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2014
Borges, J. P., JP Canejo, S. N. Fernandes, P. Brogueira, and M. H. Godinho. "Cellulose‐Based Liquid Crystalline Composite Systems." Nanocellulose Polymer Nanocomposites: Fundamentals and Applications (2014): 215-235. Abstract
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Xavier, J., J. C. R. Pereira, and A. M. P. de Jesus. "Characterisation of steel components under monotonic loading by means of image-based methods." Optics and Lasers in Engineering. 53 (2014): 142-151. AbstractWebsite
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Contreras, Javier, Rodrigo Martins, Pawel Wojcik, Sergej Filonovich, Hugo Aguas, Luis Gomes, Elvira Fortunato, and Isabel Ferreira. "Color sensing ability of an amorphous silicon position sensitive detector array system." Sensors and Actuators A: Physical. 205 (2014): 26-37. Abstract
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b b b b d b b Contreras, J.a b, Martins Wojcik Filonovich Aguas Gomes Fortunato Ferreira R. a P. a. "Color sensing ability of an amorphous silicon position sensitive detector array system." Sensors and Actuators, A: Physical. 205 (2014): 26-37. AbstractWebsite

The color sensing ability of a data acquisition prototype system integrating a 32 linear array of 1D amorphous silicon position sensitive detectors (PSD) was analyzed. Besides being used to reproduce a 3D profile of highly reflective surfaces, here we show that it can also differentiate primary red, green, blue (RGB) and derived colors. This was realized by using an incident beam with a RGB color combination and adequate integration times taking into account that a color surface mostly reflects its corresponding color. A mean colorimetric error of 25.7 was obtained. Overall, we show that color detection is possible via the use of this sensor array system, composed by a simpler amorphous silicon pin junction. © 2013 Elsevier B.V. All rights reserved.

Contreras, Javier, Rodrigo Martins, Pawel Wojcik, Sergej Filonovich, Hugo Aguas, Luis Gomes, Elvira Fortunato, and Isabel Ferreira. "Color sensing ability of an amorphous silicon position sensitive detector array system." Sensors and Actuators A: Physical. 205 (2014): 26-37. Abstract
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Teixeira, RT, AM Fortes, C. Pinheiro, and H. Pereira. "Comparison of good- and bad-quality cork: application of high-throughput sequencing of phellogenic tissue." Journal of Experimental Botany (2014). Abstract
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Teixeira, RT, AM Fortes, C. Pinheiro, and H. Pereira. "Comparison of good- and bad-quality cork: application of high-throughput sequencing of phellogenic tissue." Journal of Experimental Botany (2014). Abstract
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Mateus, Octávio. "Comparison of modern and fossil Crocodylomorpha eggs and contribution to the oophylogeny of Amniota." Annual Meeting of the European Association of Vertebrate Palaeontologists. , p. 192, Regione Piemonte: European Association of Vertebrate Palaeontologists. Museo Regionale di Scienze Naturali. 2014. Abstract
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Conchinha, Cristina, João Vilhete Viegas D’Abreu, and João Correia de Freitas. "A comunidade {Robots} : a {Robótica} {Educativa}, um {Ambiente} {Inclusivo}." Atas da {III} {Cingresso} {Internacional} {TIC} em {Educação}. Lisboa 2014. 1581-1585. Abstract
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Dias, C. J., and L. N. Goncalves. "The concept of negative mass and its application to Helium-balloon-type dynamics." American Journal of Physics. 82 (2014): 997-1000. AbstractWebsite
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Araújo, João, Janusz Konieczny, and António Malheiro. "Conjugation in semigroups." J. Algebra. 403 (2014): 93-134. AbstractWebsite
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Amaral, Paula, Immanuel M. Bomze, and Joaquim Júdice. "Copositivity and constrained fractional quadratic problems." Mathematical Programming. 146 (2014): 325-350. Abstract
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Russo, J., O. Mateus, A. Balbino, and M. Marzola. "Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal." Comunica\\c cões Geológicas. 101, Especial I (2014): 563-566. Abstract
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Russo, J., O. Mateus, A. Balbino, and M. Marzola. "Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal." Comunica\\c cões Geológicas. 101, Especial I (2014): 563-566. Abstract
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Russo, J., O. Mateus, A. Balbino, and M. Marzola. "Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal." Comunica\\c cões Geológicas. 101, Especial I (2014): 563-566. Abstract

