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2002
Lanca, M. C.;Neagu, E. R.;Marat-Mendes, and J. N. "Studies of space charge in electrically aged low density polyethylene." 11th International Symposium on Electrets. 2002. 19-22. Abstract
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Fernandes, FMB, R. Martins, MT Nogueira, R. J. C. Silva, P. Nunes, D. Costa, and I. Ferreira. "Structural characterisation of NiTi thin film shape memory alloys." Sensors and Actuators a-Physical. 99.1-2 (2002): 55-58. Abstract
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Nunes, Isabel L., Rita A. Ribeiro, and V. Machado Análise ergonómica de postos de trabalho apoiada por um sistema pericial difuso. 10º Congresso da APDIO (Associação Portuguesa de Investigação Operacional). Universidade Minho - Guimarães, 2002. Abstract
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Duarte, C. M. M., M. Crew, T. Casimiro, A. Aguiar-Ricardo, and M. Nunes Da Ponte. "Phase equilibrium for capsaicin + water + ethanol + supercritical carbon dioxide." Journal of Supercritical Fluids. 22.2 (2002): 87-92. AbstractWebsite
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Duarte, C. M. M., C. Menduiña, A. Aguiar-Ricardo, and M. Nunes Da Ponte. "Second and third virial coefficients of three binary mixtures containing xenon, at 273 K: Comparison between Xe + C2H6, Xe + C2H4 and Xe + CO2." Physical Chemistry Chemical Physics. 4.19 (2002): 4709-4715. AbstractWebsite
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Almeida, PL, M. H. Godinho, M. T. Cidade, P. Nunes, A. Marques, R. Martins, E. Fortunato, and J. L. Figueirinhas. "Composite systems for flexible display applications from cellulose derivatives." 127.1 (2002): 111-114. Abstract
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Nunes, P., F. M. Braz Fernandes, R. J. C. Silva, E. Fortunato, and R. Martins. "Structural characterisation of zinc oxide thin films produced by spray pyrolysis." Key Engineering Materials. 230-232 (2002): 599-602. AbstractWebsite
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Nunes, Isabel L. Sistema pericial difuso para apoio à análise ergonómica de postos de trabalho. Sessão científica do Dep Eng Mecânica e Industrial da FCT/UNL, 2002. Abstract
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Barão, M., J. M. Lemos, and R. Neves-Silva. "Reduced complexity adaptive nonlinear control of a distributed collector solar field." Journal of Process Control. 12 (2002): 131-141.
Fortunato, E., P. Nunes, D. Costa, D. Brida, I. Ferreira, and R. Martins. "Characterization of aluminium doped zinc oxide thin films deposited on polymeric substrates." Vacuum. 64.3 (2002): 233-236. Abstract
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Lanca, M. C., E. R. Neagu, and J. N. Marat-Mendes. "Combined isothermal and non-isothermal current measurements applied to space charge studies in low-density polyethylene." Journal of Physics D-Applied Physics. 35 (2002): L29-L32. AbstractWebsite

A new experimental procedure combining usual isothermal DC charging and discharging with non-isothermal current measurements has been recently proposed. It is mainly suitable for very high insulating polymers and it was successfully applied to the study of space charge trapping and transport in low-density polyethylene. The analysis of the isothermal currents revealed the presence of different traps whose characteristic (de)trapping times can be deduced. The isothermal procedures allowed the selective charging of the sample. By choosing the charging field and the ratio of charge/discharge times, non-isothermal analysis permitted the differentiation of three or four peaks (at approximate to50degreesC, approximate to65degreesC, approximate to70degreesC and approximate to85degreesC) associated with charge detrapping from surface or near-surface (<20 mum) traps. These traps have activation energies between 0.21 and 1.54 eV. The mobility at 30degreesC is around 5 x 10(-16) m(2) V-1 s(-1). Samples had to be conditioned before each experiment in order to obtain reproducible results.

Lanca, M. C., E. R. Neagu, and J. N. Marat-Mendes. "Combined isothermal and non-isothermal current measurements applied to space charge studies in low-density polyethylene." Journal of Physics D-Applied Physics. 35 (2002): L29-L32. AbstractWebsite

A new experimental procedure combining usual isothermal DC charging and discharging with non-isothermal current measurements has been recently proposed. It is mainly suitable for very high insulating polymers and it was successfully applied to the study of space charge trapping and transport in low-density polyethylene. The analysis of the isothermal currents revealed the presence of different traps whose characteristic (de)trapping times can be deduced. The isothermal procedures allowed the selective charging of the sample. By choosing the charging field and the ratio of charge/discharge times, non-isothermal analysis permitted the differentiation of three or four peaks (at approximate to50degreesC, approximate to65degreesC, approximate to70degreesC and approximate to85degreesC) associated with charge detrapping from surface or near-surface (<20 mum) traps. These traps have activation energies between 0.21 and 1.54 eV. The mobility at 30degreesC is around 5 x 10(-16) m(2) V-1 s(-1). Samples had to be conditioned before each experiment in order to obtain reproducible results.

