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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.
1

Investigation of the distribution of alkylphenol and alkylphenol polyethoxylates in main rivers and harbor areas of Kaohsiung city by LC-MS/MS

Chen, Jen-kun 04 September 2006 (has links)
Hou-Chin stream, Love river, and Chien-Chen river, the three main rivers in Kaohsiung city, flow through the populous residential and industrial areas. A large portion of sewage from domestic and industrial sources are discharged into these rivers, then the Love river and Chien-Chen river pour into the harbor area. In order to understand the pollution of alkylphenol polyethoxylates in these areas, water and sediment samples in Hou-Chin stream, Love river, Chien-Chen river and harbor area in Kaohsiung city were collected and the contents of alkylphenol and corresponding polyethoxylates were analyzed in this study. LC/MS/MS was used as the analytical instrument which is relatively time-saving in comparison with other instruments. It is also more convenient due to the facts that no derivation or colorization are needed in sample pretreatment. The detection limit can reach to 0.03 ng/ml and recovery can be around 83.6~91.6%. It can analyze alkylphenols combinded with long ethoxylate chain with improved sensitivity and selectivity. In the four sampling areas, the concentration of NPs in water were between 7.4~241.8ng/ml, and OPs were between 0.66~64.2ng/ml. The most contaminated water samples were found at Chih-Ping Bridge on the mainstream of Love river and Pau-Chu-Kou Dam Station and Min-Tsu Bridge on the tributary of Love river where the concentrations of NPs were greater than 200ng/ml, OPs were greater than 30ng/ml. We found that the main pollution sources were from Lung-Hsin Bridge, Tzu-Yu Bridge, Lung -Hua Bridge, and Pau-Chu-Kou Dam Station. The pollution sources of the Chien-Chen river were mainly from Chung-An Bridge and Chen-Chuan Bridge. Concentration of NPs in upper sediments were between 633.1~2113.8ng/g, OPs were between 50.3~287.9ng/g. The highest concentration of NPs was at Ho-Ti Bridge on the mainstream of Love river, and the lowest concentration of NPs was at Chung-An Bridge on Chien-Chen river. The highest concentration of OPs was at Chen-Chuan Bridge in Chien-Chen river, and the lowest concentration of OPs was Min-Tsu Bridge on the tributary of Love river. The concentration of NPs in deeper sediments were between 523.9~1919.5ng/g, OPs were between 39.9~322.0ng/g. The highest concentration of NPs was at Chung-Hua Bridge on the tributary of Lover river, and the lowest concentration of NPs was at Chung-An Bridge on Chien-Chen river. The highest concentration of OPs was at Chi-Chin Fishing Port, and the lowest concentration of OPs was at Min-Tsu Bridge on the tributary of Love river. The salinity of water samples and the total organic carbon in sediment sample will influence the distribution coefficient of alkylphenol polyethoxylates with different length of ethoxylate chains, their distribution coefficients were between 0.48~2.67. In comparison with foreign studies, the concentrations of alkylphenol polyethoxylates of water and sediments amples in this study were between the highest and lowest values reported. However, the observed concentrations of alkylphenols in these study areas were higher then other rivers in Taiwan. These values were higher than the Probable No Effect Concentrations ( PNEC) of NP risk assessed by European Union. It can be concluded that the pollution of alkylphenol polyethoxylates of water and sediment is getting more serious in Hou-Chin stream, Love river, Chien-Chen river and harbor area in Kaohsiung city.
2

Investigation of alkylphenol polyethoxylates in the aquatic environment of Hengchun peninsula

Chao, Ching-hung 07 September 2012 (has links)
In April and June 2012, environmental water samples were collected from fourteen sampling sites in Hengchun peninsula to investigate the contents of alkylphenol polyethoxylates. A solid phase extraction combined with LC-MS/MS method for the analysis of alkylphenol polyethoxylates in environmental waters was developed in this study. The mobile phase used methanol gradient elution with deionized water. The recovery of nonylphenol polyethoxylate and octylphenol polyethoxylate were 68~94 % and 65~93 %, limit of detection were 1.89~54.20 ng/L and 0.44~39.31 ng/L, limit of quantitative were 6.29~181 ng/L and 1.48~131 ng/L. The SsuChung river contents of NPEO and OPEO were 15.64~36.29 £gg/L and 3.14~7.37 £gg/L. The Paoli river contents of NPEO and OPEO were 16.65~76.41 £gg/L and 5.66~18.80 £gg/L. The Hou Bay contents of NPEO and OPEO were 34.79~66.72 £gg/L and 7.77~19.03 £gg/L. The Shihniou river contents of NPEO and OPEO were 26.67 £gg/L and 6.68 £gg/L. The Wanli Tong, Baisha, Houbi Lake, South Bay, Caesar and Siangjiao Bay contents of NPEO and OPEO were 14.17~48.82 £gg/L and 3.88~14.79 £gg/L. The dry season concentration contents of alkylphenol polyethoxylates were high than the wet season. The concentration of nonylphenol polyethoxylate was higher than that of octylphenol polyehtoxylate.
3

