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2010
Smith, A., R. Araújo, and O. Mateus. "A plesiosauroid skull from the Toarcian (Lower Jurassic) of Alhadas, Portugal." 70th Annual Meeting of the Society of Vertebrate Paleontology. Journal of Vertebrate Paleontology. Pittsburgh, Pennsylvania, USA 2010. 166A. Abstractsmith_araujo__mateus_2010_plesiosauroid_skull_toarcian_jurassic_alhadas_portugal_svp10abstracts.pdf

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by Cismasiu, Edited Corneliu Shape Memory Alloys. Scyio, 2010.Website
Pereira, P., M. H. Fino, and M. Ventim-Neves. "Automatic generation of RF integrated inductors analytical characterization." Symbolic and Numerical Methods, Modeling and Applications to Circuit Design (SM2ACD), 2010 XIth International Workshop on. 2010. 1-4. Abstract

This paper addresses the automatic generation of RF integrated inductors model. In this work the double p-model is used as a way of characterizing the inductor behaviour over a frequency range beyond the self-resonant value. For the evaluation of the model element values analytical expressions based on technology parameters as well as on the device geometric characteristics are used. The use of a technology-based methodology for the evaluation of the model parameters grants the adaptability of the models generated to any technology. The inductor analytical characterization is integrated into an optimization-based tool for the automatic design of RF integrated inductors. This tool uses a Genetic Algorithm (GA) optimization procedure, where user defined constraints on the design parameters are taken into account. Due to the design constraints nature and topology constraints, discrete variables optimization techniques are used.

Rosa, V., C. I. M. Santos, R. Welter, G. Aullon, C. Lodeiro, and T. Aviles. "Comparison of the Structure and Stability of New alpha-Diimine Complexes of Copper(I) and Silver(I): Density Functional Theory versus Experimental." Inorg Chem. 49 (2010): 8699-8708. AbstractWebsite

New compounds of the general formulas [M(Ar-BIAN)(2)]BF(4) and [M(Ar-BIAN)(NCMe)(2)]BF(4), where M=Cu(1) or Ag(1) and Ar-BIAN = bis(aryl)acenaphthenequinonediimine, were synthesized by the direct reaction of [Cu(NCMe)(4)]BF(4) or [Ag(NCMe)(4)]BF(4) with the corresponding Ar-BIAN ligand in dried CH(2)Cl(2). The synthesized compounds are [M(o, d, p-Me(3)C(6)H(2)-BIAN)(2)]BF(4) where M = Cu(1) (1) and Ag(1) (2), [M(o,d-iPr(2)C(6)H(3)-BIAN)(NCMe)(2)]BF(4) where M = Cu(1) (3) and Ag(1) (4), and [Ag(o,d-iPr(2)C(6)H(3)-BIAN)(2)]BF(4) (5). The crystal structures of compounds 1-3 and 5 were solved by singlecrystal X-ray diffraction. In all cases copper(I) or silver(I) are in a distorted tetrahedron that is constructed from the four nitrogen atoms of the two a-diimine ligands or, in 3, from one a-diimine ligand and two acetonitrile molecules. All compounds were characterized by elemental analyses, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, and IR, UV-vis, and (1)H NMR spectroscopy. The analysis of the molecular geometry and the energetic changes for the formation reactions of the complexes, in a CH(2)Cl(2) solution, were evaluated by density functional theory calculations and compared with the experimental results.

Martins, R. M. S., N. Schell, H. Reuther, L. Pereira, K. K. Mahesh, R. J. C. Silva, and F. M. Braz Fernandes. "Texture development, microstructure and phase transformation characteristics of sputtered Ni-Ti Shape Memory Alloy films grown on TiN < 111 >." Thin Solid Films. 519.1 (2010): 122-128. Abstract
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Barquinha, Pedro, Luis Pereira, Goncalo Goncalves, Danjela Kuscer, Marija Kosec, Anna Vila, Antonis Olziersky, Juan Ramon Morante, Rodrigo Martins, and Elvira Fortunato. "Low-temperature sputtered mixtures of high-kappa and high bandgap dielectrics for GIZO TFTs." Journal of the Society for Information Display. 18 (2010): 762-772. AbstractWebsite
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Martins, R. M. S., N. Schell, H. Reuther, L. Pereira, K. K. Mahesh, R. J. C. Silva, and Braz F. M. Fernandes. "{Texture development, microstructure and phase transformation characteristics of sputtered Ni–Ti Shape Memory Alloy films grown on TiN<111>}." Thin Solid Films. 519 (2010): 122-128. AbstractWebsite
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Moniz, António, and José Miquel Cabeças. "Editorial Note." Enterprise and Work Innovation Studies. 6 (2010): 7-8. AbstractWebsite

No abstract is available for this item.

