Les principaux objectifs de ces travaux de thèse sont d'une part d'optimiser le protocole d'élaboration des barrières thermiques (BT) issues de la voie sol-gel et d'autre part de caractériser l'adhérence de ces barrières thermiques mais aussi de proposer des pistes en vue d'augmenter la durée de vie de celles-ci. Tout d'abord, une première étude a porté sur le choix et la validation d'un nouvel agent dispersant pour optimiser la formulation du sol chargé permettant la mise en forme des barrières thermiques. Ainsi, ce changement de dispersant a généré une microstructure conduisant à une augmentation significative de la durée de vie du système en oxydation cyclique mais a aussi permis de simplifier le protocole d'élaboration puisque l'étape de colmatage, jusqu'alors nécessaire, a été supprimée. L'étude paramétrique de la microstructure surfacique des barrières thermiques a montré que le réseau de microfissures formé initialement restait stable en fonction du vieillissement avec la création d'un sous-réseau microfissuré. Pour comprendre les mécanismes d'endommagement des barrières thermiques sol-gel et les confronter à ceux des barrières thermiques industrielles EB-PVD, la méthode d'indentation interfaciale a été retenue pour sonder l'interface revêtement/substrat. Ainsi des valeurs de ténacités apparentes ont pu être déterminées afin de comparer les adhérences des BTSG et des BTEB-PVD. A partir de ces résultats, des modèles phénoménologiques d'endommagement ont été imaginés. Pour les BTEB-PVD, l'initiation et la propagation de fissures restent localisées à l'interface barrière thermique/sous-couche de liaison, d'un coté ou de l'autre de l'oxyde de croissance selon les conditions, alors que pour les BTSG, l'endommagement est induit par la libération d'énergie élastique stockée dans le système qui augmente en fonction du vieillissement. / The main objectives of this PhD are first to improve and optimise the elaboration protocol of thermal barrier coatings (TBC) manufactured by the sol-gel route and then to characterise their adhesion and investigate the possibility to enhance their lifetime. A preliminary study is focused on the selection and validation of a new dispersing agent to optimise the composite sol formulation before shaping TBC. Indeed, the new dispersant induced a microstructure allowing to significantly increase the cyclic oxidation lifetime of the system but also to simplify the elaboration process as the reinforcement step was suppressed. The parametric study of TBC surface microstructure proved that the initial micro-cracks network remained stable during ageing including the formation of a crack sub-network. To understand the damage mechanisms of sol-gel TBC and to compare them to those corresponding to industrial EB-PVD TBC, the method of interfacial indentation was developed to investigate the subtrate/top-coat interface. The apparent toughness values were determined to compare both BTSG and BTEB-PVD adhesions. From these results, phenomenological models for damage mechanisms were proposed. For BTEB-PVD, crack initiation and propagation are located at the top-coat/bond-coat interface, either on one side or the other side of the thermally grown oxide (TGO) depending of the conditions. For BTSG, the damage is a consequence of the release of the elastic strain energy stored in the system, increasing with the ageing temperature.

La pomme (Malus Domestica Borkh.), fruit largement répandu dans les pays tempérés est beaucoup consommée. Elle représente une source importante en composés phénoliques. Cette étude s’est intéressée aux polyphénols des tissus du parenchyme. La problématique s’oriente sur les effets de la texture sur la diffusion de ces molécules. L’originalité de l’approche repose sur l’association de la texture, de la pression osmotique et la diffusion des polyphénols. Les méthodes de caractérisations physiques et biochimiques ont permis de mesurer les changements à l´échelle macroscopique et les modifications chimiques qui s’opèrent dans les matrices végétales. Les résultats de l’étude du transfert de matière ont permis de mettre en évidence les différents facteurs pouvant influer sur les valeurs des coefficients de diffusion. La texture, l’épaisseur, la variété du fruit et la pression du milieu diffusant, constituent des facteurs pouvant influencer le transfert de matière. L’étude de l’évolution de composant de la paroi a montré des changements qui s’opèrent au cours de la diffusion. Des analyses microscopiques ont relevé les modifications à l’échelle cellulaire de la diffusion de procyanidines, polyphénols majoritaires et des interactions avec les composants pariétaux. / Apple (Malus domestica Borkh. ) fruit widespread in temperate countries, is much consumed.It represents an important source of phenolic compounds. This study was interestedin polyphenol content of apple tissue parenchyma. The problem concerns effects of texturedegradation on the diffusion of polyphenols molecules. The originality of the approach isbased on the combination of texture, osmotic pressure and polyphenol leaching. Physicaland biochemical methods were used to measure changes at macroscopic scale and chemicalchanges occurring in the parenchymateous tissue . The study of mass transfer highlightedvarious factors that may affect apparent coefficient diffusion. The result showed that thedisintegration of texture , thickness, apple variety and osmotic pressure of leaching mediacan influence mass transfer yield. The study of the Cell walls components showed changesthat occur during leaching process. Light microscopic analysis revealed changes at cellularscale, procyanidins the major polyphenols, leaching phenomena and also interactionswith cell walls matrix.

