51
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Todorović N, Stojković I, Nikolov J, Tenjović B. 90Sr determination in water samples using Čerenkov radiation. J Environ Radioact 2017; 169-170:197-202. [PMID: 28135650 DOI: 10.1016/j.jenvrad.2017.01.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 01/20/2017] [Accepted: 01/20/2017] [Indexed: 06/06/2023]
Abstract
A procedure for the determination of 90Sr in environmental water samples using Čerenkov radiation and low-level liquid scintillation counter Quantulus 1220 was applied and optimized. Low diffusion polyethylene vials, high performance glass counting vials and low potassium borosilicate glass vilas of 20 ml volume (all from PerkinElmer) were used in order to examine their potential effect on counting process. The derived efficiencies were 45.86(9)%, and a minimum detectable activity of 0.32 Bq l-1 in a 20 ml polyethylene vial (20 ml water sample) has been achieved during 300 min of measurement. Environmental water samples might be colored and this will lead to color quenching, which one of the most important problems that affect Čerenkov is counting (Mosqueda et al., 2005). The sample channel ratio (SCR) method has been applied to correct this effect. The analytical procedures and measurement techniques were tested by participating in the IAEA-TEL-2015-03 world-wide proficiency test on determination of 90Sr in water sample.
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Affiliation(s)
- Nataša Todorović
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia.
| | - Ivana Stojković
- University of Novi Sad, Faculty of Technical Sciences, Novi Sad, Serbia
| | - Jovana Nikolov
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Branislava Tenjović
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
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52
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Kocadag M, Exler V, Christopher BS, Baumgartner A, Stietka M, Landstetter C, Korner M, Maringer FJ. Environmental radioactivity study of Austrian and Bavarian forest ecosystems: Long-term behaviour of contamination of soil, vegetation and wild boar and its radioecological coherences. Appl Radiat Isot 2017; 126:106-111. [PMID: 28336263 DOI: 10.1016/j.apradiso.2017.03.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 03/06/2017] [Accepted: 03/10/2017] [Indexed: 11/28/2022]
Abstract
137Cs and 40K in soil, vegetation and flesh of wild boar samples from Austrian and Bavarian regions were investigated by gamma-ray spectrometry and 90Sr in bones of wild boar with Liquid Scintillation Counting (LSC) after radiochemical separation. The soil core profiles revealed that 70-97% of the soil caesium content is still accumulated in the 0-10cm soil depth. From all vegetation samples the mushrooms, particularly the bay boletus showed the highest 137Cs contamination. The activity concentration of 137Cs in muscle tissue of boar ranged from 14.9±1.5Bq/kg (Bavaria) to 4711±377Bq/kg (Lower Austria). In the bones of wild boars, 90Sr activity concentration ranged from 1.4±0.2Bq/kg (Bavaria) to 70.3±10.5Bq/kg (Upper Austria).
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Affiliation(s)
| | | | | | | | - Michael Stietka
- University of Natural Resources and Life Sciences, Vienna, Austria
| | | | - Martin Korner
- Austrian Agency for Health and Food Safety (AGES), Austria
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53
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Erchinger JL, Orrell JL, Aalseth CE, Bernacki BE, Douglas M, Fuller ES, Keillor ME, Marianno CM, Morley SM, Mullen CA, Panisko ME, Warren GA. Background characterization of an ultra-low background liquid scintillation counter. Appl Radiat Isot 2017; 126:168-70. [PMID: 28236554 DOI: 10.1016/j.apradiso.2017.01.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 01/06/2017] [Accepted: 01/25/2017] [Indexed: 11/21/2022]
Abstract
The Ultra-Low Background Liquid Scintillation Counter developed by Pacific Northwest National Laboratory will expand the application of liquid scintillation counting by enabling lower detection limits and smaller sample volumes. By reducing the overall count rate of the background environment approximately 2 orders of magnitude below that of commercially available systems, backgrounds on the order of tens of counts per day over an energy range of ~3-3600keV can be realized. Initial test results of the ULB LSC show promising results for ultra-low background detection with liquid scintillation counting.
