nordestino por meio da implementação das idéias como as relacionadas ao reflorestamento e ao desenvolvimento sustentável. A presente proposta tem como foco a utilização das espécies de madeiras do nordeste, abrangendo as que resistem à prolongada estiagem da região. São sugeridos os procedimentos para a fabricação de chapas de partículas com matéria prima das espécies: Angico (Anadenanthera macrocarpa), Algaroba (Prosopis juliflora) e Jurema Preta (Mimosa tenuiflora), todas freqüentes na região nordeste do Brasil. Também são apresentados os resultados das propriedades físicas e mecânicas: densidade, inchamento, absorção, intemperismo artificial, resistência à tração paralela às faces; módulo de ruptura, limite de proporcionalidade e módulo de elasticidade na flexão estática, e arrancamento de parafusos. Os ensaios foram realizados segundo as recomendações do documento normativo 1037:1996, da ASTM. Os resultados foram comparados com as propriedades das chapas usualmente comercializadas, obtendo-se valores altamente satisfatórios. / In the development of this work, concepts were analyzed and proposed seeking to evidence the possibility of technological changes for the socio-economic growth of the Brazilian northeast region. It still hovers a pré-established concept about Brazilian northeast: it is treated as an area without possibility of providing its own needs. It is necessary to revert this situation with the improvement of its life conditions through the execution of the ideas as the related to the reforestation and to the maintainable development. The present proposal has as focus the use of northeast wood species, embracing the ones that resist prolonged drought of the area. Procedures are suggested to the production of particleboard with the species: Angico (Anadenanthera macrocarpa), Algaroba (Prosopis juliflora) and Juremapreta (Mimosa tenuiflora), all frequent in the northeast area of Brazil. The results of the physical and mechanical properties are also presented: density, thickness swelling, absorption, artificial weathering, natural weathering, tension parallel to surface, tension perpendicular to surface, modulus of rupture, proportionality limit and modulus of elasticity in the static bending, and nail-head withdrawal test. The rehearsals were accomplished according to the recommendations of the normative document: 1037/1996, ASTM. The results were compared with the properties of the usually marketed boards, and high satisfactory values were obtained.
363

Étude des sous-variétés dans les variétés kählériennes, presque kählériennes et les variétés produit / Study of submanifolds of Kaehler manifolds, nearly Kaehler manifolds and product manifolds

Moruz, Marilena 03 April 2017 (has links)
Cette thèse est constituée de quatre chapitres. Le premier contient les notions de base qui permettent d'aborder les divers thèmes qui y sont étudiés. Le second est consacré à l'étude des sous-variétés lagrangiennes d'une variété presque kählérienne. J'y présente les résultats obtenus en collaboration avec Burcu Bektas, Joeri Van der Veken et Luc Vrancken. Dans le troisième, je m'intéresse à un problème de géométrie différentielle affine et je donne une classification des hypersphères affines qui sont isotropiques. Ce résultat a été obtenu en collaboration avec Luc Vrancken. Et enfin dans le dernier chapitre, je présente quelques résultats sur les surfaces de translation et les surfaces homothétiques, objet d'un travail en commun avec Rafael López. / Abstract in English not available
364

Développement du soudage MIG CMT pour la réparation de pièces aéronautiques. Application aux pièces en alliage base aluminium 6061 / Development of MIG CMT welding for aeronautical parts repair. Application to 6061 aluminium alloy parts

