xv, 177 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / In this dissertation, three different topics related to terascale physics are explored. First, a new method is suggested to match next-to-leading order (NLO) scattering matrix elements with parton showers. This method is based on the original approach which adds primary parton splittings in Born-level Feynman graphs in order to remove several types of infrared divergent subtractions from the NLO calculation. The original splitting functions are modified so that parton showering has a less severe effect on the jet structure of the generated events. We also examine the Large Hadron Collider phenomenology of quantum black holes in models of TeV scale gravity. Based on a few minimal assumptions, such as the conservation of color charges, interesting signatures are identified that should be readily visible above the Standard Model background. The detailed phenomenology depends heavily on whether one requires a Lorentz invariant, low-energy effective field theory description of black hole processes. Finally, in the calculation of cross sections in high energy collisions at NLO, one option is to perform all of the integrations, including the virtual loop integration, by Monte Carlo numerical integration. A new method is developed to perform the loop integration directly, without introducing Feynman parameters, after suitably deforming the integration contour. Our example is the N-photon scattering amplitude with a massless electron loop. Results for six photons and eight photons are reported. / Committee in charge: Stephen Hsu, Chairperson, Physics; Graham Kribs, Member, Physics; David Strom, Member, Physics; Davison Soper, Member, Physics; Marina Guenza, Outside Member, Chemistry

abstract: In this thesis, a single-level, multi-item capacitated lot sizing problem with setup carryover, setup splitting and backlogging is investigated. This problem is typically used in the tactical and operational planning stage, determining the optimal production quantities and sequencing for all the products in the planning horizon. Although the capacitated lot sizing problems have been investigated with many different features from researchers, the simultaneous consideration of setup carryover and setup splitting is relatively new. This consideration is beneficial to reduce costs and produce feasible production schedule. Setup carryover allows the production setup to be continued between two adjacent periods without incurring extra setup costs and setup times. Setup splitting permits the setup to be partially finished in one period and continued in the next period, utilizing the capacity more efficiently and remove infeasibility of production schedule. The main approaches are that first the simple plant location formulation is adopted to reformulate the original model. Furthermore, an extended formulation by redefining the idle period constraints is developed to make the formulation tighter. Then for the purpose of evaluating the solution quality from heuristic, three types of valid inequalities are added to the model. A fix-and-optimize heuristic with two-stage product decomposition and period decomposition strategies is proposed to solve the formulation. This generic heuristic solves a small portion of binary variables and all the continuous variables rapidly in each subproblem. In addition, the case with demand backlogging is also incorporated to demonstrate that making additional assumptions to the basic formulation does not require to completely altering the heuristic. The contribution of this thesis includes several aspects: the computational results show the capability, flexibility and effectiveness of the approaches. The average optimality gap is 6% for data without backlogging and 8% for data with backlogging, respectively. In addition, when backlogging is not allowed, the performance of fix-and-optimize heuristic is stable regardless of period length. This gives advantage of using such approach to plan longer production schedule. Furthermore, the performance of the proposed solution approaches is analyzed so that later research on similar topics could compare the result with different solution strategies. / Dissertation/Thesis / Masters Thesis Industrial Engineering 2015

abstract: Thermodynamic development and balance of plant study is completed for a 30 MW solar thermochemical water splitting process that generates hydrogen gas and electric power. The generalized thermodynamic model includes 23 components and 45 states. Quasi-steady state simulations are completed for design point system sizing, annual performance analysis and sensitivity analysis. Detailed consideration is given to water splitting reaction kinetics with governing equations generalized for use with any redox-active metal oxide material. Specific results for Ceria illustrate particle reduction in two solar receivers for target oxygen partial pressure of 10 Pa and particle temperature of 1773 K at a design point DNI of 900 W/m2. Sizes of the recuperator, steam generator and hydrogen separator are calculated at the design point DNI to achieve 100,000 kg of hydrogen production per day from the plant. The total system efficiency of 39.52% is comprised of 50.7% hydrogen fraction and 19.62% electrical fraction. Total plant capital costs and operating costs are estimated to equate a hydrogen production cost of $4.40 per kg for a 25-year plant life. Sensitivity analysis explores the effect of environmental parameters and design parameters on system performance and cost. Improving recuperator effectiveness from 0.7 to 0.8 is a high-value design modification resulting in a 12.1% decrease in hydrogen cost for a modest 2.0% increase in plant $2.85M. At the same time, system efficiency is relatively inelastic to recuperator effectiveness because 81% of excess heat is recovered from the system for electricity production 39 MWh/day and revenue is $0.04 per kWh. Increasing water inlet pressure up to 20 bar reduces the size and cost of super heaters but further pressure rises increasing pump at a rate that outweighs super heater cost savings. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2018

