The increase in greenhouse gas (GHG) concentrations in the atmosphere, as well as the high rate of depletion of hydrocarbon-based resources have become a global concern. A major source of emissions of hydrocarbon vapours occur during loading and offloading operations in crude oil shuttle tanker transportation. The emitted gases have a typical composition of 60 % N2, 10 % CO2, 5% O2, 5 % C3H8, 10% CH4, 5% C2H6 and 5 % higher hydrocarbons. As a result, various methods aimed to add value to GHG to produce valuable fuels and chemical feedstock are being developed. This work incorporates the use of silica, polyurethane/zeolite and y-type zeolite membrane on an alumina support to selectively permeate methane and carbon dioxide from inert gases and higher hydrocarbons. The recovered gas is upgraded by dry reforming reactions employing rhodium/alumina membrane incorporated into a shell and tube reactor. Mixed gas permeation tests have been carried out with the permeate and feed gases sent to the online gas chromatograph (GC) equipped with a mass spectrometry (MS) detector and an automated 6-port gas sampling valve with a 30 mm HP- Plot Q column. The question is what mesoporous membrane can be highly selective for the separation of methane and carbon dioxide from inert gases and higher hydrocarbons, and what is the effect of temperature and feed gas pressure on the conversion of separated gases? Characterisation of the modified membranes was carried out using nitrogen physisorption measurements and showed the hysteresis isotherms corresponding to type IV and V, which is indicative of a mesoporous membrane. The surface area and the pore size were determined using the Barrett, Joyner, Halenda (BJH) desorption method, which showed the silica membrane had a larger surface area (10.69 m2 g-1) compared to zeolite (0.11 m2 g-1) and polyurethane/zeolite membrane (0.31 m2 g-1). Fourier Transform Infrared spectroscopy, Scanning Electron Microscope and Energy Dispersive X-ray Analysis confirmed the asymmetric deposition of silica, polyurethane, rhodium and zeolite crystals in the matrix of the alumina support. Single gas permeation tests showed that the synthesised y-type zeolite membrane at 293 K had a CH4/C3H8 selectivity of 3.11, which is higher than the theoretical value of 1.65. The permeating CH4 and C3H8 flux at 373 K and a pressure of 1 x 105 Pa was 0.31 and 0.11 mol s-1 m-2 respectively proving that zeolite has molecular sieving mechanism for separation of methane and propane. The silica membrane exhibited higher effectiveness for the separation of CO2 than the other membranes. For methane dry reforming using a supported rhodium membrane, an increase of the reaction temperature from 973 K to 1173 K showed an increase in conversion rate of CO2 and CH4 from less than 20% to over 90% while increasing the gas hourly space velocity (GHSV) did not have a noticeable effect. The study revealed the high potential of the zeolite and rhodium membrane for gas separation and dry reforming reactions concept in creating value-added carbon-based products from CO2 and CH4.

We consider a posteriori error estimators that can be applied to anisotropic tetrahedral finite element meshes, i.e. meshes where the aspect ratio of the elements can be arbitrarily large. Two kinds of Zienkiewicz-Zhu (ZZ) type error estimators are derived which are both based on some recovered gradient. Two different, rigorous analytical approaches yield the equivalence of both ZZ error estimators to a known residual error estimator. Thus reliability and efficiency of the ZZ error estimation is obtained. Particular attention is paid to the requirements on the anisotropic mesh. The analysis is complemented and confirmed by several numerical examples.