Benoit, Alexandre 07 December 2012 (has links)
Cette étude répond à une demande industrielle de réparation d’une pièce aéronautique en alliage d’aluminium 6061 à l’aide d’un procédé de soudage à l’arc. La première partie est consacrée à la comparaison des procédés Metal Inert Gas (MIG), MIG pulsé, Tungsten Inert Gas et MIG Cold Metal transfer (CMT). C’est ce dernier procédé qui a été sélectionné pour ses aptitudes particulières, comme son bon contrôle des paramètres et le faible endommagement produit dans le métal de base. Puis, deux métaux d’apport ont été testés – les alliages 5356 et 6061 – avec deux stratégies de réparation : le soudage et le rechargement. Les résultats d’essais mécaniques ont démontré que le rechargement avec l’aluminium 5356 est l’option la plus adaptée pour cette application. Les essais sur pièce réelle ont prouvé la pertinence de cette approche.La zone affectée thermiquement générée, dans l’alliage 6061, par les procédés de soudage à l’arc a également été caractérisée. Il a été mis en évidence une variation de la microstructure associée aux changements de propriétés mécaniques de cette zone. Enfin, les essais exploratoires de soudage homogène à l’arc, c’est-à-dire, avec le métal d’apport en 6061, ont prouvé qu’il était possible, dans certaines conditions, de souder sans générer de fissuration, bien que, cet aluminium soit réputé comme étant insoudable de cette manière. / This study responds to an industrial demand of repair using an arc welding process. It concerns an aeronautical piece made in 6061 aluminium alloy. The first part of the study is devoted to the comparison of processes Metal Inert Gas (MIG), pulsed MIG, Tungsten Inert Gas and MIG Cold Metal Transfer (CMT). It is the latter process that was selected for its special abilities, such as its good control of parameters and the low damaging produced in the base metal. Then, two filler alloys were tested – 5356 and 6061 aluminium alloys– with two repairing strategies : welding and building up. The results of mechanical tests showed that building up with aluminum 5356 is most suitable option for this application. The trials on the real piece showed the relevance of this approach.The heat affected zone generated by the arc welding process in the 6061 base metal was also characterized. It was shown a varaition of microstructure associated with the change of mechanical properties in this zone. Finally, exploratory trials of homogeneous arc welding, i.e., with the 6061 filler alloy showed that it was possible, with certain conditions, to weld without generating weld cracking, although, this aluminium is deemed unweldable by this way.
365

Nouveaux catalyseurs d’hydrosilylation pour la synthèse de silicones / New catalysts for alkene hydrosilylation and synthesis of silicones

Puillet, Magali 12 October 2018 (has links)
L’hydrosilylation d’alcènes est une réaction clé pour la synthèse d’huiles silicones fonctionnelles et d’élastomères silicones nécessite un catalyseur. Industriellement, le platine est utilisé or le coût important de ce métal motive la recherche de catalyseurs alternatifs plus compétitifs, notamment à base de métaux non précieux. Les travaux ont débuté sur des systèmes développés précédemment au laboratoire à base de cobalt et de nickel à haut degré d’oxydation et de ligands dicétones. Les cinétiques de réticulation ont été également suivies aussi bien par des mesures qualitatives d’arrêt d’agitation que par des mesures de rhéologie ou de chaleur de réaction par DSC. Ces catalyseurs sont actifs et robustes pour la réticulation. A la suite, des catalyseurs à base de cobalt portant en particulier des ligands amidures ont été étudiés. Associés à un ligand bidentate (P,N), les systèmes catalytiques sont compétitifs au platine de Karstedt pour l’hydrosilylation sélective d’alcènes. Ces catalyseurs réalisent également la réticulation d’huiles silicones à relativement basse température (20 min à 90°C). Un homologue au fer s’est également montré actif pour la réticulation d’huiles silicones démontrant la faisabilité d’une voie catalytique d’hydrosilylation à partir de complexes de fer non toxiques et robustes / Alkene hydrosilylation is a major tool for the synthesis of functionalized silicone oils and silicone elastomers and is catalyzed by transition metal complexes. Industrially, Platinum complexes are used. However, high and volatile cost and rarity of precious metals lead to the development of competitive alternative systems, especially catalysts based on non-precious transition metals. First, Nickel and Cobalt high-oxidation-state complexes bearing diketone ligands were studied. Those systems had been previously developed in the laboratory and the study has been completed. Crosslinking kinetics were followed by qualitative measures of “stop-stirring” time and by rheology and thermal analysis (DSC). Those catalysts are active over oxygen and stable for silicone-oil crosslinking. Then, Cobalt Catalysts bearing amido-based ligands were studied. When associated with a ligand (phosphino pyridine P,N), those systems are competitive with the Karstedt catalyst (Pt) for selective alkene hydrosilylation. They also allow for silicone-oil crosslinking at relatively low temperature (20 min at 90 °C). Finally, a homologous complex based on Iron was synthesized and showed activity for silicones’ crosslinking evidencing the feasibility of a catalytic hydrosilylation pathway from non-toxic and robust iron complexes.
366

Conversion of renewable feedstocks into polymer precursors and pharmaceutical drugs

