Criterios para la aplicación de coeficientes modificativos de la curva S-N de fatiga

[ES]Este Trabajo de Fin de Grado tiene como objeto crear un programa que sirva como herramienta para los cálculos en las propiedades a fatiga de una pieza. El conjunto del trabajo se centra en su creación mediante la herramienta Excel. El programa cuenta con tres diferentes pestañas: una para los datos que debe introducir el usuario, otra correspondiente a los cálculos y por último una en la que aparecen los resultados. El usuario debe conocer las propiedades de la probeta del material a ensayar, así como el rango de ciclos en el cual se va a trabajar (siempre en un rango de ciclos medio alto). A partir de estas informaciones de la probeta, y gracias a la curva de Basquin y la ecuación de Marin, el programa será capaz de obtener la curva de resistencia a fatiga correspondiente para la pieza. Se incluyen también casos especiales en los que se realicen tratamientos mecánicos de mejora, con una tensión límite del proceso. Para obtener la curva S-N de la pieza se pedirá información en la pestaña de interfaz con el usuario sobre distintas propiedades de la pieza, que permitan así calcular los valores de los coeficientes de Marín gracias a la base de datos que contiene el programa. El usuario tiene también la opción de introducir él mismo los valores de los coeficientes para así obtener una curva que se aproxime más a sus resultados experimentales. En resumen, la función del programa es la de ser una calculadora de la resistencia fatiga de la pieza a partir de los datos que se disponen de la probeta.

L'économie argelienne et ses connexions avec l' Union Européenne de l'indépendance à l'actualité

Analyse about all the economical connexions between the European Union and Algeria since 1962 until 2014.

Ratio of natural isotopes of nitrogen. I. Primary results: soils of Dombes [Translation from: Revue d'Ecologie et de Biologie du Sol 14, 279-287, 1977]

Utilization of the heavy isotope of nitrogen as a tracer has found numerous applications in soil biology. It allows better definition of different stages of the nitrogen cycle, in particular the immobilization-mineralization cycle. In this work, the authors report the results of calculations of natural isotope ratios of nitrogen in samples of water, soil and vegetation prevailing in Dombes and discuss the possibilities of errors and coefficients of fractionation.

The role of ciliates in the pelagic life cycle of the Mediterranean [Translation from: Rapports et Proces Verbaux des Reunions-Conseil International pour l'Exploration de la Mer 17, 511-512, 1963]

During hydrographic and plankton studies carried out since 1960 in the coastal zone between the Ebro and Castellon (western Mediterranean), data has been collected which confirms the importance of ciliates in the composition and activity of the plankton. The ciliates in 413 samples of 100 ml of water were counted, having been examined with the Utermohl microscope after sedimentation. The samples studied were distributed according to the density of their population. subject for study. The author concludes that recognition of the role of ciliates as an important link in the food chain of the sea would simplify the interpretation of certain problems posed by the nutrition of certain groups of planktonic animals.

Vision 2050: changement climatique, pêche et aquaculture en Afrique de l’Ouest Du 14 au 16 avril 2010, Dakar, Sénégal

Ce rapport présente les activités et les résultats de l’atelier Vision 2050: Changement climatique, pêche et aquaculture en Afrique de l’Ouest. Les objectifs de l’atelier étaient de discuter les questions critiques et les incertitudes auxquelles est confronté le secteur de la pêche et de l’aquaculture au Ghana, au Sénégal et en Mauritanie, d’élaborer des scénarios sectoriels pour 2050 et de discuter de l’implication de ces scénarios dans le contexte du changement climatique pour ces pays et la région ouest africaine.

Magnetic Cross-Linked Enzyme Aggregates (mCLEAs) of Candida antarctica Lipase: An Efficient and Stable Biocatalyst for Biodiesel Synthesis

