Bioremediation is a sustainable Biological strategy, to remove hazardous substances from the contaminated areas by living organisms. Shewanella azerbaijanica is introduced as a highly potent bacterium in metal bioremediation. The current study has applied a comparison of functional bioremediation processes in recombinant (RSh) and native (NSh) Shewanella azerbaijanica bacteria. The RSh maintained the cloned mtrC gene as a principal gene in the EET (Extracellular Electron Transfer) pathway. The uranium bioremediation procedure evaluated through cell counting and ICP analysis in RSh and NSh, Despite, fewer viable cells, RSh showed 21 % higher uranium removal efficiency than NSh, likely due to the metabolic load of plasmid maintenance and recombinant protein expression enhancing electron transfer for uranium reduction. The uranium reduction process was confirmed through XRD and UV–Vis spectroscopy in RSh. Thereupon, the recombinant bacteria have been proposed as an efficient genetically manipulated strain in future metals bioremediation studies.
{"title":"Functional promotion of uranium bioremediation in recombinant Shewanella azerbaijanica","authors":"Elham Rastkhah , Parvaneh Maghami , Razieh Ghasemi , Faezeh Fatemi","doi":"10.1016/j.apradiso.2025.112415","DOIUrl":"10.1016/j.apradiso.2025.112415","url":null,"abstract":"<div><div>Bioremediation is a sustainable Biological strategy, to remove hazardous substances from the contaminated areas by living organisms. <em>Shewanella azerbaijanica</em> is introduced as a highly potent bacterium in metal bioremediation. The current study has applied a comparison of functional bioremediation processes in recombinant (RSh) and native (NSh) <em>Shewanella azerbaijanica</em> bacteria. The RSh maintained the cloned <em>mtr</em>C gene as a principal gene in the EET (Extracellular Electron Transfer) pathway. The uranium bioremediation procedure evaluated through cell counting and ICP analysis in RSh and NSh, Despite, fewer viable cells, RSh showed 21 % higher uranium removal efficiency than NSh, likely due to the metabolic load of plasmid maintenance and recombinant protein expression enhancing electron transfer for uranium reduction. The uranium reduction process was confirmed through XRD and UV–Vis spectroscopy in RSh. Thereupon, the recombinant bacteria have been proposed as an efficient genetically manipulated strain in future metals bioremediation studies.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112415"},"PeriodicalIF":1.8,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145916257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-05DOI: 10.1016/j.apradiso.2025.112408
Zbigniew Tymiński, Paweł Saganowski, Małgorzata Żółtowska, Izabela Cieszykowska, Ewa Kołakowska, Justyna Marganiec-Gałązka, Natalia Lisowska, Aleksander Kamiński, Marek Czudek, Daniel Cacko, Ryszard Broda
Scandium-47 can be produced indirectly via the 46Ca(n,γ)47Ca→47Sc nuclear reaction by neutron irradiation of calcium targets, either natural or, preferably, enriched in calcium-46. Two target materials differing in the enrichment in calcium-46 and the elemental and isotopic composition were irradiated in the MARIA research reactor. Radioactive concentration of scandium-47 and the radionuclidic purity of the solution obtained after irradiated target dissolution were assessed by gamma-spectrometry using a high-purity germanium (HPGe) detector in the Laboratory of Radioactivity Standards in the Radioisotope Centre POLATOM, NCBJ. The radioactive concentration of scandium-47 was in the range of 0.20–1.48 GBq/mL, and the content of calcium-47 was determined at the level ranging from 0.006 % to 0.055 % of scandium-47 in the final products. The profile of radionuclide impurities and their minimum detectable activities are discussed.
