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2020
Machado, J., Guojie Bian, Nancy Paul, M. Trassinelli, P. Amaro, M. Guerra, C. I. Szabo, A. Gumberidze, J. M. Isac, J. P. Santos, J. P. Desclaux, and P. Indelicato. "{Reference-free measurements of the 1s2s2p2P1/2,3/2o$\rightarrow$1s22s2S1/2and 1s2s2p4P5/2$\rightarrow$1s22s2S1/2transition energies and widths in lithiumlike sulfur and argon ions}." Physical Review A. 101 (2020): 062505. AbstractWebsite
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Centeno, Pedro, Miguel F. Alexandre, Manuel Chapa, Joana V. Pinto, Jonas Deuermeier, Tiago Mateus, Elvira Fortunato, Rodrigo Martins, Hugo Águas, and Manuel J. Mendes. "{Self-Cleaned Photonic-Enhanced Solar Cells with Nanostructured Parylene-C}." 2000264 (2020): 1-9. Abstract

Abstract Photonic front-coatings with self-cleaning properties are presented as means to enhance the efficiency and outdoor performance of thin-film solar cells, via optical enhancement while simultaneously minimizing soiling-related losses. This is achieved by structuring parylene-C transparent encapsulants using a low-cost and highly-scalable colloidal-lithography methodology. As a result, superhydrophobic surfaces with broadband light-trapping properties are developed. The optimized parylene coatings show remarkably high water contact angles of up to 165.6° and extremely low adhesion, allowing effective surface self-cleaning. The controlled nano/micro-structuring of the surface features also generates strong anti-reflection and light scattering effects, corroborated by numeric electromagnetic modeling, which lead to pronounced photocurrent enhancement along the UV?vis?IR range. The impact of these photonic-structured encapsulants is demonstrated on nanocrystalline silicon solar cells, that show short-circuit current density gains of up to 23.6%, relative to planar reference cells. Furthermore, the improvement of the devices' angular response enables an enhancement of up to 35.2% in the average daily power generation.

Mendes, Manuel J., Olalla Sanchez-Sobrado, Sirazul Haque, Tiago Mateus, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{Wave-optical front structures on silicon and perovskite thin-film solar cells}." Solar Cells and Light Management. Elsevier, 2020. 315-354. Abstract
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2019
Torres-González, Arturo, Alfonso Alcántara, Vasco Sampaio, Jesús Capitán, Bruno Guerreiro, Rita Cunha, and Anibal Ollero. "Distributed Mission Execution for Aerial Cinematography with Multiple Drones." Workshop on Signal Processing Computer vision and Deep Learning for Autonomous Systems, EUSIPCO2019. 2019. Abstract
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Agra, Agostinho, Jorge Orestes Cerdeira, and Cristina Requejo. "A computational comparison of compact {MILP} formulations for the zero forcing number." Discrete Applied Mathematics. 269 (2019): 169-183. AbstractWebsite
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Martins, Lu{\'ıs, Pedro Amaro, Sofia Pessanha, Mauro Guerra, Jorge Machado, Maria Luisa Carvalho, and José Paulo Santos. "{Multiconfiguration Dirac–Fock calculations of Zn K-shell radiative and nonradiative transitions}." X-Ray Spectrom.. 48 (2019): 212-8. AbstractWebsite

Zinc K-shell radiative and radiationless transition rates are calculated using the multiconfiguration Dirac–Fock method. Correlation up to the 4p orbital is included in almost all transition rate cal...

Brites, Maria João, Maria Alexandra Barreiros, Victoria Corregidor, Luis C. Alves, Joana {V. Pinto}, Manuel J. Mendes, Elvira Fortunato, Rodrigo Martins, and João Mascarenhas. "{Ultrafast Low-Temperature Crystallization of Solar Cell Graded Formamidinium-Cesium Mixed-Cation Lead Mixed-Halide Perovskites Using a Reproducible Microwave-Based Process}." ACS Applied Energy Materials. 2 (2019): 1844-1853. AbstractWebsite
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Śniatała, Paweł, Dawid Makowski, João Goes, Witold Machowski, and Sergio Salas Arriarán. "Improving Dual-Slope A/D Converter with Noise-Shaping and Digital Filtering Techniques." 26th IEEE International Conference on Mixed Design of Integrated Circuits and Systems. IEEE, 2019.
Chapa, Manuel, Miguel F. Alexandre, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{All-Thin-Film Perovskite/C-Si Four-Terminal Tandems: Interlayer and Intermediate Contacts Optimization}." ACS Applied Energy Materials. 2 (2019): 3979-3985. Abstract

Combined perovskite/crystalline-silicon four-terminal tandem solar cells promise {\textgreater}30{%} efficiencies. Here we propose all-thin-film double-junction architectures where high-bandgap perovskite top cells are coupled to ultrathin c-Si bottom cells enhanced with light trapping. A complete optoelectronic model of the devices was developed and applied to determine the optimal intermediate layers, which are paramount to maximize the cells' photocurrent. It was ascertained that by replacing the transparent conductive oxides by grid-based metallic contacts in the intermediate positions, the parasitic absorption is lowered by 30{%}. Overall, a 29.2{%} efficiency is determined for ∼2 um thick tandems composed of the optimized interlayers and improved with Lambertian light trapping.

