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2004
Pauleta, Sr., F. Guerlesquin, C. F. Goodhew, B. Devreese, J. VanBeeumen, AS Pereira, I. Moura, and G. W. Pettigrew. "Paracoccus pantotrophus pseudoazurin is an electron donor to cytochrome c peroxidase." Biochemistry. 43 (2004): 11214-11225. AbstractWebsite

The gene for pseudoazurin was isolated from Paracoccus pantotrophus LMD 52.44 and expressed in a heterologous system with a yield of 54.3 mg of pure protein per liter of culture. The gene and protein were shown to be identical to those from P. pantotrophus LMD 82.5. The extinction coefficient of the protein was re-evaluated and was found to be 3.00 mM(-1) cm(-1) at 590 nm. It was confirmed that the oxidized protein is in a weak monomer/dimer equilibrium that is ionic- strength-dependent. The pseudoazurin was shown to be a highly active electron donor to cytochrome c peroxidase, and activity showed an ionic strength dependence consistent with an electrostatic interaction. The pseudoazurin has a very large dipole moment, the vector of which is positioned at the putative electron-transfer site, His81, and is conserved in this position across a wide range of blue copper proteins. Binding of the peroxidase to pseudoazurin causes perturbation of a set of NMR resonances associated with residues on the His81 face, including a ring of lysine residues. These lysines are associated with acidic residues just back from the rim, the resonances of which are also affected by binding to the peroxidase. We propose that these acidic residues moderate the electrostatic influence of the lysines and so ensure that specific charge interactions do not form across the interface with the peroxidase.

Pereira, L., A. Marques, H. Águas, N. Nedev, S. Georgiev, E. Fortunato, and R. Martins. "Performances of hafnium oxide produced by radio frequency sputtering for gate dielectric application." Materials Science and Engineering: B. 109 (2004): 89-93. Abstract
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Inacio, P., J. N. Marat-Mendes, and C. J. Dias. "A piezoelectric pseudo-composite polymer film for the detection of proteins." Advanced Materials Forum Ii. Eds. R. Martins, E. Fortunato, I. Ferreira, and C. Dias. Vol. 455-456. Materials Science Forum, 455-456. 2004. 411-414. Abstract
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Pereira, L., H. Aguas, R. M. Martins, E. Fortunato, and R. Martins. "Polycrystalline silicon obtained by gold metal induced crystallization." Journal of non-crystalline solids. 338 (2004): 178-182. Abstract
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Pereira, L., H. Aguas, R. M. S. Martins, P. Vilarinho, E. Fortunato, and R. Martins. "Polycrystalline silicon obtained by metal induced crystallization using different metals." Thin Solid Films. 451 (2004): 334-339. Abstract
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Ferreira, I., R. Igreja, E. Fortunato, and R. Martins. "Porous a/nc-Si : H films produced by HW-CVD as ethanol vapour detector and primary fuel cell." Sensors and Actuators B-Chemical. 103 (2004): 344-349. Abstract
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Ferreira, Isabel, Rui Igreja, Elvira Fortunato, and Rodrigo Martins. "Porous a/nc-Si: H films produced by HW-CVD as ethanol vapour detector and primary fuel cell." Sensors and Actuators B: Chemical. 103.1 (2004): 344-349. Abstract
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Ferreira, Isabel, Hugo Águas, Luı́s Pereira, Elvira Fortunato, and Rodrigo Martins. "Properties of a-Si: H intrinsic films produced by HWPA-CVD technique." Thin solid films. 451 (2004): 366-369. Abstract
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Ferreira, Isabel, Hugo Águas, Elvira Fortunato, Rodrigo Martins, and others. "Properties of a-Si: H intrinsic films produced by HWPA-CVD technique." Thin solid films. 451 (2004): 366-369. Abstract
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Dias, C. J., R. Igreja, R. Marat-Mendes, P. Inacio, J. N. Marat-Mendes, and D. K. Das-Gupta. "Recent advances in ceramic-polymer composite electrets." Ieee Transactions on Dielectrics and Electrical Insulation. 11 (2004): 35-40. Abstract
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Dias, C. J., R. Igreja, R. Marat-Mendes, P. Inacio, J. N. Marat-Mendes, and D. K. Das-Gupta. "Recent advances in ceramic-polymer composite electrets." Ieee Transactions on Dielectrics and Electrical Insulation. 11 (2004): 35-40. AbstractWebsite
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Martins, M. C., A. M. Costa, J. P. Santos, F. Parente, and P. Indelicato. "Relativistic calculation of two-electron one-photon and hypersatellite transition energies for 12<=Z<=30 elements." Journal of Physics B: Atomic and Molecular Physics. 37 (2004): 3785-3795. AbstractWebsite

