Tesis sobre el tema "BCC"
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Liu, Xiaohua. "Spin Excitations in BCC, FCC, HCP Cobalt and BCC Fe1-xCox Alloys /". The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487932351057225.
Texto completoBabu, Bibin. "Connected Me : Hardware for high speed BCC". Thesis, Linköpings universitet, Institutionen för systemteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-79442.
Texto completoEllis, M. "The ductile to brittle transition in BCC metals". Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306220.
Texto completoValikova, Irina V. y Andrei V. Nazarov. "Simulation of diffusion under pressure in bcc metals". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-194630.
Texto completoValikova, Irina y Andrei Nazarov. "Simulation of diffusion under pressure in BCC metals". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-195673.
Texto completoSoin, Preetma Kaur. "First principles modelling of dislocations in BCC iron". Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/11752.
Texto completoValikova, Irina V. y Andrei V. Nazarov. "Simulation of diffusion under pressure in bcc metals". Diffusion fundamentals 3 (2005) 11, S. 1-15, 2005. https://ul.qucosa.de/id/qucosa%3A14298.
Texto completoValikova, Irina y Andrei Nazarov. "Simulation of diffusion under pressure in BCC metals". Diffusion fundamentals 2 (2005) 39, S. 1-2, 2005. https://ul.qucosa.de/id/qucosa%3A14369.
Texto completoTsai, Joshua Jr-Syan. "Micromechanisms of Near-Yield Deformation in BCC Tantalum". BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/8906.
Texto completoSinclair, Chad. "Co-deformation of a two-phase FCC/BCC material /". *McMaster only, 2001.
Buscar texto completoJennings, G. "Ultra-violet photoelectron spectroscopy of BCC- and FCC- iron". Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306636.
Texto completoSvenningsson, Leo. "Fourier transform of BCC andFCC lattices for MRI applications". Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-257148.
Texto completoNazarov, Andrei V., Alexander A. Mikheev, Irina V. Valikova, Aung Moe y Alexander G. Zaluzhnyi. "Kinetic of void growth in fcc and bcc metals". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-193483.
Texto completoNazarov, Andrei V., Alexander A. Mikheev, Irina V. Valikova, Aung Moe y Alexander G. Zaluzhnyi. "Kinetic of void growth in fcc and bcc metals". Diffusion fundamentals 6 (2007) 28, S. 1-2, 2007. https://ul.qucosa.de/id/qucosa%3A14203.
Texto completoKazim, Muhammad Irfan. "Variation-Aware System Design Simulation Methodology for Capacitive BCC Transceivers". Doctoral thesis, Linköpings universitet, Elektroniska Kretsar och System, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122840.
Texto completoThe series name Linköping Studies in Science and Technology. Thesis in the printed version is incorrect. The correct name is Linköping Studies in Science and Technology. Dissertations. This is corrected in the electronic version.
In the electronic published version minor errors in the acknowledgements and some typographical mistakes has been corrected.
Hayward, Erin G. "Atomistic studies of defects in bcc iron: dislocations and gas bubbles". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44761.
Texto completoLin, Peter Keng-Yu. "Evolution of grain boundary character distributions in FCC and BCC materials". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27994.pdf.
Texto completoWaterton, Michael. "Characterisation and evolution of the grain boundary network in BCC metals". Thesis, Swansea University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678443.
Texto completoLuciani, Giulia. "Strumento per la diagnosi di carcinoma bcc basato su spettroscopia di impedenza". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8586/.
Texto completoGilbert, Mark R. "BCC metals in extreme environments : modelling the structure and evolution of defects". Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:d972d28d-5d2d-4392-8cf5-fc5728dc74f6.
Texto completoValikova, Irina y Andrei Nazarov. "Simulation of pressure- and temperature dependence of impurity diffusion in BCC metals". Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-190167.
Texto completoRamos, Ricardo Jorge Barão. "Barragens em betão compactado com cilindros (BCC) - evolução e utilização em Portugal". Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/7628.
