Suchergebnisse

11 páginas, 3 tablas, 5 figuras. ; The aim of this study was to gain insights on the potential hydrological and biogeochemical mechanisms controlling the response of two nested Mediterranean catchments to long-term changes in atmospheric inorganic nitrogen and sulphate deposition. One catchment was steep and fully forested (TM9, 5.9 ha) and the other one had gentler slopes and heathlands in the upper part while side slopes were steep and forested (TM0, 205 ha). Both catchments were highly responsive to the 45% decline in sulphate concentration measured in atmospheric deposition during the 1980s and 1990s, with stream concentrations decreasing by 1.4 to 3.4 μeq L−1 y−1. Long-term changes in inorganic nitrogen in both, atmospheric deposition and stream water were small compared to sulphate. The quick response to changes in atmospheric inputs could be explained by the small residence time of water (4–5 months) in these catchments (inferred from chloride time series variance analysis), which was attributed to steep slopes and the role of macropore flow bypassing the soil matrix during wet periods. The estimated residence time for sulphate (1.5–3 months) was substantially lower than for chloride suggesting unaccounted sources of sulphate (i.e., dry deposition, or depletion of soil adsorbed sulphate). In both catchments, inorganic nitrogen concentration in stream water was strongly damped compared to precipitation and its residence time was of the order of decades, indicating that this essential nutrient was strongly retained in these catchments. Inorganic nitrogen concentration tended to be higher at TM0 than at TM9 which was attributed to the presence of nitrogen fixing species in the heathlands. Our results indicate that these Mediterranean catchments react rapidly to environmental changes, which make them especially vulnerable to changes in atmospheric deposition. ; S.B. work was funded by the Spanish Research Council (JAE-DOC027) and the Spanish CICT (Juan de la Cierva contract JCI-2008-177). The financial support from the Spanish Government projects CGL2009-13188-C03-01, MED_FORESTREAM (CGL2011-30590) and MONTES-Consolider (CSD-2008-00040) is fully acknowledged. ; Peer reviewed

The objective of the Spanish government-funded project GESMO (Gestión integral del acuífero 08.29 Mancha Oriental), is to develop new tools for the evaluation and monitoring of water policies. These tools have to be capable of matching resource exploitation with reserve sustainability, applied to aquifer 08.29 in the Eastern Mancha, Spain. A decision support system (DSS), was developed as part of the GESMO project, that integrates two different systems within one computer application. One, an hydrogeological model, simulates the River Júcar basin and its associated aquifer. The other, an econometric system, is capable of predicting the evolution of regional crop maps, crop yields and crop prices, thus allowing the determination of the regional gross product of crops. This paper describes mainly the economic system of the DSS, a set of econometric models. Those used for crop allocations are the most important for the DSS. The approach followed for the specification of the DSS is proposed as a provisional method based on information from the pre-quota period to estimate likely responses of farmers in a post-quota period. A brief description of the overall structure of the DSS and an example of one of its possible applications are also included in the paper. ; El objetivo del proyecto GESMO (Gestión integral del acuífero 08.29 Mancha Oriental) financiado por el gobierno español, consiste en desarrollar nuevas herramientas para la evaluación y el seguimiento de las políticas del agua. Dichas herramientas deben ser capaces de adecuar la explotación de recursos a la reserva sostenible, aplicándolo al acuífero 08.29 de la Mancha Oriental, España. Como parte del proyecto GESMO se ha desarrollado un sistema de soporte a la decisión (DSS), que integra dos sistemas distintos en una aplicación informática. Uno de ellos consiste en un modelo hidrogeológico que simula la cuenca del río Júcar y su acuífero asociado. El otro es un sistema econométrico capaz de predecir la evolución del mapa regional de cultivos, el rendimiento de las cosechas y sus precios, todo ello encaminado al cálculo del producto regional bruto de los cultivos. Este artículo describe principalmente el sistema económico del DSS, formado por un conjunto de modelos econométricos. Los más importantes para el DSS son los que se utilizan para la asignación de cultivos. La aproximación seguida para su especificación se propone como una solución provisional al problema de la estimación de respuestas probables de los agricultores en un período postcuota, basándose en la información proporcionada por el periodo pre-cuota. Se incluyen también en este artículo una breve descripción de la estructura completa del DSS y un ejemplo de una de sus posibles aplicaciones.

