Project "A Universalidade dos Saberes"

To show with the case of Applied Optics (AO), the adequacy of blended learning to the teaching/learning process in experimental Science and technology (S&T)

Treatment interaction in moments of ambivalence: an exploratory study a case of failure

No processo psicoterapêutico a mudança constrói-se através da emergência e expansão de excepções ao funcionamento problemático do cliente. Contudo, o potencial de mudança destas excepções ou inovações pode ser abortado através da atenuação do seu significado quando o cliente as desvaloriza, trivializa ou nega. Quando este processo se repete ao longo da terapia estamos na presença de ambivalência, na medida em que ocorre uma oscilação recorrente entre duas posições opostas (inovação-retorno ao funcionamento problemático). O presente estudo exploratório tem como principal objectivo descrever a interacção terapêutica nestes momentos de ambivalência, num caso de insucesso psicoterapêutico, recorrendo ao Sistema de Codificação da Colaboração Terapêutica. Os resultados sugerem que a ambivalência emerge maioritariamente no seguimento de intervenções em que a terapeuta desafia a perspectiva habitual da cliente. Os resultados mostram ainda que a terapeuta tende a responder à ambivalência da cliente com um novo desafio, sendo que a cliente tende a expressar novamente ambivalência ou a discordar da terapeuta. Deste modo, quando a terapeuta persiste no desafio verifica-se frequentemente uma escalada no desconforto da cliente, que se manifesta na evolução de uma resposta de ambivalência para uma resposta de invalidação por parte da cliente.Change in psychotherapy occurs through the emergence and expansion of exceptions to the client’s problematic functioning. However, these exceptions’ potential to promote change may be aborted by the attenuation of their meaning, when the client devaluates, trivializes or denies them. When this process repeats itself throughout the therapeutic process, clients are facing ambivalence, since there is a recurrent oscillation between two opposite positions (innovation – return to the problematic functioning). The present exploratory study aims at describing the therapeutic interaction within moments in which ambivalence occurs in an unsuccessful case using the Therapeutic Collaboration Coding System. Results suggest that ambivalence emerges mainly as a response to an intervention in which the therapist challenges clients usual (i.e., problematic) perspective. Moreover, results suggest that the therapist tends to respond to client’s ambivalence with a new challenge intervention which is generally followed by ambivalence or even invalidation from the client. Hence, when the therapist persists in challenging the client there is usually an escalation in clients’ discomfort, expressed in the evolution of a ambivalence response towards an invalidation response.(undefined

Identification of microplastics using Raman spectroscopy: latest developments and future prospects

Widespread microplastic pollution is raising growing concerns as to its detrimental effects upon living organisms. A realistic risk assessment must stand on representative data on the abundance, size distribution and chemical composition of microplastics. Raman microscopy is an indispensable tool for the analysis of very small microplastics (<20 μm). Still, its use is far from widespread, in part due to drawbacks such as long measurement time and proneness to spectral distortion induced by fluorescence. This review discusses each drawback followed by a showcase of interesting and easily available solutions that contribute to faster and better identification of microplastics using Raman spectroscopy. Among discussed topics are: enhanced signal quality with better detectors and spectrum processing; automated particle selection for faster Raman mapping; comprehensive reference libraries for successful spectral matching. A last section introduces non-conventional Raman techniques (non-linear Raman, hyperspectral imaging, standoff Raman) which permit more advanced applications such as real-time Raman detection and imaging of microplastics.publishe

New recycling approaches for thermoset polymeric composite wastes – an experimental study on polyester based concrete materials filled with fibre reinforced plastic recyclates

In this study, a new waste management solution for thermoset glass fibre reinforced polymer (GFRP) based products was assessed. Mechanical recycling approach, with reduction of GFRP waste to powdered and fibrous materials was applied, and the prospective added-value of obtained recyclates was experimentally investigated as raw material for polyester based mortars. Different GFRP waste admixed mortar formulations were analyzed varying the content, between 4% up to 12% in weight, of GFRP powder and fibre mix waste. The effect of incorporation of a silane coupling agent was also assessed. Design of experiments and data treatment was accomplished through implementation of full factorial design and analysis of variance ANOVA. Added value of potential recycling solution was assessed by means of flexural and compressive loading capacity of GFRP waste admixed mortars with regard to unmodified polymer mortars. The key findings of this study showed a viable technological option for improving the quality of polyester based mortars and highlight a potential cost-effective waste management solution for thermoset composite materials in the production of sustainable concrete-polymer based products

An integrated recycling approach for GFRP pultrusion wastes: recycling and reuse assessment into new composite materials using Fuzzy Boolean Nets

