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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Hydrocarbons in the open ocean waters near the Galician Bank after the deep sea spill from the Prestige wrecks

Elordui-Zapatarietxe, Saioa 03 June 2009 (has links)
Hoy en día existe una escasez de estudios sobre la distribución de los hidrocarburos en mar abierto, aunque el aumento de la explotación de yacimientos de petróleo y la intensificación del tráfico marítimo más allá de la plataforma continental haya aumentado. Asimismo, se han identificado nuevas fuentes de contaminación. En los últimos años se ha puesto en evidencia el alto número de barcos hundidos en los fondos marinos que podrían potencialmente generar futuros vertidos de petróleo. En esta tesis, se investiga el accidente del petrolero Prestige cerca de Galicia en el 2002 como caso de estudio de un vertido marino en profundidad en mar abierto, ya que aproximadamente unas 43.000 toneladas de fuel oil pesado que llevaba a bordo fueron vertidas una vez el barco de rompió en dos y se hundió. Además, la zona del hundimiento del Prestige es un área hidrodinámicamente compleja. La columna de agua esta formada por cinco masas de aguas principales, de diferente origen y con características físico-químicas diferentes, que pueden contribuir activamente extender el fuel liberado por el Prestige en las aguas cerca del Banco de Galicia. En este contexto, el principal objetivo de la presente tesis ha sido determinar la importancia de los pecios del Prestige como fuente de contaminación en las aguas cerca del Banco de Galicia varios años después del accidente e investigar el papel de las masas de agua en el transporte y distribución de los hidrocarburos en la zona del hundimiento. Estos objetivos se han alcanzado mediante la combinación de estudios de laboratorio y trabajo de campo. Por un lado, se realizaron diferentes experimentos bajo condiciones estables de temperatura y salinidad que dieron información sobre la disolución potencial del fuel del Prestige en agua marina. Además, dos campañas oceanográficas se llevaros a cabo en marzo y octubre del 2006 cerca de los pecios y las zonas adyacentes, con el objetivo de recoger agua marina. Se determinaron hidrocarburos en la materia sólida en suspensión y la fase disuelta del agua en la columna de agua de las tres estaciones. Una se encontraba encima de los pecios del Prestige mientras que las otras dos se localizaron a 73 millas náuticas, una al norte y la otra al sur de este punto. En marzo del 2006, en la zona del hundimiento y en las otras dos estaciones, las concentraciones de hidrocarburos de origen petrogénico estaban dentro el rango los niveles descritos en la literatura para áreas similares, mientras que los niveles en octubre del mismo año era superiores. Las concentraciones de hidrocarburos poliaromáticos encontrados en la fase disuelta eran, tanto en marzo como en octubre, mucho mayores que los niveles de referencia establecidos para la zona. La huella química de los hidrocarburos en octubre del 2006 indicó que los pecios del Prestige habían estado liberando fuel oil durante varios años después del accidente. Sin embargo, a pesar de la amplia presencia de hidrocarburos provenientes del petróleo en la columna de agua de las tres estaciones, no se puede afirmar que el Prestige constituía la fuente más importante de contaminación en le área, ya que los hidrocarburos parecían provenir de múltiples orígenes. De hecho, varias masas de agua presentan contenidos distintivos de hidrocarburos en la fase disuelta y material particulado. El estudio realizado se puede entender como un ejemplo del potencial de un pecio hundido en el Noratlántico profundo como fuente de contaminación. Aunque cada pecio representa un caso único, el conocimiento obtenido sobre la distribución espacial y temporal de los hidrocarburos después del accidente del Prestige se puede utilizar en futuros vertidos. / There is an apparent shortage of studies on the distribution and fate of oil hydrocarbons in open ocean waters. Nevertheless, given the increasing exploitation of oilfields in the high seas, and the intensification of maritime traffic, in the last decades, oil pollution of the marine environment beyond the continental platforms is increasing. In addition, new sources of pollution are being recognized. Thus, in recent years it has been noted that the high number of sunken vessels scattered in the oceans sea floor are potentially a present and future source of oil spills. In this thesis, the accident of the Prestige tanker in 2002 off the Galician coast is investigated as a case study of a deep sea spill in open ocean waters, since around 43,000 tonnes of heavy fuel oil were spilled after the vessel broke in two and sank. In addition, the area near the Galician Bank, where the Prestige wrecks are located, is hydrodynamically complex. The water column is comprised by five main water masses from different origins and physico-chemical properties, which may contribute to actively spread the oil released from the Prestige in different and distinct ways. In this context, the main aim of this study has been to determine the importance of the Prestige shipwrecks as a source of oil pollution in the waters near the Galician Bank several years after the accident took place and to investigate the role of the water masses in the sinking area in the transport and distribution of hydrocarbons. These objectives have been tackled by a combination of laboratory and field studies. First of all, several sets of experiments were carried out under controlled temperature and salinity conditions which provided information about the potential dissolution of the Prestige fuel oil in seawater. In addition, two oceanographic cruises were undertaken in March and October 2006, near the wrecks location and surrounding areas, to collect seawater samples. Hydrocarbons were determined in the suspended particulate matter (SPM) and dissolved phase (DP) in the water column of three stations. One was located above the Prestige wrecks, and the other two 73 nautical miles north and south of the Prestige incident area.Hydrocarbons concentrations from petrogenic sources in the SPM above the wreck and surrounding areas in March 2006 were within the range of abundances previously reported for similar areas, but much higher in October 2006. The concentrations of polycyclic aromatic hydrocarbons found in the DP were, both in March and October 2006, well above any expected background levels. The chemical fingerprint of the hydrocarbons indicated that in October 2006 the oil at the Prestige station originated from the wrecks. This, together with the unusually high relative concentration of hydrocarbons in the DP at the Prestige station in March 2006, indicates that the Prestige wrecks had been releasing oil for several years after the accident. However, despite the widespread occurrence of oil hydrocarbons in the three stations and throughout their water columns, it could not be concluded that the Prestige was the main source of pollution in the area near the Galician bank, which most likely has multiple origins. In fact, different water masses contain distinct contents of hydrocarbons in the SPM and the DP, which in some instances may have remote sources. The study conducted can be viewed as an example of the potential of a sunken wreck in the deep North Atlantic as a source of pollution. Although each potentially polluting shipwreck represents a singular case, knowledge obtained about the temporal and spatial distribution of hydrocarbons after the accident of the Prestige could be applied to deal with other deep spills in the future.
32

