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2017
Pardal, T., S. Messias, M. Sousa, A. S. R. Machado, C. M. Rangel, D. Nunes, JV Pinto, R. Martins, and M. N. {Da Ponte}. "{Syngas production by electrochemical CO2 reduction in an ionic liquid based-electrolyte}." Journal of CO2 Utilization. 18 (2017). Abstract

© 2017 Elsevier Ltd. Graphical abstract: The electrochemical reduction of carbon dioxide dissolved in a solution of water and ionic liquid as electrolyte, at high-pressure and near room-temperature, is reported. This work describes an electro-deposition strategy for the preparation of copper substrate cathodes, coated with bimetallic zinc-copper films, obtained from deep-eutectic solvents plating baths. The prepared bimetallic cathodes showed electrochemical activity for syngas production in 1-butyl-3-methylimidazolium triflate, with yields of 85N$μ$L (normal microliter)cm−2C−1/170N$μ$Lcm−2h−1, high selectivities, tunable H2/CO ratio and low energetic requirements.

Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Uncertainty Characterization of the Orthogonal Procrustes Problem with Arbitrary Covariance Matrices}." Pattern Recognition. 61 (2017): 210-220. Abstract
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Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Uncertainty Characterization of the Orthogonal Procrustes Problem with Arbitrary Covariance Matrices}." Pattern Recognition. 61 (2017): 210-220. Abstract
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Goswami, S., S. Nandy, A. N. Banerjee, A. Kiazadeh, G. R. Dillip, JV Pinto, S. W. Joo, R. Martins, and E. Fortunato. "{“Electro-Typing” on a Carbon-Nanoparticles-Filled Polymeric Film using Conducting Atomic Force Microscopy}." Advanced Materials. 29 (2017). Abstract

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Next-generation electrical nanoimprinting of a polymeric data sheet based on charge trapping phenomena is reported here. Carbon nanoparticles (CNPs) (waste carbon product) are deployed into a polymeric matrix (polyaniline) (PANI) as a charge trapping layer. The data are recorded on the CNPs-filled polyaniline device layer by “electro-typing” under a voltage pulse (VET, from ±1 to ±7 V), which is applied to the device layer through a localized charge-injection method. The core idea of this device is to make an electrical image through the charge trapping mechanism, which can be “read” further by the subsequent electrical mapping. The density of stored charges at the carbon–polyaniline layer, near the metal/polymer interface, is found to depend on the voltage amplitude, i.e., the number of injected charge carriers. The relaxation of the stored charges is studied by different probe voltages and for different devices, depending on the percolation of the CNPs into the PANI. The polymeric data sheet retains the recorded data for more than 6 h, which can be refreshed or erased at will. Also, a write–read–erase–read cycle is performed for the smallest “bit” of stored information through a single contact between the probe and the device layer.

2016
Doutor, Paulo, Paula Rodrigues, Maria Ceu do Soares, and Fabio A. C. C. Chalub. "Optimal vaccination strategies and rational behaviour in seasonal epidemics." JOURNAL OF MATHEMATICAL BIOLOGY. 73 (2016): 1437-1465. Abstract

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Cardoso, Pedro, Pedro Amaro, Jose Paulo Santos, Joaquim T. de Assis, and Maria Luisa Carvalho. "Determination of Nickel and Manganese Contaminants in Pharmaceutical Iron Supplements using Energy Dispersive X-ray Fluorescence." Applied Spectroscopy (2016). AbstractWebsite

In this study, we investigate the capability of energy dispersive X-ray fluorescence (EDXF) spectrometry in a triaxial geometry apparatus as a fast and nondestructive determination method of both dominant and contaminant elements in pharmaceutical iron supplements. The following iron supplements brands with their respective active ingredients were analyzed: Neutrofer fólico (iron gylcinate), Anemifer (iron(II) sulfate monohydrate), Noripurum (iron(III)-hydroxide polymaltose complex), Sulferbel (iron(II) sulfate monohydrate), and Combiron Fólico (carbonyl iron). Although we observe a good agreement between the iron content obtained by the present method and that indicated in the supplement's prescribed dose, we observe contamination by manganese and nickel of up to 180 μg and 36 μg, respectively. These contents correspond to 7.2% and 14.4% of the permitted daily exposure of manganese and nickel, respectively, for an average adult individual as determined by the European Medicine Agency (EMEA). The method was successfully validated against the concentrations of several certified reference materials of biological light matrices with similar concentrations of contaminants. Moreover, we also validated our method by comparing the concentrations with those obtained with the inductively coupled plasma-atomic emission technique.