Τα δομικά πολυμερή είναι ευαίσθητα σε βλάβες με τη μορφή των ρωγμών, οι οποίες σχηματίζονται βαθιά μέσα στη δομή τους, όπου η ανίχνευση είναι δύσκολη και η επισκευή είναι σχεδόν αδύνατη. Το σπάσιμο οδηγεί σε μηχανική υποβάθμιση των ενισχυμένων με ίνες πολυμερικών σύνθετων υλικών. Στα μικρο-ηλεκτρονικά πολυμερή μπορεί επίσης να οδηγήσει σε ηλεκτρολογική βλάβη. Η ζημία εμφανίζεται σχεδόν σε κάθε σύνθετο υλικό σε μορφή μικρο-ρωγμών που αναπτύσσονται στη εποξειδική μήτρα η οποία δεσμεύει τις ίνες μαζί. Οι μικρο-ρωγμές προκαλούνται από τη θερμική και μηχανική καταπόνηση και είναι ένα μακροχρόνιο πρόβλημα στα εποξειδικά πολυμερή. Ένα in-situ σύστημα αυτόνομης ίασης, με ενσωματωμένες μικρο-κάψουλες και έναν καταλύτη ώστε να προκαλέσει μια αντίδραση μεταθέσεως με άνοιγμα δακτυλίου (ROMP), μπορεί να χρησιμοποιηθεί σε μια προσπάθεια να δεσμεύσει ξανά τις μικρο-ρωγμές. Ανεξάρτητα από την εφαρμογή, αφού έχουν σχηματιστεί ρωγμές εντός πολυμερικών υλικών, η ακεραιότητα της δομής τους είναι σημαντικά μειωμένη. Σε αυτή τη διατριβή γίνεται μελέτη για τη θεραπεία των ζημιών λόγο αποκόλλησης σε εποξειδικά σύνθετα υλικά ενισχυμένα με υφάσματα ινών. Μελετώνται δύο τύποι διαδικασίας επούλωσης. Στον πρώτο, ένα καταλυμένο μονομερές χειροκίνητα εγχέεται στην περιοχή θραύσης λόγω αποφλοίωσης. Στον δεύτερο, περιγράφεται ένα πλήρως ολοκληρωμένο in situ σύστημα με ενσωματωμένες μικρο-κάψουλες και τον καταλύτη τους. Για το πρώτο σύστημα, ελέγχθηκαν δείγματα δοκού διπλής άρθρωσης (DCB) για να μελετηθεί η επούλωση της αποελασματοποίησης σε σύνθετα συγκρίνοντας την ανθεκτικότητα του παρθένου δείγματος με τη σκληρότητα του ίδιου δείγματος μετά την πλήρης επούλωση. Ηλεκτρονική μικροσκοπία σάρωσης (SEM) και Φασματοσκοπία Raman χρησιμοποιούνται για την ανάλυση των επιφανειών θραύσης, ώστε να παρουσιαστούν τα φυσικά στοιχεία της επισκευής. Στη συνέχεια, περιγράφεται η ανάπτυξη ενός πολυμερικής μήτρας σύνθετου υλικού που έχει την ικανότητα να θεραπεύει ρωγμές αυτόματα. Το σύστημα χρησιμοποιεί έναν παράγοντα επισκευής μονομερούς, δικυκλοπενταδιένιο (DCPD), το οποίο είναι αποθηκευμένο σε μικρο-κάψουλες οι οποίες περιέχουν τον υγρό παράγοντα επισκευής, διεσπαρμένες στην εποξειδική μήτρα. Όταν το υλικό έχει υποστεί βλάβη, ρωγμές διαδίδονται μέσω του υλικού σπάζοντας τις μικρο-κάψουλες, απελευθερώνοντας τον παράγοντα επισκευής εντός του επιπέδου της ρωγμής. Τέλος, ο παράγοντας DCPD επισκευής στερεοποιείται με πολυμερισμό μεταθέσεως με άνοιγμα δακτυλίου (ROMP) όταν έρχεται σε επαφή με ένα, με βάση το ρουθήνιο, καταλύτη (Grubbs), ο οποίος διασπείρεται και αυτός εντός της μήτρας. Η διαδικασία με την οποία παρασκευάζονται οι μικρο-κάψουλες γεμάτες με DCPD και οι διάφορες τεχνικές όπως οπτική μικροσκοπία, ηλεκτρονική μικροσκοπία σάρωσης (SEM), διαφορική θερμιδομετρία σάρωσης (DSC), θερμική βαρυμετρική ανάλυση (TGA) και δυναμική μηχανική ανάλυση (DMA) που χρησιμοποιήθηκαν για το χαρακτηρισμό των μικρο-κάψουλων συζητούνται σε αυτήν την εργασία. / Structural polymers are susceptible to damage in the form of cracks, which form deep within the structure where detection is difficult and repair is almost impossible. Cracking leads to mechanical degradation of fibre-reinforced polymer composites; in microelectronic polymeric components it can also lead to electrical failure. Damage occurs in almost every composite material in the form of microcracks that develop in the epoxy matrix that binds the fibers together. Microcracking induced by thermal and mechanical fatigue is also a long-standing problem in polymer adhesives. An in-situ self-healing system uses embedded microcapsules and a catalyst that trigger a romp reaction in an effort to rebond the microcracks. Regardless of the application, once cracks have formed within polymeric materials, the integrity of the structure is significantly compromised. A study of the healing of delamination damage in woven reinforced epoxy composites is performed in this thesis. Two types of healing process are studied. In the first, a catalyzed monomer is manually injected into the delamination. In the second, a fully integrated in situ system is described with embedded microcapsules and catalyst. Double-cantilever-beam (DCB) specimens were tested to study the healing of delamination in composites by comparing the toughness of the virgin specimen with the toughness of the same specimen after healing was complete. Scanning electron microscopy (SEM) and Raman Spectroscopy are used to analyze the fracture surfaces and provide physical evidence of repair. The development of a self-healing polymer-matrix composite material that possesses the ability to heal cracks autonomically is described. The system uses a monomer repair agent, dicyclopentadiene (DCPD), which is stored in an epoxy matrix by dispersing microcapsules containing the liquid repair agent throughout the matrix. When the material is damaged, cracks propagate through the material and break open the microcapsules, releasing the repair agent into the crack plane. Finally, the DCPD repair agent solidifies by ring-opening metathesis polymerization (ROMP) after coming in contact with a ruthenium-based catalyst (Grubbs' catalyst) dispersed in the matrix. The process by which the DCPD-filled microcapsules are prepared and the various techniques such as optical microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA) to characterize the microcapsules are discussed in this work.

Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 205-213). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 100-103).

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 315-346). Available also in a digital version from Dissertation Abstracts.

Orientador: Falcondes Jose Mendes de Seixas / Banca: Luís Carlos Origa de Oliveira / Banca: Luiz Carlos Gomes de Freitas / Resumo: A proposta deste trabalho é analisar o comportamento de transformadores de distribuição trifásicos após a recuperação estudando suas perdas elétricas fixas e variáveis tomando-se o transformador como uma unidade consumidora para demonstrar a viabilidade econômica da reforma, principalmente àquelas que não alteram o núcleo. Foram utilizados os ensaios de rotina de uma empresa recuperadora para uma importante concessionária de distribuição de energia. Este trabalho também faz uma recomendação sobre o descarte deste material segundo conceitos ambientais para uma melhor utilização dos recursos naturais. É importante mencionar o fato que muitos dos transformadores analisados operam a mais de 20 anos. A recuperação permite as concessionárias fornecer energia elétrica para consumidores residenciais e rurais de baixa renda mediante um pequeno investimento na construção de novas linhas de distribuição / Abstract: The purpose of this paper is to analyze the behavior of three-phase distribution transformers when submitted to recovery, taking into consideration fixed and variable electric losses considering the transformer as a consumer unit to demonstrate the economical feasibility, especially those that do not modify the core. It has been used routine tests data obtained from a company that recover for an important power deliver. This paper also deals with the disposal of the material considering environmental concerns, for a better use of natural resources. It is important to mention the fact that many transformers have already operated for more than 20 years. The recover allows the deliver to provide energy to residential or rural low-income consumer through a low investment with the construction of new electric power grid / Mestre

abstract: Asphalt concrete is the most recycled material in the United States and its reclamation allows the positive reuse of the constituent aggregates and asphalt binder, contributing to the long-term sustainability of the transportation infrastructure; decreasing costs, and the total energy and greenhouse emissions embodied into new materials and infrastructure. Although the national trends in Reclaimed Asphalt Pavements (RAP) usage are encouraging, the environmental conditions in Phoenix, Arizona are extreme and needs further consideration. The objective of this research study was to evaluate the viability of using RAP in future pavement maintenance and rehabilitation projects for the City. Agencies in the State of Arizona have been slow adopting the use of RAP as a regular practice. While the potential benefits are great, there is some concern on the impact to long-term pavement performance. RAP millings were sampled from the city’s stockpiles; processed RAP and virgin materials were provided by a local plant. Two asphalt binders were used: PG 70-10 and PG 64-16. RAP variability was evaluated by aggregate gradations; extracted and recovered binder was tested for properties and grading. A mixture design procedure based on the City’s specifications was defined to establish trial blends. RAP incorporation was based on national and local practices. Four different RAP contents were studied 10%, 15%, 25%, and 25% content with a softer binder, in addition to a control mix (0% RAP). Performance tests included: dynamic modulus to evaluate stiffness; Flow Number, to assess susceptibility for permanent deformation (rutting); and Tensile Strength Ratio as a measure of susceptibility to moisture damage. Binder testing showed very stiff recovered asphalts and variable contents with a reasonable variability on aggregate gradations. Performance test results showed slightly higher modulus as RAP content increases, showing a slight improvement related to rutting as well. For moisture damage potential, all mixtures performed well showing improvement for RAP mixtures in most cases. Statistical analysis showed that 0%, 10%, 15% and 25% with softer binder do not present significant statistical difference among mixtures, indicating that moderate RAP contents are feasible to use within the City paving operations and will not affect greatly nor negatively the pavement performance. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018

