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2017
Silva, M. A. G., H. C. Biscaia, and C. Chastre. "Aging of some GFRP-concrete joints under external pressure." AIS2017 - 6th Asia-Pacific Conference on FRP in Structures. Singapore 2017. Abstract

Compressive stresses created by lateral external pressure on laminates are an important factor on success of the use of mechanical anchorage of externally bonded reinforcement (EBR). A program of double shear tests with imposed normal stresses on GFRP plates bonded to a concrete surface and a bond-slip model are described. Results generated numerically are summarized and used as reference values against those obtained after accelerated aging by freeze-thaw cycles, and temperature cycles of the same amplitude but range closer to the glass vitreous temperature. Numerical modelling showed that the bonded length is fully stressed prior to failure. Increasing lateral pressure led to a larger maximum bond stress and strength at the interface. Cohesion, fracture energy and internal friction angle changes are calculated and used to analyze the effects of the aforementioned cycles on the expected behaviour of the GFRP-concrete joints, namely at the interface.

Guerra, M., P. Amaro, J. P. Santos, and P. Indelicato. "Relativistic calculations of screening parameters and atomic radii of neutral atoms." Atomic Data and Nuclear Data Tables. 117-118 (2017): 439-457. AbstractWebsite

Atomic Data and Nuclear Data Tables, 117-118 (2017) 439-457. doi:10.1016/j.adt.2017.01.001

Pessanha, Sofia, Ana Samouco, Ricardo Adão, Maria Luisa Carvalho, Jose Paulo Santos, and Pedro Amaro. "Detection limits evaluation of a portable energy dispersive X-ray fluorescence setup using different filter combinations." X-Ray Spectrometry. 46 (2017): 102-106. AbstractWebsite

In this paper, we study the performance of a portable energy dispersive X‐ray fluorescence spectrometer by making use of different filter configurations at the X‐ray tube output. To fulfill this purpose,...

Socratous, Josephine, Shun Watanabe, Kulbinder K. Banger, Christopher N. Warwick, Rita Branquinho, Pedro Barquinha, Rodrigo Martins, Elvira Fortunato, and Henning Sirringhaus. "{Energy-dependent relaxation time in quaternary amorphous oxide semiconductors probed by gated Hall effect measurements}." Physical Review B. 95 (2017): 045208. AbstractWebsite

Despite the success of exploiting the properties of amorphous oxide semiconductors for device applications, the charge transport in these materials is still not clearly understood. The observation of a definite Hall voltage suggests that electron transport in the conduction band is free-electron-like. However, the temperature dependence of the Hall and field-effect mobilities cannot be explained using a simple bandlike model. Here, we perform gated Hall effect measurements in field-effect transistors, which allow us to make two independent estimates of the charge carrier concentration and determine the Hall factor providing information on the energy dependence of the relaxation time. We demonstrate that the Hall factor in a range of sputtered and solution-processed quaternary amorphous oxides, such as a-InGaZnO, is close to two, while in ternary oxides, such as InZnO, it is near unity. This suggests that quaternary elements like Ga act as strong ionized impurity scattering centers in these materials.

Silva, A. L. M., S. Cirino, M. L. Carvalho, M. Manso, S. Pessanha, C. D. R. Azevedo, L. F. N. D. Carramate, J. P. Santos, M. Guerra, and J. F. C. A. Veloso. "Elemental mapping in a contemporary miniature by full-field X-ray fluorescence imaging with gaseous detector vs. scanning X-ray fluorescence imaging with polycapillary optics." (2017): 1-7. Abstract

Spectrochimica Acta Part B: Atomic Spectroscopy, 129 (2016) 1-7. doi:10.1016/j.sab.2016.12.006

Chiari, M., E. Alves, Bogdanović I. Radović, J. Cruz, L. Csedreki, M. Fonseca, D. Galaviz, A. Henriques, M. Jak{\v s}ić, A. P. Jesus, O. Kakuee, Á. Z. Kiss, A. Lagoyannis, F. Louren{\c c}o, H. Lu{\'ıs, J. Machado, B. Melon, C. K. Nuviadenu, L. Salvestrini, N. Sharifzadeh, Z. Siketić, G. Á. Sz{\'ıki, Z. Szikszai, P. Teubig, P. Velho, I. Zamboni, and M. Zarza. "{Measurement of proton induced $\gamma$-ray emission cross sections on Na from 1.0 to 4.1 MeV}." Nuclear Inst. and Methods in Physics Research, B (2017): 1-11. AbstractWebsite
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Vicente, António T., Andreia Araújo, Diana Gaspar, Lídia Santos, Ana C. Marques, Manuel J. Mendes, LuÍs Pereira, Elvira Fortunato, and Rodrigo Martins. "{Optoelectronics and Bio Devices on Paper Powered by Solar Cells}." Nanostructured Solar Cells. InTech, 2017. Abstract

