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2023
Rogério, Flávio, Armando Antão N. Nuno M. C. Guerra, and Manuel Matos Fernandes. "PROBABILIDADE DE ROTURA DE TALUDES DE ESCAVAÇÃO DIMENSIONADOS DE ACORDO COM O EUROCÓDIGO 7. ESTUDO EXPLORATÓRIO." 2023. Abstract
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Rotatori, FM, A. A. Chiarenza, M. Moreno-Azanza, and O. Mateus Rise of a dinasty: macroevolutionary and biogeographic patterns of iguanodontian dinosaurs across the Jurassic–Cretaceous transition. EAVP Annual Conference of the European Association of Vertebrate Palaeontologists. Palaeovertebrata, Special Volume 1-23. DOI: 10.18563/pv.eavp2023, 2023. Abstract
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Ramos, António, Brisid Isufi, and Rui Marreiros. "SEISMIC BEHAVIOR OF SLAB–COLUMN CONNECTIONS USING HIGH PERFORMANCE FIBER REINFORCED CONCRETES." American Concrete Institute, ACI Special Publication. Vol. SP-357. 2023. 123-138. Abstract
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Ramos, António Pinho, Brisid Isufi, Rui Marreiros, Dario Coronelli, Teresa Netti, Marco Lamperti Tornaghi, Georgios Tsionis, and Aurelio Muttoni. "Seismic Performance of Strengthened Slab-Column Connections in a Full-Scale Test." Journal of Earthquake Engineering. 27 (2023): 2299-2318. AbstractWebsite
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Ribeiro, G., G. Ferreira, U. D. Menda, M. Alexandre, M. J. Brites, M. A. Barreiros, S. Jana, H. Águas, R. Martins, P. A. Fernandes, P. Salomé, and MJ Mendes. "Sub-Bandgap Sensitization of Perovskite Semiconductors via Colloidal Quantum Dots Incorporation." Nanomaterials. 13 (2023). AbstractWebsite
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Menda, U. D., G. Ribeiro, J. Deuermeier, E. López, D. Nunes, S. Jana, I. Artacho, R. Martins, I. Mora-Seró, MJ Mendes, and I. Ramiro. "Thermal-Carrier-Escape Mitigation in a Quantum-Dot-In-Perovskite Intermediate Band Solar Cell via Bandgap Engineering." ACS Photonics. 10 (2023): 3647-3655. AbstractWebsite
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Coelho, João, Ricardo F. Correia, Sara Silvestre, Tomás Pinheiro, Ana C. Marques, Rosário M. P. Correia, Joana Vaz Pinto, Elvira Fortunato, and Rodrigo Martins. "{Paper-based laser-induced graphene for sustainable and flexible microsupercapacitor applications}." Microchimica Acta. 190 (2023): 1-10. Abstract

Laser-induced graphene (LIG) is as a promising material for flexible microsupercapacitors (MSCs) due to its simple and cost-effective processing. However, LIG-MSC research and production has been centered on non-sustainable polymeric substrates, such as polyimide. In this work, it is presented a cost-effective, reproducible, and robust approach for the preparation of LIG structures via a one-step laser direct writing on chromatography paper. The developed strategy relies on soaking the paper in a 0.1 M sodium tetraborate solution (borax) prior to the laser processing. Borax acts as a fire-retardant agent, thus allowing the laser processing of sensitive substrates that other way would be easily destroyed under the high-energy beam. LIG on paper exhibiting low sheet resistance (30 $Ømega$ sq−1) and improved electrode/electrolyte interface was obtained by the proposed method. When used as microsupercapacitor electrodes, this laser-induced graphene resulted in specific capacitances of 4.6 mF cm−2 (0.015 mA cm−2). Furthermore, the devices exhibit excellent cycling stability (> 10,000 cycles at 0.5 mA cm−2) and good mechanical properties. By connecting the devices in series and parallel, it was also possible to control the voltage and energy delivered by the system. Thus, paper-based LIG-MSC can be used as energy storage devices for flexible, low-cost, and portable electronics. Additionally, due to their flexible design and architecture, they can be easily adapted to other circuits and applications with different power requirements. Graphical Abstract: [Figure not available: see fulltext.]