Submitted by Raquel Vergara Gondran (raquelvergara38@yahoo.com.br) on 2016-04-27T00:00:15Z No. of bitstreams: 1 fabiano de andrade ferreira -filmes nanocompsitos antimicrobianos obtidos - fabiano.pdf: 1339665 bytes, checksum: 6d9b23ae68b29ab5bf3a34d2d80e6ce3 (MD5) / Approved for entry into archive by Gilmar Barros (gilmargomesdebarros@gmail.com) on 2016-04-29T21:16:14Z (GMT) No. of bitstreams: 1 fabiano de andrade ferreira -filmes nanocompsitos antimicrobianos obtidos - fabiano.pdf: 1339665 bytes, checksum: 6d9b23ae68b29ab5bf3a34d2d80e6ce3 (MD5) / Made available in DSpace on 2016-04-29T21:16:14Z (GMT). No. of bitstreams: 1 fabiano de andrade ferreira -filmes nanocompsitos antimicrobianos obtidos - fabiano.pdf: 1339665 bytes, checksum: 6d9b23ae68b29ab5bf3a34d2d80e6ce3 (MD5) Previous issue date: 2014 / As indústrias de alimentos, entre elas a indústria pesqueira, geram uma grande quantidade de resíduos que, quando descartados de maneira inadequada, podem causar sérios problemas para o meio ambiente. O objetivo deste trabalho foi desenvolver e avaliar filmes antimicrobianos nanocompósitos, de proteínas recuperadas da carne mecanicamente separada de pescado de baixo valor comercial, incorporados com óleos essenciais. Para este fim, utilizou-se proteína recuperada da corvina (Micropogonias furnieri), glicerol, montmorilonita e óleos essenciais de orégano e cravo. A proteína recuperada foi caracterizada quanto a sua composição proximal e funcionalidade apresentando um conteúdo proteico de 94,62% em base seca. Na obtenção dos filmes utilizou-se a técnica de casting onde forma realizados vários experimentos variando a composição da solução filmogênica em relação à quantidade de proteína, glicerol, nanoargila montmorilonita e óleos essenciais de orégano e de cravo. Os filmes foram caracterizados em relação à opacidade, solubilidade em água, propriedades mecânicas e permeabilidade ao vapor de água, sendo selecionados os filmes incorporados com óleos essenciais que apresentaram os melhores resultados, enfatizando-se a característica de elongação. A atividade antimicrobiana dos filmes, em relação à Escherichia coli, Staphylococcus coagulase positiva e Salmonella Enteretidis, foi verificada pelo método de difusão em disco. Os filmes incorporados com óleos essenciais na concentração mínima de 1 mL foram os que desenvolveram atividade antimicrobiana em relação aos microrganismos avaliados. As soluções filmogênicas destes filmes foram utilizadas como revestimento através da técnica dipping para avaliar as mudanças ocorridas em camarões branco (Litopenaeus vannamei) crus, descascados e refrigerados a 4±1°C durante 10 dias. Foram avaliadas características como perda de massa, cor, firmeza, pH, N-BVT, TBARS e crescimento microbiológico sendo que, em todos os tratamentos, onde os camarões foram revestidos com as soluções que continham óleo essencial os resultados foram melhores do que o tratamento controle onde a solução não era incorporada de óleo essencial. Neste aspecto o tratamento que continha em sua formulação 4,0 g de proteína recuperada, 1,35 g de glicerol, 0,6 g de montmorilonita, 1,0 mL de óleo essencial de orégano e 1,0 mL de óleo essencial de cravo foi o que apresentou o melhor resultado em todas as características analisadas. O filme correspondente a este tratamento também foi avaliado em relação a sua microestrutura e propriedades térmicas, onde foi verificado que a incorporação dos óleos essenciais altera a superfície do filme deixando-a mais porosa em relação ao filme sem óleos essenciais, por outro lado, a presença de óleos essenciais na estrutura do filme aumentou a estabilidade térmica do mesmo comparando com o filme sem óleos. Os resultados indicam que os filmes incorporados com óleos essenciais de orégano em uma concentração de 1% (v/v) apresentaram ação inibitória em relação aos microrganismos avaliados e que a vida útil dos camarões revestidos com soluções filmogênicas contendo óleos essenciais, em relação aos camarões sem revestimentos, aumentou de 5 para 8 dias. / The food industries, including the fishing industry, generate a lot of waste when disposed of improperly, can cause serious problems for the environment. The aim of this study was to develop and evaluate antimicrobial nanocomposite films from recovered proteins of mechanically separated fish meat of low commercial value, incorporated with essential oils meat. To this end, we used protein recovered croaker (Micropogonias furnieri), glycerol, montmorillonite and essential oils of oregano and clove. The recovered protein was characterized with respect to their composition and function having a protein content of 94.62% on a dry basis. To obtain the films we used the technique of casting where they performed several experiments varying the composition of the film solution for the quantity of protein, glycerol, montmorillonite nanoclay and essential oils of oregano and clove. The films were characterized with respect to opacity, water solubility, mechanical properties and permeability to water vapor, being selected films incorporated with essential oils that showed the best results, emphasizing the characteristic elongation. The antimicrobial activity of the films in relation to Escherichia coli, Staphylococcus coagulase positive and Salmonella Enteretidis was verified by the