4 resultados para atmosfera de forno

em Repositório Científico da Universidade de Évora - Portugal


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Os métodos volumétricos de recolha de amostras de ar constituem os métodos dominantes atualmente para a monitorização de aeroalergenos, sendo a metodologia “Hírst” a dominante para a monitorização do pólen atmosférico. Recentemente têm surgido alguns avanços metodológicos nesta área combinando tecnologias bioquímicas e imunológicas pelo que se empreendeu este estudo a fim de comparar uma tecnologia “Ciclone”, desenvolvida no âmbito de um projeto europeu do programa LIFE (LIFE05 ENV/F/000068), com o referido método padrão quanto à eficiência de captação do pólen atmosférico e à deteção de aeroalergenos polínicos. Métodos: Foram efetuadas amostragens do conteúdo polínico atmosférico dos períodos de polinização dos anos 2006 e 2007 mediante um coletor tipo “Hirst” (Burkard® Seven Day Recording Volumetric Spore Trap®) e um coletor tipo “Ciclone” (AeoluS®, Coriolis ® da Bertin Technologies), colocados lado a lado. Foram instalados sobre uma plataforma meteorológica situada no centro da cidade de Évora, 17m acima do nível do solo. As amostras foram analisadas de acordo com os protocolos estabelecidos para cada método. De forma complementar foi realizada uma correlação dos dados obtidos com os registos de inquéritos sintomatológicos efetuados por voluntários das consultas externas de Imunoalergologia do hospital do Espírito Santo em Évora. Todos aqueles que apresentaram queixas respiratórias durante 0 período primaveril efetuaram testes cutâneos em “Prick” modificado aos aeroalergenos mais frequentes na região, a fim de se determinar o respetivo Perl de sensibilidades. Resultados: Esperou-se com este estudo testar a eficácia de uma nova metodologia para deteção e análise de bioaerossóis, comparativamente com a metodologia padrão e com a sua relação sintomatologia atópica respiratória. /ABSTRACT - Nowadays volumetric methods for bioaerosols sampling constitute the main methods to monitor the aeroallergens whereas “Hirst" methodology is the most dominant method to monitor airborne pollen. Recently some methodological advances have been introduced in this area matching biochemical and immunological technologies and so a study was accomplished in order to compare a "Cyclone” technology, developed under the scope of a European project - the LFE program -, with the mentioned standard method in terms of efficiency of airborne pollen sampling and detection of aeroallergens. Methods: Air samples from the outdoor environment were collected during the pollination period, along the year 2006 and 2007 with a "Hirst"-t3pe collector (Burkard® Seven Day Recording Volumetric Spore Trap®) and a "Cyclone"-type collector (Aeolus®, Coriolis® Bertin Technologies), placed side by side. They were installed on a meteorological platform situated at the center of Évora, 17m above ground level. Samples were analyzed according to the established protocols by each method. In a complementary way a data correlation was done between the symptomatologic inquiries fiom volunteers of the Immunoallergology external consultations at the Hospital Espírito Santo, in Évora. Everyone declaring breathing complaints during the spring season had done modified skin 'Trick" tests to the most usual aeroallergens of the region Results: It is waited from this study to test the efficiency of a new methodology for detection and analysis of bioaerossols, comparatively with the standard methodology and and its relation with the atopic simptomatologic breathing

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Este relatório técnico tem como objetivo descrever o modo como os registos das amostras de dados, i.e., medições das grandezas meteorológicas fornecidas pelo Instituto Português do Mar e da Atmosfera (IPMA), ilha da Madeira, foram tratadas. Foram utilizados registos de oito estações meteorológicas distribuídas pela ilha. No relatório técnico estão descritos os processos de filtragem das medições de radiação solar global e radiação solar difusa, de temperatura máxima e mínima do ar, a correção da radiação solar difusa, o preenchimento de lacunas nas medições e a dimensão da amostra de dados utilizada em cada estação. Este relatório também descreve os métodos utilizados para preencher as lacunas nas séries de dados originais, bem como os métodos utilizados na construção do ano médio e do ano meteorológico típico. O ano meteorológico típico será posteriormente usado na simulação da produção de energia solar através de sistemas fotovoltaicos instalados na ilha da Madeira.

