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Wabwile JM, Angeyo HK, Massop AD. Exploring band-free Raman microspectrometry combined with PCA and MCR-ALS for size-resolved forensic analysis of uranium in aerosols in a model nuclear atmosphere. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 270:107295. [PMID: 37741154 DOI: 10.1016/j.jenvrad.2023.107295] [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: 06/06/2023] [Revised: 09/10/2023] [Accepted: 09/11/2023] [Indexed: 09/25/2023]
Abstract
Achieving non-destructive micrometer-scale molecular and structural analysis of uranic materials in atmospheric aerosols with traditional methodologies is a challenge. Spatially resolved analysis of uranium in actinide-bearing aerosols is critical for nuclear forensics. Although laser Raman microspectrometry enables this, for the normally low uranium concentrations in the aerosols the spectra are indiscernible (band-free) against pronounced background: trace analysis requires a push in analytical strategy. We combined laser Raman microspectrometry (utilizing two lasers (λ = 532 nm, λ = 785 nm)) with principal component analysis (PCA) and multivariate curve resolution-alternate least squares (MCR-ALS) to perform size-resolved analysis of uranium in aerosols. Uranium-specific Raman scatter bands corresponding to uranyl nitrate (860 cm-1), uranium sulphate (868 cm-1), uranyl chloride (816 cm-1) and uranium trioxide (839 cm-1) were detected. The 816 cm-1, 854 cm-1, 868 cm-1 bands were resolved by MCR-ALS and used to identify and map uranium in PM4.5 size aerosols. Based on spectral feature selection of the signature bands, PCA identified two sources of aerosol particles in model nuclear atmosphere - Sea spray for PM4.5 and re-suspension of 'nuclear' dust from a rare earth element (REE) mine for PM2.5. The MCR-ALS-resolved uranium bands showed the potential for attributive nuclear forensic analysis.
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Reilly SD, Patton GM, Murillo J, Oldham WJ, Miller JL, LaMont SP, Sanborn ME, May I, Gaunt AJ, Hanson SK. Trace Actinide Signatures of a Bulk Neptunium Sample. Anal Chem 2023. [PMID: 37261935 DOI: 10.1021/acs.analchem.3c01682] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In nuclear forensic analyses, measurements of actinide elements in a sample can assist with identifying interdicted or unknown materials. While these radiochemical signatures have been extensively investigated in uranium materials, less is known about bulk neptunium samples. This paper describes the measurement of trace actinide concentrations and isotopic profiles in a 237Np oxide sample. Uranium, plutonium, americium, and curium concentrations and isotopic profiles in the sample were determined and deemed potentially useful for distinguishing different sources of 237Np. Several different potential radiochronometry systems were also investigated; discordant results indicate that the Np sample was never completely purified of other actinide elements, or that subsequent contamination of the sample occurred. Few prior studies of neptunium materials have been reported, and these data suggest that trace actinide constituents could provide unique signatures to identify material out of regulatory control.
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He H, Zhao X, Zhang Y, Zhao L, Hu R, Li L. Determination of rare earth elements in uranium ores by ICP-MS after total dissolution with NH4F and matrix separation with TRU resin. J Radioanal Nucl Chem 2023. [DOI: 10.1007/s10967-023-08863-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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4
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Varga Z, Nicholl A, Wallenius M, Mayer K, Mock T. Propagation and variation of material characteristics during the uranium ore concentrate production at Dolní Rožinka, Czech Republic. J Radioanal Nucl Chem 2023. [DOI: 10.1007/s10967-023-08781-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
AbstractIn the framework of the European Commission Support Programme to the International Atomic Energy Agency (EC SP task A1753) 20 samples were obtained from the Dolní Rožínka (DIAMO, Czech Republic) uranium milling facility. The sampling procedure followed stepwise the uranium production and purification from the U ore to uranium ore concentrate (yellow cake) end-product. Elemental concentrations, rare-earth elemental pattern, anion concentrations, morphology and isotope abundance ratios of S, Sr, Pb and U were measured at each sampling stage. The purpose of the measurements was to investigate the applicability of various material characteristics for authentication, propagation and variation of these parameters, and to identify the relevant signatures for nuclear forensics and safeguards during the uranium production.
