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2014
Maiti, B. K., L. B. Maia, K. Pal, B. Pakhira, T. Aviles, I. Moura, S. R. Pauleta, J. L. Nunez, A. C. Rizzi, CD Brondino, S. Sarkar, and J. J. Moura. "One electron reduced square planar bis(benzene-1,2-dithiolato) copper dianionic complex and redox switch by O2/HO(-)." Inorg Chem. 53 (2014): 12799-808. AbstractWebsite

The complex [Ph4P]2[Cu(bdt)2] (1(red)) was synthesized by the reaction of [Ph4P]2[S2MoS2CuCl] with H2bdt (bdt = benzene-1,2-dithiolate) in basic medium. 1(red) is highly susceptible toward dioxygen, affording the one electron oxidized diamagnetic compound [Ph4P][Cu(bdt)2] (1(ox)). The interconversion between these two oxidation states can be switched by addition of O2 or base (Et4NOH = tetraethylammonium hydroxide), as demonstrated by cyclic voltammetry and UV-visible and EPR spectroscopies. Thiomolybdates, in free or complex forms with copper ions, play an important role in the stability of 1(red) during its synthesis, since in its absence, 1(ox) is isolated. Both 1(red) and 1(ox) were structurally characterized by X-ray crystallography. EPR experiments showed that 1(red) is a Cu(II)-sulfur complex and revealed strong covalency on the copper-sulfur bonds. DFT calculations confirmed the spin density delocalization over the four sulfur atoms (76%) and copper (24%) atom, suggesting that 1(red) has a "thiyl radical character". Time dependent DFT calculations identified such ligand to ligand charge transfer transitions. Accordingly, 1(red) is better described by the two isoelectronic structures [Cu(I)(bdt2, 4S(3-,)*)](2-) <--> [Cu(II)(bdt2, 4S(4-))](2-). On thermodynamic grounds, oxidation of 1(red) (doublet state) leads to 1(ox) singlet state, [Cu(III)(bdt2, 4S(4-))](1-).

Cismasiu, Corneliu, Filipe Amarante P. dos Santos, and Ana I. M. Rodrigues. "Experimental and FE updating techniques for the unseating vulnerability assessment of a footbridge structure." The 4th International Conference on Dynamics, Vibration and Control. Shanghai, China: Shanghai Institute of Applied Mathematics and Mechanics, 2014. icdvc_2014.pdf
Nunes, D., A. Pimentel, P. Barquinha, P. A. Carvalho, E. Fortunato, and R. Martins. "Cu2O polyhedral nanowires produced by microwave irradiation." Journal of Materials Chemistry C. 2 (2014): 6097-6103. AbstractWebsite
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Santos, Lidia, Joana P. Neto, Ana Crespo, Daniela Nunes, Nuno Costa, Isabel M. Fonseca, Pedro Barquinha, Luis Pereira, Jorge Silva, Rodrigo Martins, and Elvira Fortunato. "WO3 Nanoparticle-Based Conformable pH Sensor." Acs Applied Materials & Interfaces. 6 (2014): 12226-12234. AbstractWebsite
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Johnston, E. M., S. Dell'acqua, S. Gorelsky, S. R. Pauleta, I. Moura, and E. I. Solomon. "Electronic structure and reactivities of resting and intermediate forms of the tetranuclear copper cluster in nitrous oxide reductase." Abstracts of Papers of the American Chemical Society. Vol. 248. Abstr Pap Am Chem S, 248. 2014. Abstract
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Moura, JJG, B. K. Maiti, C. Carreira, L. B. Maia, S. P. Carepo, S. R. Pauleta, and I. Moura. "Metal substituted rubredoxins: a sulfur rich coordination site as models for metalloenzymes." Journal of Biological Inorganic Chemistry. Vol. 19. J Biol Inorg Chem, 19. 2014. S731. Abstract
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Barrocas, B., S. Sério, A. Rovisco, Y. Nunes, A. I. de Sá, Silva M. I. da Pereira, and Melo M. E. Jorge. "{Characterization and electrochemical behaviour of nanostructured calcium samarium manganite electrodes fabricated by RF-Magnetron Sputtering}." Electrochimica Acta. 137 (2014): 99-107. AbstractWebsite

