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2015
Ullaha, Sana, Fabio {De Matteis}, Rita Branquinho, Elvira Fortunato, Rodrigo Martins, and Ivan Davoli. "{A combination of solution synthesis {&} solution combustion synthesis for highly conducting and transparent Aluminum Zinc Oxide thin films}." 2015 IEEE 15th International Conference on Nanotechnology (IEEE-NANO). IEEE, 2015. 144-147. Abstract

Aluminum Zinc Oxide has been extensively investigated as a cheap alternative to transparent conducting tin oxide films for electronic and optoelectronic applications. Thin films of Aluminum Zinc Oxide have been developed successfully through a combination of solution combustion synthesis and solution synthesis. Zn(NO3)3·6H2O as metal source was dissolved in 2-methoxyethanol as solvent through combustion synthesis with Urea as fuel while dopant source of AlCl3·6H2O was mixed separately in solvent to avoid aluminum oxide formation in the films. Precursor solutions were obtained mixing Zn {&} Al separate solutions in 9:1, 8:2, and 7:3 ratios respectively with oxide, fuel and dopant concentrations of 0.5, 0.25, 0.1, and 0.05 M. The film stacks have been prepared through spin-coating with heating at 400°C for 10 minutes after each deposition to remove residuals and evaporate solvents. Thermal annealing in oven at 600°C for 1 hour followed by rapid thermal annealing at 500°C {&} 600°C first in vacuum and then in N2-5{%}H2 environment respectively for 10 minutes each reduced the resistivity of film stacks. Film stack with 10 layers for an average thickness of 0.5$μ$m gave the best Hall Effect resistivity of 3.2 × 10-2 $Ømega$-cm in the case of 0.5M solution with Zn:Al mixing ratio of 9:1 for RTA annealings at 600°C with an average total transparency of 80 {%} in the wavelength range of 400-1200 nm. The results show a clear trend that increasing the amount of ingredients resistivity could further be decreased.

Saponaro, A., C. Donadoni, S. R. Pauleta, F. Cantini, M. Matzapetakis, G. Thiel, L. Banci, B. Santoro, and A. Moroni. "HCN Channels: The Molecular Basis for their cAMP-TRIP8b Regulation." Biophysical Journal. Vol. 108. Biophys J, 108. 2015. 366a. Abstract
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Santos, Lidia, Daniela Nunes, Tomas Calmeiro, Rita Branquinho, Daniela Salgueiro, Pedro Barquinha, Luis Pereira, Rodrigo Martins, and Elvira Fortunato. "Solvothermal Synthesis of Gallium-Indium-Zinc-Oxide Nanoparticles for Electrolyte-Gated Transistors." Acs Applied Materials & Interfaces. 7 (2015): 638-646. AbstractWebsite
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AC, Baptista, Botas AM, Almeida AP, Nicolau AT, Falcão BP, Soares MJ, Leitão JP, Martins R, Borges JP, and Ferreira I. "Down conversion photoluminescence on PVP/Ag-nanoparticles electrospun composite fibers." Optical Materials. 39 (2015): 278-281. Abstract
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Machado, J., J. Adamczewski-Musch, A. Blanco, K. Boretzky, P. Cabanelas, L. Cartegni, Ferreira R. Marques, P. Fonte, J. Fruehauf, D. Galaviz, M. Heil, A. Henriques, G. Ickert, D. Körper, L. Lopes, M. Palka, A. Pereira, D. Rossi, H. Simon, P. Teubig, M. Traxler, P. Velho, S. Altstadt, L. Atar, T. Aumann, D. Bemmerer, C. Caesar, A. Charpy, Z. Elekes, E. Fiori, I. Gasparic, J. Gerbig, K. Göbel, T. Heftrich, M. Heine, A. Heinz, M. Holl, A. Ignatov, J. Isaak, H. Johansson, A. Kelic-Heil, C. Lederer, S. Lindberg, B. Löher, J. Marganiec, M. Martensson, T. Nilsson, V. Panin, S. Paschalis, M. Petri, R. Plag, M. Pohl, G. Rastrepina, R. Reifarth, T. P. Reinhardt, M. Röder, D. Savran, H. Scheit, P. Schrock, J. Silva, D. Stach, F. Strannerdahl, R. Thies, A. Wagner, F. Wamers, and M. Weigand. "{Performance of timing Resistive Plate Chambers with protons from 200 to 800 MeV}." Journal of Instrumentation. 10 (2015): C01043. AbstractWebsite
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Santos, Lídia, Daniela Nunes, Tomás Calmeiro, Rita Branquinho, Daniela Salgueiro, Pedro Barquinha, LuÍs Pereira, Rodrigo Martins, and Elvira Fortunato. "{Solvothermal synthesis of gallium-indium-zinc-oxide nanoparticles for electrolyte-gated transistors.}." ACS applied materials {&} interfaces. 7 (2015): 638-46. AbstractWebsite

