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A produção de biodiesel tem como subproduto o glicerol bruto que tem grau de pureza da ordem de 80%-88% em glicerol e é produzido num rácio de 1:10 (em massa) em relação à produção de biodiesel. No presente estudo pretendeu-se avaliar a possibilidade do uso deste subproduto em estado de pureza intermédio como aditivo para materiais cimentícios. É apresentado um estudo experimental sistemático relativo a propriedades mecânicas e físicas de pastas de cimento e argamassas, e apontados os principais benefícios que podem ser obtidos com o recurso a este sub-produto. O programa experimental permitiu observar comportamentos semelhantes aos que se obtêm com recurso a aceleradores de presa / anticongelantes comerciais. Fundação para a Ciência e a Tecnologia (FCT)

Nowadays, many construction companies use maturity-based approaches to support decisions that have strong impact on costs and sustainability of the construction process, such as: age of pre-stressing operations, decision of propping/formwork removal; instant of subjection to load, etc. Current approaches to quality control through maturity consist in evaluating the compressive strength evolution of the concrete mix at a reference curing temperature (usually 20°C), together with the determination of the apparent activation energy (Ea) of the mix. The value of Ea is usually obtained from one of these three sources: (i) reference recommendations based on the type of cement; (ii) calorimetric testing; (iii) testing of compressive strength evolution at several distinct temperatures. The only technique of determining Ea that really addresses a mechanical property is the latter one, demanding however the deployment of many specimens and tests. Furthermore, the destructive character of this technique limits the possibility of maintaining the same specimen for the entire Ea testing, thus increasing the variability/scattering of results. The present study intended to evaluate the possibility of assessing mechanical-based activation energy for concrete through continuous or quasicontinuous assessments of E-modulus since very early ages. E-modulus is a mechanical property depending on the advancement of the hydration reaction and the temperature stories during the curing, with the interesting characteristic of allowing non-destructive testing to be carried out. This paper presents an inter-laboratory and inter-technique comparative study of E-modulus evolution at several temperatures. Three laboratories were involved, contributing with specific testing techniques applied to a single mix of normal strength concrete: 1) BTJASPE (BéTon au Jeune Age, Suivi de la Prise et du module d'Elasticité), available at IFSTTAR in France; 2) EMM-ARM (Elasticity Modulus Measurement through Ambient Response Method) available at the University of Minho in Portugal; 3) TSTM (Temperature Stress Testing Machine), available at Université Libre de Bruxelles in Belgium. Fundação para a Ciência e a Tecnologia (FCT)

Sustainability assessment and rating systems are intended to foster more sustainable design, construction, operation, maintenance and disassembly/deconstruction promoting and making possible a better integration of environment, societal, and cost concerns with other traditional decision criteria. The use of improved and building technologies can contribute considerably to better environmental cycle and then to the sustainability of the constructions. It is widely recognised in the of Building Sustainability Assessment that Life Cycle Assessment (LCA) is a much preferable method for evaluating the environmental pressure caused by materials, Building assemblies and the whole life-cycle of a building. Nevertheless, LCA tools are not extensively used in building design and most of building sustainability assessment and systems are not comprehensive or consistently LCA-based. Reasons for this failure above all related to the huge variety and amount of material flows and processes of building’s Lifecycle and to the complexity of the stages of a LCA. This paper will present the difficulties and possible solutions to integrate more accurate environmental methods in rating systems. In this context, the paper will also present the work that is being carried out in the development of the Portuguese Building Sustainability Assessment system (SBTool PT)

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.

Asphalt rubber (AR) mixtures constitute an alternative to traditional hot mix asphalts (HMA), especially when considering the following characteristics: higher fatigue and higher reflective cracking resistance; noise reduction and higher friction, in these later when suitable aggregate gradations are used. However, besides these apparently sound results, a holistic approach to the associated sustainability issues should be made, considering the pavement life cycle. The work undertaken included the comparison of the AR and HMA, regarding the following parameters: (i) structural performance; (ii) life cycle analysis; (iii) environmental evaluation of greenhouse gases emissions. The results allow concluding that AR mixtures present advantages in terms of performance and emissions, although the costs of those mixtures are higher than conventional mixtures. Nevertheless, more research is needed to evaluate the life cycle performance, including the reduction of the production temperature in order to obtain more economically and environmentally sustainable mixtures. (undefined)

