Elastomeric wastes plague our time, polluting our environment and requiring urgent upcycling solutions. This research contributes to this agenda using an important source of waste, car tyre shred fibre residue (TSFR). It is demonstrated how using binders, non-foaming (SBR) and foaming (PU), we can transform these TSFR into structured porous acoustic-thermal insulation materials, suitable as underlay, cavity wall and pipe insulation. These structures were fabricated in purpose designed moulds and characterised for their porosity, tortuosity, flow resistivity and density. Their acoustic absorption performance was measured using industrial standards and the measurement underpinned with the Johnson-Champoux-Allard (JCA) model. With the under-layer materials, thermal insulation was also measured. The results were as follows: (i) 40%/60% SBR/TSFR was an optimal composition for the underlay with the addition of 15% w/w bumper crumb of size > 1mm enhancing both impact sound and thermal insulation, (ii) PU was found to produce well performing wall cavity insulation, particularly when vacuum pressure was applied, allowing micro and macro pores to be formed; (iii) PU applied with controlled amount of water to control foaming CO2 formation produced super-performing (compared with Armacell System B) stratified pipe cladding insulation, optimal at porosity stratification of 90%, 83%, and 70%; (iv) Very good agreement was observed with predictions using JCA model, allowing further research to be carried out with these now well characterised sound insulations. In addition to the developing materials, a novel technique for measuring sound absorption of pipe cladding was developed that could replace the expensive standard using a reverberation chamber.

Les contributions de cette thèse de doctorat sont focalisées sur les développements de formulations à base de polymères bio sourcés et déliantable à l’eau basés sur l’emploi d’acétate butyrate de cellulose (CAB) et de polyéthylène glycol (PEG). Ces nouvelles formulations ont été appliquées sur différentes nuances de poudres métalliques (invar) et céramiques (zircones). Ces matériaux possèdent une bonne stabilité dimensionnelle sous une large gamme de température imposée et possèdent de très bas coefficients d’expansion thermique.L’objective est l’étude et la compréhension du comportement des liants à base de CAB et PEG quand ils sont utilisés dans les variantes du procédé MIP (étapes de moulage avec ou sans pression, conditions particulières liées à la micro-injection, …) réalisées avec différentes nuances de poudres et différentes granulométries.Les caractéristiques intrinsèques de chaque CAB, leurs interactions avec le PEG et les poudres, l’influence de la nuance de poudre employée, ainsi que la granulométrie et la morphologie des poudres employées ont été étudiées et analysées en fonction du comportement final de la formulation développé et des taux de charges obtenues.L’homogénéité des mélanges développés, leurs taux de charge critique et maximal, ainsi que leurs comportements mécaniques, thermiques et rhéologiques ont été analysés et investigués par différentes études mécaniques, thermo et physico-chimiques. De nouvelles analyses chimiques et physiques ont été introduites par accroitre les connaissances sur les formulations développées. Les formulations optimales ont été validées pour différentes applications et avec l’emploi de différentes variantes du procédé MIP conduisant à l’élaboration de composants et de micro-composants PIM obtenus sans défauts et possédant d’excellentes propriétés fonctionnelles. L’étape de déliantage ainsi que l’étape de densification ont été optimisées en termes de cinétique et d’atmosphère aboutissant aux propriétés physiques et mécaniques escomptées pour l’ensemble des nuances de poudres considérées dans cette étude.En conclusion, les formulations développés des liants basées sur l’emploie de CAB et PEG sont exploitable au niveau de la recherche et au niveau industriel dans le procédé MIP. Elles apportent des améliorations par rapport aux liants conventionnels grâce à un procédé plus écologique. Cette première contribution représente une avancée significative dans l’émergence d’un procédé MIP plus écologique mais d’autres travaux futurs sont encore possibles. / This PhD Thesis studied the use of binders based on cellulose acetate butyrate (CAB) andpoly(ethylene glycol) (PEG) in different type of materials, including a ceramic, the zirconiumsilicate, and a metallic alloy, the Invar 36. These materials share their low dimensionalstability with temperature with low coefficients of thermal expansion.The scope of this work is the study and comprehension of the behaviour of the mentionedbinder systems when they are employed in different PIM processes and under differentconditions and powder-types. With regard to this matter, different formulations were designedwith several types of PEG and CAB. These formulations were compared with commercialones. The intrinsic characteristics of each CAB were linked with the behaviour of the differentfeedstock also containing PEG and powder particles. The mixtures