Fundação de Apoio a Pesquisa e à Inovação Tecnológica do Estado de Sergipe - FAPITEC/SE / The author of the present work aimed at evaluating the influence of the inclusion of soybean hull (SH) upon the apparent digestibility, the physical-chemical characteristics of feces and the postprandial glycemic responses of horses submitted to moderate-intensity exercise. Five horses were used, aging 11 +2 years old and weighing 483 ± 18 kg. The diets consisted of 60% of Tifton 85 hay (Cynodon spp) and 40% of a pelletized commercial concentrate. The treatments were: substitution of the concentrate for 0%, 10%, 20%, 30% and 40% of SH (Kg/Kg). The experimental period lasted 50 days, being 5 ten-day periods: 7 days for the adaptation to the diet and 3 days of total feces collection. Bromatological analyses of both the foods and of the feces samples were performed for the determination of the apparent digestibility coefficients of the nutrients. The evaluation of the characteristics of the feces comprehended consistency, coloration and pH. For the glycemic tests, 5 mL of blood was collected around 30 minutes before, and 30, 60, 90, 120, 180, 240 and 300 minutes after the administration of the soybean hull homogenized to the concentrate. The experimental delineation used was entirely casualized in Latin square (5x5). For the statistical analyses, the data were submitted to variance analysis. The means were compared with Tukey´s test at 5% of significance. The result demonstrated that there were no effects (P>0.05) of the substitution levels of the concentrate for the soybean hull over the apparent digestibility coefficient of dry matter, organic matter, crude protein, ether extract, nonstructural carbohydrates, hemicellulose, rapidly fermented carbohydrate and energy. However, significant statistical differences were observed (P<0.05) for the apparent digestibility coefficient acid detergent fiber and slowly fermented carbohydrate, with better results for the 30% and 40% substitution levels and a drop in hydrolysable carbohydrate at the 40% level of substitution. Regarding the consistency and coloration, 100% of the horses produced normal (score 3) green-colored feces. There were no statistical differences for the pH value, with means of 6.34. The glucose peak and the area below the glycemic curve were not influenced (P<0.05) by the increasing levels of soybean hull in the diet. It is concluded that the soybean hull can be replaced in 30% and 40%, thus allowing the increase in the apparent digestibility of the fibrous fraction, without causing alterations to the physical-chemical characteristics of both the feces and the glycemic responses of horses undergoing moderate-intensity exercises. / O objetivo da autora deste trabalho foi avaliar a influência da inclusão de casca de soja (CS) na digestibilidade aparente, características físico-químicas das fezes e resposta glicêmicas pós-prandial de equinos submetidos a exercício de intensidade moderada. Foram utilizados cinco equinos com idade de 11 +2 anos e peso médio de 455 ± 23 kg. Os tratamentos foram: substituição do concentrado por 0%, 10%, 20%, 30% e 40% de CS (Kg/Kg). O período experimental teve duração de 50 dias, divididos em cinco períodos de 10 dias cada, sendo 7 dias de adaptação à dieta e 3 dias de coleta total de fezes. Realizou-se análises bromatológicas dos alimentos e das amostras compostas de fezes para estimar os coeficientes de digestibilidade aparente dos nutrientes. As avaliações das características das fezes compreenderam consistência, coloração e pH. Para o teste glicêmico foram coletados 5 mL de sangue cerca de 30 minutos antes, 30, 60, 90, 120, 180, 240 e 300 minutos após administração da casca de soja homogeneizada ao concentrado. O delineamento experimental foi inteiramente casualizado em quadrado latino (5x5). Os dados foram submetidos à analise de variância e as médias comparadas pelo teste Tukey a 5% de significância. Os resultados demostraram que não houve efeitos (P>0,05) dos níveis de substituições do concentrado pela casca de soja sobre os coeficientes de digestibilidade aparente da matéria seca, matéria orgânica, proteína bruta, extrato etéreo, carboidratos não estruturais, hemicelulose, energia bruta e carboidratos rapidamente fermentáveis; porém, observaram-se diferenças estatísticas significativas (P<0,05) para os coeficientes de digestibilidade aparente da fibra em detergente ácido e carboidratos lentamente fermentáveis, com aumento para os níveis de 30% e 40% de substituição e queda no coeficiente de digestibilidade aparente dos carboidratos hidrolisáveis ao nível de 40% de substituição Quanto à consistência e coloração, 100% dos equinos apresentaram fezes normal (escore 3) e esverdeada. Não houve diferenças estatísticas para o valor de pH com média de 6,34. O pico de glicose, tempo de pico e área abaixo da curva glicêmica não foram influenciados (P<0,05) pelos níveis crescentes de casca de soja na dieta. Conclui-se que a casca de soja pode ser substituída em 30% e 40% proporcionando aumento na digestibilidade aparente da fração fibrosa, sem causar alterações nas características físico-químicas das fezes e nas respostas glicêmicas de equinos submetidos a exercício moderado.

