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Modelamiento hidrodinámico de flujo de transportadores en celdas fotovoltaicas basadas en semiconductores
(Universidad de Chile, 2014)
Hoy en día existe una necesidad creciente por mejorar las aplicaciones de la energía solar, en particular a través del uso de dispositivos a base de semiconductores. La base de la tecnología usada en las celdas fotovoltaicas es el dispositivo...
La Hermandad Cristiana de Puerto Octay: un testimonio de la religiosidad menonita en Chile
(Universidad de Chile, 2012)
Para Gabriel y Francisca,
que iluminan cada día con sus sonrisas.
iii
Agradecimientos
Para comenzar quisiera agradecer a las personas que hicieron posible la realización
de esta investigación y el presente trabajo, en primer lugar, al...
carácter de la vinculación de la comunidad con la sociedad chilena del siglo XXI en la que está inmersa. En función de lo anterior, es necesario, en primer lugar, hacer una breve revisión sobre la Reforma Protestante en Europa, aclarando que si bien el...
carácter de la vinculación de la comunidad con la sociedad chilena del siglo XXI en la que está inmersa. En función de lo anterior, es necesario, en primer lugar, hacer una breve revisión sobre la Reforma Protestante en Europa, aclarando que si bien el...
Expresión y modulación del canal de Ca2+ receptor de ryanodina tipo 2 (RyR2), un elemento clave para el aprendizaje y la memoria dependientes de hipocampo
(Universidad de Chile, 2019)
.................... 87
3.1. Participación de RyR2 durante el deterioro cognitivo en un modelo de EA .......... 87
3.2. El tratamiento con NAC previo al insulto con AβOs previene el deterioro cognitivo
y evita la alteración en los niveles de expresión de proteína RyR2...
los AβOs, previene el deterioro cognitivo, regula los niveles de RyR2, Arc y p-ERK1/2 y previene el aumento de canales RyR en estado de alta actividad (más oxidados), manteniendo un perfil similar al de los individuos control. Considerando los...
los AβOs, previene el deterioro cognitivo, regula los niveles de RyR2, Arc y p-ERK1/2 y previene el aumento de canales RyR en estado de alta actividad (más oxidados), manteniendo un perfil similar al de los individuos control. Considerando los...
Estudio termodinámico de la formación de complejos de inclusión de ariloxazinonas y ariloxazoles con ciclodextrinas y evaluación de aplicaciones fotofísicas
(Universidad de Chile, 2016)
En esta tesis se estudiaron tanto las características fisicoquímicas de los complejos de inclusión de derivados de ariloxazinonas y arilnaftoxazoles en ciclodextrinas y se determinaron los parámetros termodinámicos que controlan el proceso de...
In this thesis, the physicochemical characteristics of the inclusion complexes of aryloxazinones and arylnaphthoxazoles derivatives in cyclodextrins were studied. In addition, the thermodynamic parameters that control the inclusion process were determined. To accomplish these purposes, techniques and methodologies that involve measurement of steady-state and time resolved fluorescence were used. The inclusion constants (K) were obtained using both, the Benesi-Hildebrand and the phase solubility methodologies. The experiments showed that both families of molecules form inclusion complexes with cyclodextrins with a 1:1 stoichiometry, and they present a great affinity for the β-cyclodextrin cavity (K>100 M-1). The oxazinones who have electrodonating substituents, like amine or N,N-dimethylamine, have the largest inclusion constants (K= 486 ± 0,5 M-1 (6-amino-2-phenyl-3H-naphtho[2,1-b][1,4]oxazin-3-one) and K= 604 ± 0,4 M-1 (6-(dimethylamino)-2-phenyl-3H-naphtho[2,1-b][1,4]oxazin-3-one)). Also, the arylnaphthoxazoles who have a vynilic bridge have higher inclusion constants than those which are directly linked to the oxazole ring, for example 2-(quinolin-2-yl)naphtho[2,1-d]oxazole, K = 326 ± 6 M-1 and 2-(2-(quinolin-2-yl)vynil)naphtho[2,1-d]oxazole, K = 515 ± 6 M-1. Thermodynamic parameters that control the inclusion process were determined using classic thermodynamic equations such as the van't Hoff equation. Furthermore, the ΔG° are negative and they are in the range of -1 to -5 kcal/mol, indicating that the inclusion process is thermodynamically favored. Values of ΔG° shows that arylnaphthoxazoles are more compatible with the β-cyclodextrin cavity than the aryloxazinones. Using the analysis of the dependence of the free energy, enthalpy and entropy of inclusion process with the guest structure, it was possible to determinate if the cyclodextrin/guest interactions are the ones that control the inclusion or if the predominant driven force is