Nayak, Pradipta K., Tito Busani, Elangovan Elamurugu, Pedro Barquinha, Rodrigo Martins, Yongtaek Hong, and Elvira Fortunato. "Zinc concentration dependence study of solution processed amorphous indium gallium zinc oxide thin film transistors using high-k dielectric." Applied Physics Letters. 97 (2010). AbstractWebsite
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Silveira, Celia M., Sofia P. Gomes, Alberto N. Araujo, Conceicao M. B. S. M. Montenegro, Smilja Todorovic, Ana S. Viana, Rui JC Silva, Jose J. G. Moura, and Gabriela M. Almeida. "An efficient non-mediated amperometric biosensor for nitrite determination." Biosensors & Bioelectronics. 25.9 (2010): 2026-2032. Abstract
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Fortunato, Elvira, Vitor Figueiredo, Pedro Barquinha, Elangovan Elamurugu, Raquel Barros, Goncalo Goncalves, Sang-Hee Ko Park, Chi-Sun Hwang, and Rodrigo Martins. "Thin-film transistors based on p-type Cu2O thin films produced at room temperature." Applied Physics Letters. 96 (2010). AbstractWebsite
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Martins, R. M. S., N. Schell, J. von Borany, K. K. Mahesh, R. J. C. Silva, and F. M. Braz Fernandes. "Structural evolution of magnetron sputtered shape memory alloy Ni-Ti films." Vacuum. 84.7 (2010): 913-919. Abstract
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Figueiredo, Elin, Rui JC Silva, Fatima M. Araujo, and Joao C. Senna-Martinez. "Identification of ancient gilding technology and Late Bronze Age metallurgy by EDXRF, Micro-EDXRF, SEM-EDS and metallographic techniques." Microchimica Acta. 168.3-4 (2010): 283-291. Abstract
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Barbosa, Paulo E. S., Anikó Costa, Lu\'ıs Gomes, Franklin Ramalho, Jorge Figueiredo, and Antônio Junior. "{A MDA-based Contribution for Integrating Web Services within Embedded System's Design}." 8{\textsuperscript{th}} IEEE International Conference on Industrial Informatics (INDIN 2010). 2010. Abstract
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Fortunato, Elvira, Vitor Figueiredo, Pedro Barquinha, Elangovan Elamurugu, Raquel Barros, Goncalo Goncalves, Sang-Hee Ko Park, Chi-Sun Hwang, and Rodrigo Martins. "Thin-film transistors based on p-type Cu2O thin films produced at room temperature (vol 96, 192102, 2010)." Applied Physics Letters. 96 (2010). AbstractWebsite
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Botas, Jose D., Alexandre Velhinho, and Rui JC Silva. "A theoretical approach to the elastic behaviour of compact and hollow spherical particles reinforced metal-matrix composites." International Journal of Materials Research. 101.6 (2010): 752-757. Abstract
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Lavareda, G., P. Parreira, J. Valente, F. T. Nunes, A. Amaral, and C. Nunes de Carvalho. "Highly transparent undoped semiconducting ZnOx thin films deposited at room temperature by rf-PERTE - Influence of rf power." JOURNAL OF NON-CRYSTALLINE SOLIDS. 356 (2010): 1392-1394. Abstract

Transparent, undoped semiconductive thin films of zinc oxide were deposited by radio frequency plasma enhanced reactive thermal evaporation of zinc rods in the presence of oxygen at room temperature, without any post-deposition annealing treatments. The study of the variation of rf power, in the range 5-200W, on the main properties of these films was made. A decrease of the electrical conductivity of these films with increasing rf power was observed (10(-3) to 10(-12) (Omega cm)(-1)), respectively, while the average visible transparency was kept practically constant (approximate to 80%). From this initial study, a set of bottom-gate type thin-film transistors were made using the most promising semiconductor materials. Preliminary I(V) measurements showed all transistors working, with best results obtained from zinc oxide material deposited at the lowest rf power (20 W), within the deposition conditions range which leads to semiconductive material. Such devices presented an I-on (20 V)/I-off (-5 V) ratio of 6 x 10(6) and a field-effect mobility of 0.37 cm(2)/(V s). (C) 2010 Elsevier B.V. All rights reserved.