Shi, Yiping January 2018 (has links)
Fossils fuels are highly demanded in everyday life domestically or industrially. Fossil fuels are finite resources and they are rapidly depleting, as such alternative renewable feedstocks are sought to replace fossil fuels. Tall oil from paper processing and cashew nut shell liquid from the cashew nut industry are the two major renewable sources we studied, they are both waste byproducts, and have the potential to be converted into value-added materials. Tall oil from the paper industry mainly contained tall oil fatty acid, and under isomerising methoxycarbonylation with palladium catalyst, dimethyl 1,19-dimethyl nonadecanedioate can be obtained. This difunctional ester, dimethyl 1,19-dimethyl nonadecanedioate, is converted to diols, secondary and primary diamines by a hydrogenation reaction with ruthenium complexes of 1,1,1-tris(diphenylphosphinometyl)ethane (triphos) as catalysts in the presence of water, amine or aqueous ammonia respectively. In the case of aqueous ammonia it is necessary to use a two step reaction via diol to obtain 1,19-diaminononadecane. Diesters, diols and diamines are useful precursors for the synthesis of polyesters and polyamides. Difunctional substrates with 8-19 carbon chains are all tolerated under the reaction conditions and are successfully converted to the corresponding diols and diamines in high yields. Under similar hydrogenation conditions with the same ruthenium catalyst, cyclic products were predominantly produced with decreased chain length. N-heterocycles, which are important building blocks for the synthesis of drug molecules, were formed from the hydrogenation of diesters with 4-7 carbon chains in the presence of an amine. Another polymer precursor, ε-caprolactam, which is the precursor for Nylon 6, is obtained in a reasonable yield from both adipic acid and adipate esters together with aqueous ammonia in the presence of ruthenium catalyst. Cashew nut shell liquid was also converted into useful medical drugs, such as norfenefrine, rac-phenylephrine, etilefrine and fenoprofene in reasonable yields. Most of these drug molecules have been formed from 3-vinylphenol by catalytic hydroxyamination followed by methylation or ethylation. 3-Vinylphenol was synthesised from cardanol by ethenolysis to 3-non-8-enylphenol followed by isomerising ethenolysis, whilst the N-alkylation reactions used methyl or ethyl triflate to avoid dialkylation. Fenoprofene was formed by firstly O-phenylating cardanol then ethenolysis followed by isomerising ethenolysis to form 1-phenoxy-3-vinylbenzene. Methoxycarbonyation followed by hydrolysis formed the final product in good yield. Our methods start from renewable waste materials and avoid unpleasant reagents in the original stoichiometric synthesis of those drugs, for example, cyanide is no longer essential for the synthesis of fenoprofene.
367

Análise de guias de ondas pelos métodos vetorial magnético e dos elementos-finitos / Waveguide analysis by the methods magnetic vector and finite element

Alexsandro Nogueira Reis 28 March 2011 (has links)
Neste trabalho, é apresentada uma formulação apropriada à análise de guias de ondas eletromagnéticos, cobrindo do espectro de microondas até o da óptica. Nas regiões a partir do ultravioleta, os comprimentos de onda são equivalentes às dimensões atômicas e a formulação necessita de uma abordagem quântica, que não é considerada neste estudo. A formulação é fundamentada nos métodos vetorial magnético e dos elementos finitos (MEF), em meios não homogêneos, anisotrópicos e não dissipativos, embora a dissipação possa ser facilmente introduzida na análise. Deu-se preferência à formulação com o campo magnético em vez do elétrico, pelo fato do campo magnético ignorar descontinuidades elétricas. Ele é contínuo em regiões de permeabilidade homogênea, propriedade dos meios dielétricos em geral ( = 0), independente da permissividade dos respectivos meios, conquanto os campos elétricos sejam descontínuos entre regiões de permissividades diferentes. / This work presents a suitable formulation to the analysis of electromagnetic waveguide, covering the spectrum of the microwave to optics. In regions from the ultraviolet, the wavelengths are equivalent to atomic dimensions and the design needs a quantum approach, which is not considered in this study. The formulation is based on the magnetic vector and the finite element methods (FEM), in non-homogeneous, anisotropic and non-dissipative dielectric materials, while the dissipation can be easily introduced in the analysis. Preference was given to the formulation with the magnetic field, because the magnetic field ignores electrical discontinuities. It is continuous in regions of homogeneous permeability, property of all dielectric materials (=0), independent of the permissiveness of respective regions, while electric fields are discontinuous between regions of different permittivities.
368

