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2013
b b b b Ramos, A.M.a b, Pereira Cidade Pereira Branquinho Pereira Martins Fortunato S. a M. T. "Preparation and characterization of cellulose nanocomposite hydrogels as functional electrolytes." Solid State Ionics. 242 (2013): 26-32. AbstractWebsite

In this work Laponite was combined with a modified abundant natural polymer, (caboxymethyl cellulose), acrylic sodium salt polymer and lithium perchlorate aiming to produce inexpensive and sustainable nanocomposite electrolytes for functional electrochemical devices. Optical, electrochemical, structural, morphological and rheological characterization was performed in order to evaluate their properties and potential advantages as electrolyte. It was verified that the addition of Laponite led to an ionic conductivity at room temperature (25 C) in the range of 6 to 9 × 10- 5 Scm - 1 this value being then determined by the composition of the nanocomposite. These electrolytes were applied to electrochromic devices using evaporated nickel oxide thin film as the electrochromic layer. The devices exhibited a significant transmittance modulation that exceeds 45 % at 600 nm. © 2013 Elsevier B.V.

Sava, B. A. a, M. a Elisa, L. b Boroica, and R. C. C. c Monteiro. "Preparation method and thermal properties of samarium and europium-doped alumino-phosphate glasses." Materials Science and Engineering B: Solid-State Materials for Advanced Technology. 178 (2013): 1429-1435. AbstractWebsite

The present work investigates alumino-phosphate glasses from Li 2O-BaO-Al2O3-La2O3-P 2O5 system containing Sm3+ and Eu3+ ions, prepared by two different ways: a wet raw materials mixing route followed by evaporation and melt-quenching, and by remelting of shards. The linear thermal expansion coefficient measured by dilatometry is identical for both rare-earth-doped phosphate glasses. Comparatively to undoped phosphate glass the linear thermal expansion coefficient increases with 2 × 10-7 K-1 when dopants are added. The characteristic temperatures very slowly decrease but can be considered constant with atomic weight, atomic number and f electrons number of the doping ions in the case of Tg (vitreous transition temperature) and Tsr (high annealing temperature) but slowly increase in the case of Tir (low annealing temperature-strain point) and very slowly increase, being practically constant in the case of TD (dilatometric softening temperature). Comparatively to undoped phosphate glass the characteristic temperatures of Sm and Eu-doped glasses present lower values. The higher values of electrical conductance for both doped glasses, comparatively to usual soda-lime-silicate glass, indicate a slightly reduced stability against water. The viscosity measurements, showed a quasi-linear variation with temperature the mean square deviation (R 2) being ranged between 0.872% and 0.996%. The viscosity of doped glasses comparatively to the undoped one is lower at the same temperature. Thermogravimetric analysis did not show notable mass change for any of doped samples. DSC curves for both rare-earth-doped phosphate glasses, as bulk and powdered samples, showed Tg values in the range 435-450 C. Bulk samples exhibited a very weak exothermic peak at about 685 C, while powdered samples showed two weak exothermic peaks at about 555 C and 685 C due to devitrification of the glasses. Using designed melting and annealing programs, the doped glasses were improved regarding bubbles and cords content and strain elimination. © 2013 Elsevier B.V. All rights reserved.

Maneira, António, and João Correia de Freitas. "Projetos de v{\'ıdeos interativos no ensino superior: multimédia semântico e a aprendizagem." III Colóquio Luso-Brasileiro de Educação a Distância e Elearning. http://lead.uab.pt/OCS/index.php/CLB/club/paper/view/173, 2013. Abstract
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Maiti, Biplab K., Teresa Avilés, Marta S. P. Carepo, Isabel Moura, Sofia R. Pauleta, and José J. G. Moura. "Rearrangement of Mo-Cu-S Cluster Reflects the Structural ­Instability of Orange Protein Cofactor." Zeitschrift für anorganische und allgemeine Chemie. 639 (2013): 1361-1364. AbstractWebsite
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Martins, R.F.P.a, Ahnood Correia Pereira Barros Barquinha Costa Ferreira Nathan Fortunato A. b N. a. "Recyclable, flexible, low-power oxide electronics." Advanced Functional Materials. 23 (2013): 2153-2161. AbstractWebsite

The ability to process and dimensionally scale field-effect transistors with and on paper and to integrate them as a core component for low-power-consumption analog and digital circuits is demonstrated. Low-temperature-processed p- and n-channel integrated oxide thin-film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low-cost, recyclable paper substrates. The possibility of building these circuits using low-temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low-power circuitry with a recyclable substrate is an important step towards greener electronics. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Szabo, Csilla I., Pedro Amaro, Mauro Guerra, Sophie Schlesser, Alexander Gumberidze, Jose Paulo Santos, and Paul Indelicato. "Reference free, high-precision measurements of transition energies in few electron argon ions." AIP APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY: Twenty-Second International Conference. 1525 (2013): 68-72. AbstractWebsite

