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Induction heating is commonly used in laboratory-scale facilities to replicate the heating conditions of the receiver tubes of concentrated solar power plants. This work aims at shedding light at the induction heating characteristics for such applications through the development of a multiphysics numerical model capable of replicating the experimental conditions of a molten salt loop locally heated by an induction heater. In the experiments, a stainless steel pipe is heated on its external surface by the induction heater, which is switched on and off during the experimental data acquisition while molten salts are continuously circulating in its interior. These conditions are replicated, for the first time, in a two-dimensional numerical domain fully coupling the electromagnetic and thermal physics, including thermally dependent material properties of the heated pipe. Once validated against the experiments, the numerical results revealed that the volumetric nature of the induction heating shall be considered for an accurate representation of the temperature profile inside the tube. As a novelty, different equivalent surface boundary conditions are presented and, despite the Gaussian-like behavior of the induction heating on the surface of the tube, the results indicate that there exists no equivalent wall boundary condition to fully replicate the temperature profile obtained with the induction heater. The effect of independently varying experimental parameters such as the geometry of the pipe (i.e., diameter and thickness) and its distance to the induction heating system is also evaluated. Using large diameters of the tube reduces the difference between the angular temperature profile obtained using induction heating and a simplified wall boundary condition. For small wall thicknesses, the induction heating is capable of penetrating along the whole thickness of the tube, the total heat generated in the volume of the tube being exposed to the counteracting effects of the volumetric generation and the enhancement of the heat dissipation by the molten salt, as both of them increase for small thicknesses. The distance of the inductor to the pipe wall appears to maintain the volumetric characteristics of the heating and only affects the induction heating magnitude and efficiency. ; This work has been funded by Programa de Atracción de Talento (Modalidad 2) de la Comunidad de Madrid (Spain) 2019-T2/AMB-15938 and the project RTI2018-096664-B-C21 (MICINN, FEDER/UE). Eduardo Cano-Pleite acknowledges support from the CONEX-Plus programme funded by Universidad Carlos III de Madrid and the European Union's Horizon 2020 programme under the Marie Sklodowska-Curie grant agreement No. 801538.

This paper presents the results of a 3-D numerical simulation of a freely bubbling fluidized bed, based on the Eulerian¿Lagrangian approach, using the software Barracuda (CPFD-Barracuda). The main results obtained were assessed in terms of frequency analysis, bubble pierced length, bubble size, bubble passage frequency and bubble velocity. The results obtained were also compared with experimental data obtained in a 3-D fluidized bed using pressure and optical probes, and with the numerical results using the more common Eulerian-Eulerian approach, implemented in the commercial software Fluent (TFM-Fluent). The results show that CPFD-Barracuda satisfactorily predicts the global behaviour of bubbling beds with a low computational cost, although it computes smaller bubble sizes and lower bubble velocities than TFM-Fluent and experiments. Additionally, the spectra of pressure and particle volume fraction obtained with CPFD-Barracuda resemble those from the experiments and the TFM-Fluent simulations, but with a larger contribution of lower frequencies. The peaks of the pressure spectra from CPFD-Barracuda are close to those from the experiments and the TFM-Fluent simulations, whereas those in the solid volume spectra seem to be underestimated by CPFD-Barracuda. The results also indicate that the particle fraction threshold value chosen to distinguish bubbles contours notably influences the results of the bubble characteristics, especially for TFM-Fluent, whereas CPFD-Barracuda is less sensitive to this threshold value. ; This work was partially funded by the Ministerio de Economía y Competitividad (Projects ENE2016-78908-R and RTI2018-096664- B-C21 (MICINN, FEDER/UE)) of the Spanish Government, the Regional Government of Castilla-La Mancha (project SBPLY/17/180501/000412) and the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) (RED2018-102431-T).