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NEW DATA ON THE CHRONOLOGY OF THE VALE DO FORNO SEDIMENTARY SEQUENCE (LOWER TAGUS RIVER TERRACE STAIRCASE) AND ITS RELEVANCE AS FLUVIAL ARCHIVE OF THE MIDDLE PLEISTOCENE IN WESTERN IBERIA Pedro P. Cunha 1, António A. Martins 2, Jan-Pieter Buylaert 3,4, Andrew S. Murray 4, Luis Raposo 5, Paolo Mozzi 6, Martin Stokes 7 1 MARE - Marine and Environmental Sciences Centre, Department of Earth Sciences, University of Coimbra, Portugal: pcunha@dct.uc.pt 2 MARE - Marine and Environmental Sciences Centre, Dep. Geociências, University of Évora, Portugal; aam@uevora.pt 3 Centre for Nuclear Technologies, Technical University of Denmark, Risø Campus, Denmark; jabu@dtu.dk 4 Nordic Laboratory for Luminescence Dating, Aarhus University, Risø DTU, Denmark; anmu@dtu.dk 5 Museu Nacional de Arqueologia, Lisboa, Portugal; 3raposos@sapo.pt 6 Department of Geosciences, University of Padova, Italy; paolo.mozzi@unipd.it 7 School of Geography, Earth and Environmental Sciences, University of Plymouth, UK; m.stokes@plymouth.ac.uk The stratigraphic units that record the evolution of the Tagus River in Portugal (study area between Vila Velha de Ródão and Porto Alto villages; Fig. 1) have different sedimentary characteristics and lithic industries (Cunha et al., 2012): - a culminant sedimentary unit (the ancestral Tagus, before the drainage network entrenchment) – SLD13 (+142 to 262 m above river bed – a.r.b.; with probable age ca. 3,6 to 1,8 Ma), without artefacts; - T1 terrace (+84 to 180 m; ca. 1000? to 900 ka), without artefacts; - T2 terrace (+57 to 150 m; top deposits with a probable age ca. 600 ka), without artefacts; - T3 terrace (+43 to 113 m; ca. 460 to 360? ka), without artefacts; - T4 terrace (+26 to 55 m; ca. 335 a 155 ka), Lower Paleolithic (Acheulian) at basal and middle levels but early Middle Paleolithic at top levels; - T5 terrace (+5 to 34 m; 135 to 73 ka), Middle Paleolithic (Mousterian; Levallois technique); - T6 terrace (+3 to 14 m; 62 to 32 ka), late Middle Paleolithic (late Mousterian); - Carregueira Sands (aeolian sands) and colluvium (+3 a ca. 100 m; 32 to 12 ka), Upper Paleolithic to Epipaleolithic; - alluvial plain (+0 to 8 m; ca. 12 ka to present), Mesolithic and more recent industries. The differences in elevation (a.r.b.) of the several terrace staircases results from differential uplift due to active faults. Longitudinal correlation with the terrace levels indicates that a graded profile ca. 200 km long was achieved during terrace formation periods and a strong control by sea base level was determinant for terrace formation. The Neogene sedimentary units constituted the main source of sediments for the fluvial terraces (Fig. 2). Geomorphological mapping, coupled with lithostratigraphy, sedimentology and luminescence dating (quartz-OSL and K-feldspar post-IRIR290) were used in this study focused on the T4 terrace, which comprises a Lower Gravels (LG) unit and an Upper Sand (US) unit. The thick, coarse and dominantly massive gravels of the LG unit indicate deposition by a coarse bed-load braided river, with strong sediment supply, high gradient and fluvial competence, during conditions of rapidly rising sea level. Luminescence dating only provided minimum ages but it is probable that the LG unit corresponds to the earlier part of the MIS9 (ca. 335 to 325 ka), immediately postdating the incision promoted by the very low sea level (reaching ca. -140 m) during MIS10 (362 to 337 ka), a period of relatively cold climate conditions with weak vegetation cover on slopes and low sea level. Fig. 1. Main Portuguese reaches in which the Tagus River can be divided (Lower Tagus Basin): I – from the Spanish border to Arneiro (a general E–W trend, mainly consisting of polygonal segments); II – from Arneiro to Gavião (NE–SW); III – from Gavião to Arripiado (E–W); IV – from Arripiado to Vila Franca de Xira (NNE-SSW); V – from Vila Franca de Xira to the Atlantic shoreline. The faults considered to be the limit of the referred fluvial sectors are: F1 – Ponsul-Arneiro fault (WSW-ENE); F2 – Gavião fault (NW-SE); F3 – Ortiga fault (NW-SE); F4 – Vila Nova da Barquinha fault (W-E); F5 – Arripiado-Chamusca fault (NNE-SSW). 