タグ「137Cs」
Title: Radioecological evaluation of protective activities applied in agricultural sphere in Belarus between 2000 and 2005. (to the 20th anniversary of the Chernobyl disaster)
Author: Podolyak A.G., Bogdevich I.M., Ageets V.Yu., Timofeev S.F.
Reference: Radiation Biology, Radioecology, (Russian:“РАДИАЦИОННАЯ БИОЛОГИЯ. РАДИОЭКОЛОГИЯ “), Volume 47, Issue 3, 2007, Pages 356-370
ISSN: 0869-8031
DOI: 10.1134/S0869803107030162
Keywords: Belarus, protective activities in agriculture, 137Cs , 90Sr, 2000~2005
Abstract: Gives basic evaluation of protective activities, in agriculture, in the land contaminated by the Chernobyl accident. Analysis of the principles of the activities of 90sr and 137cs. Evaluation of liquidation of the disaster.
URL: http://elibrary.ru/item.asp?id=9516611
Title: Migration ability of radionuclides in soil-vegetation cover of Belarus after Chernobyl accident
Author: G.A. Sokolik, T.G. Ivanova, S.L. Leinova, S.V. Ovsiannikova, I.M. Kimlenko
Reference: Environment International, Volume 26, Issue 3, January 2001, Pages 183-187
DOI: http://dx.doi.org/10.1016/S0160-4120(00)00104-5
Keywords: Radionuclides; Cesium-137; Strontium-90; Plutonium-239, 240; Americium-241; “hot” particles; Physicochemical State; Chernobyl accident; Migration parameters; Biological accessibility
Abstract: This paper illustrates the experimental experience achieved in the research of the self-restoration of radioactive-contaminated natural ecosystems. The main directions of studies were: the content and geochemical stability of “hot” particles in radioactive fallout from Chernobyl accident; the physicochemical forms (water-soluble, exchangeable, mobile and fixed) of Cs-137, Sr-90, Pu-239, 240 and Am-241 in the wide varieties of soils; the biological accessibility of radionuclides and their contents in soil pore solutions; and the dynamics and migration parameters of radionuclides vertical redistribution in different landscape conditions.
URL: http://www.sciencedirect.com/science/article/pii/S0160412000001045
Title: Testing of a foodchain model using Chernobyl 137Cs fallout data and considering the effect of countermeasures
Author: Zitouni Ould-Dada
Reference: Science of The Total Environment, Volume 301, Issues 1–3, 1 January 2003, Pages 225-237
DOI: http://dx.doi.org/10.1016/S0048-9697(02)00285-1
Keywords: Chernobyl; 137Cs; Foodchain; Countermeasures; SPADE; Dose assessment; Uncertainty; BIOMASS
Abstract: Chernobyl 137Cs fallout data obtained during the period 1986–1996 from the most contaminated area in Russia were used within the IAEA BIOMASS programme to test the reliability of radiological assessment models. This model-testing scenario included information and data on countermeasures that were applied in the test area after the accident. This paper presents the predictions of the terrestrial foodchain model SPADE that was used in this model-testing exercise. SPADE predictions compared reasonably well with test data except for pigs and wild berries where differences were up to a factor of 50 and 200, respectively. Estimated intake of 137Cs and ingestion dose by adult men and women living in the test area compared favourably with the test data. Overall, SPADE proved to be capable of simulating agricultural countermeasures and their effectiveness. Modelling of countermeasures was found to be a complex process with large uncertainties regarding their ‘real’ implementation and effectiveness. The lessons learned from this exercise will be valuable in making future dose assessments/reconstructions involving countermeasures with improved results.
URL: http://www.sciencedirect.com/science/article/pii/S0048969702002851
Title: Determination of 99Tc deposited on the ground within the 30-km zone around the chernobyl reactor and estimation of 99Tc released into atmosphere by the accident
Author: S. Uchida, K. Tagami, W. Rühm, E. Wirth
Reference: Chemosphere, Volume 39, Issue 15, December 1999, Pages 2757-2766
DOI: http://dx.doi.org/10.1016/S0045-6535(99)00210-6
Keywords: Technetium-99; Chernobyl accident; Forest soil; Deposition; Cesium-137; Migration
Abstract: Technetium-99 was determined in samples from the 30-km zone around the Chernobyl reactor. Concentrations of 99Tc in soil samples taken from three forest sites ranged from 1.1 to 14.1 Bq kg−1 dry weight for the organic soil layers, and from 0.13 to 0.83 Bq kg−1 dry weight for the mineral soil layers. In particular, for the organic layers, the measured 99Tc concentrations were one or two orders of magnitude higher than those due to global fallout 99Tc. The 99Tc depositions (Bq m−2), based on the sum of the depositions measured in organic and mineral layers, ranged from 130 Bq m−2 within the 10-km zone to about 20 Bq m−2 close to the border of the 30-km zone. Taking the corresponding measured 137Cs depositions into account, it was found that the activity ratio of ranged from 6 × 10−5 to 1.2 × 10−4. It was estimated that about 970 GBq of 99Tc had been released by the Chernobyl accident. This figure corresponded to 2%–3% of the total 99Tc inventory in the core.