Texto completoA primeira e única barragem de betão compactado com cilindros (BCC) existente em Portugal foi construida em 2005 no Pedrógão. Actualmente encontra-se uma segunda barragem em construção e outras quatro em fase de projecto. Na presente dissertação descreve-se os diferentes tipos de construção de barragens, para além das de betão compactado com cilindros (barragens de aterro e de betão convencional). É também descrita a evolução da utilização do BCC aplicado a este tipo de obras, com especial relevo para a barragem de Pedrógão. São descritos também o método e os ensaios de granulometria, baridade e compactação para a realização de uma mistura de BCC aplicável em barragens, bem como os resultados obtidos. Esta dissertação tem como objectivo principal a realização de uma campanha de ensaios laboratoriais usando uma máquina de corte de diaclases (também conhecida por máquina de Hoek) que, por razões de logística, não foi possivel concretizar. Nos anexos sintetiza-se o trabalho experimental realizado tendo em vista a utilização da referida máquina para ensaios de corte em provetes fabricados com uma mistura de BCC, assim como uma descrição da máquina de Hoek.
Batista, Hugo Alexandre Antunes. "Análise térmica e estrutural de barragens de BCC - (betão compactado com cilindros)". Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/7836.
Texto completoO Betão compactado com cilindros (BCC) aplicado a barragens é uma técnica empregue inicialmente nos anos 70, mas bastante recente em Portugal. Este tipo de betão tal como o betão convencional sofre uma reacção exotérmica que se caracteriza pela libertação de calor, estando este fenómeno directamente relacionado com o calor de hidratação gerado, bem como da velocidade de colocação de cada camada e temperatura ambiente que se faça sentir no momento dessa colocação. Este fenómeno ocorre desde que é aplicado o betão e podendo perdurar muito após a completa construção da barragem. Neste seguimento são realizadas importantes tarefas em fase de projecto como a análise térmica e consequente análise estrutural para que por um lado se possa optimizar esta construção o máximo possível e por outro prever que a obra será terminada com todos os requisitos de desempenho, segurança e durabilidade. O presente trabalho foca-se na criação de um modelo em 2D utilizando um programa comercial de elementos finitos, o ANSYS, usando assim a sua funcionalidade Birth & Death para recriar a sequência de construção por camadas do betão compactado com cilindros (BCC). Este modelo foi aplicado à Barragem do Pedrogão, a primeira obra de BCC construída em Portugal e para isso foram usadas todas as propriedades do betão que foi empregue na mesma obra. Assim, é possível prever as variações de temperatura sentidas ao longo do tempo na barragem. Este modelo foi verificado quando os seus dados foram comparados às distribuições de temperatura registados na barragem do Pedrogão por meio de termómetros. Além disso é realizada uma análise de tensões podendo-se saber a probabilidade de ocorrência de tracções e compressões no corpo da mesma.
Valikova, Irina y Andrei Nazarov. "Simulation of pressure- and temperature dependence of impurity diffusion in BCC metals". Diffusion fundamentals 11 (2009) 53, 2009. https://ul.qucosa.de/id/qucosa%3A14015.
Texto completoHyde, Brian. "Effects of Carbon on Fracture Mechanisms in Nanocrystalline BCC Iron - Atomistic Simulations". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/27315.
Texto completoPh. D.
Yabuuchi, Kiyohiro. "Mn effect on irradiation hardening behavior and microstructural evolution in BCC Fe". Kyoto University, 2011. http://hdl.handle.net/2433/151904.
Texto completoBhattacharya, Arunodaya. "Ion irradiation effects on high purity bcc Fe and model FeCr alloys". Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112398/document.
