Jayaprakasam Selvakumar, Kumari Anshul, Padala A. Nishad, Bhaskarapillai Anupkumar, Subramanian Srinivasan, Nethapakkam R. Jawahar, Appadurai L. Rufus, Jayantha K. Gayen, Tulasi V. Krishna Mohan
Cerium hydroxide, Ce(OH)4 (Ce), has been synthesised and assessed as a Ru-selective adsorbent for treating alkaline radioactive liquid waste. Infrared spectroscopy, thermal analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy investigations confirmed the successful formation of nanocrystalline Ce from Ce(NO3)3·6H2O. Selective removal of 106Ru from the ion-exchange effluent of intermediate-level liquid waste (ILW) by Ce was assessed using a high-pure germanium (HPGe) gamma-ray spectrometer. The calculated average distribution coefficient (kD) was ∼200 mL/g. The percentage removal of 106Ru using Ce by varying time, [106Ru] and [Ce] was calculated. The adsorption of 106Ru on Ce follows pseudo-second-order and Freundlich isotherms. The calculated Qmax was 93,584 Bq/g. Accelerated leaching studies of the Ru-laden Ce cement product were carried out and found suitable for transport and disposal. Further, Ce-Polyether sulphone (Ce-PES) and Ce-Chitosan (CeC) composites were prepared and assessed for their Ru-uptake capacity for engineering scale application.
氢氧化铈(Ce(OH)4 (Ce))已被合成并评估为一种处理碱性放射性液体废物的 Ru 选择性吸附剂。红外光谱、热分析、扫描电子显微镜和能量色散 X 射线光谱研究证实,Ce(NO3)3-6H2O 成功地形成了纳米晶 Ce。使用高纯锗(HPGe)伽马射线光谱仪评估了 Ce 从中级液体废物(ILW)离子交换流出物中选择性去除 106Ru 的情况。计算得出的平均分布系数(k D)为 200 mL/g。通过改变时间、[106Ru]和[Ce],计算了利用 Ce 去除 106Ru 的百分比。106Ru 在 Ce 上的吸附遵循伪二阶和 Freundlich 等温线。计算得出的最大 Q 值为 93,584 Bq/g。对含有 Ru 的 Ce 水泥产品进行了加速沥滤研究,发现其适合运输和处置。此外,还制备了 Ce 聚醚砜(Ce-PES)和 Ce 壳聚糖(CeC)复合材料,并对其在工程规模应用中的 Ru 吸收能力进行了评估。
{"title":"Nanocrystalline Ce(OH)4-based materials: ruthenium selective adsorbent for highly alkaline radioactive liquid waste","authors":"Jayaprakasam Selvakumar, Kumari Anshul, Padala A. Nishad, Bhaskarapillai Anupkumar, Subramanian Srinivasan, Nethapakkam R. Jawahar, Appadurai L. Rufus, Jayantha K. Gayen, Tulasi V. Krishna Mohan","doi":"10.1515/ract-2023-0194","DOIUrl":"https://doi.org/10.1515/ract-2023-0194","url":null,"abstract":"Cerium hydroxide, Ce(OH)<jats:sub>4</jats:sub> (Ce), has been synthesised and assessed as a Ru-selective adsorbent for treating alkaline radioactive liquid waste. Infrared spectroscopy, thermal analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy investigations confirmed the successful formation of nanocrystalline Ce from Ce(NO<jats:sub>3</jats:sub>)<jats:sub>3</jats:sub>·6H<jats:sub>2</jats:sub>O. Selective removal of <jats:sup>106</jats:sup>Ru from the ion-exchange effluent of intermediate-level liquid waste (ILW) by Ce was assessed using a high-pure germanium (HPGe) gamma-ray spectrometer. The calculated average distribution coefficient (<jats:italic>k</jats:italic> <jats:sub>D</jats:sub>) was ∼200 mL/g. The percentage removal of <jats:sup>106</jats:sup>Ru using Ce by varying time, [<jats:sup>106</jats:sup>Ru] and [Ce] was calculated. The adsorption of <jats:sup>106</jats:sup>Ru on Ce follows pseudo-second-order and Freundlich isotherms. The calculated <jats:italic>Q</jats:italic> <jats:sub>max</jats:sub> was 93,584 Bq/g. Accelerated leaching studies of the Ru-laden Ce cement product were carried out and found suitable for transport and disposal. Further, Ce-Polyether sulphone (Ce-PES) and Ce-Chitosan (CeC) composites were prepared and assessed for their Ru-uptake capacity for engineering scale application.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexandra Becker, Holger Lippold, Jantje Pauline Bäcker, Detlev Belder, Cornelius Fischer
The handling and analysis of gaseous tritium is of interest for hydrogen isotope separation experiments. In this work, we present an easy-to-handle setup for catalytic oxidation to HTO, recovering all of the initially dosed gaseous tritium as determined by LSC, using CuO as a catalyst at a reaction temperature of 900 °C. Aiming to reduce cocktail waste, the LSC determination was downscaled to a microfluidic setup. The performance was evaluated based on the counting efficiency, which was shown to decrease significantly, as the sample volume was reduced to µl amounts, while no changes were observed over a wide range of sample-to-cocktail ratios.
