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

Aproximación epistemológica aplicada a conceptos relacionados con la condición y habilidades físicas

El presente trabajo analiza el significado y utilización de diferentes conceptos relacionados con la actividad física, el estado de forma del individuo y su valoración o evaluación. Asimismo, se compara las aportaciones de diversos autores especializados, quedando de manifiesto cómo determinados términos puedan ser utilizados con significados diferentes por varios interlocutores, e incluso empleados en contextos asociados a ideas y objetivos de distinta consideración. Entre los términos más utilizados en la bibliografía especializada relacionados con el tema que aquí cometemos podemos encontrar: Prueba de condición, condición física, physical fitness, condición motriz, aptitud, aptitud física, actividad física, capacidad, cualidad, habilidad, test, condición biológica, condición motora, condición psíquico-sensorial, fitness, etc

Aplicación de la prueba de lanzamiento de balón medicinal, abdominales superiores y salto horizontal a pies juntos: resultados y análisis estadístico en educación secundaria

Se propone en este artículo un estudio sobre tres pruebas muy utilizadas en el ámbito educativo para valorar la fuerza del individuo. Estos tests (lanzamiento de balón medicinal, prueba de abdominales superiores en 30 seg. y salto horizontal a pies juntos) destacan entre los más utilizados por el profesorado de educación física. Se ha realizado un estudio sobre los criterios de calidad de los mismos, así como una aplicación a 505 alumnos de educación secundaria. El análisis de los resultados permite obtener amplios valores estadísticos y ha facilitado la elaboración de baremos de calificación clasificados por sexo en cada uno de los diferentes niveles educativos de la educación secundaria

Reflexiones sobre las prioridades actuales de la Educación Física

Aunque la Educación Física se ha consolidado como área dentro del sistema educativo, socialmente no ha variado mucho y aún está por llegar el momento en que se reconozca la verdadera importancia de la misma. Paradójicamente, aunque la relación actividad física-salud está científicamente demostrada, y se ofrece muy frecuentemente resultados estadísticos sobre su incidencia en la calidad de vida, tanto en la adolescencia como en las etapas de madurez y vejez, y aunque en los espacios mediáticos se revela la necesidad de su práctica constante en cualquiera de sus formas (deporte, actividades en la naturaleza, gimnasia, aeróbic, etc.) sólo un pequeño porcentaje de la población lo ha adquirido como hábito propio