URL: http://www.sciencedirect.com/science/article/pii/S0045653599002106
Title: Atmospheric deposition of cosmogenic 7Be and 137Cs from fallout of the Chernobyl accident
Author: C. Papastefanou, A. Ioannidou, S. Stoulos, M. Manolopoulou
Reference: Science of The Total Environment, Volume 170, Issues 1–2, 18 August 1995, Pages 151-156
DOI: http://dx.doi.org/10.1016/0048-9697(95)04608-4
Keywords: Atmospheric depositional flux; Cosmogenic radionuclides; Chernobyl accident
Abstract: Atmospheric (tropospheric) depositional fluxes of the naturally occurring 7Be of cosmogenic origin and 137Cs from fallout of the Chernobyl accident were measured over a 7-year period (January 1987–December 1993) at Thessaloniki, Greece (40° 38′N, 22° 58′E). The annual total deposition fluxes of 7Be varied between 854 Bq/m2 (1987) and 1242 Bq/m2 (1992), showing a minimum in the years 1988–1989. The annual total deposition fluxes of 137Cs varied between 183 Bq/m2 (1987) and 16.4 Bq/m2 (1992), showing a significant decrease as expected for natural removal and radioactive decay and no new releases from nuclear facilities or weapons testing. The annual average total deposition velocity for 7Be was from 0.3 cm/s (1988) up to 0.8 cm/s (1991), while for 137Cs the corresponding values were much higher, hence 137Cs was associated with larger atmospheric particles. High 7Be concentrations in air were related to the very little solar activity (1987–1988 and 1993–1994), while low 7Be concentrations in air related to the high solar activity (1989–1991). Maximum 137Cs concentrations in air were registered during the spring 1991 and 1992, reflecting some stratospheric inputs. An unusual highly elevated value of 137Cs concentration in air, reaching 0.25 mBg/m3, was observed during the summer 1990.
URL: http://www.sciencedirect.com/science/article/pii/0048969795046084
Title: The transfer capability of long-lived Chernobyl radionuclides from surface soil to river water in dissolved forms
Author: H Amano, T Matsunaga, S Nagao, Y Hanzawa, M Watanabe, T Ueno, Y Onuma
Reference: Organic Geochemistry, Volume 30, Issue 6, June 1999, Pages 437-442
DOI:http://dx.doi.org/10.1016/S0146-6380(99)00028-5
Keywords: Sr-90; Cs-137; Transuranic elements; Speciation; Surface soil; Runoff; Dissolved organic materials; Fulvic acid; Ultrafiltration; Chernobyl 30 km zone
Abstract: Hydrologic runoff is one of the main processes in which radionuclides deposited in the surface environment migrate widely in both particulate and dissolved forms. This paper focuses on the transfer capability of long lived Chernobyl radionuclides from surface soil to river water in dissolved forms. First, concentration and speciation of radioactive Cs, Sr and transuranic isotopes, such as Pu and Am, were examined in undisturbed surface soil along the river in the exclusion zone (30 km zone) near the Chernobyl Nuclear Power Plant (NPP) in order to validate the radioactive contamination characteristics. Almost all radioactivities exist in the very top surface in the undisturbed soil layer. Sr-90 in the soil was estimated to be highest in the water soluble and exchangeable fractions, which were easily accessible to river water as a dissolved fraction. Pu isotopes and Am-241 are major radionuclides in free humic and free fulvic acid fractions. Secondly, surface soil near the Sahan River was extracted with distilled water, as an analogue of rain water, to estimate the dissolved fraction in runoff components from surface soil to river water. After a filtration procedure, extracted water was treated with ultra filtration techniques separating the molecular weight fractions of beyond and below 10,000 Da. Each fraction was measured for the radioactivity and the characteristics of organic materials including humic substances. Most Pu and Am exist in the molecular weight fractions beyond 10,000 Da, in spite of the fact that most of the dissolved organic fractions exist below 10,000 Da. This means that transuranic elements such as Pu and Am are associated with mobile high molecular weight materials like fulvic acids in water leachates.
