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Yes / This paper presented a new circular polarization reconfigurable antenna for 5G wireless communications. The antenna, containing a semicircular slot, was compact in size and had a good axial ratio and frequency response. Two PIN diode switches controlled the reconfiguration for both the right-hand and left-hand circular polarization. Reconfigurable orthogonal polarizations were achieved by changing the states of the two PIN diode switches, and the reflection coefficient |S11| was maintained, which is a strong benefit of this design. The proposed polarization-reconfigurable antenna was modeled using the Computer Simulation Technology (CST) software. It had a 3.4 GHz resonance frequency in both states of reconfiguration, with a good axial ratio below 1.8 dB, and good gain of 4.8 dBic for both modes of operation. The proposed microstrip antenna was fabricated on an FR-4 substrate with a loss tangent of 0.02, and relative dielectric constant of 4.3. The radiating layer had a maximum size of 18.3 18.3 mm2, with 50 W coaxial probe feeding. / European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424.

Effective treatment of carbon fiber components to improve delamination resistance is vital to the application of such materials since delamination is one of the biggest concerns regarding the use of composites in the aerospace sector. Due to the significant application benefit gained from increased stiffness to density ratio with composite materials, innovative developments resulting in improved through-thickness strength have been on the rise. The inherent anisotropy of composite materials results in an added difficulty in designing structural elements that make use of such materials. Proposed techniques to improve the through-thickness strength of laminar composites are many and varied; however all share the common goal of improving inter-laminar bond strength. This research makes use of novel materials in the field of wet flocking and Z-pinning. Cellulose nanofibers (CNFs) have already demonstrated excellent mechanical properties in terms of stiffness and strength, originating at the nano-scale. These materials were introduced into the laminate while in a sol-gel suspension in an effort to improve load transfer between laminate layers. The effect of CNFs as lightweight renewable reinforcement for CFRPs will be investigated. Carbon nanotube (CNT) additives were also considered for their beneficial structural properties. / Master of Science

The transport of particulates within both a fully developed and developing pin fin arrays is explored using computational fluid dynamics (CFD) simulations. The simulations are carried out using the LES solver, GenIDLEST, for the fluid (carrier) phase and a Langragian approach for the particle (dispersed) phase. A grid independency study and validation case versus relevant experiments are given to lend confidence to the numerical simulations. Various Stokes numbers (0.78, 3.1 and 19.5) are explored as well as three nondimensional particle softening temperatures (θ_ST = 0, 0.37 and 0.67). The deposition is shown to increase with decreasing particle Stokes number and thus decreasing size from 0.005% for St_p = 19.5 to 13.4% for St_p = 0.78 and is almost completely concentrated on the channel walls (99.6% - 100%). The erosion potential is shown to increase with Stokes number and is highest on the pin faces. As is to be expected, the deposition increases with decreasing softening temperature from 13.4% at θ_ST = 0.67 to 79% for θ_ST =0. Overall, the channel walls of the array show the greatest potential for deposition. On the other hand, the pin faces show the greatest potential for erosion. Similarly, the higher Stokes number particles have more erosion potential while the lower Stokes number particles have a higher potential for erosion. / Master of Science

