Monitoring the behavior of radioactive contaminants associated with military applications,nuclear power facilities,and interim storage of radioactive waste materials is of significant concern in radiological analysis....Monitoring the behavior of radioactive contaminants associated with military applications,nuclear power facilities,and interim storage of radioactive waste materials is of significant concern in radiological analysis.Four sequential extraction schemes(SES) for fractionation of ^(241)Am were compared using five different types of soils,Vertisol,Cambisol,Chromic Luvisol,Eutric Fluvisol,and mixed urban soil,collected from different parts of Bulgaria.The results for the exchangeable ^(241) Am were in a wide range and depended on the SES used.Soil ^(241)Am varied from 0.5%to 6%in the exchangeable phase,from 0.5%to 35%in the carbonate phase,from0.4%to 36%in the reducible phase(easily reducible and moderately reducible),from 3%to 17%in the oxidizable phase,and from10%to 50%in the residual phase.After 100 d of contamination,around 50%of soil ^(241)Am was permanently fixed in the residual phase.There was strong evidence that the preferable soil phase for ^(241) Am was the carbonate phase.The transfer factor of ^(241) Am in the soil-plant system depended on ^(241)Am in the easily oxidizable phase(fulvic acid(FA)+humic acid(HA) phase).These confirmed the applicability of the National Institute of Standards and Technology(NIST) sequential extraction scheme for fractionation of soil^(241) Am since it includes extraction of FA+HA phase and then the carbonate phase.展开更多
文摘Monitoring the behavior of radioactive contaminants associated with military applications,nuclear power facilities,and interim storage of radioactive waste materials is of significant concern in radiological analysis.Four sequential extraction schemes(SES) for fractionation of ^(241)Am were compared using five different types of soils,Vertisol,Cambisol,Chromic Luvisol,Eutric Fluvisol,and mixed urban soil,collected from different parts of Bulgaria.The results for the exchangeable ^(241) Am were in a wide range and depended on the SES used.Soil ^(241)Am varied from 0.5%to 6%in the exchangeable phase,from 0.5%to 35%in the carbonate phase,from0.4%to 36%in the reducible phase(easily reducible and moderately reducible),from 3%to 17%in the oxidizable phase,and from10%to 50%in the residual phase.After 100 d of contamination,around 50%of soil ^(241)Am was permanently fixed in the residual phase.There was strong evidence that the preferable soil phase for ^(241) Am was the carbonate phase.The transfer factor of ^(241) Am in the soil-plant system depended on ^(241)Am in the easily oxidizable phase(fulvic acid(FA)+humic acid(HA) phase).These confirmed the applicability of the National Institute of Standards and Technology(NIST) sequential extraction scheme for fractionation of soil^(241) Am since it includes extraction of FA+HA phase and then the carbonate phase.
