Microelectrode measurement of ammonium profiles in freshwater sediments
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چکیده
منابع مشابه
Development of a Novel Nh4-selective Microelectrode Measurement of Ammonium in Haemolymph and Malpighian Tubule Secretion in Drosophila Melanogaster: Application of a Novel Ammonium-selective Microelectrode
The transport of ammonia by various tissues throughout the body is of fundamental importance for nitrogen excretion in invertebrates, yet sites and mechanisms of ammonia transport are not presently well understood. In this thesis a novel ammonium-selective microelectrode was developed using the crown ether ionophore TD19C6, which is approximately 3800-fold more selective for NH 4 + than Na + co...
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Sediments from the Belgian North Sea (BNS), the Western Scheldt Estuary (SE) and freshwater watercourses from the Scheldt basin were analysed for eight PBDE congeners, namely BDEs 28, 47, 99, 100, 153, 154, 183 and 209. Previously analysed biological samples from the same locations in the BNS and the SE have been shown to contain large amounts of PBDEs. Surprisingly, PBDE concentrations in the ...
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Ammonium production in the presence of specific inhibitors of sulfate reduction and methanogenesis was investigated in six marine sediments which differed in bulk properties and organic matter input. In all cases, little effect of the inhibitors on ammonium production was observed, although sulfate reduction was suppressed by molybdate. This gives evidence that the processes of fermentation and...
متن کاملAmmonium secretion by Malpighian tubules of Drosophila melanogaster: application of a novel ammonium-selective microelectrode.
Ammonia is a toxic nitrogenous waste product of amino acid metabolism that may accumulate to high levels in the medium ingested by larvae of the fruit fly Drosophila melanogaster. Here we report measurements of haemolymph NH4(+) concentration and the secretion of NH4(+) by the Malpighian (renal) tubules. Measurement of NH4(+) concentrations in secreted droplets is complicated either by the requ...
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ژورنال
عنوان ژورنال: FEMS Microbiology Ecology
سال: 1991
ISSN: 0168-6496
DOI: 10.1111/j.1574-6941.1991.tb01732.x