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dc.contributor.advisorAcevedo-Rullán, Aldo
dc.contributor.authorParientes-Sánchez, Deyvi A.
dc.date.accessioned2019-05-06T17:40:37Z
dc.date.available2019-05-06T17:40:37Z
dc.date.issued2018-10-31en_US
dc.identifier.urihttps://hdl.handle.net/20.500.11801/2119
dc.description.abstractBrownian motion of a colloid suspended in a lyotropic chromonic liquid crystal (LCLC's) leads to the description of the transport properties of the medium through a unification of theories where the confinement effect is included. The understanding of the phenomenology of the system using a fluid considered a living liquid, with potential for multiple bioengineering applications, allows us to imitate natural systems, design new devices, and validate stochastic, empirical and virtual models. In this thesis the system is discretized by a mathematical conjecture which catalogs the information of the colloidal dynamics in relation to the stress by confinement of the colloidal system. Significant structural changes of the environment are described due to hydrodynamic disturbances caused by the presence of the colloid, which are in the order of the elastic forces and induce the fluid to behave in different ways. The bulk has similar properties as infinity, where there are no hydrodynamic disturbances caused by confinement and the isodesmic aggregation does not have a considerable impact on the colloidal dynamics. Outside the bulk where the colloid interacts with a surface, the structure of the medium reduces colloidal mobility as a function of the hydrodynamic distance, which is reflected in the increase in the size of the aggregates. Polymeric spherical colloids with radius (R) of 390 nm suspended in an LCLC's shows a similar behavior to gold colloids (R = 50 nm), relating these experiments to the confinement index, this being a third way outside the bulk: colloids between two plates. This discretization of the colloidal dynamics leads us to reveal the viscosity coefficients twist (ȠTwist) and splay (ȠSplay) for each mode, which can be obtained from the Leslie coefficients. However, the viscosity bend (ȠBend) is obtained with a mathematical model that depends on the aspect ratio of the aggregate. The values found for each of the coefficients ȠTwist, ȠSplay, and ȠBend from the colloidal dynamics in a nematic medium with the uniform director in confinement are in the same order as those found in literature.en_US
dc.description.abstractEl movimiento browniano de un coloide suspendido en un cristal líquido liotrópico cromónico (LCLC’s) conduce a la descripción de las propiedades de transporte del medio, mediante una unificación de teorías donde se incluye el efecto de confinamiento. El entender la fenomenología del sistema utilizando un fluido considerado un líquido viviente, con potencial para múltiples aplicaciones en bioingeniería, nos acerca a imitar sistemas naturales, diseñar nuevos dispositivos, validar modelos estocásticos, empíricos y digitales. En esta tesis se discretiza el sistema mediante una conjetura matemática que cataloga la información de la dinámica coloidal en relación con el estrés por confinamiento del sistema coloidal. Se distinguen cambios estructurales significativos del medio, debido a perturbaciones hidrodinámicas por la presencia del coloide, que son del orden de las fuerzas elásticas y que induce al fluido a comportarse en modos diferentes: Bulk, presenta propiedades semejantes en el infinito, no hay perturbaciones hidrodinámicas por confinamiento, donde la agregación isodésmica no tiene un impacto considerable en la dinámica coloidal. Fuera del bulk, coloide interactuando con una placa, la estructura del medio reduce la movilidad coloidal en función a la distancia hidrodinámica, que se refleja en el aumento del tamaño de los agregados. Por último, coloides esféricos poliméricos con radio (R) de 390 nm suspendidos en un LCLC’s, muestra comportamiento semejante a coloides de oro (R = 50 nm), relacionando estos experimentos con el índice de confinamiento, siendo esto un tercer modo fuera del bulk, coloides entre dos placas. Esta discretización de la dinámica coloidal nos lleva a revelar los coeficientes de viscosidad twist (ȠTwist) y splay (ȠSplay) para cada modo, que se pueden obtener a partir de los coeficientes de Leslie. Sin embargo, la viscosidad bend (ȠBend) se obtiene con un modelo matemático que depende de relación de aspecto del agregado. Los valores encontrados para cada uno de los coeficientes ȠTwist, ȠSplay y ȠBend a partir de la dinámica coloidal en un medio nemático con director uniforme en confinamiento están en el mismo orden a la encontrada en la literatura.en_US
dc.language.isoesen_US
dc.subjectLyotropic chromonic liquid crystalen_US
dc.subjectConfinement effecten_US
dc.subjectParticle dynamicsen_US
dc.subjectViscoelasticityen_US
dc.subject.lcshColloidsen_US
dc.subject.lcshParticle dynamics analysisen_US
dc.subject.lcshBrownian motion processesen_US
dc.subject.lcshLiquid crystalsen_US
dc.subject.lcshNematic liquid crystalsen_US
dc.subject.lcshViscoelasticityen_US
dc.titleSingle particle dynamics around the boundaries of nematic mediaen_US
dc.typeDissertationen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(c) 2018 Deyvi Alan Parientes Sánchezen_US
dc.contributor.committeeCórdova Figueroa, Ubaldo M.
dc.contributor.committeeSuleiman Rosado, David
dc.contributor.representativeZapata Medina, Rocío
thesis.degree.levelM.S.en_US
thesis.degree.disciplineChemical Engineeringen_US
dc.contributor.collegeCollege of Engineeringen_US
dc.contributor.departmentDepartment of Chemical Engineeringen_US
dc.description.graduationSemesterFallen_US
dc.description.graduationYear2018en_US


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