113 documents found, page 1 of 12
Low-cost portable sensor for uplastics differentiation
Penso, C. M.; Paiva, M. C.; Viana-Gomes, J.; Rocha, J.L.; Gonçalves, L. M.Na última década, os μplásticos tornaram-se um dos principais problemas de poluição nos oceanos, cursos de água e rios, atraindo atenção devido aos efeitos nocivos que provocam no meio ambiente e na saúde. Os métodos atuais para quantificação de μplásticos incluem imagiologia hiperespectral, espectroscopia de Raman e espectroscopia de infravermelho por transformadade Fourier (FTIR). No entanto, estes equipament...
3D‐printed cryomilled poly(ε‐caprolactone)/graphene composite scaffolds for bon...
Dias, Daniela; Vale, A. Catarina; Cunha, Eunice Paula Freitas; Paiva, M. C.; Reis, R. L.; Vaquette, Cedryck; Alves, N. M.In this study, composite scaffolds based on poly(caprolactone) (PCL) and non-covalently functionalized few-layer graphene (FLG) were manufactured by an extrusion-based system for the first time. For that, functionalized FLG powder was obtained through the evaporation of a functionalized FLG aqueous suspension prepared from a graphite precursor. Cryomilling was shown to be an efficient mixing method, producing a...
Polylactic acid/carbon nanoparticle composite filaments for sensing
Silva, Mariana M.; Lopes, Paulo Estevão Caldeira; Li, Yilong; Pötschke, Petra; Ferreira, Fernando; Paiva, M. C.Polylactic acid (PLA) is a bio-based, biodegradable polymer that presents high potential for biomedical and sensing applications. Ongoing works reported in the literature concern mainly applications based on 3D printing, while textile applications are hindered by the limited flexibility of PLA and its composite filaments. In the present work, PLA/multiwall carbon nanotube (MWCNT) composite filaments were produc...
Potential of Graphene–Polymer composites for ligament and tendon repair: a review
Peixoto, Tânia; Paiva, M. C.; Marques, António T.; Lopes, Maria A.Tendon/ligament injuries are debilitating conditions that affect the life quality of a great percentage of the adult population. Several challenges still have to be addressed regarding the repair of these tissues, as current treatments show limited success. The use of biocompatible and biodegradable polymeric scaffolds potentially helps accomplish a complete and long-term functional repair but, unfortunately, t...
Electrospun nanocomposites containing cellulose and Its derivatives modified wi...
Teixeira, Marta A.; Paiva, M. C.; Amorim, M. T. Pessoa de; Felgueiras, Helena PradoWound healing requires careful, directed, and effective therapies to prevent infections and accelerate tissue regeneration. In light of these demands, active biomolecules with antibacterial properties and/or healing capacities have been functionalized onto nanostructured polymeric dressings and their synergistic effect examined. In this work, various antibiotics, nanoparticles, and natural extract-derived produ...
Bio-inspired deposition of electrochemically exfoliated graphene layers for ele...
Utech, Toni; Pötschke, Petra; Simon, Frank; Janke, Andreas; Kettner, Hannes; Paiva, M. C.; Zimmerer, CordeliaElectrochemically exfoliated graphene (eeG)layers possess a variety of potential applications, e.g. as susceptor material for contactless induction heating in dynamic electro-magnetic fields, and as flexible and transparent electrode or resistivity heating elements. Spray coating of eeG dispersions was investigated in detail as a simple and fast method to deposit both, thin conducting layers and ring structures...
Health and safety concerns related to CNT and graphene products, and related co...
Sousa, Susana P.B.; Peixoto, Tânia; Santos, Raquel M.; Lopes, Ascensão; Paiva, M. C.; Marques, António T.The use of Carbon Nanotubes (CNT) and Graphene increased in the last decade and it is likely to keep increasing in the near future. The attractiveness of their properties, particularly the possibility to enhance the composites performance using a tailor made methodology, brings new materials, processes and products for highly demanding industrial applications and to the market. However, there are quite a lot of...
Biodegradable polymer nanocomposites for ligament/tendon tissue engineering
Silva, M.; Ferreira, F. N.; Alves, N. M.; Paiva, M. C.Ligaments and tendons are fibrous tissues with poor vascularity and limited regeneration capacity. Currently, a ligament/tendon injury often require a surgical procedure using auto- or allografts that present some limitations. These inadequacies combined with the significant economic and health impact have prompted the development of tissue engineering approaches. Several natural and synthetic biodegradable pol...
Mixed carbon nanomaterial/epoxy resin for electrically conductive adhesives
Lopes, Paulo Estevão Caldeira; Moura, Duarte; Hilliou, L.; Krause, Beate; Pötschke, Petra; Figueiredo, Hugo; Alves, Ricardo; Lepleux, EmmanuelThe increasing complexity of printed circuit boards (PCBs) due to miniaturization, increased the density of electronic components, and demanding thermal management during the assembly triggered the research of innovative solder pastes and electrically conductive adhesives (ECAs). Current commercial ECAs are typically based on epoxy matrices with a high load (>60%) of silver particles, generally in the form of m...
Modelo de apoio à tomada de decisão para a seleção de projetos, tendo como crit...
Paiva, M. C.Impulsionadas por uma crescente condição competitiva, grande número de empresas esta mudando a forma de medir seu desempenho. Os indicadores das empresas não devem ficar restritos aos índices financeiros,mas sim assumirem a necessidade de um constante alinhamento e integração entre os indicadores financeiros e não financeiros, fazendo com que ocorra também integração entre todos os departamentos. O uso do siste...