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2015
Cavalheiro, David, Francesc Moll, and Stanimir Valtchev. "Novel {UHF} Passive Rectifier with Tunnel {FET} Devices." 2015 {IEEE} Computer Society Annual Symposium on {VLSI}. Institute of Electrical {&} Electronics Engineers ({IEEE}), 2015. Abstract
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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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Moniz, António. "Assessing Technologies: Global Patterns of Trust and Distrust. Report on one session at the XVIII World Congress of Sociology." Technikfolgenabschätzung –{} Theorie und Praxis. 24 (2015). AbstractWebsite

Technology assessment (TA) had never been treated as a relevant topic within the International Sociological Association (ISA) before. The first steps towards establishing this association were taken in 1948, at the initiative of the Social Science Department of UNESCO. Its formal foundation was in 1949. The World Congress of Sociology in Japan was hopefully the beginning of continuous integration of TA into the thematic sessions within the ISA.

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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Marques, A. C., L. Santos, M. N. Costa, J. M. Dantas, P. Duarte, A. Gonçalves, R. Martins, C. A. Salgueiro, and E. Fortunato. "{Office Paper Platform for Bioelectrochromic Detection of Electrochemically Active Bacteria using Tungsten Trioxide Nanoprobes}." Scientific Reports. 5 (2015): 9910. AbstractWebsite

Electrochemically active bacteria (EAB) have the capability to transfer electrons to cell exterior, a feature that is currently explored for important applications in bioremediation and biotechnology fields. However, the number of isolated and characterized EAB species is still very limited regarding their abundance in nature. Colorimetric detection has emerged recently as an attractive mean for fast identification and characterization of analytes based on the use of electrochromic materials. In this work, WO3 nanoparticles were synthesized by microwave assisted hydrothermal synthesis and used to impregnate non-treated regular office paper substrates. This allowed the production of a paper-based colorimetric sensor able to detect EAB in a simple, rapid, reliable, inexpensive and eco-friendly method. The developed platform was then tested with Geobacter sulfurreducens, as a proof of concept. G. sulfurreducens cells were detected at latent phase with an RGB ratio of 1.10 ± 0.04, and a response time of two hours.

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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Wojcik, Pawel Jerzy, Lidia Santos, Luis Pereira, Rodrigo Martins, and Elvira Fortunato. "{Tailoring nanoscale properties of tungsten oxide for inkjet printed electrochromic devices.}." Nanoscale. 7 (2015): 1696-708. AbstractWebsite

This paper focuses on the engineering procedures governing the synthesis of tungsten oxide nanocrystals and the formulation of printable dispersions for electrochromic applications. By that means, we aim to stress the relevancy of a proper design strategy that results in improved physicochemical properties of nanoparticle loaded inks. In the present study inkjet printable nanostructured tungsten oxide particles were successfully synthesized via hydrothermal processes using pure or acidified aqueous sol-gel precursors. Based on the proposed scheme, the structure and morphology of the nanoparticles were tailored to ensure the desired printability and electrochromic performance. The developed nanomaterials with specified structures effectively improved the electrochemical response of printed films, resulting in 2.5 times higher optical modulation and 2 times faster coloration time when compared with pure amorphous films.

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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Amaro, Pedro, Beatrice Franke, Julian J. Krauth, Marc Diepold, Filippo Fratini, Laleh Safari, Jorge Machado, Aldo Antognini, Franz Kottmann, Paul Indelicato, Randolf Pohl, and Jose Paulo Santos. "Quantum interference effects in laser spectroscopy of muonic hydrogen, deuterium, and helium-3." Physical Review A. 92 (2015): 022514-7. 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., P. Amaro, J. Machado, and J. P. Santos. "Single differential electron impact ionization cross sections in the binary-encounter- Bethe approximation for the low binding energy regime." Journal of Physics B: Atomic, Molecular and Optical Physics. 48 (2015): 1-9. AbstractWebsite

Journal of Physics B: Atomic, Molecular and Optical Physics, 48(2015) 185202. doi:10.1088/0953-4075/48/18/185202

Amaro, Pedro, Beatrice Franke, Julian J. Krauth, Marc Diepold, Filippo Fratini, Laleh Safari, Jorge Machado, Aldo Antognini, Franz Kottmann, Paul Indelicato, Randolf Pohl, and José Paulo Santos. "{Quantum interference effects in laser spectroscopy of muonic hydrogen, deuterium, and helium-3}." Physical Review A. 92 (2015): 022514. AbstractWebsite
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Guerra, M., P. Amaro, J. Machado, and J. P. Santos. "{Single differential electron impact ionization cross sections in the binary-encounter-Bethe approximation for the low binding energy regime}." Journal of Physics B: Atomic, Molecular and Optical Physics. 48 (2015): 1-9. AbstractWebsite
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Madeira, T. I., J. M. Sampaio, M. Guerra, F. Parente, P. Indelicato, J. P. Santos, and J. P. Marques. "Relativistic calculation of K-, L- and M-shell x-ray fluorescence yields for Ba." Physica Scripta. 90 (2015): 1-3. AbstractWebsite

Physica Scripta, 90(2015) 054009. doi:10.1088/0031-8949/90/5/054009

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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Martins, J. F., P. Pereira, A. J. Pires, and V. F. Pires. "A new teaching tool to enhance power quality assessment." Industrial Electronics Society, IECON 2015 - 41st Annual Conference of the IEEE. Yokohama, Japan: IEEE-IES, 2015. 004158-004162. Abstract

The study and assessment of Power Quality issues is nowadays a very important subject, particularly regarding Cyber-physical and Industrial Agents based systems, which are extremely sensitive to Power Quality disturbances. Giving students or engineers practical experience in this field requires a large investment from teaching institutions. This paper presents a laboratory device that emulates Power Quality disturbances in order to provide the required experimental expertize in the subject. It addresses limiting aspects such as harmonic distortion, flicker, sags, swells and transients. The developed system presents a good opportunity for technicians, even without deep knowledge on the field of power quality, to learn basic principles and be able to identify Power Quality events. Since the system is based on real data, represents a valuable approach giving trainees practical knowledge on the field.