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54
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Kelleher K, Wong J, León-Vintró L, Currivan L. International Rn-222 in drinking water interlaboratory comparison. Appl Radiat Isot 2017; 126:270-272. [PMID: 28187931 DOI: 10.1016/j.apradiso.2017.01.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 11/23/2016] [Accepted: 01/26/2017] [Indexed: 10/20/2022]
Abstract
A radon in drinking water interlaboratory comparison (ILC) was conducted between eight laboratories in Europe. The majority of the measurement results submitted were in agreement with the assigned value, with a single result deemed questionable. The questionable result does not deviate significantly from the assigned value but the measurement uncertainties associated with this result could be too small. The results from this ILC indicate that there is good agreement between participating laboratories for radon in water measurements.
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Affiliation(s)
- Kevin Kelleher
- Office of Radiological Protection, Environmental Protection Agency, 3 Clonskeagh Square, Clonskeagh Road, Dublin 14, Ireland.
| | - Jennie Wong
- Office of Radiological Protection, Environmental Protection Agency, 3 Clonskeagh Square, Clonskeagh Road, Dublin 14, Ireland
| | | | - Lorraine Currivan
- Office of Radiological Protection, Environmental Protection Agency, 3 Clonskeagh Square, Clonskeagh Road, Dublin 14, Ireland
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55
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Huxtable D, Read D, Shaw G. Measuring radon-222 in soil gas with high spatial and temporal resolution. J Environ Radioact 2017; 167:36-42. [PMID: 27843065 DOI: 10.1016/j.jenvrad.2016.11.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 10/24/2016] [Accepted: 11/01/2016] [Indexed: 06/06/2023]
Abstract
In order to exploit 222Rn as a naturally-occurring tracer in soils we need to sample and measure radon isotopes in soil gas with high spatial and temporal resolution, without disturbing in situ activity concentrations and fluxes. Minimisation of sample volume is key to improving the resolution with which soil gas can be sampled; an analytical method is then needed which can measure radon with appropriate detection limits and precision for soil gas tracer studies. We have designed a soil gas probe with minimal internal dead volume to allow us to sample soil gas volumes of 45 cm3. Radon-222 is extracted from these samples into a mineral oil-based scintillation cocktail before counting on a conventional liquid scintillation counter. A detection limit of 320 Bq m-3 (in soil gas) is achievable with a 1 h count. This could be further reduced but, in practice, is sufficient for our purpose since 222Rn in soil gas typically ranges from 2000-50,000 Bq m-3. The method is simple and provides several advantages over commonly used field-portable instruments, including smaller sample volumes, speed of deployment and reliability under field conditions. The major limitation is the need to count samples in a liquid scintillation counter within 2-3 days of collection, due to the short (3.824 day) radioactive half-life of 222Rn. The method is not applicable to the very short-lived (55 s half-life) 220Rn.
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Affiliation(s)
- Darren Huxtable
- University of Nottingham, School of Biosciences, Sutton Bonington Campus, Leicestershire, LE12 5RD, UK
| | - David Read
- Loughborough University, Department of Chemistry, Ashby Road, Loughborough, Leicestershire, LE11 3TU, UK
| | - George Shaw
- University of Nottingham, School of Biosciences, Sutton Bonington Campus, Leicestershire, LE12 5RD, UK
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56
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Villa-Alfageme M, Mas JL, Hurtado-Bermudez S, Masqué P. Rapid determination of (210)Pb and (210)Po in water and application to marine samples. Talanta 2016; 160:28-35. [PMID: 27591584 DOI: 10.1016/j.talanta.2016.06.051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 06/16/2016] [Accepted: 06/24/2016] [Indexed: 11/20/2022]
Abstract
Measurement of radionuclides in marine samples, specifically radioactive pairs disequilibrium, has gained interest lately due to their ability to trace cutting edge biogeochemical processes. In this context, we developed a fast, direct method for determining (210)Pb and (210)Po water through the use of ultra low-level liquid scintillation counting and alpha-particle spectrometry respectively and through Eichrom Sr resins for the Po-Pb separation. For (210)Pb analysis, the method uses stable lead as a yield tracer measured by a robust ICP-MS technique, and (210)Po is determined through self-deposition using the conventional (209)Po yield tracer. The improvements of the method over other techniques are: a) the analysis can be completed within 6 days, simplifying other methods, b) very low limits of detection have been achieved -0.12 and 0.005mBqL(-1) for (210)Pb and (210)Po, respectively - and c) most of the method could be carried out in on-board analysis. We applied the method to different aqueous samples and specifically to marine samples. We determined (210)Pb and (210)Po in the dissolved fraction of Mediterranean Sea water and an estuary at the South-West of Spain. We found that it can be successfully employed to marine samples but we recommend to i) use a minimum of 20L water to measure the (210)Pb in the dissolved phase by LSC and lower volumes to measure total concentrations; ii) wait for (210)Pb and (210)Bi in secular equilibrium and measure the total spectrum to minimise the limit of detection and improve accuracy.