Lavareda, G., P. Parreira, J. Valente, F. T. Nunes, A. Amaral, and C. Nunes de Carvalho. "Highly transparent undoped semiconducting ZnOx thin films deposited at room temperature by rf-PERTE - Influence of rf power." JOURNAL OF NON-CRYSTALLINE SOLIDS. 356 (2010): 1392-1394. Abstract

Transparent, undoped semiconductive thin films of zinc oxide were deposited by radio frequency plasma enhanced reactive thermal evaporation of zinc rods in the presence of oxygen at room temperature, without any post-deposition annealing treatments. The study of the variation of rf power, in the range 5-200W, on the main properties of these films was made. A decrease of the electrical conductivity of these films with increasing rf power was observed (10(-3) to 10(-12) (Omega cm)(-1)), respectively, while the average visible transparency was kept practically constant (approximate to 80%). From this initial study, a set of bottom-gate type thin-film transistors were made using the most promising semiconductor materials. Preliminary I(V) measurements showed all transistors working, with best results obtained from zinc oxide material deposited at the lowest rf power (20 W), within the deposition conditions range which leads to semiconductive material. Such devices presented an I-on (20 V)/I-off (-5 V) ratio of 6 x 10(6) and a field-effect mobility of 0.37 cm(2)/(V s). (C) 2010 Elsevier B.V. All rights reserved.

Najmudin, S., S. R. Pauleta, I. Moura, and MJ Romao. "The 1.4 angstrom resolution structure of Paracoccus pantotrophus pseudoazurin." Acta Crystallographica Section F-Structural Biology and Crystallization Communications. 66 (2010): 627-635. AbstractWebsite

Pseudoazurins are small type 1 copper proteins that are involved in the flow of electrons between various electron donors and acceptors in the bacterial periplasm, mostly under denitrifying conditions. The previously determined structure of Paracoccus pantotrophus pseudoazurin in the oxidized form was improved to a nominal resolution of 1.4 angstrom, with R and R-free values of 0.188 and 0.206, respectively. This high-resolution structure makes it possible to analyze the interactions between the monomers and the solvent structure in detail. Analysis of the high-resolution structure revealed the structural regions that are responsible for monomer-monomer recognition during dimer formation and for protein-protein interaction and that are important for partner recognition. The pseudoazurin structure was compared with other structures of various type 1 copper proteins and these were grouped into families according to similarities in their secondary structure; this may be useful in the annotation of copper proteins in newly sequenced genomes and in the identification of novel copper proteins.

Costa, J., M. Fernandes, M. Vieira, G. Lavareda, CN Carvalho, and A. Karmali. "Field Effect and Light-Assisted a-Si:H Sensors for Detection of Ions in Solution." SENSOR LETTERS. 8 (2010): 493-496. Abstract

In this paper we present an amorphous silicon device that can be used in two operation modes to measure the concentration of ions in solution. While crystalline devices present a higher sensitivity, their amorphous counterpart present a much lower fabrication cost, thus enabling the production of cheap disposable sensors for use, for example, in the food industry. The devices were fabricated on glass substrates by the PECVD technique in the top gate configuration, where the metallic gate is replaced by an electrolytic solution with an immersed Ag/AgCl reference electrode. Silicon nitride is used as gate dielectric enhancing the sensitivity and passivation layer used to avoid leakage and electrochemical reactions. In this article we report on the semiconductor unit, showing that the device can be operated in a light-assisted mode, where changes in the pH produce changes on the measured ac photocurrent. In alternative the device can be operated as a conventional ion selective field effect device where changes in the pH induce changes in the transistor's threshold voltage.

