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AbstractThe protic ionic liquid (PIL) N‐butylimidazolium trifluoromethanesulfonate ([BIm][TfO]) was obtained for the first time and incorporated into a sol–gel‐derived di‐ureasil matrix with a concentration of X=5, 10, and 30 %, where X is the ratio of the mass of PIL per mass of poly(oxyethylene). Four years after their synthesis, the resulting quasi‐anhydrous electrolytes remained amorphous, homogeneous, flexible, and thermally stable below 200 °C. SEM/EDS data revealed the presence of the PIL at the surface of the xerogels with X>5 %, demonstrating that this type of morphological characterization is mandatory to avoid misleading ionic conductivity values. The highest ionic conductivity was produced in the washed sample with X=30 % (3.5×10−5 and 2.1×10−3 S cm−1 at 25 and 170 °C, respectively). The present family of electrolytes yielded higher conductivities than the N‐ethylimidazolium trifluoromethanesulfonate‐based analogues introduced earlier by our group and may thus be considered as promising candidates for applications in fuel cells.

Fungi, particularly aquatic hyphomycetes, have been recognized as playing a dominant role in microbial decomposition of plant litter in streams. In this study, we used a microcosm experiment with different levels of fungal diversity (species number and identity) using monocultures and combinations with up to five aquatic hyphomycete species (Articulospora tetracladia, Tricladium splendens, Heliscus submersus, Tetrachaetum elegans and Flagellospora curta) to assess the effects of ethanol and phenanthrene on three functional measures: plant litter decomposition, fungal biomass accrual and reproduction. Alder leaves were conditioned by fungi for 7days and then were exposed to phenanthrene (1mgL(-1)) dissolved in ethanol (0.1% final concentration) or ethanol (at the concentration used to solubilise phenanthrene) for further 24days. Exposure to ethanol alone or in combination with phenanthrene decreased leaf decomposition and fungal reproduction, but increased fungal biomass produced. All aspects of fungal activity varied with species number. Fungal activity in polycultures was generally higher than that expected from the sum of the weighted performances of participating species in monoculture, suggesting complementarity between species. However, the activity of fungi in polycultures did not exceed the activity of the most productive species either in the absence or presence of ethanol alone or with phenanthrene.

Intensification, concentration and specialization of dairy cow farms originate many activity by-products, such as wastewater and slurry which implies treatment costs, reduce environmental quality and promote social conflicts between the urban and rural population. These (by)products present a high potential for energy recovery from biogas produced in anaerobic digestion processes, thus contributing to sustainable development. This study is focused on the development of a GIS-based spatial support decision system that supports Multicriteria Analysis and Weighted Hierarchical Analysis (AHP) models aiming to identify site locations with appropriate conditions for the implementation of biogas production units, using waste and wastewater produced by the dairy cow farms in Barcelos municipality (NW Portugal). This spatially explicit model considers environmental, social and economic factors, as well as, legal location constraints tested with a consistent sensitivity analysis of the modelling processes and results. The results indicate sites with appropriate conditions for the location of biogas production units, considering the minimal distance to the dairy cow farms, electric and road networks, in higher areas with forest land cover and maximizing the distance from the urban spaces, as well as, from the river/ground water surfaces and agricultural/ecological reserves. In the next studies it´s relevant to explore biogas units dimensioning concerns, explore other complementary biomass sources in anaerobic (co)digestion solutions and expand collected spatial data to spatial decision support system during future biogas units operation phase.

Reliability is extremely important for control systems of energy distribution and generation. The IEC 61850 standard specifies an open architecture and communication protocols for such applications. The standard defines an open control architecture for networked control systems composed by intelligent electronic devices, stating some requirements that must be accomplished when developing reliable controllers for such systems. In this paper, we present a systematic and formal methodology to be adopted to achieve the correct implementation of the communication requirements of this standard. The methodology consists in five steps: modeling of real-time communication requirements defined by the standard; simulation of the obtained model; formal verification of the model, improved in the previous step; translation of the global model (simulated and verified) into the input language of the real controller; and finally, application of conformance testing technique to the computational routine implemented in the real controller. Presented research deals with the proposition of a strategy to synthesize and validate models of systems developed under IEC61850 real-time requirements (GOOSE and SMV) through simple operational conditions cases that, once validated, can be used in performance and conformance testing of more complex systems. The proposed methodology allows designers to synthesize reliable systems under IEC61850 real-time communication requirements.

