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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.
41

Indirekt ledarskap i samtida konflikter : En enkätstudie om indirekt ledarskap i ett svenskt tillfälligt sammansatt förband i en extrem insatsmiljö

Jonsson, Lars January 2014 (has links)
Forskningsfältet som omfattar hur militärt indirekt ledarskap genomförs under påfrestande förhållanden och i extrema miljöer är mycket begränsat. Studiens syfte har därför varit att kartlägga indirekt ledarskap i ett svenskt förband som genomförde skarp insats i Afghanistan 2010. Studiens teori har utgjorts av en svensk preliminär hierarkisk top-down modell som beskriver hur indirekt ledarskap utförs. 220 respondenter har deltagit i enkätstudien som genomförts i tre nivåer, hög, mellanliggande och lägre organisatorisk nivå. Kvalitativ empiri kompletterar den kvantitativa empirin. Resultatet av studien innebär att det indirekta ledarskapet inte upplevdes koherent i den studerade miljön. Kontingentschefens bidrag till förbandets resultat, geografiska avstånd, olika ledningsstrukturer samt graden av utsatthet är aspekter som påverkar hur dennes indirekta ledarskap upplevdes av förbandet. Studiens bidrag till krigsvetenskapen och den militära professionen utgörs av att ny empiri tillförts med nya perspektiv som påverkar utövandet av indirekt ledarskap i denna typ av kontext. Perspektiv som skulle kunna adresseras en liknande framtida militär insats.
42

Aspekte der Langzeitspeicherung - Das Speicherungskonzept in MONARCH

Ziegler, Christoph 05 July 1999 (has links)
Es werden Probleme der Langzeitarchivierung diskutiert, sowohl aus Anwendersicht als auch Betreibersicht. Konkret wird das Speicherungskonzept von MONARCH vorgestellt, mit dem versucht wird, die aufgeworfenen Probleme der Langzeitarchivierung zu loesen.
43

Mykensk alabastron från SH IIIC : Den mykenska samhällsförändringen genom keramiken / Mycenaean alabastron from LH IIIC : The societal change of the Mycenaean culture through the study of pottery

Cassman, Julia January 2022 (has links)
Mycenean society on mainland Greece started to decline with the collapse of the palatial system during the 13th century BC. Following the collapse was a big change in the ceramic repertoire of the Aegean area, this new period was later named the post-palatial period or late helladic IIIC which was based on the types of ceramics found during the period. The changes in the societies of the Aegean can be seen in the ceramics, which is one of the best-preserved materials from Mycenaean society. The changes are believed to have had a major impact on both the production and consumption of ceramic containers, which can be seen in the styles that were typical of the Greek mainland, but also in the spatial distribution and the use of ceramics. The purpose of this study is to analyze a ceramic object (an alabastron) from Uppsala University Museum Gustavianums antiquities collection and through the study find out how the object fits into the changes that took place in Mycenaean society around 1200 BC. The essay and the questions are mainly based on the ceramic object analyzed in the main part of the essay, where the purpose is to document and then analyze the vessel's manufacture, function, shape, decoration and the context. In this essay, theory and method is based on Panofskys’ framework for studies of iconography and iconology.
44

Affective Response to Upper Body and Lower Body Exercise

Osorio, Shanelle J 01 January 2020 (has links)
More than one-half of university students in the United States and Canada are not active enough to gain health benefits. Enjoyment of exercise proposes a feasible solution to the absence of motivation surrounding physical activity. The purpose of this study is to compare the differences in reported enjoyment between upper and lower body cycling graded exercise to exhaustion (GXT). Seven university students (23 ± 3 years old; 26 ± 4 kg/m2) performed two randomized graded exercise tests on different days: one for upper body, one for lower body. Feeling Scale (FS) measured the affective response during exercise. Post-exercise enjoyment values were recorded 15 minutes after concluding GXT using the Physical Activity Enjoyment Scale (PACES), which has been shown to be a valid and reliable measure of physical activity enjoyment. Paired t-tests were used to evaluate mean differences between upper and lower body GXT enjoyment scores. Rank biserial correlations and Cohen's d values were used to evaluate effect size for the non-parametric and parametric analyses. Alpha level was set a priori at p < 0.05. Means and standard deviations were calculated for PACES, age, and BMI. No significant differences were found for enjoyment (p=0.162) between upper (104.3 ± 12.6) and lower-body cycling (97.8 ± 15.3). Notable effect sizes were found for the PACES Total and several subscales (Enjoy/Hate, Pleasant, and Contentment). No significant differences were found for the FS at ventilatory threshold (p=0.586) or at maximal aerobic power (p=0.670) between the upper and lower body GXT trials. More research is needed to explore exercise enjoyment across different exercise modes and provide a more particular evaluation of PACES subscales. Further research should aim to compare enjoyment levels across different physical activity levels (e.g., low, moderate, high), between sexes and within diverse populations.
45

