The need of using the underground space was limited in the human history, but in the last century and due to the increase of world population, the use of the underground space has become essential. Underground metro stations, deep garages, tunnels and basements, etc... are examples of using the underground space inside the cities. The use of underground space is conducted through deep excavation or tunneling. Several techniques are used to conduct the deep excavation and one of the most popular and well known techniques used for deep excavation is the diaphragm walling technique which is widely used specially inside the cities to safe space because it requires a very small space to conduct a deep reinforced concreted wall under the ground. However, the construction of such walls causes deformation of the surrounding ground and it could also affect the nearby existing structures. In some recorded cases the slurry trench failed and causes a great deformation which effect the nearby structures. However, Minor damages and cracks were observed in buildings near stable slurry trenches, because the soil deformation was high. The existing structures inside the cities have been constructed on shallow or deep foundations and this research was oriented to study the effect of diaphragm wall installation on the existing adjacent piled foundation. Very limited studies were made to investigate such an effect. At Cambridge university centrifuge model tests were conducted to investigate the effect of slurry reduction on single piles. Field observation was conducted in several projects and showed the settlement and deformation of buildings located on deep foundation during the diaphragm wall trenching. Numerical analysis was conducted using FLAC 3D to simulate the laboratory and the available field works. FLAC 3D is a commercial software and it depend in its analysis on finite difference method. The purpose of the simulation was to verify the used numerical analysis method. The results from the numerical analysis were in a good agreement with the available field data results, and they were also in good agreement with the laboratory test results regarding soil settlement but it was not in such good agreement when they were compared regarding the pile. Generally, from the verification the numerical analysis method is considered to be reliable. A parametric study was performed using the verified numerical analysis method. The flexible nature of the numerical analysis allows to simulate different cases and to study a variety of parameters. The output of the parametric study was the pile deflection, the bending moment and the shaft friction. The study was divided into three main parts while each part contains several parameter combinations. The first part studied the effect of the single and double panel(s) on the single pile group that has different piles numbers and formations. The second and third parts studied the effect of multiple panels on connected pile groups and piled raft foundation, respectively. Generally, the studied parameters can be divided into three main groups. The first is related to the trench which includes the panel dimension, the number of panels and the slurry level inside the panel. The effect of slurry pressure reduction at some levels inside the trench was also studied. The second group concerned the soil type and ground water level. The third group is related to the deep foundation which includes pile characteristics, location, and formation within the group. The results from the parametric study showed that the pile behavior was greatly affected by panel length, groundwater level, slurry level inside the trench and steadiness of the slurry pressure. The piles were also affected by the different stages of construction related to the pile location from the constructed panel. The piles within the group act together so they behave different from each other according to their position. The effect of the pile on the trench stability is presented through a simple analytical approach which is based on the wedge analysis. The analytical approach provided equations that calculate the factor of safety in two and three dimensions. The pile location was governing the equation that calculate the factor of safety because the pile could be fully inside the failure wedge or intersect with the failure surface. A comparative study was conducted to find out the effect of the different pile location and other parameters on the safety factor. Generally, this comparative study showed that the pile located within the failure wedge reduces the factor of safety, while the pile that intersects the failure surface could increase it. The pile row near a trench that contains piles inside the failure wedge and others intersects the failure surface act together to balance the failure wedge. The factor of safety results of some cases from the analytical approach were also compared with those calculated from the numerical analysis. In general, the factor of safety from the numerical analysis was higher than that calculated from the proposed analytical approach. This research helped to understand the trenching effect on the ground surface and on the nearby piled foundations. It provided charts that could help to predict the soil deformation and earth pressure coefficient which could be used in the design. It showed through the parametric study the precautions that should be taken into consideration during trenching process near piled foundation. This research provided a design method for the slurry trench panel near piled foundation.

