Low-temperature electrocatalytic conversion of CO2 to liquid fuels: effect of the Cu particle size

A novel gas-phase electrocatalytic system based on a low-temperature proton exchange membrane (Sterion) was developed for the gas-phase electrocatalytic conversion of CO2 to liquid fuels. This system achieved gas-phase electrocatalytic reduction of CO2 at low temperatures (below 90 °C) over a Cu cathode by using water electrolysis-derived protons generated in-situ on an IrO2 anode. Three Cu-based cathodes with varying metal particle sizes were prepared by supporting this metal on an activated carbon at three loadings (50, 20, and 10 wt %; 50% Cu-AC, 20% Cu-AC, and 10% Cu-AC, respectively). The cathodes were characterized by N2 adsorption–desorption, temperature-programmed reduction (TPR), and X-ray diffraction (XRD) and their performance towards the electrocatalytic conversion of CO2 was subsequently studied. The membrane electrode assembly (MEA) containing the cathode with the largest Cu particle size (50% Cu-AC, 40 nm) showed the highest CO2 electrocatalytic activity per mole of Cu, with methyl formate being the main product. This higher electrocatalytic activity was attributed to the lower Cu–CO bonding strength over large Cu particles. Different product distributions were obtained over 20% Cu-AC and 10% Cu-AC, with acetaldehyde and methanol being the main reaction products, respectively. The CO2 consumption rate increased with the applied current and reaction temperature

Effects of nodular extracts of Alnus glutinosa (L.) Gaertn. on nitrogen fixation (Acetylene reduction assay) and denitrification in different soils

European alder (Alnus glutinosa [L.] Gaertn) nodules were maintained under conditions that allow their exudation (water stress). The effect of this nodular extracts colected on free nitrogen fixation (acetylene reduction assay [ARA]) and denitrification, was evaluated in three soils of significativelydifferent physico-chemicalcharacteristics. The comparisons with controls having different concentrations of glucose as carbon source suggest that, in the assayed conditions, the nodular european alder extracts activate ARA (up to 9.97% respect water control) and produces a partial inhibition of denitrification. The effects do not seem to be due neither to organic carbon nor to nitrate, but rather to specific activator(s) and inhibitor(s) of the processes considered.Nódulos radicales de aliso europeo [Alnusglutinosa (L.)Gaertn.] fueron mantenidos en condiciones que optimizan el proceso de exudación (estrés hídrico). Se evaluó el efecto de dichos extractos sobre la fijación libre de nitrógeno (ARA) y desnitrificación en tres suelos con diferencias significativas en sus características físico-químicas. Las comparaciones con diferentes controles, muestran que los extractos activan (en un 9.97%) el ARA y promueven una inhibición parcial de la desnitrificación. Los efectos no parecen causados por el aporte de carbono orgánico o de nitrato por parte de los exudados, sino por algún activador o inhibidor especifico de los procesos considerados

Electrochemical Activation of Ni Catalysts with Potassium Ionic Conductors for CO2 Hydrogenation

Three different kind of Ni-based catalysts were prepared on a K-β″Al2O3 solid electrolyte by combining the annealing of an organometallic paste and the addition of a catalyst powder. The different catalysts films were tested in the CO2 hydrogenation reaction under electrochemical promotion by K+ ions, and were characterized by XRD and SEM. The catalyst film derived from the addition of an α-Al2O3 powder to the Ni catalyst ink presented the highest catalytic activity as a result of the increase in Ni catalyst film porosity. The influence of the applied potential and other operation variables were evaluated on the Ni catalytic activity and selectivity. Hence, the CO production rate was enhanced either by decreasing the applied potential (with the consequent supply of K+ ions to the catalyst surface) or by increasing the CO2 (electron acceptor) feed concentration. On the other hand, CH4 production rate was favoured at positive potentials (removing K+ from the catalyst surface) or by increasing the H2 (electron donor) feed concentration. The global CO2 consumption rate increased upon negative polarization in all experiments and the electrochemical promotion of catalysis effect showed to be reversible and reproducible. Hence, the electrochemical promotion phenomena demonstrated to be a very useful technique to in situ modify and control the catalytic activity and selectivity of a non-noble metal such as Ni for the production of CH4 or syngas via CO2 valorization.Es la versión preprint del artículo. Se puede consultar la versión final en https://doi.org/10.1007/s11244-015-0488-