In this study, efforts were made in order to put forward an integrated recycling approach for the thermoset based glass fibre reinforced polymer (GPRP) rejects derived from the pultrusion manufacturing industry. Both the recycling process and the development of a new cost-effective end-use application for the recyclates were considered. For this purpose, i) among the several available recycling techniques for thermoset based composite materials, the most suitable one for the envisaged application was selected (mechanical recycling); and ii) an experimental work was carried out in order to assess the added-value of the obtained recyclates as aggregates and reinforcement replacements into concrete-polymer composite materials. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified concrete-polymer composites with regard to unmodified materials. In the mix design process of the new GFRP waste based composite material, the recyclate content and size grade, and the effect of the incorporation of an adhesion promoter were considered as material factors and systematically tested between reasonable ranges. The optimization process of the modified formulations was supported by the Fuzzy Boolean Nets methodology, which allowed finding the best balance between material parameters that maximizes both flexural and compressive strengths of final composite. Comparing to related end-use applications of GFRP wastes in cementitious based concrete materials, the proposed solution overcome some of the problems found, namely the possible incompatibilities arisen from alkalis-silica reaction and the decrease in the mechanical properties due to high water-cement ratio required to achieve the desirable workability. Obtained results were very promising towards a global cost-effective waste management solution for GFRP industrial wastes and end-of-life products that will lead to a more sustainable composite materials industry

Mechanical behaviour analysis of polyester polymer mortars modified with recycled GFRP waste materials

In this study the effect of incorporation of recycled glass-fibre reinforced polymer (GFRP) waste materials, obtained by means of milling processes, on mechanical behaviour of polyester polymer mortars was assessed. For this purpose, different contents of recycled GFRP waste powder and fibres, with distinct size gradings, were incorporated into polyester based mortars as sand aggregates and filler replacements. Flexural and compressive loading capacities were evaluated and found better than unmodified polymer mortars. GFRP modified polyester based mortars also show a less brittle behaviour, with retention of some loading capacity after peak load. Obtained results highlight the high potential of recycled GFRP waste materials as efficient and sustainable reinforcement and admixture for polymer concrete and mortars composites, constituting an emergent waste management solution

Shielding AZ91D-1%Ca from corrosion through ultrasound melt treatment: a study for stent design

Magnesium-based materials show great potential for producing biodegradable stents, but their high corrosion rates are a roadblock. This study investigates whether ultrasound melt treatment can change the corrosion response of an extruded AZ91D-1.0%Ca (wt.%) in Earle's Balanced Salt Solution by tailoring the intermetallics' morphology in the as-extruded state. The results showed that the wires from ultrasound-treated ingots corroded faster than non-treated ones in immersion for up to 6 hours. This trend shifted for longer periods, and ultrasound-treated material showed lower corrosion rates and uniform corrosion, while the non-treated material displayed localized corrosion signs. Tensile testing of the wires demonstrated that immersion in EBSS lowered the tensile strength and elongation at fracture due to material degradation, regardless of the processing route. Nonetheless, this decline was sharper in the non-treated material. These findings suggest that ultrasound melt processing can be a promising method for improving the corrosion resistance of magnesium-based materials, paving the way for their use in manufacturing biodegradable stents.This work was supported by Portuguese FCT under the project UIDB/04436/2020, the doctoral grant PD/BD/140094/2018 and SFRH/BD/145285/2019

On the recyclability of glass fiber reinforced thermoset polymeric composites towards the sustainability of polymers' industry

Considering the added value of recycling solution assessed by an evaluation of flexural and compressive loadingcapacity of PC specimens modified with mechanically recycled GFRP wastes, as well as the inherent environmentaland economic benefits, the incorporation of GFRP recyclates into PC materials has been revealed as a viabletechnological option for the sustainability of the GFRP polymers' industry. Nevertheless, the recyclability of compositematerials is complex and is sometimes seen as a key barrier to the adoption of these materials in some markets.One of the few successful applications, was developed by Reprocover, in Belgium, and it has been commercializedsince 2011. In addition, the recently investigation line that was started and concerning the GFRP recyclates into PCmaterials also called the attention of Global Fiberglass SolutionsTM group. Even so, and although all the efforts thathad been done on developing cost-effective recycling routes, GFRP wastes still remain mired by the scarcenessof reliable outlet markets for the recyclates and clearly developed recycling paths between waste producers andpotential consumers for the recyclates. However, it is foreseen that this scenario will change in the next few yearsas strong investments are being made in this field. The innovation in this field has just started, providing as this waya source of new opportunities