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2012
Amaral, A., P. Brogueira, O. Conde, G. Lavareda, and C. Nunes de Carvalho. "Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities." THIN SOLID FILMS. 526 (2012): 221-224. Abstract

The influence of tin doping on the electrical, optical, structural and morphological properties of indium oxide films produced by radio-frequency plasma enhanced reactive thermal evaporation is studied, as transport properties are expected to improve with doping. Undoped and tin doped indium oxide thin films are deposited at room temperature using both pure In rods and (95-80) % In:(5-20) % Sn alloys as evaporation sources and 19.5 mW/cm(2) and 58.6 mW/cm(2) as rf-power densities. The two most important macroscopic properties - visible transparency and electrical resistivity - are relatively independent of tin content (0-20%). Visible transmittance of about 75% and electrical resistivity around 5 x 10(-4) Omega.cm can be observed in the films. The structural features are similar for all samples. Nevertheless, the surface morphology characterization shows that the homogeneity of the films varies according to the tin content. Moreover this variation is a balance between the rf-power and the tin content in the alloy: i) films with small and compact grains are produced at 58.6 mW/cm(2) from a 5% Sn alloy or at 19.5 mW/cm(2) from a 15% Sn alloy and consequently, smooth surfaces with reduced roughness and similar grain size and shape are obtained; ii) films showing the presence of aggregates randomly distributed above a tissue formed of thinner grains and higher roughness are produced at the other deposition conditions. (C) 2012 Elsevier B. V. All rights reserved.

Amaral, A., P. Brogueira, O. Conde, G. Lavareda, and C. Nunes de Carvalho. "Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities." THIN SOLID FILMS. 526 (2012): 221-224. Abstract

The influence of tin doping on the electrical, optical, structural and morphological properties of indium oxide films produced by radio-frequency plasma enhanced reactive thermal evaporation is studied, as transport properties are expected to improve with doping. Undoped and tin doped indium oxide thin films are deposited at room temperature using both pure In rods and (95-80) % In:(5-20) % Sn alloys as evaporation sources and 19.5 mW/cm(2) and 58.6 mW/cm(2) as rf-power densities. The two most important macroscopic properties - visible transparency and electrical resistivity - are relatively independent of tin content (0-20%). Visible transmittance of about 75% and electrical resistivity around 5 x 10(-4) Omega.cm can be observed in the films. The structural features are similar for all samples. Nevertheless, the surface morphology characterization shows that the homogeneity of the films varies according to the tin content. Moreover this variation is a balance between the rf-power and the tin content in the alloy: i) films with small and compact grains are produced at 58.6 mW/cm(2) from a 5% Sn alloy or at 19.5 mW/cm(2) from a 15% Sn alloy and consequently, smooth surfaces with reduced roughness and similar grain size and shape are obtained; ii) films showing the presence of aggregates randomly distributed above a tissue formed of thinner grains and higher roughness are produced at the other deposition conditions. (C) 2012 Elsevier B. V. All rights reserved.

Miller, A. Z., M. Hernandez-Marine, V. Jurado, A. Dionisio, P. Barquinha, E. Fortunato, M. J. Afonso, H. I. Chamine, and C. Saiz-Jimenez. "Enigmatic reticulated filaments in subsurface granite." Environmental Microbiology Reports. 4 (2012): 596-603. AbstractWebsite
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Lavareda, G., C. Nunes de Carvalho, A. M. Ferraria, A. M. Botelho Do Rego, and A. Amaral. "p-Type Cuo(X) Thin Films by rf-Plasma Enhanced Reactive Thermal Evaporation: Influence of rf-Power Density." JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY. 12 (2012): 6754-6757. Abstract

