1
|
Ramirez NC, Collins SM. A new determination of the 68Ga half-life and evaluation of literature data. Appl Radiat Isot 2024; 203:111103. [PMID: 37977103 DOI: 10.1016/j.apradiso.2023.111103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/30/2023] [Accepted: 11/01/2023] [Indexed: 11/19/2023]
Abstract
Inconsistencies within the 68Ga half-life dataset have been repeatedly identified in nuclear decay data evaluations performed over the past decade. In this paper, a half-life has been determined using ionisation chambers measurements and HPGe gamma-ray spectrometry (T1/2 = 67.783(27) min). The current literature has been reviewed and possible causes of discrepancy have been identified, such as neglected contaminant effects, robustness of analysis, and underestimation of systematic effects. This could lead to a significant improvement of the half-life in future evaluations.
Collapse
Affiliation(s)
- N C Ramirez
- National Physical Laboratory, Hampton Road, Teddington, Middlesex, UK.
| | - S M Collins
- National Physical Laboratory, Hampton Road, Teddington, Middlesex, UK
| |
Collapse
|
2
|
Abstract
AbstractRadionuclides, whether naturally occurring or artificially produced, are readily detected through their particle and photon emissions following nuclear decay. Radioanalytical techniques use the radiation as a looking glass into the composition of materials, thus providing valuable information to various scientific disciplines. Absolute quantification of the measurand often relies on accurate knowledge of nuclear decay data and detector calibrations traceable to the SI units. Behind the scenes of the radioanalytical world, there is a small community of radionuclide metrologists who provide the vital tools to convert detection rates into activity values. They perform highly accurate primary standardisations of activity to establish the SI-derived unit becquerel for the most relevant radionuclides, and demonstrate international equivalence of their standards through key comparisons. The trustworthiness of their metrological work crucially depends on painstaking scrutiny of their methods and the elaboration of comprehensive uncertainty budgets. Through meticulous methodology, rigorous data analysis, performance of reference measurements, technological innovation, education and training, and organisation of proficiency tests, they help the user community to achieve confidence in measurements for policy support, science, and trade. The author dedicates the George Hevesy Medal Award 2020 to the current and previous generations of radionuclide metrologists who have devoted their professional lives to this noble endeavour.
Collapse
|
3
|
|
4
|
Massoud A, Derbalah A, El-Mehasseb I, Allah MS, Ahmed MS, Albrakati A, Elmahallawy EK. Photocatalytic Detoxification of Some Insecticides in Aqueous Media Using TiO 2 Nanocatalyst. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18179278. [PMID: 34501865 PMCID: PMC8431621 DOI: 10.3390/ijerph18179278] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/12/2021] [Accepted: 08/28/2021] [Indexed: 11/16/2022]
Abstract
The present study was performed to fabricate a titanium dioxide (TiO2) nanocatalyst with proper characteristics for the removal of some insecticides (dimethoate and methomyl) from aqueous media. A TiO2 catalyst of regular (TiO2-commercial-/H2O2/UV) or nano (TiO2-synthesized-/H2O2/UV) size was employed as an advanced oxidation process by combining it with H2O2 under light. Moreover, the total detoxification of insecticides after treatment with the most effective system (TiO2(s)/H2O2/UV) was also investigated through exploring the biochemical alterations and histopathological changes in the liver and kidneys of the treated rats. Interestingly, the present study reported that degradation rates of the examined insecticides were faster using the TiO2 catalyst of nano size. Complete degradation of the tested insecticides (100%) was achieved under the TiO2(s)/H2O2/UV system after 320 min of irradiation. The half-life values of the tested insecticides under H2O2/TiO2(c)/UV were 43.86 and 36.28 for dimethoate and methomyl, respectively, whereas under the H2O2/TiO2(c)/UV system, the half-life values were 27.72 and 19.52 min for dimethoate and methomyl, respectively. On the other hand, no significant changes were observed in the biochemical and histopathological parameters of rats administrated with water treated with TiO2(s)/H2O2/UV compared to the control, indicating low toxicity of the TiO2 nanocatalyst-. Altogether, the advanced oxidation processes using TiO2 nanocatalyst can be considered as a promising and effective remediation technology for the complete detoxification of methomyl and dimethoate in water. However, further future research is needed to identify the possible breakdown products and to verify the safety of the used nanomaterials.
