Among the unique characteristics associated to gold nanoparticles (AuNPs) in biomedicine, their ability to convert light energy into heat opens ventures for improved cancer therapeutic options, such as photothermal therapy (PTT). PTT relies on the local hyperthermia of tumor cells upon irradiation with light beams, and the association of AuNPs with radiation within the near infrared (NIR) range constitutes an a...
Despite the undoubtable interest in energy conversion, thermoelectric (TE) materials can be approached from a temperature-sensitive perspective, as they can detect small thermal stimuli, such as a human touch or contact with cold/hot objects. This feature offers possibilities for different applications one of them being the integration with scalable and cost-effective, biocompatible, flexible, and lightweight t...
Performance of traditional railway structure depends significantly on the behaviour of its support layers, particularly the ballast. This layer’s rock particles are selected to ensure high mechanical strength, but traffic and mechanical maintenance break and wear the particles. Consequently, the layer incurs permanent deformations that degrade its strength and increase deformability and permeability. Particle p...
Although the great advances in medicine, there are still many limitations related to materials that can interact with the human body and its cells. One of the major challenges is developing biocompatible materials that can be used to skin repair treatments, tissue regeneration, inflammation, and wound treatments, among other problems. The most critical step to explore new materials development still remains in ...
Ballast aggregate is a natural material widely used in railway lines. Its mechanical properties and particle geometry are meticulously defined using well-established standards and characterisation procedures. Though extensively validated, these procedures have some limitations: they are operator dependent; only provide major particle dimensions; do not inform on surface colour; nor allow for advanced particle w...
Abstract: In this study, titanium dioxide (TiO2) nanostructured films were synthesized under microwave irradiation through low temperature synthesis (80 °C) and integrated in ultraviolet (UV) photodetectors and as photocatalysts. Bacterial nanocellulose (BNC), tracing paper, and polyester film were tested as substrates, since they are inexpensive, flexible, recyclable, lightweight, and when associated to low te...
The sol-gel method was employed in the preparation of a novel range of organicinorganic biohybrid electrolytes composed of a di-urethane cross-linked poly(ε- caprolactone) (PCL(530) chains/siloxane doped with different amounts of sodium triflate (NaCF3SO3.xH2O). The samples are semi-crystalline and thermally stable up to ca. 250 ºC. The maximum ionic conductivity (4.1 × 10-7 , 1.5 × 10-4 and 8.8 × 10-4 S cm-1 a...
As descontinuidades marcam de forma decisiva a deformabilidade e a resistência, mas também a condutividade hidráulica e a transmissão de vibrações em maciços rochosos. Se a medição de certas características do material rochoso é uma tarefa corrente, já a caracterização da topografia das superfícies é difícil de medir e quantificar de forma inequívoca. Trabalhos anteriores empregam métodos de digitalização com e...
A qualidade geométrica das vias-férreas é um parâmetro fundamental no âmbito da avaliação do desempenho destas infraestruturas. Essa qualidade evolui no tempo, essencialmente em função do tráfego e das condições atmosféricas, os quais contribuem para a degradação dos elementos da via e da respetiva fundação. Neste contexto, a deformação permanente das camadas de apoio da via (balastro, sub-balastro e camadas da...
A análise mecanicista da via-férrea com base na evolução da qualidade geométrica, não só constitui uma forma de avaliar o desempenho atual, como poderá permitir estimar a evolução do comportamento da estrutura e das características dos diversos elementos que a compõem, possibilitando assim otimizar as intervenções de manutenção e reabilitação. Através de uma modelação numérica do comportamento da via-férrea que...