VII Hutton Symposium on Granites and Related Rocks, Avila, Spain, July 4-9, 2011

Comunicação apresentada em: EMAS 2013 : 13th European Workshop on Modern Developments and Applications in Microbeam Analysis, Centro de Congressos da Alfândega do Porto, Portugal, 12 to 16 May 2013; A sample of cryolite was studied with a JEOL JXA 8500-F electron microprobe under several operating conditions. A TAP crystal was used to analyse Na and Al and a LDE1 crystal to analyse F. As F and Na are both highly "volatile" elements, special care must be taken during analysis. The measurement order of Na, F and Al is not irrelevant and optimum conditions may also result in different combinations of accelerating voltage, beam current, beam size or counting times. Relevant X-ray signals were recorded in order to investigate the behaviour of the Na Ka and F Ka counts with elapsed time. The incident beam current was also recorded at the same time. In a clear contrast to what has normally been reported in the EPMA analysis of aluminosilicates and silicate glasses, we found that the Na X-ray counts increase with time. This increment of X-rays intensities for sodium in cryolite depends on the operating conditions and is accompanied by a strong migration of fluorine from the beam excitation volume, leading to a decrease in F X-ray counting rates. It was also observed that higher incident beam currents induce higher radiation damage in the mineral. The current instability is consistent with possible electron induced dissociation in the cryolite structure. An analytical protocol was achieved for 6 kV and 15kV accelerating voltage for the correct EPMA analysis of cryolite.

Within a sustainable development framework, wind energy in Portugal during 2013 continued the trend of the previous years and increased its influence in the Portuguese electricity system. This influence was felt in several ways. Portugal added 192 MW of installed wind power capacity and reached 4,709 MW of wind generation. This represents 23% of renewable energy capacity in the country. With this amount of wind capacity, 11.9 TWh was supplied to the electricity system during the year (1), (2). These increases resulted in a wind power penetration rate of 24% in electricity consumption, rising 4% compared to 2012. The high value of wind penetration was influenced by the especially favorable wind conditions observed in mountain areas where the majority of the installed wind capacity is concentrated. It is important to notice that this amount of penetration is only exceeded worldwide by Denmark. The generation of electricity from renewable energy sources was 57% of the national consumption (which is a new record in Portugal). The individual renewable contribution in Portugal was different from last year. After an atypical year in hydro power production in 2012 (due to the fifth driest year of the last 80 years), the contribution of this renewable energy source grew 17% during 2013 reaching 27 % of electrical demand. Due to this increase...

O reconhecimento do impacto da actividade humana no aquecimento global do planeta conduziu, nos últimos anos, ao lançamento de várias iniciativas nacionais e europeias com vista à redução das emissões de gases promotores de efeito de estufa, bem como da dependência de combustíveis fósseis. A preocupação em tornar mais eficiente a utilização de energia em geral, e da energia eléctrica em particular, tem conduzido à procura de novas soluções para a geração de energia e à adopção de medidas com vista à sensibilização das sociedades para a utilização eficiente dos recursos, incluindo os energéticos. Neste contexto, surgiram nos anos mais recentes conceitos tais como, Cidades Inteligentes e Cidades Sustentáveis, os quais recorrem, de forma natural, a sistemas de energias renováveis para produção de electricidade. O desenvolvimento do conceito de Cidades Inteligentes não foi, contudo, acompanhado do necessário desenvolvimento e disponibilização de metodologias de caracterização e quantificação do potencial energético dos recursos renováveis nas cidades, por forma a promover uma gestão e planeamento adequados dos recursos existentes e o desejável desenvolvimento urbano sustentável. Este trabalho apresenta uma metodologia baseada em tecnologias de informação geográfica que permite a quantificação do potencial renovável existente em meio urbano para a produção de electricidade (eólico e solar fotovoltaico). A metodologia desenvolvida foi aplicada a dois casos de estudo tendo os resultados permitido identificar...

Apontamentos para a unidade curricular de Geoquímica Ambiental - Módulo de Hidrogeoquímica

Comunicação apresentada no 6th Congress of Cities of Volcanoes, 31 May-4 June 2010, Tenerife, Spain

Apontamentos para a unidade cirricular de Geoquímica Ambiental - Módulo de Hidrogeoquímica

Comunicação apresentada em Powerpoint, composta por 11 slides