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Zhao G, Shao Y, Luo M, Xu D, Li D, Liu Z, Ma L. Research progress on the analysis and application of radioactive hot particle. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 270:107313. [PMID: 37857023 DOI: 10.1016/j.jenvrad.2023.107313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/21/2023]
Abstract
Radioactive hot particle is the particulate form of nuclear material that exists in the environment. The U, Pu, Am, Cs, and other radionuclides isotope in the hot particle contain abundant and accurate fingerprint information, such as the origin and age of the nuclear material. The acquisition and analysis of the key information in the hot particle can be equivalent to the analysis of bulk nuclear material, which could directly reflect the real situation of nuclear activities. Therefore, the single particle analysis of hot particles has become an irreplaceable key technology in nuclear safeguards inspection. The rapid identification, screening, locating, and accurate isotope analysis of hot particles from a large number of particles dispersed in environmental media or on the surface of other materials are one of the most important research field in nuclear emergency. In this review, the research process of the analytical methods for hot particles in the last decade was summarized, including the physical character of hot particles, and the techniques of localization, screening, and extraction of hot particles. Furthermore, we also focused on the mass spectrometry technology for the analysis of hot particle. The advantages and disadvantages of the most used mass spectrometry were summarized. Finally, the research trend for hot particle analysis methods was proposed.
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Affiliation(s)
- Guifang Zhao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China; State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yang Shao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Min Luo
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Diandou Xu
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
| | - Duohong Li
- State Nuclear Security Technology Center, Beijing, 102401, China
| | - Zhiming Liu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Lingling Ma
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
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Jiao X, Dong Z, Baccolo G, Li F, Wei T, Li J, Qin X. Insights on the distribution and environmental implications of the radio-isotope 235U in surface soils and glaciers of the Tibetan Plateau. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 317:120824. [PMID: 36493938 DOI: 10.1016/j.envpol.2022.120824] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/14/2022] [Accepted: 12/04/2022] [Indexed: 06/17/2023]
Abstract
Atom ratio between 235U and 238U is often used as an indicator of U contamination as the isotopic signature of products generated by the nuclear and military industry significantly vary from the natural isotopic ratio of U. In this study, surface soils and glaciers samples were collected in the Tibetan Plateau (TP) and its surrounding areas and analyzed for U isotopic composition. Results show that the 235U/238U atom ratios in the surface soils of the TP ranges from 0.007122 to 0.007615, with an average value of 0.007378 ± 0.00011; while in the snow/ice dust from high-altitude glaciers it ranges from 0.007254 to 0.007687, with an average value of 0.007345 ± 0.000128. These ratios are slightly higher than the typical crustal value, indicating that the TP was affected by an anthropogenic input of 235U, especially in its northeast and southwest sectors. The variability of our results suggests that the spatial distribution of this contamination is not uniform, pointing to differences in the potential sources and transmission paths of radioactive particles. Combining the knowledge of past tests and activities conducted in the geographic areas around the TP with the knowledge of prevailing winds, we hypothesize that the observed 235U contamination in the TP surface soils and glaciers may have originated mainly from the previous nuclear related activities in surrounding areas (e.g., north Gobi Desert and South Asia). In addition, the horizontal and vertical wind field around the Tibetan Plateau, as well as the atmospheric aerosol optical thickness data also demonstrated the possible transport paths of the radionuclides, that is, originated from in northern Gobi desert and South Asia and reached the TP crossing the Himalayas.