Made available in DSpace on 2016-05-02T13:55:28Z (GMT). No. of bitstreams: 1 DanieliPerezFernandes-Dissertacao.pdf: 233120 bytes, checksum: b36de1201a14f62deb25bd103ba493b6 (MD5) Previous issue date: 2010-11-09 / The objective was to evaluate this work through the intake and digestibility of linseed meal for sheep. A total of 12 female mongrel with body weight (BW) 30 kg were housed in cages for study of metabolism in the experimental period of 40 days (15 days for animal adaptation to experimental diets and 5 days for data collection in each phase). We used a randomized block design, to evaluate four diets (corn silage exclusively - SM, SM + concentrate; SM + concentrate + 5% linseed meal - FL, MS + concentrate + 10% FL) with three replications in two phases. A higher apparent digestibility of dry matter (DM) for calves fed concentrate diets, regardless of the proportion of linseed meal. The same effect was observed in the consumption of crude and digestible nutrients in kg / day, yet the inclusion of 10% linseed meal to the diet caused a decrease in consumption of about 138 g / day (gross nutrients) and 105 g / day ( digestible nutrients) compared to diet without linseed meal (0%). These results were very similar when expressed as% of BW and metabolic size (UTM (g/w0, 75). Inclusion of concentrate to the diet increases the digestibility of nutrients without detrimental effect of higher amount of linseed meal, However, this carries a slight decrease in DM. Therefore, we recommend using the diets containing concentrate and linseed meal in the proportions of 0 and 5%. / Objetivou-se por meio deste trabalho avaliar o consumo e digestibilidade do farelo de linhaça para ovinos. Foram utilizadas 12 fêmeas consideradas puras por cruzamento, com peso vivo (PV) médio de 30 kg, alojadas em gaiolas para estudo de metabolismo no período experimental de 40 dias (15 dias de adaptação e cinco para colheita de dados em cada fase experimental). Utilizou-se o delineamento em blocos ao acaso, avaliando-se quatro dietas (silagem de milho exclusiva - SM; SM + concentrado; SM + concentrado + 5% de farelo de linhaça - FL; SM + concentrado +10% de FL), com três repetições em duas fases. Verificou-se maior digestibilidade aparente da matéria seca (MS) para animais alimentados com dietas contendo concentrado, independente da proporção de farelo de linhaça. O mesmo efeito foi verificado no consumo de nutrientes brutos e digestíveis em kg/dia, contudo a inclusão de 10% de farelo de linhaça à dieta provocou decréscimo no consumo da ordem de 138 (nutrientes brutos) e 105 g/dia (nutrientes digestíveis) quando comparado à dieta sem farelo de linhaça (0%). Estes resultados se mantiveram muito similares quando expressos em % do PV e unidade de tamanho metabólico - UTM (g/kg0,75). A inclusão de concentrado à dieta aumenta a digestibilidade dos nutrientes, sem efeito deletério do maior nível de farelo de linhaça, contudo, este exerce uma pequena queda no consumo de MS. Portanto, recomenda-se utilizar as dietas contendo concentrado e farelo de linhaça nas proporções de 0 e 5%.

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No description available.

