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131.
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Tárraga Marta Garcia Alicia Ortiz Ramon Abella Rafael Peña Javier 《Natural Hazards》2001,23(2-3):417-429
A new satellite communication system specificallydesigned for low-rate data applications has beendeveloped and prototyped. A validation project isproposed to install a pilot network to be operated for6 months. One of the target markets related tovolcanoes, has been selected, so that a group of usersis integrated in the project. A specific applicationfor this market will be developed regarding dataacquisition, processing, storage and dissemination todistant users. The feasibility of using the newsatellite system to provide a new Eutelsat service forlow-rate data applications, will be evaluated from theperformance of the pilot network. The system ofautomatic acquisition, field storage and communicationwith the local control center is already functioning,as well as the circulation of information viaInternet. The development of the application andtransmission via satellite to distant users is stillin an evaluation phase for the volcanoes of Timanfaya(Lanzarote, Canary Island), Vesuvius (Naples) and SeteCidades Caldera (Sao Miguel, Azores Islands). 相似文献
133.
José Luis Sánchez-Hernández Javier Aparicio-Amador José Luis Alonso-Santos 《Geoforum》2010,41(3):469-478
This article draws on the theory of conventions and the concept of worlds of production for an interpretation of the transformations of a regional production system over several decades. Wine production in the Spanish region of Castile and Leon has shifted from a world of local and interpersonal production (prevailing before 1960) to the current preferred orientation towards quality markets, having passed through an intermediate phase (1960-1980) of table and bulk wines industrial production. Recently, indications have appeared of a return to an interpersonal and neo-artisanal production on the part of prestigious winemakers who distribute their wines to selected international clients. This path is the result of a gradual modification of the dominant conventions of the business, which has experienced a spectacular development in Castile and Leon, whose wines are now appreciated in many foreign markets. This evolution of conventions may be interpreted as an innovative process maintained to challenge the trends and demands of the market. But this argument does not explain how conventions change and how these changes spread along the production chain. Therefore, this article discusses the contribution of three factors to this shift across different worlds of wine production: organization of the production chain; regulations regarding the protection of food differentiated according to its geographic origin; and the setting up of a regional innovation system which supports the wine sector. 相似文献
134.
We present results of a rock‐magnetic study of soils that were affected by wildfires that burned portions of the Everglades in the Spring of 2008. Soils at sites that were extensively burned exhibit a pronounced surface magnetic enhancement effect with magnetizations of surface samples up to 16 times greater than that observed at depth (>7 cm) at these sites. The increase in magnetization results from an increased abundance of a low‐coercivity phase (maghemite) that occurs at the expense of the abundance of a high‐coercivity phase (goethite). These results indicate that fire‐induced heating caused goethite in the surface soils to convert into a more magnetic, low‐coercivity phase, such as maghemite. Goethite is an excellent adsorber of phosphorus, and therefore we hypothesize that the destruction of goethite as a result of burning may have important implications for phosphorus cycling in the Everglades ecosystem. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Padel Maxime Álvaro J. Javier Casas Josep Maria Clausen Sébastien Poujol Marc Sánchez-García Teresa 《International Journal of Earth Sciences》2018,107(5):1579-1601
International Journal of Earth Sciences - The volcanism hosted by the Ediacaran–Terreneuvian Canaveilles Group of the Eastern Pyrenees displays two distinct geochemical affinities: (1)... 相似文献
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José R. Martínez Catalán Ricardo Arenas Jacobo Abati Sonia Sánchez Martínez Florentino Díaz García Javier Fernández Suárez Pablo González Cuadra Pedro Castiñeiras Juan Gómez Barreiro Alejandro Díez Montes Emilio González Clavijo Francisco J. Rubio Pascual Pilar Andonaegui Teresa E. Jeffries James E. Alcock Rubén Díez Fernández Alicia López Carmona 《Comptes Rendus Geoscience》2009,341(2-3):114-126
Ophiolites of different Paleozoic ages occur in North-West (NW) Iberia in a rootless suture representing the remnants of the Rheic Ocean. Associated allochthonous terranes in the hanging- and foot-walls of the suture derive from the former margins, whereas the relative autochthon corresponds to the Paleozoic passive margin of northern Gondwana. The Paleozoic tectonic evolution of this part of the circum-Atlantic region is deduced from the stratigraphical, petrological, structural and metamorphic evolution of the different units and their ages. The tectonic reconstruction covers from Cambro-Ordovician continental rifting and the opening of the Rheic Ocean to its Middle to Upper Devonian closure. Then, the Variscan Laurussia–Gondwana convergence and collision is briefly described, from its onset to the late stages of collapse associated with the demise of the orogenic roots. 相似文献
140.
Kelsey D. Hargrove Michael S. Kelley Humberto Campins Javier Licandro Josh Emery 《Icarus》2012,221(1):453-455
We find a clear diversity in the 3 μm and 10 μm features of three Cybele asteroids: (107) Camilla, (121) Hermione, and (65) Cybele. (121) Hermione exhibits a “check-like” 3 μm feature, which may be attributed to OH-dominated minerals and (107) Camilla shows a rounded “bowl” like feature closer to that of (65) Cybele, which may be attributed to H2O-dominated minerals. The 10 μm features of these three asteroids are also different from each other. 相似文献