Un nouveau matériau spintronique, Mn4N, a été étudié. Les couches minces ferrimagnétiques Mn4N possèdent une aimantation spontanée Ms relativement petite et une forte anisotropie magnétique perpendiculaire (PMA) et conviennent donc aux dispositifs à mémoire à couple de rotation. De plus, Mn4N est composé uniquement d’éléments bon marché, légers et abondants, sans terres rares ni métaux nobles, et donc exempt de criticité matérielle. Dans ce travail, les propriétés magnétiques et de magnéto-transport de Mn4N développé sur un substrat de SrTiO3 (STO) ont été évaluées.Tout d'abord, les propriétés magnétiques et magnéto-transport des films minces de Mn4N sont évaluées, ce qui permet de constater leur amélioration spectaculaire en remplaçant les substrats classiques en MgO par des substrats en STO. Ce système Mn4N / STO présente des propriétés étonnantes: une structure de domaine de taille millimétrique, une aimantation totalement rémanente à champ nul et une commutation d’aimantation nette provoquée par une faible nucléation de domaine inversé et une propagation en douceur de DW. Ces propriétés, associées à un très petit Ms et à un grand PMA, soulignent son potentiel pour les applications spintroniques.Deuxièmement, l’efficacité de génération du couple de transfert de spin (STT) dans le film mince Mn4N a été mesurée en mesurant la vitesse de la paroi de domaine (DW) entraînée par des impulsions de courant. La vitesse DW atteint des valeurs record de 900 m / s pour une densité de courant de 1,3 × 10 12 A / m2. Cette valeur est la plus élevée de tous les systèmes pilotés par le STT et est comparable à la vitesse la plus élevée obtenue avec les SOT. La mobilité DW η est également très grande, la plus élevée de tous les systèmes basés sur STT. L'ajustement de nos données à l'aide d'un modèle analytique 1D permet d'extraire une polarisation de spin des électrons de conduction de 0,81, ce qui suggère que Mn4N pourrait convenir à l'obtention de grandes magnétorésistances. De plus, ces propriétés étonnantes ont été obtenues sans aucun élément de terre rare, aucune structure d’empilement, ni assistance extérieure telle que des champs magnétiques / électriques ou des contraintes mécaniques.Enfin, les propriétés magnétiques ont été ajustées par une petite quantité d'introduction de Ni dans Mn4N. L'aimantation spontanée de Mn4N sur STO a été réduite par l'introduction de Ni avec maintien d'un PMA fort et rémanence totale. Ce résultat indique que le système ferrimagnétique Mn4N pourrait être compensé en substituant des atomes de Ni. Récemment, la compensation du ferrimagnet a été activement étudiée car le ferrimagnet compensé fournit une efficacité infinie en spin-couple. Les trois évidences de la compensation ont également été démontrées, l'inversion de l'angle de Hall anormal, la chiralité de rotation de Kerr et la dépendance de l'aimantation en fonction de la température. Le point de compensation de la composition a été estimé autour de Mn3.82Ni0.18N. Nous avons suggéré le modèle de compensation de Mn4N par l'introduction de Ni, qui est compatible avec la réduction par MS, l'inversion des courbes AHE, Kerr et M-T.En résumé, un potentiel de films Mn4N et Mn4-xNixN a été démontré comme un candidat prometteur pour les applications spintroniques telles que les dispositifs de mouvement DW induits par le courant avec de grandes propriétés: nucléation de domaine et propagation DW lisse, efficacité de génération de STT ultra-haute et accordabilité de la magnétisation par Ni-introduction. Ces propriétés étonnantes ont été réalisées sans terres rares ni métaux nobles, ce qui peut constituer une étape importante dans le remplacement des matériaux à base de terres rares par des éléments abondants. / A new spintronic material Mn4N has been investigated. Ferrimagnetic Mn4N thin films possess relatively small spontaneous magnetization Ms and strong perpendicular magnetic anisotropy (PMA) and thus are suitable for spin-torque based memory devises. In addition, Mn4N is composed of only cheap, light and abundant elements without any rare-earth nor noble metals., thus free from material criticality. In this work, magnetic and magneto-transport properties of Mn4N grown on SrTiO3 (STO) substrate have been evaluated.First, the magnetic and magneto-transport properties of Mn4N thin films are evaluated, resulting in finding out dramatically improvement of them by replacing conventional MgO substrates by STO substrates. This Mn4N/STO system exhibits astonishing properties: a millimeter-sized domain structure, fully remnant magnetization at zero field and a sharp magnetization switching