Texto completoFeCr binary alloys are a simple representative of the reduced activation ferritic/martensitic (F-M) steels, which are currently the most promising candidates as structural materials for the sodium cooled fast reactors (SFR) and future fusion systems. However, the impact of Cr on the evolution of the irradiated microstructure in these materials is not well understood in these materials. Moreover, particularly for fusion applications, the radiation damage scenario is expected to be complicated further by the presence of large quantities of He produced by the nuclear transmutation (~ 10 appm He/dpa). Within this context, an elaborate ion irradiation study was performed at 500 °C on a wide variety of high purity FeCr alloys (with Cr content ranging from ~ 3 wt.% to 14 wt.%) and a bcc Fe, to probe in detail the influence of Cr and He on the evolution of microstructure. The irradiations were performed using Fe self-ions, in single beam mode and in dual beam mode (damage by Fe ions and co-implantation of He), to separate ballistic damage effect from the impact of simultaneous He injection. Three different dose ranges were studied: high dose (157 dpa, 17 appm He/dpa for the dual beam case), intermediate dose (45 dpa, 57 appm He/dpa for dual beam case) and in-situ low dose (0.33 dpa, 3030 appm He/dpa for the dual beam case). The experiments were performed at the JANNuS triple beam facility and dual beam in situ irradiation facility at CEA-Saclay and CSNSM, Orsay respectively. The microstructure was principally characterized by conventional TEM, APT and EDS in STEM mode. The main results are as follows: 1) A comparison of the cavity microstructure in high dose irradiated Fe revealed strong swelling reduction by the addition of He. It was achieved by a drastic reduction in cavity sizes and an increased number density. This behaviour was observed all along the damage depth, upto the damage peak. 2) Cavity microstrusture was also studied in the dual beam high dose irradiated FeCr alloys, and the results were compared to bcc Fe. The analysis was performed at an intermediate depth 300 – 400 nm below the surface (to avoid injected interstitial effect and surface effects), corresponding to 128 dpa, 13 appm He/dpa. TEM study revealed that the addition of small quantities of Cr, as low as 3wt.%, is highly efficient in strongly reducing void swelling. It was achieved by a drastic reduction of cavity sizes. For instance, average cavity size in Fe3%Cr was 0.9 nm as opposed to 6.8 nm in bcc Fe. Furthermore, the variation of void swelling as a function of Cr content is non-monotonic, with alocal maxima around 9 - 10wt.%Cr. 3) Coupling of conventional TEM, STEM/EDS and APT analysis on low and intermediate dose irradiated FeCr alloys revealed the presence of Cr enriched zones on the habit plane of the dislocation loops. This is expected to be due to radiation induced segregation (RIS) of Cr close to the core of the loops. As the loop grows under irradiation, the segregated areas are probably prevented from re-dissolution by impurity elements such as C. When imaged by TEM using classical diffraction contrast imaging techniques, these enriched zones produce displacement fringe contrast on the loop plane. A quantitative estimate of this enrichment was deduced by STEM/EDSand APT. The Cr content in these areas was between 23 - 35 at.% measured by EDS and 22 ± 2 at.% obtained by APT, whichis well below the Cr content of the Cr-rich α’ phase
Douat, Benjamin. "Étude de surfaces sous contrainte à l'échelle atomique : application au cas du niobium". Thesis, Poitiers, 2018. http://www.theses.fr/2018POIT2274/document.
Texto completoThe plastic deformation of body-centred cubic metals is the subject of extensive studies since more than half a century. It is now well established that the screw dislocations control the plasticity of these metallic metals. The reason for this is attributed to a non-planar configuration of the core of these dislocations, which induces a high friction force usually referred to as ‘pseudo-Peierls’. The underlying elementary mechanism is the thermally activated nucleation of kink pairs. While perfect screw dislocations do not have specific glide plane, the non-planar core configuration limits the number of possible slip planes. The slip traces observed at the meso and microscopic scales are wavy, which has leaded to the proposal of several possible slip planes.In this context, we propose an analysis at a finer scale, i.e. the atomic scale, of the slip traces produced by compressive stress on niobium single crystals at three temperatures in the thermally activated temperature regime, namely: 293 K, 200 K and 90 K. The analyses were carried out using a scanning tunnelling microscope under ultra-high vacuum environment. At this scale of observation, the slip traces are made up of crystallographic segments that can be associated with {011} and {112} planes. It is also noticeable that at 200 K and 293 K dislocation glide is observed in both the twinning and the anti-twinning directions. More importantly, all slip traces include segments that belong to {011} planes strongly supporting the latest ab initio atomistic simulations predicting a compact core configuration for screw dislocation.In this study, we also established that, at T = 293 K and 200 K, the sample surface may undergo drastic changes of its vicinal terraces, when they are close to emerging dislocations. The calculation of interaction forces, in the frame of isotropic linear elasticity, indicates that dislocations close to vicinal terraces do not play a major role regarding the stable positions of the vicinal terraces. However, they locally modify the chemical potential of the surface, thus enhancing atomic diffusion which is at the origin of the surface reorganisations experimentally observed
Schneider, Andreas Simon [Verfasser]. "Mechanical properties of small scale BCC metal structures / vorgelegt von Andreas Simon Schneider". Stuttgart : Max-Planck-Inst. für Metallforschung, 2010. http://d-nb.info/1004952171/34.