The solar tower receivers tend to experience rupture problems due to the high thermal gradients and the corrosion produced by the working fluid, typically solar salt. In this work we have developed a series of CFD simulations to study a new receiver design composed of bayonet tubes aimed to reduce the overheating the receiver in the most thermally demanded area. These simulations evaluate the thermal behavior of the tubes for different working fluids, i.e. molten salt, liquid sodium and supercritical CO2. The simulations show that, for all the working fluids analyzed, it is possible to reduce the high temperatures of the tube thanks to the asymmetries created when the bayonet tube has an eccentric configuration. Besides, the greatest reduction of temperature in bayonet tubes is achieved when the working fluid is liquid sodium due to its higher thermal conductivity. ; The authors would like to thank the financial support provided by the Spanish government through the project ENE2015-69486-R (MINECO / FEDER, UE).

Images from high dynamic range (HDR) scenes must be obtained with minimum loss of information. For this purpose it is necessary to take full advantage of the quantification levels provided by the CCD/CMOS image sensor. LinLog CMOS sensors satisfy the above demand by offering an adjustable response curve that combines linear and logarithmic responses. This paper presents a novel method to quickly adjust the parameters that control the response curve of a LinLog CMOS image sensor. We propose to use an Adaptive Proportional-Integral-Derivative controller to adjust the exposure time of the sensor, together with control algorithms based on the saturation level and the entropy of the images. With this method the sensor's maximum dynamic range (120 dB) can be used to acquire good quality images from HDR scenes with fast, automatic adaptation to scene conditions. Adaptation to a new scene is rapid, with a sensor response adjustment of less than eight frames when working in real time video mode. At least 67% of the scene entropy can be retained with this method. ; The work was carried out as part of the projects EXPLORE (TIN2009-08572) and SiLASVer (TRACE PET 2008-0131) funded by the Spanish National R&D&I Plan. It has also received funding from the Government of the Region of Murcia (Séneca Foundation)

This paper describes the experience of the Cartagena node in the 2015 edition of the EU-xCEL project, which was funded by the European Union's Horizon 2020 Research and Innovation Programme. EU-xCEL aims at fostering entrepreneurship awareness and training among young graduates, in Information and Communication Technologies as well as to strengthen the European entrepreneurship ecosystem. This paper outlines the development of the training week and the posterior virtual incubation phase, as well as the experience of running the program in Cartagena. Finally, we outline some conclusions drawn from the experience. ; This work has been developed in the context of the EUxCEL project, funded by European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No 644801. It has been partially supported by the "Research Programme for Groups of Scientific Excellence at Region of Murcia" of the Seneca Foundation (Agency for Science and Technology of the Region of Murcia – 19895/GERM/15). Diego Alonso thanks the Spanish Ministerio de Educación, Cultura y Deporte, Subprograma Estatal de Movilidad, Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016 for grant CAS14/00238.

This research was funded by Spanish Ministerio de Economia, Industria y Competitividad, grant number PCIN2017-098, and by Regional Government Junta de Andalucia with FEDER European contribution, grant number P18-RT-3786. ; The adsorption of retinol, niacinamide and glycolic acid active ingredients on the internal surface of halloysite in an aqueous environment was explored at the molecular level by means of calculations based on quantum mechanics and force fields from empirical interatomic potentials. These active ingredients are stably adsorbed on the internal surface of halloysite forming hydrogen bonds between the hydrogen, oxygen and nitrogen atoms with the hydroxyl groups of the inner surface of the halloysite. In addition, electrostatic interaction between these active ingredients with the water molecules was observed. Therefore, the theoretical results indicate that the adsorption of these active principles is favourable in the halloysite nanotube, which allows directing future experimental investigations for the development and design of retinol, niacinamide and glycolic acid with halloysite nanotubes systems, which may be topical formulations for skincare. ; Spanish Ministerio de Economia, Industria y Competitividad PCIN2017-098 ; Junta de Andalucia ; European Commission P18-RT-3786

