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2003
Lanca, M. C.;Dias,;Das C. J. Gupta, D. K.;Marat-Mendes, and J. "Comparative study of dielectric relaxation spectra of electrically and thermally aged low density polyethylene." 2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena. 2003. 161-164. Abstract
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Bonifacio, C., CA Cunha, A. Muller, C. G. Timoteo, JM Dias, I. Moura, and MJ Romao. "Crystallization and preliminary X-ray diffraction analysis of the di-haem cytochrome c peroxidase from Pseudomonas stutzeri." Acta crystallographica. 59 (2003): 345-7. AbstractWebsite

Crystals of cytochrome c peroxidase from Pseudomonas stutzeri were obtained using sodium citrate and PEG 8000 as precipitants. A complete data set was collected to a resolution of 1.6 A under cryogenic conditions using synchrotron radiation at the ESRF. The crystals belong to space group P2(1), with unit-cell parameters a = 69.29, b = 143.31, c = 76.83 A, beta = 100.78 degrees. Four CCP molecules were found in the asymmetric unit, corresponding to a pair of dimers related by local dyads. The crystal packing in the structure shows that the functional dimers can dimerize, as suggested by previous biochemical studies.

Silva, R. J. C., A. Hazotte, HMCM Santos, AMP Pinto, J. Lacaze, FMB Fernandes, and F. Hellal. "Carbon diffusion and compatibility stresses generated by temperature cycling of spheroidal graphite cast irons in the austenitic field." International Journal of Cast Metals Research. 16.1-3 (2003): 149-153. Abstract
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Salema, Maria Isabel Gomes, Ana Paula Barbosa-póvoa, and Augusto Q. Novais. "A capacitated multi-product reverse logistics network model with uncertainty." EUROMA/POMS Joint Conference Proceedings. Cernobbio, Italy 2003. 1-10. Abstract

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Karlovich, Alexei Yu., and Yuri I. Karlovich. "Compactness of commutators arising in the Fredholm theory of singular integral operators with shifts." Factorization, Singular Operators and Related Problems. Eds. Stefan Samko, Amarino Lebre, and António Ferreira dos Santos. Dordrecht: Kluwer Academic Publishers, 2003. 111-129. Abstract

The paper is devoted to the compactness of the commutators \(aS_\Gamma - S_\Gamma aI\) and \(W_\alpha S_\Gamma - S_\Gamma W_\alpha\), where \(S_\Gamma\) is the Cauchy singular integral operator, \(a\) is a bounded measurable function, \(W_\alpha\) is the shift operator given by \(W_\alpha f = f\circ\alpha\), and \(\alpha\) is a bi-Lipschitz homeomorphism (shift). The cases of the unit circle and the unit interval are considered. We prove that these commutators are compact on rearrangement-invariant spaces with nontrivial Boyd indices if and only if the function a or, respectively, the derivative of the shift a has vanishing mean oscillation.

Lourenço, João M., José C. Cunha, and Vitor Moreira. "Control and Debugging of Distributed Programs Using Fiddle." CoRR. cs.DC/0309049 (2003): 143-157. Abstractaadebug.pdfWebsite

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C. Oliveira, and J. Araújo. "A Criação em Teatro: proposta para um Thesaurus." Revista da Faculdade de Letras da Universidade de Lisboa. 27.5 (2003): 167-193. Abstract

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Goulão, Miguel. "CBSE: a Quantitative Approach." ECOOP Doctoral Symposium. Darmstadt, Germany 2003. Abstract
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Carvalho, AL, FMV Dias, JAM Prates, T. Nagy, HJ Gilbert, GJ Davies, LMA Ferreira, MJ Romao, and CMGA Fontes. "Cellulosome assembly revealed by the crystal structure of the cohesin-dockerin complex." Proceedings of the National Academy of Sciences of the United States of America. 100 (2003): 13809-13814. Abstract
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Cronauer, C., J. Engemann, A. Fejfar, I. Ferreira, P. Fojtik, E. Fortunato, L. Frohlich, S. Fukuda, G. Gasparro, and M. Geisler. "Chalvet, FN, 53 Choukourov, A., 86." Thin Solid Films. 442 (2003): 232. Abstract
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Fortunato, E., V. Assunção, A. Marques, I. Ferreira, H. Águas, L. Pereira, and R. Martins. "Characterization of transparent and conductive ZnO: Ga thin films produced by rf sputtering at room temperature." MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS. 763 (2003): 225-230. Abstract
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Fortunato, E., V. Assunç{\=a}o, A. Marques, I. Ferreira, H. Águas, L. Pereira, and R. Martins. "Characterization of transparent and conductive ZnO: Ga thin films produced by rf sputtering at room temperature." MRS Online Proceedings Library Archive. 763 (2003). Abstract
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Fortunate, E., Assunção Marques Ferreira Águas Pereira Martins V. A. I. "Characterization of transparent and conductive ZnO:Ga thin films produced by rf sputtering at room temperature." Materials Research Society Symposium - Proceedings. Vol. 763. 2003. 225-230. Abstract