The employment of printing techniques as cost-effective methods to fabricate low cost, flexible, disposable and sustainable solar cells is intimately dependent on the substrate properties and the adequate electronic devices to be powered by them. Among such devices, there is currently a growing interest in the development of user-oriented and multipurpose systems for intelligent packaging or on-site medical diagnostics, which would greatly benefit from printable solar cells as their energy source for autonomous operation. This chapter first describes and analyzes different types of cellulose-based substrates for flexible and cost effective optoelectronic and bio devices to be powered by printed solar cells. Cellulose is one of the most promising platforms for green recyclable electronics and it is fully compatible with large-scale printing techniques, although some critical requirements must be addressed. Paper substrates exist in many forms. From common office paper, to packaging cardboard used in the food industry, or nanoscale engineered cellulose (e.g. bacterial cellulose). However, it is the structure and content of paper that determines its end use. Secondly, proof-of-concept of optoelectronic and bio devices pro-duced by inkjet printing are described and show the usefulness of solar cells as a power source or as a chemical reaction initiator for sensors.

Salgueiro, Daniela, Asal Kiazadeh, Rita Branquinho, Lídia Santos, Pedro Barquinha, Rodrigo Martins, and Elvira Fortunato. "{Solution based zinc tin oxide TFTs: the dual role of the organic solvent}." Journal of Physics D: Applied Physics. 50 (2017): 065106. AbstractWebsite

Chemical solution deposition is a low cost, scalable and high performance technique to obtain metal oxide thin films. Recently, solution combustion synthesis has been introduced as a chemical route to reduce the processing temperature. This synthesis method takes advantage of the chemistry of the precursors as a source of energy for localized heating. According to the combustion chemistry some organic solvents can have a dual role in the reaction, acting both as solvent and fuel. In this work, we studied the role of 2-methoxyethanol in solution based synthesis of ZTO thin films and its influence on the performance of ZTO TFTs. The thermal behaviour of ZTO precursor solutions confirmed that 2-methoxyethanol acts simultaneously as a solvent and fuel, replacing the fuel function of urea. The electrical characterization of the solution based ZTO TFTs showed a slightly better performance and lower variability under positive gate bias stress when urea was not used as fuel, confirming that the excess fuel contributes negatively to the device operation and stability. Solution based ZTO TFTs demonstrated a low hysteresis ($Δ$V = −0.3 V) and a saturation mobility of 4–5 cm2 V−1 s−1.

Sallem, A., P. Pereira, and M. Fakhfakh. "Automatic sensitivity analysis tool for analog active filter." 2017 24th IEEE International Conference on Electronics, Circuits and Systems (ICECS). 2017. 124-127. Abstract

In this paper we deal with analog active filter design using discrete components taking into consideration tolerance effects. Sensitivity analysis is performed to determine the most influential components in the considered circuit, thus relative higher precision is offered to those parameters. Further, an in-loop optimization technique is considered, thus actual IC models are handled. An application example is presented. HSpice simulation results, supported by Monte Carlo analysis, are given to highlight efficiency of the proposed selection technique.

Amaro, Pedro, Jose Paulo Santos, Ana Samouco, Ricardo Adão, Luís Souto Martins, Sebastian Weber, Stanislav Tashenov, Maria Luisa Carvalho, and Sofia Pessanha. "Validation of the Geant4 Monte Carlo package for X-ray fluorescence spectroscopy in triaxial geometry." Spectrochimica Acta Part B: Atomic Spectroscopy. 130 (2017): 60-66. AbstractWebsite

Spectrochimica Acta Part B: Atomic Spectroscopy, 130 (2017) 60-66. doi:10.1016/j.sab.2017.02.012