{"title":"Gamma-ray spectrometry measurements for quality assessment of scandium-47 produced by neutron irradiation of calcium-46","authors":"Zbigniew Tymiński, Paweł Saganowski, Małgorzata Żółtowska, Izabela Cieszykowska, Ewa Kołakowska, Justyna Marganiec-Gałązka, Natalia Lisowska, Aleksander Kamiński, Marek Czudek, Daniel Cacko, Ryszard Broda","doi":"10.1016/j.apradiso.2025.112408","DOIUrl":"10.1016/j.apradiso.2025.112408","url":null,"abstract":"<div><div>Scandium-47 can be produced indirectly via the <sup>46</sup>Ca(n,γ)<sup>47</sup>Ca→<sup>47</sup>Sc nuclear reaction by neutron irradiation of calcium targets, either natural or, preferably, enriched in calcium-46. Two target materials differing in the enrichment in calcium-46 and the elemental and isotopic composition were irradiated in the MARIA research reactor. Radioactive concentration of scandium-47 and the radionuclidic purity of the solution obtained after irradiated target dissolution were assessed by gamma-spectrometry using a high-purity germanium (HPGe) detector in the Laboratory of Radioactivity Standards in the Radioisotope Centre POLATOM, NCBJ. The radioactive concentration of scandium-47 was in the range of 0.20–1.48 GBq/mL, and the content of calcium-47 was determined at the level ranging from 0.006 % to 0.055 % of scandium-47 in the final products. The profile of radionuclide impurities and their minimum detectable activities are discussed.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112408"},"PeriodicalIF":1.8,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145910328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-03DOI: 10.1016/j.apradiso.2026.112417
Shah Azharul Islam , Md Kamruzzaman , Fahim Sabab Siddique , Shahadat Hossain , Md Al-Mamun , A.K.M. Mizanur Rahman
This study evaluates the thermoluminescence (TL) dosimetry potential of Ce-doped lithium zinc borate (LZB) synthesized via the solid-state reaction method. The crystalline phase integrity and functional groups were verified using XRD and FTIR, while SEM-EDS confirmed the homogenous distribution of Ce-activators. Vibrating Sample Magnetometer (VSM) was used for magnetic characterisation, which demonstrated the emergence of superparamagnetic behaviour after doping. Samples were subjected to 6 MeV electron and 6 MV X-ray irradiation (0.5–8 Gy) to evaluate dose-response linearity using clinical LINAC. Results indicate that LZB:Ce (1 %) significantly enhances dose-response linearity and sensitivity compared to the undoped host. Kinetic analysis was performed using Chen's peak-shape method, where a calculated geometric factor (0.50) confirmed general-order kinetics and significant charge carrier re-trapping. The extracted activation energies Ea ranged at ∼0.72/0.92 eV for shallow trap and ∼4.99/5.22 eV for deep trap due to defect centre, calculated by Computerized Glow Curve Deconvolution (CGCD). Despite a relative reduction in peak intensity, the material exhibited superior thermal stability and improved fading over 50 days, positioning Ce-doped LZB as a robust and technically viable candidate for dosimetry application and need long term study for more feasibility as an alternative.
{"title":"Precision radiation measurement: LiZnBO3:Ce phosphor thermoluminescent properties","authors":"Shah Azharul Islam , Md Kamruzzaman , Fahim Sabab Siddique , Shahadat Hossain , Md Al-Mamun , A.K.M. Mizanur Rahman","doi":"10.1016/j.apradiso.2026.112417","DOIUrl":"10.1016/j.apradiso.2026.112417","url":null,"abstract":"<div><div>This study evaluates the thermoluminescence (TL) dosimetry potential of Ce-doped lithium zinc borate (LZB) synthesized via the solid-state reaction method. The crystalline phase integrity and functional groups were verified using XRD and FTIR, while SEM-EDS confirmed the homogenous distribution of Ce-activators. Vibrating Sample Magnetometer (VSM) was used for magnetic characterisation, which demonstrated the emergence of superparamagnetic behaviour after doping. Samples were subjected to 6 MeV electron and 6 MV X-ray irradiation (0.5–8 Gy) to evaluate dose-response linearity using clinical LINAC. Results indicate that LZB:Ce (1 %) significantly enhances dose-response linearity and sensitivity compared to the undoped host. Kinetic analysis was performed using Chen's peak-shape method, where a calculated geometric factor (0.50) confirmed general-order kinetics and significant charge carrier re-trapping. The extracted activation energies E<sub>a</sub> ranged at ∼0.72/0.92 eV for shallow trap and ∼4.99/5.22 eV for deep trap due to defect centre, calculated by Computerized Glow Curve Deconvolution (CGCD). Despite a relative reduction in peak intensity, the material exhibited superior thermal stability and improved fading over 50 days, positioning Ce-doped LZB as a robust and technically viable candidate for dosimetry application and need long term study for more feasibility as an alternative.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112417"},"PeriodicalIF":1.8,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145916266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hybrid extractive scintillating resins (HESR) were developed for uptake and detection of aqueous plutonium (Pu) in groundwater and surface water. These resins consist of titanium dioxide (TiO2), which is responsible for Pu uptake, embedded within a scintillating polymer. The scintillating resin emits light when excited by alpha radiation from plutonium, which can be detected with a liquid scintillation counter without a scintillation cocktail. The physical characteristics of HESR were evaluated using thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Batch uptake measurements for aqueous plutonium-238 (+5 oxidation state) were performed using resin beads with diameters of 106–212 μm. For the HESR resin containing 57 wt% TiO2, HESR (57), with a contact time of 1440 min, the Pu uptake was 88.9 ± 4.9 Bq/g with a conditional KD of 860 mL/g. The corresponding plutonium detection efficiency was 96 %. HESR (57) displayed a linear Pu detection response, and a minimum detectable concentration of 0.38 Bq/L Pu(V) was calculated for a batch uptake experiment.