Collapse
Affiliation(s)
- Ahmed Massoud
- Pesticides Chemistry and Toxicology Department, Faculty of Agriculture, Kafrelsheikh University, Kafrelsheikh 33516, Egypt; (A.M.); (A.D.); (M.S.A.)
| | - Aly Derbalah
- Pesticides Chemistry and Toxicology Department, Faculty of Agriculture, Kafrelsheikh University, Kafrelsheikh 33516, Egypt; (A.M.); (A.D.); (M.S.A.)
| | - Ibrahim El-Mehasseb
- Chemistry Department, Faculty of Science, Kafrelsheikh University, Kafrelsheikh 33516, Egypt;
| | - Moustafa Saad Allah
- Pesticides Chemistry and Toxicology Department, Faculty of Agriculture, Kafrelsheikh University, Kafrelsheikh 33516, Egypt; (A.M.); (A.D.); (M.S.A.)
| | - Mohamed S. Ahmed
- Department of Pathology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt;
| | - Ashraf Albrakati
- Department of Human Anatomy, College of Medicine, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia;
| | - Ehab Kotb Elmahallawy
- Department of Biomedical Sciences, University of Leon, 24004 Leon, Spain
- Department of Zoonoses, Faculty of Veterinary Medicine, Sohag University, Sohag 82524, Egypt
- Correspondence:
| |
Collapse
|
5
|
Uncertainty propagation in nuclear forensics. Appl Radiat Isot 2014; 89:58-64. [DOI: 10.1016/j.apradiso.2014.02.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 01/31/2014] [Accepted: 02/06/2014] [Indexed: 11/20/2022]
|
6
|
Suliman G, Pommé S, Marouli M, Van Ammel R, Stroh H, Jobbágy V, Paepen J, Dirican A, Bruchertseifer F, Apostolidis C, Morgenstern A. Half-lives of 221Fr, 217At, 213Bi, 213Po and 209Pb from the 225Ac decay series. Appl Radiat Isot 2013; 77:32-7. [PMID: 23511775 DOI: 10.1016/j.apradiso.2013.02.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Revised: 02/04/2013] [Accepted: 02/11/2013] [Indexed: 11/15/2022]
Abstract
The half-lives of (221)Fr, (217)At, (213)Bi, (213)Po, and (209)Pb were measured by means of an ion-implanted planar Si detector for alpha and beta particles emitted from weak (225)Ac sources or from recoil sources, which were placed in a quasi-2π counting geometry. Recoil sources were prepared by collecting atoms from an open (225)Ac source onto a glass substrate. The (221)Fr and (213)Bi half-lives were determined by following the alpha particle emission rate of recoil sources as a function of time. Similarly, the (209)Pb half-life was determined from the beta particle count rate. The shorter half-lives of (217)At and (213)Po were deduced from delayed coincidence measurements on weak (225)Ac sources using digital data acquisition in list mode. The resulting values: T1/2((221)Fr)=4.806 (6) min, T1/2((217)At)=32.8 (3)ms, T1/2((213)Bi)=45.62 (6)min, T1/2((213)Po)=3.708 (8) μs, and T1/2((209)Pb)=3.232 (5)h were in agreement only with the best literature data.
Collapse
Affiliation(s)
- G Suliman
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Marouli M, Suliman G, Pommé S, Ammel RV, Jobbágy V, Stroh H, Dikmen H, Paepen J, Dirican A, Bruchertseifer F, Apostolidis C, Morgenstern A. Decay data measurements on 213Bi using recoil atoms. Appl Radiat Isot 2013; 74:123-7. [PMID: 23416406 DOI: 10.1016/j.apradiso.2012.12.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 12/06/2012] [Accepted: 12/08/2012] [Indexed: 11/29/2022]
Abstract
In this work, (213)Bi has been separated from an open (225)Ac source by collecting recoil atoms onto a glass plate in vacuum. The activity of such recoil sources has been measured as a function of time, using an ion-implanted planar Si detector in quasi-2π geometry. From these measurements, a new half-life value of T1/2((213)Bi)=45.62 (6)min was derived. Additionally, high-resolution alpha-spectrometry measurements were performed at a solid angle of 0.4% of 4πsr, to verify the energies and emission probabilities of the α-emissions from (213)Bi. Using (225)Ac, (221)Fr, (217)At and (213)Po peaks as reference peaks, the measured (213)Bi α-peak energies at Eα,0=5878 (4)keV and Eα,1=5560 (4)keV were about 10keV higher than validated data. The relative α-particle emission probabilities of (213)Bi, Pα,0=0.9155 (11) and Pα,1=0.0845 (11), and the (213)Bi alpha branching factor, Pα=1-Pβ=2.140 (10)%, are compatible with recommended values, but have a higher accuracy.
