Machining of hybrid composites

Tese de doutoramento. Engenharia Mecânica. Faculdade de Engenharia. Universidade do Porto. 200

Caracterización morfométrica de poblaciones de abejas (Apis mellifera iberiensis) de la region centro de Portugal

La morfometría se utiliza para la discriminación de varias (sub) especies de insectos, en particular en el campo de la Apis mellifera L. En Portugal continental, la A. m. iberiensis es considerada la principal raza autóctona, a pesar de la insuficiencia de estudios morfométricos que 'autentiquen' esta subespecie.info:eu-repo/semantics/publishedVersio

Tool effects on hybrid laminates drilling

Fiber reinforced plastics are increasing their importance as one of the most interesting groups of material on account of their low weight, high strength, and stiffness. To obtain good quality holes, it is important to identify the type of material, ply stacking sequence, and fiber orientation. In this article, the drilling of quasi-isotropic hybrid carbon +glass/epoxy plates is analyzed. Two commercial drills and a special step drill are compared considering the thrust force and delamination extension. Results suggest that the proposed step drill can be a suitable option in laminate drilling

Ultrasonic pulse velocity and physical properties of hybrid composites: A statistical approach

This work describes the correlations between the ultrasonic pulse velocity (UPV) and physical properties of fibrous-particulate hybrid composites made of glass/carbon fabrics and three different micro-inclusions such as silica particles, recycled carbon fibre powder and Portland cement. A full factorial design (214151) is established to identify the effects of volume fraction, stacking sequence and particle type on the physical properties obtained by Archimedes' principle. An electroacoustic transducer (50 kHz) is used to determine the ultrasonic pulse velocity data. Statistical models reveal correlations between UPV and the physical properties of hybrid composites. The combination of UPV and statistical techniques can identify all constitutive phases, being useful to characterise and estimate physical properties in a hybrid system composed of fibres and microparticles.The authors acknowledge the Brazilian Research Agencies, CAPES (MSc scholarship), CNPq (PQ-309885/2019–1) and FAPEMIG (PPM-00075-17) for the financial support provided

Etnografias Urbanas

Olhar as cidades e a vida urbana numa perspectiva etnográfica constitui o desafio deste livro. Compreender as cidades de dentro, de baixo, a partir de urna relação próxima entre quem vê e quem é observado permite ir ao encontro do que de mais incerto e surpreendente as cidades nos têm para oferecer polícias, associações, culturas juvenis, práticas de lazer, territorios psicotrópicos, identidades étnicas, práticas habitacionais... Etnografias Urbanas reúne um conjunto de comunicaóes, comentários e reflexões, de cariz interdisciplinar, realizadas no encontro Cidade e Diversidade: Perspectivas de Desenvolvimento em Antropologia Urbana que, em Setembro de 2001, reuniu cerca de vinte investigadores de várias "gerações" e pertengas disciplinares