{"title":"Quantifying aqueous plutonium using hybrid extractive scintillating resins","authors":"T.A. DeVol , V.N. Bliznyuk , B.A. Powell , S.M. Husson","doi":"10.1016/j.apradiso.2025.112414","DOIUrl":"10.1016/j.apradiso.2025.112414","url":null,"abstract":"<div><div>Hybrid extractive scintillating resins (HESR) were developed for uptake and detection of aqueous plutonium (Pu) in groundwater and surface water. These resins consist of titanium dioxide (TiO<sub>2</sub>), which is responsible for Pu uptake, embedded within a scintillating polymer. The scintillating resin emits light when excited by alpha radiation from plutonium, which can be detected with a liquid scintillation counter without a scintillation cocktail. The physical characteristics of HESR were evaluated using thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Batch uptake measurements for aqueous plutonium-238 (+5 oxidation state) were performed using resin beads with diameters of 106–212 μm. For the HESR resin containing 57 wt% TiO<sub>2</sub>, HESR (57), with a contact time of 1440 min, the Pu uptake was 88.9 ± 4.9 Bq/g with a conditional K<sub>D</sub> of 860 mL/g. The corresponding plutonium detection efficiency was 96 %. HESR (57) displayed a linear Pu detection response, and a minimum detectable concentration of 0.38 Bq/L Pu(V) was calculated for a batch uptake experiment.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112414"},"PeriodicalIF":1.8,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-31DOI: 10.1016/j.apradiso.2025.112409
Konstantinos Karafasoulis , Aristotelis Kyriakis
The detection of weak radioactive sources in fluctuating background environments is a critical task for nuclear security, environmental monitoring, and emergency response. Compact gamma-ray detectors, such as small-volume CdZnTe (CZT) crystals, are well suited for portable and drone-mounted applications, but their limited active volume yields low-count spectra over short acquisition times. While most radiation detection systems can acquire spectra over short integration times, the key challenge is whether such brief acquisitions from compact detectors provide sufficient statistical information for reliable anomaly detection. In this work, we present an anomaly detection approach based on a convolutional autoencoder trained exclusively on background gamma spectra. The detector used is a 0.5cm CZT device that records 1024-channel spectra in operational low-count regime from short acquisitions. To provide probabilistic decision-making, Bayesian inference is applied to map reconstruction errors to anomaly probabilities. The method is evaluated on real spectra containing background alone and source-plus-background combinations for , , and at varying source–detector distances. Results show that the autoencoder detects anomalies at source–detector distances where total counts overlap strongly with background and conventional Currie-type thresholds fail. Compared to the total counts method, the autoencoder achieves higher sensitivity, detecting weak anomalies at distances up to 50 cm. These findings demonstrate that deep-learning methods can enhance the performance of compact detectors, enabling practical, mobile radiation monitoring systems with improved sensitivity in real-world operational scenarios.