Mateus, Octávio, Marco Marzola, Anne S. Schulp, Louis L. Jacobs, Michael J. Polcyn, Vladimir Pervov, António Ol{\'ı}mpio Gonçalves, and Maria Luisa Morais. "Angolan ichnosite in a diamond mine shows the presence of a large terrestrial mammaliamorph, a crocodylomorph, and sauropod dinosaurs in the Early Cretaceous of Africa." Palaeogeography, Palaeoclimatology, Palaeoecology. 471 (2017): 220-232. AbstractWebsite
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Garde, Francois, Daniel Aelenei, Laura Aelenei, Alessandra Scognamiglio, and Josef Ayoub Solution Sets for Net-Zero Energy Buildings. Wiley-{VCH} Verlag {GmbH} {&} Co. {KGaA}, 2017. AbstractWebsite
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Joaquim, Ana, Corneliu Cismasiu, Filipe Santos, and Elsa Caetano. "Estimation of the tensile force in the stay-cables of Salgueiro Maia Bridge using ambient vibration tests." ISDAC2017 - International Symposium on the Dynamics and Aerodynamics of Cables. Porto: FEUP, 2017. artigo_isdac_v5_ec.pdf
Pereira, Rui, Marco Couto, Francisco Ribeiro, Rui Rua, Jácome Cunha, João P. Fernandes, and João Saraiva. "Energy Efficiency across Programming Languages: How Do Energy, Time, and Memory Relate?" 10th ACM SIGPLAN International Conference on Software Language Engineering (SLE’17). Vancouver, Canada: ACM, 2017. paper.pdf
Bule, Pedro, Victor D. Alves, Vered Israeli-Ruimy, Ana L. Carvalho, Luís M. A. Ferreira, Steven P. Smith, Harry J. Gilbert, Shabir Najmudin, Edward A. Bayer, and Carlos M. G. A. Fontes. "Assembly of Ruminococcus flavefaciens cellulosome revealed by structures of two cohesin-dockerin complexes." Scientific Reports. 7.1 (2017): 759. AbstractWebsite

Cellulosomes are sophisticated multi-enzymatic nanomachines produced by anaerobes to effectively deconstruct plant structural carbohydrates. Cellulosome assembly involves the binding of enzyme-borne dockerins (Doc) to repeated cohesin (Coh) modules located in a non-catalytic scaffoldin. Docs appended to cellulosomal enzymes generally present two similar Coh-binding interfaces supporting a dual-binding mode, which may confer increased positional adjustment of the different complex components. Ruminococcus flavefaciens’ cellulosome is assembled from a repertoire of 223 Doc-containing proteins classified into 6 groups. Recent studies revealed that Docs of groups 3 and 6 are recruited to the cellulosome via a single-binding mode mechanism with an adaptor scaffoldin. To investigate the extent to which the single-binding mode contributes to the assembly of R. flavefaciens cellulosome, the structures of two group 1 Docs bound to Cohs of primary (ScaA) and adaptor (ScaB) scaffoldins were solved. The data revealed that group 1 Docs display a conserved mechanism of Coh recognition involving a single-binding mode. Therefore, in contrast to all cellulosomes described to date, the assembly of R. flavefaciens cellulosome involves single but not dual-binding mode Docs. Thus, this work reveals a novel mechanism of cellulosome assembly and challenges the ubiquitous implication of the dual-binding mode in the acquisition of cellulosome flexibility.

Marzola, Marco, Octávio Mateus, Neil H. Shubin, and Lars B. Clemmensen. "Cyclotosaurus naraserluki, sp. nov., a new Late Triassic cyclotosaurid (Amphibia, Temnospondyli) from the Fleming Fjord Formation of the Jameson Land Basin (East Greenland)." Journal of Vertebrate Paleontology (2017): e1303501. Abstractmarzola_et_al_2017_cyclotosaurus_greenland.pdfWebsite