Texto completoMakarow, Irina. "Correlation of the elastic and plastic anisotropy of rolled FCC and BCC sheet". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66250.
Texto completoWang, Guofeng Goddard William A. Johnson W. L. "First principles based multiscale modeling of single crystal plasticity application to BCC tantalum /". Diss., Pasadena, Calif. : California Institute of Technology, 2002. http://resolver.caltech.edu/CaltechTHESIS:11132009-112545862.
Texto completoAdvisor names found in the Acknowledgements pages of the thesis. Title from home page. Viewed 01/13/2010. Includes bibliographical references.
Guo, Yaofeng. "Bêta-Bcc et alliages amorphes biocompatibles à base de titane pour les implants". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI017/document.
Texto completoThe Ti-based biocompatible human body implants of low Young's modulus and without toxic elements are developed in two regime of materials, crystalline Ti-Nb(-Sn) based alloys and amorphous Ti-Fe-Si based alloys. A series of Ti-Nb(-Sn) alloys were synthesized by copper mould suction casting and subjected to different heat treatments (furnace cooling or water quenching). The microstructure, thermal and mechanical properties of the as-cast and heat treated samples were investigated. It is shown that the addition of Sn increases the stability of the β phase. The Young's moduli of these alloys were also measured by ultrasonic measurements. Water-quenched Ti74Nb26 alloy was found to exhibits the lowest Young's modulus. Sn addition has little impact on the Young's moduli of the TiNb alloys. The Ti-Fe-Si based amorphous alloys were synthesized by melt spinning. The glass forming ability, thermal properties and corrosion properties of Ti-Fe-Si based alloys were investigated. The glassy compositions were designed according to the deep eutectic rule. It was found that the region near ternary eutectic point (Ti65Fe30Si5) is an icosahedral quasicrystal forming region, whereas the steeper side (Si rich side) of this ternary eutectic point is the glass forming region. Effect of minor elemental addition (Ge, Pd, Zr) on glass forming ability of the Ti-Fe-Si based alloys was also studied. The in situ observation of amorphization of Ti40Zr10Cu34Pd14Sn2 glassy alloy in synchrotron beam was conducted. The alloy was successfully vitrified in an aerodynamic levitation apparatus
Vasconcelos, Jean Rubens. "EstimaÃÃo da eficiÃncia tÃcnica dos Cursos de PÃs-GraduaÃÃo Stricto Sensu da Universidade Federal do CearÃ: triÃnio 2010 â 2012". Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11380.
Texto completoEste trabalho analisarà a eficiÃncia tÃcnica dos cursos de mestrado acadÃmico e de doutorado ofertados pela Universidade Federal do Cearà durante os anos de 2010, 2011 e 2012, tendo como base de dados os indicadores adotados pela CAPES para a consolidaÃÃo de sua avaliaÃÃo periÃdica dos cursos de pÃs-graduaÃÃo prescrita em lei. Como ferramenta de decisÃo, optou-se pelo uso da tÃcnica matemÃtica da AnÃlise EnvoltÃria de Dados â DEA, com orientaÃÃo ao produto e sob a perspectiva dos mÃtodos CCR e BCC, onde cada curso ou programa de pÃs-graduaÃÃo foi considerado uma DMU. No comparativo das inferÃncias apresentadas pelos dois modelos, pode-se observar uma tendÃncia de queda na eficiÃncia dos cursos ao longo do perÃodo investigado, apesar da alavancagem na quantidade de insumos durante esse mesmo tempo, evidenciando, pois, algumas desproporÃÃes entre as variÃveis, sobretudo no que concerne Ãs especificidades acadÃmicas inerentes a cada DMU, somadas ainda à ausÃncia de oferta para os cursos de doutorado em alguns programas.