{"title":"Anomaly detection in gamma-ray spectra using autoencoders with small form factor CZT detectors","authors":"Konstantinos Karafasoulis , Aristotelis Kyriakis","doi":"10.1016/j.apradiso.2025.112409","DOIUrl":"10.1016/j.apradiso.2025.112409","url":null,"abstract":"<div><div>The detection of weak radioactive sources in fluctuating background environments is a critical task for nuclear security, environmental monitoring, and emergency response. Compact gamma-ray detectors, such as small-volume CdZnTe (CZT) crystals, are well suited for portable and drone-mounted applications, but their limited active volume yields low-count spectra over short acquisition times. While most radiation detection systems can acquire spectra over short integration times, the key challenge is whether such brief acquisitions from compact detectors provide sufficient statistical information for reliable anomaly detection. In this work, we present an anomaly detection approach based on a convolutional autoencoder trained exclusively on background gamma spectra. The detector used is a 0.5cm<span><math><msup><mrow></mrow><mrow><mn>3</mn></mrow></msup></math></span> CZT device that records 1024-channel spectra in operational low-count regime from short acquisitions. To provide probabilistic decision-making, Bayesian inference is applied to map reconstruction errors to anomaly probabilities. The method is evaluated on real spectra containing background alone and source-plus-background combinations for <span><math><mrow><msup><mrow></mrow><mrow><mn>137</mn></mrow></msup><mi>C</mi><mi>s</mi></mrow></math></span>, <span><math><mrow><msup><mrow></mrow><mrow><mn>241</mn></mrow></msup><mi>A</mi><mi>m</mi></mrow></math></span>, and <span><math><mrow><msup><mrow></mrow><mrow><mn>152</mn></mrow></msup><mi>E</mi><mi>u</mi></mrow></math></span> at varying source–detector distances. Results show that the autoencoder detects anomalies at source–detector distances where total counts overlap strongly with background and conventional Currie-type thresholds fail. Compared to the total counts method, the autoencoder achieves higher sensitivity, detecting weak <span><math><mrow><msup><mrow></mrow><mrow><mn>137</mn></mrow></msup><mi>C</mi><mi>s</mi></mrow></math></span> anomalies at distances up to 50 cm. These findings demonstrate that deep-learning methods can enhance the performance of compact detectors, enabling practical, mobile radiation monitoring systems with improved sensitivity in real-world operational scenarios.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112409"},"PeriodicalIF":1.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-31DOI: 10.1016/j.apradiso.2025.112411
E. Uyar , M.H. Bölükdemir
HPGe detector characterization is the determination of the geometric parameters of the detector as precisely as possible in gamma spectrometric studies. This is accomplished by a procedure that combines efficiency measurements obtained from experimental and Monte Carlo simulations. One way to perform a correct characterization of the detector is to use X-ray equipment to produce images of the detector components. Optimal dimensions were determined from the values given by the manufacturer and the values obtained from the X-ray image and used in the Monte Carlo simulation. The characterization of the carbon fiber windowed HPGe detector was performed using the experimental efficiency calculations calculated at 10 and 15 cm distances with point sources with energies between 59.5 and 1836.1 keV and the efficiency values obtained from the Monte Carlo method. The results of the study showed that the discrepancy between the simulated efficiency values and the experimental efficiency values decreased from 6.5 % to 18.4 % with the manufacturer's data to 0 %–2.1 % with the optimal values obtained after characterization. This agreement with the determined optimal values at two different distances and 7 different energies shows that the germanium dead layer thickness, which is a dynamic parameter of the detector, has also been determined correctly.