This present article studies and chriticizes the building system and the developement of the theater and dance complex of Canal (Teatros del Canal, Madrid), designed by Juan Navarro Baldeweg, Principal Professor of Architectural Design at Madrid School of Architecture Polytechnic University. These theaters are being built in the center of Madrid city. The owner and developer of this complex is Canal de Isabel II (the water supply company of Madrid regional Government). The project consist in a three building complex, two theatres and a choreographic centre, put together by a back service block, each of them with it's own different building solutions. This article is the result of the work done during the term 2006-07 of the Seminar of "Industrialization of Building Process" that, under the direction of the Principal Professor Alfonso del Águila, takes place within the Ph. D. Program of the Department of Construction and Architectural Technology set in Madrid School of Architecture Polytechnic University. The work includes two different parts: the fi rst one, which introduces is a prologue written by Prof. Navarro and a general description of the building. The second part describes its different construction areas, ranging from the different structural solutions, the hung façades pretending to be theatre curtains, some aspects of the interior design, as acoustics, special furniture and fi nishes, not in a mere descriptive way, but also from a critical manner with the intention to be a consequence with didactical value for the students/ authors. ; El artículo que se presenta estudia y valora el sistema constructivo, y su desarrollo, de las obras de los Teatros del Canal, obra del Catedrático de Proyectos de la Escuela de Arquitectura de Madrid, Prof. Navarro Baldeweg, que se están llevando a cabo en Madrid, siendo la Promotora y Propietaria el Canal de Isabel II de la Comunidad Autónoma de Madrid. Se trata de un conjunto de tres edifi cios, dos teatros y un centro coreográfi co, cada uno con soluciones ...

This paper aimed to improve the electrochemical activity of a pitch-derived open-pore graphite foam (GF) by an electrochemical coating of reduced graphene oxide (RGO) and platinum particles without significantly affecting its 3D-structure. RGO was synthesized using cyclic voltammetry (CV) from a 3 g L−1 GO and 0.1 M LiClO4 solution. For the electrodeposition of Pt particles, an alternating current method based on electrochemical impedance spectroscopy (EIS) was used. A sinusoidal voltage from a fixed potential Ei was varied following a selected amplitude (ΔEac = ± 0.35 V) in a frequency range of 8 Hz ≤ fi ≤ 10Hz, where i = 500. This method proved its efficiency when compared to the traditional CV by obtaining more highly electroactive coatings in less synthesis time. For samples' characterization, physical measures included permeability, pressure drop, and nitrogen adsorption isotherms. The electrochemical characterization was performed by CV. The surface morphology and chemical composition were examined using field emission electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDX), respectively. RGO improved the electron transfer rate constant of GF, and a more homogeneous coating distribution of reduced size Pt particles was obtained. ; This research was funded by the Spanish Agencia Estatal de Investigación (AEI) and the European Union (FEDER funds) contracts (MAT2016-77742-C2-1-P, MAT2016-77742-C2-2-P).

L'intégration effective de la restauration écologique dans la gestion des espaces naturels nécessite la définition de zones et d'actions prioritaires. À grande échelle spatiale, les priorités sont généralement définies par les experts en termes de facteurs écologiques, en particulier en fonction de la distribution d'espèces ou de quelques services écosystémiques. Cependant, les décisions de gestion doivent faire face à différents habitats naturels et répondre aux multiples exigences et aspirations de la société. L'émergence de nouveaux outils pour mieux identifier et analyser les critères de priorité et déterminer les meilleures alternatives de gestion, en intégrant les perspectives écologiques et socio-économiques sont nécessaires. Nous avons développé une approche participative pour identifier les sites prioritaires de restauration dans une région de 224 472 ha dans la Démarcation de la forêt de Crevillent, dans le sud-est semi-aride de l'Espagne. Le défi était de développer une méthodologie rigoureuse mais accessible qui pourrait être extrapolée à d'autres régions. Une plate-forme de 88 parties prenantes a été invitée à identifier et à pondérer les critères prioritaires pour la restauration. Les parties prenantes ont identifié cinq groupes de critères correspondant aux environnements naturels et semi-naturels, aux environnements hautement anthropisés, aux fonctions de l'écosystème, aux processus à l'échelle du paysage et aux aspects socio-économiques et culturels. Le poids intégré des critères étudiés a montré que ceux liés aux environnements hautement anthropisés (décharges, bords des rivières, carrières abandonnées, cultures pluviales et cultures irriguées) et aux fonctions de l'écosystème (facteurs clés pour réduire le risque et la vulnérabilité aux feux de forêt, l'érosion, la pollution de l'eau) ont reçu la plus haute priorité, ainsi que pour les zones à forte valeur culturelle et ethnologique. En revanche, la priorité pour les environnements naturels et semi-naturels et les caractéristiques à l'échelle du paysage était plus faible. Nous discutons de ces résultats et de la possibilité d'utiliser ce protocole pour soutenir la prise de décision concernant les actions de restauration écologique dans ce paysage méditerranéen.