Energies of two-electron one-photon transitions from initial double K-hole states were computed using the Dirac–Fock model. The transition energies of competing processes, the Ka hypersatellites, were also computed. The results are compared with experiment and to other theoretical calculations.

Moniz, António Resultados provisórios do exercício Delphi WorTiS (1ª fase)[Provisional results of the 1st round of Delphi WorTiS exercise]. University Library of Munich, Germany, 2004. Abstract

In this working paper are present the main provisional results of the first round of a Delphi survey held in Portugal on the automotive sector. It was done under the WorTiS project, developed by IET – Research Centre on Enterprise and Work Innovation, and financed by the Portuguese Ministry of Science and Technology. The majority of experts consider to have an average of less knowledge in almost all the scenario topics presented. Nevertheless, we considered specially the topics where the experts considered themselves to have some knowledge. There were no “irrelevant” topics considered as such by the expert panel. There are also no topics that is not considered a need for co-operation (that happens in jus tone case). The lack of technological infra-structrures was not considered as an hindered factor for the accomplishement of any scenario. The experts panel considered no other international competence besides US, Japan or Germany in these topics. Although the members of the expert panel were not as many as needed, These situations will be taken into consideration for a second round of the Delphi survey

Pereira, Lu{\'ıs, Hugo Águas, Leandro Raniero, Rui Miguel S. Martins, Elvira Fortunato, and Rodrigo Martins. "Role of substrate on the growth process of polycrystalline silicon thin films by low-pressure chemical vapour deposition." Materials Science Forum. Vol. 455. Trans Tech Publications, 2004. 112-115. Abstract
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Aguas, H., L. Raniero, L. Pereira, A. S. Viana, E. Fortunato, and R. Martins. "Role of the rf frequency on the structure and composition of polymorphous silicon films." Journal of non-crystalline solids. 338 (2004): 183-187. Abstract
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Cunha, P. P., O. Mateus, and MT Antunes. "The sedimentology of the Paimogo dinosaur nest site (Portugal, Upper Jurassic)." 23 rd IAS Meeting of Sedimentology. Coimbra, Portugal 2004. 93. Abstract
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Cunha, P. P., O. Mateus, and MT Antunes. "The sedimentology of the Paimogo dinosaur nest site (Portugal, Upper Jurassic)." 23 rd IAS Meeting of Sedimentology. Coimbra, Portugal 2004. 93. Abstract
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Silva, A., Leandro Raniero, E. Ferreira, Hugo Águas, Lu{\'ıs Pereira, Elvira Fortunato, and Rodrigo Martins. "Silicon etching in CF4/O2 and SF6 atmospheres." Materials Science Forum. Vol. 455. Trans Tech Publications, 2004. 120-123. Abstract
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Lanca, M. C., E. R. Neagu, R. M. Neagu, C. J. Dias, J. N. Marat-Mendes, and D. K. Das-Gupta. "Space charge studies in LDPE using combined isothermal and non-isothermal current measurements." Ieee Transactions on Dielectrics and Electrical Insulation. 11 (2004): 25-34. AbstractWebsite

