LIDA - Artigos em revistas internacionais
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- Aluminum-to-Steel Cladding by Explosive WeldingPublication . Carvalho, Gustavo H. S. F. L.; Galvão, Ivan; Mendes, Ricardo; Leal, Rui M.; Loureiro, AltinoThe production of aluminum-carbon steel and aluminum-stainless steel clads is challenging, and explosive welding is one of the most suitable processes to achieve them. The present work aims to investigate the coupled effect of two strategies for optimizing the production of these clads by explosive welding: the use of a low-density interlayer and the use of a low-density and low-detonation velocity explosive mixture. A broad range of techniques was used to characterize the microstructural and the mechanical properties of the welds, specifically, optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, electron backscatter diffraction, microhardness and tensile-shear testing with digital image correlation analysis. Although aluminum-carbon steel and aluminum-stainless steel have different weldabilities, clads with sound microstructure and good mechanical behavior were achieved for both combinations. These results were associated with the low values of collision point and impact velocities provided by the tested explosive mixture, which made the weldability difference between these combinations less significant. The successful testing of this explosive mixture indicates that it is suitable to be used for welding very thin flyers and/or dissimilar materials that easily form intermetallic phases.
- Explosive welding of aluminium to stainless steel using carbon steel and niobium interlayersPublication . Carvalho, G.H.S.F.L.; Galvão, I.; Mendes, R.; Leal, R. M.; Loureiro, A.This work aimed to study aluminium to stainless steel explosive welds produced using two different interlayers: carbon steel and niobium. The use of each interlayer was analysed and compared microstructurally and mechanically using many characterisation techniques. The final joints using both interlayers presented favourable interfacial microstructure: waves on both interfaces. However, the joint using the carbon steel interlayer showed the best mechanical properties compared to the joints using the niobium interlayer. All interfaces found on both welds were wavy. However, depending on the metallic alloy combination, the shape of the wave is completely different. The results suggest that the shape of the waves is influenced by the shock impedance mismatch of the materials being welded. The impedance mismatch parameter (IMP) developed for explosive welding in this work proved to be a compelling method to order metallic combinations in a single axis to estimate the tendency to form typical or curled waves. Typical symmetrical waves tend to develop less quantity of IMCs than curled waves. However, the mechanical tests performed did not detect differences that could have been caused by this difference.
- River(s) Wear: Water in the Expanded FieldPublication . Santos, Miguel; Wainwright, JohnThis article elaborates on an artist-in-residence project funded by the Leverhulme Trust in the Geography Department at Durham University in 2015–16. The project confronted artistic and scientific perspectives to investigate how people in the North-East of England perceive and value their river environments and to recognize potential contributions to catchment management. The project identified a variety of disconnexions and hierarchies in the River Wear catchment and formulated artistic interventions for nonhuman audiences. This article reflects on water holistically and explores transdisciplinary views to propose water in its expanded field. Water in the Expanded Field is plural, complex, and aims at decentering the human importance. It promotes water multiple perspectives, including the more-than-human world and acknowledging water’s ontological importance, developed by the speculative artistic practice of producing works of art for nonhuman audiences and then transposed to water debates. The article converges distinct evidence pointing to the importance of composting existing knowledge and dualistic reasoning to promote pluriversal ontologies of water.
- Virtual Reality in Depressive and Anxiety Symptomatology – Contributions to REVIDA project from a mobile app mappingPublication . Ruívo, Marília; Frontini, Roberta; Pernencar, CláudiaThe worldwide prevalence of mental health diseases is alarming. 792 million individuals have a mental disorder such as anxiety or depression. Treatment varies among the types of illness. They can be expensive and, in order to be effective, must address a combination of psychotherapy and medications. The drugs used for treating symptoms present a risk of negative side effects. Studies have shown the benefits of other co-therapies such as physical exercise. In this case, the ability to simulate reality can strongly increase the introduction of other psychological therapies and treatment results can be improved through new immersive experiences. Virtual Reality Exposure Therapy has demonstrated its effectiveness by allowing patients to gradually face fearful stimuli or stressful situations. Recent studies showed that the use of Virtual Reality is effective and safe for mental health. Particularly, in the scenario of how Virtual Reality simulation could increase empathy and behaviour change. This article presents a preliminary study of the REVIDA project: It aims to investigate through Benchmarking and SWOT Analysis the possible integration of Virtual Reality in mental illness monitoring in Portugal. Results show that there exist several new opportunities for using Virtual Reality technology in mental health and wellbeing.
- Drawing powersPublication . Poeiras, Fernando
- The red seaweed Giant Gelidium (Gelidium corneum) for new bio-based materials in a circular economy frameworkPublication . Mouga, Teresa; Fernandes, Isabel BarretoGelidium corneum (Giant Gelidium or Atlantic agar) is a well-known red seaweed harvested for its high-quality agar content. Agar is a mixture of the polysaccharides used in the food industry as a gelling, thickener, clarifying, and stabilizer agent. The best agar quality is also used in the laboratory as bacteriological agar. Yet, in recent years, the species has been studied for many other applications. Examples of uses are pharmaceuticals, cosmetics, food supplements, bioremediation, biofuels, biofertilizers and biostimulants, biomaterials, and nanocrystals, among others. The use of this biomass, though, raises concerns about the sustainability of the resource, since this is not a cultivated species, being harvested in the wild. Thus, other uses of G. corneum biomass increase pressure on wild stocks already stressed due to climate change. However, in a biorefinery approach, a new trend is emerging, using waste biomass rather than harvested biomass to produce new bio-based materials. These are smart solutions that transform waste into innovative products, useful for various sectors of society while reducing the impact of biomass exploitation. The aim of this review paper, thus, is to address the current state of G. corneum biology, ecology, threats, its current uses and market, and the ongoing research on innovative proposals in a circular economy framework.
- Are you ready for the challenge? Social Media Health Challenges for Behaviour ChangePublication . Saboia, Inga; Almeida, Ana Margarida Pisco; Sousa, Pedro; Pernencar, CláudiaChallenges are one of the most common strategies used by Opinion Leaders on Social Media to engage users. They are often found in different areas; in the Health field, the use of challenges is growing, namely through initiatives aiming at eating behaviour change. Instagram is considered to be one of the most used Social Media applications to develop these initiatives, allowing Opinion Leaders to communicate and engage with their online followers. Despite this scenario, little is known regarding how Health Challenges are being used and what is their impact on behaviour change. Previous research has already shown how Opinion Leaders use Instagram to promote eating behaviour change. The purpose of this paper is to conceptualize, describe and discuss Social Media Health Challenges, aiming to analyse Instagram challenges on healthy eating. The study was organized in two phases: the first one is a literature review based on Prisma method that supported the conceptualisation of SocialMedia Challenges and the design for the second phase where Social Media Health Challenges of Opinion Leaders, such as Nutritionists, Health Lifestylers and Patient Opinion Leaders (POLS) were analysed. Results showed that most of the challenges are promoted by Patient Opinion Leaders and Health Lifestylers. Followers adhere to Social Media Health Challenges related to weight loss, engaging with Opinion Leaders. The psychological-cognitive components (such as habits, motivation, and self-control) were found in the analysed challenges, and Instagram is one of the used tools to promote these Initiatives. These results point to new paths regarding future research on other behaviour change online initiatives.