Direct production of flexible H2/CO synthesis gas in a solid electrolyte membrane reactor

The development of novel configurations for the production of synthesis gas (syn-gas) of flexible H2/CO ratio is of great importance to reduce the cost for the synthesis of synfuels and high-value chemicals. In this work, we propose a radically novel approach to the direct production of syn-gas with flexible H2/CO ratio based on the solid electrolyte membrane reactor (SEMR). For that purpose, a single-chamber solid electrolyte membrane reactor based on yttria-stabilized zirconia (YSZ) has been developed (Pt/YSZ/Pt), where both active Pt catalysts–electrodes were exposed to the same reaction atmosphere (C2H5OH/H2O = 0.7 %/2 %). The application of different polarizations at temperature range (600–700 °C) allows to control the H2/CO ratio of the obtained syn-gas, i.e., the ratio was varied between 1.5 and 12 under polarization conditions. Unlike conventional catalytic partial oxidation processes, the H2/CO adjustment was managed without the requirement of external O2 feeding to the reactor. An increase in the applied current or potential caused the H2/CO ratio to increase vs. the open-circuit conditions where ethanol reforming occurred on the Pt catalyst–electrodes which is due to an increase in the rate of the electro-catalytic processes. On the other hand, a decrease in the H2/CO ratio at a fixed potential was achieved at higher temperatures due to the further reaction of the produced H2 with the rest of the species present in the gas phase, leading to a decrease in the faradaic efficiency. The proposed configuration may be of great interest especially for biorefinery applications where H2, syn-gas and electricity may be produced from bioethanol.Es la versión preprint del artículo. Se puede consultar la versión final en https://doi.org/10.1007/s10008-015-2922-

Electrochemical reforming vs. Catalytic reforming of ethanol: A process energy analysis for hydrogen production

This work reports an energetic analysis for hydrogen production via catalytic steam and electrochemical ethanol reforming processes. For both systems, a complete flow diagram process was proposed and simulated by Aspen HYSYS according to literature data. Besides hydrogen, other byproducts such as acetaldehyde (electrochemical reforming) and ethylene and methane (catalytic reforming) were also considered. The energy requirement of the different process units was calculated according to the operating parameters. Just process energy (thermal energy and electrical energy) consumption was considered in the study of the steam reforming whereas both energy process and electrical energy consumption were considered in the study of the electrochemical reforming. Material balances revealed electrochemical reforming to present higher hydrogen yields. (0.0436 vs. 0.0304 kg H2/kg C2H5OH of the classical catalytic reforming). In addition to its higher simplicity, simulation results showed a lower energy consumption in the H2 production by the electrochemical approach (29.2 vs. 32.70 k Wh/Kg of H2). These results demonstrated the interest of the electrochemical reforming of ethanol to obtain high purity hydrogen in a single reaction/separation step, thereby representing an interesting alternative to classical catalytic reforming.Es la versión preprint del artículo. Se puede consultar la versión final en https://doi.org/10.1016/j.cep.2015.05.00

Fish abundance estimation with imaging sonar in semi-intensive aquaculture ponds

To know the abundance of fishes and their size distribution in the semi-intensive rearing systems in traditional ponds is an aspect key to plan and manage efficiently the sales lots. Usually this information is obtained by means of sampling which mandatory supposes a direct catch and stressful and time consuming management of fishes. Therefore, in this work we propose the use of non-invasive procedures based on multibeam sonars or imaging sonars to count and size the fishes in the ponds. For that, we use a commercial technology portable-fixed multibeam imaging sonar and estimate the abundance in ponds of a gilt-head seabream (Sparus aurata) fishfarm from sonar image analysis and adapting statistical methodologies traditionally applied for bird abundance estimation. Additionally, a simulation software was developed to emulate the fish aggregation contained in the rearing ponds. This computer program allows the calculation of an abundance correction factor which depends on the transducer beam size in relation to the pond size. The results indicate that the estimation is as accurate as the obtained by the fishfarm manager using traditional sampling methods and additionally it is possible to obtain a realistic function of the size distribution which allows estimate the biomass by size contained in the rearing ponds.This work was supported by KTTSeaDrones project (0622_KTTSEADRONES_5_E), cofunded by the European Regional Development Fund, ERDF, through the Interreg V-A Spain-Portugal program (POCTEP) 2014–2020. We would like to express our gratitude to Rafael Rodríguez Sierra (Manager of ‘Salinas del Astur’) for his willingness to carry out all the experiments of the KTTSeaDrones project at the ‘Salinas del Astur’ facilities. Funding for open access charge: Universidad de Huelva/ CBUA