ABSTRACTCyclotosaurus naraserluki, sp. nov., is a new Late Triassic capitosaurid amphibian from lacustrine deposits in the Fleming Fjord Formation of the Jameson Land Basin in Greenland. It is based on a fairly complete and well-preserved skull associated with two vertebral intercentra. Previously reported as Cyclotosaurus cf. posthumus, C. naraserluki is unique among cyclotosaurs for having the postorbitals embaying the supratemporals posteromedially. The anterior palatal vacuity presents an autapomorphic complete subdivision by a wide medial premaxillary-vomerine bony connection. The parasphenoid projects between the pterygoids and the exoccipitals, preventing a suture between the two, a primitive condition shared with Rhinesuchidae, Eryosuchus, and Kupferzellia. Within Cyclotosaurus, the Greenlandic skull has a distinctive combination of circular choanae (shared with C. ebrachensis, C. posthumus, and C. robustus) and a convex posteromedial margin of the tabulars (also present in C. ebrachensis and C. intermedius). A phylogenetic analysis indicates that C. naraserluki is the sister taxon of the middle Norian C. mordax from southern Germany, with which it shares a pair of premaxillary foramina. Cyclotosaurus is one of the most successful and diverse genera of Late Triassic temnospondyls, with at least eight species reported from middle Carnian to late Norian. Cyclotosaurus naraserluki is the largest amphibian ever reported from Greenland and one of the Late Triassic vertebrates with the highest northern paleolatitude currently known.http://zoobank.org/urn:lsid:zoobank.org:pub:43AAA541-031C-4EE1-B819-4846EBBD1BBBSUPPLEMENTAL DATA?Supplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Marzola, M., O. Mateus, N. H. Shubin, and L. B. Clemmensen. 2017. Cyclotosaurus naraserluki, sp. nov., a new Late Triassic cyclotosaurid (Amphibia, Temnospondyli) from the Fleming Fjord Formation of the Jameson Land Basin (East Greenland). Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1303501.ABSTRACTCyclotosaurus naraserluki, sp. nov., is a new Late Triassic capitosaurid amphibian from lacustrine deposits in the Fleming Fjord Formation of the Jameson Land Basin in Greenland. It is based on a fairly complete and well-preserved skull associated with two vertebral intercentra. Previously reported as Cyclotosaurus cf. posthumus, C. naraserluki is unique among cyclotosaurs for having the postorbitals embaying the supratemporals posteromedially. The anterior palatal vacuity presents an autapomorphic complete subdivision by a wide medial premaxillary-vomerine bony connection. The parasphenoid projects between the pterygoids and the exoccipitals, preventing a suture between the two, a primitive condition shared with Rhinesuchidae, Eryosuchus, and Kupferzellia. Within Cyclotosaurus, the Greenlandic skull has a distinctive combination of circular choanae (shared with C. ebrachensis, C. posthumus, and C. robustus) and a convex posteromedial margin of the tabulars (also present in C. ebrachensis and C. intermedius). A phylogenetic analysis indicates that C. naraserluki is the sister taxon of the middle Norian C. mordax from southern Germany, with which it shares a pair of premaxillary foramina. Cyclotosaurus is one of the most successful and diverse genera of Late Triassic temnospondyls, with at least eight species reported from middle Carnian to late Norian. Cyclotosaurus naraserluki is the largest amphibian ever reported from Greenland and one of the Late Triassic vertebrates with the highest northern paleolatitude currently known.http://zoobank.org/urn:lsid:zoobank.org:pub:43AAA541-031C-4EE1-B819-4846EBBD1BBBSUPPLEMENTAL DATA?Supplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Marzola, M., O. Mateus, N. H. Shubin, and L. B. Clemmensen. 2017. Cyclotosaurus naraserluki, sp. nov., a new Late Triassic cyclotosaurid (Amphibia, Temnospondyli) from the Fleming Fjord Formation of the Jameson Land Basin (East Greenland). Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1303501.

Mendes, Jorge, Jácome Cunha, Francisco Duarte, Gregor Engels, João Saraiva, and Stefan Sauer. "Systematic Spreadsheet Construction Processes." IEEE Symposium on Visual Languages and Human-Centric Computing (VL/HCC). Raleigh, North Carolina, USA: IEEE, 2017. paper.pdf
Soares A., Estevão M. S., Marques Kovalishyn Latino Aires-de-Sousa Ramos Viveiros Ma M. M. B. * V. "3. Synthesis and Biological Evaluation of Hybrid 1,5-and 2,5-Disubstituted Indoles as Potentially New Antitubercular Agents." Med. Chem. . 13 (2017): 439-447.
Silva, M. A. G., M. P. Cunha, A. Pinho Ramos, B. Sena da Fonseca, and F. F. S. Pinho. "Accelerated action of external sulfate and chloride to study corrosion of tensile steel in reinforced concrete." Materiales de Construcción. 67.328 (2017).
Silva, Manuel A. G., Manuel P. Cunha, António P. Ramos, Bruno S. Fonseca, and Fernando F. S. Pinho. "Accelerated action of external sulfate and chloride to study corrosion of tensile steel in reinforced concrete." Materiales de Construcción.ISSN-L: 0465-2746; http://dx.doi.org/10.3989/mc.2017.10116 (2017).
Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Analytical model with uncoupled adhesion laws for the bond failure prediction of curved FRP-concrete joints subjected to temperature." Theoretical and Applied Fracture Mechanics. 89 (2017): 63-78. Abstract