Les champignons ectomycorhiziens forment des symbioses racinaires avec des arbres des forêts boréales. Malgré leur importance dans cet écosystème, leurs exigences en matière d’habitat demeurent mal connues. Deux champignons comestibles, une chanterelle (Cantharellus cibarius var. roseocanus Redhead, Norvell & Danell) et la dermatose des russules (Hypomyces lactifluorum (Schwein.) Tul. & C.Tul. / Russula brevipes Peck.), ont été étudiés dans cette thèse. Trois expériences ont été menées en peuplements aménagés et non aménagés de pin gris (Pinus banksiana Lamb.). Cette étude visait à caractériser les paramètres environnementaux qui influencent la production de carpophores chez ces champignons, à déterminer l’impact d’une peturbation forestière sur ces derniers et à préciser l’importance de la phénologie du pin gris pour la fructification de C. cibarius var. roseocanus. Les résultats relient la distribution (présence/absence des carpophores) et la productivité (biomasse fraîche et densité des carpophores) de ces champignons à des paramètres du sol, du peuplement, de la végétation et du climat. L’aménagement de sentiers n’a pas augmenté la production de carpophores de dermatose des russules, mais l’a maintenu durant les périodes de faibles précipitations. La productivité de ce champignon présente des corrélations positives avec l’abondance de plantes intolérantes à l’ombre et l’ammonium extractible et négatives avec le pH du sol. La productivité de C. cibarius var. roseocanus s’équivaut entre le peuplement aménagé et non aménagé malgré l’absence de carpophores dans les sentiers du peuplement aménagé. L’association végétale Solidago puberula – Comptonia peregrina – Pinus banksiana et la présence de mousses représente un habitat propice à la fructification de cette chanterelle, alors que la présence de plantes éricacées la défavoriserait. Les précipitations et la température de l’air ont aussi un impact sur la quantité de carpophores. Le pic de fructification de C. cibarius var. roseocanus suit la transition du bois juvénile vers le bois mature. Durant la saison de croissance, la respiration du carpophore est synchronisée avec la respiration totale du sol et ces deux respirations sont corrélées avec les variations de températures du sol. Les résultats permettront de mieux prédire la distribution et la productivité de ces espèces en peuplements de pin gris. Ces connaissances contribueront au développement et à l’exploitation durable de cette ressource. / Ectomycorrhizal fungi form root symbioses with boreal tree species. Despite their importance in that ecosystem, their requirements in term of habitat remain unknown. Two edible mushrooms, a chanterelle (Cantharellus cibarius var. roseocanus Redhead, Norvell & Danell) and the lobster mushroom (Hypomyces lactifluorum (Schwein.) Tul. & C.Tul. / Russula brevipes Peck.) were studied in this thesis. Three experiments were conducted in managed and unmanaged jack pine (Pinus banksiana Lamb.) stands. This research aimed to characterize the ecological parameters related to the production of sporocarps of these fungi, to determine the impact of a specific forest disturbance on the latter and to specify the importance of jack pine phenology on the pattern of C. cibarius var. roseocanus carpophore production. Results allowed us to link the mushroom distribution (sporocarp presence/absence) and the productivity (fresh sporocarp biomass and sporocarp density) to specific soil, stand, plant and meteorological parameters. Trail management did not increase lobster mushroom carpophore production but maintained it during periods of reduced precipitation. Productivity of this fungus was positively related to the abundance of shade-intolerant plant species and to extractable ammonium concentration, and negatively related to soil pH. C. cibarius var. roseocanus sporocarp productivity was similar for the managed and the unmanaged stands despite the absence of carpophore on trails of the managed stand. The Solidago puberula – Comptonia peregrina– Pinus banksiana association and mosses presence indicated high-quality environments for chanterelle fructification, whereas ericaceous species presence restricted it. Rainfall and air temperature also had an impact on the carpophore productivity. The C. cibarius var. roseocanus fructification peak followed the earlywood–latewood transition within days. Over the growing season the carpophore respiration was in synchrony with the total soil respiration and these respirations were correlated to the soil temperature patterns. Results will enable the prediction of the distribution and the productivity of these species in jack pine stands. This knowledge will contribute to the sustainable development and use of this natural resource.