caused by scarce nucleation of reversed domain and smooth DW propagation. These properties, associated to a very small Ms and a large PMA, underline its potential for spintronic applications.Second, the generation efficiency of spin-transfer torque (STT) in Mn4N thin film has been measured by measuring the speed of domain wall (DW) driven by current pulses. The DW velocity reaches record values of 900 m/s for a current density of 1.3×10^12 A/m2. This value is the highest in all STT-driven systems and is comparable to the highest speed obtained using SOTs. The DW mobility η is also very large, the highest in all STT-based systems too. Fit of our data using a 1D analytical model allows extracting a spin polarization of the conduction electrons of 0.81, suggesting that Mn4N could be suitable to obtain large magnetoresistances. In addition, these amazing properties have been achieved without any rare earth elements, stack structures, nor external assistance such as magnetic/electric field or mechanical stress.At last, the magnetic properties have been tuned by a small amount of Ni-introduction to Mn4N. The spontaneous magnetization of Mn4N on STO has been reduced by Ni-introduction with keeping strong PMA and full remanence. This result indicates the ferrimagnetic Mn4N system might be compensated by substituting Ni atoms. Recently compensation of ferrimagnet has been actively studied because the compensated ferrimagnet provides infinite spin-torque efficiency. The three evidences of the compensation have also been demonstrated, the reversal of anomalous Hall angle, Kerr rotation chirality, and the temperature dependence of magnetization. The compensation point of composition has been estimated around Mn3.82Ni0.18N. We suggested the compensation model of Mn4N by Ni introduction which is consistent with the MS reduction, the reversal of AHE, Kerr and M-T curves.In summary, a potential of Mn4N and Mn4-xNixN films has been demonstrated as a promising candidate for spintronic applications such as current induced DW motion devices with great properties: scares domain nucleation and smooth DW propagation, ultrahigh STT generation efficiency, and tunability of magnetization by Ni-introduction. These amazing properties have been achieved without rare-earth nor noble metal, which can be a milestone for replacement of rare-earth-based materials by abundant elements.

Thesis advisor: Robert Capalbo / The Presidential Scholars Program is a full tuition scholarship program offer to the 15 most outstanding applicants to Boston College each year. It involves three summer programs: a summer of service, an international summer experience, and a career development internship. The Program is funded by the Wall Street Council's Tribut Dinner to Boston College. During the first decade and a half of its existence, the Program has successfully fulfilled its mission to increase the intellectual standing of the University. / Thesis (BS) — Boston College, 2007. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: College Honors Program.

A 2014 study by the US Department of Energy conducted at Lawrence Berkeley National Laboratory estimated that U.S. data centers consumed 70 billion kWh of electricity[1]. This represents about 1.8% of the total U.S. electricity consumption. Putting this in perspective 70 billion kWh of electricity is the equivalent of roughly 8 big nuclear reactors, or around double the nation's solar panel output[2]. Developing new memory technologies capable of reducing this power consumption would be greatly beneficial as our demand for connectivity increases in the future. One newly emerging candidate for an information carrier in low power memory devices is the magnetic skyrmion. This magnetic texture is characterized by its specific non-trivial topology, giving it particle-like characteristics. Recent experimental work has shown that these skyrmions can be stabilized at room temperature and moved with extremely low electrical current densities. This rapidly developing field requires new measurement techniques capable of determining the topology of these textures at greater speed than previous approaches. In this dissertation, I give a brief introduction to the magnetic structures found in Fe/Gd multilayered systems. I then present newly developed techniques that streamline the analysis of Lorentz Transmission Electron Microscopy (LTEM) data. These techniques are then applied to further the understanding of the magnetic properties of these Fe/Gd based multilayered systems. This dissertation includes previously published and unpublished co-authored material.