In the Arabic-speaking world, sociopolitical upheaval, extended conflict and population displacement have triggered extensive contact between mutually intelligible varieties of the language. Notwithstanding these developments, Arabic sociolinguistic research on dialect contact settings remains limited to certain well-documented areas (e.g., Al-Wer 2020), with markedly less research targeting other locales believed to be highly propitious to convergent change, such as the long-term contact situation in Lebanon involving Lebanese and Palestinian Arabic (Fityan 1981; Hennessey 2011). Furthermore, few studies are embedded in a (comparative) variationist sociolinguistic framework (Owens 2013), and even fewer studies are articulated from a socio-historical perspective incorporating diachronic data sources with which to better understand the process of language change in Arabic (Owens 2013). Much previous research on Arabic dialects is also based on investigations of phonological variation (Al-Wer and de Jong 2018), with correspondingly less attention paid to (morpho-)syntactic variation (Choueiri 2019). The present study aims to address existing lacunae in the research literature by investigating the outcomes of dialect contact in Beirut between Palestinian Arabic (PA), the minority variety, and Lebanese Arabic (LA), the majority variety. Drawing on the framework of comparative variationist sociolinguistics (Poplack and Tagliamonte 2001) as well as research on dialect contact (Britain and Trudgill 2005), this study combines synchronic and diachronic data sources to compare three variables in LA and PA: a phonological variable, involving the word-medial raising of /a:/ to [e:] (e.g., [ka:n] alternating with [ke:n] 'he/it was'); and two morpho-syntactic variables: verbal negation and future temporal reference. The overarching aim of the research is to examine the extent to which PA shows evidence, as gauged from linguistic constraints on variant selection and variant repertoires, of becoming more structurally similar to LA in different linguistic components (Cheshire, Kerswill, and Williams 2005). The synchronic data come from 45 hours of spontaneous speech recorded in Beirut from 39 Palestinian and 27 Lebanese speakers stratified by age, sex, and level of education, generating 7,671 tokens representing the three targeted variables. A further 15,381 tokens of these three variables come from two diachronic datasets. The first is a sub-set of speech recordings from the Palestinian Oral History Archive, an online compendium of interviews with first-generation (older) Palestinians in Lebanon, recorded between the 1990s and early 2000s. The second diachronic dataset is the Lebanese Popular Theatre Corpus (LPTC), based on 34 televised plays dating from the 1960s and performed in colloquial LA. Results reveal that the [e:] variant, a stereotypical feature of LA, but not emblematic of PA spoken in Beirut (Hennessey 2011), is virtually absent from the speech of the older Palestinian generation in the synchronic and diachronic datasets, but it increases significantly in the speech of young (third-generation) Palestinian speakers, who replicate the linguistic conditioning of variant selection in LA. These results bolster the inference of contact-induced change in PA due to the influence of LA. With respect to verbal negation, the findings show that there is convergent change in terms of overall variant rates in this variable system in PA. Evidence suggests that this variable system is undergoing dialect levelling as a result of contact, with socially marked minority variants diminishing over time in the speech of educated Palestinians. The future temporal reference system, however, seems to be less amenable to contact-induced change, despite similarities in surface forms between LA and PA. Results indicate that this variable system is undergoing an internal change in PA independent of contact with LA, which is led by young, educated speakers, in line with what has been observed in PA spoken outside Lebanon (AbuAmsha 2016). Viewed in the aggregate, the results show that even though it is claimed that (morpho-) syntactic variables may be less susceptible to convergent change than phonological variables (Cheshire et al. 2005; Hinskens et al. 2005), we do not find a neat division between phonology and morpho-syntax. Word-medial imala is overtly commented on and explicitly identified by the targeted Palestinian speech community as a marker of Lebanese speech. Its iconic association with Lebanese speech patterns renders it particularly susceptible to long-term dialect accommodation for some Palestinians. Verbal negation is also subject to social evaluation, as gauged from explicit speaker meta-commentary, and socially marked exponents appear vulnerable to attrition over time. By contrast, the expression of the future temporal reference appears less socially indexical than the other variables and is not subject to normative commentary or overt correction. These differences implicate the social salience of the targeted variables as a key factor influencing their susceptibility to convergence. Situating the results in a wider perspective, the findings highlight the utility of the comparative variationist framework in elucidating the process of language change in spoken Arabic, especially in PA as spoken in Beirut, as well as in distinguishing contact-induced change from internally-motivated change. The results of this study indicate that the effects of dialect contact, and critically, the existence of contact-induced change cannot be fully understood without using a multi-faceted comparative approach incorporating horizontal and vertical comparisons. The results converge in demonstrating that an empirically accountable quantitative approach based on actual speech data is capable of transcending the limitations of alternative frameworks of analysis that have been used to investigate change in dialect contact scenarios in the Arabic-speaking world.

This paper reports a numerical approach for modelling the thermal behavior and heat accumulation/liberation of sustainable cementitious composites made with Recycled Brick Aggregates (RBAs) employed as carriers for Phase-Change Materials (PCMs). In the framework of the further development of the fixed grid modelling method, classically employed for solving the well-known Stefan problem, an enthalpy-based approach and an apparent calorific capacity method have been proposed and validated. More specifically, the results of an experimental program, following an advanced incorporation and immobilization technique, developed at the Institut für Werkstoffe im Bauwesen for investigating the thermal responses of various combinations of PCM-RBAs, have been considered as the benchmark to calibrate/validate the numerical results. Promising numerical results have been obtained, and temperature simulations showed good agreement with the experimental data of the analyzed mixtures.

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No description available.