Pinheiro, Ana, Andreia Ruivo, Marta Ferro, Joana Vaz Pinto, Jonas Deuermeier, Tiago Mateus, Ana Santa, Manuel J. Mendes, Rodrigo Martins, Sandra Gago, C. A. T. Laia, and Á. Hugo. "{Parylene-Sealed Perovskite Nanocrystals Down-Shifting Layer for Luminescent Spectral Matching in Thin Film Photovoltaics}." (2023). Abstract
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Duval, Louis, Rοbert Loetzsch, Heinrich Beyer, Dariusz Banaś, Perla Dergham, Jan Glorius, Robert E. Grisenti, Mauro Guerra, Alexandre Gumberidze, Pierre-Michel Hillenbrand, Paweł Jagodziński, Emily Lamour, Yuri Litvinov, Jorge Machado, Gerhard Paulus, Nancy Paul, Nikolaos Petridis, Jose-Paulo Santos, Marius Scheidel, Ragandeep S. Sidhu, Uwe Spillmann, Sébastien Steydli, Karol Szary, Sergiy Trotsenko, Ingo Uschmann, Günther Weber, Thomas Stöhlker, Paul Indelicato, and Martino Trassinelli. "{X-ray spectroscopy of few-electron uranium ions for tests of QED}." Proceedings of FAIR next generation scientists - 7th Edition Workshop — PoS(FAIRness2022). Vol. 419. 2023. 012. Abstract
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2022
Correia, Ricardo, Jonas Deuermeier, Maria Rosário Correia, Joana {Vaz Pinto}, João Coelho, Elvira Fortunato, and Rodrigo Martins. "{Biocompatible Parylene-C Laser-Induced Graphene Electrodes for Microsupercapacitor Applications}." ACS Applied Materials {&} Interfaces. 14 (2022): 46427-46438. AbstractWebsite
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Silva, Daniela, Catarina S. Monteiro, Susana O. Silva, Orlando Frazão, Joana V. Pinto, Maria Raposo, Paulo A. Ribeiro, and Susana Sério. "{Sputtering Deposition of TiO2 Thin Film Coatings for Fiber Optic Sensors}." Photonics. 9 (2022): 342. Abstract

Thin films of titanium dioxide (TiO2) and titanium (Ti) were deposited onto glass and optical fiber supports through DC magnetron sputtering, and their transmission was characterized with regard to their use in optical fiber-based sensors. Deposition parameters such as oxygen partial pressure, working pressure, and sputtering power were optimized to attain films with a high reflectance. The films deposited on glass supports were characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Regarding the deposition parameters, all three parameters were tested simultaneously, changing the working pressure, the sputtering power, and the oxygen percentage. It was possible to conclude that a lower working pressure and higher applied power lead to films with a higher reflectance. Through the analysis of the as-sputtered thin films using X-ray diffraction, the deposition of both Ti and TiO2 films was confirmed. To study the applicability of TiO2 and Ti in fiber sensing, several thin films were deposited in single mode fibers (SMFs) using the sputtering conditions that revealed the most promising results in the glass supports. The sputtered TiO2 and Ti thin films were used as mirrors to increase the visibility of a low-finesse Fabry–Perot cavity and the possible sensing applications were studied.

Rovisco, Ana, Maria Morais, Rita Branquinho, Elvira Fortunato, Rodrigo Martins, and Pedro Barquinha. "{Microwave-Assisted Synthesis of Zn2SnO4 Nanostructures for Photodegradation of Rhodamine B under UV and Sunlight}." Nanomaterials. 12 (2022): 2119. AbstractWebsite

The contamination of water resources by pollutants resulting from human activities represents a major concern nowadays. One promising alternative to solve this problem is the photocatalytic process, which has demonstrated very promising and efficient results. Oxide nanostructures are interesting alternatives for these applications since they present wide band gaps and high surface areas. Among the photocatalytic oxide nanostructures, zinc tin oxide (ZTO) presents itself as an eco-friendly alternative since its composition includes abundant and non-toxic zinc and tin, instead of critical elements. Moreover, ZTO nanostructures have a multiplicity of structures and morphologies possible to be obtained through low-cost solution-based syntheses. In this context, the current work presents an optimization of ZTO nanostructures (polyhedrons, nanoplates, and nanoparticles) obtained by microwave irradiation-assisted hydrothermal synthesis, toward photocatalytic applications. The nanostructures' photocatalytic activity in the degradation of rhodamine B under both ultraviolet (UV) irradiation and natural sunlight was evaluated. Among the various morphologies, ZTO nanoparticles revealed the best performance, with degradation > 90% being achieved in 60 min under UV irradiation and in 90 min under natural sunlight. The eco-friendly production process and the demonstrated ability of these nanostructures to be used in various water decontamination processes reinforces their sustainability and the role they can play in a circular economy.

