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Uno de los problemas más graves que encuentran los alumnos de los primeros cursos de las licenciaturas de Economía y Administración y Dirección de Empresas consiste en que no logran enfrentarse con confianza a las asignaturas cuantitativas, especialmente las Matemáticas y la Estadística. En esta comunicación nos centramos, especialmente, en el proceso de enseñanza-aprendizaje de la última materia y pretendemos presentar las líneas propuestas en nuestro Departamento para hacer la Estadística una materia más comprensible, atractiva y cercana a los alumnos y para que éstos estén más motivados en su estudio, ayudados por una herramienta interactiva de trabajo, diseñada por los autores, que también se describe en este artículo. Como las nuevas tecnologías se introducen cada vez más en el ámbito educativo, en este trabajo se presenta un programa de software que permite a los alumnos aprender Estadística de una manera más divertida y didáctica, pues el programa consiste en un juego de ordenador, de interfaz muy fácil y muy atractivo en su presentación.

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Simulation of gas adsorption in flexible porous materials is still limited by the slow progress in the development of flexible force fields. Moreover, the high computational cost of such flexible force fields may be a drawback even when they are fully developed. In this work, molecular simulations of gas adsorption and diffusion of carbon dioxide and methane in NH2-MIL-53(Al) are carried out using a linear combination of two crystallographic structures with rigid force fields. Once the interactions of carbon dioxide molecules and the bridging hydroxyls groups of the framework are optimized, an excellent match is found for simulations and experimental data for the adsorption of methane and carbon dioxide, including the stepwise uptake due to the breathing effect. In addition, diffusivities of pure components are calculated. The pore expansion by the breathing effect influences the self-diffusion mechanism and much higher diffusivities are observed at relatively high adsorbate loadings. This work demonstrates that using a rigid force field combined with a minimum number of experiments, reproduces adsorption and simulates diffusion of carbon dioxide and methane in the flexible metal–organic framework NH2-MIL-53(Al). [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate growth, chlorophyll content, and photosynthesis in Jatropha at different levels of soil moisture. Plants were cultivated in containers and the treatments of the soil water content evaluated were: 0% (without watering), 20, 40, 60, and 80% soil water content. Plant height was statistically similar for all treatments, but the number of leaves differed significantly. Total dry matter and chlorophyll at 40, 60, and 80% soil water content were statistically similar, but different from 0 and 20% soil water content. Leaf area at 40, 60, and 80% soil water content was statistically different from 0 and 20% soil water content. The photosynthetic rate, transpiration and stomatal conductance at 60 and 80% soil water content were statistically similar but different from 0 and 20% soil water content. Water stress affected growth, chlorophyll content, photosynthetic rate, transpiration, and stomatal conductance. [ABSTRACT FROM AUTHOR]

Abstract: Molecular dynamics simulations were carried out to determine the self-diffusivities of CH4 and CO2 both for pure components and in 50–50 mixtures for a range of molar loadings in MFI, CHA and DDR zeolites. In CHA and DDR zeolites, that consist of cages separated by narrow windows, the inter-cage hopping of molecules occur practically independent of one another and, consequently, the diffusivities of pure components are the same as in the mixture. In sharp contrast, in MFI that consists of intersecting channels, the more mobile species is slowed down significantly in the mixture. [Copyright &y& Elsevier]