L’apport de biosolides mixtes de papetières (BP) aux sols agricoles permet d’assurer l'approvisionnement en nutriments et d’améliorer les propriétés chimiques et biologiques du sol. Toutefois, l’acidification du sol, la mobilité des métaux et le lessivage des nutriments peuvent représenter un défi lorsque les BP sont appliqués sur les sols agricoles. Pour sa part, le biochar influence positivement le pH du sol et la rétention des nutriments et des métaux lourds, ce qui permet de prévenir le lessivage de certains nutriments et ainsi améliorer l’efficacité d’utilisation des fertilisants. La co-application de ces deux amendements sur les sols agricoles du Quebec a fait l’objet de peu d’etudes et pourrait représenter une option très intéressante pour améliorer leur efficacité agronomique. L’objectif de cette thèse était de déterminer comment la co-application des BP et du biochar de pin (Pinus strobus L.) affecte les propriétés chimiques et biologiques de deux sols agricoles. Spécifiquement, cette thèse a évalué l’effet de l’amendement de deux sols acides agricoles (argile et loam sablonneux) avec deux types de BP, variant par le rapport carbone (C)/azote (N) (BP1, C/N=24 et BP2, C/N=13) et le pH (BP1, pH = 7,80 et BP2, pH = 4,51), combinés chacun avec trois taux d’application (0%, 2,5% et 5% poids/poids) de biochar de pin produit à 700 °C. Une incubation a été réalisée dans des conditions contrôlées pendant 224 jours à 25 ºC en utilisant un dispositif en blocs complets aléatoires avec trois répétitions. Les résultats ont démontré que la co-application des BP et du biochar de pin a augmenté le pH du sol, l’activité et la biomasse microbienne et les concentrations de C total et du potassium (K) disponible et a diminué les concentrations de N minéral, et de cuivre (Cu) et de fer (Fe) disponible comparativement à l’application de BP uniquement. L’effet de la co-application des BP et du biochar de pin a été influencé par le taux de biochar, le type de BP et le temps d’incubation. Cette thèse a démontré que la co-application des BP et du biochar de pin s’avère plus bénéfique pour les sols agricoles qu’une application des BP seuls. Elle permet notamment l’augmentation de la matière organique, l’apport plus important en éléments nutritifs, l’amélioration de la rétention des ions nitrate, la prévention de la libération/désorption des métaux lourds en augmentant le pH du sol et l’amélioration du potentiel de recyclage des nutriments en favorisant l’activité et la biomasse microbienne du sol. / Paper mill biosolids (PB) supply plant nutrients and improve soil chemical and biological properties. However, soil acidification, metal mobility and nutrient leaching may present challenges in soil receiving PB. The application of biochar can increase soil pH and nutrient and metal retention, which helps prevent metal toxicity and nutrient leaching and improves the efficient fertilizer use. To our knowledge, the effect of co-applying PB and biochar on the properties of Quebec agricultural soils has not yet been evaluated and could be an interesting way to improve their agronomic efficiency. The objective of this thesis was to determine how co-applying PB and biochar affects soil chemical and biological properties. Specifically, this thesis evaluated the effect of amending two acidic soils, a clay and sandy loam, with two PB types varying in carbon (C)/nitrogen (N) ratio (PB1, C/N=24; and PB2, C/N=13) and pH (PB1, pH = 7.80; and PB2, pH = 4.51) co-applied with three rates (0%, 2.5%, and 5% w/w) of pine (Pinus strobus L.) biochar produced at 700 °C. A 224 days microcosm incubation study was conducted under controlled conditions at 25°C, using a randomized complete block design with three replicates. The results showed that the co-application of biochar and PB increased soil pH, microbial activity and biomass, and total C and available potassium (K) concentrations, and decreased mineral N, and available copper (Cu) and iron (Fe) concentrations compared to the application of PB only. The effect of the co-application of biochar and PB depended on biochar rate, PB type, and incubation time. This thesis showed that co-applying biochar and PB can be more beneficial to agricultural soils than application of PB alone by increasing organic matter, supplying nutrients, improving NO3-N retention, preventing metal toxicity by raising pH and improving the potential of nutrient cycling by promoting microbial activity and biomass.

