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2007
Albarran, T., Lopes Cabeça Martins Mourão L. J. R. "Preliminary budget methodology for reverse engineering applications using laser scanning." Proceedings of the 3rd International Conference on Advanced Research in Virtual and Rapid Prototyping: Virtual and Rapid Manufacturing Advanced Research Virtual and Rapid Prototyping. 2007. 231-235. Abstract

The driving force behind the work herein presented is the importance of budgeting in a competitive market. The problem at hands is the creation of a budgeting methodology for reverse engineering applications, involving laser scanning, that has the ability to generate budgets for different customer accuracy requirements and for parts of different morphologic characteristics, such as: shape, dimension and/or detail complexity. A breakup approach was used to implement the methodology: the reverse engineering process was broken in nine basic identified steps and elementary sources of cost were defined at the different reverse engineering stages as well. Particular budgeting methodologies for each step of the process were created. The obtained results so far point to the possibility of creating a complete budgeting system based on the proposed methodology. © 2008 Taylor & Francis Group.

Elangovan, E., Marques Fernandes Martins Fortunato A. F. M. B. "Preliminary studies on molybdenum-doped indium oxide thin films deposited by radio-frequency magnetron sputtering at room temperature." Thin Solid Films. 515 (2007): 5512-5518. AbstractWebsite

Thin films of molybdenum-doped indium oxide (IMO) were prepared by a 3-source, cylindrical radio-frequency magnetron sputtering at room temperature. The films were post-annealed and were characterized by their structural (X-ray diffraction) and optical (UV-VIS-NIR spectrophotometer) properties. The films were studied as a function of oxygen volume percentage (O2 vol.%) ranging from 3.5 to 17.5. The structural studies revealed that the as-deposited amorphous films become crystalline on annealing. In most cases, the (222) reflection emerged as high intensive peak. The poor visible transmittance of the films as-deposited without oxygen was increased from ∼ 12% to over 80% on introducing oxygen (3.5 O2 vol.%). For the films annealed in open air, the average visible transmittance in the wavelength ranging 400-800 nm was varied between 77 and 84%. The films annealed at high temperatures (> 300 °C) decreased the transmittance to as low as < 1%. The optical band gap of the as-deposited films increased from the range 3.83-3.90 to 3.85-3.98 eV on annealing at different conditions. © 2007 Elsevier B.V. All rights reserved.

Ferreira, I. M. P. L. V., O. Pinho, M. V. Mota, P. Tavares, A. Pereira, M. P. Goncalves, D. Torres, C. Rocha, and J. A. Teixeira. "Preparation of ingredients containing an ACE-inhibitory peptide by tryptic hydrolysis of whey protein concentrates." International Dairy Journal. 17 (2007): 481-487. AbstractWebsite

This study describes the characterisation of whey protein hydrolysates obtained from tryptic hydrolysis to assess their application as ingredients with angiotensin-converting-enzyme (ACE) inhibitory action. The levels of a-lactalbumin (alpha-la) and P-lactoglobulin (beta-lg) remaining after hydrolysis were quantified. Peptides were separated by RP-HPLC, and Ala-Leu-Pro-Met-His-Ile-Arg (ALPMHIR), the most potent beta-lg-derived ACE-inhibitory peptide was monitored. A correlation curve was established for the production of this peptide as a function of hydrolysis time. Heat-induced gelation of hydrolysates was studied by small-deformation rheology. The gelation times and the strength of the final gels were highly dependent on the degree of hydrolysis. Smaller peptides liberated by hydrolysis contributed to the inability of whey protein hydrolysates to gel. (c) 2006 Elsevier Ltd. All rights reserved.