Persistent organic pollutants (POPs) associated with a platinum mine in the Limpopo Province, South Africa / Ilse Jordaan

Jordaan, Ilse January 2005 (has links)
South Africa ratified the Stockholm Convention (SC), which became legally binding on 17 May 2004. This Convention targets 12 particularly toxic persistent organic pollutants (POPs) for virtual elimination. The Convention also requires parties to reduce the release of organochlorine pesticides and the intentionally- and unintentionally-produced POPs such as dioxins, furans and polychlorinated biphenyls (PCBs) (referred to as dioxin-like chemicals). Dioxins are a heterogeneous mixture of chlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) congeners. These substances were never intentionally produced but are produced as by-products of industrial processes (such as metallurgical processes and bleaching of paper pulp). They can also be formed during natural processes such as volcanic eruptions and forest fires. The largest contributor to releases of PCDD/Fs in the environment is incomplete combustion from waste incinerators leading to the unintentional production of these compounds. Polychlorinated biphenyls (PCBs) are used in transformers and capacitors, but can also be formed unintentionally during industrial and thermal processes. Dioxin-like chemicals (PCDD/Fs and/or PCBs) are classified as persistent because of the following characteristics: lipophilicity and hydrophobicity; resistance to photolytic, chemical and biological degradation and they are able to travel long distances. As South Africa is a semiarid region, POPs will be less prone to travel here because these substances favour colder regions with high soil organic matter. Fish, predatory birds, mammals (including humans) absorb high concentrations of POPs through the process of bio-concentration, leading to bio-accumulation of these substances in the fatty tissue. PCDD/Fs occur as unwanted trace contaminants in air, water, land, in residues and products (such as consumer goods e.g. paper and textiles). The distribution of these chemicals into various matrices is problematic since they cause damage to the environment and human health. These chemicals pose a threat to human health when found in high concentrations that may lead to acute hepatoxicity and dermal toxicity (chloracne). Long-term exposure to low concentrations of these substances might lead to chronic effects such as reproductive problems and carcinogenicity. Since ferrous and non-ferrous metal production is a source of dioxin-like chemicals, a platinum mine in the Limpopo Province, South Africa, was selected for this investigation. The aim of the study was to determine if there are dioxin-like chemicals associated with platinum mining and processing, and if the H4IIE reporter gene bio-assay could be used to semi-quantify and assess the potencies of the complex environmental and process samples by determining their Toxic Equivalency Quotients (TEQ). The implications of the sources to the formation of dioxin-like chemicals regarding the SC were investigated and recommendations were made to improve this study. Samples were collected from tailings dams, woodchips, a dumpsite and slag from the smelter at Union Section. Samples were extracted with the Soxhlet apparatus using hexane as solvent. The percentage total organic carbon (%TOC) was determined for each sample to normalise the data. The method used was the Walkley-Black method. In determining the TEQ of each sample, the H4IIE luc cell line was used. The cells of the H4IIE luc line are genetically modified rat hepatoma cells stably transfected with a luciferase firefly gene. The luciferase gene is activated by the presence of dioxin-like compounds and the concentration of the enzyme is measured as relative light units (RLUs). The amount of RLUs is directly proportional to the dioxin load in the extract. This method is rapid, cost and time-effective in determining the TEQ when compared to chemical analysis. The TEQ2o-valuesin the various samples, as determined with the H4IIE luc cell line, ranged from 0.007 ngTEQ/kg to 54.06 ngTEQ/kg. Thermal processes at the smelter, sorption of hydrophobic organic compounds (HOCs) to soil and tailings, and external sources such as anthropogenic activities contributed to high TEQ2o-values. Climatic conditions, wind, precipitation, and solubility of HOCs into surfactants lead to low TEQ20. The smelter at Union Section had a very high TEQ20of 44.62 ngTEQ/kg compared to Impala Platinum mine (5.15 ngTEQ/kg). This implies that workers at Union Section are possibly exposed to low and high concentrations of dioxin-like chemicals. Long-term exposure to these compounds could lead to bio-accumulation in the fatty tissue of the mine workers, leading to chronic effects such as reproductive problems and cancer. The air emission of the furnace at the smelter was 0.03 gTEQ/annum and the release of the PCDD/Fs into the slag was 0.60 gTEQ/annum. By effectively managing the smelter it is possible to reduce the TEQ. The TEQ of each sample increased due to normalising the data. The normalised TEQ20 ranged from 0.94 ng TEQ/kg to 42497.48 ngTEQ/kg. Dioxin-like chemicals are present on a platinum mine, but at varying quantities and the effects of these compounds might be detrimental to the environment and the workers at the platinum mine. Further analyses of the health impacts associated with the platinum mine are needed. The H4IIE reporter gene bio-assay could be used to effectively determine the TEQ of each sample. Although this investigation has identified the formation and presence of dioxin-like chemicals at certain stages of mining and processing, not all of the processes were investigated. Some of these processes have the potential to add, and even destroy, these chemicals, affecting potential human exposure and amounts released to the environment. This, however, requires further investigation. The financial assistance of the National Research Foundation (NRF) towards this research is hereby acknowledged. Opinions expressed and conclusions arrived at, are those of the author and are not necessarily to be attributed to the NRF. / Thesis (M. Environmental Science)--North-West University, Potchefstroom Campus, 2006.
46