Gallium-doped zinc oxide films were prepared by rf magnetron sputtering at room temperature as a function of the substrate-target distance. The best results were obtained for a distance of 10 cm, where a resistivity as low as 2.7×10-4 Ωcm, a Hall mobility of 18 cm2/Vs and a carrier concentration of 1.3×1021 cm-3 were achieved. The films are polycrystalline presenting a strong crystallographic c-axis orientation (002) perpendicular to the substrate. The films present an overall transmittance in the visible part of the spectra of about 85 %, in average. The low resistivity, accomplished with a high growth rate deposited at RT, enables the deposition of these films onto polymeric substrates for flexible applications.

Ferreira, I., E. Fortunato, and R. Martins. "Combining HW-CVD and PECVD techniques to produce a-Si: H films." Thin solid films. 427.1 (2003): 231-235. Abstract
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Ferreira, I., Fortunato Martins E. R. "Combining HW-CVD and PECVD techniques to produce a-Si:H films." Thin Solid Films. 427 (2003): 231-235. AbstractWebsite

Amorphous undoped a-Si:H films have been produced by hot wire plasma assisted chemical vapour deposition (HWPA-CVD), which combines the hot wire chemical vapour deposition (HW-CVD) and plasma enhanced chemical vapour deposition techniques. In this work we analyse the dissociation mechanism of the gas during the film growth in both processes with a quadrupole mass spectrometer. Besides that, the energy delivered to the gas dissociation is determined and correlated with the films properties. Thus, based on the results of the dissociated species for each deposition condition and process, we explain why the growth rate is enhanced when the filament temperature rises in HW-CVD process and why it decreases as r.f. power is enhanced in HWPA-CVD process. © 2002 Elsevier Science B.V. All rights reserved.

Lanca, M. C., C. J. Dias, D. K. Dasgupta, J. Marat-Mendes, and Ieee Ieee Comparative study of dielectric relaxation spectra of electrically and thermally aged low density polyethylene., 2003. AbstractWebsite

Low-density polyethylene (LDPE) films were thermally aged in a sodium chloride aqueous solution at constant temperature (thermal aging). Some of the samples were simultaneously immersed in solution and subjected to an electric AC field (electrical aging). The dielectric relaxation spectra at 30 degreesC in the range of 10(-5) Hz to 10(5) Hz were obtained for unaged and aged samples. For the low frequency (LF) region (10(-5) Hz to 10(-1) Hz) the time domain technique was used. A lock-in amplifier was used for the 10(-1) Hz to 10(1) Hz medium frequency (MF) region. While for the high frequency (HF), 10(-1) Hz to 10(5) Hz, RLC bridge measurements were performed. The main differences can be seen between electrically, thermally aged and unaged LDPE in the HF and LF regions. The LF peak is a broad peak related to localized space charge injection driven by the electric field. For electrically aged samples this peak increases in an earlier stage of electrical aging, decreasing afterwards. While in thermally aged samples the peak amplitude always increases with aging time. Finally the HF shows the beginning of a peak due to the gamma and beta transitions. This peak decreases with aging disappearing for the most aged samples.

Lanca, M. C., C. J. Dias, D. K. Dasgupta, J. Marat-Mendes, and Ieee Ieee Comparative study of dielectric relaxation spectra of electrically and thermally aged low density polyethylene., 2003. AbstractWebsite