Clemente, Pedro, Marta Calvache, Paula Antunes, Rui Santos, Jorge Orestes Cerdeira, and Maria João Martins. "Combining social media photographs and species distribution models to map cultural ecosystem services: The case of a Natural Park in Portugal." Ecological Indicators. 96 (2019): 59-68. AbstractWebsite
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Torrisi, Giacomo, João S. Luis, Olalla Sanchez-Sobrado, Rosario Raciti, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, Rodrigo Martins, and Antonio Terrasi. "{Colloidal-structured metallic micro-grids: High performance transparent electrodes in the red and infrared range}." Solar Energy Materials and Solar Cells. 197 (2019): 7-12. Abstract

One of the most promising approaches to produce industrial-compatible Transparent Conducting Materials (TCMs) with excellent characteristics is the fabrication of TCO/metal/TCO multilayers. In this article, we report on the electro-optical properties of a novel high-performing TCO/metal/TCO structure in which the intra-layer is a micro-structured metallic grid instead of a continuous thin film. The grid is obtained by evaporation of Ag through a mask of polystyrene colloidal micro-spheres deposited by the Langmuir-Blodgett method and partially dry-etched in plasma. IZO/Ag grid/IZO structures with different thicknesses and mesh dimensions have been fabricated, exhibiting excellent electrical characteristics (sheet resistance below 10 $Ømega$/□) and particularly high optical transmittance in the near-infrared spectral region as compared to planar (unstructured) TCM multilayers. Numerical simulations were also used to highlight the role of the Ag mesh parameters on the electrical properties.

Alexandre, Miguel, Manuel Chapa, Sirazul Haque, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{Optimum Luminescent Down-Shifting Properties for High Efficiency and Stable Perovskite Solar Cells}." ACS Applied Energy Materials. 2 (2019): 2930-2938. AbstractWebsite
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Pardoux, R., A. Fiévet, C. Carreira, C. Brochier-Armanet, O. Valette, Z. Dermoun, B. Py, A. Dolla, S. R. Pauleta, and C. Aubert. "The bacterial MrpORP is a novel Mrp/NBP35 protein involved in iron-sulfur biogenesis." Scientific Reports. 9.1 (2019). AbstractWebsite
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Khili, Faouzia, Joao Borges, Pedro L. Almeida, Rabah Boukherroub, and Amel Dakhlaoui Omrani. "Extraction of cellulose nanocrystals with structure I and II and their applications for reduction of graphene oxide and nanocomposite elaboration." 10.7 (2019): 1913-1927. Abstract
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Boavida, Nuno, António Moniz, Juan Aransanz, Pablo Sanz de Miguel, Maria Caprile, Julia Frias, Linda Nierling, Bettina-Johanna Krings, Leon Küstermann, Csaba Makó, Miklós Illéssy, and Katalin Bácsi Work in digital platforms: Literature review from Germany, Hungary, Portugal and Spain. Lisbon: CICS.NOVA, 2019. Abstract

This 1st Report of the project CrowdWork21 presents a summary of the information collected about workers in digital platforms by country (German, Hungary, Portugal and Spain). Each national report describes first the scientific debates about workers of digital platforms. After, the reports present the information collected about the national public debates and identifies the angles normally covered by the media in relation to the organisation of digital workers. Lastly, the reports present initial conclusions about the information collected in each country.