Pohl, R., and CREMA Collaboration. "Laser Spectroscopy of Muonic Atoms and Ions." JPS Conf. Proc. (2016): 1-12. AbstractWebsite
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Almeida, Bernardo F., Isabel Correia, and Francisco Saldanha-da-Gama. "Priority-based heuristics for the multi-skill resource constrained project scheduling problem." Expert Systems with Applications. 57 (2016): 91-103. AbstractWebsite
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Maiti, B. K., I. Moura, J. J. Moura, and S. R. Pauleta. "The small iron-sulfur protein from the ORP operon binds a [2Fe-2S] cluster." Biochim Biophys Acta. 1857 (2016): 1422-9. AbstractWebsite

A linear cluster formulated as [S2MoS2CuS2MoS2](3-), a unique heterometallic cluster found in biological systems, was identified in a small monomeric protein (named as Orange Protein). The gene coding for this protein is part of an operon mainly present in strict anaerobic bacteria, which is composed (in its core) by genes coding for the Orange Protein and two ATPase proposed to contain Fe-S clusters. In Desulfovibrio desulfuricans G20, there is an ORF, Dde_3197 that encodes a small protein containing several cysteine residues in its primary sequence. The heterologously produced Dde_3197 aggregates mostly in inclusion bodies and was isolated by unfolding with a chaotropic agent and refolding by dialysis. The refolded protein contained sub-stoichiometric amounts of iron atoms/protein (0.5+/-0.2), but after reconstitution with iron and sulfide, high iron load contents were detected (1.8+/-0.1 or 3.4+/-0.2) using 2- and 4-fold iron excess. The visible absorption spectral features of the iron-sulfur clusters in refolded and reconstituted Dde_3197 are similar and resemble the ones of [2Fe-2S] cluster containing proteins. The refolded and reconstituted [2Fe-2S] Dde_3197 are EPR silent, but after reduction with dithionite, a rhombic signal is observed with gmax=2.00, gmed=1.95 and gmin=1.92, consistent with a one-electron reduction of a [2Fe-2S](2+) cluster into a [2Fe-2S](1+) state, with an electron spin of S=(1/2). The data suggests that Dde_3197 can harbor one or two [2Fe-2S] clusters, one being stable and the other labile, with quite identical spectroscopic properties, but stable to oxygen.

Ito, Y., T. Tochio, H. Ohashi, M. Yamashita, S. Fukushima, M. Polasik, K. Słabkowska, Ł. Syrocki, E. Szymańska, J. Rzadkiewicz, P. Indelicato, J. P. Marques, M. C. Martins, J. P. Santos, and F. Parente. "Kα1,2x-ray linewidths, asymmetry indices, and [KM]shake probabilities in elements Ca to Ge and comparison with theory for Ca, Ti, and Ge." Physical Review A. 94 (2016): 042506-11. AbstractWebsite
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Marques, J. P., P. Indelicato, F. Parente, J. M. Sampaio, and J. P. Santos. "Ground-state Landé <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>g</mi></math></span> factors for selected ions along the boron isoelectronic sequence." Physical Review A. 94 (2016): 042504. AbstractWebsite

Land\'e $g$ factors for the fine-structure $1{s}^{2}2{s}^{2}2p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ and $^{2}P_{3/2}$ levels in the boron isoelectronic sequence for selected $Z$ values have been calculated using the multiconfiguration Dirac-Fock method with both quantum-electrodynamic and electronic correlation corrections included. All-order Breit and vacuum polarization corrections were included in the calculation, with a fully optimized active set wave function. The results are compared with the available theoretical data, showing a very good agreement.