{"title":"An LSC approach for tritium determination in gaseous mixtures optimized with respect to handling, reaction parameters and miniaturization towards microfluidic analysis","authors":"Alexandra Becker, Holger Lippold, Jantje Pauline Bäcker, Detlev Belder, Cornelius Fischer","doi":"10.1515/ract-2023-0262","DOIUrl":"https://doi.org/10.1515/ract-2023-0262","url":null,"abstract":"The handling and analysis of gaseous tritium is of interest for hydrogen isotope separation experiments. In this work, we present an easy-to-handle setup for catalytic oxidation to HTO, recovering all of the initially dosed gaseous tritium as determined by LSC, using CuO as a catalyst at a reaction temperature of 900 °C. Aiming to reduce cocktail waste, the LSC determination was downscaled to a microfluidic setup. The performance was evaluated based on the counting efficiency, which was shown to decrease significantly, as the sample volume was reduced to µl amounts, while no changes were observed over a wide range of sample-to-cocktail ratios.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohamed Fares, Mohammed Messaoudi, Mohamed Yacine Debili, Kassida Negara
Detecting nuclear radiation presents a distinctive challenge, particularly with neutrons, which are neutral particles. The method of direct detection involves the utilization of a converter material, acting as an intermediary. Boron plays a pivotal role in this process, reacting with thermal neutrons to generate alpha particles and lithium, with a notable energy release of 2.314 MeV during the 10B (n,α) 7Li reaction. This facilitates effective identification and measurement of neutrons in radiation detection systems. The paths of the particles α (for E = 1.474 MeV) and Li (for ELi = 0.842 MeV). The active medium of the nuclear detector, typically a gas, undergoes ionization by these highly charged particles, or they form ion pairs that are subsequently collected by electrodes to produce the signal at the detector’s output. Various deposit methods can be used for this purpose, electrophoresis offers a distinct advantage in terms of both simplicity and precision. This study details the utilization of the electrophoresis technique for the deposition of boron on the tube walls of prototype detectors developed within our laboratory.
{"title":"Application of thin boron deposit by electrophoresis as neutron detectors","authors":"Mohamed Fares, Mohammed Messaoudi, Mohamed Yacine Debili, Kassida Negara","doi":"10.1515/ract-2023-0226","DOIUrl":"https://doi.org/10.1515/ract-2023-0226","url":null,"abstract":"Detecting nuclear radiation presents a distinctive challenge, particularly with neutrons, which are neutral particles. The method of direct detection involves the utilization of a converter material, acting as an intermediary. Boron plays a pivotal role in this process, reacting with thermal neutrons to generate alpha particles and lithium, with a notable energy release of 2.314 MeV during the <jats:sup>10</jats:sup>B (n,α) <jats:sup>7</jats:sup>Li reaction. This facilitates effective identification and measurement of neutrons in radiation detection systems. The paths of the particles α (for <jats:italic>E</jats:italic> = 1.474 MeV) and Li (for <jats:italic>E</jats:italic> <jats:sub>Li</jats:sub> = 0.842 MeV). The active medium of the nuclear detector, typically a gas, undergoes ionization by these highly charged particles, or they form ion pairs that are subsequently collected by electrodes to produce the signal at the detector’s output. Various deposit methods can be used for this purpose, electrophoresis offers a distinct advantage in terms of both simplicity and precision. This study details the utilization of the electrophoresis technique for the deposition of boron on the tube walls of prototype detectors developed within our laboratory.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139772817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emily R. Mikeska, Natalie M. Lind, Alexander C. Ervin, Celine Khalife, Joseph P. Karnes, James D. Blakemore
Literature reports have demonstrated that Schiff-base-type ligands can serve as robust platforms for the synthesis of heterobimetallic complexes containing transition metals and the uranyl dication (UO22+). However, efforts have not advanced to include either synthesis of complexes containing second- or third-row transition metals or measurement of the redox properties of the corresponding heterobimetallic complexes, despite the significance of actinide redox in studies of nuclear fuel reprocessing and separations. Here, metalloligands denoted [Ni], [Pd], and [Pt] that contain the corresponding Group 10 metals have been prepared and a synthetic strategy to access species incorporating the uranyl ion (UO22+) has been explored, toward the goal of understanding how the secondary metals could tune uranium-centered redox chemistry. The synthesis and redox characterization of the bimetallic complex [Ni,UO2] was achieved, and factors that appear to govern extension of the chosen synthetic strategy to complexes with Pd and Pt are reported here. Infrared and solid-state structural data from X-ray diffraction analysis of the metalloligands [Pd] and [Pt] show that the metal centers in these complexes adopt the expected square planar geometries, while the structure of the bimetallic [Ni,UO2] reveals that the uranyl moiety influences the coordination environment of Ni(II), including inducement of a puckering of the ligand backbone of the complex in which the phenyl rings fold around the nickel-containing core in an umbrella-shaped fashion. Cyclic voltammetric data collected on the heterobimetallic complexes of both Ni(II) and Pd(II) provide evidence for uranium-centered redox cycling, as well as for the accessibility of other reductions that could be associated with Ni(II) or the organic ligand backbone. Taken together, these results highlight the unique redox behaviors that can be observed in multimetallic systems and design concepts that could be useful for accessing tunable multimetallic complexes containing the uranyl dication.