Improved Assessment in Environmental Monitoring of POPs : Using monitoring data from the aquatic ecosystem and human milk

Nyberg, Elisabeth January 2016 (has links)
The thesis deals with several aspects of monitoring of persistent organic contaminants (POPs) in biological matrices, for example choice of sample, sampling design, and statistical treatment of data both for temporal and spatial trends and for compliance towards a set target value. The efficiency has been evaluated through statistical power analyses. Contaminant data from more than 4 decades from the Swedish National Monitoring Programs for monitoring of contaminants in biota (marine, freshwater and human health), has been quantitatively evaluated both temporally and spatially and for compliance. The aim was also to evaluate the suitability of different matrices, i.e. herring (Clupea harengus), guillemot (Uria aalge) egg, cod (Gadus morhua), perch (Perca fluviatilis), eelpout (Zoarces viviparous), blue mussel (Mytilus edulis), pike (Esox lucius), Arctic char (Salvelinus alpinus) and human milk, for monitoring of POPs with the overall aim to improve the assessment within monitoring programs. The results show that variation can be reduced by using pooled samples including more specimens but fewer chemical analyses, which in turn generate a higher statistical power to a lower cost, at least in cases where the cost of collection and sampling is considerably lower than the cost of chemical analysis. However, there are also a number of advantages using individual samples, such as information of sample variance and maximum value, which allows the choice of an appropriate central measure and direct adjustment of confounding factors. Generally, the levels of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) have decreased both in marine and freshwater biota but concentrations are still higher in the Baltic compared to e.g. the North Sea. The levels of dioxinlike-PCBs and polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/Fs) have decreased in human milk over time, but not to the same extent in fish and guillemot egg from the Baltic and the freshwater environment. This may be explained by the dietary advice developed by the Swedish Food Administration with the goal that girls, reproductive aged, and pregnant women should eat less food containing high levels of PCDD/Fs. Thus the levels in milk could continue to decrease at the same rate although the temporal trend in the environment has slowed down or leveled out. The most essential regarding the choice of species and matrices for contaminant monitoring, is that the species and organ fit the purpose of the monitoring.
47

Estudio de contaminantes orgánicos en el aprovechamiento de lodos de depuradora de aguas residuales urbanas

Gómez-Rico, María Francisca 03 March 2008 (has links)
D.L. A 792-2008 / Ministerio de Educación y Ciencia; Programa FEDER; Generalitat Valenciana; Universidad de Alicante.
48

