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A Primeira Revolução Industrial iniciada no século XVIII é considerada atualmente como um dos grandes marcos da história moderna. Deste período subsistem até aos dias de hoje diversas máquinas que representam a memória dessa era e que têm vindo a suscitar a atenção de áreas como a de conservação e restauro. No entanto, a conservação deste tipo máquinas, especialmente as que ainda funcionam, requer uma atenção mais especializada, sendo neste contexto que as áreas da engenharia mecânica podem prestar um serviço fundamental. Aplicando técnicas modernas e conhecimentos aprofundados sobre o funcionamento dos mecanismos mais antigos, é possível fazer uma caracterização do comportamento dinâmico, uma determinação de propriedades mecânicas e uma análise mais rigorosa do estado de condição desses equipamentos. É neste sentido que surge o tema desta dissertação de mestrado. Tendo por base uma proposta do projeto IH4Future do LIBPhys – UNL (Departamento de Física da FCT), e da Câmara Municipal do Seixal, foi realizado um estudo em torno de um conjunto de objetos existente na Fábrica de Pólvora de Vale de Milhaços, constituído por uma máquina a vapor, com mais de um século, e as tubagens, caldeiras e bombas de água que fazem parte do seu funcionamento. O estudo realizado assenta numa caracterização do funcionamento deste conjunto, através da aplicação de técnicas de manutenção preventiva, como a análise de vibrações e de temperaturas (termografia e medição com sensores). Com um interesse essencialmente histórico e cultural, a recuperação desta máquina a vapor e a possibilidade de a manter em condição operacional, na instalação industrial onde foi originalmente implantada, visa a preservação do património industrial, abrindo eventualmente um caminho à conservação e entendimento destes objetos históricos, assente na comunhão entre os conhecimentos provenientes das áreas de conservação, restauro e materiais e os conhecimentos e técnicas da área de engenharia mecânica. O presente estudo apresenta o trabalho desenvolvido para a recolha, processamento e análise dos dados sobre vibrações e temperatura medidos in situ, com a máquina em funcionamento, assim como os resultados obtidos e algumas considerações conclusivas, podendo esta avaliação inicial constituir uma situação de referência para os trabalhos futuros a desenvolver. The industrial revolution initiated in the 18th century is considered to be one of the greatest landmarks of modern history. From that period, several ancient machines that represent the memory of that era subsist until the present days and have been attracting the attention of areas such as conservation and restoration. However, the preservation of this type of machines, especially those that are intended to maintain operational, requires a more specialized attention justifying the fundamental collaboration of areas like mechanical engineering. Applying modern techniques and in-depth knowledge about the functioning of ancient mechanisms, it is possible to characterize the dynamic behavior, determine mechanical properties and more rigorously analyze the condition of these equipments. Thus, arises the theme of this master's thesis. Based on a proposal of the IH4Future project by LIBPhys - UNL (FCT Physics Department), and by the Seixal City Council, a study was carried out around a set of objects existing in the Vale de Milhaços gunpowder plant, consisting of a steam engine, more than a century old, and the pipes, boilers and water pumps that are part of its operation. The study carried out is based on a characterization of the operation of this set, through the application of predictive maintenance techniques, such as the analysis of vibrations and temperatures (thermography and measurement with sensors). From an historical and cultural interest point of view, the restoration of this steam engine and the possibility of maintaining it in an acceptable operating condition, in the location where it was originally installed, aims the preservation of the industrial patrimony, eventually creating a path for the conservation and understanding of these historical objects, based on the knowledge communion of Conservation, Restoration, Materials and the Mechanics fields. This study presents the work developed for acquisition, processing and analysis of vibrations and temperature data, obtained from the steam machine in operating conditions (study object), as well as the obtained results and some conclusive considerations. This initial assessment may constitute a reference situation for future work.

Material, Culture, Scientific Culture: Industrial Heritage for the Future, Wain, A., Castro, D., Rollo, M. F., Nogueira, F., Santos, G., Filipe, M. D. G., Tissot, I., Sampaio, J. M., Santos, J. P., Lemos, M., Manso, M., Tissot, M., Guerra, M., Oglethorpe, M., Amaro, P., Pedroso, P., Silva, R., Pessanha, S., & Silva, T. A. N. (2021). «Cultura Material, Cultura Científica: Património Industrial para o Futuro.» Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa. e-ISBN: 978-972-8893-97-2

Technical textiles and functional garment assemblies can be engineered to optimize the protection against heat, flame, molten metal, static electricity, electromagnetic radiation, chemical agents, among others. The present work aims to study the use of wool-based fabrics as a fibrous substrate for thermal and electric protection by surface functionalization with Graphene Nanoplatelets (GNP’s) in polymeric-based dispersions. Wool fabrics were functionalized with 1% GNPs dispersed in chitosan and polyurethane, using impregnation and coating techniques. The results show that wool fabrics coated with polyurethane (PU) functionalized with 1% GNPs present an interesting approach regarding multiscale protection., The authors would like to express appreciation for the support of Portugal2020 for funding the project nº 038328,” MultiscaleProtech”, granted by Fundo Europeu do Desenvolvimento Regional (FEDER). Are also thankful to CEECIND/02803/2017 and UID/CTM/00264/2019 funded by National Founds through FCT/MCTES.