Fases de implementación de Blended Learning en las universidades españolas. Estudio basado en análisis de segmentación

[ES] El objetivo principal de este estudio es conocer y describir las fases de adopción de la modalidad formativa denominada Blended Learning (Blearning). Se aplicó una encuesta a 980 profesores de universidades públicas de todo el estado español. El análisis de los datos se realizó mediante técnicas de clustering para la agrupación de los sujetos (análisis de segmentación mediante el algoritmo CHAID). Los resultados ofrecen claves para comprender por qué los docentes universitarios adoptan o no esta modalidad de enseñanza, identificando perfiles o rasgos que caracterizan cada uno de los subgrupos agrupados en cada una de las fases de adopción (tomadas como variables criterio), en función de una serie de características personales y profesionales (Sexo, Edad; Categoría profesional, Área de conocimiento, Experiencia docente, Actitud hacia Blearning, Nivel de Autoeficacia), y variables contextuales relacionadas con formación recibida sobre Blended Learning en la universidad. Todas ellas variables predictoras. De manera indirecta, este conocimiento sobre las fases de adopción puede aportar información sobre el estadio de difusión institucional de la metodología B-learning en el conjunto de la universidad española

Health gerontechnology in ageing: a quantitative study

[EN] Over the last decade there has been a significant rise in Information and Communication Technologies [ICT] use among the elderly. Various recent studies highlight the benefits that ICT can provide to the elderly in terms of improvements to both mental and physical health, self-health assessment, satisfaction and quality of life, a reduction in the perception of loneliness, or favourable health behaviours. However, there are also reports that indicate that this age group continues to experience an equally significant digital exclusion. Researchers such affirm that use and access to digital technologies by older people is measured by different key factors that impinge on this digital divide such as level of education and/or income, gender, existence of any disabilities, place of residence, and even civil status. In response to the reduction of this digital divide, gerontechnology plays a fundamental role in this area. Gerontechnology can be defined as an interdisciplinary field that connects existing technologies and those that are developing with the aspirations and needs of the elderly, supporting in this way successful ageing. In this respect, the literature on this subject establishes that this new professional field, or applied discipline, presents five areas of study: living environments, communication, personal mobility and transportation, self-fulfilment and health. Specifically, our study focuses on this last area, which focuses on the development of technological devices geared towards preventing particular behaviours that are harmful to health and on improving the quality of life of those of an advanced age. Thus, this study has two main aims: on the one hand, to analyse the control that this age group possesses over the gerontechnology of health and, and on the other hand, the importance of its use to control various aspects of health and wellbeing. For this research a quantitative study was used, with a sample of 383 people from Castile and Leon [Spain] over the age of 60. A questionnaire designed according to the research aims was used in order to collect the data. The tool was divided into three sections: the first was aimed at collecting sociodemographic data, the second was made up of items to collect information on control over devices geared towards the area of health; and lastly, the third was aimed at studying the importance of using devices geared towards the monitoring of various aspects of health and wellbeing among the elderly. The data obtained was then analysed through the application of descriptive tests. The initial results of this study show that the majority of those surveyed are familiar with, but have never used the devices or apps geared towards health or for its monitoring. In spite of this tendency, the majority do recognise the importance of controlling aspects related to health and wellbeing through the use of technological devices. In both situations, differences regarding the age range of the participants can be noted. As a conclusion to this work, we highlight the existence of a digital divide among this age group. Therefore, we deem it necessary to expand this research with regard to the implementation and use of ICT among the elderly, providing innovative spaces where this age group can participate in an active way on the design, co-creation and assessment of efficient and useful products that are adapted to the needs of the end users

