Drop tower setup to study the diffusion-driven growth of a foam ball in supersaturated liquids in microgravity conditions

The diffusion-driven growth of a foam ball is a phenomenon that appears in many manufacturing process as well as in a variety of geological phenomena. Usually these processes are greatly affected by gravity, as foam is much lighter than the surrounding liquid. However, the growth of the foam free of gravity effects is still very relevant, as it is connected to manufacturing in space and to the forma- tion of rocks in meteorites and other small celestial bodies. The aim of this research is to investigate experimentally the growth of a bubble cloud growing in a gas-supersaturated liquid in microgravity conditions. Here, we describe the ex- periments carried out in the drop tower of the Center of Ap- plied Space Technology and Microgravity (ZARM). In few words, a foam seed is formed with spark-induced cavitation in carbonated water, whose time evolution is recorded with two high-speed cameras. Our preliminary results shed some light on how the size of the foam ball scales with time, in particular at times much longer than what could be studied in normal conditions, i.e. on the surface of the Earth, where the dynamics of the foam is already dominated by gravity after several milliseconds

Autotraducción y biliterariedad en el espacio ibérico: el caso gallego

La autotraducción es, sin duda, un fenómeno privilegiado para el estudio de los límites conceptuales que adquieren las formas identitarias. Dentro del espacio ibérico, entendido como una comunidad interliteraria específica, nuestro análisis de los escritores gallegos que se versionan al castellano demuestra la ambivalencia de un proceso que puede ser observado tanto como un modo de marginalización de la literatura periférica como como una vía de resistencia y afirmación de la alteridad lingüística y cultural. En último término, lo que proporcionará visibilidad a la cultura minorizada será no tanto el hecho de explicitar paratextualmente el verdadero origen de la versión, sino la proyección binacional (y no solo biliteraria) del autor. Sin embargo, tal como comprobamos, la habitual disociación entre  biliterariedad y binacionalidad enfrenta al autor periférico peninsular a una contradicción por el momento irresoluble.Self-translation is undoubtedly a privileged phenomenon to study the conceptual boundaries that acquired forms of identity. Within the Iberian context, considered as a particular interliterary community, our analysis of the Galician writers who are versioned into Castilian, demonstrates the ambivalence of a process that can be seen both as a way of marginalization peripheral literature as a means of resistance and assertion of linguistic and cultural otherness. Eventually, this which will provide visibility to the minority culture is not really the fact of explaining paraliterally the true origin of the version, but the binational projection and not just biliterary of the author

Macroporous silicon for high-capacitance devices using metal electrodes

Peer ReviewedPostprint (published version

Experimental development and modeling of a membrane reactor for the direct synthesis of DME with CO2 valorization.

265 p.Se ha estudiado la síntesis directa de dimetil éter (DME) a partir de sistemas H2+CO+CO2, con un reactor de membrana de lecho fijo (PBMR). El trabajo experimental para el diseño y puesta a punto del reactor ha consistido en las siguientes etapas: selección del material adecuado para la membrana en base a su caracterización; puesta a punto de un método reproducible de cristalización de la membrana sobre un soporte metálico; configuración del sistema reactor-membrana en el laboratorio; adecuación del equipamiento de análisis cromatográfico al nuevo sistema experimental.En base a los resultados se ha evaluado la mejora de las prestaciones respecto al reactor convencional (PBR), justificables por la alteración del equilibrio termodinámico debido a la permselectividad de los componentes del medio de reacción y consiguiente cambio de composición en el reactor.El catalizador utilizado ha sido de CuOZnOZrO2/SAPO-11, y ha sido caracterizado por diferentes técnicas: adsorción-desorción de N2; microscopio de barrido (SEM); espectroscopia de emisión óptica de plasma acoplado inductivamente (ICP-OES); difracción de rayos X (XRD); reducción a temperatura programada (TPR); quimisorción TPR/N2O; desorción a temperatura programada (TPD) de NH3; termogravimetría/calorimetría de la adsorción diferencial de NH3. Su comportamiento en el intervalo de condiciones antes descrito para el PBMR ha sido cuantificado con un modelo cinético que considera lasetapas individuales del esquema de reacción (síntesis de metanol y DME desde CO y CO2, deshidratación de metanol a DME y reacción water gas shift (WGS)), así como la desactivación del catalizador (principalmente con deposición de coque).Se ha establecido un original modelo matemático para la simulación del reactor de membrana, con la membrana LTA seleccionada. El modelo de simulación considera las ecuaciones del modelo cinético y las ecuaciones de transporte de materia para cada componente entre las regiones de reacción y permeado. Este modelo se ha utilizado en primer lugar, para determinar las propiedades de transporte en la membrana, mediante experimentos sin catalizador en la región de reacción. En segundo lugar, y utilizando los parámetros cinéticos y de transporte en la membrana, previamente calculados, se ha realizado la simulación del PBMR, evaluando las ventajas de este reactor respecto al PBR para la producción de DME y oxigenados (DME y metanol) y mostrando la capacidad del propio modelo de simulación para estudios de aumento de escala y para futuros estudios de optimización de estrategias de barrido y recirculación