Costa, J., M. Fernandes, M. Vieira, G. Lavareda, CN Carvalho, and A. Karmali. "Field Effect and Light-Assisted a-Si:H Sensors for Detection of Ions in Solution." SENSOR LETTERS. 8 (2010): 493-496. Abstract

In this paper we present an amorphous silicon device that can be used in two operation modes to measure the concentration of ions in solution. While crystalline devices present a higher sensitivity, their amorphous counterpart present a much lower fabrication cost, thus enabling the production of cheap disposable sensors for use, for example, in the food industry. The devices were fabricated on glass substrates by the PECVD technique in the top gate configuration, where the metallic gate is replaced by an electrolytic solution with an immersed Ag/AgCl reference electrode. Silicon nitride is used as gate dielectric enhancing the sensitivity and passivation layer used to avoid leakage and electrochemical reactions. In this article we report on the semiconductor unit, showing that the device can be operated in a light-assisted mode, where changes in the pH produce changes on the measured ac photocurrent. In alternative the device can be operated as a conventional ion selective field effect device where changes in the pH induce changes in the transistor's threshold voltage.

O'Brien, Shane, Mark G. Nolan, Mehmet \c{C}opuroglu, Jeff A. Hamilton, Ian Povey, Luis Pereira, Rodrigo Martins, Elvira Fortunato, and Martyn Pemble. "{Zinc oxide thin films: Characterization and potential applications}." Thin Solid Films. 518 (2010): 4515-4519. AbstractWebsite
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Valtchev, Stanimir, and Jorge Pamies Teixeira. "The Charging of Hybrid and Electrical Vehicles? Batteries: Contactless Energy Transfer as the key to the future." 2010 International Symposium on Electric Vehicle and 2-nd Annual Conference of Polish Society for Environment Friendly Vehicles. 2010. Abstract
Would it be necessary to charge rapidly the electric vehicle (EV) and hybrid electric vehicle (HEV)? It is not easy to answer without a thorough look at the capability of the modern propulsion battery and the power necessities of the EV and HEV. The different possible solutions are compared and maximum speed of charging is analysed. The wired connection for charging is compared to the wireless energy transfer and because of the limitations imposed by the modern and future batteries, the contactless energy transfer is chosen as the future charging method.
Valtchev, Stanimir, and Svilen Valtchev. "Improved strategy for an instantaneous super-resonant converter regulation." 12th International Conference on Optimization of Electrical and Electronic Equipment (OPTIM). 2010. 631-638. Abstract
The proposed regulation strategy consists in obtaining at the right time the correct information about the energy contained in the resonant tank. This information allows a stable operation of the switches and a higher efficiency of any Series Loaded Series Resonant (SLSR) power converter, especially when contactless energy transfer is concerned. The strategy is based on guaranteeing the correct portion of energy transported by the resonant tank to the load. The portion has to vary corresponding to the error signal taken from the output voltage and remains unchanged if the error signal is at its minimum. In a certain way this method is similar to the Current Mode Control of the classical power converters. The viability of the idea is demonstrated by simulation of a realistic analogue circuit (on preparation for a digital implementation in the near future).
Teixeira, Jorge Pamies, and Stanimir Valtchev. "An Insight to Potential Actions Facing Future Needs of Electric and Hybrid Electric Vehicles." 2010 International Symposium on Electric Vehicle and 2-nd Annual Conference of Polish Society for Environment Friendly Vehicles. 2010. Abstract
Recent issues of global heating and energy shortages are imposing a need to change our paradigm around transportation. Somehow, electric vehicles are progressively standing as a strong and necessary alternative for the society. Technically and technologically the acceptance of the EV is easier now than ever but the psychology of the consumers and the running business of internal combustion vehicles, the whole existing infrastructure are too much conservative to be changed easily. The changes in technology require changes in the engineering society and its human resources. The objective of this paper is to give a contribution to the discussion and reflection of potential future scenarios where EV?HEV?s are spread across the society. It gives an overview of the range of knowledge and competences necessary for a sustainable and streamlined development of those. In fact, it is expected that a new kind of professional profiles need to be created or developed to supply the work market with the right human resources. The paper provides some discussion on the creation of new profiles or adaption of existing ones. Among different possible scenarios the creation of post-graduation courses for students holding undergraduate profiles in the fields referred to earlier would be an interesting and viable solution for fast response. The post graduation would be focused in specific key areas of the EV?HEV. Several factors are pointed out to endorse this scenario