La dynamique des paroi de domaine est utilisée dans de nombreux dispositifs de spintronique basés sur des micro et nanofils magnétiques pour la transmission et le stockage de l'information. La vitesse de la paroi de domaine est donc un des paramètres qui déterminent la vitesse de fonctionnement de ces dispositifs. Actuellement, un accent considérable est mis sur la compréhension de l'origine des grandes vitesses parois de domaines dans les microfils, qui peuvent atteindre 20 km/s. Dans ce travail, des fortes vitesses de parois ont été trouvées en présence de deux principaux facteurs: (i) une valeur relativement faible de l'anisotropie magnétique, et (ii) une distribution complexe de l'anisotropie magnétique due aux contraintes internes. En outre, la dynamique d'une paroi de domaine a été étudiée pour les échantillons à diamètre réduit, jusqu'à 1 μm. Il a été démontré que la dynamique d'une paroi de domaine est la même que dans les échantillons plus épais, ce qui confirme que les vitesses élevées ne sont pas seulement liées à la taille des microfils. L'observation directe de la structure de surface des parois de domaines par microscopie MOKE confirmé la forme de la paroi de domaine inclinée par rapport à l'axe du fil. Une nouvelle méthode a été proposée pour effectuer des observations sur des échantillons cylindriques. La structure inclinée de la paroi de domaine est jugée en partie responsable des valeurs élevées de vitesse apparente des parois de domaines mesurées par la méthode Sixte-Tonks dans ces microfils. / The domain wall dynamics is used in many spintronic devices based on the uniaxial ferromagnetic wires to transport and store information. Therefore, the domain wall velocity is one of the main parameters that determine the operation speed of these devices. Recently, a big attention is being paid to amorphous glass-coated microwires due to the very high domain wall velocities that reach up to 20 km/s. In this work, the fast domain wall propagation in amorphous glass-coated microwires was found in the presence of two main factors: (i) relatively low magnetic anisotropy, (ii) complex geometry of magnetic anisotropies given by internal distribution of mechanical stresses. The domain wall dynamics was examined in amorphous glass-coated microwires of reduced diameter down to 1 μm. It was shown, that the domain wall dynamics in these wires is the same as in wires of bigger diameter. It proves that the high domain wall velocities in microwires are not the effect of microwire diameter value. The direct observation of the surface domain wall structure by use of MOKE microscope confirmed that the domain wall is inclined relatively to the main axis. A new method for magneto-optical observation of the samples with cylindrical geometry was proposed. The inclined structure of the domain wall was found to be partially responsible for the high apparent domain wall velocity measured by the Sixtus-Tonks method in microwires. / Dynamika doménovej steny sa používa v mnohých spintronických zariadeniach na báze tenkých magnetických drôtoch na prenos a uchovávanie informácie. Rýchlosť doménovej steny je preto jedným z parametrov, ktoré určujú operačnú rýchlosť týchto zariadení. V súčasnosti je kladený značný dôraz na pochopenie pôvodu veľkých rýchlostí doménovej steny v mikrodrôtoch, kde rýchlosti dosahujú až 20 km/s. Veľké rýchlosti doménovej steny v mikrodrôtoch boli v tejto práci nájdené v prítomnosti dvoch faktorov: (i) relatívne nízka hodnota magnetickej anizotropie a (ii) zložitá distribúcia magnetických anizotropií daných vnútornými pnutiami. Navyše, dynamika doménovej steny bola študovaná aj na vzorkách s redukovaným priemerom až do 1 μm. Bolo ukázané, že dynamika doménovej steny je v týchto drôtoch rovnaká ako je tomu v hrubších vzorkách, čo potvrdzuje, že vysoké rýchlosti nie sú len efektom rozmeru amorfných, sklom potiahnutých mikrodrôtoch. Priame pozorovania povrchovej štruktúry doménovej steny pomocou MOKE mikroskopu potvrdili naklonený tvar doménovej steny vzhľadom na os drôtu. Bola navrhnutá nová metóda na vykonávanie magneto-optických pozorovaní valcových vzoriek. Naklonený tvar doménovej steny bol nájdený ako jeden z faktorov umožňujúcich zdanlivo veľké rýchlosti doménovej steny meraných Sixtusovou-Tonkosvou metódou na mikrodrôtoch.

Ce travail expérimental s’intéresse à l’écoulement en aval d’un swirler statique court. L’induction d’un mouvement de swirl est une solution connue pour augmenter le gradient pariétal de vitesse. L’augmentation du frottement pariétal présente un intérêt industriel dans les échangeurs de chaleur pour accroître leurs potentiels de transfert de chaleur et diminuer leurs vitesses d’encrassement. Nous proposons d’approfondir la connaissance des écoulements avec swirl décroissant à faibles nombres de Reynolds pour lesquels l’intérêt énergétique est a priori plus important. Dans un premier temps, le champ d’écoulement est caractérisé à l’aide de méthodes optiques, pour identifier le type de tourbillon caractérisant le swirl. Dans un second temps, la méthode électrochimique est utilisée pour mesurer le frottement pariétal instationnaire. Par analogie, ces mesures permettent d’obtenir une première estimation du transfert de chaleur en écoulement anisotherme. / This experimental work is interested in understanding the flow downstream a short static swirler. Inducing a swirl motion is a known solution to increase the wall velocity gradient. The increase in wall shear stress is useful in industrial heat exchangers in order to enhance their heat transfer capabilities and reduce their fouling rates. We try to go deeper into knowledge of decaying swirl flows, for low Reynolds number for which energy interest is greater a priori. First, we study the flow field with optical methods in order to identify type of vortex characteristics of the swirl. Second, electrochemical method is used to measure the unsteady wall shear stress. By analogy, these measurements give a first estimate of the heat transfer for the case of non-isothermal flows.