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Affiliation(s)
- Xiaoyu Jiao
- State Key Laboratory of Cryosphere Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhiwen Dong
- State Key Laboratory of Cryosphere Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Giovanni Baccolo
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, Villigen, Switzerland
| | - Fangzhou Li
- College of Environmental Science and Engineering, Peking University, Beijing, China
| | - Ting Wei
- State Key Laboratory of Cryosphere Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Jing Li
- State Key Laboratory of Cryosphere Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Xiang Qin
- State Key Laboratory of Cryosphere Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; Qilian Mountain Glacier and Ecological Environment Research Station, Chinese Academy of Sciences, Lanzhou, 730000, China
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Straub MD, Arnold J, Fessenden J, Kiplinger JL. Recent Advances in Nuclear Forensic Chemistry. Anal Chem 2020; 93:3-22. [DOI: 10.1021/acs.analchem.0c03571] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Mark D. Straub
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Los Alamos National Laboratory, Chemistry Division, Mailstop J-514, Los Alamos, New Mexico 87545, United States
| | - John Arnold
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Julianna Fessenden
- Los Alamos National Laboratory, XTD Division, Los Alamos, New Mexico 87545, United States
| | - Jaqueline L. Kiplinger
- Los Alamos National Laboratory, Chemistry Division, Mailstop J-514, Los Alamos, New Mexico 87545, United States
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McGuire C, Dale P, Copplestone D, Wilson C, Tyler A. Characterising radium-226 particles from legacy contamination to support radiation dose assessments. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2020; 212:106127. [PMID: 31885362 DOI: 10.1016/j.jenvrad.2019.106127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 11/29/2019] [Accepted: 11/29/2019] [Indexed: 06/10/2023]
Abstract
Radioactive particles are physically discrete sources of radioactivity that have been released into the environment as a result of past emergencies, events and practices. As the release of radioactive particles is often unplanned, the source term has not been characterised, and the potential radiation doses have not been prospectively assessed. If a plausible exposure pathway exists, radioactive particles in the environment may present a hazard to the public depending on their radiological, physical and chemical characteristics. Given their physically discrete nature, standard assessment approaches such as dispersion and transfer modelling of liquid and gaseous radioactive releases, are not appropriate for radioactive particles. The challenge for national regulatory authorities is to calculate potential radiation doses from unplanned releases of radioactive particles into the environment, assess whether the doses are relevant to radiological protection and decide whether actions are required to reduce potential doses. To address this challenge, this paper presents the approach being adopted to radiologically, physically and chemically characterise Ra-226 particles from a contaminated legacy site using gamma spectrometry, optical macroscopy and SEM-EDS. The use of particle characterisation data to support radiation dose assessments is discussed and consideration is given to radioactive particles in the context of radiological protection.
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Affiliation(s)
- C McGuire
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom; Scottish Environment Protection Agency, Strathallan House, Castle Business Park, Stirling, FK9 4TZ, United Kingdom.
| | - P Dale
- Scottish Environment Protection Agency, Strathallan House, Castle Business Park, Stirling, FK9 4TZ, United Kingdom
| | - D Copplestone
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - C Wilson
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - A Tyler
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
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Sancho C, García-Tenorio R. Radiological evaluation of the transuranic remaining contamination in Palomares (Spain): A historical review. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2019; 203:55-70. [PMID: 30865871 DOI: 10.1016/j.jenvrad.2019.02.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 02/23/2019] [Indexed: 06/09/2023]
Abstract
This paper shows the studies carried out in Palomares (Almería, Spain) following the ground dispersion of nuclear material as a result of the air crash accident that took place in 1966, in which four nuclear bombs were involved. As a consequence of the Palomares accident, plutonium (Pu) and uranium (U) were dispersed over an area of approximately 2.3 km2 due to the chemical explosion of two of them. The most relevant activities carried out by CIEMAT, along with other national and international institutions in the Palomares scenario are detailed. These activities, performed for over 50 years, focus mainly in the characterization of the contamination source, in the continuous environmental and personal radiological monitoring programs, in the construction of a detailed superficial and 3-D mapping distribution of the remaining contamination and in the evaluation of the bioavailability of the transuranics still remaining in the area.
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Affiliation(s)
- C Sancho
- Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.
| | - R García-Tenorio
- Centro Nacional de Aceleradores, CNA, (Universidad de Sevilla-Junta de Andalucía-CSIC), Sevilla, Spain
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Cagno S, Hellemans K, Lind OC, Skipperud L, Janssens K, Salbu B. LA-ICP-MS for Pu source identification at Mayak PA, the Urals, Russia. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2014; 16:306-312. [PMID: 24424783 DOI: 10.1039/c3em00531c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Information on Pu in environmental samples is traditionally based on the determination of the (240+239)Pu activity via Alpha Spectrometry (AS). A large number of alpha spectrometry sources (planchettes) containing radiochemically separated Pu are therefore stored worldwide and are available for further analyses. These archive samples represent a resource from which valuable information on isotopic composition of alpha emitters including Pu can be obtained. The relative abundances of Pu isotopes can be used to trace specific Pu sources and characterize the relative contributions of different Pu sources in a sample. Thus, in addition to the total (239+240)Pu activity, determination of the (240)Pu/(239)Pu ratio can provide valuable information on the nature of the Pu emitting sources. The Pu isotopic ratios can be determined by mass spectrometry techniques such as Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICPMS) or Accelerator Mass Spectrometry (AMS) that require dissolution and complete destruction of the material deposited on the planchettes. In this study Laser Ablation (LA)-quadrupole-ICP-MS has been employed for the analysis of (239)Pu/(240)Pu ratios from alpha-planchettes prepared from samples originating from the Mayak PA nuclear facility, Russia. The results are compared with data from AMS and show that the (240)Pu/(239)Pu ratios obtained by LA-ICP-MS can be utilized to distinguish weapons-grade Pu from civil reprocessing sources. Moreover, isotope ratio mapping can also be performed across the planchettes, allowing e.g. the visualization of possible inhomogeneities in the Pu-isotope distribution on their surface. Thus, this solid sample technique can be applied to extract additional information from existing archives of samples.
