G. Yoshida, H. Matsumura, Hajime Nakamura, A. Toyoda, K. Masumoto, T. Miura, K. Sasa, T. Moriguchi
To establish a systematic guideline for accelerator decommissioning, as a case study, beamline activation of 12 MeV-proton electrostatic accelerator was investigated employing a survey meter and g -ray spectrometers. Beam loss points where reflected as high dose-rate area were identified, and generated nuclides and their activities were determined. Almost beamline components are made from stainless steel and 52 Mn and 56 Co were detected as principal induced activities. It was found that the 56 Co activity significantly contribute to the dose rate value denoted on the survey meter. From the beam operation history and the monitor currents of Faraday-cups, we revealed the beam loss on a certain point significantly reflects the 52 Mn activity on there. Induced activities of 52 Mn and 56 Co on the certain point of the beamline could be reproduced by the contact dose-rate on that point.
{"title":"Survey Methodology for the Activation of Beamline Components in an Electrostatic Proton Accelerator","authors":"G. Yoshida, H. Matsumura, Hajime Nakamura, A. Toyoda, K. Masumoto, T. Miura, K. Sasa, T. Moriguchi","doi":"10.12950/RSM.200813","DOIUrl":"https://doi.org/10.12950/RSM.200813","url":null,"abstract":"To establish a systematic guideline for accelerator decommissioning, as a case study, beamline activation of 12 MeV-proton electrostatic accelerator was investigated employing a survey meter and g -ray spectrometers. Beam loss points where reflected as high dose-rate area were identified, and generated nuclides and their activities were determined. Almost beamline components are made from stainless steel and 52 Mn and 56 Co were detected as principal induced activities. It was found that the 56 Co activity significantly contribute to the dose rate value denoted on the survey meter. From the beam operation history and the monitor currents of Faraday-cups, we revealed the beam loss on a certain point significantly reflects the 52 Mn activity on there. Induced activities of 52 Mn and 56 Co on the certain point of the beamline could be reproduced by the contact dose-rate on that point.","PeriodicalId":350737,"journal":{"name":"Radiation Safety Management","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116402746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Yamamura, K. Shirasaki, H. Kikunaga, Kojiro Nagata, Zijian Zhang, K. Washiyama, A. Toyoshima, T. Yoshimura, A. Shinohara
1) Laboratory of Alpha-ray Emitters, Institute for Materials Research, Tohoku University, Miyagi 980-8577, Japan 2) Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka 590-0494, Japan 3) Research Center for Electron Photon Science, Tohoku University, Miyagi 982-0826, Japan 4) Radioisotope Research Center, Institute for Radiation Sciences, Osaka University, Osaka 565-0871, Japan 5) Department of Chemistry, Graduate School of Science, Osaka University, Osaka 560-0043, Japan 6) Advanced Clinical Research Center, Fukushima Medical University, Fukushima 960-1295, Japan 7) Division of Science, Institute for Radiation Sciences, Osaka University, Osaka 560-0043, Japan
{"title":"Transfer Rates of 225Ac to Exhaust Air, Surface, and Waste Water under Chemical Operations","authors":"T. Yamamura, K. Shirasaki, H. Kikunaga, Kojiro Nagata, Zijian Zhang, K. Washiyama, A. Toyoshima, T. Yoshimura, A. Shinohara","doi":"10.12950/rsm.191219","DOIUrl":"https://doi.org/10.12950/rsm.191219","url":null,"abstract":"1) Laboratory of Alpha-ray Emitters, Institute for Materials Research, Tohoku University, Miyagi 980-8577, Japan 2) Institute for Integrated Radiation and Nuclear Science, Kyoto University, Osaka 590-0494, Japan 3) Research Center for Electron Photon Science, Tohoku University, Miyagi 982-0826, Japan 4) Radioisotope Research Center, Institute for Radiation Sciences, Osaka University, Osaka 565-0871, Japan 5) Department of Chemistry, Graduate School of Science, Osaka University, Osaka 560-0043, Japan 6) Advanced Clinical Research Center, Fukushima Medical University, Fukushima 960-1295, Japan 7) Division of Science, Institute for Radiation Sciences, Osaka University, Osaka 560-0043, Japan","PeriodicalId":350737,"journal":{"name":"Radiation Safety Management","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124160015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Various materials containing the natural radioisotope potassium-40 ( 40 K) are often used for radiation education, but their radioactivity is not usually known. In the present study, low-sodium salts (LS salts) were purchased at several shopping malls in Japan, and the radioactivity of 40 K in the LS salts were calculated from the nutritional tables and cutting down rates (CDR) printed on their packages. CDR is the percentage of sodium chloride (NaCl) in common salts replaced with potassium chloride (KCl). Solid disks were fabricated from the LS salts and KCl reagent, and their radiation count rates (cps/g) were measured by GM survey meter and CsI spectrometer. In these measurements, the KCl disk was used to determine the conversion factors (Bq/cps) for determining radioactivity of 40 K in the LS salts. It was found that the experimentally obtained radioactivity generally coincides with that calculated from the nutritional tables, but it does not always coincide with that calculated from CDR.