High-performance fibres such as carbon, glass and kevlar are very promising for aerospace applications because of their high strength, stiffness, impact damage and excellent fatigue life. The high cost of the prepreg materials such as pre-impregnated fibre tape/tow and fabrics, and limitations of existing manufacturing processes are a big challenge for the aerospace industry to meet increasing performance demands. Their benefits can only be achieved by using low cost materials and manufacturing methods. In the past three or four decades, there have been substantial technological developments, which are governed by the new materials and their associated manufacturing techniques. The production of carbon fibre is slow and capital intensive, therefore, carbon manufactures produce higher tow counts (number of filaments) to increase production through-put in order to reduce its cost. In other words, 12k carbon tow is much cheaper than 6k or 3k carbon tow. In many applications finer tows are desirable. In this thesis, a fully automated laser feedback tow splitting line has been developed to split higher tow counts (12k spool) into smaller tow counts (split into 6k spools) in order to produce low cost material. The quality of the split tows has been evaluated by recording the data online during the splitting process. The recorded data was later analysed by statistical tools. A four axis modular gantry robotic system has been developed at the University of Manchester in order to deposit dry fibres in a completely flexible manner. To facilitate robotic preforming, an end-effector and mould have been designed and developed in this research. The tow placement program was written in the CoDeSys software which is then uploaded into the motion controller to perform specific motions. The cross-ply laminates have been manufactured by the proposed robotic system using split 6k (produced by the tow splitting process) and original 12k carbon tows. Mechanical test of both composites (12k and split 6k) are presented. A tufting process has been developed and conducted by the robotic system in order to manufacture 3D preforms. The tufted composite was compared with 3D woven and stitched 2D broadcloth in terms of the tensile and interlaminar shear strength properties. X-ray tomography has been conducted to investigate preform geometrical variations of manufactured composites. In addition, preforming cost models have been developed for robotic fibre placement and 3D weaving.

Cette thèse aborde la résolution des problèmes d'interaction fluide-structure par un algorithme consistant en un couplage entre deux solveurs : un pour le fluide et un pour la structure. Pour assurer la cohérence entre les maillages fluide et structure, on considère également une discrétisation de chaque domaine par volumes finis. En raison des difficultés de décomposition du domaine en sous-domaines, nous considérons pour chaque environnement un algorithme parallèle de multi-splitting (ou multi-décomposition) qui correspond à une présentation unifiée des méthodes de sous-domaines avec ou sans recouvrement. Cette méthode combine plusieurs applications de points fixes contractantes et nous montrons que, sous des hypothèses appropriées, chaque application de points fixes est contractante dans des espaces de dimensions finies normés par des normes hilbertiennes et non-hilbertiennes. De plus, nous montrons qu'une telle étude est valable pour les résolutions parallèles synchrones et plus généralement asynchrones de grands systèmes linéaires apparaissant lors de la discrétisation des problèmes d'interaction fluide-structure et peut être étendue au cas où le déplacement de la structure est soumis à des contraintes. Par ailleurs, nous pouvons également considérer l’analyse de la convergence de ces méthodes de multi-splitting parallèles asynchrones par des techniques d’ordre partiel, lié au principe du maximum discret, aussi bien dans le cadre linéaire que dans celui obtenu lorsque les déplacements de la structure sont soumis à des contraintes. Nous réalisons des simulations parallèles pour divers cas test fluide-structure sur différents clusters, en considérant des communications bloquantes et non bloquantes. Dans ce dernier cas nous avons eu à résoudre une difficulté d'implémentation dans la mesure où une erreur irrécupérable survenait lors de l'exécution ; cette difficulté a été levée par introduction d’une méthode assurant la terminaison de toutes les communications non bloquantes avant la mise à jour du maillage. Les performances des simulations parallèles sont présentées et analysées. Enfin, nous appliquons la méthodologie présentée précédemment à divers contextes d'interaction fluide-structure de type industriel sur des maillages non structurés, ce qui constitue une difficulté supplémentaire.