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Affiliation(s)
- S Cagno
- CERAD, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Ås, Norway.
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Webb-Robertson BJ, Corley C, McCue LA, Wahl K, Kreuzer H. Fusion of laboratory and textual data for investigative bioforensics. Forensic Sci Int 2013; 226:118-24. [PMID: 23313599 DOI: 10.1016/j.forsciint.2012.12.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 12/04/2012] [Accepted: 12/16/2012] [Indexed: 10/27/2022]
Abstract
Chemical and biological forensic programs focus on the identification of a threat and acquisition of laboratory measurements to determine how a threat agent may have been produced. However, to generate investigative leads, it might also be useful to identify institutions where the same agent has been produced by the same or a very similar process, since the producer of the agent may have learned methods at a university or similar institution. We have developed a Bayesian network framework that fuses hard and soft data sources to assign probability to production practices. It combines the results of laboratory measurements with an automatic text reader to scan scientific literature and rank institutions that had published papers on the agent of interest in order of the probability that the institution has the capability to generate the sample of interest based on laboratory data. We demonstrate the Bayesian network on an example case from microbial forensics, predicting the methods used to produce Bacillus anthracis spores based on mass spectrometric measurements and identifying institutions that have a history of growing Bacillus spores using the same or highly similar methods. We illustrate that the network model can assign a higher posterior probability than expected by random chance to appropriate institutions when trained using only a small set of manually analyzed documents. This is the first example of an automated methodology to integrate experimental and textual data for the purpose of investigative forensics.
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Affiliation(s)
- Bobbie-Jo Webb-Robertson
- Computational Biology & Bioinformatics, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA 99352, USA.
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Morphology of actinide-rich particles released from the BOMARC accident and collected from soil post remediation. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2177-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Stanley FE, Stalcup AM, Spitz HB. A brief introduction to analytical methods in nuclear forensics. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-1927-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Ketterer ME, Zheng J, Yamada M. Applications of Transuranics as Tracers and Chronometers in the Environment. ADVANCES IN ISOTOPE GEOCHEMISTRY 2012. [DOI: 10.1007/978-3-642-10637-8_20] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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12
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Jiménez-Ramos MC, Hurtado S, Chamizo E, García-Tenorio R, León-Vintró L, Mitchell PI. (239)Pu, (240)Pu, and (241)Am determination in hot particles by low level gamma-spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:4247-4252. [PMID: 20441142 DOI: 10.1021/es100425x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A nondestructive method based on low-energy, high-resolution photon spectrometry is presented which allows accurate determination of (239)Pu, (240)Pu, and (241)Am (as a daughter of (241)Pu) activities in radioactive particles containing relatively high levels of plutonium isotopes. The proposed method requires only one measurement for the establishment of an absolute efficiency curve. Since the density and composition of the radioactive particles of interest may vary, a self-absorption correction is required for the accurate determination of isotopic activities and ratios. This correction is carried out for each individual particle using the convenient gamma-ray emissions of (241)Am.
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Qiao J, Hou X. Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2010; 101:244-9. [PMID: 20004047 DOI: 10.1016/j.jenvrad.2009.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 11/23/2009] [Accepted: 11/25/2009] [Indexed: 05/10/2023]
Abstract
Fractionation of plutonium isotopes ((238)Pu, (239,240)Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially designed extraction column. Plutonium in the fractions from the sequential extraction was separated by ion exchange chromatography and measured using alpha spectrometry. The analytical results show a higher mobility of plutonium in bio-shielding concrete, which means attention should be paid to the treatment and disposal of nuclear waste from decommissioning.