Explosion coulombienne de H2 induite par une impulsion laser intense sub-10 fs

Saugout, Sébastien 05 December 2006 (has links) (PDF)
Ce travail de thèse a pour but l'étude expérimentale et théorique de l'interaction de la molécule H2 avec des impulsions laser de durée inférieure à 10fs. L'éjection des deux électrons de la molécule par le champ laser conduit à la fragmentation du système en deux protons. Ce processus est appelé explosion coulombienne. La mesure des spectres d'énergie cinétique des protons permet d'analyser les dynamiques électronique et nucléaire en fonction des différents paramètres laser. Ces dynamiques sont également analysées dans le cadre d'un modèle théorique non perturbatif, à deux électrons actifs, basé sur l'équation de Schrödinger dépendant du temps. Dans ce modèle, la distance internucléaire est traitée de façon quantique.<br /><br /><br />La complémentarité des résultats expérimentaux et théoriques permet de mettre en évidence la translation des spectres d'énergie cinétique vers les énergies plus élevées lorsque la durée de l'impulsion diminue. Cette étude est réalisée pour des impulsions dans la gamme de 40 à 10fs expérimentalement et jusqu'à 1fs théoriquement. Cette étude montre également que, pour des durées d'impulsion laser inférieures à 4fs, la phase absolue devient un paramètre essentiel à prendre en compte. En outre, la dynamique moléculaire de H2 en champ laser intense ultracourt est également sensible à la valeur de l'éclairement crête de l'impulsion. Les résultats théoriques et expérimentaux montrent que les spectres d'énergie sont centrés autour d'une énergie plus élevée quand l'éclairement augmente. Par ailleurs, deux régimes d'ionisation double sont également mis en évidence théoriquement pour des impulsions de 4fs. La sensibilité de H2 à la qualité temporelle de l'impulsion laser permet une détection, par l'intermédiaire des spectres expérimentaux d'énergie cinétique, des pré- ou post-impulsions susceptibles d'apparaître autour de l'impulsion laser principale. Enfin, les différents types d'ionisation double sont étudiés et les résultats mettent en évidence la dynamique électronique attoseconde de la recollision et l'influence de cette dernière sur la dynamique nucléaire femtoseconde.
49

Prickskytt i en lågintensiv konflikt : En undersökning av skillnaderna mellan den svenska prickskyttefunktionen i Sverige och Afghanistan / Sniper in a asymmetric conflict : An analysis of the difference between sniper operations in Sweden and Afghanistan

Christensson, Claes January 2011 (has links)
Med fokus på Sveriges insats i Afghanistan som är en asymmetrisk konflikt där konventionella stridskrafter möter en motståndare som består av talibaner och kriminella med medel och metoder som skiljer sig från en reguljär motståndare. Problemet som kan uppstå är att motståndaren gömmer sig bland civila och förmågan till precisionsbekämpning av mål samt informationsinhämtning för att identifiera motståndare från civila blir viktigt. Syftet med uppsatsen är att se hur funktionen nyttjas i Sverige av erfarna truppförare och trupputbildare som har stor erfarenhet av prickskyttefunktionen för att sedan jämföra med insatsen i Afghanistan, FS19, och försöka se möjligheter till utveckling av funktionen vid internationell insats. Metoden kommer vara en jämförande fallstudie av prickskyttefunktionen i Sverige och Afghanistan. Med inriktning mot fyra ämnesområden (psykologisk effekt, risker, funktion och organisation) kommer en enkät att besvaras av chefer från FS19 och Arméns Jägarbataljon. Resultatet från studien är att prickskyttefunktionen nyttjades väldigt sällan på FS19. Den främsta orsaken till att den inte nyttjades var de ökade riskerna detta medförde samt att cheferna på FS19 föredrog att nyttja dem som skarpskyttar. Slutsatserna efter genomförd undersökning är att för att prickskytten skall nyttjas enligt definitionen måste befattning utvecklas i utlandsstyrkan och befattning måste övas, både för att öva prickskytten själv men också för att chef ska få förtroende för skytten och vilken effekt denne kan uppnå. Vidare måste förmågan till Personnel Recovery öka vilket ger cheferna större möjlighet att nyttja funktionen, förutsatt att befattning är övad och anses duglig. / The essay was written by Claes Christensson, during his sixth and final semester atKarlbergMilitaryAcademy. The essay is an exam in the final course at theNationalDefenceCollege basic officers program. Before entering the program, Christensson served fifteen months conscription in Arvidsjaur at the Army Ranger Battalion (ARB). Christensson was a sniper squad leader and is himself also a trained sniper. Today the Swedish Armed Forces (SAF) takes part in different conflicts around the world. This essay focuses on the SAF contribution to the asymmetric conflict currently taking place inAfghanistan. In today’s conflicts where insurgents cannot fight using conventional warfare, other means and methods are instead used. A problem for COIN forces is the fact that insurgents hide among the civilian populace. A sniper can however, with high precision, both destroy enemy personnel or locate and distinguish insurgents from civilians. The purpose of this essay is to determine how snipers are being used by highly experienced officers when training at the ARB. These experiences will then be compared to how snipers are being utilised in the Swedish contribution to ISAF (called FS19) at the Provincial Reconstruction Team (PRT) in Mazar-i-Sharif in northernAfghanistanbetween April and October 2010. The method of this essay will be a comparison between the ARB and FS19. Commanders will be subjected to a questionnaire and answer a number of questions, based upon four subjects. The subjects are psychological effect, risks, function and organisation linked to the sniper concept. The result of this essay shows that snipers were not nearly as often being used during FS19 than during exercises at ARB. The apparent reason for this was the increased risk and that commanders from FS19 preferably used them as sharpshooters. Soldiers with sniper rifles were being used to destroy enemy personnel with high precision and to determine civilians from enemy personnel. The conclusions are that if snipers are to be used in the proper fashion, the dedicated posting needs to be implemented in the SAF contribution to ISAF. Moreover, both snipers and commanders need to train applicably to get the full understanding of the effects a sniper can have and to gain confidence in the sniper as a concept. Furthermore, the Personnel Recovery ability needs to improve so that commanders can utilise the sniper concept in high risk operations.
50

