Cathode ray tube glass waste was used to produce glass foams by a powder sintering route. The glass waste powder was mixed with small amounts (5 and 8 wt%) of coal fly ash, which acted as foaming agent, and the compacts of the mixed powders were heated at different sintering temperatures in the range 600–800 °C for various dwell times (30–120 min). The effect of the different processing conditions on the microstructural characteristics (porosity, pore size and pore size distribution), mechanical resistance and thermal conductivity of the produced foams was investigated. The volume of pores tended to increase with sintering temperature and time, and glass foams (with a porosity higher than 50 %) were only achieved after sintering at 750 °C. The average pore size increased with sintering temperature and dwell time, and pore growth was particularly accentuated at 800 °C, where coalescence of the pores occurred, with a consequent decrease in compressive strength. Selected combinations of the sintering temperature, dwell time and foaming agent led to glass foams with a satisfactory microstructural homogeneity, which exhibited mechanical strength and thermal conductivity values similar to commercial foams used as thermal insulating materials. © 2016, Springer Science+Business Media New York.

Abstract With the aim of characterising a commercially available epoxy adhesive used for fibre-reinforced polymers strengthening applications, when submitted to different environmental conditions, mainly thermal (TC), freeze–thaw (FT), and wet–dry (WD) cycles and immersion in pure (PW) and water with chlorides (CW) for periods of exposure that lasted up to 16 months, an experimental program was carried out. Several methodologies were used in its characterization, mainly the scanning electron microscope (SEM), dynamic mechanical analysis (DMA), standard tensile tests (STT) coupled with digital image correlation (DIC). In general the results revealed that the chemical composition was not affected by the environmental conditions. Nevertheless, it was verified through \{DMA\} and \{STT\} that the modulus of elasticity and tensile strength of the epoxy adhesive increased in the TC, while the specimens submitted to \{PW\} and \{CW\} faced a high degradation in terms of its mechanical properties. Eventually, the glass transition temperature (Tg) was not affected by the environmental conditions, apart from the specimens subjected to \{TC\} and FT, presenting a higher and lower Tg, respectively, when compared with the reference specimens.

Nowadays some possible alternative methods to replace the batteries as power source, or to achieve better maintenance of existing (or smaller) batteries, are the so called Energy Harvesting (EH) methods, i.e. to obtain energy from the environment or recover and store energy generated by the human body in its usual activities. However, this requires specific technology and materials and usually a multidisciplinary team. For this reason, inclusion a topic on energy harvesting in educational programs of several engineering specialties at technical universities is of great importance.In this paper we present some results from interdisciplinary collaboration at Faculty of Science and Technology at Nova University of Lisbon on the energy harvesting. Experiments were performed in order to calculate the power that could be generated from the chest movements during breathing and from the feet during walking, etc. For the experiments, mostly piezoelectric effect was explored.

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