Solution-processed field-effect transistors are strategic building blocks when considering low-cost sustainable flexible electronics. Nevertheless, some challenges (e.g., processing temperature, reliability, reproducibility in large areas, and cost effectiveness) are requirements that must be surpassed in order to achieve high-performance transistors. The present work reports electrolyte-gated transistors using as channel layer gallium-indium-zinc-oxide nanoparticles produced by solvothermal synthesis combined with a solid-state electrolyte based on aqueous dispersions of vinyl acetate stabilized with cellulose derivatives, acrylic acid ester in styrene and lithium perchlorate. The devices fabricated using this approach display a ION/IOFF up to 1 × 10(6), threshold voltage (VTh) of 0.3-1.9 V, and mobility up to 1 cm(2)/(V s), as a function of gallium-indium-zinc-oxide ink formulation and two different annealing temperatures. These results validates the usage of electrolyte-gated transistors as a viable and promising alternative for nanoparticle based semiconductor devices as the electrolyte improves the interface and promotes a more efficient step coverage of the channel layer, reducing the operating voltage when compared with conventional dielectrics gating. Moreover, it is shown that by controlling the applied gate potential, the operation mechanism of the electrolyte-gated transistors can be modified from electric double layer to electrochemical doping.

Pavan, Michele, Sven R??hle, Adam Ginsburg, David A. Keller, Hannah-Noa Noa Barad, Paolo M. Sberna, Daniela Nunes, Rodrigo Martins, Assaf Y. Anderson, Arie Zaban, Elvira Fortunato, Sven Rühle, Adam Ginsburg, David A. Keller, Hannah-Noa Noa Barad, Paolo M. Sberna, Daniela Nunes, Rodrigo Martins, Assaf Y. Anderson, Arie Zaban, and Elvira Fortunato. "{TiO2/Cu2O all-oxide heterojunction solar cells produced by spray pyrolysis}." Solar Energy Materials and Solar Cells. 132 (2015): 549-556. AbstractWebsite

Here we present for the first time a TiO2/Cu2O all-oxide heterojunction solar cell entirely produced by spray pyrolysis onto fluorine doped tin oxide (FTO) covered glass substrates, using silver as a back contact. A combinatorial approach was chosen to investigate the impact of the TiO2 window layer and the Cu2O light absorber thicknesses. We observe an open circuit voltage up to 350 mV and a short circuit current density which is strongly dependent of the Cu2O thickness, reaching a maximum of {\~{}}0.4 mA/cm2. Optical investigation reveals that a thickness of 300 nm spray pyrolysis deposited Cu2O is sufficient to absorb most photons with an energy above the symmetry allowed optical transition of 2.5 eV, indicating that the low current densities are caused by strong recombination in the absorber that consists of small Cu2O grains.

Nunes, Daniela, Lidia Santos, Paulo Duarte, Ana Pimentel, Joana V. Pinto, Pedro Barquinha, Patricia A. Carvalho, Elvira Fortunato, and Rodrigo Martins. "Room Temperature Synthesis of Cu2O Nanospheres: Optical Properties and Thermal Behavior." Microscopy and Microanalysis. 21 (2015): 108-119. AbstractWebsite
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Branquinho, Rita, Daniela Salgueiro, Ana Santa, Asal Kiazadeh, Pedro Barquinha, Luis Pereira, Rodrigo Martins, and Elvira Fortunato. "Towards environmental friendly solution-based ZTO/AlOx TFTs." Semiconductor Science and Technology. 30 (2015). AbstractWebsite
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Blanco, A., J. Adamczewski-Musch, K. Boretzky, P. Cabanelas, L. Cartegni, Ferreira R. Marques, P. Fonte, J. Fruehauf, D. Galaviz, M. Heil, A. Henriques, G. Ickert, D. Körper, L. Lopes, M. Palka, A. Pereira, D. Rossi, H. Simon, P. Teubig, M. Traxler, P. Velho, S. Altstadt, L. Atar, T. Aumann, D. Bemmerer, C. Caesar, A. Charpy, Z. Elekes, E. Fiori, I. Gasparic, J. Gerbig, K. Göbel, T. Heftrich, M. Heine, A. Heinz, M. Holl, A. Ignatov, J. Isaak, H. Johansson, A. Kelic-Heil, C. Lederer, S. Lindberg, B. Löher, J. Machado, J. Marganiec, M. Martensson, T. Nilsson, V. Panin, S. Paschalis, M. Petri, R. Plag, M. Pohl, G. Rastrepina, R. Reifarth, T. P. Reinhardt, M. Röder, D. Savran, H. Scheit, P. Schrock, J. Silva, D. Stach, F. Strannerdahl, R. Thies, A. Wagner, F. Wamers, and M. Weigand. "{Performance of timing resistive plate chambers with relativistic neutrons from 300 to 1500 MeV}." Journal of Instrumentation. 10 (2015): C02034. AbstractWebsite
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Benis, E. P., S. Doukas, T. J. M. Zouros, P. Indelicato, F. Parente, C. Martins, J. P. Santos, and J. P. Marques. "Evaluation of the effective solid angle of a hemispherical deflector analyser with injection lens for metastable Auger projectile states." Nuclear Inst. and Methods in Physics Research, B. 365 (2015): 457-461. AbstractWebsite

