Is Poly(Methyl Methacrylate) (PMMA) a suitable substrate for ALD?: A review

Poly (methyl methacrylate) (PMMA) is a thermoplastic synthetic polymer, which displays superior characteristics such as transparency, good tensile strength, and processability. Its performance can be improved by surface engineering via the use of functionalized thin film coatings, resulting in its versatility across a host of applications including, energy harvesting, dielectric layers and water purification. Modification of the PMMA surface can be achieved by atomic layer deposition (ALD), a vapor-phase, chemical deposition technique, which permits atomic-level control. However, PMMA presents a challenge for ALD due to its lack of active surface sites, necessary for gas precursor reaction, nucleation, and subsequent growth. The purpose of this review is to discuss the research related to the employment of PMMA as either a substrate, support, or masking layer over a range of ALD thin film growth techniques, namely, thermal, plasma-enhanced, and area-selective atomic layer deposition. It also highlights applications in the selected fields of flexible electronics, biomaterials, sensing, and photocatalysis, and underscores relevant characterization techniques. Further, it concludes with a prospective view of the role of ALD in PMMA processing.e Fundação para a Ciência e Tecnologia (FCT, Portugal)/PIDDAC through the Strategic Funds project reference UIDB/04650/2020-2023. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTE

Characterization of wine fermentations using fiber optic LWUV-Vis-SWNIR spectroscopy

Spectroscopy is widely used in biological sciences, being applied to liquids, pastes, powders, films, fibers, gases and surfaces. It makes possible to characterize proteins, peptides, lipids, membranes and carbohydrates in pharmaceuticals, foods, plants or animal tissues. It can also provide detailed information about the structure and mechanism of action of molecules. In this work we explore the use of fiber optics UV-VISSWNIR spectroscopy to characterize grape must fermentations of 114 different Saccharomyces cerevisiae strains. Results show that fiber optics UVVIS- SWNIR spectroscopy is a robust technique for characterize different wine fermentations, being able to characterize and differentiate the fermentation of different strains of S. cerevisiae based on their origins, by each spectroscopic fingerprint

Efeito de flutuações de composição química nas transformações dos aços: aplicação a um aço-ferramenta DIN X 38 CrMoV 51

Dissertação apresentada para obtenção do grau de Doutor em Ciência dos Materiais, especialidade de Metalurgia, pela Universidade Nova de Lisboa, Faculdade de Ciências e TecnologiaPropõe-se, um método alternativo para a caracterização de flutuações de composição química nos aços. Para esse fim, é utilizado o desvio observado na cinética martensítica relativamente à cinética proposta por Koistinen-Marburger (considerada, à partida, como válida em aços de composição homogénea). Desse modo, as flutuações de composição serão traduzidas por flutuações na temperatura Ms. Para o efeito, considerou-se que a temperatura Ms segue uma distribuição gaussiana. A metodologia proposta foi aplicada a um aço-ferramenta laminado a quente, apresentando uma estrutura bandeada de grau considerado como mediano. A avaliação da cinética martensítica do aço foi efectuada por dilatometria. Após conversão do desvio padrão de Ms num desvio padrão para o teor de carbono equivalente, a comparação dos resultados obtidos por este método, com os resultados obtidos por microanálise química e microdurezas Vickers, foi satisfatória. A caracterização das bandas de segregação no material (por metalografia, microanálise química, microdurezas Vickers e métodos topográficos sobre amostras temperadas), pôs em evidência diferentes níveis de flutuações (traduzidos pelo comprimento de onda médio). Nomeadamente, verificou-se que o comprimento de onda médio para as flutuações químicas do carbono e dos elementos carburígenos era diferente. Esta conclusão veio reforçar o interesse numa caracterização mais precisa da distribuição do carbono, dada a importância desse elemento nas transformações de fase dos aços. Paralelamente, efectuou-se um estudo teórico das variações dimensionais associadas às transformações observadas no tratamento térmico desse aço-ferramenta. Para esse fim, utilizaram-se dados cristalográficos encontrados na literatura para as fases intervenientes. O efeito das variações de composição nas soluções sólidas foi também considerado. Este estudo permitiu uma melhor interpretação das curvas dilatométricas observadas nos respectivos ciclos térmicos

Study of an Iron Age Gilded Silver Earring by XRF, SEM-EDS and Multifocus OM

Funding Information: This research was funded by National Funds through FCT (Fundação para a Ciência e Tecnologia) under the scope of the Gold.PT project (2022.02608.PTDC) and the project UIDB/50025/2020–2023 to CENIMAT/i3N. Publisher Copyright: © 2023 by the authors.The use of gold for artefact productions underwent substantial developments during Iron Age in western Europe, with the diversification of alloy compositions and the introduction of new technologies and aesthetics. This work presents a detailed study of a Late Iron Age earring from the western Iberian Peninsula and a discussion taking into consideration the alloys and technologies used at the time. The earring has a complex structure, composed of block- and strip-twisted wires and granulation. Characterization by multifocus optical microscopy, portable X-ray fluorescence spectrometry (pXRF), micro-XRF and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) were performed to obtain information on the chemical composition and manufacturing techniques. Results show that the earring was manufactured with wires and granules made of a silver-rich alloy, covered with a gold-rich layer 45 (Formula presented.) m thick on average, which acted as an external coating making the entire earring resemble gold. This is a rare example of an Iron Age gilded earring, and its detailed study provides further information on the manufacturing solutions adopted by the Iron Age goldsmiths.publishersversionpublishe