This research will analyze the technical efficiency on academic master and doctorate courses offered by the Cearà Federal University in the years of 2010, 2011 and 2012, having as data base the indicators adopted by CAPES for the consolidation of its periodic evaluation prescribed by laws on post-graduate courses. As decision making tool, was chosen the mathematic technique of Data Envelopment Analysis â DEA, output oriented and under the perspectives of CCR and BBC models where every post-graduate program / course was considered a DMU. Comparing the inferences presented by both models, it could be observed a decreasing tendency of efficiency on courses throughout the investigation period, despite the input growth during this very same period, evidencing therefore, some discrepancies between the variants, mainly concerning academic specifications related to each DMU, also adding the lack of provision for doctoral courses in some study programs.
Escobedo, Juan Pablo. "Measurement of shear strength and texture evolution in BCC materials subjected to high pressures". Online access for everyone, 2007. http://www.dissertations.wsu.edu/Dissertations/Fall2007/j_escobedo_120507.pdf.
Texto completoGomes, De Aguiar Veiga Roberto. "Computational insights into the strain aging phenomenon in bcc iron at the atomic scale". Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00708423.
Texto completoKashinath, Abishek. "Helium behavior at fcc-bcc semicoherent interfaces: trapping, clustering, nucleation, and growth of cavities". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/88276.
Texto completoThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 153-171).
He implanted into metals precipitates into nanoscale bubbles that grow into voids, degrading the properties of engineering alloys in nuclear energy applications. In this thesis, multi-scale modeling techniques and neutron reflectometry measurements are used to study the He trapping, clustering and growth of clusters at fcc-bcc interfaces. Choosing Cu-Nb as a model fcc-bcc interface, a predictive Cu-Nb-He interatomic potential is constructed using density functional theory. These calculations show that two-body radial forces are sucient to describe interactions of He with fcc Cu and bcc Nb. Atomistic simulations reveal that He is initially trapped in the form of stable, sub-nanometer platelet-shaped clusters and not bubbles at the Cu-Nb interface. This behavior occurs due to the spatial heterogeneity of interface energy: He wets high energy, heliophilic regions while avoiding low energy, heliophobic ones. Using these insights, the maximum He concentration that can be stored without forming bubbles at any interface in terms of its location-dependent energy distribution may be predicted. The modeling predictions are validated by neutron reflectometry measurements, which show that interfacial He bubbles form only above a critical He concentration and provide evidence for the presence of stable He platelets below a critical He concentration. This work paves the way for the design of composite structural materials with increased resistance to He-induced degradation by tailoring the types of interfaces they contain.
by Abishek Kashinath.
Ph. D.
Srivastava, Ashish Kumar. "Orientation, Microstructure and Pile-Up Effects on Nanoindentation Measurements of FCC and BCC Metals". Thesis, University of North Texas, 2008. https://digital.library.unt.edu/ark:/67531/metadc6050/.
Texto completoSrivastava, Ashish Kumar Mirshams Reza. "Orientation, microstructure and pile-up effects on nanoindentation measurements of FCC and BCC metals". [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6050.
Texto completoAguiar, Veiga Roberto Gomes de. "Computational insights into the strain aging phenomenon in bcc iron at the atomic scale". Thesis, Lyon, INSA, 2011. http://www.theses.fr/2011ISAL0084/document.
Texto completoStatic strain aging is an important concept in metalurgy that refers to the hardening of a material that has undergone plastic deformation and then is aged for a certain period of time. A theory proposed in the late 1940s by Cottrell and Bilby explains this phenomenon as being caused by the pinning of dislocations by impurities (e.g., carbon atoms in solid solution) that migrate to the vicinity of the line defect. In the course of this PhD work, the atomistic mechanism behind the static strain aging phenomenon in bcc iron has been studied by means of computer simulations. Given the fact that diffusion in the solid state proceeds slowly, thus preventing the use of molecular dynamics at low temperatures (when the effect of the dislocation stress field on carbon diffusion is more pronounced), we have preferentially employed a method coupling molecular statics with atomistic kinetic Monte Carlo. Three major points have been addressed by this thesis: (i) the effect of the stress field of an edge or screw dislocation on a carbon atom diffusing nearby; (ii) the diffusion of a carbon atom in the tight channel found in the dislocation core (pipe diffusion); and (iii) the equilibrium carbon distribution in a Cottrell atmosphere. The main effect of the dislocation stress field outside the dislocation core consists of biasing carbon diffusion, such that some transitions become more likely than others. This effect is expected to drive the early stages of Cottrell atmosphere formation, when the mutual interaction between carbon atoms is negligible. Right in the dislocation core, as expected, carbon was seen to diffuse faster than in the bulk. Carbon concentration in the neighborhood of an edge or a screw dislocation was modeled by an approach based in statistical physics using the binding energies calculated by molecular statics, revealing a good agreement with experimental data obtained by atom probe techniques
Schold, Linnér Elisabeth. "Image processing on optimal volume sampling lattices : Thinking outside the box". Doctoral thesis, Uppsala universitet, Avdelningen för visuell information och interaktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-265340.