Chronic wounds, pressure sores, lesions, and infections of microbial origin in bedridden, paralyzed, or malnutrition patients remain the object of study of many researchers. A variety of factors behind the development of these disorders are related to the patient's immune system, making it unable to respond effectively to the treatment of the wound. These factors can be properly controlled, giving particular importance to the ethiology and stage of the wound, as well as the time periods corresponding to the replacement of the dressings. The present research reports a novel foam/soft material, L-Cys-g-PCL, with an application for decubitus/pressure ulcers, especially for wounds with a difficult healing process due to infections and constant oxidation of the soft tissues. During this work, the interactions between S. aureus and L-Cys-g-PCL foam were studied under conditions that simulate decubitus ulcers; namely, pH and exudate. The effects of duration of grafting (1 or 8 h) and pH (7.0 and 8.9) on wettability, surface energy, swelling, and porosity were also evaluated. Results showed an effective microbicidal activity exhibiting an inhibition ratio of 99.73% against S. aureus. This new L-Cys-g-PCL soft material showed saftey to contact skin, ability to be shaped to fill in sunken holes (craters) - pressure ulcers stage III - and to act as a smart material responsive to pH, which can be tailored to develop better swelling properties at alkaline pH where exudates are normally higher, so as to address exudate self-cleaning and prevention of desiccation..

A novel dressing material – silk fibroin fabric (SF)- l -Cysteine ( l -Cys) – is here developed to be used as standard treatment for atopic dermatitis (AD), which combines comfort, thermic, and tensile strength properties of silk materials with antioxidant and antimicrobial effects of l -Cys. A careful understanding about the linking strategies is needed in order not to compromise the bioavailability of l -Cys and deplenish its bioactivity. Durability was also addressed through washing cycles and compared with hospital requirements, according to international Standard EN ISO 105-C06:2010. The present research also analyze the interactions between Staphylococcus aureus and SF- l -Cys under simulating conditions of AD and demonstrated the effectiveness of a double covalent grafting, with the importance of SF tyrosine (Tyr) covalent linkage with l -Cys (SF-g- l -Cys/Tyr-g- l -Cys) even after several washing cycles, twenty five, whereas for a disposable application a single covalent mechanism of grafting l -Cys proved to be sufficient (SF-g- l -Cys). Results showed effective antimicrobial activities exhibiting higher inhibition ratios of 98.65% for SF-g- l -Cys after 5 washing cycles, whereas 97.55% for SF-g- l -Cys/Tyr-g- l -Cys after 25 washing cycles, both at pH 9.5 grafting strategy. Furthermore, it is also reported a non-protumoral effect of l -Cys. A new advance is herein achieved at the world of medical antimicrobial textiles tailored to address wound moisture environment and exudate self-cleaning, which may open novel applications as complementary therapy for AD disease.

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New advances have been released in textile industry. Contributions at the level of textile fiber chains engineering has allowed modification of their structure, production of smart polymers responding to changes in environment, and attachment or entrapment of cells and bioactive molecules. Likewise, our society high demand of hygienic patterns, has raised the intensive research and development of antimicrobial textiles. Applications are being extended to underwear, sportswear, home furnishing, protective clothes, wound-dressings and in areas with high risk of microbial infection, as hospitals, schools and hotels. Throughout last decades hospitals have faced tough challenges concerning microbial multi-resistance, especially in immunodepressed patients. The strongest cause for microbial resistance may be due to the abuse of antibiotics uptake, either by humans to treat something non appropriately, as by animals, to earn weight. The development of antimicrobial textiles arise as a promising solution that may significantly decrease the risk of nosocomial infections. Several antimicrobial agents have been applied in textiles, namely quaternary ammonium compounds, silver, polyhexamethylene biguanides and triclosan. However, they have shown a reduced spectrum of microbial inhibition which cause resistances, cytotoxicity causing skin irritation, as well as toxic to the environment. Furthermore, these compounds gradually lose their bioactivity with use and launderings. L-cysteine (L-Cys) that is found in several living organisms is a natural defensive thiolated aminoacid never studied before as a potential antimicrobial agent for textiles, which can grant antibacterial properties without cytotoxicity. Furthermore, antimicrobial peptides (AMPs) belong to innate immune system of multicellular organisms and appear as an alternative to antibiotics. They are small, amphipathic, and strongly cationic which bind to negatively charged phospholipid headgroups of microbial membranes. Although the mechanism of AMPs-microbial killing is still not known, many hypotheses have been proposed: (i) membrane depolarization, (ii) formation of physical holes at the membrane, (iii) programmed bacterial death processes, (iv) phospholipidic redistribution, and (v) internalization of the AMP. They have broad-spectrum antimicrobial activity. Once their target is the bacterial membrane microorganisms hardly develop resistance, otherwise they would have to change all their lipidic composition and/or organization, which is high demanding and not energetically worth it. During this work, non-covalently adsorbed L-Cys to wool (patent PAT 104540 A) and to cotton showed to be non-toxic to human cells, and had antimicrobial effects against Gram-negative and Gram-positive bacteria and its main mechanism of action on cotton was assessed by flow citometry. Antimicrobial peptides (AMPs) will also be immobilized on textiles, in order to find if textile imobilized-AMP can attract and kill bacteria. Natural polymers have shown few adverse reactions, once they have excellent humidity control, biocompatibility and low-allergic responses, due to their similarity to macromolecules which biological environment is prepared to recognize and to deal with metabolically. AMPs will be selected, based on their 3D structure, terminal charge and size. Best-studied AMPs are cationic due to their action on negative surface charged microorganisms. Evaluation of minimal inhibitory concentration (MIC) of AMPs will elucidate the amount of AMPs to be used to functionalize textile substrates and cytotoxicity studies will provide the toxicity of functionalized textiles to human cells. In order to develop long-lasting and washable functionalized textiles we propose the covalent binding of AMPs on textiles through selected chemistries already employed on surface modifying of medical devices elsewhere. Alternatively, we will use plasma treatment, which is usually used to modify many surface properties of polymeric materials. This study may allow the development of innovative antimicrobial textiles, simulating microbial-free microenvironments in order to develop, in the future, antimicrobial fabrics to avoid airborne spreading and improve patient’s quality of life in a hospital context.

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