{"title":"Characterization of carbon fiber window HPGe detector using Computed Tomography","authors":"E. Uyar , M.H. Bölükdemir","doi":"10.1016/j.apradiso.2025.112411","DOIUrl":"10.1016/j.apradiso.2025.112411","url":null,"abstract":"<div><div>HPGe detector characterization is the determination of the geometric parameters of the detector as precisely as possible in gamma spectrometric studies. This is accomplished by a procedure that combines efficiency measurements obtained from experimental and Monte Carlo simulations. One way to perform a correct characterization of the detector is to use X-ray equipment to produce images of the detector components. Optimal dimensions were determined from the values given by the manufacturer and the values obtained from the X-ray image and used in the Monte Carlo simulation. The characterization of the carbon fiber windowed HPGe detector was performed using the experimental efficiency calculations calculated at 10 and 15 cm distances with point sources with energies between 59.5 and 1836.1 keV and the efficiency values obtained from the Monte Carlo method. The results of the study showed that the discrepancy between the simulated efficiency values and the experimental efficiency values decreased from 6.5 % to 18.4 % with the manufacturer's data to 0 %–2.1 % with the optimal values obtained after characterization. This agreement with the determined optimal values at two different distances and 7 different energies shows that the germanium dead layer thickness, which is a dynamic parameter of the detector, has also been determined correctly.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112411"},"PeriodicalIF":1.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-31DOI: 10.1016/j.apradiso.2025.112416
Miroslaw Janik, Jun Ichinose, Kotaro Nagatsu, Satoshi Kodaira
Efficient mitigation of 222Rn releases is essential for the safe handling of 226Ra and related -emitters used in targeted radiotherapy. We evaluated a suite of sorbent materials, including silver-exchanged zeolites and activated carbon, under controlled laboratory conditions. Breakthrough experiments were conducted at defined dew points, and 222Rn retention was quantified using retention time (), adsorption coefficient (), and radon retention capacity (). Across all materials, values decreased systematically with increasing dew point, confirming the strong competitive effect of water vapor. Silver-exchanged Ag-ETS-10 zeolite exhibited the highest initial performance ( up to 120 m3 /kg at low humidity), whereas activated carbon and Ag-MOR-2 showed lower but more humidity-tolerant behavior. Regeneration studies demonstrated that several Ag-zeolites retained a substantial fraction of their capacity after reuse. These findings highlight both the potential and the limitations of silver-based zeolites, particularly Ag-ETS-10, and underscore the importance of humidity control and regeneration protocols in the design of radon traps for isotope production facilities.
有效减缓222Rn的释放对于安全处理靶向放疗中使用的226Ra和相关α-发射器至关重要。我们评估了一套吸附材料，包括银交换沸石和活性炭，在受控的实验室条件下。在确定的露点处进行突破实验，用滞留时间（RT）、吸附系数(K)和氡滞留量（RRC）对222Rn的滞留量进行量化。在所有材料中，随着露点的增加，K值系统地下降，证实了水蒸气的强烈竞争效应。银交换的Ag-ETS-10分子筛表现出最高的初始性能（在低湿度下K高达~ 120m3/kg），而活性炭和ag - or -2表现出较低但更耐湿的行为。再生研究表明，一些银沸石在重复使用后仍保留了相当一部分容量。这些发现突出了银基沸石的潜力和局限性，特别是Ag-ETS-10，并强调了湿度控制和再生方案在同位素生产设施氡捕集器设计中的重要性。
{"title":"Humidity-dependent radon retention in zeolite and non-zeolite sorbents for 225Ac production facilities","authors":"Miroslaw Janik, Jun Ichinose, Kotaro Nagatsu, Satoshi Kodaira","doi":"10.1016/j.apradiso.2025.112416","DOIUrl":"10.1016/j.apradiso.2025.112416","url":null,"abstract":"<div><div>Efficient mitigation of <sup>222</sup>Rn releases is essential for the safe handling of <sup>226</sup>Ra and related <span><math><mi>α</mi></math></span>-emitters used in targeted radiotherapy. We evaluated a suite of sorbent materials, including silver-exchanged zeolites and activated carbon, under controlled laboratory conditions. Breakthrough experiments were conducted at defined dew points, and <sup>222</sup>Rn retention was quantified using retention time (<span><math><mrow><mi>R</mi><mi>T</mi></mrow></math></span>), adsorption coefficient (<span><math><mi>K</mi></math></span>), and radon retention capacity (<span><math><mrow><mi>R</mi><mi>R</mi><mi>C</mi></mrow></math></span>). Across all materials, <span><math><mi>K</mi></math></span> values decreased systematically with increasing dew point, confirming the strong competitive effect of water vapor. Silver-exchanged Ag-ETS-10 zeolite exhibited the highest initial performance (<span><math><mi>K</mi></math></span> up to <span><math><mo>∼</mo></math></span>120<!--> <!-->m<sup>3</sup> <!