Geometrie analysis and scaling properties of calcite e-twins in the Cameros Basin (NW Iberian Chain, Spain)

One dimensional geometric analysis has been carried out in several scan lines from 885 measures of twins in calcite grains to determine grain width (in microns) and twin density (number of twins.mm-1 ) distributions. Grain width and twin density have a good fit to the log-normal frequency distribution. Twinning in calcite implies intracrystaline deformation mechanism with low shear stress. When the process begins low grain width and calcite twins are developed with a probably random distribution what could be supported by a negative exponential distribution tendency. The twinning process continues until a "critical" value of grain width and density which is going to influence in the scaling process, and becoming the distribution to log-normal type. But some data also conform to a power-law (fractal) frequency distribution from determined range or sizes (300 to WOO mm) and density (2 to W twins.mm-1) with some superimposed random (negative-exponential) elements, possible due to the irregularities at grain scale, but also because this systems show multifractal behavior

Organización lateral de monocapas mixtas

III Encuentro sobre Nanociencia y Nanotecnología de Investigadores y Tecnólogos Andaluce

Rootstock Effects on Leaf Photosynthesis in 'Navelina' Trees Grown in Calcareous Soil

Citrus crops in the Mediterranean region are often grown in high pH calcareous soils, which promote nutrient imbalances, especially iron deficiency. 'Navelina' trees grafted on eight different citrus rootstocks were assessed in terms of their relative tolerance to these soils. To do so, leaf gas exchange and chlorophyll a fluorescence parameters were measured for 2 consecutive years in leaves without visible injury symptoms. Trees were grown on the rootstocks Carrizo citrange, hybrids of Cleopatra mandarin x Poncirus trifoliata no. 5 (F-A 5),13 (F-A 13), and 16 (030116), Troyer citrange x common mandarin no. 18 (F-A 418), King mandarin x P. trifoliata no. 7 (F-A 517), 020324 (Troyer citrange x Cleopatra mandarin), and Volkamer lemon x P. trifoliata no. 64 (230164). gs and transpiration rate were clearly lower in leaves of shoots grafted on Carrizo citrange than in those on the other rootstocks assayed, but net photosynthetic flux did not differ. However, leaves of shoots on Carrizo citrange displayed a decline in their maximum quantum yield of PSII photochemistry [variable fluorescence/maximum fluorescence (F(v)/F(m)) ratio] and other chlorophyll parameters in the steady state such as photochemical quenching (qp) and the quantum efficiency of PSII photochemistry as well as an increase in nonphotochemical quenching (q(N)). Other rootstocks such as 030116, F-A 517 and, especially, F-A 5 showed the highest Phi(PSU) and F(v)/F(m) values, whereas F-A 5 had the lowest qN in the steady state. The photosynthetic characteristics observed in leaves on Carrizo citrange showed them to be the least tolerant to these calcareous conditions, whereas photosynthesis of 'Navelina' trees budded on F-A 5 were the most tolerant

Procedimiento para la selección de la estrategia de regulación más adecuada en estaciones de bombeo

[ES] La selección de la mejor estrategia de operación en una estación de bombeo que impulsa caudales directamente a red es un problema complejo de problema se puede plantear como la búsqueda de la mejor estrategia en una instalación ya existente (la mejora de un sistema que está en funcionamiento con posibilidades de instalar, por ejemplo, variadores de frecuencia en los equipos de la estación de bombeo y diseñar la estrategia de regulación más adecuada) o bien, directamente, como un problema de selección tanto de los equipos de bombeo como del sistema de regulación para una estación de bombeo a diseñar. Todo ello implica que en cada caso es necesario manejar un campo de soluciones excesivamente amplio, no conociendo la existencia de herramientas que, filtrando y acotando las soluciones posibles, aborden dicho problema teniendo en cuenta las variables más significativas: modelo de las bombas a instalar con sus curvas características, bombas de velocidad fija (BVF), número de bombas de velocidad variable (BVV), rendimiento mínimo aceptable, velocidad mínima y máxima de giro de las bombas, tarifas eléctricas, caudales a impulsar, etc. Debido a esto, el técnico se ve obligado a técnica que acote el número de soluciones. Al actuar de esta forma es posible que en muchos casos se desestimen soluciones atractivas desde el punto de vista energético y económico.Gómez Pajares, P.; García-Serra García, J.; Soriano Olivares, J.; Giner González, C. (2015). Procedimiento para la selección de la estrategia de regulación más adecuada en estaciones de bombeo. Universidad de Córdoba. 1191-1202. http://hdl.handle.net/10251/141658S1191120

Determinación de valores absolutos de paleoesfuerzos, basados en el maclado de la calcita, en el frente norte de la Sierra de Cameros (Cordillera Ibérica).