Copper oxide is a well known p-type semiconductor material, usually obtained by thermal oxidation of copper thin-films within few minutes, at atmospheric pressure. In this paper, thin films of copper oxide that were deposited by radio-frequency plasma enhanced reactive thermal evaporation of copper at room temperature, without any post-deposition annealing treatment, are studied. The deposition of good quality p-type semiconductor oxide to be used in the fabrication of p-TFTs is the purpose of this work. The thickness of the films varies from 97 up to 160 nm. The influence of rf power density on chemical, electrical and optical properties of the films was studied. Samples present conductivity within the range of 6 x 10(-5) to 4 x 10(2) Omega(-1) cm(-1) (thermal activation energy in the interval 0.46 to 0.01 eV). The p-type conductivity of the films was confirmed by Seebeck effect in the more conductive samples. Surface composition obtained by XPS analysis was correlated with optical and electrical properties, showing that rf-power plays a main role in changes of material characteristics.

Lavareda, G., C. Nunes de Carvalho, A. M. Ferraria, A. M. Botelho Do Rego, and A. Amaral. "p-Type Cuo(X) Thin Films by rf-Plasma Enhanced Reactive Thermal Evaporation: Influence of rf-Power Density." JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY. 12 (2012): 6754-6757. Abstract

Copper oxide is a well known p-type semiconductor material, usually obtained by thermal oxidation of copper thin-films within few minutes, at atmospheric pressure. In this paper, thin films of copper oxide that were deposited by radio-frequency plasma enhanced reactive thermal evaporation of copper at room temperature, without any post-deposition annealing treatment, are studied. The deposition of good quality p-type semiconductor oxide to be used in the fabrication of p-TFTs is the purpose of this work. The thickness of the films varies from 97 up to 160 nm. The influence of rf power density on chemical, electrical and optical properties of the films was studied. Samples present conductivity within the range of 6 x 10(-5) to 4 x 10(2) Omega(-1) cm(-1) (thermal activation energy in the interval 0.46 to 0.01 eV). The p-type conductivity of the films was confirmed by Seebeck effect in the more conductive samples. Surface composition obtained by XPS analysis was correlated with optical and electrical properties, showing that rf-power plays a main role in changes of material characteristics.

Safari, L., P. Amaro, S. Fritzsche, J. P. Santos, and F. Fratini. "Relativistic total cross section and angular distribution for Rayleigh scattering by atomic hydrogen." Physical Review A. 85 (2012): 043406. AbstractWebsite

We study the total cross section and angular distribution in Rayleigh scattering by hydrogen atom in the ground state, within the framework of Dirac relativistic equation and second-order perturbation theory. The relativistic states used for the calculations are obtained by making use of the finite basis-set method and expressed in terms of B splines and B polynomials. We pay particular attention to the effects that arise from higher (nondipole) terms in the expansion of the electron-photon interaction. It is shown that the angular distribution of scattered photons, while symmetric with respect to the scattering angle θ=90∘ within the electric dipole approximation, becomes asymmetric when higher multipoles are taken into account. The analytical expression of the angular distribution is parametrized in terms of Legendre polynomials. Detailed calculations are performed for photons in the energy range 0.5 to 10 keV. When possible, results are compared with previous calculations.

Pinho, Fernando F. S., Válter Lúcio, Luís Moura, Nuno Travassos, and Inês Almeida. "Avaliação das condições de durabilidade de ancoragens metálicas em paredes de alvenaria." CIRea2012 – Conferência Internacional sobre Reabilitação de Estruturas Antigas de Alvenaria. Págs. 81-92. ISBN 978-989-20-3080-7. Reitoria UNL, Lisboa 2012.
Wanderley, Fernando, Denis Silva da Silveira, João Araújo, and Maria Lencastre:. "Generating feature model from creative requirements using model driven design." First International Workshop on Requirements Engineering Practices on Software Product Line Engineering (REPOS 2012). Salvador, Brazil 2012.
Goulão, Miguel, Nelson Fonte, Michel Wermelinger, and Fernando Brito Abreu. "Software Evolution Prediction Using Seasonal Time Analysis: a Comparative Study." 16th European Conference on Software Maintenance and Reengineering (CSMR 2012). Szeged, Hungary: IEEE Computer Society, 2012. Abstractgoulao2012csmr.pdf