the hydrophobic effect. It was found that for aryloxazinones the thermodynamic control is primarily enthalpic, whereas for aryloxazoles the entropy controls the inclusion process. In addition, studies of molecular modeling were performed using both, docking and molecular dynamics methodologies, in addition to analysis of natural bond orbitals (NBO) in order to optimize the geometry of the guest-cyclodextrin complex and estimate the more important interactions contributing to the formation of the association complex. The results obtained were compared with the experimental data, finding a good fit between them. Furthermore, a system to produce white light in solid phase using a β-cyclodextrin modified with a sulfonic acid group was developed. The compound (E)-2-(2-(quinolin-2-yl)vinyl)naphtho[1,2-d]oxazole, included in the modified cyclodextrin cavity, shows an emission spectra comprising with the visible range with characteristic similar to white light. Additionally, the (E)-2-(2-(furan-2-yl)vinyl)naphtho[1,2-d]oxazole included in the β-cyclodextrin cavity, change its photophysical/phochemical behavior relative to that the observed for the uncomplexed molecule. This behavior allows to propose this system as a new fluorescent probe capable to detect excited singlet oxygen in aqueous media operating as an "switch" on-off...
In this thesis, the physicochemical characteristics of the inclusion complexes of aryloxazinones and arylnaphthoxazoles derivatives in cyclodextrins were studied. In addition, the thermodynamic parameters that control the inclusion process were determined. To accomplish these purposes, techniques and methodologies that involve measurement of steady-state and time resolved fluorescence were used. The inclusion constants (K) were obtained using both, the Benesi-Hildebrand and the phase solubility methodologies. The experiments showed that both families of molecules form inclusion complexes with cyclodextrins with a 1:1 stoichiometry, and they present a great affinity for the β-cyclodextrin cavity (K>100 M-1). The oxazinones who have electrodonating substituents, like amine or N,N-dimethylamine, have the largest inclusion constants (K= 486 ± 0,5 M-1 (6-amino-2-phenyl-3H-naphtho[2,1-b][1,4]oxazin-3-one) and K= 604 ± 0,4 M-1 (6-(dimethylamino)-2-phenyl-3H-naphtho[2,1-b][1,4]oxazin-3-one)). Also, the arylnaphthoxazoles who have a vynilic bridge have higher inclusion constants than those which are directly linked to the oxazole ring, for example 2-(quinolin-2-yl)naphtho[2,1-d]oxazole, K = 326 ± 6 M-1 and 2-(2-(quinolin-2-yl)vynil)naphtho[2,1-d]oxazole, K = 515 ± 6 M-1. Thermodynamic parameters that control the inclusion process were determined using classic thermodynamic equations such as the van't Hoff equation. Furthermore, the ΔG° are negative and they are in the range of -1 to -5 kcal/mol, indicating that the inclusion process is thermodynamically favored. Values of ΔG° shows that arylnaphthoxazoles are more compatible with the β-cyclodextrin cavity than the aryloxazinones. Using the analysis of the dependence of the free energy, enthalpy and entropy of inclusion process with the guest structure, it was possible to determinate if the cyclodextrin/guest interactions are the ones that control the inclusion or if the predominant driven force is the hydrophobic effect. It was found that for aryloxazinones the thermodynamic control is primarily enthalpic, whereas for aryloxazoles the entropy controls the inclusion process. In addition, studies of molecular modeling were performed using both, docking and molecular dynamics methodologies, in addition to analysis of natural bond orbitals (NBO) in order to optimize the geometry of the guest-cyclodextrin complex and estimate the more important interactions contributing to the formation of the association complex. The results obtained were compared with the experimental data, finding a good fit between them. Furthermore, a system to produce white light in solid phase using a β-cyclodextrin modified with a sulfonic acid group was developed. The compound (E)-2-(2-(quinolin-2-yl)vinyl)naphtho[1,2-d]oxazole, included in the modified cyclodextrin cavity, shows an emission spectra comprising with the visible range with characteristic similar to white light. Additionally, the (E)-2-(2-(furan-2-yl)vinyl)naphtho[1,2-d]oxazole included in the β-cyclodextrin cavity, change its photophysical/phochemical behavior relative to that the observed for the uncomplexed molecule. This behavior allows to propose this system as a new fluorescent probe capable to detect excited singlet oxygen in aqueous media operating as an "switch" on-off...