Calcite e-twin density (twins/mm) and percentage of calcite grains with one and two twin sets from sparry grains that fill microveins were used to precise the differential stress related with the inversion of the Cameros Basin, a Mesozoic sedimentary basin located in the northwestern part of Iberian Chain (Spain). The results obtained using techniques based on the percentage of twined grains yield better results that those techniques based on twin density. The deduced stress magnitudes fit well with the differential stress interval proposed for fold-thrust belt domains. Combination of twin data with rock mechanics data provides adequate estimations of differential stresses

One-dimension cubic-quintic Gross-Pitaevskii equation in Bose-Einstein condensates in a trap potential

By means of new general variational method we report a direct solution for the quintic self-focusing nonlinearity and cubic-quintic 1D Gross Pitaeskii equation (GPE) in a harmonic confined potential. We explore the influence of the 3D transversal motion generating a quintic nonlinear term on the ideal 1D pure cigar-like shape model for the attractive and repulsive atom-atom interaction in Bose Einstein condensates (BEC). Also, we offer a closed analytical expression for the evaluation of the error produced when solely the cubic nonlinear GPE is considered for the description of 1D BEC.Comment: 6 pages, 3 figure

Auditoría energética de estaciones de bombeo. Caso de estudio

[ES] El objetivo principal de este estudio es optimizar el funcionamiento de una estación de bombeo, lo que repercutirá directamente en una disminución de los costes de explotación. Para ello, se establecen los siguientes objetivos: - Analizar los flujos energéticos y pérdidas asociadas a cada transformación. - Identificación de los puntos de mejora de rendimiento. - Declaración de escenarios alternativos al actual. - Evaluación y valoración de los ahorros de los escenarios alternativos.Giner González, C.; Gómez Pajares, P.; Sanz Tarrega, F.; García-Serra García, J.; Soriano Olivares, J. (2020). Auditoría energética de estaciones de bombeo. Caso de estudio. 641-654. http://hdl.handle.net/10251/138452S64165

Enhanced error estimator based on a nearly equilibrated moving least squares recovery technique for FEM and XFEM

In this paper a new technique aimed to obtain accurate estimates of the error in energy norm using a moving least squares (MLS) recovery-based procedure is presented. We explore the capabilities of a recovery technique based on an enhanced MLS fitting, which directly provides continuous interpolated fields, to obtain estimates of the error in energy norm as an alternative to the superconvergent patch recovery (SPR). Boundary equilibrium is enforced using a nearest point approach that modifies the MLS functional. Lagrange multipliers are used to impose a nearly exact satisfaction of the internal equilibrium equation. The numerical results show the high accuracy of the proposed error estimator

Diseño de la asignatura Trabajo Fin de Grado en Geología (Facultad de Ciencias, UA)

Con la implantación en el año académico 2013-14 del cuarto y último curso del grado en Geología en la Universidad de Alicante, se ha implementado la asignatura obligatoria de Trabajo Fin de Grado en Geología (TFGG) con el objetivo de que el estudiante demuestre las competencias adquiridas durante sus estudios de geología, tanto las específicas de la titulación, como las competencias generales o transversales, tal como son las ligadas a la búsqueda y organización de documentación, a la redacción clara y concisa de una memoria escrita que recoja un trabajo original del alumno y a la presentación en público de su trabajo de manera clara y adecuada. Siguiendo las directrices que se establecen, tanto en la Facultad de Ciencias, como en la Universidad de Alicante se ha diseñado una asignatura Trabajo Fin de Grado con varias modalidades o líneas de actividad docente. Se ha constituido una Comisión de Trabajo de Fin de Grado en Geología (CTFGG) con el propósito principal de organizar y supervisar la asignación, seguimiento y evaluación de los trabajos

Disentangling the mechanisms shaping the surface ocean microbiota

BACKGROUND: The ocean microbiota modulates global biogeochemical cycles and changes in its configuration may have large-scale consequences. Yet, the underlying ecological mechanisms structuring it are unclear. Here, we investigate how fundamental ecological mechanisms (selection, dispersal and ecological drift) shape the smallest members of the tropical and subtropical surface-ocean microbiota: prokaryotes and minute eukaryotes (picoeukaryotes). Furthermore, we investigate the agents exerting abiotic selection on this assemblage as well as the spatial patterns emerging from the action of ecological mechanisms. To explore this, we analysed the composition of surface-ocean prokaryotic and picoeukaryotic communities using DNA-sequence data (16S- and 18S-rRNA genes) collected during the circumglobal expeditions Malaspina-2010 and TARA-Oceans. RESULTS: We found that the two main components of the tropical and subtropical surface-ocean microbiota, prokaryotes and picoeukaryotes, appear to be structured by different ecological mechanisms. Picoeukaryotic communities were predominantly structured by dispersal-limitation, while prokaryotic counterparts appeared to be shaped by the combined action of dispersal-limitation, selection and drift. Temperature-driven selection appeared as a major factor, out of a few selected factors, influencing species co-occurrence networks in prokaryotes but not in picoeukaryotes, indicating that association patterns may contribute to understand ocean microbiota structure and response to selection. Other measured abiotic variables seemed to have limited selective effects on community structure in the tropical and subtropical ocean. Picoeukaryotes displayed a higher spatial differentiation between communities and a higher distance decay when compared to prokaryotes, consistent with a scenario of higher dispersal limitation in the former after considering environmental heterogeneity. Lastly, random dynamics or drift seemed to have a more important role in structuring prokaryotic communities than picoeukaryotic counterparts. CONCLUSIONS: The differential action of ecological mechanisms seems to cause contrasting biogeography, in the tropical and subtropical ocean, among the smallest surface plankton, prokaryotes and picoeukaryotes. This suggests that the idiosyncrasy of the main constituents of the ocean microbiota should be considered in order to understand its current and future configuration, which is especially relevant in a context of global change, where the reaction of surface ocean plankton to temperature increase is still unclear. Video Abstract