Almeida, PL, M. H. Godinho, M. T. Cidade, P. Nunes, A. Marques, R. Martins, E. Fortunato, and J. L. Figueirinhas. "Composite systems for flexible display applications from cellulose derivatives." Synthetic metals. 127.1 (2002): 111-114. Abstract
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Viciosa, M. T., AM Nunes, A. Fernandes, PL Almeida, M. H. Godinho, and MD Dionísio. "Dielectric studies of the nematic mixture E7 on a hydroxypropylcellulose substrate." Liquid crystals. 29.3 (2002): 429-441. Abstract
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Nunes, P.a, Fortunato Tonello Braz Fernandes Vilarinho Martins E. a P. a. "Effect of different dopant elements on the properties of ZnO thin films." Vacuum. 64 (2002): 281-285. AbstractWebsite

In this work we studied the influence of the dopant elements and concentration on the properties of ZnO thin film deposited by spray pyrolysis. The results show that the doping affects the thin films properties mainly the electrical ones, function of dopant concentration and nature. The most important changes were observed for films doped with 1at% of indium which exhibit a resistivity of 1.9 × 10-1 Ωcm associated with a transmitance of 90%. After the annealing treatment, the resistivity of the film decreases to 5.9 × 10-3 Ωcm without significative changes in the optical properties. The films were also used to produce amorphous silicon solar cells where the best results were obtained for ZnO:In. © 2002 Elsevier Science Ltd. All rights reserved.

Marques, António, Isabel Ferreira, Rodrigo Martins, Patrícia Nunes, Hugo Águas, Elvira Fortunato, Daniel Costa, and Maria Elisabete V. Costa. "Highly conductive/transparent ZnO: Al thin films deposited at room temperature by rf magnetron sputtering." Key Engineering Materials. 230 (2002): 571-574. Abstract
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Fortunato, Elvira, Patr{\'ıcia Nunes, António Marques, Daniel Costa, Hugo Águas, Isabel Ferreira, Maria Elisabete V. Costa, and Rodrigo Martins. "Highly conductive/transparent ZnO: Al thin films deposited at room temperature by rf magnetron sputtering." Key Engineering Materials. Vol. 230. Trans Tech Publications, 2002. 571-574. Abstract
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Fortunato, Elvira, Patricia Nunes, Antonio Marques, Daniel Costa, Hugo Águas, Isabel Ferreira, M. E. V. Costa, Maria H. Godinho, Pedro L. Almeida, and Joao P. Borges. "Influence of the strain on the electrical resistance of zinc oxide doped thin film deposited on polymer substrates." Advanced Engineering Materials. 4.8 (2002): 610-612. Abstract
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Fortunato, Elvira, Patricia Nunes, António Marques, Daniel Costa, Hugo Aguas, Isabel Ferreira, M. E. V. Costa, Maria H. Godinho, Pedro L. Almeida, Joao P. Borges, and others. "Influence of the strain on the electrical resistance of zinc oxide doped thin film deposited on polymer substrates." Advanced Engineering Materials. 4 (2002): 610-612. Abstract
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Fortunato, Elvira, Patricia Nunes, António Marques, Daniel Costa, Hugo Aguas, Isabel Ferreira, M. E. V. Costa, Maria H. Godinho, Pedro L. Almeida, and Joao P. Borges. "Influence of the strain on the electrical resistance of zinc oxide doped thin film deposited on polymer substrates." Advanced Engineering Materials. 4.8 (2002): 610-612. Abstract
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Ley, L., AH Mahan, Y. Xu, E. Iwaniczko, DL Williamson, BP Nelson, Q. Wang, H. Umemoto, Y. Nozaki, and M. Kitazoe. "PART A." (2002). Abstract
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Nunes, P., Costa Fortunato Martins D. E. R. "Performances presented by zinc oxide thin films deposited by r.f. magnetron sputtering." Vacuum. 64 (2002): 293-297. AbstractWebsite

In this work, we report the electro-optical properties exhibited by ZnO:A1 thin films deposited by r.f. magnetron sputtering. The effect of the deposition parameters on the properties of the films were studied with the aim to determine the most suitable deposition conditions to obtain ZnO:Al thin films with a low resistivity and high transmittance, characteristics required for applications on optoelectronic devices. After annealing, the ZnO:Al thin films present a low resistivity (6.25 × 10-3 Ωcm) and a high transmittance (90%) when produced with a deposition pressure of 1.6 × 10-2 mbar and r.f. power of 150W. © 2002 Elsevier Science Ltd. All rights reserved.

Nunes, P., Fortunato Martins Vilarinho E. R. P. "Properties presented by ZnO thin films deposited by magnetron sputtering and spray pyrolysis." Key Engineering Materials. 230-232 (2002): 424-427. AbstractWebsite

The most common techniques used to produce ZnO thin films are the spray pyrolysis and the magnetron sputtering techniques, low and high cost processes respectively. The aim of this work is to compare the properties of the films produced by these two techniques. The predominant difference observed was on the morphological properties. The films produced by spray pyrolysis have a rougher surface than the ones obtained by sputtering. Also the effect of the thermal annealing treatment is much more prononnced for the ZnO thin films produced by spray pyrolysis. After heat treatment films exhibit similar electrical properties and their application to optoelectronic devices is demonstrated.

Phillips, AJL, F. Fonseca, V. Povoa, R. Castilho, and G. Nolasco. "A reassessment of the anamorphic fungus Fusicoccum luteum and description of its teleomorph Botryosphaeria lutea sp nov." Sydowia. 54 (2002): 59-77. Abstract
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Fernandes, Francisco Braz M., Rui Martins, M. Teresa Nogueira, Rui JC Silva, Patrı́cia Nunes, Daniel Costa, Isabel Ferreira, and Rodrigo Martins. "Structural characterisation of NiTi thin film shape memory alloys." Sensors and Actuators A: Physical. 99.1 (2002): 55-58. Abstract
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