Ca1-xSmxMnO3 (0≤x≤0.4) films were successfully fabricated on Indium Tin Oxide (ITO) coated quartz glass substrates by radio frequency magnetron sputtering technique (RF- magnetron sputtering) from compacted nanosized powder targets, and subsequent annealing at 800°C in air, for 6h. X-ray diffraction shows a pure typical perovskite phase for x≥0.1. Scanning electron microscopy and atomic force microscopy revealed that the film surface is dense, with low roughness, depending on the Sm content, even though a few cracks were observed. Crystallite size was found to decrease with the Sm content. The electrodes were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS).The oxide electrode's capacitance was estimated using both techniques and the corresponding roughness factors evaluated. The values obtained from the two methods show a good agreement. A comparison between the voltammetric data and those referred in the literature allowed finding out that the redox reaction occurring at the electrode surface involves the pair Mn4+/Mn3+. EIS measurements confirm the voltammetric data and they also give additional information about the film porosity and the charge transfer resistance. This last parameter is associated with the oxidation and reduction of the pair Mn3+/Mn4+and after normalized by the roughness factor shows an increase with samarium content.

Santos, I., M. S. Diniz, M. L. Carvalho, and J. P. Santos. "Assessment of Essential Elements and Heavy Metals Content on Mytilus galloprovincialis from River Tagus Estuary." Biological Trace Element Research (2014). AbstractWebsite

Trace elemental content was analysed in edible tissues of Mytilus galloprovincialis collected in five different sampling areas near the mouth of river Tagus estuary in Lisbon. The concentrations of essential elements (S, K, Ca, Fe, Cu, Zn, As, Br and Sr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry, while toxic elements (Cr, Cd, Hg, Se and Pb) were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results show that the essential elements K and S are present at the highest concentrations in all the studied samples reaching 2,920 and 4,520 μg g(-1) (fresh weight), respectively. The highest levels of heavy metals found were in two areas close to the city for Pb and Cd, but below the maximum allowed values.

Kasthurirangan, S., J. K. Saha, A. N. Agnihotri, A. Banerjee, A. Kumar, D. Misra, J. P. Santos, A. M. Costa, P. Indelicato, T. K. Mukherjee, and L. C. Tribedi. "High-resolution x-ray spectra from highly charged Si, S and Cl ions showing evidence of fluorescence active resonant states." Journal of Physics: Conference Series. 488 (2014): 132027-2. AbstractWebsite

We have measured the x-ray spectra from highly charged Si, S and Cl ions in collisions with thin foils using a high-resolution x-ray spectrometer. The observed lines have been assigned to various transitions in H-, He- and Li-like ions. For proper identification of line positions, the theoretical calculations have been carried out using a state-of-the-art MCDF code including QED effects, with which the experimental data is in excellent agreement. We have also observed, for the first time, x-rays arising out of the decay of long-lived resonant states in the He-like ions of each species. Details will be presented.