Eliminació de contaminants orgànics persistents d’oli de peix

Ortiz Almirall, Xavier 15 June 2011 (has links)
En la present tesi doctoral s’han estudiat diversos mètodes per a l’eliminació de contaminants orgànics persistents en olis de peix amb finalitat alimentària. S’han posat al punt les metodologies d’anàlisi necessàries per a la correcta determinació d’aquests compostos en la matriu d’estudi. S’han avaluat amb detall les etapes de purificació de la mostra, fraccionament dels analits i anàlisi instrumental. El mètode ha estat validat amb resultats satisfactoris, i s’ha comprovat el seu bon funcionament a través de la participació en diversos exercicis d’intercalibtage, així com la realització de diversos estudis amb mostres reals d’oli de peix. S’ha estudiat l’eliminació dels contaminants orgànics persistents a través d’adsorbents sòlids amb base silícica i carbonàcia. Les condicions experimentals han estat estudiades més a fons mitjançant dissenys d’experiències, per acabar optimitzant el mètode d’adsorció amb un disseny d’evolució. Els millors resultats s’han obtingut amb el carbó actiu, que mostra una elevada eficàcia en l’eliminació de PCDD/Fs, d-l PCBs i HCB. S’ha estudiat l’eliminació dels contaminants orgànics persistents mitjançant tècniques de degradació fotoquímiques. Inicialment s’ha fotodegradat cada família de contaminants per separat, per poder estudiar més a fons les condicions necessàries per la seva eliminació, així com els seus mecanismes i productes de degradació. Posteriorment s’ha estudiat la fotodegradació simultània dels analits d’interès en oli de peix. Aquesta tècnica s’ha mostrat efectiva en l’eliminació de DDT, PBDEs, HCB i PCBs similars a dioxines. Paral•lelament als estudis d’eliminació mitjançant adsorbents sòlids i tècniques fotoquímiques, s’ha comprovat la qualitat dels olis de peix abans i després del tractament. El procés d’adsorció en sòlids no afecta significativament a la qualitat de l’oli, mentre que les tècniques fotoquímiques degraden una part dels àcids grassos insaturats. S’ha estudiat l’eliminació de contaminants orgànics persistents en oli de peix mitjançant la combinació de les dues tècniques estudiades anteriorment, amb una primera etapa de degradació fotoquímica i una segona etapa d’adsorció. S’han comparat els resultats finals d’eliminació que s’obtenen amb cada un dels mètodes desenvolupats (adsorció, fotodegradació i combinat). L’adsorció en carbó actiu és el procés més adequat per l’eliminació de COPs en oli de peix. S’ha realitzat un estudi dels nivells diastereomèrics i enantiomèrics d’un contaminant emergent -l’hexabromociclododecà (HBCD)- en oli de peix. S’ha avaluat la seva eliminació de la matriu d’estudi mitjançant adsorbents amb base carbonàcia i degradació fotoquímica, sent principalment eliminat per aquesta segona via. / En la presente tesis doctoral se han estudiado diversos métodos para la eliminación de contaminantes orgánicos persistentes en aceites de pescado con finalidad alimentaria. Se han desarrollado los métodos de análisis necesarios para la correcta determinación de estos compuestos en la matriz de estudio. Se han evaluado con detalle las etapas de purificación de la muestra, fraccionamiento de los analitos y análisis instrumental. El método ha sido validado con resultados satisfactorios, y se ha comprobado su buen funcionamiento mediante ejercicios de intercalibraje, así como la realización de diversos estudios con muestras reales de aceite de pescado. Se ha estudiado la eliminación de los contaminantes persistentes mediante adsorbentes sólidos con base silícica y carbonacea. Las condiciones experimentales han estado estudiadas en profundidad mediante diseños de experiencias y de evolución. Los mejores resultados se han obtenido con carbón activo, que demuestra una elevada eficacia en la eliminación de PCDD/Fs, dl-PCBs y HCB. Se ha estudiado la eliminación de los contaminantes orgánicos persistentes