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Affiliation(s)
- Jixin Qiao
- Radiation Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark, DK-4000 Roskilde, Denmark
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Lindahl P, Lee SH, Worsfold P, Keith-Roach M. Plutonium isotopes as tracers for ocean processes: a review. MARINE ENVIRONMENTAL RESEARCH 2010; 69:73-84. [PMID: 19773079 DOI: 10.1016/j.marenvres.2009.08.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Revised: 08/17/2009] [Accepted: 08/18/2009] [Indexed: 05/28/2023]
Abstract
Since the first nuclear weapons tests in the 1940s, pulsed inputs of plutonium isotopes have served as excellent tracers for understanding sources, pathways, dynamics and the fate of pollutants and particles in the marine environment. Due to the well-defined spatial and temporal inputs of Pu, the long half-lives of (240)Pu and (239)Pu and its unique chemical properties, Pu is a potential tracer for various physical and biogeochemical ocean processes, including circulation, sedimentation and biological productivity, and hence a means of assessing the impacts of global climate change. Due to the source dependency of the Pu isotopic signature, plutonium isotopes are beginning to be exploited as tools for the evaluation and improvement of regional and global ocean models that will enhance understanding of past and future changes in the oceans. This paper addresses the major sources of Pu and the physical and biogeochemical behaviour in the marine environment. Finally, the use of Pu isotopes as tracers for various oceanic processes (e.g. water mass transport, particle export, and sedimentation) is considered.
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Affiliation(s)
- Patric Lindahl
- Marine Environment Research Department, Korea Ocean Research and Development Institute, Ansan, P.O. Box 29, Seoul 425-600, Republic of Korea.
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Hamilton TF, Jernströem J, Martinelli RE, Kehl SR, Eriksson M, Williams RW, Bielewski M, Rivers AN, Brown TA, Tumey SJ, Betti M. Frequency distribution, isotopic composition and physical characterization of plutonium-bearing particles from the Fig-Quince zone on Runit Island, Enewetak Atoll. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-009-0237-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Martín Sánchez A, Sáenz García G, Jurado Vargas M. Study of self-absorption for the determination of gross alpha and beta activities in water and soil samples. Appl Radiat Isot 2009; 67:817-20. [DOI: 10.1016/j.apradiso.2009.01.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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239, 240, 241Pu fingerprinting of plutonium in western US soils using ICPMS: solution and laser ablation measurements. Anal Bioanal Chem 2007; 390:521-30. [DOI: 10.1007/s00216-007-1741-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2007] [Revised: 11/06/2007] [Accepted: 11/06/2007] [Indexed: 11/25/2022]
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18
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Ranebo Y, Eriksson M, Tamborini G, Niagolova N, Bildstein O, Betti M. The use of SIMS and SEM for the characterization of individual particles with a matrix originating from a nuclear weapon. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2007; 13:179-90. [PMID: 17490500 DOI: 10.1017/s1431927607070353] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Accepted: 02/02/2007] [Indexed: 05/15/2023]
Abstract
The application of scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS) for characterization of mixed plutonium and uranium particles from nuclear weapons material is presented. The particles originated from the so-called Thule accident in Greenland in 1968. Morphological properties have been studied by SEM and two groups were identified: a "popcorn" structure and a spongy structure. The same technique, coupled with an energy-dispersive X-ray (EDX) spectrometer, showed a heterogeneous composition of Pu and U in the surface layers of the particles. The SIMS depth profiles revealed a varying isotopic composition indicating a heterogeneous mixture of Pu and U in the original nuclear weapons material itself. The depth distributions agree with synchrotron-radiation-based mu-XRF (X-ray fluorescence microprobe) measurements on the particle (Eriksson, M., Wegryzynek, D., Simon, R., & Chinea-Cano, E., in prep.) when a SIMS relative sensitivity factor for Pu to U of 6 is assumed. Different SIMS identified isotopic ratio groups are presented, and the influence of interferences in the Pu and U mass range are estimated. The study found that the materials are a mixture of highly enriched 235U (235U:238U ratio from 0.96 to 1.4) and so-called weapons grade Pu (240Pu:239Pu ratio from 0.028 to 0.059) and confirms earlier work reported in the literature.
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Affiliation(s)
- Ylva Ranebo
- European Commission, Joint Research Centre, Institute for Transuranium Elements, D-76125 Karlsruhe, Germany.
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