The effective integration of ecological restoration (ER) into land management requires the definition of priority areas and actions. At large spatial scales, priorities are commonly defined by experts in terms of ecological factors, particularly species distribution or a small set of ecosystem services. However, management decisions must deal with different habitats, and respond to society multiple demands and aspirations. New tools for identifying and analyzing priority criteria and determining best management alternatives, integrating ecological and socio-economic perspectives are needed. We developed a participatory approach to identify priority areas for restoration in a 224,472 Ha area in Crevillent Forest Demarcation, southeast semi-arid Spain. The challenge was to develop a rigorous yet accessible methodology that could be extrapolated to other regions. An 88-stakeholder platform was asked to identify and weight priority criteria for ER. Stakeholders identified five groups of criteria corresponding to natural and semi-natural environments, highly-humanized environments, criteria related to ecosystem functions, criteria related to landscape-scale processes, and socio-economic and cultural criteria. The integrated weight of the studied criteria showed that highly-humanized environments (landfills and waste dumps, river margins, unused quarries, rainfed crops, and irrigated crops) and criteria related to ecosystem function (key areas to reduce wildfire risk and vulnerability, key areas to reduce erosion, key areas to reduce water pollution) received the highest priority, together with areas with high cultural and ethnologic value. In contrast, the priority for natural and semi-natural environments and landscape-scale features was lower. We discuss these results and the feasibility of using this protocol to support decision making concerning ecological restoration actions in this Mediterranean landscape.

Some results on particle image velocimetry (PIV) in 2-D freely bubbling fluidized beds are presented. The PIV applications were used in order to determine the initial particle velocity of bubble eruptions. A two-dimensional non-reacting fluidized bed was constructed to measure the origin of the ejected particles and the initial particle velocity distribution, using coarse sand particles. The bubble ejection mechanism was observed taking into account the origin of particles ejected, the initial particle velocity distributions as well as the effect of other neighbor exploding bubbles. Our results show that the assumption of linear dependence of initial velocity with the angle predicts the velocity faithfully only for purely vertical-ascent bubbles. Measurements of ejection velocities show that initial velocities in the combined layer are higher than those of the particles in the nose of the leading bubble. Avoiding coalescence of bubbles at the bed surface can lead to less particle entrainment out of the bed and consequently to shorter fluidized beds ; The financial support from Ministerio de Ciencia y Tecnología of the Spanish Government is appreciated (project number DPI2002-02453) ; Publicado

[EN] In the present review we show a variety of biomass product transformations through catalysis by both bulk and supported heteropolycompounds. The biomass sources considered include carbohydrates, oils and fats, and terpenes as main starting material groups. The products obtained and their applications are presented. ; We thank CONICET (PIP 003), Agencia Nacional de Promocion Cientifica y Tecnologica (Argentina) (PICT 0406), and Universidad Nacional de La Plata for financial support. GPR and HJT are members of CONICET. MJC and SI thank to Spanish Government-MINECO through Consolider Ingenio 2010-Multicat project for financial support. ; Sanchez, LM.; Thomas, HJ.; Climent Olmedo, MJ.; Romanelli, GP.; Iborra Chornet, S. (2016). Heteropolycompounds as catalysts for biomass product transformations. Catalysis Reviews: Science and Engineering. 58(4):497-586. https://doi.org/10.1080/01614940.2016.1248721 ; S ; 497 ; 586 ; 58 ; 4