homogeneity, the optimumand critical solid loading and its flowability were assessed by torque and capillary rheology.Other complementary techniques such as electronic and light microscopy or the measurementof the mixtures densities by pycnometry were carried out to contrast rheology results. Thecompatibility between the feedstocks’ components and their thermal behaviour were analysedby calorimetry and thermogravimetry techniques. These methods were employed by the firsttime to determine the optimal solid loading.The optimal compositions were injected by using low or high pressures or by a micro injectionmoulding process. The debinding and sintering stages were optimised using severalatmospheres. Finally, the physical and mechanical properties of the final consolidated partswere measured.It could be concluded that the studied binder systems based on PEG and CAB presentedsuitable characteristics for PIM, providing improvements with respect to conventional bindersystems and by a more environmental friendly processing. However, that doctoral work wasjust a first approach to the use of these types of binder systems in PIM. Along this workseveral issues were detected and some topics regarding the processing should be furtherinvestigated to obtain the best of these binder systems.

O presente trabalho tem como objetivo identificar e analisar parâmetros que influenciam a aderência de matrizes cimentícias a substratos apontando soluções técnicas para a melhoria de tal propriedade. Para tanto, foram desenvolvidos três estudos independentes: primeiro, a elaboração e validação de um modelo matemático com base na restrição geométrica para verificar a contribuição da penetração de partículas em meios porosos. O modelo considera que, após serem lançadas sobre a superfície, as partículas com área de projeção no plano menor ou igual à área do poro podem penetrá-la; segundo, um estudo experimental comparando substratos cimentícios com mesmas características topográficas (rugosidade/porosidade) e diferentes níveis de absorção obtidos mediante tratamentos superficiais: aplicação de silano e lixamento para verificar o efeito da absorção do substrato. O controle da absorção foi realizado por medições do ângulo de contato aparente e ensaios de absortividade; e por último, a influência do teor de ligante da matriz foi avaliada pela substituição de 30% e 60% do cimento por finos calcários, com duas distribuições granulométricas, em argamassas aplicadas sobre blocos cerâmicos. O efeito da aglomeração de partículas foi estudado pela adição de dispersante a base de policarboxilato num teor de 0,02% em relação ao volume total de sólidos. As características reológicas das argamassas foram medidas por reometria rotacional. O desempenho mecânico da interface matriz-substrato foi avaliado pela resistência de aderência ä tração. Os resultados mostraram que a aderência depende de parâmetros mais complexos que a simples absorção do substrato e, consequente ancoragem mecânica pela penetração de partículas nos poros. O uso de partículas finas associadas a dispersantes e tratamentos superficiais do substrato aumentaram aderência pelo acréscimo de contato matriz-substrato. / This study aims to identify and analyse parameters that influence the adhesion among cementitious matrices and substrates pointing out technical solutions to improve this property. The research has been developed by means of three independent studies. The first one concerns the development and validation of a mathematical model, based on geometric constraints, for the estimation of the particles potential penetration in porous media. The model considers particles with projected area less than or equal to the pore area can penetrate the pore. The second study is an experimental comparison among cementitious substrates with same porosity and roughness and different levels of absorption achieved by surface treatment. The application of abrasive methods and a water repellent have been used to manage the effect of the absorption of substrates. The control of wettability and absorption has been carried out by measuring the apparent contact angle and sorptivity. The third one regards the evaluation of binders content in cementitious matrices. Mortars, with two different limestone fines, have been made and applied on red ceramic substrates (clay bricks). The limestone fines, with two different particle size distributions, have been added at rates of 30% and 60% as replacement of binders volume. The agglomeration of particles has been assessed adding a polycarboxylate type admixture (0.02% of total solids volume), whereas the rheological behavior have been determined using a rotational rheometer. The performance of interface between matrix and substrate has been determined measuring the tensile adhesive strength. Results showed that the adhesion depends on parameters more complex than the simple absorption of substrate and the consequent mechanical interlocking of particles into pores. The use of fine particles, combined with the dispersant and with the silane surface treatment increased the adhesion through the increase of the contact area.