Nuclear Inst. and Methods in Physics Research, B, 365 (2015) 457-461. doi:10.1016/j.nimb.2015.07.006

Morais, Ana Rita C., Joana Vaz Pinto, Daniela Nunes, Luísa B. Roseiro, Maria Conceição Oliveira, Elvira Fortunato, and Rafał Bogel-Łukasik. "{Imidazole: Prospect Solvent for Lignocellulosic Biomass Fractionation and Delignification}." ACS Sustainable Chemistry {&} Engineering (2015). AbstractWebsite
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Guerra, M., J. M. Sampaio, T. I. Madeira, F. Parente, P. Indelicato, J. P. Marques, J. P. Santos, J. Hoszowska, Cl J. Dousse, L. Loperetti, F. Zeeshan, M. Muller, R. Unterumsberger, and B. Beckhoff. "Theoretical and experimental determination of L-shell decay rates, line widths, and fluorescence yields in Ge." Physical Review A. 92 (2015): 022507-9. AbstractWebsite
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Guerra, M., S. C. Pé-Leve Santos, A. M. E. Barroso, C. P. S. Fonseca, M. Eloy Cruz, P. Amaro, J. L. Figueirinhas, M. L. Carvalho, and J. P. Santos. "Spatially resolved determination of toxic trace elements in plants of Panasqueira mining region using micro X-ray fluorescence." Microscopy and Microanalysis. 21 (2015): 54-55. AbstractWebsite
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Monteiro-Henriques, T., M. J. Martins, J. O. Cerdeira, P. Silva, P. Arsénio, Á. Silva, A. Bellu, and J. C. Costa. "Bioclimatological mapping tackling uncertainty propagation: application to mainland Portugal." International Journal of Climatology. 36 (2015): 400-411. AbstractWebsite
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Tschopp, Emanuel, Octávio Mateus, and Roger B. J. Benson. "A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda)." PeerJ. 3 (2015): e857. Abstracttschopp_et_al_2015_brontosaurus_peerj-857.pdfWebsite

Diplodocidae are among the best known sauropod dinosaurs. Several species were described in the late 1800s or early 1900s from the Morrison Formation of North America. Since then, numerous additional specimens were recovered in the USA, Tanzania, Portugal, and Argentina, as well as possibly Spain, England, Georgia, Zimbabwe, and Asia. To date, the clade includes about 12 to 15 nominal species, some of them with questionable taxonomic status (e.g., ‘\textit{Diplodocus}’ \textit{hayi} or \textit{Dyslocosaurus polyonychius}), and ranging in age from Late Jurassic to Early Cretaceous. However, intrageneric relationships of the iconic, multi-species genera \textit{Apatosaurus} and \textit{Diplodocus} are still poorly known. The way to resolve this issue is a specimen-based phylogenetic analysis, which has been previously implemented for \textit{Apatosaurus}, but is here performed for the first time for the entire clade of Diplodocidae.The analysis includes 81 operational taxonomic units, 49 of which belong to Diplodocidae. The set of OTUs includes all name-bearing type specimens previously proposed to belong to Diplodocidae, alongside a set of relatively complete referred specimens, which increase the amount of anatomically overlapping material. Non-diplodocid outgroups were selected to test the affinities of potential diplodocid specimens that have subsequently been suggested to belong outside the clade. The specimens were scored for 477 morphological characters, representing one of the most extensive phylogenetic analyses of sauropod dinosaurs. Character states were figured and tables given in the case of numerical characters.The resulting cladogram recovers the classical arrangement of diplodocid relationships. Two numerical approaches were used to increase reproducibility in our taxonomic delimitation of species and genera. This resulted in the proposal that some species previously included in well-known genera like \textit{Apatosaurus} and \textit{Diplodocus} are generically distinct. Of particular note is that the famous genus \textit{Brontosaurus} is considered valid by our quantitative approach. Furthermore, “\textit{Diplodocus}” hayi represents a unique genus, which will herein be called \textit{Galeamopus} gen. nov. On the other hand, these numerical approaches imply synonymization of “\textit{Dinheirosaurus}” from the Late Jurassic of Portugal with the Morrison Formation genus \textit{Supersaurus}. Our use of a specimen-, rather than species-based approach increases knowledge of intraspecific and intrageneric variation in diplodocids, and the study demonstrates how specimen-based phylogenetic analysis is a valuable tool in sauropod taxonomy, and potentially in paleontology and taxonomy as a whole.