S'appuyant sur les paradoxes traditionnels que la théologie définissait à partir d'une essence angélique, le XXe siècle poétique éprouve une fascination universelle pour l'ange. Cet engouement apparaît d'autant plus curieux qu'il s'exerce sur l'ensemble des sensibilités poétiques. En outre, ces usages apparaissent si divers et si contradictoires que l'apparition angélique acquiert la propriété radicalement originale de pouvoir supporter indifféremment toute intention d'auteur, et celle plus curieuse encore d'échapper aux intentions premières d'un poète pour développer un sous-discours indépendant. L'ange marque un régime de discours par lequel les différentes instances du discours poétique coexistent dans une relation encore indivisée ; le messager angélique désigne très précisément l'instant où le chaos intime d'un sujet se métamorphose en langage articulé. Cette exploration du phénomène angélique est divisée en trois étapes, consacrées chacune à un corpus différent. L'étude de l'ange comme figure explore les nombreuses variations d'une apparition à l'autre, motivées par des hésitations d'ordre religieux, temporel, civilisationnel, politique et esthétique dans les œuvres de Guillaume Apollinaire pour le domaine français, et d'Odysseus Elytis pour le domaine grec. L'analyse de l'ange en tant que support d'une relation intime du sujet à lui-même interroge de façon plus large les expériences poétiques austro-allemande d'une part, mexicaine d'autre part. Sont enfin envisagées dans le domaine français deux tentatives de constitution d'un langage angélique en poésie, à travers les œuvres majeures de Patrice de La Tour du Pin et de Christian Gabriel/le Guez-Ricord. / Relying on traditional paradoxes that theology defined from an angelic essence, the poetry of the twentieth century expresses a universal fascination towards angels. This attraction appears all the more curious as it applies to all observable poetic sensibilities. In addition, these practices turn out to be so diverse and contradictory that angelic appearance acquire a radically original property to withstand any intention of the author, and the even more curious one to escape the immediate intentions of a poet, developing a secondary speech of its own. The angel marks a way of speech in which different instances of poetic discourse coexist in a still unindividuated relation. The angelic messenger indicates the precise moment when the inner chaos of a subject is transformed into articulate language . This exploration of the angelic phenomenon will be divided into three steps, each dedicated to a different corpus. The study of the angel as a visual figure will explore the many variations from an apparition to another, motivated by hesitations of religious, temporal, civilizational, political and aesthetic kind, as they appear in the poetic works of Guillaume Apollinaire for the French literature, and those of Odysseus Elytis in the Greek linguistic area. The analysis of the angel as a support of an intimate relationship of the subject to itself more broadly interrogate the Austro-German poetic experiences on the one hand, the Mexican on the other hand. Eventually, two attempts to form an angelic language in French poetry will be considered, through the respective major works of Patrice de La Tour du Pin and Christian Gabriel/le Guez-Ricord.

Neste trabalho foram estudadas as etapas de processo envolvidas na tecnologia Pin-in-Paste (PIP) de soldagem por refusão de componentes convencionais (THCs - Through Hole Components ou Componentes de Furo Passante) em placas de circuito impresso (PCIs), utilizando pasta de solda sem chumbo (lead-free) com liga SAC (Sn-Ag-Cu) de forma a atender as novas exigências ambientais para a montagem eletrônica. Inicialmente foi feito o projeto da PCI de teste com três diferentes componentes THCs e três componentes SMD com encapsulamentos distintos, com o objetivo de reproduzir uma PCI comercial. Foram gerados dois diâmetros de furos diferentes para inserir os THCs, possibilitando o estudo da variação de preenchimento com solda no PTH. Foi proposta uma equação para o cálculo do volume de pasta de solda a ser impresso sobre os furos no processo de montagem. A partir desta equação foram calculadas as dimensões dos furos do estêncil para a PCI de teste. Os parâmetros de impressão foram otimizados em função da variação de pressão e da velocidade do rodo. Duas curvas de refusão foram utilizadas, uma convencional e outra otimizada para verificar a variação na geração de defeitos. A impressão de pasta de solda ficou superior ao projetado, o que resultou em todas as amostras terem solda acima do parâmetro mínimo de aceitabilidade de volume de 75% de preenchimento do PTH. Esta sobre impressão ocasionou defeitos em boa parte dos componentes, excesso de solda nos filetes e resíduos de fluxo na solda nos PTHs. Tais defeitos foram expressivos para todos os THCs, mostrando que o excesso de pasta impressa foi decisivo na geração de defeitos para todas as combinações das variáveis estudadas. Os SMDs