-->/kg at low humidity), whereas activated carbon and Ag-MOR-2 showed lower but more humidity-tolerant behavior. Regeneration studies demonstrated that several Ag-zeolites retained a substantial fraction of their capacity after reuse. These findings highlight both the potential and the limitations of silver-based zeolites, particularly Ag-ETS-10, and underscore the importance of humidity control and regeneration protocols in the design of radon traps for isotope production facilities.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112416"},"PeriodicalIF":1.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145916454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study examined the radiation shielding efficacy of the PbO2-BaO-CaO-B2O3-Y2O3-Sm2O3 glass system. Four glass composites were synthesized, designated as YSm0.25 (10 % PbO2, 0.25 % Y2O3, 0.25 % Sm2O3 and 59.5 % B2O3), YSm0.5 (13 % PbO2, 0.5 % Y2O3, 0.5 % Sm2O3 and 56 % B2O3), YSm0.75 (16 % PbO2, 0.75 % Y2O3, 0.75 % Sm2O3 and 52.5 % B2O3), and YSm1 (19 % PbO2, 1 % Y2O3, 1 % Sm2O3 and 49 % B2O3). The gamma-ray attenuation properties were evaluated experimentally utilizing a narrow-beam transmission setup with standard sealed isotopes 133Ba, 137Cs, 22Na and 60Co (356–1332 keV) with a 2" × 2″ NaI(Tl) scintillation detector. The experimental mass attenuation coefficients (GMAC) were compared with theoretical estimates of these parameters from Phy-X/PSD and good agreement of the experimental GMAC was evident with deviations of <6 %. The results indicated the higher concentrations of PbO2, Y2O3 and Sm2O3 increased the density which improved the overall shielding efficiency. The GMAC decreased as the photon energy increased, which aligned with the known energy dependence of gamma interactions. For the most shielded glass composition (YSm1), the half-value layer (HVL) at 662 keV was 1.88 cm which was considerably lower for the other samples. The radiation protection efficiency (GRPE) values at a thickness of 1 cm decreased with energy from 42.62 to 48.78 % at 356 keV from samples and 16.64–20.52 % at 1332 keV. YSm1 displayed the highest attenuation capability, the lower mean free path, and transmission factor at all energies investigated.
{"title":"Impact of Y2O3 and Sm2O3 doping on the radiation shielding properties of lead-borate glasses","authors":"M.I. Sayyed , Manjunatha , A.S. Bennal , Mohamed.Y. Hanfi , Venkatesh.K. Bhovi , Shams.A.M. Issa","doi":"10.1016/j.apradiso.2025.112407","DOIUrl":"10.1016/j.apradiso.2025.112407","url":null,"abstract":"<div><div>This study examined the radiation shielding efficacy of the PbO<sub>2</sub>-BaO-CaO-B<sub>2</sub>O<sub>3</sub>-Y<sub>2</sub>O<sub>3</sub>-Sm<sub>2</sub>O<sub>3</sub> glass system. Four glass composites were synthesized, designated as YSm0.25 (10 % PbO<sub>2</sub>, 0.25 % Y<sub>2</sub>O<sub>3</sub>, 0.25 % Sm<sub>2</sub>O<sub>3</sub> and 59.5 % B<sub>2</sub>O<sub>3</sub>), YSm0.5 (13 % PbO<sub>2</sub>, 0.5 % Y<sub>2</sub>O<sub>3</sub>, 0.5 % Sm<sub>2</sub>O<sub>3</sub> and 56 % B<sub>2</sub>O<sub>3</sub>), YSm0.75 (16 % PbO<sub>2</sub>, 0.75 % Y<sub>2</sub>O<sub>3</sub>, 0.75 % Sm<sub>2</sub>O<sub>3</sub> and 52.5 % B<sub>2</sub>O<sub>3</sub>), and YSm1 (19 % PbO<sub>2</sub>, 1 % Y<sub>2</sub>O<sub>3</sub>, 1 % Sm<sub>2</sub>O<sub>3</sub> and 49 % B<sub>2</sub>O<sub>3</sub>). The gamma-ray attenuation properties were evaluated experimentally utilizing a narrow-beam transmission setup with standard sealed isotopes <sup>133</sup>Ba, <sup>137</sup>Cs, <sup>22</sup>Na and <sup>60</sup>Co (356–1332 keV) with a 2\" × 2″ NaI(Tl) scintillation detector. The experimental mass attenuation coefficients (G<sub>MAC</sub>) were compared with theoretical estimates of these parameters from Phy-X/PSD and good agreement of the experimental G<sub>MAC</sub> was evident with deviations of <6 %. The results indicated the higher concentrations of PbO<sub>2</sub>, Y<sub>2</sub>O<sub>3</sub> and Sm<sub>2</sub>O<sub>3</sub> increased the density which improved the overall shielding efficiency. The G<sub>MAC</sub> decreased as the photon energy increased, which aligned with the known energy dependence of gamma interactions. For the most shielded glass composition (YSm1), the half-value layer (HVL) at 662 keV was 1.88 cm which was considerably lower for the other samples. The radiation protection efficiency (G<sub>RPE</sub>) values at a thickness of 1 cm decreased with energy from 42.62 to 48.78 % at 356 keV from samples and 16.64–20.52 % at 1332 keV. YSm1 displayed the highest attenuation capability, the lower mean free path, and transmission factor at all energies investigated.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112407"},"PeriodicalIF":1.8,"publicationDate":"2025-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-30DOI: 10.1016/j.apradiso.2025.112413