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57
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Vagner I, Varlam C, Faurescu I, Faurescu D, Bogdan D, Bucura F. Method for organically bound tritium analysis from sediment using a combustion bomb. Appl Radiat Isot 2016; 118:136-9. [PMID: 27640174 DOI: 10.1016/j.apradiso.2016.09.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 08/23/2016] [Accepted: 09/08/2016] [Indexed: 11/22/2022]
Abstract
The method consisted in combustion, using a Parr bomb type 1121, of a sediment - tritium free promoter mixture. The proper ratio sediment to promoter in our experiments was between 1:3 and 1:2, higher ratio resulting in unreliable results, due to incomplete combustion of the sample. The described method was used to measure the estuarine sediment sample from the 2nd International OBT Intercomparison Exercise, the average reported value being 163±12Bqkg-1 dry matter (k=2).
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58
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Godoy JM, Vianna LM, Godoy MLDP, Almeida AC. Determination of (226)Ra in produced water by liquid scintillation counting. J Environ Radioact 2016; 160:25-27. [PMID: 27116402 DOI: 10.1016/j.jenvrad.2016.02.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/04/2016] [Accepted: 02/19/2016] [Indexed: 06/05/2023]
Abstract
It is proposed a method for the determination of (226)Ra in offshore platform liquid effluent samples (produced water). The method is based on a two-phase liquid scintillation counting system and allows for the direct and simple determination of (226)Ra content. Samples with high barium content may also have high (226)Ra concentration. Therefore, the sample volume is based on the barium concentration and ranges from 10 mL to 100 mL. Our new method was tested using multiple real samples and was compared with the BaSO4 precipitation method. The results based on the LSC were 30% higher than the precipitation method, which is attributed to the self-absorption of alpha particles in the BaSO4 precipitate. The determination of both (226)Ra and (228)Ra in the liquid effluent of offshore oil platforms is mandatory in Brazil. Thus, a second method of accurately assessing (228)Ra content remains necessary.
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Affiliation(s)
- José Marcus Godoy
- Department of Chemistry, Pontifícia Universidade Católica do Rio de Janeiro, Rua Marquês de São Vicente, 225 - Gávea, 22451-900 Rio de Janeiro, Brazil.
| | - Lucas M Vianna
- Department of Chemistry, Pontifícia Universidade Católica do Rio de Janeiro, Rua Marquês de São Vicente, 225 - Gávea, 22451-900 Rio de Janeiro, Brazil
| | - Maria Luiza D P Godoy
- Instituto de Radioproteção e Dosimetria, Avenida Salvador Allende s/n, Jacarepaguá, 22780-160 Rio de Janeiro, Brazil
| | - Ana Cristina Almeida
- Department of Chemistry, Pontifícia Universidade Católica do Rio de Janeiro, Rua Marquês de São Vicente, 225 - Gávea, 22451-900 Rio de Janeiro, Brazil
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59
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Stojković I, Todorović N, Nikolov J, Tenjović B. PSA discriminator influence on (222)Rn efficiency detection in waters by liquid scintillation counting. Appl Radiat Isot 2016; 112:80-8. [PMID: 27016710 DOI: 10.1016/j.apradiso.2016.03.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 02/18/2016] [Accepted: 03/17/2016] [Indexed: 11/15/2022]
Abstract
A procedure for the (222)Rn determination in aqueous samples using liquid scintillation counting (LSC) was evaluated and optimized. Measurements were performed by ultra-low background spectrometer Quantulus 1220™ equipped with PSA (Pulse Shape Analysis) circuit which discriminates alpha/beta spectra. Since calibration procedure is carried out with (226)Ra standard, which has both alpha and beta progenies, it is clear that PSA discriminator has vital importance in order to provide precise spectra separation. Improvement of calibration procedure was done through investigation of PSA discriminator level and, consequentially, the activity of (226)Ra calibration standard influence on (222)Rn efficiency detection. Quench effects on generated spectra i.e. determination of radon efficiency detection were also investigated with quench calibration curve obtained. Radon determination in waters based on modified procedure according to the activity of (226)Ra standard used, dependent on PSA setup, was evaluated with prepared (226)Ra solution samples and drinking water samples with assessment of measurement uncertainty variation included.