Development and validation of the Scale of Motives for Using Social Networking Sites (SMU-SNS) for adolescents and youths

Over the past decade, the Uses and Gratifications theory has driven research on the motives behind social media use. The three most commonly explored motives have been: maintaining relationships, seeking information, and entertainment. The aim of this study was to develop and validate the Scale of Motives for Using Social Networking Sites (SMU-SNS), a measure to assess a wider range of motives for using Social Networking Sites than have previously been researched. A multi-method design with different samples of high-school and university students was used. First, to develop the pool of items, a literature review and a focus group study (n = 48, age range = 16–21) was conducted. Second, to reduce and refine the pool of items a pilot study (n = 168, age range = 14–24) was performed. Third, a validation study (n = 1102, age range = 13–25) was conducted to assess the validity and reliability of the SMU-SNS. Cross-validation using EFA and CFA resulted in a final version comprising 27 items distributed in nine factors (Dating, New Friendships, Academic Purposes, Social Connectedness, Following and Monitoring Others, Entertainment, seeking Social Recognition, Self-expression, and seeking Information). Internal consistency was excellent and evidence of measurement invariance across gender and age was largely achieved. The SMU-SNS scores significantly correlated with other relevant variables, including age, gender, certain personality traits, social support, loneliness, and life satisfaction. Overall, findings supported the SMU-SNS as a valid and reliable measure to assess youth’s motives for using Social Networking Sites. Psychometric and general implications are discussed.Ministerio de Economía y CompetitividadMinisterio de Educación y Formación Profesiona

Results of the implementation of the System for the Integrated Assessment of Protected Areas (SIAPA) to the protected areas of the Autonomous Region of Madrid (Spain)

The long-term conservation of biodiversity and related ecosystems goods and services of the Autonomous Region of Madrid is jeopardized by the intensive resource-consuming development model followed by the region in the past few decades. This paper presents the aggregated results of the first integrated assessment of the protected areas of the Autonomous Region of Madrid (Spain) with the System for the Integrated Assessment of Protected Areas (SIAPA). Detailed results are also provided for individual protected areas as supplementary data. The assessment was done during 2009–2010, on ten protected areas differing in their sizes (from 2.5 to 52,796 ha), protection categories (seven categories) and types of ecosystems present. Comparison of results from both assessment models of the SIAPA (the Complete Model and the Simplified Model) is also presented. The results from the Complete Model show that eight out of the ten protected areas of the Autonomous Region of Madrid are currently ineffective. The poorest partial indexes overall were: “State of Conservation” and “Social and Economic Context”. The only indexes significantly correlated with the effectiveness of a protected area were: the “State of Conservation” (r = 0.851**) and the “Social Perception and Valuation” (r = 0.786**). Although not as relevant as was thought, “Management” and the other non-significant factors are likely to influence the effectiveness of protected areas as well. The results for the Simplified Model are slightly better than those for the Complete Model, although this is probably a specific result of this assessment. The two models of the SIAPA were very significantly correlated, although their aggregated results should not be compared directly.Peer reviewe

Proposal of a system for the integrated and comparative assessment of protected areas

Appendix A: Supplementary data http://dx.doi.org/10.1016/j.ecolind.2012.05.009Protected areas’ overall goal is to achieve the long-term conservation of natural and associated cultural goods and services. However, effective long-term conservation of natural and associated cultural resources cannot always be guaranteed by a protection regime or even by effective management, as it is usually assumed. The ultimate goal of assessing protected areas is therefore concerned less with management effectiveness than with their overall long-term effectiveness. This paper describes the methodology underpinning the System for the Integrated Assessment of Protected Areas (SIAPA). The aim of SIAPA is to make the concept of ‘effectiveness’ operational when applied to protected areas. It is an innovative, horizontal site-level assessment system for evaluating integrally and comparably the effectiveness of terrestrial protected areas, as the assessment is based on the same parameters. Indicators are the basic assessment units. They were weighted by an expert panel and integrated into six categories (indexes) defining the effectiveness of protected areas: state of conservation, planning, management, social and economic context, social perception and valuation, and threats to conservation. These indexes were subsequently integrated into a single super-index: an effectiveness index for the protected area. Two alternative models of the SIAPA were developed: the complete model, containing 43 indicators, in order to maximize the amount of information on each protected area; and the simplified model, containing 28 indicators, in order to maximize the cost-effectiveness of the assessment.Peer reviewe