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Forest Fires In Portugal: How They Happen And Why They Happen, João F. Gomes Jan 2006

Forest Fires In Portugal: How They Happen And Why They Happen, João F. Gomes

João F Gomes

Forest fires are recurrent phenomena in Southern European countries, due to the nature of Mediterranean forest and climatic characteristics. However, in Portugal, in the last years, forest fires attained the dimension of public calamity and are now endangering sustainability of forest itself, as well as several derived economic activities. This paper reviews the past and current situation of forest fires in Portugal, analyses its main causes and consequences and derives recommendations to effectively overcome this problem.


Leaching Of Heavy Metals From Steelmaking Slags, João F. Gomes Jan 2006

Leaching Of Heavy Metals From Steelmaking Slags, João F. Gomes

João F Gomes

Leaching tests with EAF and Ladle slags were performed, using a flow through test and the standard batch test DIN 38414-S4. The previous method was used to simulate the leaching behaviour of steel slags under landfill. The chemical analysis of the leachates during this period shows, in general, for both types of slag, an increase of heavy metal releases with ageing. Standard test method DIN 38414-S4 was used to evaluate leachability of heavy metals by water in unprocessed slags. After more than one year of trials, slag samples submitted to these trials presented very low total leaching levels. The most …


Estimation Of Uncertainty In The Determination Of Nitrogen Oxides Emissions, João F. Gomes Jan 2006

Estimation Of Uncertainty In The Determination Of Nitrogen Oxides Emissions, João F. Gomes

João F Gomes

This paper presents a methodology for estimation of uncertainty on a reference test method for determination of nitrogen oxides concentration in gaseous emissions from stationary sources. As a first stage for identification of uncertainty sources, the test method is carefully reviewed in detail. Afterwards, these sources are quantified, bearing in mind its partial uncertainty, allowing the determination of the combined uncertainty and, finally, the expanded uncertainty. The calculation procedure was implemented into an excel calculation file. Using this file and considering several numerical applications from real situations, uncertainities around 15 mg/Nm3 over determined concentrations of 350 mg/Nm3 of NOx (expressed …


Fume Emissions During Metal Arc Welding, João F. Gomes Jan 2006

Fume Emissions During Metal Arc Welding, João F. Gomes

João F Gomes

No abstract provided.