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We present the summary of several years of research about the inhibitor effect of NO2- on the corrosion of reinforcements. We have studied their inhibitor effect using galvanostatic and potentiodynamic polarization curves and we have measured the corrosion rates using the Polarization Resistance method (linear polarization). We have verified by this last technique, Rp, that the NO2- in concrete, if they are used in sufficient proportion, are a complete inhibitor when the Cl are added during the mixing (e.g. mixing whith sea water, CaCl2 as an accelerator in inbitor). Inssufficient amounts of NO2- have never provoked more corrosion in our experiments in concrete. The presence of NO2- always have produced a beneficial effect. The NO2- are also beneficial in carbonated concrete, suppressing or, at least, reducing the attacked area and the corrosion rate of the reinforcements.

We have a system that is unable to keep students excited about their own learning and educational performance. In light of this situation it is the responsibility of educators to make a broad and global reflection on what must be changed and how this change may be managed. We believe that change is possible and there is no objective more necessary for society than investing in its future project. This paper proposes an exhaustive analysis of the current situation of the secondary school teachers and from there on justifies the change through the teaching practice based on innovation and with a better training in pedagogical and didactical issues.

This paper presents a Remote Control System for Small Hydro Energy Power Stations. It is destinated to provide an integral operability of the telecontrolled installation from a remote central position sited into the electric company´s operation offices. It will allow to warrant the strictest security standards that are required nowadays for this type of installations. It has been designed as a storage system of the fundamental information from each power station defined inside the system.

Attempts to model any present or future power grid face a huge challenge because a power grid is a complex system, with feedback and multi-agent behaviors, integrated by generation, distribution, storage and consumption systems, using various control and automation computing systems to manage electricity flows. Our approach to modeling is to build upon an established model of the low voltage electricity network which is tested and proven, by extending it to a generalized energy model. But, in order to address the crucial issues of energy efficiency, additional processes like energy conversion and storage, and further energy carriers, such as gas, heat, etc., besides the traditional electrical one, must be considered. Therefore a more powerful model, provided with enhanced nodes or conversion points, able to deal with multidimensional flows, is being required. This article addresses the issue of modeling a local multi-carrier energy network. This problem can be considered as an extension of modeling a low voltage distribution network located at some urban or rural geographic area. But instead of using an external power flow analysis package to do the power flow calculations, as used in electric networks, in this work we integrate a multiagent algorithm to perform the task, in a concurrent way to the other simulation tasks, and not only for the electric fluid but also for a number of additional energy carriers. As the model is mainly focused in system operation, generation and load models are not developed. The financial support from EPSRC for Liz Varga on project entitled "Transforming Utilities’ Conversion Points" (no. EP/J005649/1) is gratefully acknowledged.

Cooperative learning seems to be the right methodology to tackle the development of the teamwork competence inside the process of teaching?learning at the University. That strategy has been used by lecturers of different faculties and schools of the University of the Basque Country UPV/EHU who have sorted an Educational Team on cooperative learning. The experience was developed in six different groups which add up as 185 students. The outcome of that experience was analysed by means of a questionnaire which gathers the main competences of teamwork. The analysis of the dimensions of the questionnaire shows a structure with two dimensions: (1) 'interpersonal competences' and (2) 'instrumental competences'. Students seem to prioritise the most technical or procedural competences (instrumental) over personal and relationship competences (interpersonal) in their formative process and assessment of their learning.

Thermodynamic cycles requiring high operating temperatures (≥750 °C up to 1200 °C) are currently being explored to improve the sun-to-electricity conversion efficiency of Concentrating Solar Power (CSP) plants. This is calling for the design of new efficient high-temperature (≥750 °C) Thermochemical Energy Storage (TCES) systems, which are fundamental for supplying power on demand during off-sun periods. Recently, Fe-doped CaMnO3 oxides have been proposed as TCES candidate materials, and the determination of their thermodynamics properties via thermogravimetric (TG) analysis allowed evaluation of their heat storage capacity at a very small scale (mg scale). A 10 % Fe-doped CaMnO3 composition (CaMn0.9Fe0.1O3-δ – CMF91) emerged as optimum candidate material for TCES application due to its large heat storage capacity complemented by enhanced thermal stability over multiple oxidation/reduction cycles. To advance in the thermal characterization of these materials at a multigram scale, here we carried out bench-scale reactor tests using CMF91 under conditions considered representative of future CSP plants. The redox-active material has been extruded in the form of porous pellets through a simple production method that required the use of carboxymethylcellulose as a removable binder and water. With the bench-scale reactor tests, the CMF91 pellets showed fully reversible reduction-oxidation in cycles between 500 and 1100 °C under relevant operating pO2 conditions without any deterioration of the pellet's structural integrity. Remarkably, the material exhibited the same δ(T, pO2) profile at this significantly larger scale (~40 g) than the one derived from thermodynamics. Nevertheless, slight differences in oxygen release/uptake profiles between cooling and heating branches can be tracked down to an excess heat generation in the perovskite bed not efficiently extracted by the carrier gas. These results demonstrate that CMF91 oxide is ideally suited for thermal energy storage applications with a large total (thermochemical and sensible) heat storage capacity (~ 916 kJ/kgABO3 or ~ 400 kWh/m3) and good scalability. © 2022 This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska- Curie grant agreement N◦ 74616. Support of the ACES2030-CM from “Comunidad de Madrid” and European Structural Funds to (P2018/EMT-4319), and the Spanish “Ministerio de Economía y Competitividad” through Research Challenges project ARROPAR-CEX (ENE2015-71254-C3-1-R) are also fully acknowledged. M. S´anchez is grateful to Spanish “Ministerio de Economía y Competitividad” by funding through internship FPI (BES-2016-077031). It is greatly acknowledged the Technical Research Support Unit of the Institute of Catalysis and Petroleum Chemistry (ICP-CSIC). The authors fully appreciate the advice provided by Prof. Pedro Avila and Dr. Raquel Portela from the SpeICat group of ICP-CSIC, about the procedure for pellets preparation. Supporting Information Peer reviewed

Abstract The consumption of buildings for the production of heat is expected to decrease in Switzerland in the coming years, in particular following policies encouraging the refurbishment of buildings. This will notably have an impact on the natural gas network, in parallel with the penetration of electric-driven heat pumps. Through a detailed optimization scheme, the evolution of the natural gas (NG) distribution network is studied over a future period of forty years, i.e. up to 2050, on the territory of a large Swiss canton. By way of installing large shares of co-generation units, it is shown that the NG network does not lose its meshed structure, while continuing to play a central role in the production of heat and the generation of part of the additional electricity demand associated with the concomitant penetration of heat pumps. As a novel result, the developed optimization framework allows a detailed, geographically precise view of both the evolution of the NG network, as well as of the optimal location of selected technologies. The adoption of energy networks convergence in urban zones therefore can lead to relevant synergies, avoiding over-investments, increasing system resilience and fostering the use of efficient technologies.