O processo de especiação é lento e gradual e a não completa compreensão deste processo ao longo da história do conhecimento nos remete a problemas clássicos sobre a classificação dos organismos. Neste trabalho, conduzimos um estudo sobre os padrões filogeográficos e evolutivos de duas espécies irmãs parapátricas de sapinhos de barriga-vermelha Melanophryniscus dorsalis e M. montevidensis, listadas como mundialmente ameaçadas segundo a IUCN , além de um estudo aplicado com o uso de modelos de nicho ecológico identificando áreas de interesse a conservação para ambas as espécies. Através dos modelos consensos baseados nos algoritmos BIOCLIM, GARP e Máxima entropia e da análise de “Hotspot” áreas de alta adequabilidade ambiental foram identificadas para ambas as espécies. A validação em campo de modelos preliminares indicou a ausência de indivíduos em locais de alta adequabilidade. Expedições a campo também revelaram uma série de novos pontos de ocorrência, entre os limites da distribuição, e a confirmação de registros historicamente omitidos por listas regionais, nacional e mundial de espécies ameaçadas. Para este estudo propomos cinco “hotspots” de grande interesse na conservação e preservação de ambas as espécies. Os dados moleculares, obtidos através do Cytb e COI, indicam claramente um processo de especiação ocorrendo com M. dorsalis e M. montevidensis com um ancestral comum para ambas as espécies datando entre 3 e 3,5 milhões de anos. A rede da haplótipos, para ambas as espécies nos dois marcadores, é do tipo estrela com um haplótipo central e uma série de outros com uma ou poucas mutações partindo do haplótipo central, indicando expansão demográfica e também demonstrando alta variabilidade. A população mais ao norte de M. dorsalis, na localidade de Mar Grosso no município de Laguna (SC), merece uma atenção especial por se tratar de uma Unidade de Manejo (UM) por seus indivíduos apresentarem uma viii frequência única de alelos. Segundo a definição de UM, a estratégia indicada para esta população é a delimitação de uma área específica e monitoramento da população. Os resultados obtidos neste trabalho provêm um conjunto de informações importantes em nível específico para a implementação de um banco de dados nacional sobre espécies ameaçadas. Os dados gerados neste estudo também serão integrados ao Plano Nacional de Ação para a conservação e preservação dos anfíbios e répteis ameaçados de extinção da região sul do Brasil (PAN SUL) gerido pelo Instituto Chico Mendes de conservação da Biodiversidade. / The speciation process is commonly slow and gradual and the incompletely understand of this process throughout the history of knowledge leads us to the classic problems of the organism classification. In this work, we conducted a study on the phylogeographic and evolutionary patterns of two parapatric sister species of red-bellied-toads Melanophryniscus dorsalis and M. montevidensis, listed as globally threatened according to the IUCN, as well as an applied study using ecological niche models to identify areas for conservation interest for both species. Through consensus models based on algorithms BIOCLIM, GARP and Maximum Entropy and the hotspot analysis, areas of high environmental suitability were identified for both species. Field validation of preliminary models also indicated the absence of individuals in areas of high suitability. Field expeditions also revealed new occurrence points within the boundaries of the distribution, and confirmation records historically omitted by regional, national and global lists of threatened species. For this study we propose five hotspots of great interest in the conservation and preservation of both species. Molecular data obtained through Cytb and COI, clearly indicate the speciation process occurring with M. dorsalis and M. montevidensis with a common ancestor to both species dated between 3 and 3.5 million years. The haplotype network for both markers in both species are star-like which consist of a center haplotype with a series of haplotyps with one or few mutations starting from the central haplotype indicates demographic expansion and also shows high variability. The north population found in M. dorsalis, at the locality of Mar Grosso in the city of Laguna, needs special attention because it is a Management Unit (MU) by his individuals present a single frequency alleles. According to the definition of MU, the strategy indicated for this population is the delimitation of a specific area and population monitoring. x The results obtained in this study provide important information set on specific level for the implementation of a national database on endangered species. The generated data in this study will also be integrated into the National Plan of Action for the conservation and preservation of reptiles and amphibians threatened by extinction in southern Brazil (PAN SUL) managed by the Chico Mendes Institute for Biodiversity Conservation.