Rigidez de superfícies convexas em espaços homogêneos 3-dimensionais

Alcântara, Marcos Aurélio de 03 April 2013 (has links)
Made available in DSpace on 2015-04-22T22:16:05Z (GMT). No. of bitstreams: 1 Marcos Aurelio de Alcantara.pdf: 720745 bytes, checksum: 08ea1f8125881d86a363610223d345ea (MD5) Previous issue date: 2013-04-03 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / This paper presents main result of a theorem in rigidity of convex three dimensional homogeneous spaces, which was proved by Hosenberg and Tribuzy in 2011. More precisely, we prove that given smooth family of isometric immersions strictly convex f(t) : M 􀀀! N, with f(0) = f, Ke(ft(x)) = Ke(f(x)) for x 2 M and for all t, and H(ft(x)) = H(f(x)) in three distinct points x of M. Then there are isometries h(t) : N 􀀀! N such that h(t)f(t) = f. / Este trabalho apresenta como principal resultado um teorema de rigidez de superfícies convexas em espaços homogêneos tridimensionais, que foi provado por Hosenberg e Tribuzy em 2011. Mais precisamente, provaremos que dada uma família suave de imersões isométricas estritamente convexa f(t) : M 􀀀! N, com f(0) = f, Ke(ft(x)) = Ke(f(x)) para x 2 M e todo t, e H(ft(x)) = H(f(x)) em três pontos distintos x de M. Então existem isometrias h(t) : N 􀀀! N tal que h(t)f(t) = f.
369

Tratamento de efluente farmacêutico veterinário por meio de ozonização catalítica homogênea em presença de íons Ferro / Treatment of veterinary pharmaceutical by Catalytic Homogeneous Ozonization with iron ions

Lívia Martins Pereira 13 October 2014 (has links)
A indústria farmacêutica acarreta a geração de uma quantidade significante de resíduos potencialmente poluidores. Ao serem lançados em corpos d\'água, os efluentes das indústrias farmacêuticas provocam desequilíbrio no ambiente, por transportarem compostos de difícil degradação. A ocorrência desses resíduos no ambiente pode favorecer a resistência de microrganismos frente a esses fármacos, além de causar problemas de ordem toxicológica a determinados organismos vivos. No intuito de minimizar os impactos causados pelos despejos dos efluentes desta atividade industrial, torna-se necessário estudar tratamentos alternativos para degradação de tais resíduos. Esta pesquisa teve como proposta avaliar um Processo Oxidativo Avançado: Ozonição Catalítica Homogênea em presença de íons Fe2+ como técnica para tratamento de efluente veterinário, para tanto foram estudados três diferentes reatores em sistema contínuo. Na primeira etapa do estudo, foi definido o modelo de reator mais adequado para o tratamento desse efluente farmacêutico veterinário. Na segunda etapa do estudo, utilizou-se um planejamento fatorial fracionado 24-1 para otimizar as variáveis do processo: pH, concentração de Fe2+ g/L, potência do ozonizador (vazão mássica de O3) e vazão de saída do efluente do reator. A eficiência do tratamento foi avaliada por meio da redução de Carbono Orgânico Total (COT) (%). Este estudo mostrou que a condição experimental na qual se observou a maior porcentagem de redução de COT (46,14%) ocorreu quando se combinou pH 4,0, [Fe2+] de 0,5 g/L, vazão de saída do reator de 1,23 L/h e potência do ozonizador de 56W. A avaliação estatística desse planejamento apontou para uma nova configuração experimental na qual se obteve 55,24% de redução de COT, degradação do ativo Fenbendazol de 71,24% e degradação do ativo Triclabendazol de 95,68%. Essa nova configuração combinou pH 4,0, [Fe2+] de 0,1g/L, vazão de saída do reator de 1,85 L/h e potência de 56W. / The pharmaceutical industry generates a significant amount of potentially polluting waste. When released into stream, the pharmaceutical effluents cause imbalance in the environment, transporting compounds are difficult to degrade. The occurrence of these residues in the environment can improve the microbial resistance of these drugs and cause toxicological implication of certain organisms. In order to minimize the impacts caused by discharges of effluents of this industrial activity, it is necessary to study alternative treatments for degradation of the waste. The purpose of this work was to evaluate proposed system using continuous reactors as one treatment technique Advanced Oxidative Process: Catalytic Homogeneous Ozonization with Fe2+. In the first stage of the study, the reactor model more suitable for treatment of this veterinary pharmaceutical effluent. In the second stage of the study, used a design factorial 24-1to optimize the variables of the process: pH, concentration of Fe2+ g/L, ozoniser power and output flow reactor. The efficiency of the treatment was evaluated by the reduction of Total Organic Carbon rate (TOC) (%). This study showed that the experimental condition in which it was observed the highest percentage of TOC reduction (46.14%) occurred when combined pH 4.0, [Fe 2 +] 0.5 g / L, the output flow reactor 1.23 L / h and ozoniser power of 56W. The statistical evaluation of this planning pointed to a new experimental setup in which we obtained 55.24% reduction of TOC, degradation of drug Fenbendazole 71.24% and degradation of 95.68% drug Triclabendazole. This new configuration combined pH 4.0, [Fe 2 +] of 0.1 g / L, output flow reactor of 1.85 L / h and ozoniser power of 56W.
370

