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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.
131

“Den här sommaren blir inte en vanlig sommar” : En jämförande fallstudie om oljeutsläppet från passagerarfartyget Marco Polo i Pukaviksbukten, 2023. / “This summer won't be a normal summer” : A comparative case study about the oil spill from the passenger ship Marco Polo in Pukaviksbukten, 2023.

Isaksson, Sandra, Persson, Katja, Flodin, Maria January 2024 (has links)
Denna studie syftar på att undersöka hur Sveriges myndigheter arbetar med krishantering med fokus på oljeutsläpp till havs. Tidigare forskning visar att Sverige har ett fungerande nätverk när det kommer till krishantering (Pålsson m.fl. 2018), men i det tvärsektionella arbetet brister Sverige i sin hantering. En definierad och strukturerad ledningskultur behövs för att spara tid, för att undvika okunskap och felinformation vid krishantering som exempelvis vid oljeutsläpp. Genom innehållsanalyser av utvärderingar från två tidigare oljepåslag, Fu Shan Hai i Ystad, 2003 och Golden Trader i Tjörn, 2011 samt semistrukturerade intervjuer med berörda aktörer vid händelsen av Marco Polo’s grundstötningar i Sölvesborg, 2023 har processerna analyserats och jämförts. Med berörda aktörer syftar denna studie på myndigheter, kommuner och organisationer som verkar och samarbetar runt händelser som exempelvis oljeutsläpp. Genom en sammanvägd analys kom det fram att samverkan i händelsen med Marco Polo har förbättrats, dock förekommer brister inom kommunikation och statlig satsning för krishantering till havs, och behöver utvecklas vidare. / This study aims to examine how Swedish authorities work with crisis management, with a focus on oil spills at sea. Previous research indicates that Sweden has an effective network for crisis management (Pålsson et al., 2018), but shortcomings exist in its cross-sectional work. A defined and structured leadership culture is needed to save time, and to avoid ignorance and misinformation during crisis management, such as in the event of oil spills. By conducting content analyses of evaluations from two previous oil spills, Fu Shan Hai in Ystad, 2003, and Golden Trader in Tjörn, 2011, as well as semi-structured interviews with relevant stakeholders involved in the Marco Polo grounding in Sölvesborg, 2023, the processes were analyzed and compared. By relevant stakeholders, this study refers to authorities, municipalities, and organizations that operate and collaborate around events such as oil spills. The comprehensive analysis revealed that cooperation during the Marco Polo incident has improved; however, deficiencies in communication and state investment in maritime crisis management persist and need further development.
132

Étude de la contamination de la côte libanaise par les hydrocarbures aromatiques polycycliques (HAPs) et les éléments traces métalliques (ETMs) : archives sédimentaires et biomonitoring suite à une marée noire / Study of the contamination of the Lebanese coast by polycyclic aromatic hydrocarbons (PAH) and trace metals (TM) : sedimentary archives and biomonitoring following oil spill