Araújo, João. "All publications." (2019).
Viana, L. A., Nunes A. Antão, Vicente M. da Silva, and N. M. C. Guerra The application of limit analysis to the study of the basal failure of deep excavations in clay considering the spatial distribution of soil strength. Proceedings of the 17 European Conference on Soil Mechanics and Geotechnical Engineering. Reykjavik, Islândia, 2019.
Micaelo, R., J. Neves, Mauro Antunes, and D. Aelenei. "Avaliação experimental das propriedades térmicas de misturas betuminosas." 2º Congresso de Ensaios e Experimentação em Engenharia Civil. Porto 2019. Abstract

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Almeida, André F. O., António P. Ramos, Válter Lúcio, and Rui Marreiros. "Behavior of RC flat slabs with shear bolts under reversed horizontal cyclic loading." Structural Concrete (2019). AbstractWebsite

Abstract An experimental work on reinforced concrete flat slab specimens to test the efficiency of postinstalled bolts, as punching shear reinforcement in resisting vertical and cyclic horizontal loads, was conducted and is presented in this paper. The test protocol consisted in increasing horizontal drifts combined with constant vertical load until failure. Two different detailing solutions for the shear reinforcement were considered, one using a radial distribution around the column and another using a cross distribution, being the results compared with a previously tested reference specimen. The dimensions of the specimens were 4.25 x 1.85 x 0.15 m3. The test setup used for these tests was developed by the research team and simulates the boundary conditions with already recognized good results. Postinstalled steel bolts were proven to be an efficient solution for strengthening of existing structures, improving the structural behavior, and the punching resistance.

Almeida, André F. O., António P. Ramos, Válter Lúcio, and Rui Marreiros. "Behavior of RC flat slabs with shear bolts under reversed horizontal cyclic loading." Structural Concrete. n/a (2019). AbstractWebsite

Abstract An experimental work on reinforced concrete flat slab specimens to test the efficiency of postinstalled bolts, as punching shear reinforcement in resisting vertical and cyclic horizontal loads, was conducted and is presented in this paper. The test protocol consisted in increasing horizontal drifts combined with constant vertical load until failure. Two different detailing solutions for the shear reinforcement were considered, one using a radial distribution around the column and another using a cross distribution, being the results compared with a previously tested reference specimen. The dimensions of the specimens were 4.25 x 1.85 x 0.15 m3. The test setup used for these tests was developed by the research team and simulates the boundary conditions with already recognized good results. Postinstalled steel bolts were proven to be an efficient solution for strengthening of existing structures, improving the structural behavior, and the punching resistance.

Azanza, Moreno M., R. Coimbra, E. Puértolas-Pascual, J. Russo, B. Bauluz, and O. Mateus Crystallography of Lourinhanosaurus eggshells (Dinosauria, Theropoda, Allosauroidea). Journal of Vertebrate Paleontology, Program and Abstracts., 2019.moreno_azanza_et_al_2019_svp_abstract.pdf
Hendrickx, Christophe, Octávio Mateus, Ricardo Araújo, and Jonah Choiniere. "The distribution of dental features in non-avian theropod dinosaurs: Taxonomic potential, degree of homoplasy, and major evolutionary trends." Palaeontologia Electronica. 22.3 (2019): 1-110. Abstractthe_distribution_of_dental_features_in_non-avian_t.pdfWebsite

Isolated theropod teeth are some of the most common fossils in the dinosaur fossil record and are continually reported in the literature. Recently developed quantitative methods have improved our ability to test the affinities of isolated teeth in a repeatable framework. But in most studies, teeth are diagnosed on qualitative characters. This can be problematic because the distribution of theropod dental characters is still poorly documented, and often restricted to one lineage. To help in the identification of isolated theropod teeth, and to more rigorously evaluate their taxonomic and phylogenetic potential, we evaluated dental features in two ways. We first analyzed the distribution of 34 qualitative dental characters in a broad sample of taxa. Functional properties for each dental feature were included to assess how functional similarity generates homoplasy. We then compiled a quantitative data matrix of 145 dental characters for 97 saurischian taxa. The latter was used to assess the degree of homoplasy of qualitative dental characters, address longstanding questions on the taxonomic and biostratigraphic value of theropod teeth, and explore the major evolutionary trends in the theropod dentition.

In smaller phylogenetic datasets for Theropoda, dental characters exhibit higher levels of homoplasy than non-dental characters, yet they still provide useful grouping information and optimize as local synapomorphies of smaller clades. In broader phylogenetic datasets, the degree of homoplasy displayed by dental and non-dental characters is not significantly different. Dental features on crown ornamentations, enamel texture and tooth microstructure have significantly less homoplasy than other dental features and can be used to identify many theropod taxa to ‘family’ or ‘sub-family’ level, and some taxa to genus or species. These features should, therefore, be a priority for investigations seeking to classify isolated teeth.

Our observations improve the taxonomic utility of theropod teeth and in some cases can help make isolated teeth useful as biostratigraphic markers. This proposed list of dental features in theropods should, therefore, facilitate future studies on the systematic paleontology of isolated teeth.

Rebelo, Hugo Bento, Filipe Amarante dos Santos, Corneliu Cismasiu, and Duarte Santos. "Exploratory study on geodesic domes under blast loads." International Journal of Protective Structures (2019).