abstract: Solar energy is a promising alternative for addressing the world's current and future energy requirements in a sustainable way. Because solar irradiation is intermittent, it is necessary to store this energy in the form of a fuel so it can be used when required. The light-driven splitting of water into oxygen and hydrogen (a useful chemical fuel) is a fascinating theoretical and experimental challenge that is worth pursuing because the advance of the knowledge that it implies and the availability of water and sunlight. Inspired by natural photosynthesis and building on previous work from our laboratory, this dissertation focuses on the development of water-splitting dye-sensitized photoelectrochemical tandem cells (WSDSPETCs). The design, synthesis, and characterization of high-potential porphyrins and metal-free phthalocyanines with phosphonic anchoring groups are reported. Photocurrents measured for WSDSPETCs made with some of these dyes co-adsorbed with molecular or colloidal catalysts on TiO2 electrodes are reported as well. To guide in the design of new molecules we have used computational quantum chemistry extensively. Linear correlations between calculated frontier molecular orbital energies and redox potentials were built and tested at multiple levels of theory (from semi-empirical methods to density functional theory). Strong correlations (with r2 values > 0.99) with very good predictive abilities (rmsd < 50 mV) were found when using density functional theory (DFT) combined with a continuum solvent model. DFT was also used to aid in the elucidation of the mechanism of the thermal relaxation observed for the charge-separated state of a molecular triad that mimics the photo-induced proton coupled electron transfer of the tyrosine-histidine redox relay in the reaction center of Photosystem II. It was found that the inclusion of explicit solvent molecules, hydrogen bonded to specific sites within the molecular triad, was essential to explain the observed thermal relaxation. These results are relevant for both advancing the knowledge about natural photosynthesis and for the future design of new molecules for WSDSPETCs. / Dissertation/Thesis / Ph.D. Chemistry 2014

O processo de especiação é lento e gradual e a não completa compreensão deste processo ao longo da história do conhecimento nos remete a problemas clássicos sobre a classificação dos organismos. Neste trabalho, conduzimos um estudo sobre os padrões filogeográficos e evolutivos de duas espécies irmãs parapátricas de sapinhos de barriga-vermelha Melanophryniscus dorsalis e M. montevidensis, listadas como mundialmente ameaçadas segundo a IUCN , além de um estudo aplicado com o uso de modelos de nicho ecológico identificando áreas de interesse a conservação para ambas as espécies. Através dos modelos consensos baseados nos algoritmos BIOCLIM, GARP e Máxima entropia e da análise de “Hotspot” áreas de alta adequabilidade ambiental foram identificadas para ambas as espécies. A validação em campo de modelos preliminares indicou a ausência de indivíduos em locais de alta adequabilidade. Expedições a campo também revelaram uma série de novos pontos de ocorrência, entre os limites da distribuição, e a confirmação de registros historicamente omitidos por listas regionais, nacional e mundial de espécies ameaçadas. Para este estudo propomos cinco “hotspots” de grande interesse na conservação e preservação de ambas as espécies. Os dados moleculares, obtidos através do Cytb e COI, indicam claramente um processo de especiação ocorrendo com M. dorsalis e M. montevidensis com