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Affiliation(s)
- Ivana Stojković
- University of Novi Sad, Faculty of Technical Sciences, Novi Sad, Serbia
| | - Nataša Todorović
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Jovana Nikolov
- University of Novi Sad, Faculty of Sciences, Department of Physics, Novi Sad, Serbia
| | - Branislava Tenjović
- University of Novi Sad, Faculty of Sciences, Department of Chemistry, Novi Sad, Serbia
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60
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Antohe A, Sahagia M, Luca A, Ioan MR, Ivan C. Measurement of liquid scintillation sources of (210)Pb obtained from (222)Rn decay. Appl Radiat Isot 2016; 109:286-9. [PMID: 26725538 DOI: 10.1016/j.apradiso.2015.12.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 12/03/2015] [Indexed: 11/21/2022]
Abstract
Liquid scintillation samples were filled with (222)Rn and the activity was measured with good precision after reaching the secular equilibrium with the progeny (218)Po, (214)Pb, (214)Bi and (214)Po. After decay of most of (222)Rn activity, the samples contain (210)Pb and progeny. The activities of (210)Pb and progeny can be calculated as a function of time using the initial (222)Rn activity. The samples were measured in a TDCR counter and the experimentally determined counting efficiencies are in accordance with previously published results.
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61
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Rodrigues M, Cassette P, Lépy MC, Loidl M, Ménesguen Y. Determination of absolute photon emission intensities of (210)Pb. Appl Radiat Isot 2016; 109:500-506. [PMID: 26774394 DOI: 10.1016/j.apradiso.2015.11.090] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 11/25/2015] [Indexed: 11/15/2022]
Abstract
Photon emission intensities of (210)Pb have been determined using sources prepared from a standard solution, whose activity was measured by liquid scintillation counting. The absolute γ-ray and X-ray emission intensity was measured by conventional γ-ray spectrometry. Complementary measurements of the L X-ray spectrum were performed using a cryogenic detector, characterized by very high energy resolution and constant detection efficiency. As a result, precise emission intensities of the individual X-ray lines were obtained taking into account the presence of satellite lines.
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Affiliation(s)
- Matias Rodrigues
- CEA, LIST, Laboratoire National Henri Becquerel, 91191 Gif-sur-Yvette Cedex, France.
| | - Philippe Cassette
- CEA, LIST, Laboratoire National Henri Becquerel, 91191 Gif-sur-Yvette Cedex, France
| | - Marie-Christine Lépy
- CEA, LIST, Laboratoire National Henri Becquerel, 91191 Gif-sur-Yvette Cedex, France
| | - Martin Loidl
- CEA, LIST, Laboratoire National Henri Becquerel, 91191 Gif-sur-Yvette Cedex, France
| | - Yves Ménesguen
- CEA, LIST, Laboratoire National Henri Becquerel, 91191 Gif-sur-Yvette Cedex, France
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62
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Jiang J, Davies A, Arrigo L, Friese J, Seiner BN, Greenwood L, Finch Z. Analysis of 161Tb by radiochemical separation and liquid scintillation counting. Appl Radiat Isot 2015; 170:107298. [PMID: 26699677 DOI: 10.1016/j.apradiso.2015.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 12/03/2015] [Indexed: 11/30/2022]
Abstract
The determination of 161Tb activity is problematic due to its very low fission yield, short half-life, and the complication of its gamma spectrum. At AWE, radiochemically purified 161Tb solution was measured on a PerkinElmer 1220 QuantulusTM Liquid Scintillation Spectrometer. Since there was no 161Tb certified standard solution available commercially, the counting efficiency was determined by the CIEMAT/NIST Efficiency Tracing method. The method was validated during a recent inter-laboratory comparison exercise involving the analysis of a uranium sample irradiated with thermal neutrons. The measured 161Tb result was in excellent agreement with the result using gamma spectrometry and the result obtained by Pacific Northwest National Laboratory.