mediante técnicas de degradación fotoquímica. Inicialmente se ha fotodegradado cada familia de contaminantes por separado, para poder estudiar más a fondo las condiciones necesarias para su eliminación. Posteriormente se ha estudiado la degradación simultánea de los analitos de interés en aceite de pescado. Esta técnica se ha mostrado efectiva en la eliminación de DDT, PBDEs, HCB y PCBs similares a dioxinas. Paralelamente a los estudios de eliminación mediante adsorbentes sólidos y técnicas fotoquímicas, se ha comprobado la calidad de los aceites de pescado antes y después del tratamiento. El proceso de adsorción en sólidos no afecta significativamente a la calidad del aceite, mientras que las técnicas fotoquímicas degradan una parte de los ácidos grasos insaturados. Se ha estudiado la eliminación de contaminantes orgánicos persistentes en aceites de pescado mediante la combinación de las dos técnicas estudiadas anteriormente, con una primera etapa de degradación fotoquímica y una segunda etapa de adsorción. Se han comparado los resultados finales de eliminación que se obtienen con cada uno de los métodos desarrollados. La adsorción en carbón activo es el proceso más adecuado para la eliminación de COPs en aceite de pescado. Se ha realizado un estudio de los niveles diastereoisoméricos y enantioméricos de un contaminante emergente –HBCD- en aceite de pescado. Se ha evaluado su capacidad de eliminación de la matriz de estudio mediante adsorbentes con base carbonacia y degradación fotoquímica, siendo principalmente eliminado por la segunda vía. / During the present doctoral thesis several methods for the elimination of persistent organic pollutants from fish oil have been studied. Analytical methodologies for the determination of these compounds in fish oil have been developed. Sample purification, fractionation of the analytes and instrumental determination steps have been deeply studied. The method has been validated with satisfactory results, and its performance has been verified through its participation in several intercalibration exercises and studies with real fish oil samples. Elimination of persistent organic pollutants with silicon and carbon-based adsorbents has been studied. The experimental conditions have been studied in depth with an experimental design, to finally optimize the adsorption method using an evolutionary design. Best results have been obtained with the active carbon, showing high efficiency of the removal of PCDD/Fs, dioxin-like PCBs and HCB. Elimination of persistent organic pollutants with photochemical degradation techniques has been studied. Initially, each family of pollutants has been photodegraded separately, to determine its degradation conditions, as well as degradation mechanisms and by-products. Later, simultaneous photodegradation of the analytes has been studied in fish oil. This technique has shown high efficiency on the degradation of DDT, PBDEs, HCB and dioxin-like PCBs. The quality of the oils before and after the treatments with solid adsorbents and photochemical degradation has also been studied. The adsorption process does not significantly affect the quality of the oils, while photochemical techniques can degrade the unsaturated fatty acids. Elimination of persistent organic pollutants in fish oil combining adsorption in solids and photochemical degradation has been studied. Results obtained with each of the developed methodologies (adsorption, photodegradation and combined method) were compared. Adsorption in active carbon is the most suitable process for COPs elimination in fish oil. Finally, diastereoisomeric and enantiomeric levels of an emerging pollutant –hexabromocyclododecane (HBCD)- in fish oil have been studied. Its elimination has been evaluated with carbon-based adsorbents and photochemical degradation, being mainly eliminated with the photodegradation techniques.

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