Este trabalho teve por objetivo o desempenho de misturas asfálticas densas utilizando um ligante convencional (CAP-20) e o mesmo ligante modificado com polímeros tipo SBS, produzido sob o nome comercial de BETUFLEX B 65/60, através dos ensaios Marshall, fluência por compressão uniaxial estática e dinâmica, resistência à tração por compressão diametral e módulo resiliente pro compressão diametral dinâmica, em misturas compactadas com uma mesma faixa granulométrica e diferentes teores de ligantes. O ensaio Marshall apresentou, para as misturas preparadas com asfalto modificado, valores maiores de estabilidade para a maioria dos teores, apesar de valores elevados de fluência em todos os teores analisados. Os resultados de deformação do ensaio de fluência por compressão uniaxial não distinguiram claramente o efeito da adição de polímeros em misturas asfálticas, ao contrário do observado no ensaio dinâmico, onde as deformações foram consideravelmente menores para a maioria dos teores analisados. Os resultados do ensaio de resistência à tração por compressão diametral mostram um desempenho superior da mistura modificada. O ensaio de módulo resiliente por compressão diametral dinâmica indicou, à temperatura de 25ºC, valores menores para a mistura com asfalto modificado, não sendo notada, entretanto, uma diferenciação de desempenho nas temperaturas de 5ºC e 40ºC. A modelação matemática das curvas de fluência e de recuperação às equações constitutivas de alguns modelos visco-elásticos básicos detectou uma diferenciação entre os valores de alguns elementos constitutivos, tanto do ensaio dinâmico, quanto do estático. / The purpose of this study is to evaluate the performance of asphalt mixes using conventional binder and the same binder modified with SBS polymer (Betuflex B 65/60) based on Marshall test, static and dynamic creep tests, indirect tensile strength test and resilient modulus by indirect tensile test, with the same granulometric composition and different binders contents. In Marshall test, polymer modified asphalt mixes presented better stability performance than conventional asphalt mixes in most of binders contents, despite of the higher flow values obtained for all binders contents. The static creep test results indicated that this test does not clearly distinguish the effect of polymer in asphalt mixes while the results of dynamic creep test indicated the opposite, i. e., polymer modified asphalt mixes deformations are smaller for most of the asphalt binders contents studied. The indirect tensile strength test results showed a better performance of modified asphalt. The results of resilient modulus by indirect tensile test at 25°C showed smaller values for modified asphalt, while the results at 5ºC and 40ºC did not show differences between the asphalt mixes. The mathematics modelling of the creep and recovering curves according to constitutive equations of some basic visco- elastic models showed a difference between the values of some constitutive elements in both cases, dynamic and static tests.

A leptospirose é uma zoonose de importância mundial causada por bactérias do gênero Leptospira. No Brasil, a maioria dos casos é causada por L. interrogans sorovar Copenhageni. O objetivo destre trabalho foi identificar adesinas de leptospira pela técnica de Phage display. Bibliotecas com fragmentos genômicos resultaram na idendificação de ligantes de leptospira com afinidade por tecidos de hamster. Uma varredura dessas bibliotecas contra heparan sulfato proteoglicano (HSPG) identificou como ligantes as proteínas LigA e LigB. Proteínas recombinantes foram produzidas e submetidas à ligação às células de mamíferos e aos componentes de matriz extracelular. LigB recombinante foi capaz de se ligar ao HSPG, à heparina e às células de mamíferos. HSPG e heparina foram capazes de reduzir significativamente a interação dessa proteína com as células. Estes resultados evidenciam o papel de proteínas da leptospira na sua interação com o hospedeiro e ilustram a possibilidade do uso da técnica de phage display para identificar possíveis adesinas. / Leptospirosis is a worldwide important zoonosis caused by bacteria of the genus Leptospira. In Brazil, most cases is caused by L. interrogans serovar Copenhageni. Our goal was to identify leptospiras adhesins by phage display technique. Libraries of genomic fragments resulted in the identification of ligands with affinity for leptospiras hamster tissues. Screening these libraries against heparan sulfate proteoglycan (HSPG) identified the proteins LigA and LigB. Recombinant proteins were produced and subjected to binding to mammalian cells and extracellular matrix components. LigB recombinant was able to bind to HSPG, heparin and mammalian cells. HSPG and heparin were able to significantly reduce the interaction of this protein with cells. These results highlight the role of leptospiras proteins in its interaction with the host and illustrate the possibility of the use of phage display technique to identify potential adhesins.