Amado, M. P., F. Pinho, P. Faria, and I. Ramalhete. "Eco-wall modular solutions for buildings." 9th International Masonry Conference. Guimaraes - ISBN: 978-972-8692-87-2: ICM; Universidade do Minho, 2014.
R., Póvoa, Lourenço N., Horta N., and Goes J. "A Cascode-Free Single-Stage Amplifier Using a Fully-Differential Folded Voltage-Combiner." 21st IEEE International Conference on Electronics Circuits and Systems. Marseille, France: IEEE, 2014.
N., Pereira, Goes J., Rodrigues M., and Faria P. "A New Mismatch-Insensitive 1.5-Bit MDAC with Unity Feedback-Factor and Enhanced Performance." 21st IEEE International Conference on Electronics Circuits and Systems. Marseille, France: IEEE, 2014.
Amado, Miguel, Fernando Pinho, Paulina Faria, and Inês Ramalhete. "Eco-wall modular solutions for buildings." IMC2014 - 9th International Masonry Conference 2014. Universidade do Minho, Guimarães 2014.
Pinho, Fernando F. S., Válter J. G. Lúcio, Luís Moura, Nuno Travassos, and Inês Almeida. "Evaluation of cover deviation and resistance of steel anchorages in masonry walls." IMC2014 - 9th International Masonry Conference 2014. Universidade do Minho, Guimarães 2014.
Mana, Ana, and Fernando F. S. Pinho. "Influence of non-compliant fly ashes in air-lime mortars." IMC2014 - 9th International Masonry Conference 2014. Universidade do Minho, Guimarães 2014.
Mota, Bruna, Ana Carvalho, Maria Isabel Gomes, and Ana Paula Barbosa-povoa. "Supply chain environmental assessment." avniR Conference. Nouveau Siècle, Lille, France 2014. 2014_motacarvalhogomesbpovoa_avnir.pdf
Silva, João, João M. Lourenço, and Hervé Paulino. "Um Mecanismo de Caching para o Protocolo SCORe." INForum 2014 - 6º Simpósio de Informática. Porto, Portugal: Universidade do Porto, 2014. Abstract

Os protocolos de replicação parcial de dados apresentam um grande potencial de escalabilidade. O SCORe é um protocolo para replicação parcial proposto recentemente que faz uso de controlo de concorrência multi-versão. Neste artigo abordamos um dos problemas principais que afeta o desempenho deste tipo de protocolos: a localidade dos dados, i.e., pode-se dar o caso do nó local não ter uma cópia dos dados a que pretende aceder, e nesse caso é necessário realizar uma ou mais operações de leitura remota. Assim, a não ser que se empreguem técnicas para melhorar a localidade no acesso aos dados, o número de operações de leitura remota aumenta com o tamanho do sistema, acabando por afetar o desempenho do mesmo. Nesse sentido, introduzimos um mecanismo de caching que permite replicar cópias de dados remotos de maneira a que seja possível servir localmente dados remotos enquanto que se mantém a consistência dos mesmos e a escalabilidade oferecida pelo protocolo. Avaliamos o mecanismo de caching com um benchmark conhecido da literatura e os resultados experimentais mostram resultados animadores com algum aumento no desempenho do sistema e uma redução considerável da quantidade de operações de leitura remota.

Biscaia, Hugo C., Manuel A. G. Silva, and Carlos Chastre. "An experimental study of GFRP-to-concrete interfaces submitted to humidity cycles." Composite Structures. 110.April (2014): 354-368. AbstractWebsite

Systems externally reinforced by bonded fibre reinforced polymers (FRP) are widely used in the retrofitting and strengthening of reinforced concrete (RC) structures. A drawback of the usage of this technique lies on the uncertainty of the long term behaviour of those reinforcements. Researchers have paid heed to this aspect and a number of tests and alternative techniques have recently been described. An experimental programme developed to supplement work of the authors recently published and which focused on specimens not submitted to aggressive environments is described. The specimens used have the same geometry as in the previous paper, but they were exposed to salt fog cycles and dry/wet cycles with salt water for periods of 3000 h, 5000 h and 10,000 h. The interface of the glass fiber polymeric composite (GFRP)-to-concrete was characterized after the systems underwent such aggressive conditions. The GFRP wrap comprised of two layers and wet lay-up technique was used on its preparation and application. The cohesion and friction angle for GFRP-to-concrete interfaces were measured tat selected stages of ageing process and envelope failure laws were obtained based on the Mohr–Coulomb failure criterion. Changes of 27% in cohesion and 8% in the friction angle were found due to the attack of the interface and consequences of the changes are examined.