Marques, J. P., P. Indelicato, F. Parente, J. M. Sampaio, and J. P. Santos. "Ground-state Landé g factors for selected ions along the boron isoelectronic sequence." Physical Review A. 94 (2016): 042504. AbstractWebsite

Land\'e $g$ factors for the fine-structure $1{s}^{2}2{s}^{2}2p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2}$ and $^{2}P_{3/2}$ levels in the boron isoelectronic sequence for selected $Z$ values have been calculated using the multiconfiguration Dirac-Fock method with both quantum-electrodynamic and electronic correlation corrections included. All-order Breit and vacuum polarization corrections were included in the calculation, with a fully optimized active set wave function. The results are compared with the available theoretical data, showing a very good agreement.

Sampaio, J. M., T. I. Madeira, M. Guerra, F. Parente, P. Indelicato, J. P. Santos, and J. P. Marques. "Relativistic calculations of K-, L- and M-shell X-ray production cross-sections by electron impact for Ne, Ar, Kr, Xe, Rn and Uuo." Journal of Quantitative Spectroscopy and Radiative Transfer. 182 (2016): 87-93. AbstractWebsite

Journal of Quantitative Spectroscopy and Radiative Transfer, 182 + (2016) 87-93. doi:10.1016/j.jqsrt.2016.05.012

Branquinho, Rita, Ana Santa, Emanuel Carlos, Daniela Salgueiro, Pedro Barquinha, Rodrigo Martins, and Elvira Fortunato. "{Solution Combustion Synthesis: Applications in Oxide Electronics}." Developments in Combustion Technology. Eds. Kyprianidis G. Konstantinos, and Jan Skvaril. InTech, 2016. 397-417. Abstract

Oxide-based electronics have been well established as an alternative to silicon technology; however, typical processing requires complex, high-vacuum equipment, which is a major drawback, particularly when targeting low-cost applications. The possibility to deposit the materials by low-cost techniques such as inkjet printing has drawn tremendous interest in solution processible materials for electronic applications; however, high processing temperatures still required. To overcome this issue, solution combustion synthesis has been recently pursued. Taking advantage of the exothermic nature of the reaction as a source of energy for localized heating, the precursor solutions can be converted into oxides at lower process temperatures. Theoretically, this can be applied to any metal ions to produce the desired oxide, opening unlimited possibilities to materials' composition and combinations. Solution combustion synthesis has been applied for the production of semiconductor thin films based on ZnO, In2O3, SnO2 and combinations of these oxides, and also for high $ąppa$ dielectrics (Al2O3). All of which are required for numerous electronic devices and applications such as fully oxide-based thin-film transistors (TFTs). The properties of produced thin films are highly dependent on the precursor solution characteristics; hence, the influence of several processing parameters; organic fuel, solvent and annealing temperature was studied. Although precursor solution degradation/oxide formation mechanisms are not yet fully understood, particularly for thin films, we demonstrate that high-performance devices are obtained with combustion solution-based metal oxide thin films. The results clearly show that solution combustion synthesis is becoming one of the most promising methods for low-temperature flexible electronics.

Lorenz, M., et al. "{The 2016 oxide electronic materials and oxide interfaces roadmap}." Journal of Physics D: Applied Physics. 49 (2016): 433001. AbstractWebsite