Using a recently developed procedure combining isothermal and non-isothermal current measurements space charge trapping and transport in LDPE was successfully studied. Unaged, thermally and electrically aged samples were investigated. The samples were conditioned before each measurement in order to obtain reproducible results. In the non-isothermal measurements appeared a broad peak (40degreesC to 50degreesC) that was possible to decompose into two or three peaks (35, 45 and 65degreesC). At even higher temperature another peak was sometimes present (85degreesC) depending on the prior sample conditioning. The space charge is trapped near the surface in deep traps (maximum depth of approximate to 15 mum). Relaxation times, mobilities and activation energies have been calculated for different charging/discharging conditions. For unaged samples the reproducibility of the results was poor while for the aged polyethylene it was quite good, meaning that aging helps conditioning. In the electrically aged LDPE there is a decrease of conductivity and the broad peak of the non-isothermal spectra shows a slight shift towards higher temperatures when compared with the data found in the thermally aged polymer.

Lanca, M. C., E. R. Neagu, R. M. Neagu, C. J. Dias, J. N. Marat-Mendes, and D. K. Das-Gupta. "Space charge studies in LDPE using combined isothermal and non-isothermal current measurements." Ieee Transactions on Dielectrics and Electrical Insulation. 11 (2004): 25-34. AbstractWebsite

Using a recently developed procedure combining isothermal and non-isothermal current measurements space charge trapping and transport in LDPE was successfully studied. Unaged, thermally and electrically aged samples were investigated. The samples were conditioned before each measurement in order to obtain reproducible results. In the non-isothermal measurements appeared a broad peak (40degreesC to 50degreesC) that was possible to decompose into two or three peaks (35, 45 and 65degreesC). At even higher temperature another peak was sometimes present (85degreesC) depending on the prior sample conditioning. The space charge is trapped near the surface in deep traps (maximum depth of approximate to 15 mum). Relaxation times, mobilities and activation energies have been calculated for different charging/discharging conditions. For unaged samples the reproducibility of the results was poor while for the aged polyethylene it was quite good, meaning that aging helps conditioning. In the electrically aged LDPE there is a decrease of conductivity and the broad peak of the non-isothermal spectra shows a slight shift towards higher temperatures when compared with the data found in the thermally aged polymer.

Lanca, M. C., E. R. Neagu, R. M. Neagu, C. J. Dias, J. N. Marat-Mendes, and D. K. Das-Gupta. "Space charge studies in LDPE using combined isothermal and non-isothermal current measurements." Ieee Transactions on Dielectrics and Electrical Insulation. 11 (2004): 25-34. AbstractWebsite
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Lanca, M. C., E. R. Neagu, R. M. Neagu, C. J. Dias, J. N. Marat-Mendes, and D. K. Das-Gupta. "Space charge studies in LDPE using combined isothermal and non-isothermal current measurements." Ieee Transactions on Dielectrics and Electrical Insulation. 11 (2004): 25-34. Abstract
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Figueiredo, MO, TP Silva, JP Veiga, J. Mirão, and S. Pascarelli. "Speciation of antimony in ancient tile glazes: a XAFS study." 14 th ESRF Users Meetg (2004): 8-13. Abstract
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Raniero, L., N. Martins, P. Canhola, S. Pereira, I. Ferreira, E. Fortunato, and R. Martins. "Spectral response of large area amorphous silicon solar cells." High Temperature Material Processes (An International Quarterly of High-Technology Plasma Processes). 8.2 (2004). Abstract
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Pereira, L., H. Aguas, R. Igreja, R. M. S. Martins, N. Nedev, L. Raniero, E. Fortunato, and R. Martins. "Sputtering preparation of silicon nitride thin films for gate dielectric applications." Advanced Materials Forum Ii. Eds. R. Martins, E. Fortunato, I. Ferreira, and C. Dias. Vol. 455-456. Materials Science Forum, 455-456. 2004. 69-72. Abstract
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