um ancestral comum para ambas as espécies datando entre 3 e 3,5 milhões de anos. A rede da haplótipos, para ambas as espécies nos dois marcadores, é do tipo estrela com um haplótipo central e uma série de outros com uma ou poucas mutações partindo do haplótipo central, indicando expansão demográfica e também demonstrando alta variabilidade. A população mais ao norte de M. dorsalis, na localidade de Mar Grosso no município de Laguna (SC), merece uma atenção especial por se tratar de uma Unidade de Manejo (UM) por seus indivíduos apresentarem uma viii frequência única de alelos. Segundo a definição de UM, a estratégia indicada para esta população é a delimitação de uma área específica e monitoramento da população. Os resultados obtidos neste trabalho provêm um conjunto de informações importantes em nível específico para a implementação de um banco de dados nacional sobre espécies ameaçadas. Os dados gerados neste estudo também serão integrados ao Plano Nacional de Ação para a conservação e preservação dos anfíbios e répteis ameaçados de extinção da região sul do Brasil (PAN SUL) gerido pelo Instituto Chico Mendes de conservação da Biodiversidade. / The speciation process is commonly slow and gradual and the incompletely understand of this process throughout the history of knowledge leads us to the classic problems of the organism classification. In this work, we conducted a study on the phylogeographic and evolutionary patterns of two parapatric sister species of red-bellied-toads Melanophryniscus dorsalis and M. montevidensis, listed as globally threatened according to the IUCN, as well as an applied study using ecological niche models to identify areas for conservation interest for both species. Through consensus models based on algorithms BIOCLIM, GARP and Maximum Entropy and the hotspot analysis, areas of high environmental suitability were identified for both species. Field validation of preliminary models also indicated the absence of individuals in areas of high suitability. Field expeditions also revealed new occurrence points within the boundaries of the distribution, and confirmation records historically omitted by regional, national and global lists of threatened species. For this study we propose five hotspots of great interest in the conservation and preservation of both species. Molecular data obtained through Cytb and COI, clearly indicate the speciation process occurring with M. dorsalis and M. montevidensis with a common ancestor to both species dated between 3 and 3.5 million years. The haplotype network for both markers in both species are star-like which consist of a center haplotype with a series of haplotyps with one or few mutations starting from the central haplotype indicates demographic expansion and also shows high variability. The north population found in M. dorsalis, at the locality of Mar Grosso in the city of Laguna, needs special attention because it is a Management Unit (MU) by his individuals present a single frequency alleles. According to the definition of MU, the strategy indicated for this population is the delimitation of a specific area and population monitoring. x The results obtained in this study provide important information set on specific level for the implementation of a national database on endangered species. The generated data in this study will also be integrated into the National Plan of Action for the conservation and preservation of reptiles and amphibians threatened by extinction in southern Brazil (PAN SUL) managed by the Chico Mendes Institute for Biodiversity Conservation.

Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-07-19T20:29:07Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Thiago André Salgueiro Soares.pdf: 4033349 bytes, checksum: 4a1bb454487e180fb4adfc6bb7d4d5a2 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-07-20T22:05:04Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Thiago André Salgueiro Soares.pdf: 4033349 bytes, checksum: 4a1bb454487e180fb4adfc6bb7d4d5a2 (MD5) / Made available in DSpace on 2018-07-20T22:05:05Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Thiago André Salgueiro Soares.pdf: 4033349 bytes, checksum: 4a1bb454487e180fb4adfc6bb7d4d5a2 (MD5) Previous issue date: 2017-01-25 / CNPQ / Neste trabalho estudou-se a síntese de nanotubos (NT) a partir da liga Ti-75Ta através do processo de anodização e a sua aplicação como fotocatalisador na foto geração de hidrogênio (H₂). Através do planejamento fatorial 2³ completo foi possível a fabricação das nanoestruturas sob diferentes condições de potencial, tempo e temperatura e avaliar os feitos sob o campo elétrico do sistema (densidade de corrente) e a morfologia dos nanotubos (diâmetro e comprimento) e assim obter nanotubos com elevada área superficial especifica (62 m²/g). Os NT TiO₂-Ta₂O₅ sintetizados sob as diferentes condições experimentais foram caracterizados por microscopia eletrônica de varredura (MEV) permitindo mensurar os diâmetros e os comprimentos dos óxidos. As nanoestruturas quando formadas são amorfas necessitando de tratamento térmico para se obter a fase cristalina. A técnica de difração de Raios X (DRX) permitiu estudar a cinética de transformação das fases dos NT TiO₂-Ta₂O₅ e determinar que a temperatura de 800°C é a ideal para a obtenção das fases cristalinas sem danificar as nanoestruturas. Visando a formação de uma nova fase as amostras foram tratadas a 1000°C dando origem a um novo produto identificado como óxido misto de TiTa₂O₇, obtendo uma síntese simples e rápida para a fabricação deste material. A estrutura eletrônica foi avaliada através da técnica de espectroscopia de reflectância difusa, os NT TiO₂-Ta₂O₅ apresentaram band gap de 3,29eV, ao passo que os NT TiTa₂O₇ apresentaram band gap 3,09eV, potencializando a sua aplicação como fotocatalisador na reação de water splitting (WS). Desta forma, tentar combinar o processo de fotogeração de hidrogênio (WS) com a degradação de poluentes orgânicos é uma nova tendência mundial. Neste contexto, o glicerol foi utilizado como agente redutor e demonstrou ser um excelente agente de sacrifício, pois além de auxiliar na separação dos pares elétrons/buracos, apresentou longo tempo de estabilidade sem geração de CO₂ e a sua fotodegradação resultou na formação de dihidroxiacetona, como co-produto de alto valor agregado. Os nanotubos de sintetizados a 800°C apresentaram eficiência de conversão da energia solar em H₂ (STH) de 0,062% enquanto que os óxidos mistos apresentam STH de 0,092% resultados significativos admitindo ue são estruturas simples que permitem melhorias como a adição de catalisadores e dopantes. Além da aplicação como fotocatalisador o TiTa₂O₇ pode ser aplicado como ânodo em baterias de íon de Lítio, produto de grande impacto tecnológico. / In this work the synthesis of nanotubes (NT) from Ti-75Ta alloy (NT TiO₂-Ta₂O₅) was studied through the anodizing process and its application as photocatalyst in the hydrogen (H₂) photogeneration. Through the 2³ factorial design it was possible to fabricate nanostructures under different conditions of potential, time and temperature and to evaluate the effects under electric field of the system (current density) and the morphology of the nanotubes (diameter and length) to obtain nanotubes with Specific surface area (62 m²/g). The NT TiO₂-Ta₂O₅ synthesized as different experimental conditions were characterized by scanning electron microscopy (SEM) allowing to measure the diameters and the lengths of the oxides. As nanostructures when formed are amorphous requiring heat treatment to obtain a crystalline phase. The X-ray diffraction (XRD) technique allowed a transformation kinetics of the NT TiO₂-Ta₂O₅ phases and a temperature of 800 °C is an ideal for obtaining crystalline phases without damaging as nanostructures. Targeting a new phase formation as samples were treated at 1000 ° C to give a new product identified as TiTa₂O₇ mixed oxide, obtaining a simple and rapid synthesis for a manufacture of this material. The electronic structure was evaluated using the diffuse reflection spectroscopy technique, the NT TiO₂-Ta₂O₅ presented a band gap of 3.29eV, whereas the TiTa₂O₇ presented band gap 3.08eV, potentializing its application as a photocatalyst in the reaction of water splitting (WS). In this way, combining the hydrogen photogeneration (WS) process with a degradation of organic pollutants is a new world trend. Glycerol was used as a reducing agent and demonstrated to be an excellent reduction agent, besides assisting in the separation of e-/h+ pairs, presented long time of stability without generation of CO₂ and its photodegradation resulted in the formation of dihydroxyacetone, as coproduct of high added value. The nanotubes synthesized at 800 °C showed the conversion of solar energy to H₂ (STH) of 0.062% since the oxides are mixed have STH of 0.092% significant results admitted that are simple structures that stand out as an addition of noble metal nanoparticles and dopants. In addition to the application as a photocatalyst TiTa₂O₇ can be applied as an anode in Lithium ion batteries.