H. Ramebäck, K. Norlin, M. Östman
Environmental monitoring of e.g. radionuclides are important in order to establish a baseline of radionuclides present in the environment, e.g. in order to detect increases in activites. Often low activities are present which require long measurement times. This work presents improvements with respect to reducing instrument time required when measuring to a pre-determined MDA (Minimum Detectable Activity). The method studied, involved the separation of 137Cs in tap water samples using AMP-PAN (ammonium molybdophosphate in polyacetonitrile) combined with IDGS (isotope dilution gamma spectrometry). The results show that significantly lower instrument times can be used when measuring to a pre-determined MDA (considered fit-for-purpose), if the same amount of sample can be measured in a more efficient geometry. Moreover, using more sample volume will also decrease the instrument time significantly. Measurement times will, for increased efficiencies, approximately be shortened by a factor equal to the square of the ratio between the efficiencies. Likewise, instrument time will approximately be reduced by a factor equal to the square of the ratios of sample volumes when sample volume is increased. The same relationship is valid for chemical yield, emphasising the importance of high chemical yields. When implementing AMP-separation of 137Cs and doubling the sample volume compared to the original laboratory method (evaporation), the instrument time needed to reach the target MDA (0.60 mBq/L) was reduced by a factor of about eight. Apart from a much shorter measurement time, the time for sample preparation was shortened from a few days to about 2 h.
{"title":"The effect of increased sample volume and peak efficiency on instrument time when measuring to a pre-determined MDA: Applied to AMP-separation of 137Cs in tap-water samples","authors":"H. Ramebäck, K. Norlin, M. Östman","doi":"10.1016/j.apradiso.2025.112413","DOIUrl":"10.1016/j.apradiso.2025.112413","url":null,"abstract":"<div><div>Environmental monitoring of <em>e.g.</em> radionuclides are important in order to establish a baseline of radionuclides present in the environment, <em>e.g.</em> in order to detect increases in activites. Often low activities are present which require long measurement times. This work presents improvements with respect to reducing instrument time required when measuring to a pre-determined MDA (Minimum Detectable Activity). The method studied, involved the separation of <sup>137</sup>Cs in tap water samples using AMP-PAN (ammonium molybdophosphate in polyacetonitrile) combined with IDGS (isotope dilution gamma spectrometry). The results show that significantly lower instrument times can be used when measuring to a pre-determined MDA (considered fit-for-purpose), if the same amount of sample can be measured in a more efficient geometry. Moreover, using more sample volume will also decrease the instrument time significantly. Measurement times will, for increased efficiencies, approximately be shortened by a factor equal to the square of the ratio between the efficiencies. Likewise, instrument time will approximately be reduced by a factor equal to the square of the ratios of sample volumes when sample volume is increased. The same relationship is valid for chemical yield, emphasising the importance of high chemical yields. When implementing AMP-separation of <sup>137</sup>Cs and doubling the sample volume compared to the original laboratory method (evaporation), the instrument time needed to reach the target MDA (0.60 mBq/L) was reduced by a factor of about eight. Apart from a much shorter measurement time, the time for sample preparation was shortened from a few days to about 2 h.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112413"},"PeriodicalIF":1.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-30DOI: 10.1016/j.apradiso.2025.112412
Linde Pollet , Mikael Hult , Mirela Vasile , Gerd Marissens , Heiko Stroh , Sonja Schreurs , Wouter Schroeyers
Geothermal energy originates from the heat stored within the Earth's core. Thermal water from geological reservoirs is extracted to the surface to generate electricity or heat buildings and greenhouses. This thermal water contains various dissolved solids that can deposit, precipitate, and form scales in the installations as the water is brought to the surface. The dissolved solids contain primordial radionuclides. Workers are exposed to these radionuclides while maintaining and cleaning geothermal plants.