{"title":"Observations regarding the synthesis and redox chemistry of heterobimetallic uranyl complexes containing Group 10 metals","authors":"Emily R. Mikeska, Natalie M. Lind, Alexander C. Ervin, Celine Khalife, Joseph P. Karnes, James D. Blakemore","doi":"10.1515/ract-2023-0237","DOIUrl":"https://doi.org/10.1515/ract-2023-0237","url":null,"abstract":"Literature reports have demonstrated that Schiff-base-type ligands can serve as robust platforms for the synthesis of heterobimetallic complexes containing transition metals and the uranyl dication (UO<jats:sub>2</jats:sub> <jats:sup>2+</jats:sup>). However, efforts have not advanced to include either synthesis of complexes containing second- or third-row transition metals or measurement of the redox properties of the corresponding heterobimetallic complexes, despite the significance of actinide redox in studies of nuclear fuel reprocessing and separations. Here, metalloligands denoted [Ni], [Pd], and [Pt] that contain the corresponding Group 10 metals have been prepared and a synthetic strategy to access species incorporating the uranyl ion (UO<jats:sub>2</jats:sub> <jats:sup>2+</jats:sup>) has been explored, toward the goal of understanding how the secondary metals could tune uranium-centered redox chemistry. The synthesis and redox characterization of the bimetallic complex [Ni,UO<jats:sub>2</jats:sub>] was achieved, and factors that appear to govern extension of the chosen synthetic strategy to complexes with Pd and Pt are reported here. Infrared and solid-state structural data from X-ray diffraction analysis of the metalloligands [Pd] and [Pt] show that the metal centers in these complexes adopt the expected square planar geometries, while the structure of the bimetallic [Ni,UO<jats:sub>2</jats:sub>] reveals that the uranyl moiety influences the coordination environment of Ni(II), including inducement of a puckering of the ligand backbone of the complex in which the phenyl rings fold around the nickel-containing core in an umbrella-shaped fashion. Cyclic voltammetric data collected on the heterobimetallic complexes of both Ni(II) and Pd(II) provide evidence for uranium-centered redox cycling, as well as for the accessibility of other reductions that could be associated with Ni(II) or the organic ligand backbone. Taken together, these results highlight the unique redox behaviors that can be observed in multimetallic systems and design concepts that could be useful for accessing tunable multimetallic complexes containing the uranyl dication.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hongtao Xia, Yuting Liu, Yang Wang, Zihao Feng, Qi Ren, Jianqi Lv, Yang Li, Yanjun Du, Yun Wang
An innovative phytic acid modified reed straw-derived hydrochar composite (PA-C-RBC) was prepared by using inexpensive reed straw and non-toxic phytic acid for the removal of uranium(VI) from aqueous environment. Several characterization results showed that PA-C-RBC was rough and porous with a large number of hydroxyl, carboxyl, and phosphate groups. The uranium(VI) adsorption process by PA-C-RBC conformed to pseudo-second-order kinetic and Langmuir models, and the theoretical maximal adsorption capacity could attain 418.78 mg/g at pH 5.0. PA-C-RBC had 72.66 % of selectivity and 6772.99 mL/g of distribution coefficient for U(VI). Due to the strong chelating between the hydroxyl and phosphate groups on PA-C-RBC and U(VI), PA-C-RBC had excellent adsorption selectivity. These finding highlighted a high potential for removing U(VI) from aqueous solutions.