Collapse
Affiliation(s)
- M Marouli
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Badikov SA, Chechev VP. Procedure for statistical analysis of one-parameter discrepant experimental data. Appl Radiat Isot 2012; 70:1850-2. [PMID: 22459280 DOI: 10.1016/j.apradiso.2012.02.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 02/16/2012] [Indexed: 11/18/2022]
Abstract
A new, Mandel-Paule-type procedure for statistical processing of one-parameter discrepant experimental data is described. The procedure enables one to estimate a contribution of unrecognized experimental errors into the total experimental uncertainty as well as to include it in analysis. A definition of discrepant experimental data for an arbitrary number of measurements is introduced as an accompanying result. In the case of negligible unrecognized experimental errors, the procedure simply reduces to the calculation of the weighted average and its internal uncertainty. The procedure was applied to the statistical analysis of half-life experimental data; Mean half-lives for 20 actinides were calculated and results were compared to the ENSDF and DDEP evaluations. On the whole, the calculated half-lives are consistent with the ENSDF and DDEP evaluations. However, the uncertainties calculated in this work essentially exceed the ENSDF and DDEP evaluations for discrepant experimental data. This effect can be explained by adequately taking into account unrecognized experimental errors.
Collapse
Affiliation(s)
- Sergey A Badikov
- JSC Energy & Industry Analytica, 38 A/1 2-ya Khutorskaya St., Moscow 127287, Russia.
| | | |
Collapse
|
9
|
Arinc A, Johansson LC, Gilligan CRD, Pearce AK. Standardisation of (210)Pb by Čerenkov counting. Appl Radiat Isot 2011; 69:768-72. [PMID: 21288729 DOI: 10.1016/j.apradiso.2011.01.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 12/16/2010] [Accepted: 01/04/2011] [Indexed: 10/18/2022]
Abstract
A standard of (210)Pb in solution was produced at the National Physical Laboratory by a novel technique combining Čerenkov counting with the established liquid scintillation efficiency tracing technique known as the CIEMAT/NIST method. Coincidence counting was applied in order to validate the measurements and the activity concentrations of the solution determined with each technique are shown to be in agreement. Radiochemical separation of the (210)Pb from its daughters was also necessary and the scheme for the separation is described. After performing this two-stage standardisation, the uncertainty was successfully lowered to 0.66% (k=1). This uncertainty is approximately a factor of four lower than previously achieved at NPL by the classical method of standardisation of radionuclides, i.e. coincidence counting.
Collapse
Affiliation(s)
- Arzu Arinc
- National Physical Laboratory, Hampton Road, Teddington, United Kingdom.
| | | | | | | |
Collapse
|
10
|
Van Ammel R, Paepen J, Pommé S, Sibbens G. Measurement of the (54)Mn half-life. Appl Radiat Isot 2010; 68:2387-92. [PMID: 20580237 DOI: 10.1016/j.apradiso.2010.06.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Revised: 06/02/2010] [Accepted: 06/04/2010] [Indexed: 11/28/2022]
Abstract
The half-life of (54)Mn was measured by following the decay of sources from a radiochemically pure solution using three different measuring systems: an ionisation chamber, a high-purity germanium (HPGe) detector and two 7.5 cm (diameter) × 7.5 cm (height) NaI(Tl) scintillation detectors in opposite position. The measurements were performed over a period of 3 years, i.e. about 3.5 half-lives of (54)Mn. The resulting half-life values and detailed uncertainty budgets are presented for the three measuring systems. The half-life obtained with the ionisation chamber, 312.32 (9) days, is consistent with but more precise than the ones obtained with the HPGe detector, 311.9 (5) days and the NaI(Tl) detectors, 311.9 (6) days, respectively. Our final half-life value of 312.32 (9) days is rather consistent with the currently recommended values of 312.29 (26) (IAEA, 2007) and 312.13 (3) days (Helmer and Schönfeld, 2004), even though the uncertainty of the latter may be underestimated. From a partially weighted mean (Pommé and Spasova, 2008) of selected experimental values published after 1970, a new best estimate of T(1/2)((54)Mn)=312.20 (8) days was calculated.
Collapse
Affiliation(s)
- R Van Ammel
- European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel, Belgium.
| | | | | | | |
Collapse
|
11
|
Abstract
I report on the operation and characterization of a new ionization chamber system, "AUTOIC", featuring a commercial digital electrometer and a commercial robotic sample changer. The relative accuracy of the electrometer was improved significantly beyond the manufacturer's specifications through an in-house calibration of the various ranges, applied via software. The measurement precision and repeatability of the system have been determined by measuring multiple samples of the same radionuclide over the span of two or three years. The linearity of the system was examined by following the decay of (99m)Tc, (99)Mo and (133)Xe sources for up to 19 half-lives and determining half-life values. All of these values agree with the accepted literature values, within their combined uncertainties.
Collapse
Affiliation(s)
- R Fitzgerald
- Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
| |
Collapse
|
12
|
Paul M, Valenta A, Ahmad I, Berkovits D, Bordeanu C, Ghelberg S, Hashimoto Y, Hershkowitz A, Jiang S, Nakanishi T, Sakamoto K. An upper limit to interstellar 244Pu abundance as deduced from radiochemical search in deep-sea sediment: An account. J Radioanal Nucl Chem 2007. [DOI: 10.1007/s10967-007-0508-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|