Oxide electronic materials provide a plethora of possible applications and offer ample opportunity for scientists to probe into some of the exciting and intriguing phenomena exhibited by oxide systems and oxide interfaces. In addition to the already diverse spectrum of properties, the nanoscale form of oxides provides a new dimension of hitherto unknown phenomena due to the increased surface-to-volume ratio. Oxide electronic materials are becoming increasingly important in a wide range of applications including transparent electronics, optoelectronics, magnetoelectronics, photonics, spintronics, thermoelectrics, piezoelectrics, power harvesting, hydrogen storage and environmental waste management. Synthesis and fabrication of these materials, as well as processing into particular device structures to suit a specific application is still a challenge. Further, characterization of these materials to understand the tunability of their properties and the novel properties that evolve due to their nanostructured nature is another facet of the challenge. The research related to the oxide electronic field is at an impressionable stage, and this has motivated us to contribute with a roadmap on 'oxide electronic materials and oxide interfaces'. This roadmap envisages the potential applications of oxide materials in cutting edge technologies and focuses on the necessary advances required to implement these materials, including both conventional and novel techniques for the synthesis, characterization, processing and fabrication of nanostructured oxides and oxide-based devices. The contents of this roadmap will highlight the functional and correlated properties of oxides in bulk, nano, thin film, multilayer and heterostructure forms, as well as the theoretical considerations behind both present and future applications in many technologically important areas as pointed out by Venkatesan. The contributions in this roadmap span several thematic groups which are represented by the following authors: novel field effect transistors and bipolar devices by Fortunato, Grundmann, Boschker, Rao, and Rogers; energy conversion and saving by Zaban, Weidenkaff, and Murakami; new opportunities of photonics by Fompeyrine, and Zuniga-Perez; multiferroic materials including novel phenomena by Ramesh, Spaldin, Mertig, Lorenz, Srinivasan, and Prellier; and concepts for topological oxide electronics by Kawasaki, Pentcheva, and Gegenwart. Finally, Miletto Granozio presents the European action 'towards oxide-based electronics' which develops an oxide electronics roadmap with emphasis on future nonvolatile memories and the required technologies. In summary, we do hope that this oxide roadmap appears as an interesting up-to-date snapshot on one of the most exciting and active areas of solid state physics, materials science, and chemistry, which even after many years of very successful development shows in short intervals novel insights and achievements.

Carlos, Emanuel, Rita Branquinho, Asal Kiazadeh, Pedro Barquinha, Rodrigo Martins, and Elvira Fortunato. "{UV-Mediated Photochemical Treatment for Low-Temperature Oxide-Based Thin-Film Transistors}." ACS Applied Materials {&} Interfaces. 8 (2016): 31100-31108. AbstractWebsite

Solution processing of amorphous metal oxides has lately been used as an option to implement in flexible electronics, allowing a reduction of the associated costs and high performance. However, the research has focused more on the semiconductor layer rather than on the insulator layer, which is related to the stability and performance of the devices. This work aims to evaluate amorphous aluminum oxide thin films produced by combustion synthesis and the influence of far-ultraviolet (FUV) irradiation on the properties of the insulator on thin-film transistors (TFTs) using different semiconductors, in order to have compatibility with flexible substrates. An optimized dielectric layer was obtained for an annealing of 30 min assisted by FUV exposure. These thin films were applied in gallium–indium–zinc oxide TFTs as dielectrics showing the best results for TFTs annealed at 180 °C with FUV irradiation: good reproducibility with a subthreshold slope of 0.11 ± 0.01 V dec –1 and a turn-on voltage of −0.12 ± 0.05 V...

Rahangdale, H. V., D. Mitra, P. K. Das, S. De, M. Guerra, J. P. Santos, and S. Saha. "Spectroscopic investigations of L-shell ionization in heavy elements by electron impact." Journal of Quantitative Spectroscopy and Radiative Transfer. 174 (2016): 79-87. AbstractWebsite

Journal of Quantitative Spectroscopy and Radiative Transfer, 174 + (2016) 79-87. doi:10.1016/j.jqsrt.2016.01.026

Amaro, Pedro, Filippo Fratini, Laleh Safari, Jorge Machado, Mauro Guerra, Paul Indelicato, and Jose Paulo Santos. "Relativistic evaluation of the two-photon decay of the metastable 1s22s2p 3P0 state in berylliumlike ions with an effective-potential model." Physical Review A. 93 (2016): 032502-8. AbstractWebsite

The two-photon $1{s}^{2}2s2p\phantom{\rule{0.16em}{0ex}}{}^{3}{P}_{0}\ensuremath{\rightarrow}1{s}^{2}{s}^{2}\phantom{\rule{0.16em}{0ex}}{}^{1}{S}_{0}$ transition in berylliumlike ions is investigated theoretically within a fully relativistic framework and a second-order perturbation theory. We focus our analysis on how electron correlation, as well as the negative-energy spectrum, can affect the forbidden $E1M1$ decay rate. For this purpose, we include the electronic correlation via an effective local potential and within a single-configuration-state model. Due to its experimental interest, evaluations of decay rates are performed for berylliumlike xenon and uranium. We find that the negative-energy contribution can be neglected at the present level of accuracy in the evaluation of the decay rate. On the other hand, if contributions of electronic correlation are not carefully taken into account, it may change the lifetime of the metastable state by up to 20%. By performing a fully relativistic $jj$-coupling calculation, we find a decrease of the decay rate by two orders of magnitude compared to nonrelativistic $LS$-coupling calculations, for the selected heavy ions.

