3,710 research outputs found

    Electrochemical study of aluminum corrosion in boiling high purity water

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    Electrochemical study of aluminum corrosion in boiling high-purity water includes an equation relating current and electrochemical potential derived on the basis of a physical model of the corrosion process. The work involved an examination of the cathodic polarization behavior of 1100 aluminum during aqueous oxidation

    Temporal patterns in the upstream migration of European eels (Anguilla anguilla) at the Couesnon estuarine dam

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    The temporal migration patterns of European glass eel Anguilla anguilla at the Couesnon estuarine dam (Mont-Saint-Michel Bay, France)were examined in winter and spring 2004 and 2005. The dam which is located close to the river mouth constitutes a major obstacle for upstreammigrating glass eels. The migration was observed at different temporal scales, from within individual tides to complete tidal cycles between successive spring tides. The maximum number of glass eels arrived downstream of the dam at the beginning and in the middle of the flood tide. Glass eels migrated through the dam openings preferentially from the middle of the flood to the beginning of the ebb tide. Eel densities were highest during the second tide of each tide cycle that arrived at the estuarine dam and when the difference in water level between upstream and downstream of the dam was greatest, particularly at the end of the flood. Analysis of the influence of each environmental factor provided a good prediction of the glass eel recruitment peaks and, therefore, of the most favourable temporal windows for their migration. The water level and temperature were the most important environmental factors. These results provide the information needed for a dam-management program that is compatible with glass eel migration

    European eel (Anguilla anguilla): prediction of spawner escapement from continental population parameters

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    This paper describes the assessment of silver European eel (Anguilla anguilla) escapement based on a “sedentary” population fraction analysis in a 60-km2 watershed of northern Brittany (France). Downstream migration fluxes were monitored using eel traps and related to environmental factors. Intensive electrofishing and fyke-net fishing were conducted to assess eel biomass, densities, and population structure. A total of 564 eels, including 81 silver eels, were PIT tagged. In 1996, 616 eels were caught in the catchment including 68 silver eels (11%). During the following downstream migration period, 12 of the PIT-tagged silver eels, among a total of 678, were recaptured in the downstream traps. Seven were recaptured in the catchment in 1997. It was shown that (i) only about 20% of the silver eels present in the catchment emigrated during the following year, (ii) 12% stayed in the catchment including two (3.4%) that recovered yellow eel characteristics, and (iii) the other eels either died or settled in the catchment but were not recaptured. It was also estimated that 2% (650 eels) of the population (34 000 eels) among 3000 silver eels considered “emigration candidates” emigrated each year

    Maintien de la paix et réforme des Nations Unies

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    Even though substantial administrative and financial changes have been introduced in the United Nations since the early 1980s, the end of the Cold War has brought about a turning point in its process of reform. The impressive growth of UN peacekeeping operations has tipped the balance in favor of major transformations in this field. Indeed, since the publication of the Secretary General’s (Agenda for Peace) many changes have been undertaken and improvements achieved. However much still needs to be done. This paper addresses three particular issues: institutional reforms, organizational reforms and reforms through adjustments. While little will be said on the first two issues, since they are relatively well known and treated elsewhere, this paper will focus on UN'S peacekeeping operations and their actual evolution as a way of assessing the continuing process of reform in the United Nations

    Le Forum de la Conférence mondiale des femmes, Nairobi, Kenya, 10-19 juillet 1985

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