Abstract Antimony telluride (Sb 2 Te 3 ) is a chalcogenide material used in thermoelectric applications. The deposition of thin films of Sb 2 Te 3 requires a precisely controlled process to achieve a desirable high thermoelectric figure-of-merit. The optimization of the thermal co-evaporation process for p-type Sb 2 Te 3 thin-film onto plastic substrates (Kapton© polyimide) for thermoelectric applications is reported. The influence of deposition parameters and composition on thermoelectric properties was studied, seeking optimal thermoelectric performance. Energy-dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy all confirmed the formation of Sb 2 Te 3 thin films. Seebeck coefficient (up to 190 μVK −1 ), in-plane electrical resistivity (8–15 μΩm), carrier concentration (1 × 10 19 –7 × 10 19 cm −3 ) and Hall mobility (120–180 cm 2 V −1 s −1 ) were measured at room temperature for the best Sb 2 Te 3 thin-films.

Uma aldeia, perdida num concelho, pode ser rapidamente esquecida pelo tempo quando a sua população é reduzida e os picos de emigração contribuem ainda mais para que esta tenha uma tendência a desertificar e a deixar perdida no tempo a sua identidade. Agra é uma aldeia tipicamente minhota, tendo sido considerada “Aldeia de Portugal” em 2005. Anteriormente tinham sido realizadas as primeiras intervenções para recuperação do património existente, também como forma de fixar a população. Este trabalho de investigação pretende compreender de que forma o turismo pode contribuir para a sustentabilidade local e do património cultural de Agra. Através de um trabalho de pesquisa bibliográfica e, sobretudo, de observações no terreno, pretendeu-se demonstrar o impacto que a aposta do turismo teve na aldeia e perceber até que ponto este pode ser um motor de desenvolvimento local e funcionar em prol de uma população que vive isolada. Os fundos comunitários foram, sem dúvida, uma alavanca fundamental neste sentido. A questão que se coloca é se, depois dos investimentos feitos, a população tem mantido a dinâmica necessária para que o turismo continue a contribuir para a sustentabilidade local e do património cultural de Agra, não deixando esmorecer todo o trabalho feito até ao presente, em termos de recuperação e preservação. A village, lost in a municipality, may be quickly forgotten by time when its population is reduced and the peaks of emigration further contribute to its tendency to desertification and to lose its identity. Agra is a typical Minho village and was considered "Village of Portugal" in 2005. Previously, the first interventions to recover the existing heritage were carried out, also as a way of keeping people in the village. This research aims to understand how tourism can contribute to the local and cultural heritage sustainability in Agra. Through bibliographical research and, mainly, field observations, we sought to infer the impact that tourism had in the village and understand to what extent this can be an engine of local development and operate in favor of a population that lives isolated. EU funds were undoubtedly a key lever in this direction. The question that arises is whether, after the investments, the population has maintained the dynamics needed to ensure that tourism continues to contribute to the local and cultural heritage sustainability in Agra, without letting wilt all the recovery and preservation work achieved to date. Dissertação de mestrado em Património e Turismo Cultural

The energy efficiency of buildings is nowadays one of the main concerns of the construction market. But, Indoor Environmental Quality of Buildings (IEQ) should not be disregarded. To achieve an adequate quality of buildings it is necessary to consider a set of aspects that are interconnected and influence each other, not always in a favourable way. The selection of the most suitable construction solution and materials for the building elements must consider its contribution for the IEQ (thermal and acoustic comfort, daylight conditions and the indoor air quality) inside the buildings, its energy efficiency and its environmental impact (considering the embodied energy, for example), but also the weight of the solution and its effect on the structural project of the building. The solutions adopted in buildings, usually, only optimize no more than one of the necessary comfort requirements. In many cases, the best solutions to accomplish different comfort requirements are not compatible, especially in what concerns natural ventilation and lighting strategies and the acoustic and thermal performance. So, it is necessary to have an integrated approach to ensure the best overall behaviour taking into account all of the, sometimes incompatible, comfort and energy efficiency requirements. In this work the use of a multi-criteria analysis, to balance all these aspects on the design phase, in order to assist the designer in the selection of construction solutions and materials will be presented. The selection of the most adequate construction solutions will increase the buildings IEQ, energy performance and also its environmental impact.