X-metabolomics : a software tool for dynamic mass spectroscopy automated signal processing

One of the major challenges of today's biotechnology is to be able to obtain the maximum of metabolic information for the holistic interpretation of biological systems. Herein we present a new computational application for gas-chromatography mass spectroscopy automated signal processing, named 'X-Metabolomics', that shows to be a potential framework for dynamic systems as fermentation processes interpretation by compounds and pathways identification and quantification and moreover for new metabolites discovery. Our GC-MS signal processing pipeline is implemented into an X-window interface using Tcl/Tk interface and based on R statistical programming environment for comprehensive statistical computing of results and access to 'Bioconductor' bioinformatics platform under Unix, Linux and MacOS. This approach focuses on the robustness of peak extraction algorithms for further identification, quantification and biological interpretation by multivariate analysis, evolving the following steps: i) peaks extraction; ii) supervised filtering; iii) identification of candidate fragments and removal of possible contaminants; iv) compounds identification/quantification; v) compounds expression and co-expression in time-course; and vi) sample classification and biological interpretation by multivariate analysis. 'X-Metabolomics' can be an useful tool in different fields such as pharmacology, genetics, living cells systems, promising to be innovative and very helpful for new drug discovery and new advances in dynamic systems understanding

Characterisation of Archaeological High-tin Bronze Corrosion Structures

Part of this work was carried out in the framework of the projects: 'Singing Bronze', funded by Banco Santander through the prize Santander/NOVA 2016; 'IberianTin' (PTDC/HAR-ARQ/32290/2017), funded by European Regional Development Fund funds through the regional program of Lisbon and through national funds through the Fundacao para a Ciencia e a Tecnologia (FCT) (Foundation for Science and Technology); UID/CTM/50025/2019 granted to CENIMAT/i3N, financed through FEDER funds by COMPETE 2020 and national funds through FCT.Since ancient times, the use of high-tin bronze alloys (>17 wt.%) has been mainly limited to the production of specific objects such as mirrors and bells. High-tin bronzes can show distinctive colour reflection, as well as mechanical properties and corrosion resistance that clearly distinguish them from the classical bronze composition (with 8–12 wt.% tin). In the present study samples of archaeological high-tin bronze bells were studied by optical microscopy, SEM-EDX, and Raman imaging with the aim of characterising their microstructural long-term corrosion patterns. Results show the presence of high quantities of δ phase, when compared to the classical bronze composition, which makes some corrosion structures more visible in these alloys. The corrosion morphologies show selective corrosion of different metal phases along depth of corrosion, which were attributed to different oxygen potentials. This study proposes a classification of four types of corrosion structures occurring in two-phase bronzes as a consequence of aeration conditions during burial time and aeration within the corrosion structure.authorsversionepub_ahead_of_prin

Roman situlae from Conimbriga (Portugal): Compositional and microstructural characterization of anthropomorphic handle attachments

info:eu-repo/semantics/publishedVersio

Concepção e desenvolvimento de sistemas biotecnológicos

In a simple and succinct form the authors intend to present the research and development activities that are being undertaken at the University of Minho in the area of biotechnology applied to the study, design, development and construction of equipment goods, which are being carried out together with important Iberian and European industrial companies. The projects are as follows: • Real time monitoring of beer fermentation using optical fiber sensors – MONI®TOR; • EggReady – Development of a prototype for a continuous industrial production of fried eggs, and • HealthyCream – Development of innovative dietetical solutions for the deli shop industry. These projects have been submitted and approved, and are all funded by the Portuguese National Strategic Reference Framework (QREN operational programmes 2007-2013). They are being developed with the following partner companies, all based in Portugal: UNICER Bebidas, S.A. – Innovation and Quality Department (Leça do Balio, Matosinhos); Derovo – Derivados de Ovos, S.A. (Pombal); Decorgel, S.A. (Trofa); Valinox – Indústrias Metalúrgicas, Lda. (Arouca), and the Departments of Biological Engineering (Braga) and Mechanical Engineering (Guimarães), School of Engineering, University of Minho.Pretende-se dar a conhecer, de uma forma simples e sucinta, os projectos de investigação e desenvolvimento que decorrem, actualmente, na Universidade do Minho, na área da biotecnologia aplicada ao estudo, concepção, projecto, desenvolvimento e construção de tecido industrial ibérico e europeu. Os projectos são: · Monitorização em tempo real da fermentação de cerveja na região do UV-Vis e IVPOC (SWNIR) com recurso a sondas de fibra óptica – MONI®TOR”; · EggReady - Protótipo para produção industrial, em contínuo, de ovos estrelados para consumo no canal HORECA, e · HealthyCream - Desenvolvimento de soluções dietéticas inovadoras para a indústria de pastelaria. Estes projectos foram submetidos e aprovados, sendo financiados pelo programa de incentivos do Quadro de Referência Estratégico Nacional Português, QREN (2007-2013). Estão a ser realizados em parceria com as empresas UNICER Bebidas, S.A. – Núcleo de Investigação e Desenvolvimento (Leça do Balio, Matosinhos); Derovo – Derivados de Ovos, S.A. (Pombal); Decorgel, S.A. (Trofa); Valinox – Indústrias Metalúrgicas, Lda. (Arouca), e os Departamentos de Engenharia Biológica (Braga) e Engenharia de Mecânica (Guimarães) da Escola de Engenharia da Universidade do Minho, todas estas instituições sediadas em Portugal