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Determining provenance of uranium ore concentrates using 143Nd/144Nd. Talanta 2022. [DOI: 10.1016/j.talanta.2022.124088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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6
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Park JH. Experimental evaluation of data integration methods for isotopic analysis of uranium with ultra-trace levels using TIMS. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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7
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Barry A, Thomson S, Dimayuga I, Chaudhuri A, Do T. Isotope ratio method: state-of-the-art of forensic applications to CBRNE materials. CANADIAN SOCIETY OF FORENSIC SCIENCE JOURNAL 2022. [DOI: 10.1080/00085030.2022.2054109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Aaron Barry
- Canadian Nuclear Laboratories, Chalk River, ON, Canada
| | | | - Ike Dimayuga
- Canadian Nuclear Laboratories, Chalk River, ON, Canada
| | | | - Than Do
- Canadian Nuclear Laboratories, Chalk River, ON, Canada
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Varga Z, Wallenius M, Krachler M, Rauff-Nisthar N, Fongaro L, Knott A, Nicholl A, Mayer K. Trends and perspectives in Nuclear Forensic Science. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2021.116503] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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9
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Validation of in-house procedure for monitoring rare earth elements and lead elemental impurities in uranium materials. J Radioanal Nucl Chem 2021. [DOI: 10.1007/s10967-021-07926-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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10
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Pastoor KJ, Kemp RS, Jensen MP, Shafer JC. Progress in Uranium Chemistry: Driving Advances in Front-End Nuclear Fuel Cycle Forensics. Inorg Chem 2021; 60:8347-8367. [PMID: 33619961 DOI: 10.1021/acs.inorgchem.0c03390] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The front-end of the nuclear fuel cycle encompasses several chemical and physical processes used to acquire and prepare uranium for use in a nuclear reactor. These same processes can also be used for weapons or nefarious purposes, necessitating the need for technical means to help detect, investigate, and prevent the nefarious use of nuclear material and nuclear fuel cycle technology. Over the past decade, a significant research effort has investigated uranium compounds associated with the front-end of the nuclear fuel cycle, including uranium ore concentrates (UOCs), UF4, UF6, and UO2F2. These efforts have furthered uranium chemistry with an aim to expand and improve the field of nuclear forensics. Focus has been given to the morphology of various uranium compounds, trace elemental and chemical impurities in process samples of uranium compounds, the degradation of uranium compounds, particularly under environmental conditions, and the development of improved or new techniques for analysis of uranium compounds. Overall, this research effort has identified relevant chemical and physical characteristics of uranium compounds that can be used to help discern the origin, process history, and postproduction history for a sample of uranium material. This effort has also identified analytical techniques that could be brought to bear for nuclear forensics purposes. Continued research into these uranium compounds should yield additional relevant chemical and physical characteristics and analytical approaches to further advance front-end nuclear fuel cycle forensics capabilities.
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Affiliation(s)
- Kevin J Pastoor
- Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, United States
| | - R Scott Kemp
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mark P Jensen
- Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, United States.,Nuclear Science and Engineering Program, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Jenifer C Shafer
- Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, United States.,Nuclear Science and Engineering Program, Colorado School of Mines, Golden, Colorado 80401, United States
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11
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Kayzar-Boggs TM, Kinman WS, Bostick DA, Cardon A, Foley RR, Hexel CR, King-Lopez R, Lindvall RE, Marks N, Sharp MA, Ticknor BW. Exploring the use of thorium isotope compositions and concentrations as nuclear forensic signatures for uranium ore concentrates. J Radioanal Nucl Chem 2021. [DOI: 10.1007/s10967-020-07534-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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12
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Shollenberger QR, Borg LE, Ramon EC, Sharp MA, Brennecka GA. Samarium isotope compositions of uranium ore concentrates: A novel nuclear forensic signature. Talanta 2021; 221:121431. [DOI: 10.1016/j.talanta.2020.121431] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 11/25/2022]
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13
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Pastoor KJ, Robinson SL, Greenwell RA, Quintero Hilsaca CV, Shafer JC, Jensen MP. Understanding uranium oxide hardening during prolonged storage. RADIOCHIM ACTA 2020. [DOI: 10.1515/ract-2020-0044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Uranium ore concentrates (UOCs), the product of uranium mining and milling, are primarily comprised of uranium oxide (U3O8 and UO2) or peroxide (UO4·4H2O and UO4·2H2O) compounds. Following production, UOCs are typically placed in storage until they are converted to uranium hexafluoride (UF6) at a uranium conversion facility. In this study, the chemical changes responsible for an interesting hardening phenomenon observed in UOCs stored for prolonged periods was investigated to understand underlying causes. Powder X-ray diffraction and thermogravimetric analysis were used to characterize free-flowing and hardened UOC samples and revealed the hardened material had undergone hydration and oxidation as indicated by increased moisture content and the presence of metaschoepite [(UO2)4O(OH)6](H2O)5 and/or schoepite [(UO2)4O(OH)6](H2O)6. Additionally, an aging study found metaschoepite in UOCs after 3 months exposure to a high relative humidity environment. The same study found agglomerated, but not fully hardened, material in nearly all aged UOCs samples. These results suggest metaschoepite and schoepite are indicative of UOCs exposed to elevated levels of H2O during storage. Lastly, a drying/calcining study of hardened U3O8 material demonstrated a means of remediation and identified an intermediate compound of potential interest, dehydrated schoepite. Dehydrated schoepite results from heating metaschoepite or schoepite between 100 and 300 °C and indicates partial reversal of hardened U3O8 to its original condition.