Chilibon, I., C. Dias, P. Inacio, and J. Marat-Mendes. "PZT and PVDF bimorph actuators." Journal of Optoelectronics and Advanced Materials. 9 (2007): 1939-1943. Abstract
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Indelicato, P., J. P. Santos, S. Boucard, and J. P. Descalux. "QED and relativistic corrections in superheavy elements." The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics. 45 (2007): 155-170. AbstractWebsite
In this paper we review the different relativistic and QED contributions to energies, ionic radii, transition probabilities and Landé g-factors in super-heavy elements, with the help of the MultiConfiguration Dirac-Fock method (MCDF). The effects of taking into account the Breit interaction to all orders by including it in the self-consistent field process are demonstrated. State of the art radiative corrections are included in the calculation and discussed. We also study the non-relativistic limit of MCDF calculation and find that the non-relativistic offset can be unexpectedly large.
Indelicato, P., J. P. Santos, S. Boucard, and J. P. Descalux. "QED and relativistic corrections in superheavy elements." The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics. 45 (2007): 155-170. AbstractWebsite

In this paper we review the different relativistic and QED contributions to energies, ionic radii, transition probabilities and Landé g-factors in super-heavy elements, with the help of the MultiConfiguration Dirac-Fock method (MCDF). The effects of taking into account the Breit interaction to all orders by including it in the self-consistent field process are demonstrated. State of the art radiative corrections are included in the calculation and discussed. We also study the non-relativistic limit of MCDF calculation and find that the non-relativistic offset can be unexpectedly large.Topical Issue on the Atomic Properties of the Heaviest Elements

Alferes, {José Júlio}, and Ricardo Amador. "r3- A foundational ontology for reactive rules." On the Move to Meaningful Internet Systems 2007: CoopIS, DOA, ODBASE, GADA, and IS - OTM Confederated International Conferences CoopIS, DOA, ODBASE, GADA, and IS 2007, Proceedings. PART 1 ed. Vol. 4803 LNCS. Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 4803 LNCS. 2007. 933-952. Abstract
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Alves, A., AJL Phillips, I. Henriques, and A. Correia. "Rapid differentiation of species of Botryosphaeriaceae by PCR fingerprinting." Research in Microbiology. 158 (2007): 112-121. Abstract
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Martins, C. E., AS Pereira, P. Tavares, C. M. Cordas, F. Folgosa, C. G. Timoteo, S. G. Naik, and BH HUYNH. "Redox states of Nitric Oxide Reductase from Pseudomonas nautica: Kinetic and Spectroscopic characterization." J Biol Inorg Chem. 12 (2007): S83. Abstract
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Araújo, J., and J. D. Mitchell. "Relative ranks in the monoid of endomorphisms of an independence algebra." Monatsh. Math.. 151 (2007): 1-10. AbstractWebsite
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Costa, A. M., M. C. Martins, J. P. Santos, P. Indelicato, and F. Parente. "Relativistic calculation of Kα hypersatellite line energies and transition probabilities for selected atoms with 12<=Z<=80." Journal of Physics B: Atomic, Molecular and Optical Physics. 40 (2007): 57. AbstractWebsite
The transition probabilities of Kα hypersatellite lines and energy shifts with respect to the corresponding diagram lines are computed using the Dirac–Fock model for several values of atomic number Z throughout the periodic table. The influence of the Breit interaction on the Kα1h/Kα2h line intensity ratio, Kα1h and Kα2h line energy shifts and Kα1h to Kα2h line energy splitting is evaluated. Double-K shell hole threshold values for selected elements with 23 ⩽Z⩽ 30, calculated within the same approach, are compared with available experimental results.
Costa, A. M., M. C. Martins, J. P. Santos, P. Indelicato, and F. Parente. "Relativistic calculation of K&alpha; hypersatellite line energies and transition probabilities for selected atoms with 12 ≤ Z ≤ 80." Journal of Physics B: Atomic, Molecular and Optical Physics. 40 (2007): 57. AbstractWebsite

The transition probabilities of K&alpha; hypersatellite lines and energy shifts with respect to the corresponding diagram lines are computed using the Dirac&ndash;Fock model for several values of atomic number <I>Z</I> throughout the periodic table. The influence of the Breit interaction on the K&alpha;<SUB>1</SUB><SUP>h</SUP>/K&alpha;<SUB>2</SUB><SUP>h</SUP> line intensity ratio, K&alpha;<SUB>1</SUB><SUP>h</SUP> and K&alpha;<SUB>2</SUB><SUP>h</SUP> line energy shifts and K&alpha;<SUB>1</SUB><SUP>h</SUP> to K&alpha;<SUB>2</SUB><SUP>h</SUP> line energy splitting is evaluated. Double-K shell hole threshold values for selected elements with 23 &les;<I>Z</I>&les; 30, calculated within the same approach, are compared with available experimental results.