Lentilhas d´água são as menores angiospermas aquáticas monocotiledôneas, as quais são classificadas em duas subfamílias (Lemnoideae e Wolffioideae) que contemplam trinta e sete espécies representando cinco gêneros: Spirodela, Landoltia, Lemna, Wolffiella e Wolffia (APPENROTH; BORISJUK; LAM, 2013; BORISJUK et al ., 2015; FAO, 1999; LANDOLT, 1992, LES et al ., 2002). Essas plantas apresentam rápida reprodução vegetativa o que implica no acúmulo acelerado de carboidratos e proteínas, que por sua vez, confere uma enorme aplicação industrial e biotecnológica, especialmente na bioenergia (APPENROTH; BORISJUK; LAM, 2013; FAO, 1999). O balanço de carbono no crescimento relaciona-se com à assimilação fotossintética, armazenamento e consumo desses compostos, que são influenciados pela intensidade de luz (SMITH; STITT, 2007; STITT; ZEEMAN, 2012). O maior dreno de carbono assimilado é para a síntese de parede celular e sacarose, portanto, conhecendo a composição dos polissacarídeos e suas interações junto com o conteúdo de carboidratos não estruturais impacta a produção de combustíveis alternativos. O presente trabalho visou quantificar e analisar os carboidratos estruturais (açúcares de parede celular apiose, arabinose, fucose, ramnose, glicose, xilose, galactose e manose) e não estruturais (açúcares solúveis e de armazenamento sacarose, frutose, rafinose, glicose e amido) de três espécies de Lemnoideae e duas Wolffioideae comparando com as taxas de crescimento dessas plantas. / Duckweeds are the smallest aquatic monocots classified in two subfamilies (Lemnoideae and Wolffioideae) that contemplates thirty-seven species representing five genera: Spirodela, Lemna, Landoltia, Wolffia and Wolffiella . These plants display fast vegetative reproduction, which implies a rapid accumulation of carbohydrates and protein, conferring them biotechnological and industrial applications, especially in bioenergy. Carbon balance among growth is related to photosynthetic assimilation, storage, and consume of compounds which are influenced by light intensity. The major sink of the carbon assimilated is to cell wall and sucrose synthesis, thereby knowing the polysaccharides composition and their interactions together with the non-structural carbohydrates content may impact the alternative fuels production. The present work aimed to quantify and comparative analyze structural (cell wall sugars apiose, arabinose, fucose, rhamnose, glucose, xylose, galactose, and mannose) and nonstructural (storage and soluble sugars starch, sucrose, glucose, raffinose, and fructose) carbohydrates of three Lemnoideae and two Wolffioideae species correlating to its growth rates.

Att göra något som kallas för att “bryta den fjärde väggen” i spel, att adressera spelaren utöver spelmediets ramar, är något som har intresserat oss sedan länge. Att söka om den fjärde väggen och spel på internet har visat sig varit fruktlöst, tills vi upptäckte termen metalepsis. Metalepsis betyder bokstavligen “a jump across” och härstammar från berättarteori där det hanterar hur ett narrativs olika nivåer behandlas. I det här arbetet tar vi hjälp av Karin Kukkonens och Sonja Klimeks artiklar för att djupdyka i termen och dess användning i medier som litteratur, film och musik video samt spel. Vi tar hjälp av Astrid Ensslins och Huaxin Weis arbeten för att förstå varför metalepsis i spel är ett outforskat område och varför narrativen endast studeras på en ytlig nivå. Vi vill därför med frågeställningen “hur kan metalepsis användas i spel?” bidra med mer information om metalepsis i spel och undersöka en medveten användning i utvecklingen av ett spel. Genom att undersöka metalepsis i spel och andra medier, har vi skapat oss en uppfattning av hur det har använts upp till den här punkten för att sedan kunna applicera på vår gestaltning. Arbetet fokuserar på en metalepsis kallad Möbius Strip, som innebär ett narrativ som börjar om i sig självt. Utifrån Georg Kreislers bok Der Schattenspringer har vi tolkat hur en Möbius Strip kan se ut. Gestaltningen, i form av ett spel, har vi sedan byggt på den här tolkningen och jämfört resultatet med bokens version av metalepsen. Det vi har fått ut är fler konkreta exempel på hur