Evaluation of LIRIC Algorithm Performance Using Independent Sun-Sky Photometer Data at Two Altitude Levels

The authors thank the FEDER program for the instrumentation used in this work and the University of Granada for supporting this study through the Excellence Units Program “Plan Propio. Programa23 Convocatoria 2017”. CIMEL Calibration was performed at the AERONET-EUROPE calibration center, supported by ACTRIS. We also express our gratitude to the developers of the LIRIC algorithm and software. The authors thank Sierra Nevada National Park for support in the maintenance of the Sun-sky photometer station at Cerro Poyos. Maria J. Granados-Muñoz is funded by a Maria Sklodowska-Curie IF under grant agreement no. 796539. Juan Antonio Bravo-Aranda and Antonio Valenzuela received funding from the Marie Sklodowska-Curie Action Cofund 2016 EU project Athenea3i under grant agreement no. 754446. Jose Antonio Benavent-Oltra is funded by the University of Granada through “Plan Propio. Programa 7, Convocatoria 2019”. This work was also supported by the Ambizione program of the Swiss National Science Foundation (project no. PZ00P2 168114).This work evaluates the Lidar-Radiometer Inversion Code (LIRIC) using sun-sky photometers located at different altitudes in the same atmospheric column. Measurements were acquired during an intensive observational period in summer 2012 at Aerosols, Clouds, and Trace gases Research InfraStructure Network (ACTRIS)/Aerosol Robotic Network (AERONET) Granada (GRA; 37.16◦N, 3.61◦W, 680 m above sea level (a.s.l.)) and Cerro Poyos (CP; 37.11◦N, 3.49◦W, 1820 m a.s.l.) sites. Both stations operated AERONET sun-photometry, with an additional lidar system operating at Granada station. The extended database of simultaneous lidar and sun-photometry measurements from this study allowed the statistical analysis of vertically resolved microphysical properties retrieved with LIRIC, with 70% of the analyzed cases corresponding to mineral dust. Consequently, volume concentration values were 46 µm3 /cm3 on average, with a value of ~30 µm3 /cm3 corresponding to the coarse spheroid mode and concentrations below 10 µm3 /cm3 for the fine and coarse spherical modes. According to the microphysical properties’ profiles, aerosol particles reached altitudes up to 6000 m a.s.l., as observed in previous studies over the same region. Results obtained from comparing the LIRIC retrievals from GRA and from CP revealed good agreement between both stations with differences within the expected uncertainties associated with LIRIC (15%). However, larger discrepancies were found for 10% of the cases, mostly due to the incomplete overlap of the lidar signal and/or to the influence of different aerosol layers advected from the local origin located between both stations, which is particularly important in cases of low aerosol loads. Nevertheless, the results presented here demonstrate the robustness and self-consistency of LIRIC and consequently its applicability to large databases such as those derived from ACTRIS-European Aerosol Research Lidar Network (EARLINET) observations.This work was supported by the Spanish Ministry of Economy and Competitiveness through projects CGL2016-81092-R, and CGL2017-83538-C3-1-R; the Excellence network CGL2017-90884-REDT; by the European Union’s Horizon 2020 research and innovation program through ACTRIS project (grant agreement n. 654169)

Living lab for digital literacy and active ageing. Systematic literature review of scientific production in the social sciences

[EN] The aim of this study is to know the state of the art of Living Labs in the field of Social Sciences. To this end, a Systematic Literature Review was carried out with the aim of answering the following research questions: a) what types of studies are carried out on Living Labs, b) what are the aims and objectives of the Living Lab analysed, c) what is its geographical context, d) the type of users it is aimed at and e) what are the characteristics shared by the different Living Labs analysed in the selected literature. After analysing the literature, the results show a predominance of both qualitative research and studies carried out in the European context, as well as heterogeneity in the objectives of the research analysed and coincidence in the characteristics of the Living Labs analysed. The conclusions point to the need to develop research on Living Labs in the field of Social Sciences and, specifically, from an educational perspective that promotes the technological inclusion of the elderly