Firmino, Rita, Emanuel Carlos, Joana Vaz Pinto, Jonas Deuermeier, Rodrigo Martins, Elvira Fortunato, Pedro Barquinha, and Rita Branquinho. "{Solution Combustion Synthesis of Hafnium-Doped Indium Oxide Thin Films for Transparent Conductors}." Nanomaterials. 12 (2022): 2167. AbstractWebsite

{\textless}p{\textgreater}Indium oxide (In2O3)-based transparent conducting oxides (TCOs) have been widely used and studied for a variety of applications, such as optoelectronic devices. However, some of the more promising dopants (zirconium, hafnium, and tantalum) for this oxide have not received much attention, as studies have mainly focused on tin and zinc, and even fewer have been explored by solution processes. This work focuses on developing solution-combustion-processed hafnium (Hf)-doped In2O3 thin films and evaluating different annealing parameters on TCO's properties using a low environmental impact solvent. Optimized TCOs were achieved for 0.5 M{%} Hf-doped In2O3 when produced at 400 °C, showing high transparency in the visible range of the spectrum, a bulk resistivity of 5.73 × 10−2 $Ømega$.cm, a mobility of 6.65 cm2/V.s, and a carrier concentration of 1.72 × 1019 cm−3. Then, these results were improved by using rapid thermal annealing (RTA) for 10 min at 600 °C, reaching a bulk resistivity of 3.95 × 10 −3 $Ømega$.cm, a mobility of 21 cm2/V.s, and a carrier concentration of 7.98 × 1019 cm−3, in air. The present work brings solution-based TCOs a step closer to low-cost optoelectronic applications.{\textless}/p{\textgreater}

Madeira, Ricardo MD, Tânia Vieira, Jorge C. Silva, Ivone R. Oliveira, João P. Borges, M. M. R. A. Lima, and Carmo M. Lança Piezoelectric Calcium Modified Barium Titanate for Bone Regeneration. Vol. 8. Materials Proceedings 2022, Vol. 8, Page 121, 8. Basel Switzerland: Multidisciplinary Digital Publishing Institute, 2022. Abstract

Solid state reaction was used to produced barium titanate modified with calcium (BCT) showing the presence of the piezoelectric tetragonal phase after sintering at 1350 °C. Bioglass 45S5 (BG) was synthetized by sol-gel route. From these two materials and commercial hydroxyapatite (HAp) were obtained composites. The BG produced showed some cytotoxic character that was weakened by passivation. All other materials were non-cytotoxic. Contact polarization at constant temperature was chosen composites polarization. Electric/dielectric properties were evaluated by thermally stimulated depolarization currents (TSDC). The material showed bioactivity with the composite with BCT/BG/HAp 90/5/5 (wt%) showing increased bioactivity. In vitro test showed high proliferation rates for the composites.

Mateus, Ayana, and Frederico Caeiro. "Improved Shape Parameter Estimation for the Three-Parameter Log-Logistic Distribution." Computational and Mathematical Methods. 2022 (2022): 1-13. AbstractWebsite
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Amaro, P., A. Adamczak, Abdou M. Ahmed, L. Affolter, F. D. Amaro, P. Carvalho, T. L. Chen, L. M. P. Fernandes, M. Ferro, D. Goeldi, T. Graf, M. Guerra, T. W. Hänsch, C. A. O. Henriques, Y. C. Huang, P. Indelicato, O. Kara, K. Kirch, A. Knecht, F. Kottmann, Y. W. Liu, J. Machado, M. Marszalek, R. D. P. Mano, C. M. B. Monteiro, F. Nez, J. Nuber, A. Ouf, N. Paul, R. Pohl, E. Rapisarda, J. M. F. dos Santos, J. P. Santos, P. A. O. C. Silva, L. Sinkunaite, J. T. Shy, K. Schuhmann, S. Rajamohanan, A. Soter, L. Sustelo, D. Taqqu, L. B. Wang, F. Wauters, P. Yzombard, M. Zeyen, and A. Antognini. "Laser excitation of the 1s-hyperfine transition in muonic hydrogen." SciPost Physics. 13 (2022). Abstract

The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen (μp) with 1 ppm accuracy by means of pulsed laser spectroscopy to determine the two-photon-exchange contribution with 2×10-4 relative accuracy. In the proposed experiment, the μp atom undergoes a laser excitation from the singlet hyperfine state to the triplet hyperfine state, then is quenched back to the singlet state by an inelastic collision with a H2 molecule. The resulting increase of kinetic energy after the collisional deexcitation is used as a signature of a successful laser transition between hyperfine states. In this paper, we calculate the combined probability that a μp atom initially in the singlet hyperfine state undergoes a laser excitation to the triplet state followed by a collisional-induced deexcitation back to the singlet state. This combined probability has been computed using the optical Bloch equations including the inelastic and elastic collisions. Omitting the decoherence effects caused by the laser bandwidth and collisions would overestimate the transition probability by more than a factor of two in the experimental conditions. Moreover, we also account for Doppler effects and provide the matrix element, the saturation fluence, the elastic and inelastic collision rates for the singlet and triplet states, and the resonance linewidth. This calculation thus quantifies one of the key unknowns of the HFS experiment, leading to a precise definition of the requirements for the laser system and to an optimization of the hydrogen gas target where μp is formed and the laser spectroscopy will occur.