Texto completoVarillas, Javier. "A molecular dynamics study of nanocontact plasticity and dislocation avalanches in FCC and BCC crystals". Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667172.
Texto completoEn este estudio se investigan los mecanismos fundamentales para el desarrollo de las densas redes de defectos que se producen durante la deformación plástica de metales mediante ensayos uniaxiales y de indentación en escalas nanométricas. Estos procesos de deformación plástica se caracterizan por la producción de eventos intermitentes o avalanchas de dislocaciones. La investigación se basa en un extenso grupo de simulaciones de dinámica molecular en las que se emplean potenciales interatómicos del tipo embedded-atom method en cristales cúbicos centrados en las caras (CCC) y cúbicos centrados en el cuerpo (CC). La primera parte de esta tesis discute el papel combinado de la elasticidad y plasticidad en los nanocontactos. Se presta una especial atención a los mecanismos que llevan a la formación de nanohuellas plásticas así como al desarrollo de apilamiento de material alrededor del nanocontacto. Se encuentra que los arreglos topográficos de trazas de deslizamiento (emitidas a la superficie) muestran patrones específicos de deformación, los cuales son a su vez un rasgo distintivo de los mecanismos de deslizamiento de dislocaciones y procesos de nanomaclado que ocurren en los materiales CCC y CC en función de la temperatura y la orientación de la superficie. Se presenta un estudio mecanístico sobre la influencia de los eventos de nucleación de defectos, que llevan al desarrollo de una compleja red de defectos, sobre la nanodureza y su convergencia hacia un valor relativamente constante a medida que el indentador penetra en la superficie La modelización del comportamiento uniaxial de la zona deformada debajo de las nanoindentaciones permite la correlación entre ambos tipos de ensayos. Los resultados de esta comparación ilustran el importante papel que juegan los procesos de nucleación de dislocaciones sobre la formación de nanohuellas plásticas, lo que difiere (en términos mecanísticos) del comportamiento plástico convencional encontrado en escales micro y macroscópicas, donde el carácter evolutivo de una red de defectos preexistente gobierna la formación de huella, cumpliéndose así que cuanto mayor es la densidad de defectos, mayores son también las macro y microdurezas. En general, este trabajo aporta un trasfondo fundamental para comprender la razón por la que las superficies CC son más duras que las CCC en la nano escala. En la última parte de esta investigación se utilizan modelos de física estadística para investigar la influencia de los mecanismos de propagación de dislocaciones sobre la emisión de avalanchas plásticas. El análisis se basa en la noción de que la distribución del tamaño de las avalanchas sigue una ley potencial universal. Para investigar esta distribución en cristales cúbicos, se realizan un grupo de simulaciones novedosas donde las celdas computaciones, que contienen arreglos periódicos de las redes de dislocaciones, son sometidas a cargas uniaxiales a diferentes temperaturas y velocidades de deformación. A velocidades de deformación suficientemente lentas, las redes de dislocaciones evolucionan a través de la emisión de avalanchas que no se sobreponen en el tiempo, lo que ilustra que la movilización de las redes ocurre de tal manera que se garantiza una alternancia entre periodos de inactividad y cada evento plástico. La comparación entre resultados experimentales y computacionales lleva a encontrar la existencia de una magnitud de deslizamiento crítico que separa a dos regímenes de avalanchas cuya distribución de tamaños obedece leyes potenciales. Este resultado demuestra que los procesos de avalanchas son claramente dependientes de los mecanismos de deslizamiento e interacción de dislocaciones presentes en el material; aspecto que describe la transición entre el modelo de criticalidad gobernada por la tensión y el de criticalidad auto-organizada. Las simulaciones muestran los mecanismos específicos que caracterizan la emisión y propagación de avalanchas en metales CC y CCC en un amplio rango de temperatura, lo que es de gran importancia para justificar la utilización de estos modelos de criticalidad.
