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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
1990-1-18
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pubmed:abstractText |
Fixation of 137Cs was determined in lake sediment suspensions under controlled redox potentials in the laboratory. The activity of previously added 137Cs on various clay sites was determined by time-series selective extractions. Monovalent cations, particularly NH+4, were much more effective at displacing 137Cs than divalent cations or Na+. Ammonium ion (NH+4) and Na+ were used to extract 137Cs from selective and non-selective 137Cs-binding sites, respectively. The activity of water-soluble 137Cs and Na-extractable 137Cs was significantly higher under anaerobic redox conditions (-200 mV), when soluble NH+4 concentrations in the anaerobic suspensions were 1000 microM or higher. Activities of 137Cs were highest (initially 40-50% of the 137Cs added) on the NH+4-extractable site. Over the long term, activities of NH+4-extractable 137Cs decreased linearly to below 10% as 137Cs was fixed on inter-lattice sites. Water-soluble 137Cs was significantly correlated with Na-extractable 137Cs in short-term experiments, suggesting the existence of an equilibrium between the different clay sites. High concentrations of NH+4 under anaerobic redox conditions could shift this equilibrium, resulting in increases in water-soluble 137Cs and increases in the activities of 137Cs bound on non-selective clay sites. Additional studies are necessary to evaluate the interaction of 137Cs with sulfides, iron oxides, and other reactive chemical species which may attenuate 137Cs in sediment.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Cesium Radioisotopes,
http://linkedlifedata.com/resource/pubmed/chemical/Soil Pollutants,
http://linkedlifedata.com/resource/pubmed/chemical/Soil Pollutants, Radioactive,
http://linkedlifedata.com/resource/pubmed/chemical/Water Pollutants,
http://linkedlifedata.com/resource/pubmed/chemical/Water Pollutants, Radioactive
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pubmed:status |
MEDLINE
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pubmed:month |
Nov
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pubmed:issn |
0017-9078
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
57
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
781-9
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pubmed:dateRevised |
2001-3-23
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pubmed:meshHeading |
pubmed-meshheading:2592212-Cesium Radioisotopes,
pubmed-meshheading:2592212-Hydrogen-Ion Concentration,
pubmed-meshheading:2592212-Oxidation-Reduction,
pubmed-meshheading:2592212-Soil Pollutants,
pubmed-meshheading:2592212-Soil Pollutants, Radioactive,
pubmed-meshheading:2592212-Water Pollutants,
pubmed-meshheading:2592212-Water Pollutants, Radioactive
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pubmed:year |
1989
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pubmed:articleTitle |
Effect of redox potential on fixation of 137Cs in lake sediment.
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pubmed:affiliation |
Laboratory for Wetland Soils and Sediments, Louisiana State University, Baton Rouge 70803-7511.
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pubmed:publicationType |
Journal Article
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