O uso de asfaltos modificados com polímeros tem crescido significativamente nas últimas décadas em função do aumento da densidade de tráfego, da carga por eixo nos veículos e da pressão dos pneus. Estes ligantes proporcionam o aumento a vida útil e a redução do custo de manutenção das rodovias. Os polímeros mais utilizados na modificação de asfalto são os copolímeros em bloco de estireno-butadienoestireno. Esta tese avaliou os efeitos de diferentes agentes compatibilizantes (óleos) e agentes de ligação no comportamento reológico de misturas asfálticas modificadas com copolímeros de estireno-butadieno-estireno, bem como a influência da sua estrutura, se linear ou radial. Para isto foram realizados análises convencionais e testes em reômetro de cisalhamento dinâmico. Os dados obtidos permitiram evidenciar a eficácia do óleo de xisto como agente compatibilizante, proporcionando excelente dispersão do polímero na matriz asfáltica e estabilidade a estocagem a altas temperaturas. Este óleo apresenta-se como uma opção tecnicamente viável para o óleo aromático atualmente em uso no mercado. Foi também verificado que o uso de enxofre como agente de ligação tem um efeito altamente positivo nas propriedades do ligante modificado, com significativa redução da tan ō, da deformação após aplicação de cargas cíclicas e elevação do módulo complexo, o que contribui para obtenção de pavimentos com maior resistência a deformação e ao trincamento por fadiga. / The use of polymer modified asphalts has grown significantly in the last decades due to the increase in traffic density, axle loading in vehicles and tyre pressure. These binders favor the increase of pavement life and the reduction of its maintenancement costs. The most used polymer for asphalt modification is styrene-butadiene-styrene blocked copolymers. This thesis evaluated the effects of different compatibilizers and crosslinkers on rheological behavior of styrene-butadiene-styrene copolymer modified asphalt binders, as well as the influence of its structure, linear or radial. Binder’s characteristics were determined by conventional analysis and tests in dinamic shear rheometer. Data obtained provided evidence of the positive effect of sulfur as crosslinker in modified binders properties, with high tan ō reduction, complex modulus increase and deformation reduction after application of cyclic loads, characteristics that turn possible the existence of pavements with greater rutting and fatigue resistance. It was also verified the shale oil efficacy as a compatibilizer agent, providing an excellent polymer dispersion inside asphalt matrix and a stable storage binder at high temperatures. This oil can be considered as a technical available option to aromatic oil presently in use at pavement industry.