Enzyme-catalyzed production of biodiesel is the object of extensive research due to the global shortage of fossil fuels and increased environmental concerns. Herein we report the preparation and main characteristics of a novel biocatalyst consisting of Cross-Linked Enzyme Aggregates (CLEAs) of Candida antarctica lipase B (CALB) which are covalently bound to magnetic nanoparticles, and tackle its use for the synthesis of biodiesel from non-edible vegetable and waste frying oils. For this purpose, insolubilized CALB was covalently cross-linked to magnetic nanoparticles of magnetite which the surface was functionalized with –NH2 groups. The resulting biocatalyst combines the relevant catalytic properties of CLEAs (as great stability and feasibility for their reutilization) and the magnetic character, and thus the final product (mCLEAs) are superparamagnetic particles of a robust catalyst which is more stable than the free enzyme, easily recoverable from the reaction medium and reusable for new catalytic cycles. We have studied the main properties of this biocatalyst and we have assessed its utility to catalyze transesterification reactions to obtain biodiesel from non-edible vegetable oils including unrefined soybean, jatropha and cameline, as well as waste frying oil. Using 1% mCLEAs (w/w of oil) conversions near 80% were routinely obtained at 30°C after 24 h of reaction, this value rising to 92% after 72 h. Moreover, the magnetic biocatalyst can be easily recovered from the reaction mixture and reused for at least ten consecutive cycles of 24 h without apparent loss of activity. The obtained results suggest that mCLEAs prepared from CALB can become a powerful biocatalyst for application at industrial scale with better performance than those currently available.

Donati Artis Grammaticae Index et Concordantia

615 p.

Chaines de traitement des statistiques de pêche artisanale. II - annexes et codages

The different coding methods concerning artisanal collective fishing in the Ebrié lagoon, are exposed. For each computer program one example is proposed.

Eléments nutritifs et production primaire dans les lagunes du Côte d'Ivoire : cycle annuel

This paper collects most of the information gathered between October 1974 and July 1976 within the framework of a research program concerning the hydrobioclimate of ivorian lagoons and especially the Ebrié lagoon. Monthly surveys concerning the latter were carried out during 1975. The following parameters - and their vertical distribution wherever it had a meaning - were systematically gathered in a system of fifty-five stations: Transparency (Secchi), Temperature, Salinity, Chlorophylla, Dissolved oxygen, phosphate, nitrate, nitrite. These data provide an outline of the annual cycle of nutrients and primary production of the Ivoirian lagoons

Campagnes Nizery: Togo 3 (16 au 18/08/83) et Togo 4 (28 au 30/11/83). Resultats des chalutages

This publication gives the results of the bottom trawlings made during the cruises Togo 3 and logo 4 by the oceanographic research vessel "Andre NIZERY" on the continental shelf of Togo during the estimation program of halieutic resources. The report includes: 1 - The report of the cruises Togo 3 and Togo 4 2 - Some information on the presentation of the results 3 - The trawl recording cards for the 2 cruises 4 - The length frequency distributions of the measured samples.

Variation saisonniere des structures hydrologique et dynamique du plateau continental ivoirien (VASPI I, II, III)

This data report contains all the meteorological, hydrological and dynamic data gathered during the VASPI cruises (I : from December 8th to December 13th 1982, II : from March 5th to March 9th 1983, and III : from October 6th to October 10th 1983) carried out along the continental shelf of Ivory Coast by the oceanographic ship "Andre NIZERY". These cruises, which represent a part of a coastal programme, are included in the more general scientific program FOCAL, whose main scientific objective is the study of the thermal context of the intertropical atlantic area.

Résumé des connaissances actuelles sur la biologie et la pêche des thons tropicaux en Atlantique

This work summarizes the present knowledge on biology and fisheries of Atlantic tuna such as yellowfin (Thunnus albacares), skipjack (Katsuwonus pelamis) and to a lesser extent, bigeye (Thunnus obesus) and albacore (Thunnus alalunga). Current appraisal of these stocks

Stations cotieres et station hydrologique cotiere d'Abidjan: annees 1980-1981

Beach surface temperature is recorded every morning between 7h30 and 8h00 at each coastal station. On figure 2, 3, 4 and 5 it has been plotted daily variation and mean variation computed on 7, 15 and 30 days basis of sea surface temperature. However it seems that variations of dynamic height anomaly are reflecting more accurately the stages of the coastal upwelling than the sea surface temperature.

Station hydrologique de Vridi et stations cotières de 1989 à 1991

In this report, accurate data from coastal stations and from the Vridi hydrological station were gathered. The used experiments took place from 1989 to 1991.

Campagnes Chalci, Chalci 84-01 (du 17 au 25-01-84) et Chalci 84-02 (du 03 au 11-07-84): resultats des chalutages

This publication gives the results of bottom trawlings made during the cruises CHALCI 84-01 and CHALCI 84-02 by the oceanographic research vessel "Andre NIZERY" sur le plateau continental ivoirien.