We here present fossil Crocodylomorpha eggshells from the Upper Jurassic Lourinhã Formation of Portugal, recovered from five sites: one nest from Cambelas with 13 eggs, and three partial eggs and various fragments from, Paimogo N (I), Paimogo S (II), Casal da Rola, and Peralta. All specimens but the nest were found in association with dinosaur egg material. Our research reveals that on a micro- and ultrastructural analysis, all samples present the typical characters consistent with crocodiloid eggshell morphotype, such as the shell unit shape, the organization of the eggshell layers, and the triangular blocky extinction observed with crossed nicols. We assign the material from the Lourinhã Formation to the oofamily Krokolithidae, making it the oldest crocodylomorph eggs known so far, as well as the best record for eggs of non- crocodylian crocodylomorphs. Furthermore, our study indicates that the basic structure of crocodiloid eggshells has remained stable since at least the Upper Jurassic.

Soares, R. S. a, R. C. C. a Monteiro, A. A. S. a Lopes, M. M. R. A. a Lima, B. A. b Sava, and M. b Elisa. "Crystallization and microstructure of Eu3 +-doped lithium aluminophosphate glass." Journal of Non-Crystalline Solids. 403 (2014): 9-17. AbstractWebsite

A transparent Eu3 +-doped lithium aluminophosphate glass was prepared by melt-quenching technique. The thermal behavior of the glass was investigated by differential thermal analysis (DTA), the structure was studied by X-ray diffraction (XRD) and the morphology was observed by optical polarization microscopy and scanning electron microscopy (SEM). The activation energy of glass transition and the activation energy of crystallization and Avrami exponent have been evaluated under non-isothermal conditions from the data obtained by DTA at different heating rates. DTA curves exhibited an endothermic peak associated with the glass transition and two exothermic peaks. The mean value calculated for the activation energy of glass transition was 545 kJ mol- 1. The activation energy of crystallization was   400 kJ mol- 1 for the first exothermic peak and   170 kJ mol- 1 for the second peak. The Avrami exponent was   1 for both peaks indicating surface crystallization. XRD results showed that the main crystalline phase, aluminum metaphosphate, Al(PO3)3, and aluminum phosphate, AlPO4, were formed together with lithium barium phosphate, Li 3Ba(PO3)7, during the first exothermic peak and together with barium pyrophosphate, Ba2P2O7, during the second peak. Morphological study of heat-treated glass samples revealed microstructural features that confirmed a surface crystallization process. © 2014 Elsevier B.V.

Lopes, A. A. S. a, R. C. C. a Monteiro, R. S. a Soares, M. M. R. A. a Lima, and M. H. V. b Fernandes. "Crystallization kinetics of a barium-zinc borosilicate glass by a non-isothermal method." Journal of Alloys and Compounds. 591 (2014): 268-274. AbstractWebsite

The crystallization kinetics of a glass with a molar composition 40BaO-20ZnO-30B2O3-10SiO2 was investigated. The kinetic parameters, activation energy for crystallization (Ec) and Avrami exponent (n), were evaluated under non-isothermal conditions using the results obtained by differential thermal analysis (DTA) performed at different heating rates. DTA curves exhibited two overlapping exothermic peaks associated with the crystallization of the glass. Barium borate (BaB4O 7) was the first crystalline phase to be formed and it was followed by the formation of barium zinc silicate (BaZnSiO4), as identified by XRD. For the first exothermic peak, when the fraction of crystallization (χ) increased from 0.1 to 0.9, the local activation energy (E c(χ)) decreased from 700 to 500 kJ/mol, while for the second exothermic peak, Ec(χ) slightly increased from 490 to 570 kJ/mol. For the range of 0.1 < χ < 0.9, the local Avrami exponent (n(χ)) increased from ∼1 to 1.4 for the first exothermic peak and it decreased from ∼1.7 to 1.4 for the second exothermic peak. Observation by SEM of the microstructure of sintered glass samples revealed that crystallization started at the surface of glass particles, with growth of lamellar crystallites, that together with some quasi-spherical nano-sized crystallites progressed towards the inside of the glass at the highest sintering temperatures. The change of the local activation energy with the fraction of crystallization suggested that a multi-step kinetic reaction took place during sintering and crystallization of the glass. © 2013 Elsevier B.V. All rights reserved.