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Affiliation(s)
- Kevin J. Pastoor
- Department of Chemistry , Colorado School of Mines , Golden , CO 80401 , USA
| | | | | | | | - Jenifer C. Shafer
- Department of Chemistry , Colorado School of Mines , Golden , CO 80401 , USA
| | - Mark P. Jensen
- Department of Chemistry , Nuclear Science and Engineering Program , Colorado School of Mines , Golden , CO 80401 , USA
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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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Rare Earth Element Determination in Uranium Ore Concentrates Using Online and Offline Chromatography Coupled to ICP-MS. MINERALS 2020. [DOI: 10.3390/min10010055] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The determination of trace elements, particularly rare earth elements, in uranium ore concentrates (UOCs) is important as the pattern can be indictive ore characteristics. Presented here is a methodology for accurately quantifying rare earth elements (REE) in UOCs. To improve the measurement uncertainty, isotope dilution mass spectrometry (IDMS) was utilized over other quantification techniques such as external calibration or standard addition. The isotopic determinations were measured by inductively coupled plasma-mass spectrometry (ICP-MS). To obtain high-fidelity isotopic measurements, separation of the REE from the uranium matrix was achieved by high-performance ion chromatography (HPIC), reducing the isobaric interferences. After separation, the target analytes were analyzed in two different modalities. For high precision analysis, the separated analytes were collected and measured by ICP-MS in an “offline” fashion. For a rapid approach, the separated analytes were sent directly into an ICP-MS for “online” analysis. These methods have been demonstrated to accurately quantify the REE content in a well-characterized UOC sample.
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Achieving confidence in trace element analysis for nuclear forensic purposes: ICP-MS measurements using external calibration. J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-019-06795-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Abstract
In this work, problems arising from performing trace element analysis using inductively coupled plasma—mass spectrometry with low measurement uncertainties are addressed. It is shown that some reference materials certified for massic concentration of lanthanides may have either deviating concentrations or underestimated measurement uncertainties. It is also shown that the choice of methods for sample preparation and linear regression to perform external calibration is affecting the outcome of the measurement results and their uncertainties. The results show that, from the selection of methods investigated in this work, the lowest measurement uncertainties can be achieved by using weighted linear regression to evaluate the calibration function and gravimetric dilutions of samples.
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Multivariate Analysis Based on Geochemical, Isotopic, and Mineralogical Compositions of Uranium-Rich Samples. MINERALS 2019. [DOI: 10.3390/min9090537] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The chemical and isotopic (U, Pb, Sr) signatures for a suite (n = 23) of pristine (>80 wt. % UO2) and altered uraninite samples (>70–80 wt. % UO2) from various locations worldwide have been determined for the purpose of identifying potential fingerprints for nuclear forensic analysis. The characterization of the uraninite samples included determination of major, minor and trace element contents, Sr, Pb, and U isotopic compositions, and secondary mineral assemblages. Due to the multivariate approach adopted in this study, principal component analysis (PCA) has been employed to allow the direct comparison of multiple variable types. The PCA results indicate that the geological origin (sandstone, metamorphite, intrusive, granite and unconformity) of pristine uraninite can be readily identified utilizing various combinations of major and/or trace element concentrations with isotopic compositions.