Since its approval, in 2007, the Spanish Law of Equality (LO 3/2007) has been the target of many scholars on gender issues. Those analyses (and those previous to the first observable results of the Spanish Law of Equality), have largely prioritized political representative institutions and political parties as the main arenas to assess the impact of the new regulation. Nevertheless, to make a comprehensive analysis of the increase and impact of the presence of women in contemporary democracies one cannot exclude the existence of many other crucial actors in our pluralist systems, such as business organizations.In this line, in order to widen the knowledge on the presence of women in Spanish contemporary democracy, as well as to further assess the impact of Spanish Law of Equality on the presence of women in economic and political life, our paper will look at the gender bias of the executive committees in the Spanish Chambers of Commerce and business associations during the period 20010-2012. By placing those actors at the front sight, we aim to contribute with new empirical insights to the current debate on this topic.

Polyaniline coated conducting fabrics have been obtained by chemical oxidation of aniline by potassium peroxydisulfate on polyester fabrics. Two different acids have been employed to carry out the synthesis (HCl and H 2SO 4), obtaining the best results of conductivity with the latter one. The conducting fabrics have been characterized chemically by means of Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), energy dispersive X-Ray (EDX) and X-ray photoelectron spectroscopy (XPS). The morphology of the coatings has been observed by means of scanning electron microscopy (SEM). The conducting properties of the fabrics have been measured by means of electrochemical impedance spectroscopy (EIS). The electrochemical characterization has been carried out by means of cyclic voltammetry (CV) and scanning electrochemical microscopy (SECM). The conducting fabrics have also shown electrochromic properties, changing its color from green yellowish at -1 V to dark green at +2 V. The durability of the coating has been evaluated by means of washing and rubbing fastness tests. © 2011 Elsevier Ltd. All rights reserved. ; Authors thank to the Spanish Ministerio de Ciencia e Innovacion and European Union Funds (FEDER) (contract CTM2010-18842-C02-02) and Universitat Politecnica de Valencia (Primeros Proyectos de Investigacion (PAID-06-10)) for the financial support. J. Molina is grateful to the Conselleria d'Educacio (Generalitat Valenciana) for the FPI fellowship. ; Molina Puerto, J.; Esteves, M.; Fernández Sáez, J.; Bonastre Cano, JA.; Cases Iborra, FJ. (2011). Polyaniline coated conducting fabrics. Chemical and electrochemical characterization. European Polymer Journal. 47(10):2003-2015. https://doi.org/10.1016/j.eurpolymj.2011.07.021 ; S ; 2003 ; 2015 ; 47 ; 10

2003 2015 47 10 ; S ; Polyaniline coated conducting fabrics have been obtained by chemical oxidation of aniline by potassium peroxydisulfate on polyester fabrics. Two different acids have been employed to carry out the synthesis (HCl and H 2SO 4), obtaining the best results of conductivity with the latter one. The conducting fabrics have been characterized chemically by means of Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), energy dispersive X-Ray (EDX) and X-ray photoelectron spectroscopy (XPS). The morphology of the coatings has been observed by means of scanning electron microscopy (SEM). The conducting properties of the fabrics have been measured by means of electrochemical impedance spectroscopy (EIS). The electrochemical characterization has been carried out by means of cyclic voltammetry (CV) and scanning electrochemical microscopy (SECM). The conducting fabrics have also shown electrochromic properties, changing its color from green yellowish at -1 V to dark green at +2 V. The durability of the coating has been evaluated by means of washing and rubbing fastness tests. © 2011 Elsevier Ltd. All rights reserved. Authors thank to the Spanish Ministerio de Ciencia e Innovacion and European Union Funds (FEDER) (contract CTM2010-18842-C02-02) and Universitat Politecnica de Valencia (Primeros Proyectos de Investigacion (PAID-06-10)) for the financial support. J. Molina is grateful to the Conselleria d'Educacio (Generalitat Valenciana) for the FPI fellowship. Molina Puerto, J.; Esteves, M.; Fernández Sáez, J.; Bonastre Cano, JA.; Cases Iborra, FJ. (2011). Polyaniline coated conducting fabrics. Chemical and electrochemical characterization. European Polymer Journal. 47(10):2003-2015. https://doi.org/10.1016/j.eurpolymj.2011.07.021