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Pavlotskaya, F.I.; Goryachenkova, T. A.; Kazinskaya, I. E.; Новиков, А. П.; Myasoedov, Β. F.; Kuznetsov, Yu.V.; Legin, V.K.; Shishkunova, L. V.

doi:10.1023/a:1026280430147

Cited by 20 publications

(9 citation statements)

References 6 publications

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“…The percentage of Pu in fraction 1 + 2 (19.4) in this sample taken from horizon 20 323 cm of the sediment is lower than that previously found in the bottom sediment collected from other areas of Pond V-10 (34 and 65; these samples were taken from horizons 0 33 and 12315 cm, respectively) [3]. Evidently, this is due to the fact that the Pu partitioning to humus acids bound to refractory sesquioxides and clay mineral (fraction 3) increases with depth (in the sample in hand, 31% of Pu was found in this fraction).…”

contrasting

confidence: 68%

“…It was demonstrated that the percentage of stable elements in the exchangeable fraction decreases in the order Ca (5.0) > Mn (2.2) > Fe (0.14). A different order was obtained for mobile and acid-soluble fractions: Mn (16.6 and 6.2%) > Fe (5.7 and 6.8%) > Ca (4.3 and 1.6%), Mg (1.6 and 3.6%) > Al (1.2 and 1.4%) [6]. The total percentage of Mn and Fe in mobile and acid-soluble fractions is 22.8 and 12.5, respectively.…”

mentioning

confidence: 93%

“…Similarly to Pu, the major parts of stable elements (75397%) were found in the mineral residue (poorly soluble fraction). In the bottom sediment collected from the submerged channel area of Pond V-10, the percentage of Fe in the mobile and acid-soluble forms was found to be 4 318, and that in the mineral residue, 79383 [7].…”

mentioning

confidence: 96%

“…Pavlotskaya et al [6,7] have studied the distribution of Pu and the most significant stable elements among geochemical phases of bottom sediments of the Yenisei River. It was demonstrated that the percentage of stable elements in the exchangeable fraction decreases in the order Ca (5.0) > Mn (2.2) > Fe (0.14).…”

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confidence: 99%

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Comparison of Methods for Assessing Plutonium Speciation in Environmental Objects

et al. 2005

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Several methods for Pu speciation study are compared using the same sample of bottom sediment. Data on Pu distribution among different soil fractions (water-soluble, exchangeable and readily soluble, mobile, associated with organic matter, including humic and fulvic acids, and also with amorphous hydroxides, primarily of iron and manganese) are reported. The major fraction of plutonium is associated with the organic matter. The experimental results on the Pu speciation, obtained by different methods, show satisfactory agreement.To predict of the radiation situation and develop measures aimed at rehabilitation of contaminated territories, knowledge is required not only of the contamination levels, but also of the radionuclide speciation in the biosphere, since the partitioning of radionuclides to components of environmental objects controls the direction and rate of their migration in the systems water3bottom sediment, soil3plant, and groundwater3rock.Study of the speciation of radionuclides and stable elements is a challenging problem. Soils and bottom sediments are multiphase systems in which diverse physicochemical, chemical, and biological processes occur. Furthermore, sequential extraction (SE) methods (successive leaching of a sediment using increasingly aggressive treatments) commonly used in such studies have such limitations as nonselectivity of the extractants for the individual target phases and incomplete extraction of these phases. The sediment phase dissolved by a given treatment is operationally defined. This phase is considered as a totality of chemically similar compounds. Generally the SE methods are based on different solubility of the target phases. Despite the indicated limitations, these methods are widely used in geochemistry, soil science, and radioecology, in studying the speciation of radionuclides and stable elements, and the results obtained provide valuable information on their environmental fate.In this study we compare several SE methods for Pu speciation, used in Russia and abroad, with the goal of their further improvement. As a subject matter we used bottom sediment collected from Pond V-10 (horizon 20 323 cm) at the Mayak Production Association. This pond was designed for storage of low-level liquid radioactive wastes and natural remediation through sorption of radionuclides on bottom sediments and also by radioactive decay of short-lived radionuclides. The sample used was a light loam, dun in color, peat-mineralized.The contents of stable elements in the sample were as follows: K 5.1, Na 5.6, Sr 0.2, Ca 23.0, Mg 8.2, Fe 20.0, Al 26.0, and Mn 0.8 mg per gram air-dry sample; C 14.4, H 2.4, and N 2.1%. The contents of radionuclides (Bq/g air-dry sample): 238!240 Pu 13.4 + 1.0 ( 238 Pu 6.1 + 0.7 and 239, 240 Pu 7.3 + 0.2), 60 Co 1.4 + 0.2, 90 Sr 185 + 6, 137 Cs 304 + 3, and 241 Am 2.0 + 0.2. In all cases, 1-g samples were taken for analysis.

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contrasting

confidence: 68%

mentioning

confidence: 93%

mentioning

confidence: 96%

mentioning

confidence: 99%

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Comparison of Methods for Assessing Plutonium Speciation in Environmental Objects

et al. 2005

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“…The experiments with soils of the forest and forest-steppe zones, contaminated with Pu under the laboratory conditions, revealed that plutonium is associated with all fractions of the organic matter of the soil. The Pu content in the HA fraction increases in the order soddy-podzolic (16%) < gray-forest (25%) < leached chernozem (40 371%) [2,3]. Plutonium from the global fallout in soils with high organic matter content (50%) is associated essentially with HA and FA fractions (about 60 and 537%, respectively) [4].…”

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confidence: 99%

Distribution of 137Cs, 90Sr, 239 + 240Pu, 241Am, and 244Cm among Components of Organic Matter of Soils in Near Exclusion Zone of the Chernobyl NPP

2005

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Distribution of Chernobyl-derived 137 Cs, 90 Sr, 239 + 240 Pu, 241 Am, and 244 Cm among organic fractions of soddy-podzolic, sandy, soddy-meadow, and peat soils collected from the Chernobyl Exclusion Zone along the North-Western radioactive fallout track was determined. Regardless of the soil type, 80 385% of 137 Cs is tightly fixed on the mineral fraction of the soil. Depending on the soil type, 50 370% of 90 Sr and 153 45% of 241 Am are associated with fulvic acid fractions. 241 Am and 244 Cu are similarly distributed among the organic acid fractions. In all the soil types studied, 239 + 240 Pu is associated essentially with humic acid fractions. Natural 230, 232 Th and technogenic 239 + 240 Pu are similarly distributed among the organic fractions.

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