Oliveira, Tiago, Pedro Matias, and Corneliu Cismasiu. "Comportamento de painéis de vidro laminado à ação de explosões - Geração de curvas Pressão-Impulso." PROTEDES2022. Região Sul da Ordem dos Engenheiros, Lisboa 2022.
Lopes, Tiago, Carmen Morgado, and Fernanda Barbosa. "Gait Monitor and Analyzer (GMA): a Wearable Sensor-based Gait Analysis System." Proceedings of International Conference on Pervasive Computing and Communications Workshops and other Affiliated Events. Italy 2022.
Cardoso, João, Patrícia Almeida, Gonçalo Catatão, Guilherme Cândida, Frederico Páscoa, Daniela Silva, Carla Machado, João P. Borges, and Alexandre Velhinho. "Designing Structural Metamaterials." 8.1 (2022): 55. Abstract
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Gonçalves, Adriana, Joana Matos, Raquel Cabrita, Inês Rodrigues, João Paulo Borges, and Paula I. P. Soares. "Development of Magnetic Nanofibrous Membranes for Localized Solid Cancer Treatment." 8.1 (2022): 119. Abstract
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Morelli, Sabrina, Antonella Piscioneri, Simona Salerno, Ricardo Matos, Paula I. P. Soares, Jorge Carvalho Silva, João Paulo Borges, and Loredana De Bartolo. "Hollow Fiber and Nanofiber Membranes in Bioartificial Organs and Tissue Engineering." Hollow Fibers and Nanofibers in Membrane Science. Jenny Stanford Publishing, 2022. 409-460. Abstract
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Matos, Ricardo JR, Paula I. P. Soares, Jorge Carvalho Silva, and João Paulo Borges. "Magnetic Bioactive Glass-Based 3D Systems for Bone Cancer Therapy and Regeneration." 8.1 (2022): 18. Abstract
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Conti, Simone, Emanuel Tschopp, Octávio Mateus, Andrea Zanoni, Pierangelo Masarati, and Giuseppe Sala. "Multibody analysis and soft tissue strength refute supersonic dinosaur tail." 12.1 (2022): 19245. Abstractconti_et_al_2022._multibody_analysis_and_soft_tissue_strength_refute_supersonic_dinosaur_tail.pdfWebsite

Sauropod dinosaurs are well known for their massive sizes and long necks and tails. Among sauropods, flagellicaudatan dinosaurs are characterized by extreme tail elongation, which has led to hypotheses regarding tail function, often compared to a whip. Here, we analyse the dynamics of motion of a 3D model of an apatosaurine flagellicaudatan tail using multibody simulation and quantify the stress-bearing capabilities of the associated soft tissues. Such an elongated and slender structure would allow achieving tip velocities in the order of 30 m/s, or 100 km/h, far slower than the speed of sound, due to the combined effect of friction of the musculature and articulations, as well as aerodynamic drag. The material properties of the skin, tendons, and ligaments also support such evidence, proving that in life, the tail would not have withstood the stresses imposed by travelling at the speed of sound, irrespective of the conjectural ‘popper’, a hypothetical soft tissue structure analogue to the terminal portion of a bullwhip able to surpass the speed of sound.

Máximo, Patrícia, Miriam Colaço, Sofia R. Pauleta, Paulo J. Costa, Uwe Pischel, Jorge A. Parola, and Nuno Basílio. "Photomodulation of ultrastable host–guest complexes in water and their application in light-controlled steroid release." Organic Chemistry Frontiers. 9.16 (2022): 4238-4249. AbstractWebsite

The cucurbit[8]uril (CB8) synthetic receptor is shown to form high-affinity host–guest complexes with dicationic dithienylethene (DTE) photoswitches in water. ITC experiments combined with computational studies suggest that the formation of the inclusion complexes is mainly driven by a combination of hydrophobic effects, ion–dipole, hydrogen- and chalcogen-bonding interactions. The binding affinities were observed to be much higher for the DTE closed isomers, reaching values in the picomolar range (up to 1011 M−1) while the open isomers display up to 10 000-fold lower affinities, setting ideal conditions for the development of robust photoswitchable host–guest complexes. The light-responsive affinity of these photoswitches toward CB8 was explored to control the encapsulation and release of nanomolar affinity steroids via competitive guest replacement.

Madeira, Ricardo MD, Tânia Vieira, Jorge C. Silva, Ivone R. Oliveira, João P. Borges, Margarida RA M. Lima, and Carmo M. Lança. "Piezoelectric Calcium Modified Barium Titanate for Bone Regeneration." 8.1 (2022): 121. Abstract
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