Gomes, L., F. Coito, A. Costa, L. Palma, and P. Almeida. "Remote laboratories support within teaching and learning activities." International Conference on Remote Engineering and Virtual Instrumentation (2007). Abstract
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Martins, R., P. Barquinha, L. Pereira, I. Ferreira, and E. Fortunato. "Role of order and disorder in covalent semiconductors and ionic oxides used to produce thin film transistors." Applied Physics A. 89.1 (2007): 37-42. Abstract
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Martins, R., Barquinha Pereira Ferreira Fortunato P. L. I. "Role of order and disorder in covalent semiconductors and ionic oxides used to produce thin film transistors." Applied Physics A: Materials Science and Processing. 89 (2007): 37-42. AbstractWebsite

This paper aims to discuss the effect of order and disorder on the electrical performances of covalent silicon semiconductors and ZnO based ionic oxide semiconductors used as active channel layers in thin film transistors. The effect of disorder on covalent semiconductors directly affects their electrical transport properties due to the asymmetric behaviour of sp states, while in ionic oxide semiconductors it is found that this effect is small due to the fact that angular disorder has no effect on the spherical symmetry of s states. To this we must add that the mobility of carriers in both systems is quite different, being also affected by electron-phonon interactions (weak in silicon and strong in ionic oxides leading to formation of polarons). Besides, the impurity doping effect and the presence of vacancies in disordered silicon and in ionic oxides behave differently, which will influence the thin film properties and so, the performances of the devices produced. © 2007 Springer-Verlag.

Martins, R., P. Barquinha, I. Ferreira, L. Pereira, G. GONCALVES, and E. Fortunato. "Role of order and disorder on the electronic performances of oxide semiconductor thin film transistors." Journal of applied physics. 101.4 (2007): 044505-7. Abstract
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Martins, R.b, Barquinha Ferreira Pereira Goņalves Fortunato P. a I. a. "Role of order and disorder on the electronic performances of oxide semiconductor thin film transistors." Journal of Applied Physics. 101 (2007). AbstractWebsite

The role of order and disorder on the electronic performances of n -type ionic oxides such as zinc oxide, gallium zinc oxide, and indium zinc oxide used as active (channel) or passive (drain/source) layers in thin film transistors (TFTs) processed at room temperature are discussed, taking as reference the known behavior observed in conventional covalent semiconductors such as silicon. The work performed shows that while in the oxide semiconductors the Fermi level can be pinned up within the conduction band, independent of the state of order, the same does not happen with silicon. Besides, in the oxide semiconductors the carrier mobility is not bandtail limited and so disorder does not affect so strongly the mobility as it happens in covalent semiconductors. The electrical properties of the oxide films (resistivity, carrier concentration, and mobility) are highly dependent on the oxygen vacancies (source of free carriers), which can be controlled by changing the oxygen partial pressure during the deposition process and/or by adding other metal ions to the matrix. In this case, we make the oxide matrix less sensitive to the presence of oxygen, widening the range of oxygen partial pressures that can be used and thus improving the process control of the film resistivity. The results obtained in fully transparent TFT using polycrystalline ZnO or amorphous indium zinc oxide (IZO) as channel layers and highly conductive poly/nanocrystalline ZGO films or amorphous IZO as drain/source layers show that both devices work in the enhancement mode, but the TFT with the highest electronic saturation mobility and on/off ratio 49.9 cm2 V s and 4.3× 108, respectively, are the ones in which the active and passive layers are amorphous. The ZnO TFT whose channel is based on polycrystalline ZnO, the mobility and on/off ratio are, respectively, 26 cm2 V s and 3× 106. This behavior is attributed to the fact that the electronic transport is governed by the s -like metal cation conduction bands, not significantly affected by any type of angular disorder promoted by the 2p O states related to the valence band, or small amounts of incorporated metal impurities that lead to a better control of vacancies and of the TFT off current. © 2007 American Institute of Physics.