Este trabalho teve por objetivo o desempenho de misturas asfálticas densas utilizando um ligante convencional (CAP-20) e o mesmo ligante modificado com polímeros tipo SBS, produzido sob o nome comercial de BETUFLEX B 65/60, através dos ensaios Marshall, fluência por compressão uniaxial estática e dinâmica, resistência à tração por compressão diametral e módulo resiliente pro compressão diametral dinâmica, em misturas compactadas com uma mesma faixa granulométrica e diferentes teores de ligantes. O ensaio Marshall apresentou, para as misturas preparadas com asfalto modificado, valores maiores de estabilidade para a maioria dos teores, apesar de valores elevados de fluência em todos os teores analisados. Os resultados de deformação do ensaio de fluência por compressão uniaxial não distinguiram claramente o efeito da adição de polímeros em misturas asfálticas, ao contrário do observado no ensaio dinâmico, onde as deformações foram consideravelmente menores para a maioria dos teores analisados. Os resultados do ensaio de resistência à tração por compressão diametral mostram um desempenho superior da mistura modificada. O ensaio de módulo resiliente por compressão diametral dinâmica indicou, à temperatura de 25ºC, valores menores para a mistura com asfalto modificado, não sendo notada, entretanto, uma diferenciação de desempenho nas temperaturas de 5ºC e 40ºC. A modelação matemática das curvas de fluência e de recuperação às equações constitutivas de alguns modelos visco-elásticos básicos detectou uma diferenciação entre os valores de alguns elementos constitutivos, tanto do ensaio dinâmico, quanto do estático. / The purpose of this study is to evaluate the performance of asphalt mixes using conventional binder and the same binder modified with SBS polymer (Betuflex B 65/60) based on Marshall test, static and dynamic creep tests, indirect tensile strength test and resilient modulus by indirect tensile test, with the same granulometric composition and different binders contents. In Marshall test, polymer modified asphalt mixes presented better stability performance than conventional asphalt mixes in most of binders contents, despite of the higher flow values obtained for all binders contents. The static creep test results indicated that this test does not clearly distinguish the effect of polymer in asphalt mixes while the results of dynamic creep test indicated the opposite, i. e., polymer modified asphalt mixes deformations are smaller for most of the asphalt binders contents studied. The indirect tensile strength test results showed a better performance of modified asphalt. The results of resilient modulus by indirect tensile test at 25°C showed smaller values for modified asphalt, while the results at 5ºC and 40ºC did not show differences between the asphalt mixes. The mathematics modelling of the creep and recovering curves according to constitutive equations of some basic visco- elastic models showed a difference between the values of some constitutive elements in both cases, dynamic and static tests.

Rechargeable lithium ion and lithium (Li) metal batteries with high energy density and stability are in high demand for the development of electric vehicles and smart grids. Intensive efforts have been devoted to developing high capacity battery electrodes. However, the known high capacity electrode materials experience fast capacity fading and have limited cycle life due to electromechanical degradations, such as fracture of Si-based electrodes and dendrite growth in Li metal electrodes. A fundamental understanding of electromechanical degradation mechanisms of high capacity electrodes will provide insights into strategies for improving their electrochemical performance. Thus, this dissertation focuses on mechanical properties, microstructure changes, and degradation mechanisms of Si composite electrodes and Li metal electrodes. Based on these findings, possible coping strategies are proposed to improve the cycling stability of both electrodes. The poor cycling life of Si-based electrodes is caused by the repeated lithiation/delithiation-induced huge volumetric change in Si particles, which leads to the fracture of particles, excessive formation of solid electrolyte interphase on the newly exposed surface, as well as the loss of electronic conductivity between Si particles and the conductive matrix. The expansion/contraction of Si particles during cycling also causes the changes in the mechanical properties, microstructure, and porosity of Si composite electrodes. Understanding the relationship between mechanical property evolution, microstructure degradation, and capacity fading is essential for the design of Si composite electrodes. Using an environmental nanoindentation system, in situ microscope cell, and electrochemical impedance spectroscopy, I investigated the mechanical properties, cracking behavior, and lithiation/delithiation kinetics of Si composite electrodes made with different polymeric binders, including polyvinylidene fluoride, Nafion, sodium-carboxymethyl cellulose, and sodium-alginate, in their realistic working environment. The mechanical property evolution is determined by the state-of-charge, porosity, irreversible volume change, and mechanical behavior of binders. Periodical crack opening and closing happens in Si composite electrodes prepared with binders that have strong adhesion with Si. Mechanical degradations, e.g., irreversible volume change, cracking, and debonding between binders and Si particles, are correlated with the evolution of lithiation/delithiation kinetics and the capacity fading of Si composite electrodes. Based on these findings, a partial charging approach is proposed and confirmed experimentally to improve the cycling stability of Si composite electrodes. Li metal electrodes suffer from the low Coulombic efficiency, high electrochemical reactivity with the electrolytes, and the safety hazards caused by the uncontrollable dendrite growth during cycling. Mechanical suppression by using solid electrolytes and artificial SEI is a promising strategy to inhibit the formation of Li dendrites. Mechanical properties of bulk and mossy Li are required for designing mechanical inhibitors and improving the stability of the Li | inhibitor interface. Using an environmental nanoindentation system, I studied the mechanical behavior, especially the time-dependent behavior, of bulk Li and porous mossy Li at ambient temperature. By combining finite element (FE) modeling with experiments, a constitutive law was determined for the viscoplastic deformation of Li metal. FE modeling also demonstrates that the elasticity has a negligible influence on the indentation deformation of bulk Li. Flat punch indentation measurements showed that mossy Li has significantly higher deformation and creep resistance than bulk Li despite of its porous microstructure. The mechanical parameters of bulk and mossy Li may be helpful to develop of dendrite-free Li metal electrodes.