disk diffusion method. Films incorporated with essential oils at the minimum concentration of 1mL were those who developed antimicrobial activity towards microorganisms evaluated. The film formation solutions of these films were used as coating by dipping technique to evaluate changes in white shrimp (Litopenaeus vannamei) raw, peeled and chilled at 4 ± 1°C for 10 days. Characteristics such as weight loss, color, firmness, pH, TVB-N, TBARS and microbiological growth were being evaluated, in all treatments, where shrimp were coated with solutions containing essential oil were better than treatment control where the solution was not incorporated essential oil. In this respect the treatment that contained in its formulation 4.0 g of recovered protein, 1.35 g glycerol, 0.6 g montmorillonite, 1.0 mL of oregano essential oil and 1.0 mL of clove essential oil showed the best results in all traits. The film corresponding to this treatment was also evaluated for its thermal properties and microstructure, which found that the incorporation of essential oils alters the film surface making it more porous compared to the film without essential oils, on the other hand, presence of essential oils in the structure of the film increased thermal stability compared with the same film without oils. The results indicate that the films incorporated with oregano essential oils in a concentration of 1% (v / v) showed inhibitory activity towards microorganisms evaluated and that the life of shrimp coated film formation solutions containing essential oils in relation to shrimp without coatings increased from 5 to 8 days.

Esta pesquisa tem como objetivo investigar as relações de comunicação em ambientes de fábricas recuperadas e/ou ocupadas, geridas pelos trabalhadores sob o modelo da autogestão. Nossas hipóteses se fundamentam na perspectiva de que a comunicação, assim como o trabalho, tem uma dimensão ontológica, ainda que este ocupe a posição de fundante do ser social. Esta dimensão ontológica faz com que a comunicação seja constitutiva tanto das relações de produção, quanto do próprio processo produtivo. Nosso recorte se faz sobre as fábricas autogestionadas, anteriormente organizadas sob a forma de sociedades de capital (empresas capitalistas). O que nos interessa é verificar como se dão as relações de comunicação em uma situação onde as relações de produção já não ocorrem sob o modelo hierarquizado tradicional de empresas capitalistas, bem como de que forma a comunicação funciona no modelo autogestionado. Além disso, partimos também da perspectiva de que o mundo do trabalho é a principal mediação nos processos comunicacionais, o que inclui a maneira pela qual o sujeito se relaciona com as formas da comunicação em geral (meios, mediações etc.), o que vem sendo demonstrado pelos estudos de Fígaro (2001 e 2008). Assim, esperamos contribuir com os resultados já alcançados, realizando nossa pesquisa em fábricas autogestionadas. Optamos por uma perspectiva multidisciplinar apoiada no materialismo histórico. Isso inclui o estudo das condições objetivas de realização da comunicação e nosso recurso aos estudos em economia política; o estudo da dimensão subjetiva e simbólica e nosso aporte à análise do discurso; assim como à filosofia e teoria de Marx e outros autores que seguem o seu pensamento. / This research aims to investigate the relations of communication in recovered factories environments and / or occupied, managed by workers under the model of self-management. Our hypotheses are based on the view that the communication, and the work has an ontological dimension, even though it occupies the foundational position of social being. This ontological dimension makes the communication is both constitutive relations of production, as the actual production process. Our look is done on the self-managed factories, previously organized in the form of capital companies (capitalist firms). What interests us is to see how to give the relations of communication in a situation where the relations of production do not arise under the traditional hierarchical model of capitalist enterprises, as well as how communication works in the self-managed model. It also set off the prospect that the world of work is the main mediation in communication processes, including the way in which the subject is related to the forms of communication in general (media, mediation etc.), which has being demonstrated by studies of Figaro (2001 and 2008). Thus, we hope to contribute to the results already achieved by conducting our research in self-managed factories. We opted for a multidisciplinary approach supported in historical materialism. This includes the study of objective conditions for implementing the communication and use of our studies in political economy; the study of subjective and symbolic dimension and our contribution to discourse analysis; as well as the philosophy and theory of Marx and others who follow your thinking.