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Affiliation(s)
- J Jiang
- AWE plc, Aldermaston, Reading RG7 4PR, UK.
| | - A Davies
- AWE plc, Aldermaston, Reading RG7 4PR, UK
| | - L Arrigo
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA
| | - J Friese
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA
| | - B N Seiner
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA
| | - L Greenwood
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA
| | - Z Finch
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MSIN J4-65, Richland, WA 99352, USA
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63
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Ziemek T, Jęczmieniowski A, Cacko D, Broda R, Lech E. A new 4π(LS)-γ coincidence counter at NCBJ RC POLATOM with TDCR detector in the beta channel. Appl Radiat Isot 2016; 109:290-5. [PMID: 26701653 DOI: 10.1016/j.apradiso.2015.12.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 12/04/2015] [Indexed: 11/20/2022]
Abstract
A new 4π(LS)-γ coincidence system (TDCRG) was built at the NCBJ RC POLATOM. The counter consists of a TDCR detector in the beta channel and scintillation detector with NaI(Tl) crystal in the gamma channel. The system is equipped with a digital board with FPGA, which records and analyses coincidences in the TDCR detector and coincidences between the beta and gamma channels. The characteristics of the system and a scheme of the FPGA implementation with behavioral simulation are given. The TDCRG counter was validated by activity measurements on (14)C and (60)Co solutions standardized in RC POLATOM using previously validated methods.
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64
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Altzitzoglou T, Bohnstedt A. Characterisation of the IAEA-375 Soil Reference Material for radioactivity. Appl Radiat Isot 2015; 109:118-121. [PMID: 26651166 DOI: 10.1016/j.apradiso.2015.11.053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 11/20/2015] [Indexed: 12/01/2022]
Abstract
The Joint Research Centre Institute for Reference Materials and Measurements (JRC-IRMM) participated in a research project initiated by the International Atomic Energy Agency (IAEA) to upgrade some of its existing reference materials (RMs). The aim of the work described in this article was to determine the activity concentration of a series of radionuclides in the IAEA-375 soil RM with values traceable to the SI units. The radionuclides (40)K, (134)Cs, (137)Cs, (212)Pb, (212)Bi, (214)Pb and (214)Bi were measured by γ-ray spectrometry after drying the sample and placing it in a suitable container. The (90)Sr was assessed by liquid scintillation counting after dissolution of the soil by wet digestion and chemical separation of Sr by extraction chromatography. This soil RM was used later as basis for the 2010 EC Interlaboratory Comparison on Radionuclides in Soil.
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Affiliation(s)
- T Altzitzoglou
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium.
| | - A Bohnstedt
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium
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65
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Erchinger JL, Aalseth CE, Bernacki BE, Douglas M, Fuller ES, Keillor ME, Morley SM, Mullen CA, Orrell JL, Panisko ME, Warren GA, Williams RO, Wright ME. Development of a low background liquid scintillation counter for a shallow underground laboratory. Appl Radiat Isot 2015; 105:209-18. [PMID: 26334781 DOI: 10.1016/j.apradiso.2015.08.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 08/05/2015] [Accepted: 08/18/2015] [Indexed: 11/22/2022]
Abstract
Pacific Northwest National Laboratory has recently opened a shallow underground laboratory intended for measurement of low-concentration levels of radioactive isotopes in samples collected from the environment. The development of a low-background liquid scintillation counter is currently underway to further augment the measurement capabilities within this underground laboratory. Liquid scintillation counting is especially useful for measuring charged particle (e.g., β and α) emitting isotopes with no (or very weak) gamma-ray yields. The combination of high-efficiency detection of charged particle emission in a liquid scintillation cocktail coupled with the low-background environment of an appropriately designed shield located in a clean underground laboratory provides the opportunity for increased-sensitivity measurements of a range of isotopes. To take advantage of the 35m-water-equivalent overburden of the underground laboratory, a series of simulations have evaluated the scintillation counter's shield design requirements to assess the possible background rate achievable. This report presents the design and background evaluation for a shallow underground, low background liquid scintillation counter design for sample measurements.