Análisis estocástico de estabilidad de pequeña señal en sistemas eléctricos de potencia
(Universidad de Chile, 2012)
El estudio de estabilidad en Sistemas Eléctricos de Potencia consiste en determinar la condición de operación del sistema luego de ocurrida una perturbación. El enfoque clásico considera tres tipos de análisis: Angular, Frecuencia y Voltaje. Los...
Los mapuchismos en el DRAE
(Universidad de Chile, Facultad de Filosofía y Humanidades, 2010)
Este artículo trata del léxico proveniente del idioma mapuche (mapudungun(n) contenido en la última edición (vigésimo segunda) del Diccionario de la Real Academia Española (DRAE). Se propone la voz mapuchismo(s) para dicho léxico, así como ya existe...
Análisis del grado y patrón de fracturamiento de macizos rocosos. Caso de estudio :|bPared sureste del yacimiento tipo pórfido cuprífero Cuajone, Departamento de Moquegua, Perú
(Universidad de Chile, 2014)
fracturamiento del macizo rocoso es de indudable importancia y una necesidad de
primer orden en la minería. Particularmente en la de superficie, donde es de utilidad en
la evaluación de la calidad geotécnica del macizo, los parámetros de diseño, los índices
de...
UNIVERSIDAD DE CHILE FACULTAD DE CIENCIAS FÍSICAS Y MATEMÁTICAS DEPARTAMENTO DE GEOLOGÍA ANÁLISIS DEL GRADO Y PATRÓN DE FRACTURAMIENTO DE MACIZOS ROCOSOS. CASO DE ESTUDIO: PARED...
UNIVERSIDAD DE CHILE FACULTAD DE CIENCIAS FÍSICAS Y MATEMÁTICAS DEPARTAMENTO DE GEOLOGÍA ANÁLISIS DEL GRADO Y PATRÓN DE FRACTURAMIENTO DE MACIZOS ROCOSOS. CASO DE ESTUDIO: PARED...
Is your English good or bad? : Social representations towards Alexis Sánchez's use of English in his first interview in that language: theoretical and methodological implications on teaching English as a foreign language
(Universidad de Chile, 2016)
Universidad de Chile
Facultad de Filosofía y Humanidades
Departamento de Lingüística
Is your English good or bad?: Social representations towards Alexis Sanchez´s use of
English in his first interview...
in that language. Theoretical and methodological implications on teaching English as a foreign language Informe final de Seminario para optar al grado de Licenciado en Lengua y Literatura Inglesas Walesca Contreras Labra – Fabián Grez Peñaloza...
in that language. Theoretical and methodological implications on teaching English as a foreign language Informe final de Seminario para optar al grado de Licenciado en Lengua y Literatura Inglesas Walesca Contreras Labra – Fabián Grez Peñaloza...
Study on the limiting factors of a coherent optical fiber link, applied to phase transfer for femtosecond synchronization
(Universidad de Chile, 2013)
El Gran Conjunto Milimétrico / submilimétrico de Atacama (ALMA) es el observatorio astronómico más grande jamás construido. Se encuentra ubicado en el Llano de Chajnantor, a una altitud de 5.000 metros sobre el nivel del mar en el norte de Chile. Se...
Un estudio comparativo de la frecuencia de ocurrencia de las expresiones evaluativas en textos expositivos científicos en inglés
(Universidad de Chile, 2012)
Nuestra investigación ha consistido en un estudio comparativo de la frecuencia de ocurrencia de tanto los „patrones sintácticos evaluativos‟ (Hunston y Sinclair 2001) como de los „significados valorativos‟ (Martin y White 2005) i.e., significados...