Carepo, M. S., C. Carreira, R. Grazina, M. E. Zakrzewska, A. Dolla, C. Aubert, S. R. Pauleta, J. J. Moura, and I. Moura. "Orange protein from Desulfovibrio alaskensis G20: insights into the Mo-Cu cluster protein-assisted synthesis." J Biol Inorg Chem. 21 (2016): 53-62. AbstractWebsite

A novel metalloprotein containing a unique [S2MoS2CuS2MoS2](3-) cluster, designated as Orange Protein (ORP), was isolated for the first time from Desulfovibrio gigas, a sulphate reducer. The orp operon is conserved in almost all sequenced Desulfovibrio genomes and in other anaerobic bacteria, however, so far D. gigas ORP had been the only ORP characterized in the literature. In this work, the purification of another ORP isolated form Desulfovibrio alaskensis G20 is reported. The native protein is monomeric (12443.8 +/- 0.1 Da by ESI-MS) and contains also a MoCu cluster with characteristic absorption bands at 337 and 480 nm, assigned to S-Mo charge transfer bands. Desulfovibrio alaskensis G20 recombinant protein was obtained in the apo-form from E. coli. Cluster reconstitution studies and UV-visible titrations with tetrathiomolybdate of the apo-ORP incubated with Cu ions indicate that the cluster is incorporated in a protein metal-assisted synthetic mode and the protein favors the 2Mo:1Cu stoichiometry. In Desulfovibrio alaskensis G20, the orp genes are encoded by a polycistronic unit composed of six genes whereas in Desulfovibrio vulgaris Hildenborough the same genes are organized into two divergent operons, although the composition in genes is similar. The gene expression of ORP (Dde_3198) increased 6.6 +/- 0.5 times when molybdate was added to the growth medium but was not affected by Cu(II) addition, suggesting an involvement in molybdenum metabolism directly or indirectly in these anaerobic bacteria.

Amaro, Pedro, Filippo Fratini, Laleh Safari, Jorge Machado, Mauro Guerra, Paul Indelicato, and José Paulo Santos. "{Relativistic evaluation of the two-photon decay of the metastable $1s^2\,2s\,2p\,^3P_0$ state in berylliumlike ions with an effective-potential model}." Physical Review A. 93 (2016): 032502. AbstractWebsite
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Oliveira, João P., and João Goes. "Advanced Amplification Techniques for Nanoscale CMOS in the Context of IoT Node Sensors." 22nd International Conference Mixed Design of Integrated Circuits & Systems (MIXDES’16). Lodz, Poland: IEEE, 2016.
Sampaio, J. M., M. Guerra, F. Parente, T. I. Madeira, P. Indelicato, J. P. Santos, and J. P. Marques. "Calculations of photo-induced X-ray production cross-sections in the energy range 1–150 keV and average fluorescence yields for Zn, Cd and Hg." Atomic Data and Nuclear Data Tables. 111-112 (2016): 67-86. AbstractWebsite

Atomic Data and Nuclear Data Tables, 111-112 (2016) 67-86. doi:10.1016/j.adt.2016.02.001

Ramos, I., I. M. Pataco, M. P. Mourinho, F. Lidon, F. Reboredo, M. F. Pessoa, M. L. Carvalho, J. P. Santos, and M. Guerra. "Elemental mapping of biofortified wheat grains using micro X-ray fluorescence." Spectrochimica Acta Part B: Atomic Spectroscopy. 120 (2016): 30-36. AbstractWebsite

Spectrochimica Acta Part B: Atomic Spectroscopy, 120 (2016) 30-36. doi:10.1016/j.sab.2016.03.014

Röder, Marko, et al. "{Coulomb dissociation of $^{20,21}$N}." Physical Review C. 93 (2016): 065807. AbstractWebsite
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