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66
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Kossert K, Mougeot X. The importance of the beta spectrum calculation for accurate activity determination of ⁶³Ni by means of liquid scintillation counting. Appl Radiat Isot 2015; 101:40-43. [PMID: 25827946 DOI: 10.1016/j.apradiso.2015.03.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 03/14/2015] [Accepted: 03/20/2015] [Indexed: 10/23/2022]
Abstract
The activity concentration of a (63)Ni solution was determined by means of two liquid scintillation counting techniques: the TDCR method and the CIEMAT/NIST efficiency tracing technique. The results of both methods are in excellent agreement, provided that the (63)Ni beta spectrum calculation accounts for the atomic exchange effect. Thus, new beta spectrum calculations resolve a discrepancy that has been found in previous analyses. The influence of the computed beta spectrum on the final uncertainty of the activity concentration is discussed.
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Affiliation(s)
- Karsten Kossert
- Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany.
| | - Xavier Mougeot
- CEA, LIST, Laboratoire National Henri Becquerel, F-91191 Gif-sur-Yvette, France
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67
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Eikenberg J, Beer H, Jäggi M. Determination of (210)Pb and (226)Ra/(228)Ra in continental water using HIDEX 300SL LS-spectrometer with TDCR efficiency tracing and optimized α/β-discrimination. Appl Radiat Isot 2014; 93:64-9. [PMID: 24637085 DOI: 10.1016/j.apradiso.2014.02.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 02/24/2014] [Accepted: 02/25/2014] [Indexed: 11/21/2022]
Abstract
An analytical method for determination of (210)Pb, (226)Ra and (228)Ra is presented based on adsorption on 3M Empore RadDiscs, and measurement applying liquid scintillation spectrometry (LSC) after elution. The LSC measurement was performed with optimized α/β-discrimination and isotope standardization using the triple to double coincidence ratio (TDCR). The consistency of measurement results between radioactive parent-daughter pairs (210)Pb/(210)Bi, (226)Ra/(222)Rn and (228)Ra/(228)Ac was checked in long-term counting experiments and the influence ofinterference of in-growing daughters from (226)Ra into the β-spectrum of (228)Ra+(228)Ac was studied as well. Recommendations for optimized LSC (228)Ra measurement besides presence of (226)Ra are given.
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Barlas Simsek F, Cagatay MN. Geochronology of lake sediments using (210)Pb with double energetic window method by LSC: an application to Lake Van. Appl Radiat Isot 2014; 93:126-33. [PMID: 24593926 DOI: 10.1016/j.apradiso.2014.01.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 10/01/2013] [Accepted: 01/28/2014] [Indexed: 10/25/2022]
Abstract
In this study the age and sediment accumulation rates of the lake sediment were calculated by using the (210)Pb concentrations through the sediment core. The specific activity of (210)Pb for each sediment section was determined by LSC with double energetic window method which relies on the direct determination of (210)Pb without waiting for the in growth of (210)Po from (210)Pb. For the successful determination of this radionuclide two counting windows were optimized to eliminate the overlapping of the beta spectra of (210)Pb and (210)Bi.