Stability and instability : hierarchy, authority, and archaeologists in China /

Evasdottir, Erika Emma Sandra. January 2000 (has links)
Th.--Anthropology--Harvard university, Graduate school of arts and sciences, 2000. / Bibliogr. p. 351-357. Glossaire.
33

El mérito y la estrategia : clérigos, juristas y médicos en Nueva España /

Aguirre Salvador, Rodolfo. January 2003 (has links)
Texte remanié de: Tesis doctoral--Facultad de filosofía y letras--Universidad nacional autónoma de México, 2000. Titre de soutenance : Universidad y sociedad : los graduados de la Nueva España en el siglo XVIII. / Bibliogr. p. 569-586.
34

Reputation transfer to enter new B-to-B markets measuring and modelling approaches

Falkenreck, Christine January 2009 (has links)
Zugl.: Kassel, Univ., Diss., 2009 u.d.T.: Falkenreck, Christine: Impact on reputation and reputation transfer in international direct marketing
35

Measuring journal quality : developing a multi-item measure and investigating its usefulness in marketing

Hirst, Andrew S. January 1999 (has links)
The research journal especially in marketing, is now not only the primary communication method, but is also used to evaluate an academic's research contribution. Measuring the quality of research journals has also become more complex as a result of the rapid increase in the number of journals published. In marketing research, scientists have professed the use of sophisticated or more sensitive techniques yet little has been done to improve the measurement of research journals. This thesis investigates the use of alternative measurement techniques to explore this important aspect of the academic environment. Historically two dominant methodologies have been used to measure the quality ofjournals: Peer review and Citation Analysis. However these methods have been criticised and academics have been sceptical of the results, taking the opinion that these methods create, bias in the results. Previous methods have also taken a one-dimensional view of journal quality with little time devoted to uncovering the criteria that governs that quality. The research applied marketing methodologies that combined qualitative and quantitative research techniques to explore the problem. Four critical research questions were examined in this study. What are the important elements of journal research standing? 38 items were found to be important elements ofjoumal research standing. Is journal research standing a multi-dimensional construct? Three underlying dimensions represented the construct journal research standing, these were Reputation, Reviewing Standards and Content Quality. Do academics acknowledge the multiple dimensions of journal research standing? Academics acknowledged the -differences -between dimensions for ten selected marketing journals. What moderating factors affect academic opinions of journal research standing? Academic attitudes towards a joutnal's research stdtiding are moderated by their country of origin, familiarity and research fit. Attitudes towards a journal may also be moderated when academics have a paper rejected from that particular journal.
36

The tiger's leap the Korean drive for national prestige and world approval /

Noerper, Stephen Eric. January 1993 (has links)
Thesis (Ph. D.)--Fletcher School of Law and Diplomacy, 1993. / Vita. Includes bibliographical references (leaves 271-281).
37

Family social position and school expectations as factors influencing the peer group status of fifth-and-sixth-grade elementary school children

Doran, Joseph Thomas. January 1963 (has links)
Thesis (Ph. D.)--University of Notre Dame, June, 1963. / Vita. Bibliography: l. 198-203.
38

The Mediatised Capitalists A European Perspective on how Journalists perceive the Role of the Private Equity Industry /

Alhanko, Diane. January 2007 (has links) (PDF)
Master-Arbeit Univ. St. Gallen, 2007.
39

Die Schnittstelle von Recht und Kommunikation Das Phänomen Reputation. Eine rechtliche und ökonomische Einordnung /

Bachmann, David Matthias. January 2008 (has links) (PDF)
Master-Arbeit Univ. St. Gallen, 2008.
40

Ökologische Nachhaltigkeitspolitik und Reputationssicherung bei Schweizer Grossbanken Können die beiden Schweizer Grossbanken Credit Suisse und UBS mit ihrem ökologischen Engagement eine Reputationschance verwirklichen? /

Huber, Myriam Céline. January 2008 (has links) (PDF)
Master-Arbeit Univ. St. Gallen, 2008.

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