Biscaia, Hugo C., Carlos Chastre, and André Viegas. "A new discrete method to model unidirectional FRP-to-parent material bonded joints subjected to mechanical loads." Composite Structures. 121 (2015): 280-295. AbstractWebsite

Nowadays fiber reinforced polymer (FRP) composites play an important role in the strengthening of structures. Different methods can be used to apply these materials: the externally bonded reinforcement (EBR), and the near surface mounted (NSM) using strips and NSM rods. There are only a few studies comparing these methods or presenting an efficient model to simulate these strengthening techniques. This study looks mainly at the analysis of the interface between FRP-to-parent material bonded joints. The paper examines, through a new discrete model based on axial and shear springs, the performance of FRP-to-parent material bonded joints for EBR or NSM techniques using strips or composite rods. In order to implement the model a routine in MATLAB was developed and several bond–slip curves were assumed. The results revealed that load–slip curves or bond stresses, strains or slippages along the bonded length obtained from several bond–slip curves are similar to the analytical and other numerical solutions found in literature. In what concerns the adhesion between two different materials, and assuming the same bond characteristics for the three fiber strengthening techniques, the NSM system using FRP strips had the highest maximum load transmitted to the FRP strip combined with the lowest effective bond length. The results obtained from the proposed model were also very accurate with that obtained from an analytical solution found in literature that simulates the debonding phenomenon of FRP-to-concrete interfaces between to adjacent cracks.

Ameller, David, Xavier Franch, Cristina Gómez, João Araújo, Richard Berntsson Svensson, Stefan Biffl, Jordi Cabot, Vittorio Cortellessa, Maya Daneva, Daniel Mendez Fernández, Ana Moreira, Henry Muccini, Antonio Vallecillo, Manuel Wimmer, Vasco Amaral, Hugo Brunelière, Loli Burgueño, Miguel Goulão, Bernhard Schätz, and Sabine Teufl. "Handling Non-Functional Requirements in Model-Driven Development: An Ongoing Industrial Survey." 23rd International Conference on Requirements Engineering (RE'15) - RE: Next! Ottawa, Canada: IEEE Computer Society, 2015.
Baltazar, Luis G., Fernando MA Henriques, and Maria Teresa Cidade. "Contribution to the design of hydraulic lime-based grouts for masonry consolidation." 21.6 (2015): 698-709. Abstract
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Brehm, Tiago, Gonçalo Pereira, C. R. Leal, Clara Gonçalves, João P. Borges, and Maria Teresa Cidade. "Electrorheological characterization of dispersions in silicone oil of encapsulated liquid crystal 4-n-penthyl-4′-cyanobiphenyl in polyvinyl alcohol and in silica." 90.3 (2015): 035802. Abstract
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Baltazar, Luis G., Fernando MA Henriques, and Maria Teresa Cidade. "Experimental Study and Modeling of Rheological and Mechanical Properties of NHL Grouts." 27.12 (2015): 04015055. Abstract
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Ghisolfi, A., F. Condello, C. Fliedel, V. Rosa, and P. Braunstein. "Facile and Room-Temperature Activation of Csp3-Cl Bonds by Cheap and Air-Stable Nickel(II) Complexes of (N-Thioether) DPPA-Type Ligands." Organometallics. 34.11 (2015): 2255-2260. AbstractWebsite
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Gomes, Ivette M., Fátima M. Brilhante, Frederico Caeiro, and Dinis Pestana. "A new partially reduced-bias mean-of-order p class of extreme value index estimators." Computational Statistics & Data AnalysisComputational Statistics & Data Analysis. 82 (2015): 223-227. AbstractWebsite