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Affiliation(s)
- F Barlas Simsek
- Istanbul Technical University, Eurasia Institute of Earth Sciences, Maslak, Istanbul, Turkey; Turkish Atomic Energy Authority, Çekmece Nuclear Research and Training Center, 34303 İstanbul, Turkey.
| | - M N Cagatay
- İstanbul Technical University, EMCOL, Faculty of Mining, Maslak, İstanbul, Turkey
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69
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Feng XG, He QG, Wang JC, Chen J. A method for optimum PSA setting in the absence of a pure α or β emitter and its application in the determination of (237)Np/(233)Pa. Appl Radiat Isot 2014; 93:114-9. [PMID: 24582116 DOI: 10.1016/j.apradiso.2014.01.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Revised: 09/24/2013] [Accepted: 01/27/2014] [Indexed: 10/25/2022]
Abstract
In the application of liquid scintillation counting (LSC), the α/β discrimination is carried out with the function of pulse shape analysis (PSA), which requires the setting of the optimum PSA level. The optimum PSA are usually determined by the generation of cross-over plots, whereby a pair of vials, one containing a pure α emitter and the other a pure β emitter, is counted. However, in some cases such as the determination of (237)Np/(233)Pa, a pure α emitter or a pure β emitter is not available. Therefore, we have developed a new approach to set the optimum PSA by measuring the sample itself of mixed α/β emitters. The count rate of the sample in the α-multi-channel analyzer changes monotonically with the increase of the PSA, and there is always an inflection point which is related to the optimum PSA. By fitting the data near the inflection point with the function y=ax(3)+bx(2)+cx+d, we can obtain the optimum PSA as -b/(3a), which can be used to determine the radioactivity of (237)Np/(233)Pa. The results obtained with this new approach were in good agreement with those obtained by HPGe γ spectrometry that was calibrated with an LSC sample of (237)Np/(233)Pa under a radioactive secular equilibrium. The new approach is promising to be used in simultaneous determination of gross α and β emitters, especially in the absence of a pure α or β emitter.
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Affiliation(s)
- Xiao-gui Feng
- Institute of Nuclear and New Energy Technology, Tsinghua University, PO Box 1021, 102201 Beijing, PR China.
| | - Qian-ge He
- Institute of Nuclear and New Energy Technology, Tsinghua University, PO Box 1021, 102201 Beijing, PR China
| | - Jian-chen Wang
- Institute of Nuclear and New Energy Technology, Tsinghua University, PO Box 1021, 102201 Beijing, PR China
| | - Jing Chen
- Institute of Nuclear and New Energy Technology, Tsinghua University, PO Box 1021, 102201 Beijing, PR China
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70
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Mitev K, Zhivkova V, Pressyanov D, Georgiev S, Dimitrova I, Gerganov G, Boshkova T. Liquid scintillation counting of polycarbonates: a sensitive technique for measurement of activity concentration of some radioactive noble gases. Appl Radiat Isot 2014; 93:87-95. [PMID: 24559941 DOI: 10.1016/j.apradiso.2014.01.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 10/21/2013] [Accepted: 01/28/2014] [Indexed: 11/16/2022]
Abstract
This work explores the application of the liquid scintillation counting of polycarbonates for measurement of the activity concentration of radioactive noble gases. Results from experimental studies of the method are presented. Potential applications in the monitoring of radioactive noble gases are discussed.
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Affiliation(s)
- K Mitev
- Laboratory of Dosimetry and Radiation Protection, Faculty of Physics, Sofia University "St. Kliment Ohridski", 5 James Bourchier Blvd, 1164 Sofia, Bulgaria.
