Diffusion-reaction modelling of the degradation of oil-well cement exposed to carbonated brine

The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process.The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process

Diffusion-reaction modelling of the degradation of oil-well cement exposed to carbonated brine

The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process.The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process

Diffusion-reaction modelling of the degradation of oil-well cement exposed to carbonated brine

The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process.The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process

Zero-thickness interface model with chemical degradation by acid attack

Carbon dioxide (CO2) storage in abandoned oil/gas reservoirs is considered a viable alternative to reduce greenhouse gas emissions to the atmosphere. An important element of the risk associated with long-term CO2 storage is the loss of integrity of the cement seals of the abandoned wells in the reservoir. Among others, one possible cause of loss of integrity is the degradation of the oil-well cement due to the acid attack of the carbonated brine in the reservoir. In previous studies, the authors have developed a diffusion-reaction model for simulating this degradation process. In order to study possible coupled Chemo-Mechanical (CM) mechanisms, this model will be coupled with an existing mechanical model. For this purpose, in this paper, an existing constitutive law for zero-thickness interface, based on the theory of elasto-plasticity with concepts of fracture mechanics, is modified to incorporate the effect of chemical degradation on the mechanical strength parameters. Preliminary results obtained with this new constitutive law are presented, in order to illustrate the main aspects of the proposed constitutive law, as well as a possible C-M degradation mechanism that should be considered in the long-term safety assessment of CO2 geological storage projects

Silencio, el aliento es un don del cielo

Abstract not availabl

A pan-tilt camera Fuzzy vision controller on an unmanned aerial vehicle

is paper presents an implementation of two Fuzzy Logic controllers working in parallel for a pan-tilt camera platform on an UAV. This implementation uses a basic Lucas-Kanade tracker algorithm, which sends information about the error between the center of the object to track and the center of the image, to the Fuzzy controller. This information is enough for the controller, to follow the object moving a two axis servo-platform, besides the UAV vibrations and movements. The two Fuzzy controllers of each axis, work with a rules-base of 49 rules, two inputs and one output with a more significant sector defined to improve the behavior of those

Efecto del uso de claves en la recuperacion de la informacion desde la memoria episodica en ninos con trastorno especifico del lenguaje y ninos control pareados por nivel de desarrollo lingüistico

99 p.Recientes estudios señalan que los niños con Trastorno específico del Lenguaje, además de presentar dificultades en la memoria de trabajo, presentan dificultades para procesar información contextual. De la misma manera, se ha estudiado que la presencia de claves de codificación o recuperación juega un rol poco significativo en el recuerdo de información desde la memoria episódica, contrario a lo que sucede en niños de igual edad cronológica en donde la presencia de claves, mejora el recuerdo. El presente estudio está dirigido a estudiar el efecto del uso de claves en el recuerdo de información episódica en niños con TEL y niños control pareados por nivel de desarrollo lingüístico, a fin de determinar cuan específico es éste trastorno, el papel que juega el lenguaje expresivo y comprensivo, la presencia de claves de codificación y recuperación y el grado de relación semántica entre los estímulos en el recuerdo de la información episódica en niños con TEL. Se trabajó con 24 sujetos, 12 de los cuales presentaban TEL expresivo y 12 controles de la misma edad lingüística. Los datos de los niños con TEL, fueron extraídos de los estudios realizados por González, (2007) y Guerra (2007) y los niños control provenían de centros de educación preescolar de la ciudad de Talca

Diffusion-reaction modelling of the degradation of oil-well cement exposed to carbonated brine

The essential aspects of a diffusion-reaction model in development for the degradation process of oil-well cement exposed to carbonated brine are presented in this paper. The formulation consists of two main diffusion/reaction field equations for the concentrations of aqueous calcium and carbon species in the hardened cement paste pore solution, complemented by a number of chemical kinetics and chemical equilibrium equations. The volume fraction distribution of the solid constituents of the hardened cement paste and the reaction products evolve with the progress of the reaction, determining the diffusivity properties of the material. A sensitivity analysis of some parameters of the model is presented to illustrate the capabilities to reproduce realistically some aspects of the degradation process.Postprint (published version

La gestión de prensa en el Congreso de la República. Difusión de la labor parlamentaria (2008 -2009)

Muestra el trabajo de los comunicadores en la gestión de prensa y el papel de los medios de comunicación en la labor parlamentaria, mediante la sistematización de un caso: la experiencia desarrollada en la coordinación de prensa en la Comisión de Descentralización, Regionalización, Gobiernos Locales y Modernización del Estado del Congreso de la República y el despacho de la congresista Rosa Florián Cedrón, en el periodo 2008 – 2009.Trabajo de suficiencia profesiona

Presencia de la viralización en el video BTS IDOL Official MV en el canal de Youtube de Big Hit Entertainment en jóvenes de 15 a 23 años en el CC Arenales, Lince 2019

El siguiente trabajo tuvo como propuesta principal el determinar la presencia de la viralización en el video del grupo coreano BTS (Beyond The Scene), que tiene por nombre “Idol”, material audiovisual que fue lanzado el 24 de agosto del 2018 a través de su canal en Youtube llamado “Big Hit Entertainment”, siendo esta la empresa dueña del grupo, entre los jóvenes de 15 a 23 años, quienes son el público asiduo al Centro Comercial Arenales ubicado en el distrito de Lince, en el presente año 2019. El enfoque utilizado fue el cuantitativo aplicado, el nivel fue descriptivo simple con un diseño no experimental de tipo corte transversal. La técnica para la recolección de datos fue el cuestionario y como instrumento se utilizó la encuesta de 20 preguntas, en base a la escala de Likert. La herramienta de recolección de datos alcanzó un 91% de validez a través del coeficiente V de Aiken, luego de revisado y firmado por expertos en la materia y con un 0.97 de Alfa de Cronbach, cumpliendo de esta forma, el criterio de validez y confiabilidad. Los datos recolectados fueron procesados y analizados en el programa SPSS con el método de frecuencia, teniendo también el resultado de la media aritmética en los ítems generales que permitió corroborar y asegurar resultados precisos determinando que en el videoclip existe la presencia de la viralización expuesta por Peschiera en donde se caracteriza por el número de vistas, likes y el poder identificarse y compartir un contenido a un gran nivel sin importar límites geográficos, teniendo un nivel muy alto de 79% entre los ítems “totalmente de acuerdo” y “de acuerdo”, mientras que la dimensión de difusión fue la que más destacó al tener un nivel muy alto de 83% entre las opciones de “totalmente de acuerdo” y “de acuerdo”