Browsing by Issue Date, starting with "2009-09"
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- Recovery of wastes by pyrolysis: effect of experimental conditionsPublication . Paradela, Filipe; Pinto, Filomena; Ramos, Ana M.; Gulyurtlu, Ibrahim; Cabrita, IsabelThis work aimed to study the recovery of three types of waste by the process of pyrolysis: biomass, plastics and used tyres. The effects of experimental conditions in products yield and composition were studied. The increase of reaction time increased alkane content both in gas phase from 53% to 70% v/v and in liquid fraction from 48% to 60% w/w. The rise of reaction temperature led to a decrease of liquid yield (from 82% to 73% w/w), which was followed by the increase of solids and gases. The increase of reaction temperature also allowed the increase of the alkane content in gas phase from 39% to 70% v/v. The increase of initial pressure did not lead to appreciable variations in product yields or composition. The parameter that most affected products yield and composition was plastics content on the wastes initial mixture. The enhancement of this parameter increased liquids yield from 33% to 92% w/w, at the expenses of solids and gases contents and also decreased aromatics contents from 52% to 28% w/w.
- CIMP Faro'09 : II Joint Meeting of Spores-Pollen and Acritarch Subcommissions. AbstractsPublication . Fernandes, Paulo; Pereira, Zélia; Oliveira, José Tomás; Clayton, G.; Wicander, R.
- Chemical elements variation in leaves with different development stages of Cistus plants from S. Domingos mine area, South PortugalPublication . Batista, Maria Joao; Gonzalez-Fernandez, Oscar; Abreu, Maria Manuela; Carvalho, L.Soils and leaves of Cistus ladanifer L. and Cistus salviifolius L. in different stages of development (young and mature) were sampled in different sites of the S. Domingos mine. The soils are thin and were developed on heterogeneous materials of metallurgical slags, gossanous materials and weathered host rocks. In general, mature leaves have higher concentrations of As, Cu, Fe, Mn, Pb and Zn than young leaves. Nevertheless, in Moitinhos site the young leaves have higher concentrations of As, Cu and Mn than mature leaves. Near the mining buildings C. ladanifer leaves have higher concentrations of As in mature leaves than C. salviifolius. The Pb concentrations in mature leaves are significantly higher and C. ladanifer contain two fold more than C. salviifolius leaves. Cistus plants show different behaviour on the trace elements uptake and translocation. This knowledge is useful in order to implement remediation programs in mine areas of the Mediterranean region using these pioneer plants.
- Characterization of a concealed fault zone using P and S-wave seismic reflection dataPublication . Carvalho, João P. F.; Ghose, R.; Pinto, Carlos C.; Borges, José Fernando
- Geochemistry of minerals, waters and weathering from the Fonte Santa mine area, NE of PortugalPublication . Gomes, Maria Elisa Preto; Antunes, I. Margarida H. Ribeiro; Neiva, A.M.R.; Pacheco, F. A. L.; Silva, Paulo BravoThe quartz veins containing scheelite from Fonte Santa mine area were exploited for W between 1942 and 1982. At the end of November 2006, a flood event damaged the dam land of Fonte Santa mine and metal content of water increased. Fonte Santa mine area cuts the quartzites close to the Fonte Santa muscovite granite. The granite contains quartz, microcline, albite, muscovite, chlorite, columbite-tantalite, volframite, W-ixiolite and ilmenite. The quartz veins contain muscovite, chlorite, tourmaline, scheelite, pyrrhotite, pyrite, sphalerite, chalcopyrite, galena, arsenopyrite, magnetite, jarosite, phosphates of Pb, Fe and AI. The waters related to the Fonte Santa mine are poorly mineralized, with electrical conductivity < 965 ~S / cm, of mixed type or HCO3- and SO42- types. These waters have Fe and Mn contents that forbid to use that for human consumption and agriculture. Sodium, Mg and K water contents are associated with the alteration of albite, chlorite and muscovite of country rock, while Ca is related to the W-bearing quartz veins.