URL: http://www.sciencedirect.com/science/article/pii/S0146638099000285
Title: Application of Chernobyl-derived for the assessment of soil redistribution within a cultivated field
Author: Valentin Golosov
Reference: Soil and Tillage Research, Volume 69, Issues 1–2, February 2003, Pages 85-98
DOI: http://dx.doi.org/10.1016/S0167-1987(02)00130-7
Keywords: Chernobyl; ; Soil redistribution; Erosion; Method
Abstract: Vast areas of Europe were contaminated by the Chernobyl-derived in April–May 1986. This paper reports a detailed study of the post-fallout redistribution within a 1 ha field located in the Chasovenkov Verh catchment in the northern part of the Middle-Russian upland. Particular attention was paid to the study of reference inventories. It is shown that the random spatial variability of is similar within undisturbed and cultivated parts of a flat interfluve. Systematic spatial variability is not essential for a relatively short (200 m) topographical unit with simple relief. The analysis of a soil redistribution pattern within the study field using the Chernobyl technique demonstrates that it is possible to identify areas of soil loss/gain. This pattern does not reflect soil redistribution for the whole field, because these have been only 12 years since the Chernobyl accident. Net erosion rates based on method were comparable to soil losses directly measured at the study field.
URL: http://www.sciencedirect.com/science/article/pii/S0167198702001307
Title: Nuclear weapon and Chernobyl debris in the troposphere and lower stratosphere
Author: Ludwika Kownacka, Zbigniew Jaworowski
Reference: Science of The Total Environment, Volume 144, Issues 1–3, 29 April 1994, Pages 201-215
DOI: http://dx.doi.org/10.1016/0048-9697(94)90439-1
Keywords: Radionuclides; Troposphere; Stratosphere; Nuclear tests; Chernobyl
Abstract: High altitude aircraft sampling of aerosols has been carried out at 4–7 levels up to 15 km over Poland. From 1973 to 1991 a total of 102 vertical concentration profiles of 90Sr, 134Cs and 137Cs, and 83 profiles of 144Ce were determined. One year after the sub-megaton nuclear test in 1980, 137Cs was almost completely removed from the stratosphere. The Chernobyl debris was found in the stratosphere from the third day after the accident until the end of 1991. In May 1986 the concentration of 134Cs and 137Cs at stratospheric altitudes reached about 0.5% of that between the ground level and 3 km. Residence times of Chernobyl radiocesium in the lower stratosphere systematically increased between 1987 and 1991, in variance with those of the debris from nuclear tests. The vertical concentration profiles and the long residence times of radiocesium indicate that the non-violent meteorological processes were transporting the Chernobyl debris into the lower stratosphere, immediately and long after the accident. We postulate that the same quiescent processes transport vast amounts of resuspended particulate organics from the surface of land and sea into high altitudes, and may thus bear on the chemistry of the stratosphere.
URL: http://www.sciencedirect.com/science/article/pii/0048969794904391
Title: Radioactivity measurements in air over Europe after the Chernobyl accident
Author: Frank Raes, Giovanni Graziani, David Stanners, Franco Girardi
Reference: Atmospheric Environment. Part A. General Topics, Volume 24, Issue 4, 1990, Pages 909-916
DOI: http://dx.doi.org/10.1016/0960-1686(90)90293-V
Keywords: Chernobyl; air concentrations; LRT; Cs-134/Cs-137
Abstract: A comprehensive European data set of radioactivity in air caused by the accident at the Chernobyl nuclear power plant is presented. For the first 2 weeks after the beginning of the release, levels of particulate I-131, Cs-134 and Cs-137 (85 locations) and of total I-131 (10 locations) are given. All data are stored in a computerized data base. For the first time the passage of the Chernobyl cloud over Europe is mapped after re-averaging the time histories in each location to produce coherent daily concentrations. Cs-134/Cs-137 ratios were analyzed: the ‘European’ average ratio calculated from 1239 samples is 0.55, with a standard deviation of 0.25.
URL: http://www.sciencedirect.com/science/article/pii/096016869090293V
Title: Countermeasures in agricultural production as an effective means of mitigating the radiological consequences of the Chernobyl accident
Author: R.M. Alexakhin
Reference: Science of The Total Environment, Volume 137, Issues 1–3, 2–4 September 1993, Pages 9-20
DOI:http://dx.doi.org/10.1016/0048-9697(93)90374-F
Keywords: Chernobyl accident; agriculture; caesium-137; radioactive contamination; countermeasures
Abstract: In the wake of the Chernobyl accident of 1986, the implementation of a variety of protective measures in agriculture has been the most effective means of reducing the total radiation dose of the population; reduction of external radiation by soil decontamination is much less cost effective. As a result of the agricultural countermeasures, internal doses have been decreased by a factor of approximately three. In Russia, these countermeasures resulted in a decrease of 137Cs accumulation in arable crops by a factor of about 2.3 and in pastures of about 2.8. Reduction of radiocaesium in herbage is one of the most importance factors, since this results in a reduction of 137Cs in milk — the main source of radiation dose in the human diet. Countermeasures used on grazing land included ploughing, liming, application of fertilisers etc. 137Cs in plant crops can be decreased 5–10 times by changing the type of crops cultivated. In natural meadows and pastures and on arable soils without the benefit of treatment, it has been observed that plant uptake of 137Cs decreased with time. The efficiency of different protective measures in agriculture has been assessed in the accident-affected zone.
URL: http://www.sciencedirect.com/science/article/pii/004896979390374F