This study complements the limited research available on naturally occurring radionuclides in geothermal installations by examining their presence in various facilities across the Netherlands. Sludge and scale samples were provided from five different surface installations. The samples were analysed using radiometric methods (alpha-particle and gamma-ray spectrometry) and a non-radiometric method (energy dispersive X-ray fluorescence, EDXRF). EDXRF identified several hazardous elements, such as Lead, Arsenic, Chromium, and Thallium. In the scales, radiometric analysis detected three main radionuclides: 228Th, 210Pb, and 210Po. Furthermore, for both scales and sludges, a notable disruption in the equilibrium was observed in parts of the natural decay chains 232Th-228Ra-228Th and 226Ra-210Pb-210Po, complicating the correct assessment of the massic activity of the radionuclides and the appropriate disposal of the materials. These findings highlight the importance of mapping Naturally Occurring Radioactive Materials (NORM) during geothermal plant maintenance and accurately assessing their massic activity.
{"title":"A radiometric and elemental characterisation of sludge and scales found in Dutch geothermal plants","authors":"Linde Pollet , Mikael Hult , Mirela Vasile , Gerd Marissens , Heiko Stroh , Sonja Schreurs , Wouter Schroeyers","doi":"10.1016/j.apradiso.2025.112412","DOIUrl":"10.1016/j.apradiso.2025.112412","url":null,"abstract":"<div><div>Geothermal energy originates from the heat stored within the Earth's core. Thermal water from geological reservoirs is extracted to the surface to generate electricity or heat buildings and greenhouses. This thermal water contains various dissolved solids that can deposit, precipitate, and form scales in the installations as the water is brought to the surface. The dissolved solids contain primordial radionuclides. Workers are exposed to these radionuclides while maintaining and cleaning geothermal plants.</div><div>This study complements the limited research available on naturally occurring radionuclides in geothermal installations by examining their presence in various facilities across the Netherlands. Sludge and scale samples were provided from five different surface installations. The samples were analysed using radiometric methods (alpha-particle and gamma-ray spectrometry) and a non-radiometric method (energy dispersive X-ray fluorescence, EDXRF). EDXRF identified several hazardous elements, such as Lead, Arsenic, Chromium, and Thallium. In the scales, radiometric analysis detected three main radionuclides: <sup>228</sup>Th, <sup>210</sup>Pb, and <sup>210</sup>Po. Furthermore, for both scales and sludges, a notable disruption in the equilibrium was observed in parts of the natural decay chains <sup>232</sup>Th-<sup>228</sup>Ra-<sup>228</sup>Th and <sup>226</sup>Ra-<sup>210</sup>Pb-<sup>210</sup>Po, complicating the correct assessment of the massic activity of the radionuclides and the appropriate disposal of the materials. These findings highlight the importance of mapping Naturally Occurring Radioactive Materials (NORM) during geothermal plant maintenance and accurately assessing their massic activity.</div></div>","PeriodicalId":8096,"journal":{"name":"Applied Radiation and Isotopes","volume":"229 ","pages":"Article 112412"},"PeriodicalIF":1.8,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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