A class of partially reduced-bias estimators of a positive extreme value index (EVI), related to a mean-of-order-p class of EVI-estimators, is introduced and studied both asymptotically and for finite samples through a Monte-Carlo simulation study. A comparison between this class and a representative class of minimum-variance reduced-bias (MVRB) EVI-estimators is further considered. The MVRB EVI-estimators are related to a direct removal of the dominant component of the bias of a classical estimator of a positive EVI, the Hill estimator, attaining as well minimal asymptotic variance. Heuristic choices for the tuning parameters p and k, the number of top order statistics used in the estimation, are put forward, and applied to simulated and real data.A class of partially reduced-bias estimators of a positive extreme value index (EVI), related to a mean-of-order-p class of EVI-estimators, is introduced and studied both asymptotically and for finite samples through a Monte-Carlo simulation study. A comparison between this class and a representative class of minimum-variance reduced-bias (MVRB) EVI-estimators is further considered. The MVRB EVI-estimators are related to a direct removal of the dominant component of the bias of a classical estimator of a positive EVI, the Hill estimator, attaining as well minimal asymptotic variance. Heuristic choices for the tuning parameters p and k, the number of top order statistics used in the estimation, are put forward, and applied to simulated and real data.

Brusatte, Stephen L., Richard J. Butler, Octávio Mateus, and Sébastien J. Steyer. "A new species of Metoposaurus from the Late Triassic of Portugal and comments on the systematics and biogeography of metoposaurid temnospondyls." Journal of Vertebrate PaleontologyJournal of Vertebrate Paleontology (2015): e912988. Abstractbrusatte_et_al2015metoposaurusportugal.pdfWebsite

ABSTRACTMetoposaurids are a group of temnospondyl amphibians that filled crocodile-like predatory niches in fluvial and lacustrine environments during the Late Triassic. Metoposaurids are common in the Upper Triassic sediments of North Africa, Europe, India, and North America, but many questions about their systematics and phylogeny remain unresolved. We here erect Metoposaurus algarvensis, sp. nov., the first Metoposaurus species from the Iberian Peninsula, based on several new specimens from a Late Triassic bonebed in Algarve, southern Portugal. We describe the cranial and pectoral anatomy of M. algarvensis and compare it with other metoposaurids (particularly other specimens of Metoposaurus from Germany and Poland). We provide a revised diagnosis and species-level taxonomy for the genus Metoposaurus, which is currently represented with certainty by three European species (M. diagnosticus, M. krasiejowensis, M. algarvensis). We also identify cranial characters that differentiate these three species, and may have phylogenetic significance. These include features of the braincase and mandible, which indicate that metoposaurid skulls are more variable than previously thought. The new Portuguese bonebed provides further evidence that metoposaurids congregated in fluvial and lacustrine settings across their geographic range and often succumbed to mass death events. We provide an updated paleogeographic map depicting all known metoposaurid occurrences, which shows that these temnospondyls were globally distributed in low latitudes during the Late Triassic and had a similar, but not identical, paleogeographic range as phytosaurs.http://zoobank.org/urn:lsid:zoobank.org:pub:083C80C6-0AB6-49E1-A636-6A8BDBC06A47ABSTRACTMetoposaurids are a group of temnospondyl amphibians that filled crocodile-like predatory niches in fluvial and lacustrine environments during the Late Triassic. Metoposaurids are common in the Upper Triassic sediments of North Africa, Europe, India, and North America, but many questions about their systematics and phylogeny remain unresolved. We here erect Metoposaurus algarvensis, sp. nov., the first Metoposaurus species from the Iberian Peninsula, based on several new specimens from a Late Triassic bonebed in Algarve, southern Portugal. We describe the cranial and pectoral anatomy of M. algarvensis and compare it with other metoposaurids (particularly other specimens of Metoposaurus from Germany and Poland). We provide a revised diagnosis and species-level taxonomy for the genus Metoposaurus, which is currently represented with certainty by three European species (M. diagnosticus, M. krasiejowensis, M. algarvensis). We also identify cranial characters that differentiate these three species, and may have phylogenetic significance. These include features of the braincase and mandible, which indicate that metoposaurid skulls are more variable than previously thought. The new Portuguese bonebed provides further evidence that metoposaurids congregated in fluvial and lacustrine settings across their geographic range and often succumbed to mass death events. We provide an updated paleogeographic map depicting all known metoposaurid occurrences, which shows that these temnospondyls were globally distributed in low latitudes during the Late Triassic and had a similar, but not identical, paleogeographic range as phytosaurs.http://zoobank.org/urn:lsid:zoobank.org:pub:083C80C6-0AB6-49E1-A636-6A8BDBC06A47