| | - V Zhivkova
- Kozloduy Nuclear Power Plant, PP1, 3321 Kozloduy, Bulgaria
| | - D Pressyanov
- Laboratory of Dosimetry and Radiation Protection, Faculty of Physics, Sofia University "St. Kliment Ohridski", 5 James Bourchier Blvd, 1164 Sofia, Bulgaria
| | - S Georgiev
- Laboratory of Dosimetry and Radiation Protection, Faculty of Physics, Sofia University "St. Kliment Ohridski", 5 James Bourchier Blvd, 1164 Sofia, Bulgaria
| | - I Dimitrova
- Laboratory of Dosimetry and Radiation Protection, Faculty of Physics, Sofia University "St. Kliment Ohridski", 5 James Bourchier Blvd, 1164 Sofia, Bulgaria
| | - G Gerganov
- Laboratory of Dosimetry and Radiation Protection, Faculty of Physics, Sofia University "St. Kliment Ohridski", 5 James Bourchier Blvd, 1164 Sofia, Bulgaria
| | - T Boshkova
- Laboratory of Dosimetry and Radiation Protection, Faculty of Physics, Sofia University "St. Kliment Ohridski", 5 James Bourchier Blvd, 1164 Sofia, Bulgaria
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71
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Cassette P, Tartès I. Experimental study of the influence of the counter and scintillator on the universal curves in the cross-efficiency method in LSC. Appl Radiat Isot 2014; 87:32-7. [PMID: 24461555 DOI: 10.1016/j.apradiso.2013.11.128] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 11/22/2013] [Indexed: 11/21/2022]
Abstract
The cross-efficiency method in LSC is one of the approaches proposed for the extension of the Système International de Référence (SIR) to radionuclides emitting no gamma radiation. This method is based on a so-called "universal cross-efficiency curve", establishing a relationship between the detection efficiency of the radionuclide to be measured and the detection efficiency of a suitable tracer. This paper reports a study at LNHB on the influence of the scintillator and of the LS counter on the cross-efficiency curves. This was done by measuring the cross-efficiency curves obtained for (63)Ni and (55)Fe vs. (3)H, using three different commercial LS counters (Guardian 1414, Tricarb 3170 and Quantulus 1220), three different liquid scintillator cocktails (Ultima Gold, Hionic Fluor and PicoFluor 15 from Perkin Elmer(®)), and for chemical and colour-quenched sources. This study shows that these cross-efficiency curves are dependent on the scintillator, on the counter used and on the nature of the quenching phenomenon, and thus cannot definitively be considered as "universal".
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72
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Chen YT, Lu CJ. Effects of tetrachloroethene on the measurement of radon in water with liquid scintillation counting method. J Environ Radioact 2014; 127:26-33. [PMID: 24125902 DOI: 10.1016/j.jenvrad.2013.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 09/23/2013] [Accepted: 09/26/2013] [Indexed: 06/02/2023]
Abstract
This study investigated the effects of tetrachloroethene (PCE) on radon measurements that employed the liquid scintillation counting (LSC) method referring to 7500-Rn B of Standard Methods for the Examination of Water and Wastewater. Laboratory-produced radon-enriched water was used to compare the counting rates of the radon water with and without PCE addition, and groundwater samples from a site contaminated by chlorinated solvents were used to investigate the application of the laboratory experiments. The results showed that the major factor reducing counting efficiency was resulted from the interaction between PCE and a cocktail through the quench effect. The counting rate showed an exponentially decreasing trend when PCE addition was increased. The results indicated that a small addition of PCE reduced the counting rate considerably. An alternative energy channel 500-1000 to the optimal channel was suggested to attenuate the quench effect on radon measurement. The quench effect was also observed on samples from a site contaminated by chlorinated solvents. The concepts and procedures presented in this study are a reference for future research on the topic of chlorinated solvents or other quench chemicals involving in radon measurement.
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Affiliation(s)
- Yao-Tsung Chen
- Department of Cosmetic Science and Application, Lan Yang Institute of Technology, No. 79, Fushin Rd., Touchen Town, Yilan County 261, Taiwan, ROC.
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73
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Dziel T, Broda R, Ziemek T, Muklanowicz A, Listkowska A. Standardization of Sm-153 solution by absolute methods. Appl Radiat Isot 2014; 87:19-23. [PMID: 24331858 DOI: 10.1016/j.apradiso.2013.11.054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 11/18/2013] [Indexed: 11/20/2022]
Abstract
Standardization of (153)Sm by 4π(LS)-γ coincidence and anticoincidence counting and the CIEMAT/NIST method in three LS-counters is presented. This short half-life radionuclide is applied in tumor therapy and bone pain palliation. A simplified disintegration scheme of (153)Sm was applied in the calculation of the counting efficiency. Standard uncertainties of 0.4% for the (153)Sm measurements by the 4π(LS)-γ coincidence and anticoincidence techniques and 0.7% by the C/N method were evaluated, respectively. An agreement of the standardization results by both methods within the respective uncertainties was obtained. The half-life of (153)Sm of (1.92895±0.00024) days was determined during one month of measurements and correction for europium isotope impurities by the C/N method in the TriCarb 2910 LS-counter.
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