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Research and development of cost-effective, high-performance thermal insulation materials for the construction sector has to be focused on their final application. In particular, solutions for refurbishing historic buildings, which represent 40% of the European building stock, have to offer a good compromise between environmental quality, energy efficiency and conservation aspects. In this paper, the experimental assessment of an insulation material based on aerogel technology, recently developed in the European project EFFESUS, is presented with regard to the material's thermal performance, compatibility with historic fabric and reversibility. The overall results obtained in laboratory testing on a real-size mock-up and in a real-world case application indicate that the new material is a promising solution for retrofitting historic buildings, thanks to its thermal properties, easy application, reversibility and material compatibility.

The repercussions of climate change will be felt in various ways throughout both natural and human systems in Sub-Saharan Africa. Climate change projections for this region point to a warming trend, particularly in the inland subtropics; frequent occurrence of extreme heat events; increasing aridity; and changes in rainfall—with a particularly pronounced decline in southern Africa and an increase in East Africa. The region could also experience as much as one meter of sea-level rise by the end of this century under a 4 °C warming scenario. Sub-Saharan Africa’s already high rates of undernutrition and infectious disease can be expected to increase compared to a scenario without climate change. Particularly vulnerable to these climatic changes are the rainfed agricultural systems on which the livelihoods of a large proportion of the region’s population currently depend. As agricultural livelihoods become more precarious, the rate of rural–urban migration may be expected to grow, adding to the already significant urbanization trend in the region. The movement of people into informal settlements may expose them to a variety of risks different but no less serious than those faced in their place of origin, including outbreaks of infectious disease, flash flooding and food price increases. Impacts across sectors are likely to amplify the overall effect but remain little understood.

In this contribution, we discuss the implementation of a novel microelectromechanical-systems (MEMS)-based energy harvester (EH) concept within the technology platform available at the ISAS Institute (TU Vienna, Austria). The device, already presented by the authors, exploits the piezoelectric effect to convert environmental vibrations energy into electricity, and presents multiple resonant modes in the frequency range of interest (i.e. below 10 kHz). The experimental characterisation of a sputter deposited aluminium nitride piezoelectric thin-film layer is reported, leading to the extraction of material properties parameters. Such values are then incorporated in the finite element method model of the EH, implemented in Ansys Workbench (TM), in order to get reasonable estimates of the converted power levels achievable by the proposed device solution. Multiphysics simulations indicate that extracted power values in the range of several mu W can be addressed by the EH-MEMS concept when subjected to mechanical vibrations up to 10 kHz, operating in closed-loop conditions (i.e. piezoelectric generator connected to a 100 k Omega resistive load). This represents an encouraging result, opening up the floor to exploitations of the proposed EH-MEMS device in the field of wireless sensor networks and zero-power sensing nodes.

This paper presents the results of a thermodynamic and economic evaluation of a novel hybrid combination of a compressed air energy storage and a combined cycle power plant. The new cycle is modeled on basis of a GE LM6000 gas turbine model, an adiabatic compressor model, an air expander and a conventional dual pressure HRSG configuration. Furthermore, a detailed design of the recuperator is presented. With the simulated components, a storage efficiency of 60% is reached. In CHP configuration the total efficiency of the plant reaches up to 86.2%. The thermodynamic and economic performance is compared to a conventional LM6000 combined cycle. For the economic evaluation the German electricity day-ahead prices and average gas price of the year 2014 are used. Overall it is found that the CAES/CCPP concept exhibits far more operation hours per year and a higher profit margin than the compared CCPP. Taking into account the investment and operational costs, especially with steam extraction the net present value of the novel cycle is higher than that of the combined cycle, despite the challenging market environment for storage technologies in Germany.