tiveram solda aceitável, apresentando apenas alguns casos de excesso de fluxo ou pouca solda em alguns QFPs devido ao uso de ilhas com dimensões maiores que o exigido em norma. O processo de Pin In Paste se mostra viável como substituto da solda onda em linhas de montagem para placas com SMDs e THCs, mas estudos posteriores deverão ser realizados para a geração de um modelo confiável de projeto de PCIs e estêncil com solda lead-free para que tal processo seja utilizado em grande escala na indústria. / This study describes the process steps involved in Pin-in-Paste (PIP) reflow soldering technology in printed circuit boards (PCBs) using lead-free solder paste with SAC alloy (Sn-Ag-Cu) in order to attend new environmental requirements for the electronics assembly. Initially it was designed a PCB test with three different THCs (Through Hole Component) and three different SMD (Surface Mount Device) packages in order to reproduce a commercial board. It was generated two different diameters of holes to insert the THCs, aiming to study the solder fill variation in PTH. An equation was proposed for calculating the volume of solder paste to be printed over the holes in the assembly process. From this equation it was calculated the dimensions of the holes of the stencil. The printing parameters were optimized according to the variation of pressure and speed of the squeegee. Two reflow curves were used in the process, a conventional one and an optimized one to determine the variations in the generation of soldering defects. The printed solder paste volume was higher than projected, which resulted in solder excess, causing defects in most of the components, such as excess solder in the fillet and solder flux residues in PTHs. Such defects were significant for all THCs, showing that the excess paste that was printed caused critical defects for all combinations of variables. Regarding that all samples were above the reflow minimum acceptable volume of 75% coverage of PTH. The SMDs solders were acceptable, with only few cases of solder flux excess. The Pin in Paste process was observed as a good option to replace the wave soldering thermal process for mixed PCBs. Further studies should be conducted to generate a reliable model of PCB and stencil design.

Setaria viridis tem sido utilizada como organismo modelo para gramíneas com metabolismo C4, buscando elucidar processos biológicos de plantas. A importância das monocotiledôneas com o metabolismo de C4 deve-se ao melhor balanço fotossintético quando comparado às plantas com metabolismo C3 em condições climáticas com altas temperaturas, como as que prevalecem no Brasil. Setaria viridis representa um sistema modelo de grande importância para a agricultura brasileira, uma vez que tanto a produção brasileira de biocombustíveis como de alimentos está fortemente relacionada aos organismos C4. Os hormônios vegetais são cruciais no estabelecimento de órgãos complexos desde o zigoto até o desenvolvimento da planta adulta. A auxina em particular, desempenha um papel fundamental na formação de um complexo sistema radicular nas plantas. Sabe-se que o transporte polar desse hormônio concentra a auxina em determinados tecidos, desempenhando um papel essencial na expressão diferencial de genes que modulam o desenvolvimento dos vários órgãos da planta. Monocotiledôneas e em particular Poaeceaes exibem um complexo sistema radicular que parece ser chave para o seu vasto potencial adaptativo, mas pouco se sabe sobre os fatores que envolvem as respostas sensoriais e de desenvolvimento que guiam a escolha de quais tipos de raiz as plantas elegem. O objetivo deste estudo foi explorar as vias hormonais e abióticas que influenciam a arquitetura das raízes / Setaria viridis has been used as a model organism for grasses with C4 metabolism, seeking to elucidate plant biological processes. The importance of monocotyledons with C4 metabolism is due to better photosynthetic balance when compared to plants with C3 metabolism in climatic conditions with high temperatures, such as those that prevail in Brazil. Setaria viridis represents a model system of great importance for Brazilian agriculture since both the Brazilian production of biofuels and food is strongly related to C4 organisms. Plant hormones are crucial in the establishment of complex organs from zygote to the adult plant development. Auxin in particular, plays a key role in the formation of a complex radicular system in plants. The polar transport of this hormone is known to concentrate auxin in particular tissues, playing an essential roll in the differential expression of genes that will modulate the development of the various plant organs. Monocots and in particular Poaeceae display a complex radicular system that seems to be key for it vast adaptive potential, but little is known about the factors involving the sensing and developmental responses that guide the choice of which root types to elect. The aim of this study was to explore the hormonal and abiotic cues that influence the root architecture