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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.

Heavy metal concentrations in plaice (Pleuronectes platessa L.) from the North Eastern Irish Sea and their possible effects on growth

Tizini, Omar Abdullah January 2003 (has links)
No description available.

Instrumentation and methodology for the monitoring of organic pollutants in water courses

Assim, Zaini Bin January 1990 (has links)
No description available.

Investigation of androgen receptor antagonist compounds present in influent and effluent from a wastewater works

Oladapo, Francis Olumide January 2012 (has links)
A wide range of synthetic chemicals and their metabolites present in the environment can antagonise the receptor activity of androgen hormones present in wildlife and humans. With increasing global production of new synthetic chemicals, little is known about their environmental fate, health consequences and end-points. This study was conducted to identify and characterise chemicals with anti-androgenic activity present in wastewater influent and effluent. This study was undertaken by applying a combination of biological and analytical chemistry techniques involving Solid Phase Extraction (SPE), High Performance Liquid Chromatography (HPLC) and an in vitro steroid receptor assay for profiling and characterising extracts of grab influent and effluent wastewater samples using a toxicity identification and evaluation (TIE) procedure. Initial work revealed variable recoveries of anti-androgenic activity from SPE of wastewaters. Therefore SPE methodology to screen wastewater samples was developed using a mixture of selected compounds which possess a range of polarities (log Kow). Their recoveries from SPE were measured by HPLC protocol and ranged from 95- 100%. The mean±SD and % RSD values of the analysed wastewater replicates were 3.20±0.03 mgFeq/L and 0.78% for influent and 0.22±0.01 mgFeq/L and 3.80% for effluent samples. The recoveries of wastewater extracts after fractionation were between 78.6% and 99.6%. Fractions containing anti-androgenic activity were analysed by Gas Chromatography Mass Spectrometry (GC-MS). A number of household chemicals were detected in both influent and effluent wastewater fractions that contained antiandrogenic activity. These included the anti-bacterial agents- triclosan, chlorophene, dichlorophene, chloroxylenol, the musk fragrance galaxolide, the flame retardantstris( 1-chloro-2-propyl)phosphate (TCPP) and tris(2-butoxyethyl)phosphate (TBEP), polymer plasticizer n-butylbenzenesulfonamide (NBBSA) and bisphenol A (BPA) which is a chemical associated with the polycarbonate usage. The anti-androgenic potency of pure contaminants compared with that of flutamide ranged from 0.04 (TCPP) to 13.40 (chlorophene). Anti-androgenic activity of 1.69 and 2.00% was recovered from the fractions of the effluent and influent samples respectively indicating that AA of about 98% are yet to be recovered. This work reveals for the first time that over 12 contaminants contribute to the total anti-androgenic activity present in wastewater effluent and that a number of compounds commonly used in household products (such as chlorophene, triclosan and NBBSA) are predominant anti-androgens in wastewater effluents.

A system model for stream pollution management

Norling, Richard Arthur, 1945- January 1970 (has links)
No description available.

Development and application of a rational water quality planning model

Dysart, Benjamin Clay 05 1900 (has links)
No description available.

Effects of city effluents on fish populations of Mill Creek, Fulton County, Indiana

Morgan, Frederic Lee January 1969 (has links)
There is no abstract available for this dissertation.

The use of krypton as a tracer to quantify reaeration in surface waters

Murphy, J. L. January 2003 (has links)
No description available.

Pesticides in the aquatic environment.

Hext, Herbert Daniel January 1973 (has links)
A comprehensive literature review is presented concerning pesticides; in particular the organochlorine insecticides, DDT and dieldrin, and their role in the pollution of water resources. The results of a laboratory study on the removal of DDT and dieldrin (HEOD) by adsorption onto a clay of the montmorillonite type (bentonite) are presented. For an initial DDT concentration of 100 μgm/l, the addition of bentonite at concentrations of 1.0 gm/l and 10.0 gm/l results in the removal of about 60 and 72 per cent, respectively, of the insecticide. For an initial HEOD concentration of 100 μgm/1, the addition of bentonite at concentrations of 1.0 gm/l and 10.0 gm/l brings about the removal of about 15 and 30 per cent, respectively, of this insecticide. The results of a laboratory study on the desorption of DDT and HEOD from the bentonite are presented. Both insecticides are desorbed from the clay, the HEOD being desorbed to the greater extent and the DDT desorption being quite minimal. The results of a further laboratory study conducted to ascertain the ability of bentonite clay to remove, by adsorption, insecticides from solution while settling through a quiescent water body are presented. Bentonite at concentrations of 1.0, 5.0, and 10.0 gm/l removes about 44, 48, and 54 per cent, respectively, of DDT from the quiescent water body initially containing 100 μgm/1 DDT. Bentonite at concentrations of 1.0, 5.0 and 10.0 gm/l removes about 14, 23, and 30 per cent, respectively, of the HEOD from the quiescent water body initially containing 100 μgm/1 HEOD. The results of an inorganic blanketing study indicates that the addition of a layer of sand over DDT and HEOD contaminated benthic deposits will block, somewhat, the desorption of these insecticides into the overlying waters. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

A survey of industrial water pollution in the pulp and paper industry of the United States.

Campbell, Stephen Wayne 01 January 1972 (has links) (PDF)
No description available.

Microcolony enumeration and immunofluorescent identification of group D streptococci occurring in sewage and polluted waters.

Beaudoin, Elizabeth Clausen 01 January 1979 (has links) (PDF)
No description available.

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