- CIMP Faro'09 : II Joint Meeting of Spores-Pollen and Acritarch Subcommissions. Palynostratigraphic contributions to the understanding the Southwest Portugal and Algarve Basin Geology, Portugal : Post Meeting Field-Trip, 23-24 September 2009Publication . Oliveira, José Tomás; Fernandes, Paulo; Pereira, Zélia; Borges, Marisa
- Scientific collaboration within and accross research teamsPublication . Correia, Zita; Cera, Rosália; Egreja, CatarinaThis paper presents part of the results achieved to date in the process of developing a collaboratory in two R&D organizations. A collaboratory corresponds to a laboratory without walls, in which scientists are connected to each other, to scientific instruments and to information, independently of time and location. These two cases are part of a broader research project engaged in building a collaboratory in order to share knowledge and resources among the Portuguese State Laboratories. The building of the collaboratory is anchored on three main tasks: a) information audits carried out in each of the organizations, in order to map the main information flows, entities, repositories and systems; b) information behaviour research, in order to gain insight into the organizational information culture and the researchers' information use; c) implementation of the appropriate infrastructure and tools, in order to accommodate information archiving and intelligent search, collaborative software, remote control of scientific instruments, and multi-channel access to the services. The case study strategy was adopted because it is particularly amenable to the triangulation of methods (namely document analysis, survey and interviewing) thus providing rich ingredients to characterize a specific context. Discourse analysis was the technique used to analyse the interview transcripts. The research sites are two government R&D institutions operating in the Civil Engineering and in the Nuclear Technology fields, respectively. In the process of preparing the ground to develop the collaboratory, interviews were carried out with researchers of those two organizations in order to understand what collaboration means for them, and how collaboration actually happens within specific research project teams, and on their organizational daily routine. Attention was also paid to the socio-professional networks of these researchers, in order to understand the role played by these networks in their lives. This paper focuses on the interpretative repertoires emerging in the course of the interviewing process. We expect that our understanding of the researchers' collaboration framework and the meaning they assign to it may help us shape the collaboratory.
- Optimisation of preparation and measurement protocols for luminescence dating of small samples from a suite of porcelains and faiencesPublication . Burbidge, Christopher Ian; Rodrigues, Ana L.; Dias, M. Isabel; Prudêncio, M. Isabel; Cardoso, Guilherme; Figueiredo, M. Ondina; Silva, Teresa; Matos, Maria Antónia; Pais, Alexandre Manuel
- Assessing the wave energy resource using remote sensed dataPublication . Pontes, M.T.; Bruck, M.; Lehner, S.The use of accurate remote sensed wave data in the coastal area (water depth up to 80m) will enable a high quality characterization of the wave energy resource. Work has been carried out with this objective for a number of years namely assessing the quality of the radar altimeter and SAR sensors data. In this paper a summary of the quality of wave period estimates from the NASA/CNES Jason radar altimeter is presented, showing that the analytical models that have been proposed in recent years provide already accurate results. This paper also includes a verification of ESA ENVISAT SAR data (height, period and direction parameters in addition to the shape of frequency spectra) against NDBC buoy data, which has shown good accuracy for wave energy resource assessment. However, the long Exact-Repeat-Period of NASA (10 days) and of ESA satellites (35 days) poses serious limitation to the usefulness of their wave measurements except for long-term wave climate assessment. These shortcomings are expected to be overcome by the new high spatial-resolution TerraSAR-X satellite that is obtaining reliable data for nearshore areas, being able to provide data at 2 - 3 day interval.
- Nonconventional production technologies for NiTi shape memory alloysPublication . Neves, Filipe; Fernandes, F. M. Braz; Martins, Isabel M.; Correia, J.B.; Oliveira, M.; Gaffet, E.; Wang, T. Y.; Lattemann, M.; Suffner, J.; Hahn, H.The development of new production technologies for NiTi Shape Memory Alloys (SMAs) is always challenging. Recently, we introduced two powder metallurgical (PM) processing routes involving mechanical activation of elemental powder mixtures and densification through extrusion or forging. Those processes were named Mechanically Activated Reactive Extrusion Synthesis (MARES) and Mechanically Activated Reactive FOrging Synthesis (MARFOS). Heat treatments were performed in order to adjust the B2-NiTi matrix composition, yielding a microstructure consisting of a homogeneous dispersion of Ni4Ti3 precipitates embedded in nanocrystalline B2-NiTi matrix. In the present study, we demonstrate the viability of those PM processes for producing NiTi SMAs. With insitu X-ray diffraction and differential scanning calorimetry it is shown that B2-NiTi matrix undergo a B2« R«B19 two-step phase transformation
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