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18
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Varga Z, Wallenius M, Nicholl A, Mayer K, Balan I, Benea V. Measurement of production date (age) of nanogram amount of uranium. J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-019-06705-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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19
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Analysis of geochemical basalts database as a simulant for uranium ore concentrates data: the Galaxy Serpent 3 Exercise. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-0831-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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20
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Vesterlund A, Ramebäck H. Avoiding polyatomic interferences in measurements of lanthanides in uranium material for nuclear forensic purposes. J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-019-06623-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Ha G, Heo G, Seo H, Choi Y. Development of a data-driven classification algorithm for fresh nuclear fuel forensics. J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-019-06517-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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22
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Measurement of the 231Pa/ 235U ratio for the age determination of uranium materials. J Radioanal Nucl Chem 2018; 318:1565-1571. [PMID: 30546184 PMCID: PMC6267122 DOI: 10.1007/s10967-018-6247-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Indexed: 12/04/2022]
Abstract
The paper describes the age (production date) determination of uranium reference materials using the 231Pa/235U ratio. Direct addition of 237Np in secular equilibrium with its 233Pa daughter was chosen instead of the regular milking of 237Np to avoid possible loss of Pa. Sample preparation consists of a fast, one-step procedure. The developed method using ICP-MS for the measurement of 231Pa is more precise than alpha spectrometry and is applicable for freshly produced low-enriched uranium materials. The measured ages are in good agreement with the reported production dates, thus the 231Pa/235U chronometer can be applied for validation of 230Th/234U in nuclear forensics and safeguards.
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23
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Trace impurity analysis in uranium oxide via hybrid quantification techniques—gravimetric standard addition and isotope dilution mass spectrometry. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-6106-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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24
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25
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Discrimination of uranium ore concentrates by chemometric data analysis to support provenance assessment for nuclear forensics applications. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-5912-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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26
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Experimental evaluation of the detection methods of thermal ionization mass spectrometry for isotopic analysis of ultra-trace level uranium. Microchem J 2018. [DOI: 10.1016/j.microc.2017.11.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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27
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Lavelle KB, Essex RM, Carney KP, Cessna JT, Hexel CR. A reference material for evaluation of 137 Cs radiochronometric measurements. J Radioanal Nucl Chem 2018; 318. [PMID: 30996507 DOI: 10.1007/s10967-018-6061-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new nuclear forensic reference material has been characterized as a standard for radiochronometric determination of the model purification date for 137Cs sources. The purification date of a radioactive source is a potentially diagnostic nuclear forensic signature for determining the provenance of a radioactive material. Reference values have been measured for the attributes needed to use the 137Cs/137Ba chronometer: the molality (reported here as nmol g-1) of 137Cs and of the radiogenic portion of 137Ba in the material (hereafter referred to as 137Ba*). All measurement results were decay-corrected to represent the composition of the material on the reference date of July 7, 2011. The molality of 137Cs is (0.7915 ± 0.0073) nmol g-1; this value was calculated from the massic activity of 137Cs, (348.4 ± 3.0) kBq g-1, as measured in the NIST 4π-γ secondary standard ionization chamber (previously calibrated by 4π-(e+x)-γ-coincidence efficiency extrapolation counting) and the evaluated half-life of 137Cs, (30.05 ± 0.08) years. The molality of 137Ba*, (1.546 ± 0.024) nmol g-1, was measured by isotope dilution mass spectrometry using the measured relative proportion of 138Ba in the material to apply a correction for the 137Ba contribution from natural Ba. A model age of (47.04 ± 0.56) years, corresponding to a model purification date of June 22, 1964 with an expanded uncertainty of 200 days is calculated from the reference material values. This age is consistent with the date engraved on the capsule that contained the 137Cs starting material and with a prior independent determination of the model purification date. A full discussion of the uncertainties of the reference material values is included.
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Affiliation(s)
- Kevin B Lavelle
- National Institute of Standards and Technology, 100 Bureau Dr., MS 8462, Gaithersburg, MD 20899-8462, USA
| | - Richard M Essex
- National Institute of Standards and Technology, 100 Bureau Dr., MS 8462, Gaithersburg, MD 20899-8462, USA
| | - Kevin P Carney
- Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415-2805, USA
| | - Jeffrey T Cessna
- National Institute of Standards and Technology, 100 Bureau Dr., MS 8462, Gaithersburg, MD 20899-8462, USA
| | - Cole R Hexel
- Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6181, USA
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