Azoury, Sabine 25 January 2013 (has links)
Ce projet de recherche porte sur l’étude de la contamination de la côte libanaise par les composés organiques (HAP, DDE) et par les éléments-trace métalliques (Hg, Pb principalement). Les travaux sur les compartiments sédimentaires et biologiques de la côte libanaise constituent deux parties aux problématiques et aux approches distinctes autour desquelles s’articule cette thèse. Dans la première partie, l’analyse d’une carotte sédimentaire datée prélevée sur le plateau continental du Sud du Liban a permis de reconstituer l’historique de contamination dans le bassin Levantin. Les analyses de contaminants dans les sédiments de la carotte C1 combinés à la datation aux 210Pb et 137Cs ont permis d’obtenir un enregistrement fiable des variations du dépôt de mercure, de plomb et de HAP sur le plateau continental libanais, dans le bassin Levantin. Bien que les concentrations et les flux soient relativement faibles, une augmentation en deux phases des concentrations est bien mise en évidence par le profil sédimentaire de C1. Le charbon est identifié comme source principale de Pb, de Hg et de HAP dans le bassin Levantin entre la moitié du 19ème siècle et la moitié du 20ème siècle. Les résultats des ratios isotopiques du Pb et des ratios diagnostiques de HAP appuient ce constat. Les archives sédimentaires dans la carotte C1 fournissent un signal du dépôt de contaminants à l’échelle globale probablement lié aux sources d’émissions atmosphériques en provenance d’Europe Centrale et de l’Est. Dans la seconde partie, une étude de la contamination par les HAP du littoral libanais est menée suite à la marée noire résultant du conflit armé israélo-libanais en 2006. Une approche de biomonitoring sur trois ans utilisant l’espèce de moules invasives Brachidontes variabilis a été développée. Les résultats indiquent une décroissance progressive des concentrations de HAP dans l’écosystème intertidal du littoral libanais. La contamination par les HAP du fioul en zone subtidale en 2007 est nettement plus faible. Cependant la signature des HAP dans les tissus de moules prélevées trois ans après la marée noire indique toujours la présence des composés du fioul de Jiyeh. La contamination est particulièrement persistante dans certaines zones fortement touchées par la nappe de fioul en 2006. Il apparaît que l’état initial pré-marée noire n’a pas été atteint, même trois ans après la marée noire de Jiyeh. L’examen détaillé de l’évolution spatiale et temporelle de la contamination par les HAP de l’environnement intertidal est présenté dans ce volet de notre étude. / This research project aims at the study of the contamination of the Lebanese coast by PAHs, DDE, Hg and Pb. The research work is divided into two distinct parts concerning two environmental compartments (sedimentary and biological) and it addresses different questions and approaches. In the first part, the study of a dated sediment core raised from the continental shelf in southern Lebanese coast allowed reconstructing the contamination history in the Levantine basin. The contaminants’ analysis as well as 210Pb and 137Cs datation allowed obtaining a reliable record of mercury, lead and PAHs sedimentary deposition in the Lebanese continental margin in the Levantine basin. Although concentrations and fluxes are relatively low, a two-phase increase of concentration is found using C1 core sedimentary profiles. Coal was identified as the main source of Pb, Hg and PAHs in the Levantine basin between the mid 19th and the mid 20th century. Ratios of Pb stable isotopes and PAH diagnostic ratios support this assumption. The studied sedimentary archives provide also information on the deposition of contaminants on a global scale possibly related to atmospheric emissions mainly from Central and Eastern Europe. In the second part of the thesis, the study of contamination by PAHs of the Lebanese coast was undertaken following an oil spill in the south of Lebanon, which occurred after the bombardment by the Israeli military of the electric power plant in Jiyeh in 2006. We have set-up a biomonitoring program with an invasive mussel specie Brachidontes variabilis over a three-year study. Results indicate a progressive decrease of PAH concentrations in the intertidal ecosystem of the Lebanese coast. Contamination of the subtidal zone in 2007 by Jiyeh fuel oil was significantly lower. However, Jiyeh fuel oil signature was still detectable in mussel tissues even three years after the oil spill. Contamination was found to be particularly persistent in some of the highly oiled sites. It appears that pre-spill state was still not reached even three years following the oil spill. Detailed investigation of spatio-temporal changes of intertidal mussels contamination by PAH is also presented in this part of the thesis.
133

Analytical method development for the identification, detection, and quantification of emerging environmental contaminants in complex matrices

Place, Benjamin J. 15 August 2013 (has links)
The development of analytical methods for emerging contaminants creates many unique challenges for analytical chemists. By their nature, emerging contaminants have inherent data gaps related to their environmental occurrence, fate, and impact. This dissertation is a compilation of three studies related to method development for the structural identification of emerging contaminants, the detection and quantification of chemicals used in unprecedented quantities and applications, and the extraction of compounds from complex matrices where the solvent-solute-matrix interactions are not completely understood. The three studies present analytical methods developed for emerging contaminants in complex matrices, including: fluorochemical surfactants in aqueous film-forming foams, oil dispersant surfactants in seawater, and fullerene nanomaterials in carbonaceous solids. Aqueous film-forming foams, used in military and commercial firefighting, represent environmentally-relevant commercial mixtures that contain a variety of fluorochemical surfactants. Combining the surfactant-selective ionization of fast atom bombardment mass spectrometry with high resolution mass spectrometry, chemical formulas for 11 different fluorochemical classes were identified. Then AFFF-related patents were used to determine the structures. Of the eleven classes of fluorochemicals, ten have little, if any, data on their environmental occurrence, fate, and potential impacts in the peer-reviewed literature. In addition, nine of the identified classes had either cationic or zwitterionic functionalities and are likely to have different transport properties compared to the well-studied anionic fluorochemicals, such as perfluorooctanoate. After the Deepwater Horizon oil spill in the summer of 2010, one of the emergency response methods for the mitigation of the oil's environmental impact was the use of unprecedented amounts of oil dispersant to break down the oil slick and encourage biodegradation. This event illustrated the need for rapid analytical method development in order to respond to the potential environmental disaster in a timely manner. Using large volume injection liquid chromatography with tandem mass spectrometry, an analytical method was developed for the trace analysis of the multiple dispersant surfactant classes and the potential degradation products of the primary surfactant. Limits of detection ranged from 49 ��� 3,000 ng/L. The method provided excellent recovery (86 ��� 119%) and precision (10 ��� 23% RSD), while also accommodating for the high salinity of seawater samples and analyte contamination. Despite the fact that fullerene nanomaterials have been studied for almost three decades, research is still being conducted to fully understand the environmental properties of these materials. Previous studies to extract fullerenes from environmental matrices have resulted in low efficiency, high variability, or the extraction efficiencies have gone unreported. Extraction by ultrasonication with toluene and 1-methylnaphthalene increased the recovery 5-fold of a spiked, isotopically-labeled C������ surrogate from carbon lampblack as compared to that of the conventional approach of extracting with 100% toluene. The study revealed the importance of evaluating experimental variables such as extraction solvent composition and volume, and sample mass, as they have a significant impact on the quantitative extraction of fullerenes from environmental matrices. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Aug. 15, 2012 - Aug. 15, 2013

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