1 – estuary; 2 – terraces; 3 – faults; 4 – Tagus main channel. The main Iberian drainage basins are also represented (inset). The lower and middle parts of the US unit, comprising an alternation of clayish silts with paleosols and minor sands to the east (flood-plain deposits) and sand deposits to the west (channel belt), have a probable age of ca. 325 to 200 ka. This points to formation during MIS9 to MIS7, under conditions of high to medium sea levels and warm to mild conditions. The upper part of the US unit, dominated by sand facies and with OSL ages of ca. 200 to 154 ka, correlates with the early part of the MIS6. During this period, progradation resulted from climate deterioration and relative depletion of vegetation that promoted enhanced sediment production in the catchment, coupled with initiation of sea-level lowering that increased the longitudinal slope. The Vale do Forno and Vale da Atela archaeological sites (Alpiarça, central Portugal) document the earliest human occupation in the Lower Tagus River, well established in geomorphological and environmental terms, within the Middle Pleistocene. The Lower Palaeolithic sites were found on the T4 terrace (+26 m, a.r.b.). The oldest artefacts previously found in the LG unit, display crude bifacial forms that can be attributed to the Acheulian, with a probable age of ca. 335 to 325 ka. The T4 US unit has archaeological sites stratigraphically documenting successive phases of an evolved Acheulian, that probably date ca. 325 to 300 ka. Notably, these Lower Palaeolithic artisans were able to produce tools with different sophistication levels, simply by applying different strategies: more elaborated reduction sequences in case of bifaces and simple reduction sequences to obtain cleavers. Fig. 2. . Simplified geologic map of the Lower Tagus Cenozoic basin, adapted from the Carta Geológica de Portugal, 1/500000, 1992). The study area (comprising the Vale do Forno and Vale de Atela sites) is located on the more upstream sector of the Lower Tagus River reach IV, between Arripiado and Chamusca villages. 1 – alluvium (Holocene); 2 – terraces (Pleistocene); 3 – sands, silts and gravels (Paleogene to Pliocene); 4 – Sintra Massif (Cretaceous); 5 – limestones, marls, silts and sandstones (Mesozoic); 6 – quartzites (Ordovician); 7 – basement (Proterozoic to Palaeozoic); 8 – main fault. The main Portuguese reaches of the Tagus River are identified (I to V). The VF3 site (Milharós), containing a Final Acheulian industry, with fine and elaborated bifaces) found in a stratigraphic level located between the T4 terrace deposits and a colluvium associated with Late Pleistocene aeolian sands (32 to 12 ka), has an age younger than ca. 154 ka but much older than 32 ka. In the study area, the sedimentary units of the T4 terrace seem to record the river response to sea-level changes and climatically-driven fluctuations in sediment supply. REFERENCES Cunha P. P., Almeida N. A. C., Aubry T., Martins A. A., Murray A. S., Buylaert J.-P., Sohbati R., Raposo L., Rocha L., 2012, Records of human occupation from Pleistocene river terrace and aeolian sediments in the Arneiro depression (Lower Tejo River, central eastern Portugal). Geomorphology, vol. 165-166, pp. 78-90.

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The exchanges between lakes and the atmosphere at Alqueva reservoir, Southeast Portugal, are the object of a 2014 Summer experiment described in this work, with special attention to above water, air-water interface and below water measurements. Air-water interface momentum, heat and mass (H 2 O and CO 2 ) fluxes are obtained with the new Campbell Scientific’s IRGASON Integrated Open-Path CO 2 /H 2 O Gas Analyser and 3D Sonic Anemometer with a unique design that contains no special displacement between the sample volumes of the gas analyser and the sonic anemometer. The radiative balance, both in short and long wave, is assessed with an albedometer and a pirradiometer. Water temperature profile is also continuously recorded. In-water solar spectral downwelling irradiance profiles are measured which enable the computation of the attenuation coefficient of light in the water column. Thus, with detailed information of the Lake-Atmosphere interactions, it is possible to determine the energy and mass balance of the lake.