The use of a vacuum double crystal spectrometer, coupled to an electron-cyclotron resonance ion source (ECRIS), allows to measure low-energy x-ray transitions energies in highly-charged ions with accuracies of the order of a few parts per million. We have used this installation to measure the 1s2p 1 P1 - 1s2 1 S0 diagram line and the 1s2s 3 S1 - 1s2 1 S0 forbidden M1 transition energies in helium-like argon, the 1s2s2p 2 P j 1s2 2s 2 S1/2 transitions in lithium-like argon and the 1s2s2 2p 1 P1 - 1s2 2s2 1 S0 transition in beryllium-like argon. These transition measurements have accuracies between 2 and 4 ppm depending on the line intensity. Thanks to the excellent agreement between the simulations and the measurements, we were also able to measure the transition width of all the allowed transitions. The results are compared to recent QED and relativistic many-body calculations.

Szabo, Csilla I., Pedro Amaro, Mauro Guerra, Sophie Schlesser, Alexander Gumberidze, Jose Paulo Santos, and Paul Indelicato. "Reference free, high-precision measurements of transition energies in few electron argon ions." AIP Conf. Proc.. 1525 (2013): 68-72. AbstractWebsite

The use of a vacuum double crystal spectrometer, coupled to an electron-cyclotron resonance ion source (ECRIS), allows to measure low-energy x-ray transitions energies in highly-charged ions with accuracies of the order of a few parts per million. We have used this installation to measure the 1s2p 1 P1 - 1s2 1 S0 diagram line and the 1s2s 3 S1 - 1s2 1 S0 forbidden M1 transition energies in helium-like argon, the 1s2s2p 2 P j 1s2 2s 2 S1/2 transitions in lithium-like argon and the 1s2s2 2p 1 P1 - 1s2 2s2 1 S0 transition in beryllium-like argon. These transition measurements have accuracies between 2 and 4 ppm depending on the line intensity. Thanks to the excellent agreement between the simulations and the measurements, we were also able to measure the transition width of all the allowed transitions. The results are compared to recent QED and relativistic many-body calculations.

Silva, Teresa Pereira, Ondina M. Figueiredo, Daniel PS Oliveira, João Pedro Veiga, and Maria João Batista. "Rhenium incorporation in molybdenite: first results of a XANES study." 2nd Meeting of Synchrotron Radiation Users from Portugal and ESRF-Day. 2013. Abstract
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Aguiar, F. C., J. O. Cerdeira, M. J. Martins, and M. T. Ferreira. "Riparian forests of Southwest Europe: Are functional trait and species composition assemblages constrained by environment?" Journal of Vegetation Science. 24 (2013): 628-638. Abstract
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Araújo, A.a, Barros Mateus Gaspar Neves Vicente Filonovich Barquinha Fortunato Ferraria Botelho Do Rego Bicho Águas Martins R. a T. a. "Role of a disperse carbon interlayer on the performances of tandem a-Si solar cells." Science and Technology of Advanced Materials. 14 (2013). AbstractWebsite

We report the effect of a disperse carbon interlayer between the n-a-Si:H layer and an aluminium zinc oxide (AZO) back contact on the performance of amorphous silicon solar cells. Carbon was incorporated to the AZO film as revealed by x-ray photoelectron spectroscopy and energy-dispersive x-ray analysis. Solar cells fabricated on glass substrates using AZO in the back contact performed better when a disperse carbon interlayer was present in their structure. They exhibited an initial efficiency of 11%, open-circuit voltage Voc = 1.6 V, short-circuit current JSC = 11 mA cm -2 and a filling factor of 63%, that is, a 10% increase in the J SC and 20% increase in the efficiency compared to a standard solar cell. © 2013 National Institute for Materials Science.