Ozonização catalítica do chorume proveniente do antigo aterro controlado da cidade de Guaratinguetá-SP utilizando os íons Fe2+, Fe3+, Zn2+, Mn2+, Ni2+ e Cr3+ / Homogeneous catalytic ozonation of leachate from Guaratinguetá - SP landfill, using the ions Fe2+, Fe3+, Zn2+, Mn2+, Ni2+ e Cr3+

André Luís de Castro Peixoto 14 May 2008 (has links)
Durante anos, o lixo da cidade de Guaratinguetá foi aterrado e o seu produto recalcitrante não passou por nenhum tratamento físico ou mesmo químico, percolando diretamente sob o aterro. Mesmo tendo sido desativado e transformado em Parque Ecológico, o material depositado no local ao longo dos anos, continuará a ser decomposto por microrganismos e continuará a ser produzido o lixiviado como fonte de poluição ambiental. Inicialmente, fez-se a caracterização do chorume \"in natura\", demonstrando-se como fonte de matéria orgânica recalcitrante, com massa molar característica de macromoléculas (5,58 kDa e polidispersidade de 1,16), DBO não determinável pela recalcitrância molecular e/ou pela ação tóxica e DQO característica de lixiviado estabilizado (1.013 mg L-1). A fração inorgânica total, dada pela quantidade de sólidos fixos, foi de 3.670 mg L-1, valor esse 3,6 vezes maior que a fração orgânica. O estudo de tratamento do chorume, por ozonização catalítica homogênea foi desenvolvido, principalmente, pelo uso seqüencial de dois arranjos ortogonais de Taguchi, sendo o primeiro, matriz L16, para estudo exploratório dos fatores mais importantes na redução percentual da DQO. Os fatores estudados foram vazão de ozônio, concentração dos íons Fe2+, Fe3+, Zn2+, Mn2+, Ni2+ e Cr3+, pH do meio reacional e presença/ausência de fonte de radiação UV (254 nm). Dentre os metais de transição, os íons Fe2+ e Fe3+ demonstraram-se como mais viáveis como catalisadores na geração de radicais livres hidroxilas devido à sua significância estatística (p = 0,005), e por terem maior tolerância ao descarte no meio ambiente (menor toxicidade) frente aos demais íons. Com a utilização do arranjo ortogonal L8 de Taguchi, foi possível atingir degradação máxima de DQO da ordem de 50 %. A melhor configuração dos fatores, visando aumentar o percentual de redução da DQO foi: vazão de ozônio igual a 5 L h-1 (589,9 mg h-1 O3), concentração de íon de íon ferroso igual a 10 mg L-1, concentração de íon férrico igual a 5 mg L-1 e pH 5. / During many years, the garbage of Guaratinguetá city was landfilled and its recalcitrant product was not submitted to any physical or chemical treatment, leaching directly through the area. After deactivating and transforming the landfill into an Ecological Park, the material deposited in the place by the past years, will continue being decomposed by microorganisms and will continue producing the leached one as a mean of environment pollution. Initially, the leachate \"in natura\" was characterized, demonstrating itself as a source of recalcitrant organic substance with a higher molecular size characteristic of 5,58 kDa and polidispersity of 1,16 and stabilized effluent (not determinable DBO due to molecular recalcitrance and/or toxicity and DQO of 1,013 mg L-1). The total inorganic fraction, given by the amount of total fixed solids was 3,670 mg L-1, which means 3,6 times bigger than the organic fraction. The study of leachate treatment by homogeneous catalytic ozonation was given, mainly, for the sequential use of two Taguchi\'s orthogonal arrangements, being the first, L16 design, for exploratory studies of the most important factors in the percentual reduction of DQO. The factors studied were the ozone outflow, the Fe2+, Fe3+, Zn2+, Mn2+, Ni2+ and Cr3+ ions concentration, the reaction medium pH and the presence/absence of UV radiation source UV (254 nm). Amongst the transition metals, Fe2+ and Fe3+ ions have demonstrated to be as more viable as free hydroxyl radicals catalyst due to its statistics significance (p = 0,005) and also because they have a greater tolerance to the environment discarding (less toxicity) compared to the other ions. The use of L8 Taguchi\'s orthogonal arrays gives the possibility to reach 50 % maximum COD depletion. The best factors configuration, using COD percentage reduction as experimental design response was: 5 L h-1 (589,9 mg h-1 O3) ozone outflow, 10 mg L-1 ferrous concentration, 5 mg L-1 ferric ion concentration and pH 5.

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