10 pages, 1 figure, 1 table, 60 references.-- Trabajo publicado en la Section 2: Country Reports.-- El volumen consta de 202 páginas.-- Meeting at Soil Survey and Land Research Centre Cranfield University, Silsoe, UK., que tuvo lugar del 21-22, abril, 1998. ; Meetings of European Union Heads of Soil Survey Organisations were held in 1989 and 1994 respectively. Both were followed by publication of monographs describing the state-of-the-art in each of the member countries (Hodgson 1991; Le Bas & Jamagne 1996). Limited progress has been made in Spain since then, except for a proposal for an ambitious macroproject (PNCTA), the prospects for which now seem somewhat uncertain. Readers interested in historical aspects of Spanish pedology and/or soil mapping can refer to studies by Díaz Fierros (1979 and 1997) Mudarra (1989 and 1994); Sunyer (1996), Ibáñez el al. (1991, 1997), Boixadera and Ibáñez, (1996) and Guerra, (1997). This paper describes progress in soil survey from 1994 to 1998 and provides additional information on monitoring and soil databases developed in Spain. Nevertheless, some Spanish soil databases arising from some initiatives in Pan-European programmes are not included in the discussion here due to their particular scope. The Spanish contribution to the ICP Forest programme, recently published on a CD-ROM that holds morphological, taxonomic and analytical information corresponding to 453 soil profiles, is a case in point (Montoya & López-Arias, 1998). ; Peer reviewed

This work investigates commercially available granular phase change materials (PCMs) with different transition temperatures for the use of thermal-energy storage systems in fluidized beds. The hydrodynamic characteristics of granular PCMs were tested in cylindrical-3D and planar-2D fluidized beds. The density, particle size distribution and angle of repose were measured for various PCM materials. Further attrition studies were conducted with changes in particle surface from abrasion, which were characterized using a Scanning Electron Microscope (SEM). The results indicate that some materials with smaller particle size and thinner supporting structure can lose the paraffin during the fluidization process, when paraffin is in a liquid state. As a consequence, the particles agglomerate, and the bed defluidizes. For all of the tested materials, only GR50 (with a transition temperature of 50 °C) properly fluidizes when the paraffin is in the liquid state and has shown to endure >75 h of continuous operation and 15 melting-solidification cycles in a fluidized bed. Additional differential scanning calorimetry (DSC) measurements of the cycled particles did not show a decrease in energy storage capacity of the granular PCM, which corroborates that there is no loss of material after >75 h of fluidization. ; The work is partially funded by the Spanish government (ENE2010-15403, ENE2011-22722 and ENE2015-64117-C5-1). The authors would like to thank the Catalan Government for the quality accreditation to their research groups GREA (2014 SGR 123). The study that led to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n°n°PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 657466 (INPATH-TES).

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Physical Chemistry C, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.jpcc.6b06049 ; We report a study of the structural, vibrational, and electronic properties of layered monoclinic arsenic telluride (α-As2Te3) at high pressures. Powder X-ray diffraction and Raman scattering measurements up to 17 GPa have been complemented with ab initio total-energy, lattice dynamics, and electronic band structure calculations. Our measurements, which include previously unreported Raman scattering measurements for crystalline α-As2Te3, show that this compound undergoes a reversible phase transition above 14 GPa at room temperature. The monoclinic crystalline structure of α-As2Te3 and its behavior under compression are analyzed by means of the compressibility tensor. Major structural and vibrational changes are observed in the range between 2 and 4 GPa and can be ascribed to the strengthening of interlayer bonds. No evidence of any isostructural phase transition has been observed in α-As2Te3. A comparison with other group 15 sesquichalcogenides allows understanding the structure of α-As2Te3 and its behavior under compression based on the activity of the cation lone electron pair in these compounds. Finally, our electronic band structure calculations show that α-As2Te3 is a semiconductor at 1 atm, which undergoes a trivial semiconducting−metal transition above 4 GPa. The absence of a pressure-induced electronic topological transition in α-As2Te3 is discussed. ; This work has been performed under financial support from Projects MAT2013-46649-C4-2-P, MAT2013-46649-C4-3-P, MAT2015-71070-REDC, FIS2013-48286-C2-1-P, and FIS2013-48286-C2-2-P of the Spanish Ministry of Economy and Competitiveness (MINECO), and the Department of Education, Universities and Research of the Basque Government and UPV/EHU ...