metalepsis har och kan användas i spel. Vi har kunnat skapa diskussion om hur vår gestaltning förhåller sig till boken genom Sonja Klimeks beskrivning av Möbius Strip metalepsen. Vi har endast skrapat på ytan av det som kallas metalepsis i spel med det här arbetet, och anser att det finns fler vägar att undersöka. / The act of doing something that is called “breaking the fourth wall” in video games, to address the player across the games’ scope, is something that has been in our interest for a long time. To search about the fourth wall and video games on the internet have been futile, until we stumbled upon the term metalepsis. Metalepsis literally means “a jump across”, it originates from narratology and handles how the different levels in a narrative are managed. In this Bachelor Thesis we take a deep dive into the term, with the help of Karin Kukkonen’s and Sonja Klimek’s work, and how it’s used in different medias such as literature, film, music videos and video games. We discovered why metalepsis in video games is an uncharted area with the help of Astrid Ensslin’s and Huaxin Wei’s work, and why studies of narratives in video games are executed in a shallow grade. With our research question we want to contribute with more information about metalepsis in video games and to examine a conscious use of metalepsis in the development of a video game. By surveying metalepsis in video games and other media, we have created an estimate on how it has been used so far and then to applicate the observation to our video game. This thesis lay it’s focus on a metalepsis called Möbius Strip, that consists of a narrative that restarts within itself. Using Georg Kreisler’s book Der Schattenspringer, we have made an interpretation on how Möbius Strip could work out. We have then developed a video game based on this interpretation and compared the results to the books version of the metalepsis. What we have gathered with this thesis is more tangible examples of the use of metalepsis in video games so far. We have been able to create a discussion about how our interpretation of Möbius Strip relate to the book, with the help from Sonja Klimek’s description of the metalepsis. We have only managed to scrape the surface on the topic of metalepsis in video games and feel like there are multiple other roads to investigate.

Ces travaux ont pour contexte de participer à l’optimisation les cycles de décontamination des salles propres en utilisant un nouveau système de décontamination. Le principe de ce système est de décontaminer un volume par condensation de vapeur de peroxyde d’hydrogène sur toutes les parois intérieures du volume. Différents modèles de condensation et d’évaporation pariétaux ont été étudiés, développés et implémentés dans un code CFD, en incluant des modèles simples ainsi que des modèles plus complexes prenant en compte la forme de la phase liquide pariétale. En parallèle, afin de valider les modèles, un dispositif expérimental d’isolateur pour la décontamination a été utilisé afin de créer une base de données expérimentale de condensation de vapeur. Enfin, la validation de ce modèle numérique a été réalisée en comparant les résultats numériques fournis par le modèle développé dans une reproduction numérique de l’isolateur expérimental avec les résultats des expérimentations. / The context of this work is to contribute to the optimization of clean room decontamination cycles by using a new decontamination system. The concept of this system is to decontaminate a volume by condensing hydrogen peroxide vapour on all the inner walls of the volume. Different models of wall condensation and evaporation have been studied, developed and implemented in a CFD code, including simple models as well as more complex models taking into account the shape of the liquid phase at the wall. In parallel, in order to validate the models, an experimental isolator device for decontamination was used to create an experimental steam condensation database. Finally, the validation of this numerical model was carried out by comparing the numerical results provided by the model developed in a digital reproduction of the experimental isolator with the results of the experiments.