Les substances émergentes dans les écosystèmes aquatiques français : une application aux alkylphénol-polyéthoxylés et aux substances pharmaceutiques

Lardy-Fontan, Sophie 09 December 2008 (has links)
Les alkylphénol-polyéthoxylés et les substances pharmaceutiques appartiennent à la classe des contaminants émergents qui sont depuis peu étudiés dans les milieux naturels. Ces composés d’usage très répandu (aussi bien en termes d’applications qu’en termes de quantité) sont introduits dans le milieu aquatique, via les stations d’épuration, principalement et sont susceptibles d’engendrer des effets toxiques sur les organismes vivants dans ces milieux. La première partie de ce travail de thèse a consisté en le développement et la validation de différentes méthodologies d’échantillonnage (ponctuel et intégratif (POCIS)), de différents protocoles d’extraction (SPE, extraction assistée par micro-ondes) et d’analyse (CL/SM, CL/SM/SM), nécessaires pour un dosage fiable des alkylphénol-polyéthoxylés et des substances pharmaceutiques dans les différents compartiments des systèmes aquatiques (phases dissoute, particulaire et sédimentaire, organismes biologiques). Ensuite, un bilan de la contamination de différents systèmes aquatiques (le bassin de d’estuaire de Seine, la Garonne et la Gironde, la baie de la Vilaine, la baie de l’Authie, l’Adour, la rade de Marseille) a été dressé. Une contamination généralisée par ces composés a été mise en évidence pour l’ensemble des sites étudiés. Les concentrations mesurées apparaissent extrêmement variables selon la classe de molécule considérée, les sites et le temps avec des concentrations comprises entre le ng.l-1 et la dizaine de µg.l-1 pour les phases dissoutes et de la dizaine de ng.g-1 et la dizaine de µg.g-1 pour les phases solides (plusieurs centaines de µg.g-1 dans les boues d’épuration). Ces études ont également permis de documenter la présence et le devenir des molécules ciblées dans les stations d’épuration et ont permis d’en évaluer l’efficacité quant l’abattement des substances incriminées. Enfin, ces travaux ont également permis de mettre en évidence des phénomènes de partition entre les phases dissoutes et les phases solides ainsi que des phénomènes de transferts vers les organismes du milieu. / Alkylphenol-polyethoxylates and pharmaceutical substances belong to the class of the emerging contaminants which have been recently studied in natural environments. These compounds of very widespread use (in terms of applications as well as in terms of quantity) are introduced into the aquatic environment, via the wastewater treatment plants, mainly, and are likely to generate toxic effects on the living organisms in these systems. The first part of this work consisted in the development and validation of various methodologies of sampling (grab sampling and integrative sampling (POCIS)), of various protocols of extraction (SPE, microwaves assisted extraction) and of analysis (LC/MS, LC/MS/MS), necessary for a reliable quantification of alkylphenol-polyethoxylates and pharmaceutical substances in the various compartments of aquatic systems (phases dissolved, particulate and sedimentary, biological organisms). Then, an assessment of the contamination of numerous aquatic systems (the catchment area of the Seine estuary, the Garonne and the Gironde, the bay of Vilaine, the bay of Authie, the Adour, the Mediterranean coast of Marseilles) was undertaken. A generalized contamination by these compounds was highlighted for all the studied sites. The measured concentrations appear to be extremely variable according to the class of molecule considered, the sites and time with concentrations ranging from the ng.l-1 to tens of µg.l-1 for the dissolved phases and from tens of ng.g-1 to tens of µg.g-1 for the solid phases (several hundreds of µg.g-1 in the clarification sludge). These studies also made it possible to document the presence and the fate of these molecules in the French wastewater treatment plant and made it possible to evaluate their effectiveness to remove the studied compounds. Lastly, this work also made it possible to highlight phenomena of partition between the dissolved phases and the solid phases as well as phenomena of transfers through the biological organisms.

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