Prediction models of software change requests are useful for supporting rational and timely resource
allocation to the evolution process. In this paper we use a time series forecasting model to predict software
maintenance and evolution requests in an open source software project (Eclipse), as an example of projects with seasonal release cycles. We build an ARIMA model based on data collected from Eclipse’s change request tracking system since the project’s start. A change request may refer to defects found in the software, but also to suggested improvements in the system under scrutiny. Our model includes the identification of seasonal patterns and tendencies, and is validated through the forecast of the change requests evolution for the next 12 months. The usage of seasonal information significantly improves the estimation ability of this model, when compared to other ARIMA models found in the literature, and does so for a much longer estimation period. Being able to accurately forecast the change requests’ evolution over a fairly long time period is an important ability for enabling adequate process control in maintenance activities, and facilitates
effort estimation and timely resources allocation. The approach presented in this paper is suitable for projects with a relatively long history, as the model building process relies on historic data.

Barišić, Ankica, Vasco Amaral, and Miguel Goulão. "Usability Evaluation of Domain-Specific Languages." Simpósio de Estudantes de Doutoramento em Engenharia de Software (SEDES 2012), hosted by QUATIC 2012. Lisbon, Portugal: IEEE CPS, 2012. Abstractbarisic2012sedes.pdf

Domain-Specific Languages (DSLs) are claimed to bring important productivity improvements to developers,
when compared to General-Purpose Languages (GPLs). The increased Usability is regarded as one of the key benefits of DSLs when compared to GPLs, and has an important impact on the achieved productivity of the DSL users. So, it is essential to build in good usability while developing the DSL. The purpose of this proposal is to contribute to the systematic activity of Software Language Engineering by focusing on the
issue of the Usability evaluation of DSLs. Usability evaluation is often skipped, relaxed, or at least omitted from papers reporting development of DSLs. We argue that a systematic approach based on User Interface experimental validation techniques should be used to assess the impact of new DSLs. For that purpose, we propose to merge common Usability evaluation processes with the DSL development process. In order to provide reliable metrics and tools we should reuse and identify good practices that exist in Human-Computer
Interaction community.

Amado, M. P. "Arquitetura Sustentável e a Valia da Certificação da Construção." , 2ª Conferência de Reabilitação Sustentável de Edifícios no Espaço Lusófono. Caparica: FCT UNL - MAMAOT CV, 2012.
Ganhão, A. M., and M. P. Amado. "Eficiência Energética em Edifícios." 2ª Conferência de Reabilitação Sustentável de Edifícios no Espaço Lusófono. Caparica: FCT UNL - MAMAOT CV, 2012.
Lopes, T. C., and M. P. Amado. "Prefabricação Aplicada ao Contexto da Reabilitação de Edifícios." 2ª Conferência de Reabilitação Sustentável de Edifícios no Espaço Lusófono. Caparica: FCT UNL - MAMAOT CV, 2012.
Poggi, F., and M. P. Amado. "Sustentabilidade em Edifícios de Habitação: Um novo Sistema de Certificação." 2ª Conferência de Reabilitação Sustentável de Edifícios no Espaço Lusófono. Caparica: FCT UNL - MAMAOT CV, 2012.
Lucas, Vanessa, and Miguel P. Amado Vantages of Certification of Sustainable Construction. BSA 2012 – 1st International Conference on Building Sustainability Assessment. Porto, PT: Green Lines Institute, 2012.
Barroso, T., A. C. A. Roque, and A. Aguiar-Ricardo. "Bioinspired and sustainable chitosan-based monoliths for antibody capture and release." RSC Advances. 2.30 (2012): 11285-11294. AbstractWebsite
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Bonifácio, V. D. B., VG Correia, M. G. Pinho, J. C. Lima, and A. Aguiar-Ricardo. "Blue emission of carbamic acid oligooxazoline biotags." Materials Letters. 81 (2012): 205-208. AbstractWebsite
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Temtem, M., T. Barroso, T. Casimiro, J. F. Mano, and A. Aguiar-Ricardo. "Dual stimuli responsive poly(N-isopropylacrylamide) coated chitosan scaffolds for controlled release prepared from a non residue technology." Journal of Supercritical Fluids. 66 (2012): 398-404. AbstractWebsite
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Rosa, V., S. Realista, A. Mourato, L. M. Abrantes, J. Henriques, M. J. Calhorda, T. Avilés, M. G. B. Drew, and V. Félix. "1,1′-Bis(diphenylphosphino)ferrocene bridging two mono(cyclopentadienyl) cobalt moieties: Synthesis, structure, electrochemistry and DFT studies." Journal of Organometallic Chemistry. 712 (2012): 52-56. AbstractWebsite
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Chastre, Carlos, Válter Lúcio, Arnold Van Acker, Barry Crisp, Daniela Gutstein, Filipe Saraiva, Íria Doniak, Jason Krohn, José Barros Viegas, Marcelo Ferreira, Marco Menegotto, Mounir el Debs, Simon Hughes, Spyros Tsoukantas, and Stefano Pampanin Estruturas Pré-Moldadas no Mundo. Aplicações e Comportamento Estrutural. Brasil: Fundação da Faculdade de Ciência e Tecnologias da Universidade NOVA de Lisboa, 2012. AbstractWebsite