This study provides information to support the use of plant cell wall, from sugarcane bagasse, to produce cellulosic ethanol. Therewith, cell wall proteins from sugarcane cells cultures, leaves and culms were identified. To do so, different protocols were used. Using two-month-old leaves and culms, the extractions were performed using a destructive method, based on griding the tissues, submitting them to a growing gradient of succrose and centrifugation, being the cell wall extract later isolated by washing on a nylon net. After that, the cell wall proteins were extracted using two salts, 0,2 M CaCl2 and 2 M LiCl. Using cultured cells, a similar protocol was used, but it had a previous step of separation of the cell wall through grinding and precipitation in glycerol 15%. Using culms of the same age, a nondestructive protocol was tested based on vacuum infiltration of the tissues in the same salts already described, 0,2 M CaCl2 and 2 M LiCl, and posterior centrifugation. Two replicates were used from two-month-old plants and three in the case of suspension cells. The complex samples were digested, fractionated and sequenced through mass spectrometry, using SYNAPT G2HDMS coupled to nanoACQUITY, both from Waters. Peptides were processed using ProteinLynx 2.5 Global Server against sugarcane translated-EST database. Using bioinformatic programs, such as Blast2GO, it was possible to find the annotation and classification of similar proteins. Only proteins equally found in all repetitions were considered in the main analysis. SignalP, WolfPSORT, TargetP, TMHMM and Predotar were used to predict the subcellular location, both from ESTs and blasted proteins, and only the proteins predicted to be secreted in two or more programs were considered as cell wall proteins. Altogether, 157 different SAS related to sugarcane cell wall were found. Among these, 101 different cell wall proteins were characterized from eight functional classes. The method based on vacuum infiltration seems to be the most efficient one, since it had almost half, 48,84% of the proteins predicted to be secreted, which is a good percentage when comparing to other studies. From secreted proteins most of them were related to lipid metabolism, as lipid-transfer proteins, oxido-reductases, such as peroxidases, cell wall modifying enzymes, like glycoside-hydrolases, proteases, proteins with interacting domains, signaling proteins and several others. Results are in agreement with the expected role of the extracellular matrix in polysaccharide metabolism and signaling phenomena. Therefore, this work provided valuable information about sugarcane cell wall that can lead to future studies to enhance cellulosic ethanol production. / Este estudo fornece informação para auxiliar o uso da parede celular vegetal, a partir do bagaço de cana, para a produção de etanol celulósico. Com isso, as proteínas da parede celular de folhas, colmos e células em suspensão foram identificadas. Para isso, foram utilizados diferentes protocolos. Utilizando folhas e colmos de cana-de-açúcar de dois meses de idade, as extracções foram realizadas por meio de método destrutivo, com base na trituração dos tecidos, submetendo-os a gradiente crescente de sacarose e centrifugação, sendo a parede da célula extraída e depois isolada por lavagem sobre uma rede de nylon. Depois disso, as proteínas de parede celular foram extraídas utilizando dois sais, 0,2 M de CaCl2 e 2 M de LiCl. Para células em suspensão, um protocolo semelhante foi utilizado, contendo, no entanto, um passo anterior de separação da parede celular por meio de maceração e precipitação em glicerol 15%. Usando colmos da mesma idade, dois meses, um protocolo não destrutivo foi testado com base na infiltração a vácuo dos tecidos nos mesmos sais já descritos, 0,2 M de CaCl2 e 2 M de LiCl, e posterior centrifugação. Duas repetições foram usadas nos experimentos com plantas de dois meses de idade, e três, no caso de células em suspensão. As amostras complexas foram digeridas, fracionadas e seqüenciadas por espectrometria de massas, utilizando o equipamento SYNAPT G2HDMS acoplado ao cromatógrafo nanoACQUITY, ambos da Waters. Os peptídeos foram processadas utilizando ProteinLynx 2,5 comparando com a base de dados de ESTs traduzidos da cana. Utilizando programas de bioinformática, como Blast2GO, foi possível encontrar a anotação e classificação de proteínas semelhantes. Apenas proteínas igualmente encontradas em todas as repetições foram consideradas na análise principal. SignalP, WolfPSORT, TargetP, TMHMM e Predotar foram softwares utilizados para prever a localização subcelular, tanto para ESTs como proteínas, e apenas as proteínas preditas para serem secretadas por dois ou mais programas foram consideradas como proteínas de parede celular. Ao todo, 157 SAS diferentes relacionados à parede celular da cana foram encontrados. Dentre eles, 101 diferentes proteínas de parede foram caracterizadas em oito classes funcionais. O método baseado na infiltração a vácuo mostrou-se o mais eficiente, uma vez que apresentou quase metade, 48,84%, das proteínas preditas para serem secretadas, o que é um bom valor quando comparado com outros estudos. A maioria das proteínas secretadas estava relacionada com o metabolismo lipídico, como proteínas de transporte de lípidos, oxido-redutases, tais como peroxidases, enzimas modificadoras da parede, como as glicosil-hidrolases, proteases, proteínas com domínios de interação, proteínas sinalizadoras, entre outras. Os resultados estão de acordo com o papel que se espera da matriz extracelular no metabolismo de polissacarídeos e fenômenos de sinalização. Portanto, este trabalho forneceu informações valiosas sobre a parede celular da cana, tornando possível a utilização desses dados em futuros estudos para otimizar a produção de etanol celulósico.