Low-density polyethylene (LDPE) films were thermally aged in a sodium chloride aqueous solution at constant temperature (thermal aging). Some of the samples were simultaneously immersed in solution and subjected to an electric AC field (electrical aging). The dielectric relaxation spectra at 30 degreesC in the range of 10(-5) Hz to 10(5) Hz were obtained for unaged and aged samples. For the low frequency (LF) region (10(-5) Hz to 10(-1) Hz) the time domain technique was used. A lock-in amplifier was used for the 10(-1) Hz to 10(1) Hz medium frequency (MF) region. While for the high frequency (HF), 10(-1) Hz to 10(5) Hz, RLC bridge measurements were performed. The main differences can be seen between electrically, thermally aged and unaged LDPE in the HF and LF regions. The LF peak is a broad peak related to localized space charge injection driven by the electric field. For electrically aged samples this peak increases in an earlier stage of electrical aging, decreasing afterwards. While in thermally aged samples the peak amplitude always increases with aging time. Finally the HF shows the beginning of a peak due to the gamma and beta transitions. This peak decreases with aging disappearing for the most aged samples.

Lanca, M. C., C. J. Dias, D. K. Dasgupta, J. Marat-Mendes, and Ieee. "Comparative study of dielectric relaxation spectra of electrically and thermally aged low density polyethylene." 2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (2003): 161-164. Abstract
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Louren{\c c}o, João, Jos\´ e, and Vitor Moreira. "Control and Debugging of Distributed Programs Using Fiddle." CoRR. cs.DC/0309049 (2003).Website
Aguas, H., L. Pereira, A. Goullet, R. Silva, E. Fortunato, and R. Martins. "Correlation Between the Tunneling Oxide and IV Curves of MIS Photodiodes." MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS. Vol. 762. Warrendale, Pa.; Materials Research Society; 1999, 2003. 217-222. Abstract
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Aguas, H., L. Pereira, A. Goullet, R. Silva, E. Fortunato, R. Martins, JR Abelson, G. Ganguly, H. Matsumura, J. Robertson, and EA Schiff. "Correlation between the tunnelling oxide and I-V curves of MIS photodiodes." Amorphous and Nanocrystalline Silicon-Based Films-2003. Vol. 762. 2003. 217-222. Abstract
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Águas, H.a, Pereira Goullet Silva Fortunato Martins L. a A. b. "Correlation between the Tunnelling Oxide and I-V Curves of MIS Photodiodes." Materials Research Society Symposium - Proceedings. Vol. 762. 2003. 217-222. Abstract

In this work we present results of a study performed on MIS diodes with the following structure: substrate (glass) / Cr (2000Å) / a-Si:H n + (400Å) / a-Si:H i (5500Å) / oxide (0-40Å) / Au (100Å) to determine the influence of the oxide passivation layer grown by different techniques on the electrical performance of MIS devices. The results achieved show that the diodes with oxides grown using hydrogen peroxide present higher rectification factor (2×106) and signal to noise (S/N) ratio (1×107 at -1V) than the diodes with oxides obtained by the evaporation of SiO2, or by the chemical deposition of SiO 2 by plasma of HMDSO (hexamethyldisiloxane), but in the case of deposited oxides, the breakdown voltage is higher, 30V instead of 3-10 V for grown oxides. The ideal oxide thickness, determined by spectroscopic ellipsometry, is dependent on the method used to grow the oxide layer and is in the range between 6 and 20 Å. The reason for this variation is related to the degree of compactation of the oxide produced, which is not relevant for applications of the diodes in the range of ± 1V, but is relevant when high breakdown voltages are required.

Águas, H., L. Pereira, A. Goullet, R. Silva, E. Fortunato, and R. Martins. "Correlation Between the Tunnelling Oxide and IV Curves of MIS Photodiodes." MRS Proceedings. Vol. 762. Cambridge University Press, 2003. A18-16. Abstract
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Santos, J. P., F. Parente, and Y. K. Kim. "Cross sections for K-shell ionization of atoms by electron impact." Journal of Physics B: Atomic and Molecular Physics. 36 (2003): 4211-4224. AbstractWebsite

The relativistic version of the binary-encounter Bethe (BEB) model is used to calculate cross sections for K-shell ionization of atoms by electron impact. The BEB model requires only two atomic constants, the binding energy and kinetic energy of the K electrons. These constants are listed for carbon to antimony. Comparisons with available experimental data on N, O, Na, Al, Cl, Ca, Cu, Se and Sb show good agreement. The K-shell ionization cross sections for C, Mg, P, S, Cr, As and Cd are tabulated.

2002
Valtchev, Stanimir, Beatriz Borges, and Ben J. Klaassens. "Contactless Energy Transmission with Optimal Efficiency." IEEE 28th Annual Conference of the Industrial Electronics Society IECON 02. 2002. 1330-1335.