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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

Determination of Alkylphenol and Alkylphenol Polyethoxylates in Water and Sediments by Liquid Chromatography Tandem Mass Spectrometry

Cho, Chun-Liang 30 August 2010 (has links)
Alkylphenol polyethoxylates are one of the most importantclasses of nonionic surfactants. They are widely used in the household detergents and dyeing industry. Indeed, alkylphenols have been estimated that they are persistence organic pollutions which are not easily biodegraded by microorganisms and demonstrated as endocrine disruptors. Therefore alkylphenols regard as environmental hormones. The purpose in this research is developing the method which can be used for detection and quantification of alkylphenols and alkylphenol polyethoxylates in waters and sediments. LC-MS/MS was used as the analytical instrument which can analyze alkylphenols combined with long ethoxylate chain with improved sensitivity and selectivity. The extraction is liquid-liquid extraction. The mobile phase consisting of acetonitrile, water and methanol(43/14/43%, v/v/v) with 20mM ammonium acetate added was used for HPLC separation. The recoveries of alkylphenols and alkylphenol polyethoxylates from water and sediments were 83.0~95.1% and 84.8~94.6%. Decision limit(CC£\) and detection capability(CC£]) of water were 0.10~1.65 ng/L and 0.13~2.03 ng/L. CC£\ and CC£] of sediments were 0.05~0.95 ng/g and 0.06~1.18 ng/g.
2

Determination of alkylphenol polyethoxylates in environmental water by liquid chromatography-tandem mass spectrometry

Lan, Yi-wen 19 August 2011 (has links)
A LC-MS/MS method for the analysis of alkylphenol polyethoxylates in environmental waters was developed in this study. Preatment procedures including liquid-liquid extraction and solid phase extraction were compared, it¡¦s concluded that solid phase extraction is the more suitable way due to higher recovery and better stability for the analytical results. The recovery of nonylphenol polyethoxylate and octylphenol polyethoxylate were 62.3-110.7 % and 64.9-112.0 %, limit of detection were 17.60-174.9 ng/L and 7.40-53.56 ng/L. Enviromental water samples were collected from eight sampling sites along Love River in Kaohsiung City to investigate the contents of alkylphenol polyethoxylates. The highest concentration of total alkylphenol polyethoxylates was observed at Ming-Cheng Bridge which located at the upstream of Love River. For all of the analyzed compounds, the concentration of octylphenol tetraethoxylate (40.46 £gg/L) was the highest in all of the sampling sites. It¡¦s also noticed the concentration of octylphenol polyethoxylate (20.11 £gg/L) was higher than that of nonylphenol polyehtoxylate (128.04 £gg/L).
3

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.

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