Araújo, Andreia, Raquel Barros, Tiago Mateus, Diana Gaspar, Nuno Neves, António Vicente, Sergej A. Filonovich, Pedro Barquinha, Elvira Fortunato, Ana M. Ferraria, and others. "Role of a disperse carbon interlayer on the performances of tandem a-Si solar cells." Science and Technology of Advanced Materials. 14 (2013): 045009. Abstract
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Figueiredo, Ondina M., Teresa Pereira Silva, Maria João Batista, Daniel PS Oliveira, and João Pedro Veiga. "Scarce industrial commodities: a glance at the possible rhenium availability in mining residues from the exploitation of Portuguese ore deposits." Materials 2013: International Conference. 2013. Abstract
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Dos Santos, F. P. A., C. Cismaşiu, and J. Pamies Teixeira. "Semi-active vibration control device based on superelastic NiTi wires." Structural Control and Health Monitoring. 20 (2013): 890-902. AbstractWebsite
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Ercin, G. H., P. P. Camanho, J. Xavier, G. Catalanotti, S. Mahdi, and P. Linde. "Size effects on the tensile and compressive failure of notched composite laminates." Composite Structures. 96 (2013): 736-744. Abstract
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Viegas, Aldino, Joao Sardinha, Filipe Freire, Daniel F. Duarte, Ana L. Carvalho, Carlos M. G. A. Fontes, Maria J. Romao, Anjos L. Macedo, and Eurico J. Cabrita. "Solution structure, dynamics and binding studies of a family 11 carbohydrate-binding module from Clostridium thermocellum (CtCBM11)." The Biochemical journal. 451 (2013): 289-300.Website
Galesio, M., H. López-Fdez, M. Reboiro-Jato, S. Gómez-Meire, D. Glez-Peña, F. Fdez-Riverola, C. Lodeiro, M. E. Diniz, and J. L. Capelo. "Speeding up the screening of steroids in urine: Development of a user-friendly library." Steroids. 78 (2013): 1226-1232. AbstractWebsite
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Ferreira, I.a, Baptista Leitão Soares Fortunato Martins Borges A. C. a J. "Strongly photosensitive and fluorescent F8T2 electrospun fibers." Macromolecular Materials and Engineering. 298 (2013): 174-180. AbstractWebsite

Electrospun fibers of poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2) with exceptional electro-optical performance are obtained. The I/T characteristics measured in fibers with 7-15 μm diameter and 1 mm length show a semiconductor behavior; their thermal activation energy is 0.5 eV and the dark conductivity at RT is 5 × 10-9 (Ω cm)-1. Besides exhibiting a photosensitivity of about 60 under white light illumination with a light power intensity of 25 mW · cm-2, the fibers also attain RT photoluminescence in the cyan, yellow, and red wavelength range under ultraviolet, blue, and green light excitation, respectively. Optical microscope images of F8T2 reveal homogeneous electrospun fibers, which are in good agreement with the uniformly radial fluorescence observed. The production of electrospun fibers from poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2) obtained without a carrier polymer is reported. The obtained fibers are shown to have properties suitable for organic fiber photovoltaic and sensors applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Palma, Angelina S., Benedita Pinheiro, Yan Liu, Yoichi Takeda, Wengang Chai, Yukishige Ito, Maria Joao Romao, Ana Luisa Carvalho, and Ten Feizi. "The Structural Basis of the Recognition of Di-glucosylated N-glycans by the ER Lectin Malectin." Glycobiology. 23 (2013): 1368-1369. Abstract
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Fernandes, Susete N., Yong Geng, Silvia Vignolini, Beverley J. Glover, Ana C. Trindade, João P. Canejo, Pedro L. Almeida, Pedro Brogueira, and Maria H. Godinho. "Structural color and iridescence in transparent sheared cellulosic films." Macromolecular Chemistry and Physics. 214.1 (2013): 25-32. Abstract
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Neu, Ursula, Stacy-Ann A. Allen, Barbel S. Blaum, Yan Liu, Martin Frank, Angelina S. Palma, Luisa J. Stroh, Ten Feizi, Thomas Peters, Walter J. Atwood, and Thilo Stehle. "A Structure-Guided Mutation in the Major Capsid Protein Retargets BK Polyomavirus." PLoS pathogens. 9 (2013): e1003688. Abstract
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Neu, Ursula, Zaigham Mahmood Khan, Benjamin Schuch, Angelina S. Palma, Yan Liu, Michael Pawlita, Ten Feizi, and Thilo Stehle. "Structures of B-Lymphotropic Polyomavirus VP1 in Complex with Oligosaccharide Ligands." PLoS pathogens. 9 (2013): e1003714. Abstract
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Alves, R.D.a, Rodrigues Andrade Pawlicka Pereira Martins Fortunato Silva L. C. a J. "Study and characterization of a novel polymer electrolyte based on agar doped with magnesium triflate." Molecular Crystals and Liquid Crystals. 570 (2013): 1-11. AbstractWebsite

In the present work one host natural matrix - agar - has been doped with magnesium triflate (Mg(CF3SO3)2) with the goal of developing electrolytes for the fabrication of solid-state devices. The resulting samples have been represented by the notation Agar nMg(CF3SO3)2, where n represents the percentage of the magnesium triflate salt proportion in the electrolyte samples. The samples investigated, with n between 0.00% and 37.56%, have been obtained as transparent and thin films. The samples have been characterized by conductivity measurements, thermal analysis, cyclic voltammetry, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The agar-based electrolytes were also tested as ionic conductor in an electrochromic device with the following configuration: glass/indium tin oxide (ITO)/WO 3/agar-based electrolyte/CeO2-TiO2/ITO/glass. © 2013 Copyright Taylor and Francis Group, LLC.

Valtchev, Stanimir. "Study of a single-phase series active power filter with hysteresis control." Journal of Energy and Power Engineering (2013). Abstract
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