A indústria do betão pré fabricado é, por tradição, inovadora, precursora de novas tecnologias e de novos materiais.O processo produtivo de estruturas com elementos pré-fabricados difere significativamente do das estruturas betonadas em obra pelo facto de uma parte, ou a totalidade, dos elementos da estrutura serem produzidos em fábrica, em condições de produção melhoradas em relação às condições da obra, e serem posteriormente transportados para a obra, onde são, finalmente ligados entre si. A produção em fábrica é efectuada em ambiente protegido do Sol e da chuva, com operários fixos e com formação profissional para desenvolverem tarefas com procedimentos normalizados. Consequentemente, os elementos executados em fábrica possuem melhor qualidade, sob vários aspectos, do que as estruturas executadas em obra.Este livro divide-se em duas grandes áreas, numa primeira abordam-se algumas aplicações de estruturas pré-moldadas no mundo e numa segunda parte descreve-se o seu comportamento estrutural face a diferentes acções. Nos primeiros capítulos relata-se a experiência da pré-fabricação em três países de diferentes continentes: o Brasil, Portugal e a Austrália e revelam-se novas oportunidades que poderão surgir para a indústria da pré-fabricação. Nos capítulos seguintes dá-se um especial enfoque à investigação do comportamento das ligações (rígidas e semi-rígidas). Aborda-se o projecto de estruturas de betão pré-fabricado às acções acidentais. E por fim, dedicam-se os últimos capítulos ao comportamento das estruturas pré-fabricadas face às acções sísmicas. Nesta área, o bom desempenho das estruturas e grande parte do conhecimento e da tecnologia actual advém da resposta dada pelos engenheiros, investigadores e construtores aos fenómenos naturais que afectam as nossas construções, como comprova o desempenho das ligações dúcteis resistentes a momentos em edifícios pré fabricados de betão no verdadeiro teste sísmico que foram os sismos de Christchurch de 2010 e 2011.

Romain, C., V. Rosa, C. Fliedel, F. Bier, F. Hild, R. Welter, S. Dagorne, and T. Avilés. "Highly active zinc alkyl cations for the controlled and immortal ring-opening polymerization of ε-caprolactone." Dalton Transactions. 41.12 (2012): 3377-3379. AbstractWebsite
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Pedras, B., V. Rosa, R. Welter, C. Lodeiro, and T. Avilés. "New quinoline α-diimine ligands as fluorescent probes for metal ions: Ultrasound-assisted and conventional synthetic methods." Inorganica Chimica Acta. 381.1 (2012): 143-149. AbstractWebsite
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Li, L., P. S. Lopes, V. Rosa, C. A. Figueira, M. A. N. D. A. Lemos, M. T. Duarte, T. Avilés, and P. T. Gomes. "Synthesis and structural characterisation of (aryl-BIAN)copper(i) complexes and their application as catalysts for the cycloaddition of azides and alkynes." Dalton Transactions. 41.17 (2012): 5144-5154. AbstractWebsite
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Costa, Eunice, Margaret M. Lloyd, Caroline Chopko, Ana Aguiar-Ricardo, and Paula T. Hammond. "Tuning Smart Microgel Swelling and Responsive Behavior through Strong and Weak Polyelectrolyte Pair Assembly." LangmuirLangmuir. 28.26 (2012): 10082-10090. AbstractWebsite