{"title":"Examination of Low-Sodium Salts for Radiation Education","authors":"T. Kawano","doi":"10.12950/RSM.200714","DOIUrl":"https://doi.org/10.12950/RSM.200714","url":null,"abstract":"Various materials containing the natural radioisotope potassium-40 ( 40 K) are often used for radiation education, but their radioactivity is not usually known. In the present study, low-sodium salts (LS salts) were purchased at several shopping malls in Japan, and the radioactivity of 40 K in the LS salts were calculated from the nutritional tables and cutting down rates (CDR) printed on their packages. CDR is the percentage of sodium chloride (NaCl) in common salts replaced with potassium chloride (KCl). Solid disks were fabricated from the LS salts and KCl reagent, and their radiation count rates (cps/g) were measured by GM survey meter and CsI spectrometer. In these measurements, the KCl disk was used to determine the conversion factors (Bq/cps) for determining radioactivity of 40 K in the LS salts. It was found that the experimentally obtained radioactivity generally coincides with that calculated from the nutritional tables, but it does not always coincide with that calculated from CDR.","PeriodicalId":350737,"journal":{"name":"Radiation Safety Management","volume":" 868","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113947035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The long-term migration of 137 Cs in the environment is mainly through the 137 Cs adsorbed on the dispersed soil particles of various sizes. However, the transfer of 137 Cs from soil to plant, especially rice plant, remains questionable. The objective of this study is to determine the relation among soil characteristics, 137 Cs distribution and transfer factor (TF) of 137 Cs from soil to rice. In this study paddy fields in Kawauchi and Fukushima were chosen. This is because more studies have focused only on one sampling field and there have not been much discussion comparing various fields as envisaged in this study. The results have shown that TF for Kawauchi is 5-fold higher than that of Fukushima. Physicochemical properties of the soils showed that Fukushima soil has less percentage of exchangeable 137 Cs and high percentage of exchangeable K in contrast to Kawauchi soil. These factors likely disturbed the transfer of 137 Cs from soil into the rice plant. Powder X-ray diffraction has shown that Fukushima soil is rich in micaceous minerals which also release a lot of K + to distract the 137 Cs transfer. This study suggests that the presence of micaceous minerals in the soil would be a good amendment for radiocesium-contaminated rice paddy fields in enhancing adsorption of 137 Cs in the soil. However, there is still a need to investigate adsorption kinetics of 137 Cs to ascertain higher values of TF in Kawauchi soil.
{"title":"137Cs Soil to Rice Transfer Factor and Soil Properties: Fukushima and Kawauchi Case Study","authors":"W. Bekelesi, Triyono Basuki, Satoru Nakashima","doi":"10.12950/rsm.220131","DOIUrl":"https://doi.org/10.12950/rsm.220131","url":null,"abstract":"The long-term migration of 137 Cs in the environment is mainly through the 137 Cs adsorbed on the dispersed soil particles of various sizes. However, the transfer of 137 Cs from soil to plant, especially rice plant, remains questionable. The objective of this study is to determine the relation among soil characteristics, 137 Cs distribution and transfer factor (TF) of 137 Cs from soil to rice. In this study paddy fields in Kawauchi and Fukushima were chosen. This is because more studies have focused only on one sampling field and there have not been much discussion comparing various fields as envisaged in this study. The results have shown that TF for Kawauchi is 5-fold higher than that of Fukushima. Physicochemical properties of the soils showed that Fukushima soil has less percentage of exchangeable 137 Cs and high percentage of exchangeable K in contrast to Kawauchi soil. These factors likely disturbed the transfer of 137 Cs from soil into the rice plant. Powder X-ray diffraction has shown that Fukushima soil is rich in micaceous minerals which also release a lot of K + to distract the 137 Cs transfer. This study suggests that the presence of micaceous minerals in the soil would be a good amendment for radiocesium-contaminated rice paddy fields in enhancing adsorption of 137 Cs in the soil. However, there is still a need to investigate adsorption kinetics of 137 Cs to ascertain higher values of TF in Kawauchi soil.","PeriodicalId":350737,"journal":{"name":"Radiation Safety Management","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134349023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Bekelesi, Triyono Basuki, S. Higaki, Satoru Nakashima
{"title":"Distinction of Migration of Strontium-90 and Cesium-137 for Fukushima Soil and Sediment following the Fukushima Accident","authors":"W. Bekelesi, Triyono Basuki, S. Higaki, Satoru Nakashima","doi":"10.12950/rsm.220527","DOIUrl":"https://doi.org/10.12950/rsm.220527","url":null,"abstract":"","PeriodicalId":350737,"journal":{"name":"Radiation Safety Management","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134624915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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