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Atmospheric concentrations, depositi...

Correa, Oscar E.

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Atmospheric concentrations, deposition and modeling of polychlorinated dibenzo-p-dioxins and dibenzofurans.

紀錄類型:	書目-語言資料,印刷品 : Monograph/item
正題名/作者:	Atmospheric concentrations, deposition and modeling of polychlorinated dibenzo-p-dioxins and dibenzofurans./
作者:	Correa, Oscar E.
面頁冊數:	195 p.
附註:	Adviser: Hanadi S. Rifai.
Contained By:	Dissertation Abstracts International67-07B.
標題:	Atmospheric Sciences. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3225003
ISBN:	9780542781766

Atmospheric concentrations, deposition and modeling of polychlorinated dibenzo-p-dioxins and dibenzofurans.
Correa, Oscar E.

Atmospheric concentrations, deposition and modeling of polychlorinated dibenzo-p-dioxins and dibenzofurans. - 195 p.

Adviser: Hanadi S. Rifai.

Thesis (Ph.D.)--University of Houston, 2006.

Polychlorinated dibenzo-p-dioxins and dibenzofurans are two groups of chlorinated aromatic toxics that are highly persistent and widespread in the environment. These compounds have been the subject of much concern and debate due to their proven carcinogenic and bioaccumulative properties even at ultra-trace levels. In this research, ambient air concentrations and deposition rates of dioxins were monitored at a number of locations in the Houston area. Ambient concentrations were measured using high-volume air samplers while deposition rates were quantified using modified automated B1C samplers. Results indicated that all the 17 congeners are present in the ambient air of Houston. The most toxic congener, 2,3,7,8-TODD, was detected at concentrations between 0 and 2 fg/m3. While OCDD was the most prevalent congener in terms of dioxin mass in ambient air, 2,3,4,7,8-PeCDF was the main constituent of the total toxic concentration, I-TEQ. Statistical analysis confirmed temporal and spatial trends in the gathered ambient data. Higher ambient air concentrations were measured during the colder months. The collected data at the five monitoring sites also suggested a potential contribution from traffic. The particle size distribution data collected in this research showed that the dioxin congeners preferentially associated with particles with an aerodynamic diameter of <0.95 mum. The distribution between the vapor/particle phases in the atmosphere indicated a correlation with the level of chlorination and ambient temperature. Properties such as the subcooled liquid vapor pressure (PL°) and octanol-air partitioning coefficient (Koa) were used to describe the vapor-particle partitioning of the dioxins. Ambient air data were correlated to routinely measured air quality pollutants.

ISBN: 9780542781766Subjects--Topical Terms:

1019179
Atmospheric Sciences.

Atmospheric concentrations, deposition and modeling of polychlorinated dibenzo-p-dioxins and dibenzofurans.
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