Bernardo, Vasco, André Oliveira, Filipe Amarante dos Santos, and Corneliu Cismasiu. "Vulnerabilidade e reforço sísmico de uma passagem superior pedonal pré-fabricada." 5as Jornadas Portuguesas de Engenharia de Estruturas. Lisboa, Portugal : LNEC, 2014.
Luís, Fábio C., José S. Machado, and Fernando F. S. Pinho. "Comportamento à flexão de compósitos madeira-plástico sujeitos a humedecimento." JPEE 2014 - Jornadas Portuguesas de Engenharia de Estruturas. LNEC, Lisboa 2014.
Soldado, Fábio, Fernando Alexandre, and Hervé Paulino. "Towards the Transparent Execution of Compound OpenCL Computations in Multi-CPU/Multi-GPU Environments." Euro-Par 2014 International Workshops, Revised Selected Papers, Part I. Porto, Portugal: Springer, 2014. Abstract

Currentcomputationalsystemsareheterogeneousbynature, featuring a combination of CPUs and GPUs. As the latter are becoming an established platform for high-performance computing, the focus is shifting towards the seamless programming of the heterogeneous systems as a whole. The distinct nature of the architectural and execution models in place raise several challenges, as the best hardware configuration is behavior and data-set dependent. In this paper, we focus the execution of compound computations in multi-CPU/multi-GPU environments, in the scope of Marrow algorithmic skeleton framework, the only, to the best of our knowledge, to support skeleton nesting in GPU computing. We address how these computations may be efficiently scheduled onto the target hardware, and how the system may adapt itself to changes in the CPU’s load and in the input data-set.

Poggi, F., and M. P. Amado. " Conceito de região funcional no contexto energético do território - espaço de cooperação rural - urbano." PLURIS 2014. FCG - Lisboa, PT: FA UL, 2014.
Biscaia, Hugo C., Rui Micaelo, João Teixeira, and Carlos Chastre. "Numerical analysis of FRP anchorage zones with variable width." 67 (2014): 410-426. AbstractWebsite

AbstractThe use of Fibre Reinforced Polymers (FRP) has recently become widespread in the construction industry. However, some drawbacks related to premature debonding of the FRP composites from the bonded substrates have been identified. One of the solutions proposed is the implementation of mechanical anchorage systems. Although some design guidelines have been developed, the actual knowledge continues to be rather limited. Thus, designers and researchers have not yet achieved any consensus on the efficiency of any particular anchor device in delaying or preventing the premature debonding failure mode that can occur in Externally Bonded Reinforcement (EBR) systems. This paper studies the debonding phenomenon of FRP anchoring systems with a linear variable width, with a numerical analysis based on the Distinct Element Method (DEM). Combined systems with constant and variable width are also discussed. The FRP-to-parent material interfaces are modelled with a rigid-linear softening bond–slip law. The numerical results showed that it is possible to attain the FRP rupture force with a variable width solution. This solution is particularly attractive when the bonded length is shorter than the effective bonded length because the strength of the interface can be highly incremented.

Caeiro, Frederico Almeida Gião Gonçalves, and Ayana Maria Xavier Furtado Mateus. "An R implementation of several randomness tests." AIP Conference Proceedings. 2014. 531-534. Abstract

In many statistic methods, including distribution-free methods, we assume to work with random samples. In this note, we present randtests: an R package implementation of several nonparametric randomness tests. After a brief description of the tests included in the package, we present an application to real data sets in the field of Agricultural.In many statistic methods, including distribution-free methods, we assume to work with random samples. In this note, we present randtests: an R package implementation of several nonparametric randomness tests. After a brief description of the tests included in the package, we present an application to real data sets in the field of Agricultural.

Cardoso, T., P. Pereira, V. Fernao Pires, and J. F. Martins. "Power quality and long life education." Industrial Electronics (ISIE), 2014 IEEE 23rd International Symposium on. Istanbul - Turkey 2014. 2224-2228. Abstract

This paper presents a remote laboratory linked with mobile devices for real data analysis on the field of power quality. A global system was developed from the power quality analyzer into the human machine interface devoted to the m-learning system. This m-learning system is intended to be used in a long life learning perspective. The developed remote laboratory is a good opportunity for people, even without deep knowledge on the field, to learn power quality principles in an applied way. Since the system is based on real data, is a good approach to give trainees practical knowledge on the field.