Soares, R. S., R. C. C. Monteiro, M. M. R. A. Lima, and R. J. C. Silva. "Crystallization of lithium disilicate-based multicomponent glasses - Effect of silica/lithia ratio." Ceramics International. 41 (2014): 317-324. AbstractWebsite

Two glass compositions were prepared from the system SiO2-Li2O-K2O-ZrO2-P2O5 with different SiO2/Li2O ratio (2.39 and 3.39) and the crystallization behavior was investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The crystallization kinetic parameters (activation energy of crystallization and Avrami exponent) were evaluated by different methods from the data obtained by DTA performed at different heating rates. For both glasses, two exothermic peaks were observed in the DTA curves, and the crystallization peak temperatures increased with SiO2/Li2O ratio. XRD analysis revealed that the first peak corresponds to the crystallization of lithium metasilicate (Li2SiO3) and the second to the formation of lithium disilicate (Li2Si2O5). After heating the glasses at a temperature above the second crystallization peak (900 °C), both Li2Si2O5 and Li2SiO3 were found in samples having the lowest SiO2/Li2O ratio, whereas no Li2SiO3 was detected in samples with the highest SiO2/Li2O ratio. For both glasses, the value obtained by different methods for the activation energy of crystallization was in the range of 225-275 kJ mol-1 for the first exothermic peak and in the range of 425-500 kJ mol-1 for the second peak. The estimated Avrami exponent was close to 1 for the first exothermic peak, indicating surface crystallization, and close to 3 for the second exothermic peak, suggesting volume crystallization. This was confirmed by the morphological study made by SEM that showed needle-like crystals in the microstructure of samples with lithium metasilicate and granular crystals in the microstructure of samples having lithium disilicate. © 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Hendrickx, Christophe, Octávio Mateus, and Ricardo Araújo. "The dentition of Megalosauridae (Theropoda: Dinosauria)." {APP} (2014). AbstractWebsite
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Xavier, J., M. Oliveira, J. J. L. Morais, and M. F. S. F. de Moura. "Determining mode İI\} cohesive law of Pinus pinaster by combining the end-notched flexure test with digital image correlation." Construction and Building Materials. 71 (2014): 109-115. Abstract

Abstract This work addresses the direct identification of cohesive law of Pinus pinaster in mode II. The end-notched flexure (ENF) test is selected for mode İI\} loading. The strain energy release rate in mode İI\} (GII) is determined according to the compliance-based beam method (CBBM) by processing the global load�displacement curve, without requirements to monitor the crack length during test. The fracture test is coupled with digital image correlation (DIC) for the local measurement of the crack tip opening displacement in mode İI\} (wII). Using a direct method, the cohesive law in mode İI\} (sII�wII) is determined by differentiating the GII�wII relationship. The procedure is validated from both numerical, using finite element analyses including cohesive zone modelling, and experimental approaches. The methodology and accuracy on this reconstruction is discussed. It is concluded that the proposed data reduction scheme is suitable for assessing the cohesive law of P. pinaster in mode II.

Subramani, P., S. Rana, D. V. Oliveira, R. Fangueiro, and J. Xavier. "Development of novel auxetic structures based on braided composites." Materials & Design. 61 (2014): 286-295. AbstractWebsite
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Mateus, Octávio. "Dinosaur taphonomy in the Lourinhã Formation (Late Jurassic, Portugal)." International Meeting on Taphonomy and Fossilization. 2014. 60-61. Abstract
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Xavier, J., M. Oliveira, P. Monteiro, J. J. L. Morais, and M. F. S. F. Moura. "Direct Evaluation of Cohesive Law in Mode I of Pinus pinaster by Digital Image Correlation." Experimental Mechanics. 54 (2014): 829-840. AbstractWebsite
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