Aguas, H., Pereira Costa Raniero Fortunato Martins L. D. L. "Role of the oxide layer on the performances of a-Si:H schottky structures applied to PDS fabrication." Materials Research Society Symposium Proceedings. Vol. 910. 2007. 415-420. Abstract

In this work we present results of studies performed on Schottky and metal-insulator-semiconductor (MIS) position sensitive detectors (PSD) structures: substrate (glass)/ Cr (300 nm) / a-Si:H [n] (37 nm) / a-Si:H [i] (600 nm) / SiO2 (1.5 nm - for the MIS) / Au (7 nm). The effect of the interfacial oxide layer between Au and a-Si:H, for the MIS structures, was studied and compared with the Schottky, in order to determine how beneficial it could be for device performances and time degradation. For doing so, the Au thickness of 70Å was deposited by thermal evaporation on an oxide free (Schottky) and oxidized (≈20Å) (MIS) a-Si:H surfaces. These structures were characterized by SIMS, RBS, SEM and AFM in order to correlate the obtained diffusion profile of Au at the interface and the topography with the presence of the oxide at the interface. The results show that the Au inter-diffuses very easily in the oxide free a-Si:H surface, even at room temperature, degrading the devices performance. On the other hand, the MIS structures, with their interfacial oxide present no structural changes after annealing and the PSD produced are stable. We believe that this effect is associated with the barrier effect of the interfacial oxide that prevents the Au diffusion. The optimized 1D MIS sensors are stable and exhibit a linearity error as low as 0.8 % and sensitivities of 33 mV/cm for a 5 mW spot beam intensity at a wavelength of 532 nm, while the Schottky sensors showed a time degradation of their characteristics. © 2006 Materials Research Society.

Castanhinha, R., and O. Mateus. "Short review on the marine reptiles of Portugal: ichthyosaurs, plesiosaurs and mosasaurs." Journal of Vertebrate Paleontology. 27(suppl. to 3) (2007): 57. Abstract
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Coito, F., L. Gomes, and A. Costa. "Simulation, emulation and remote experiments." Proceedings of the Workshop on using VR in Education, Lisboa (2007): 99-110. Abstract
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Kitsara, M., D. Goustouridis, S. Chatzandroulis, M. Chatzichristidi, I. Raptis, T. Ganetsos, R. Igreja, and C. J. Dias. "Single chip interdigitated electrode capacitive chemical sensor arrays." Sensors and Actuators B-Chemical. 127 (2007): 186-192. Abstract
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Kitsara, M., D. Goustouridis, S. Chatzandroulis, M. Chatzichristidi, I. Raptis, T. Ganetsos, R. Igreja, and C. J. Dias. "Single chip interdigitated electrode capacitive chemical sensor arrays." Sensors and Actuators B-Chemical. 127 (2007): 186-192. AbstractWebsite
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Kitsara, M., D. Goustouridis, S. Chatzandroulis, M. Chatzichristidi, I. Raptis, Th. Ganetsos, R. Igreja, and C. J. Dias. "Single chip interdigitated electrode capacitive chemical sensor arrays." Sensors and Actuators B-Chemical. 127 (2007): 186-192. Abstract
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Lanca, M. C., M. Fu, E. Neagu, L. A. Dissado, J. Marat-Mendes, A. Tzimas, and S. Zadeh. "Space charge analysis of electrotherinally aged XLPE cable insulation." Journal of Non-Crystalline Solids. 353 (2007): 4462-4466. AbstractWebsite

Cross-linked polyethylene (XLPE) is currently widely used as an insulating material for power cables due to its good physical properties, however when in use it undergoes an electrical ageing process. Its ability to trap electric charge can give rise to space charge accumulation in the bulk of the polymer and produce localised electric stresses that can lead to cable failure, since the electric field will be increased above the design stress in some regions favouring the initiation of degradation there. In this work the PEA (pulsed electro-acoustic) method was used to compare the charge dynamics in three samples (XLPE cable peelings) aged in different ways (electrothermally in the laboratory, field aged in service and thermally aged in the laboratory). Very different transient behavior was found depending upon the ageing history. This is related to differences in the migration of chemical species in the insulation layer, which are known to act as charge traps. All materials showed heterocharge peaks when the space charge reached stability, the magnitude of which seems to be related to the severity of the ageing. (c) 2007 Elsevier B.V. All rights reserved.