{"title":"Measurements of hydrogen deposition velocities by farmland soil using D2 gas.","authors":"Masaru Nagai, Hideki Kakiuchi, Tsuyoshi Masuda","doi":"10.1093/rpd/ncae055","DOIUrl":"https://doi.org/10.1093/rpd/ncae055","url":null,"abstract":"<p><p>Using D2 gas as a substrate, this study investigated the hydrogen deposition velocities of farmland soils around a reprocessing plant located in Rokkasho Village, Aomori, Japan. To determine the hydrogen deposition velocities, closed chambers with fans were set on the soils of farmlands that grow Japanese radishes, and changes in D2 concentration in the chambers were measured by gas chromatography. Results showed hydrogen deposition velocities of six soils were within the range of 1.0 × 10-4 ~ 2.0 × 10-4 m s-1. The heavy water (HDO) formations were detected in the soil after the experiment, showing the oxidation of D2 and conversion to water. Relationships between the obtained hydrogen deposition velocities and environmental conditions such as soil temperature, moisture and porosity were examined. A correlation was found between the hydrogen deposition velocities and soil gas phase rate (r = 0.98, p < 0.05).</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142626824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A new tool for estimation of the in vivo distribution of intake radionuclides.","authors":"Jinghang Wang, Xin Lin, Bo Chen, Weihai Zhuo","doi":"10.1093/rpd/ncae031","DOIUrl":"https://doi.org/10.1093/rpd/ncae031","url":null,"abstract":"<p><p>This study developed a more universal tool for estimating the in vivo distribution of intake radionuclides. The biokinetic models and transfer rates for intake radionuclides were cited from the publications of the International Commission on Radiological Protection (ICRP), and the models were transformed into a series of linear differential equations and numerically solved using the Scipy algorithm in Python. The user interfaces for model selection, data input and in vivo distribution calculations were designed using PyQt5. The calculation results of the new tool are completely consistent with those of the data viewer released by the ICRP and are also very similar to other reported values. The new tool allows users to select and change the biokinetic models and transfer rates and display the in vivo distribution of radionuclides in an image format. It is much more user friendly.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142625430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Radiation dose assessment during dental cone beam computed tomography procedures in Sri Lanka towards establishing a dose reference level.","authors":"Madumali Nissanka, Duminda Satharasinghe, Jeyasingam Jeyasugiththan, Wikum Bandara, Wasundara Wijayasinghe, Indika Weerapperuma, Nadeena Jayasuriya, Ruwan Jayasinghe","doi":"10.1093/rpd/ncae215","DOIUrl":"https://doi.org/10.1093/rpd/ncae215","url":null,"abstract":"<p><p>This study assesses radiation doses in cone beam computed tomography (CBCT) procedures in Sri Lanka, with the goal of establishing initial diagnostic reference levels (DRLs). Data from 1162 retrospective scans across four institutions were analyzed, and the medians of the pooled dose distribution for seven clinical indication categories were presented as the DRL values. The proposed DRLs based on clinical indications are 1013 mGy·cm2 for pathological conditions including cysts, tumors, and lesions, 1307 mGy·cm2 for implant planning, 1266 mGy·cm2 for presurgery assessment, and 1585 mGy·cm2 for evaluation of sinus and nasal pathology, temporomandibular disorder, and facial trauma. Considerable variability in doses across facilities was observed, driven by differences in equipment and imaging practices. Therefore, this study recommends adopting suggested DRL values as benchmarks, standardizing protocols to reduce dose variability, and implementing a national framework for regular updates of DRL values.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142625040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}