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Studies of actinides in a superanoxic fjord

Roos, Per LU (1997)
Abstract (Swedish)
Popular Abstract in Swedish

Actinidelementen plutonium, americium, torium och uran har analyserats i sediment och vatten i den superanoxiska Framvaren fjord, Norge. Koncentrationerna av Pu och Am i fjordens bottenvatten hör till de högst uppmätta i den marina miljön och toriumkoncentrationerna är de högsta uppmätta i någon marin miljö. Ultrafiltrering av fjordvattnet visar att en stor andel (40-60%) av dessa aktinider är associerade till kolloidalt material (10kD-0.2 um). Detta gäller även för uran. Orsaken till de höga aktinidkoncentrationerna är mobilisering av aktinider från sedimenten. Djupprofilen i vattenpelaren av aktiniderna (associerade till kolloidalt material)har samma utseende som många andra substanser som... (More)
Popular Abstract in Swedish

Actinidelementen plutonium, americium, torium och uran har analyserats i sediment och vatten i den superanoxiska Framvaren fjord, Norge. Koncentrationerna av Pu och Am i fjordens bottenvatten hör till de högst uppmätta i den marina miljön och toriumkoncentrationerna är de högsta uppmätta i någon marin miljö. Ultrafiltrering av fjordvattnet visar att en stor andel (40-60%) av dessa aktinider är associerade till kolloidalt material (10kD-0.2 um). Detta gäller även för uran. Orsaken till de höga aktinidkoncentrationerna är mobilisering av aktinider från sedimenten. Djupprofilen i vattenpelaren av aktiniderna (associerade till kolloidalt material)har samma utseende som många andra substanser som diffunderar från sedimenten. (Less)
Abstract
Water column and sediment profiles of plutonium, americium, thorium and uranium have been obtained in the superanoxic Framvaren fjord, southern Norway. The concentrations of bomb test fallout Pu, Am as well as 'dissolved' Th in the bottom water are the highest recorded in the marine environment. The behaviour of the actinides in the anoxic water mass is to a large extent governed by the behaviour of the colloidal material, probably consisting of humic substances. Ultrafiltration reveals that 40-60% of the actinides are associated to the large colloids (10kD-0.2um), surprisingly this is valid also for uranium. Determination of oxidation state by chemical methods show that plutonium exist almost entirely as a trivalent species, while uranium... (More)
Water column and sediment profiles of plutonium, americium, thorium and uranium have been obtained in the superanoxic Framvaren fjord, southern Norway. The concentrations of bomb test fallout Pu, Am as well as 'dissolved' Th in the bottom water are the highest recorded in the marine environment. The behaviour of the actinides in the anoxic water mass is to a large extent governed by the behaviour of the colloidal material, probably consisting of humic substances. Ultrafiltration reveals that 40-60% of the actinides are associated to the large colloids (10kD-0.2um), surprisingly this is valid also for uranium. Determination of oxidation state by chemical methods show that plutonium exist almost entirely as a trivalent species, while uranium to at least 40% exist as U(IV). The uranium in the 10 kD permeate fraction was to a somewhat lesser extent in the reduced state indicating uranium to be stabilised in the reduced valence state by complex formation with humic colloids. The sediments acts as a source for Pu, A (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Dr Mitchell, Peter Ian, University College Dublin, Ireland
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Geology, colloids., TIMS, pore water, remobilisation, sediments, ultrafiltration, uranium, thorium, americium, plutonium, Anoxic, Framvaren, fjord, physical geography, Geologi, fysisk geografi
pages
66 pages
publisher
Radiation Physics, Lund
defense location
Department of Oncology, Lund University Hospital
defense date
1997-04-04 10:15
external identifiers
  • Other:ISRN: LUNFD6/(NFRA-1033)/1-66/1997, LUMEDW/(MERI-1033)/1-66/1997
ISBN
91-628-2438-4
language
English
LU publication?
yes
id
adf6d407-6ee8-4b3f-90ed-6c8790f22234 (old id 29086)
date added to LUP
2007-06-12 14:15:28
date last changed
2016-09-19 08:45:06
@misc{adf6d407-6ee8-4b3f-90ed-6c8790f22234,
  abstract     = {Water column and sediment profiles of plutonium, americium, thorium and uranium have been obtained in the superanoxic Framvaren fjord, southern Norway. The concentrations of bomb test fallout Pu, Am as well as 'dissolved' Th in the bottom water are the highest recorded in the marine environment. The behaviour of the actinides in the anoxic water mass is to a large extent governed by the behaviour of the colloidal material, probably consisting of humic substances. Ultrafiltration reveals that 40-60% of the actinides are associated to the large colloids (10kD-0.2um), surprisingly this is valid also for uranium. Determination of oxidation state by chemical methods show that plutonium exist almost entirely as a trivalent species, while uranium to at least 40% exist as U(IV). The uranium in the 10 kD permeate fraction was to a somewhat lesser extent in the reduced state indicating uranium to be stabilised in the reduced valence state by complex formation with humic colloids. The sediments acts as a source for Pu, A},
  author       = {Roos, Per},
  isbn         = {91-628-2438-4},
  keyword      = {Geology,colloids.,TIMS,pore water,remobilisation,sediments,ultrafiltration,uranium,thorium,americium,plutonium,Anoxic,Framvaren,fjord,physical geography,Geologi,fysisk geografi},
  language     = {eng},
  pages        = {66},
  publisher    = {ARRAY(0xb4adaf8)},
  title        = {Studies of actinides in a superanoxic fjord},
  year         = {1997},
}