The strengthening of structures such as columns, beams, arches or slabs with Fibre Reinforced Polymers (FRP) has been the focus of several studies. However, the studies dedicated to the FRP debonding phenomenon of curved bonded joints affected by elevated temperatures are surprisingly limited and no studies on this topic are known, at present, to use nonlinear analytical or numerical approaches. Still, the available studies found in the literature are unanimous in affirming that the debonding phenomenon on such curved interfaces demands the interaction between Fracture Modes I and II. The present work aims to develop an analytical solution capable of simulating the debonding process of curved CFRP-toconcrete interfaces with a constant radius subjected to mechanical and/or thermal loads. Some examples are presented in which the influence of the radius of the interface and the temperature level is analysed. The analytical solution proposed here is based on adhesion laws in which, in the case ofMode II, an exponential bond vs. relative displacement law with temperature dependency is assumed, whereas the Mode I adhesive law is based on a linear with fragile rupture law with the same temperature dependency as Mode II.

Mateus, Octávio, Marco Marzola, Anne S. Schulp, Louis L. Jacobs, Michael J. Polcyn, Vladimir Pervov, António Olímpio Gonçalves, and Maria Luisa Morais. "Angolan ichnosite in a diamond mine shows the presence of a large terrestrial mammaliamorph, a crocodylomorph, and sauropod dinosaurs in the Early Cretaceous of Africa." Palaeogeography, Palaeoclimatology, Palaeoecology. 471 (2017): 220-232. Abstractmateus_et_al_2017_angolan_ichnosite_catoca.pdfWebsite

Abstract We report here new and the first mammaliamorph tracks from the Early Cretaceous of Africa. The tracksite, that also bears crocodylomorph and sauropod dinosaurian tracks, is in the Catoca diamond mine, Lunda Sul Province, Angola. The mammaliamorph tracks have a unique morphology, attributed to Catocapes angolanus ichnogen. et ichnosp. nov. and present an anterolateral projection of digit I and V. The tracks with an average length of 2.7 cm and width of 3.2 cm are the largest mammaliamorph tracks known from the Early Cretaceous unmatched in size in the skeletal fossil record. The crocodylomorph trackways and tracks are attributed to Angolaichnus adamanticus ichnogen. et ichnosp. nov. (‘ichnofamily’ Batrachopodidae) and present a functionally pentadactyl pes, an extremely outwardly rotated handprint, and an unusual tetradactyl and plantigrade manus. One medium-sized sauropod dinosaur trackway preserved skin impressions of a trackmaker with stride length of 1.6 m; a second is that of a small-sized sauropod trackmaker with a pace length of 75 cm.

Franco, F., Nunes A. Antão, Vicente M. da Silva, and N. M. C. Guerra Bearing capacity of shallow impervious footing in soil under sub-vertical seepage. Pro eedings of the 18 th International Conference on Soil Mechanics and Geotechnical Engineering. Seoul, Coreia, 2017.
Brás, C. P., A. Fisher, J. J. Júdice, K. Schönefeld, and S. Seifert. "A block active set algorithm with spectral choice line search for the symmetric eigenvalue complementarity problem." Applied Mathematics and Computation. 294 (2017): 36-48. AbstractWebsite

In this paper, we address the solution of the symmetric eigenvalue complementarity problem (EiCP) by treating an equivalent reformulation of finding a stationary point of a fractional quadratic program on the unit simplex. The spectral projected-gradient (SPG) method has been recommended to this optimization problem when the dimension of the symmetric EiCP is large and the accuracy of the solution is not a very important issue. We suggest a new algorithm which combines elements from the SPG method and the block active set method, where the latter was originally designed for box constrained quadratic programs. In the new algorithm the projection onto the unit simplex in the SPG method is replaced by the much cheaper projection onto a box. This can be of particular advantage for large and sparse symmetric EiCPs. Global convergence to a solution of the symmetric EiCP is established. Computational experience with medium and large symmetric EiCPs is reported to illustrate the efficacy and efficiency of the new algorithm.