We report on field effect mobility measurements in methanofullerene [6,6]-phenyl C61C61-butyric acid methyl ester (PCBM) films and in blends of poly(3-hexylthiophene) (P3HT) and PCBM, identical to those used in polymer solar cells. Electron mobilities in the order of 10-3cm2/Vs were found in the pure PCBM films, and electron mobilities of 10-4cm2/Vs were found in P3HT:PCBM blends at room temperature. Mobility measurements on the blends yielded electron mobilities of a factor 10 lower than those in the pure films. Temperature dependent measurements were performed to investigate the temperature dependence of the mobility in both films. In order to understand the discrepancy in the electron mobility between pure film and blend, we investigated the parasitic effects of the contacts on the measured value of mobility, but found that losses in the bulk dominate the current.

p-Type Co(3)O(4) nanostructured films are synthesized by a plasma-assisted process and tested in the photocatalytic production of H(2) from water/ethanol solutions under both near-UV and solar irradiation. It is demonstrated that the introduction of fluorine into p-type Co(3)O(4) results in a remarkable performance improvement with respect to the corresponding undoped oxide, highlighting F-doped Co(3)O(4) films as highly promising systems for hydrogen generation. Notably, the obtained yields were among the best ever reported for similar semiconductor-based photocatalytic processes.

Gas–solid fluidized bed reactors play an important role in many industrial applications. Nevertheless, there is a lack of knowledge of the processes occurring inside the bed, which impedes proper design and upscaling. In this work, numerical approaches in the Eulerian and the Lagrangian framework are compared and applied in order to investigate internal fluidized bed phenomena. The considered system uses steam/air/nitrogen as fluidization gas, entering the three-dimensional geometry through a Tuyere nozzle distributor, and calcium oxide/corundum/calcium carbonate as solid bed material. In the two-fluid model (TFM) and the multifluid model (MFM), both gas and powder are modeled as Eulerian phases. The size distribution of the particles is approximated by one or more granular phases with corresponding mean diameters and a sphericity factor accounting for their nonspherical shape. The solid–solid and fluid–solid interactions are considered by incorporating the kinetic theory of granular flow (KTGF) and a drag model, which is modified by the aforementioned sphericity factor. The dense discrete phase model (DDPM) can be interpreted as a hybrid model, where the interactions are also modeled using the KTGF; however, the particles are clustered to parcels and tracked in a Lagrangian way, resulting in a more accurate and computational affordable resolution of the size distribution. In the computational fluid dynamics–discrete element method (CFD–DEM) approach, particle collisions are calculated using the DEM. Thereby, more detailed interparticulate phenomena (e.g., cohesion) can be assessed. The three approaches (TFM, DDPM, CFD–DEM) are evaluated in terms of grid- and time-independency as well as computational demand. The TFM and CFD–DEM models show qualitative accordance and are therefore applied for further investigations. The MFM (as a variation of the TFM) is applied in order to simulate hydrodynamics and heat transfer to immersed objects in a small-scale experimental test rig because the MFM can handle the required small computational cells. Corundum is used as a nearly monodisperse powder, being more suitable for Eulerian models, and air is used as fluidization gas. Simulation results are compared to experimental data in order to validate the approach. The CFD–DEM model is applied in order to predict mixing behavior and cohesion effects of a polydisperse calcium carbonate powder in a larger scale energy storage reactor.

Maximal L-glutamate/glycine-evoked currents were inhibited by ethanol in Xenopus laevis oocytes expressing recombinant heteromeric NMDA receptors consisting of NR1-NR2A, NR1-NR2B, and NR1-NR2C subunit combinations. Concentration-dependent inhibition was observed at ethanol concentrations of > or = 50 mM both in Ca(2+)-containing and Ca(2+)-deficient, Ba(2+)-containing Mg(2+)-free media. The NR1-NR2C channels were slightly less sensitive to ethanol inhibition than the other heteromeric channels in Ca(2+)-deficient, Ba(2+)-containing medium. The inhibition was unaffected by the clamping-voltage and by a mutation [NR1-NR2A(N595Q)] that prevents the Mg(2+)-blockade of the channels, indicating that the mechanism of action of ethanol differs from that of Mg2+. The results are consistent with the hypothesis that the NMDA receptor subtypes can mediate many behavioural actions of ethanol.