Os concretos refratários são materiais que apresentam estrutura complexa contendo uma fração de partículas finas (D < 100?m) chamada de matriz e outra mais grosseira da ordem de até centímetros compostas por agregados. Dentre as propriedades importantes durante a aplicação dos concretos refratários, este trabalho aborda principalmente a energia de fratura e a resistência à erosão. Para a avaliação dessas propriedades vários estudos vêm sendo desenvolvidos nos últimos anos. A introdução do método da cunha para propagação estável da trinca é um exemplo, pois este método é utilizado para materiais com estrutura grosseira, como é o caso dos concretos. Já em se tratando de resistência a erosão, pouco se encontra na literatura a respeito desse assunto para concretos refratários. Tendo em vista a aplicação destes materiais, foi avaliado o comportamento da energia de fratura e resistência à erosão de concretos refratário aluminoso convencional antierosivo utilizado na indústria petroquímica com o objetivo de correlacionar os resultados de energia de fratura e a resistência à erosão. Para o desenvolvimento do trabalho foram usados dois concretos a com mesma composição química, variando somente o tamanho de agregado. Foram avaliadas além da energia de fratura e da resistência à erosão outras propriedades foram avaliadas como: os módulos elástico e de ruptura, porosidade aparente, fases cristalinas e microestrutura, e ainda foi realizado um estudo da matriz do concreto. Os resultados mostraram que a energia de fratura aumenta com o aumento do tamanho de agregado para o concreto estudado e a resistência a erosão aumenta com a temperatura de tratamento térmico devido a ceramização da matriz, conforme análise das imagens. Em função dos resultados, pode-se concluir que não foi observada uma boa correlação entre energia de fratura e resistência à erosão. Mas esta correlação de energia de fratura e de resistência à erosão pode ter o mesmo comportamento que a correlação entre comprimento característico e resistência á erosão para faixas específicas de tamanho de agregado. / Castables materials are known to be formed by a complex microstructure containing a fine fraction known as matrix (D<100?m) and another one known as aggregate containing thicker particles up to centimeters in size. Among its most notable properties regarding application, this research primarily addresses to the fracture energy and its erosion resistance. In recent years, some studies have been performed concerning such assessments. As an example, the wedge splitting procedure has been applied in the stable crack propagation method used for some thicker structured materials evaluation such the castables ones. On the other hand, a few data have been gathered concerning castable\'s erosion resistance. Facing such applications the main goal was the study of conventional aluminous anti erosive castables once it has been used in the petrochemical industry in order to correlate fracture energy and erosion resistance results. On this research, two castables samples with the same chemical composition were tested differing only its aggregate particle grain sizes. Besides fracture energy and erosion resistance, other important properties were evaluated as following: elastic modulus, rupture modulus, apparent porosity, crystalline phases and a castable matrix study was also carried out. The results demonstrate an increase on fracture energy as the studied castable aggregate size also increases and according to images studied, the erosion resistance suffers another increment regarding the thermal treatment temperature increase due matrix ceramization. Based on the obtained results, it can be concluded that no observation was made regarding the fracture energy and erosion resistance but it may exist an energy correlation between them once there is some observed between the characteristic length and the erosion resistance concerning the aggregate size range.