Invasive alien species (IAS) can disrupt important ecological functions in aquatic ecosystems; however, many of these effects are not quantified and remain speculative. In this study, we assessed the effects of the invasive crayfish Procambarus clarkii (Girard, 1852) on leaf litter decomposition (a key ecosystem process) and associated invertebrates using laboratory and field manipulative experiments. The crayfish had significant impacts on leaf decomposition due to direct consumption of leaf litter and production of fine particulate organic matter, and indirectly due to consumption of invertebrate shredders. The invertebrate community did not appear to recognize P. clarkii as a predator, at least in the first stages after its introduction in the system; but this situation might change with time. Overall, results suggested that the omnivore invader P. clarkii has the potential to affect detritus-based food webs through consumption of basal resources (leaf litter) and/or consumers. Recognizing that this IAS is widespread in Europe, Asia and Africa, and may attain high density and biomass in aquatic ecosystems, our results are important to develop strategies for improving stream ecosystem functioning and to support management actions aiming to control the invasive omnivore P. clarkii.

Abstract The reduction of the energy consumption and carbon emissions in the building sector is an important target for actions to mitigate the climate changes and different actions are being carried out to promote a transition to a low carbon built environment. However, present standards are mainly focused on new buildings which may result counter-productive in existing ones, due to their technical, functional and economic constraints. One of the most common problems in the current way of assessing building renovation scenarios is that only energy savings and cost are considered, disregarding additional benefits. Many studies, based on real cases, have already highlighted the relevance of these so-called co-benefits, which can be felt at the building level (and therefore they should be considered in the definition of the renovation measures) and also at the level of society. The present investigation has been developed under the scope of IEA EBC Annex 56 project, and a method to integrate co-benefits in the evaluation of the renovation scenarios towards both the nearly-zero emissions and the nearly-zero energy objectives is proposed. It has been applied to case-studies from several European countries and based on subsequent findings recommendations for policy makers and professional owners are presented.

Abstract Public school buildings represent an important share of public buildings in Europe, some of them built several decades ago. In Portugal, there are about 5800 public schools, many of them in free-running conditions, with significant thermal discomfort and without any heating strategy due to economic restrictions. This work studies the Portuguese Brandao school model (from the ‘70 s), which comprises about 100 non-refurbished basic schools. This paper suggests the passive refurbishment of these public schools with some affordable interventions, regarding the climate features and the reduced capacity to support the operating costs. A prototype classroom was prepared in a Brandao school, in Porto. The in situ experimental campaign consisted of temperature, relative humidity, CO2 concentration and energy consumption measurements. The prototype construction included the improvement of the envelope and of the technical systems. The main goals of this work are: (1) the comparison of the prototype in-service thermal performance in pre-existing conditions and the improvement after the refurbishment in free-running conditions or with some intermittent heating strategies; (2) the establishment of discomfort indexes for the assessment of the discomfort for Mediterranean temperate climate; (3) the quantification of the energy consumption vs discomfort regarding the passive refurbishment strategy and the intermittent heating strategies. When comparing the before and after refurbishment results, the mean daily discomfort indicator has decreased from 34.7 °C.hour to 25.2 °C.hour in free-running conditions and after the refurbishment has decreased from 25.2 °C.hour to 11.9 °C.hour for 3 heating hours strategy and to 2.5 °C.hour for 10 heating hours strategy. There was an expected increase of CO2 inside the classroom for the corresponding months before and after refurbishment, although the mean CO2 was below the required 1500 ppm.

Rethink the interventions, human practices and their effects on the natural environment, for the preservation of life and biodiversity, threatened by the capitalist model of production, consumption and disposal, becomes each day more indispensable and then the understanding of the environmental crisis is gaining space in all segments of society. This understanding is increasingly founded on theoretical and epistemological assumptions, so that considering the role of universities as knowledge building space and other duties and responsibilities towards society, this authors papers understand fundamental the insertion of the environmental approach (greening) in its various fronts (education, research, extension and management). Following the line of several researches about the subject, as well as from research groups in Brazil and in Portugal to which authors are affiliated, this paper aims to identify how the issue of sustainability is taught in the various UMinho engineering programs. This study is part of a broader research, and thus it is limited to teaching, within the engineering scope of this university. It is, therefore, a case study, carried out by a documental research that aims to identify at the UMinho engineering programs that incorporate sustainability concepts into their curricula and, within these programs, identify the courses that possibly work aspects of sustainability and how they work these, particularly, if they use PBL to do this. Also, it is intended to find out about other activities that work the theme and that somehow subsidize the education for a more complete approach to sustainability through research and extension. The study, thus, provides an overview of the greening of engineering courses UMinho, and highlights those working the theme according to a systemic approach, problematizing, practical and integrative that already it was found in several studies be the most suitable to make professionals focused on sustainability. FCT -Fundação para a Ciência e a Tecnologia(UID/CEC/00319/2013) info:eu-repo/semantics/publishedVersion