Kowalewski, Maciej Matthew Zbigniew. "Engineering and investigation of the interlayer exchange coupling in bcc Fe/Cu/Fe(001) structures". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0020/NQ37722.pdf.
Texto completoTarleton, Edmund. "Dislocation-dynamics modelling of crack-tip plastic zones and brittle-ductile transitions in BCC metals". Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526123.
Texto completoPatra, Anirban. "Modeling the mechanical behavior and deformed microstructure of irradiated BCC materials using continuum crystal plasticity". Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50366.
Texto completoGoel, Archak. "Design of Functionally Graded BCC Type Lattice Structures Using B-spline Surfaces for Additive Manufacturing". University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552398559313737.
Texto completoBodewits, Karin. "Biosynthesis pathway & transport of endotoxin : promising antibacterial drug targets in the Burkholderia cepacia complex (BCC)". Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5791.
Texto completoThompson, Gregory B. "Predicting Polymorphic Phase Stability in Multilayered Thin Films". The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1046469309.
Texto completoAndersson, Isak y Melki Karlsson. "Body Coupled Communication: Ändring av prototypkort". Thesis, Linköpings universitet, Elektroniksystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112864.
Texto completoCommunication using the human body as a transmission medium, the capacitive coupling between the skin and sensor, has been an active research area for PAN (Personal Area Network) since Thomas Guthrie Zimmerman introduced the technique in 1995. The reason for this is to examine the benefits and uses of a communication method that does not emit RF signals and thus reduce the risk of unauthorized interception. This report describes a thesis that examines the possibility of elimination of USB to UART converter on Microchip BodyCom through software USB-stack and combine this with Body Coupled Communication functionality in a single microcontroller. Furthermore, studies on if the application code in Body Coupled Communication transmitters can be modified to extend functionality. It was given in the conditions that microcontrollers from Microchip should be used, furthermore, low price and low power consumption were important, especially for the transmitter. The method for achieving this has been the use of Microchip BodyCom development kit with USB Microchip low pin count development kit and Microchip USB firmware framework. The result was that the USB- to UART-converter could be integrated with Microchip BodyCom, using software USB-stack and a modified program code for BodyCom in a single microcontroller. Only your imagination sets the limits for Body Coupled Communication can be used for. For example, it would be possible to exchange electronic business cards by a handshake or open a locked door only by using the handle.
Zermatten, Pierre-Jean. "Étude du transport tunnel dépendant du spin dans des jonctions tunnels magnétiques épitaxiées Fe/MgO/Fe bcc". Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00345079.
Texto completoUn dispositif original de mesures de transport sous champ magnétique d'objets de taille nanométrique a été développé au cours de cette thèse. Il associe une électronique d'acquisition rapide et un Microscope à Force Atomique (AFM) muni d'une pointe métallique. Ce dispositif très versatile permet de contacter électriquement et d'étudier de différents types de nano-objets sans étapes compliquées de nanofabrication.
Ce dispositif a été utilisé pour étudier l'influence des interfaces sur le transport dans des jonctions tunnel Fe/MgO/Fe (100) cristallines obtenues par épitaxie. Deux états résonants d'interface (IRS) ont été observés pour la première fois dans ce système à 0.2eV et 1.1eV au dessus du niveau de Fermi pour les électrons minoritaires. Ces IRS modifient fortement le transport tunnel et le dominent autour de 1V avec une inversion de la TMR dynamique. Une étude en fonction de l'épaisseur de MgO a permis de trouver la symétrie dominant le transport de ces IRS.
Rashetnikava, Alena, Alexander Germanov, Irina Valikova y Andrei Nazarov. "Molecular dynamics simulation of atomic structure in the vicinity of point defects in FCC and BCC metals". Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-190156.
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