Um bei der Herstellung der Holzpellets den Energieaufwand zu minimieren und gleichzeitig die Qualitätsanforderungen der DINplus zu erfüllen, werden häufig Presshilfsmittel beim Pelletieren eingesetzt, bisher vor allem Mais- und Weizenstärke. Um flexibler auf veränderte Markt- und Rohstoffbedingungen reagieren zu können, besteht von Seiten der Hersteller Bedarf an alternativen Presshilfsmitteln. Allerdings ist deren Einfluss auf das Verbrennungs-, Emissions- und Ascheerweichungsverhalten nur unzureichend erforscht. Im Rahmen eines Forschungsprojektes zur Optimierung der Pelletproduktion wurden in dieser Diplomarbeit Versuche durchgeführt, um den Einfluss verschiedener natürlicher Presshilfsmittel, der Pelletqualität (Feinanteil, Stückigkeit) und der Feuerungsart (Unterschub- und Abwurffeuerung mit Brennerschale) auf das Emissionsverhalten (Kohlenmonoxid-, Stickoxid-, Gesamtkohlenstoff und Staubgehalt im Abgas), den Anlagenbetrieb (Brennstoffförderraten, Abgasverluste, Luftüberschuss) und das Ascheerweichungsverhalten beim Betrieb von zwei Kleinfeuerungsanlagen mit DINplus-konformen Holzpellets, zu untersuchen.

Computer-aided drug discovery involves the application of computer science and programming to solve chemical and biological problems. Specifically, the QSAR (Quantitative Structure Activity Relationships) methodology is used in drug development to provide a rational basis of drug synthesis, rather than a trial and error approach. Molecular dynamics (MD) studies focus on investigating the details of drug-target interactions to elucidate various biophysical characteristics of interest. Infectious diseases like Trypanosoma brucei rhodesiense (TBR) and P. falciparum (malaria) are responsible for millions of deaths annually around the globe. This necessitates an immediate need to design and develop new drugs that efficiently battle these diseases. As a part of the initiatives to improve drug efficacy QSAR studies accomplished the formulation of chemical hypothesis to assist development of drugs against TBR. Results show that CoMSIA 3D QSAR models, with a Pearson’s correlation coefficient of 0.95, predict a compound with meta nitrogens on the phenyl groups, in the combinatorial space based on a biphenyl-furan diamidine design template, to have higher activity against TBR relative to the existing compound set within the same space. Molecular dynamics study, conducted on a linear benzimidazole-biphenyl diamidine that has non-classical structural similarity to earlier known paradigms of minor groove binders, gave insights into the unique water mediated interactions between the DNA minor groove and this ligand. Earlier experiments suggested the interfacial water molecules near the terminal ends of the ligand to be responsible for the exceptianlly high binding constant of the ligand. Results from MD studies show two other modes of binding. The first conformation has a single water molecule with a residency time of 6ns (average) that is closer to the central part of the ligand, which stabilizes the structure in addition to the terminal water. The second conformation that was detected had the ligand completely away from the floor of the minor groove, and hydrogen bonded to the sugar oxygens.