The layer-by-layer (LbL) assembly of polyelectrolyte pairs on temperature and pH-sensitive cross-linked poly(N-isopropylacrylamide)-co-(methacrylic acid), poly(NIPAAm-co-MAA), microgels enabled a fine-tuning of the gel swelling and responsive behavior according to the mobility of the assembled polyelectrolyte (PE) pair and the composition of the outermost layer. Microbeads with well-defined morphology were initially prepared by synthesis in supercritical carbon dioxide. Upon LbL assembly of polyelectrolytes, interactions between the multilayers and the soft porous microgel led to differences in swelling and thermoresponsive behavior. For the weak PE pairs, namely poly(l-lysine)/poly(l-glutamic acid) and poly(allylamine hydrochloride)/poly(acrylic acid), polycation-terminated microgels were less swollen and more thermoresponsive than native microgel, whereas polyanion-terminated microgels were more swollen and not significantly responsive to temperature, in a quasi-reversible process with consecutive PE assembly. For the strong PE pair, poly(diallyldimethylammonium chloride)/poly(sodium styrene sulfonate), the differences among polycation and polyanion-terminated microgels are not sustained after the first PE bilayer due to extensive ionic cross-linking between the polyelectrolytes. The tendencies across the explored systems became less noteworthy in solutions with larger ionic strength due to overall charge shielding of the polyelectrolytes and microgel. ATR FT-IR studies correlated the swelling and responsive behavior after LbL assembly on the microgels with the extent of H-bonding and alternating charge distribution within the gel. Thus, the proposed LbL strategy may be a simple and flexible way to engineer smart microgels in terms of size, surface chemistry, overall charge and permeability.The layer-by-layer (LbL) assembly of polyelectrolyte pairs on temperature and pH-sensitive cross-linked poly(N-isopropylacrylamide)-co-(methacrylic acid), poly(NIPAAm-co-MAA), microgels enabled a fine-tuning of the gel swelling and responsive behavior according to the mobility of the assembled polyelectrolyte (PE) pair and the composition of the outermost layer. Microbeads with well-defined morphology were initially prepared by synthesis in supercritical carbon dioxide. Upon LbL assembly of polyelectrolytes, interactions between the multilayers and the soft porous microgel led to differences in swelling and thermoresponsive behavior. For the weak PE pairs, namely poly(l-lysine)/poly(l-glutamic acid) and poly(allylamine hydrochloride)/poly(acrylic acid), polycation-terminated microgels were less swollen and more thermoresponsive than native microgel, whereas polyanion-terminated microgels were more swollen and not significantly responsive to temperature, in a quasi-reversible process with consecutive PE assembly. For the strong PE pair, poly(diallyldimethylammonium chloride)/poly(sodium styrene sulfonate), the differences among polycation and polyanion-terminated microgels are not sustained after the first PE bilayer due to extensive ionic cross-linking between the polyelectrolytes. The tendencies across the explored systems became less noteworthy in solutions with larger ionic strength due to overall charge shielding of the polyelectrolytes and microgel. ATR FT-IR studies correlated the swelling and responsive behavior after LbL assembly on the microgels with the extent of H-bonding and alternating charge distribution within the gel. Thus, the proposed LbL strategy may be a simple and flexible way to engineer smart microgels in terms of size, surface chemistry, overall charge and permeability.