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Trace element emissions. Semi-annual report, October 1994--February 1995
Many trace elements can exist in raw coal gas either in the form of metallic vapors or gaseous compounds which, besides their action on potentially ``very clean`` advanced power generating systems such as fuel cells and gas turbines, can also be detrimental to plant and animal life when released into the atmosphere. Therefore, volatile trace contaminants from coal which can also be toxic must be removed before they become detrimental to both power plant performance/endurance and the environment. Five trace elements were selected in this project based on: abundance in solid coal, volatility during gasification, effects on downstream systems and toxicity to plant and animal life. An understanding was sought in this investigation of the interactions of these five trace elements (and their high temperature species) with the different components in integrated cleanup and power generating systems, as well as the ultimate effects with respect to atmospheric emissions. Utilizing thermodynamic calculations and various experimental techniques, it was determined that a number of trace contaminants that exist in coal may be substantially removed by flyash, and after that by different sorbent systems. High temperature cleanup of contaminants by sorbents such as zinc titanate, primarily to remove sulfur, can also absorb some metallic contaminants such as cadmium and antimony. Further polishing will be required, however, to eliminate trace contaminant species incorporating the elements arsenic, selemium, lead, and mercury
Du rythme dans le corps. Quelques notes sur l'interprétation du pouls par le médecin Hérophile
Pigeaud J.-M. Du rythme dans le corps. Quelques notes sur l'interprétation du pouls par le médecin Hérophile. In: Bulletin de l'Association Guillaume Budé, n°3, octobre 1978. pp. 258-267
Palaeolithic cave art in West France: an exceptional discovery: the Margot Cave (Mayenne)
International audienceFrom sites such as Lascaux, Chauvet and Cosquer in the south of France (Perigord, Ardèche and ouches-du-Rhône) and Altamira in Spain (Cantabria), cave art in the south of Europe is very well-known. But for a long time, cave art has been far less commonly encountered in the North. This situation is changing with a series of recent discoveries in England (Bahn et al. 2003), in France (Baffier & Girard 1996) and in Germany (Conard & Uermann 2000). It has strengthened the group of the seven decorated caves already discovered in Normandy, Central France and in Mayenne (Pigeaud 2004), to which we can include the fragments of rock painting from the cave of Geissenklösterle, in Germany (Hahn 1986). In this paper, we are presenting the discovery in July 2005 of Palaeolithic engravings and paintings in the Margot cave (Mayenne). This is the first decorated cave identified in Western France since 1967 and the thirteenth known in Northern Europe. The radiocarbon dating from some of these sites and the stylistic attributions of others authorize us to define a cultural group at the end of the Upper Palaeolithic. The period (around 12 000 BP) corresponds to a time when climatic conditions facilitated the progression of prehistoric humans to the North (Plumet 2004)
Palaeolithic cave art in West France: an exceptional discovery: the Margot Cave (Mayenne)
From sites such as Lascaux, Chauvet and Cosquer in the south of France (Perigord, Ardèche and ouches-du-Rhône) and Altamira in Spain (Cantabria), cave art in the south of Europe is very well-known. But for a long time, cave art has been far less commonly encountered in the North. This situation is changing with a series of recent discoveries in England (Bahn et al. 2003), in France (Baffier & Girard 1996) and in Germany (Conard & Uermann 2000). It has strengthened the group of the seven decorated caves already discovered in Normandy, Central France and in Mayenne (Pigeaud 2004), to which we can include the fragments of rock painting from the cave of Geissenklösterle, in Germany (Hahn 1986). In this paper, we are presenting the discovery in July 2005 of Palaeolithic engravings and paintings in the Margot cave (Mayenne). This is the first decorated cave identified in Western France since 1967 and the thirteenth known in Northern Europe. The radiocarbon dating from some of these sites and the stylistic attributions of others authorize us to define a cultural group at the end of the Upper Palaeolithic. The period (around 12 000 BP) corresponds to a time when climatic conditions facilitated the progression of prehistoric humans to the North (Plumet 2004). Domaine
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