{"title":"Incorporation of phytic acid into reed straw-derived hydrochar for highly efficient and selective adsorption of uranium(VI)","authors":"Hongtao Xia, Yuting Liu, Yang Wang, Zihao Feng, Qi Ren, Jianqi Lv, Yang Li, Yanjun Du, Yun Wang","doi":"10.1515/ract-2023-0250","DOIUrl":"https://doi.org/10.1515/ract-2023-0250","url":null,"abstract":"An innovative phytic acid modified reed straw-derived hydrochar composite (PA-C-RBC) was prepared by using inexpensive reed straw and non-toxic phytic acid for the removal of uranium(VI) from aqueous environment. Several characterization results showed that PA-C-RBC was rough and porous with a large number of hydroxyl, carboxyl, and phosphate groups. The uranium(VI) adsorption process by PA-C-RBC conformed to pseudo-second-order kinetic and Langmuir models, and the theoretical maximal adsorption capacity could attain 418.78 mg/g at pH 5.0. PA-C-RBC had 72.66 % of selectivity and 6772.99 mL/g of distribution coefficient for U(VI). Due to the strong chelating between the hydroxyl and phosphate groups on PA-C-RBC and U(VI), PA-C-RBC had excellent adsorption selectivity. These finding highlighted a high potential for removing U(VI) from aqueous solutions.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
When operating and dismantling a nuclear facility that handles uranium, the surrounding soil may be contaminated, emphasizing the need for appropriate treatment and disposal methods for soil waste. This study assessed high-temperature sintering technology for uranium contaminated soil waste to overcome limitations in existing decontamination methods and the volume increase associated with current solidification technology. The sintering process was found to effectively vitrify and re-mineralize complex chemical components in the soil. Sintered bodies were produced under varying conditions, adjusting molding pressure, heating temperature, and time. Optimized conditions resulted in sintered bodies with a volume reduction rate exceeding 30 % and a compressive strength surpassing 10 MPa, indicating a significant impact on the phase conversion and re-mineralization of silt and clay minerals. The soil sintering mechanism was identified through comprehensive microscopic observations and mineral phase change analysis. Leaching evaluations of sintered bodies, made from simulated uranium-contaminated soil, demonstrated their applicability to contaminated soil wastes. Additionally, it was confirmed that the sintering temperature of the soil could be lowered by incorporating a small amount of B2O3, suggesting a means to enhance the economic feasibility of the treatment process. The findings of this study highlight the applicability of pressureless sintering technology, based on glass composite materials, capable of simultaneously reducing and stabilizing uranium-contaminated soil waste.
{"title":"Characterization of glass composite material by pressureless sintering of soil and its application to uranium contaminated soil as a waste form","authors":"Jaewoong Hwang, Jaseung Koo, Kenyoung Lee","doi":"10.1515/ract-2023-0222","DOIUrl":"https://doi.org/10.1515/ract-2023-0222","url":null,"abstract":"When operating and dismantling a nuclear facility that handles uranium, the surrounding soil may be contaminated, emphasizing the need for appropriate treatment and disposal methods for soil waste. This study assessed high-temperature sintering technology for uranium contaminated soil waste to overcome limitations in existing decontamination methods and the volume increase associated with current solidification technology. The sintering process was found to effectively vitrify and re-mineralize complex chemical components in the soil. Sintered bodies were produced under varying conditions, adjusting molding pressure, heating temperature, and time. Optimized conditions resulted in sintered bodies with a volume reduction rate exceeding 30 % and a compressive strength surpassing 10 MPa, indicating a significant impact on the phase conversion and re-mineralization of silt and clay minerals. The soil sintering mechanism was identified through comprehensive microscopic observations and mineral phase change analysis. Leaching evaluations of sintered bodies, made from simulated uranium-contaminated soil, demonstrated their applicability to contaminated soil wastes. Additionally, it was confirmed that the sintering temperature of the soil could be lowered by incorporating a small amount of B<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, suggesting a means to enhance the economic feasibility of the treatment process. The findings of this study highlight the applicability of pressureless sintering technology, based on glass composite materials, capable of simultaneously reducing and stabilizing uranium-contaminated soil waste.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139559238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
U. Tukhtaev, Shakhboz Khasanov, Jaloliddin Fayzullayev, A. Safarov, Bayramali Togaev, Seyedkarim Afsharipour
Abstract We conducted a comprehensive assessment of the Kattakurgan reservoir, alongside adjacent wells and boreholes, to measure the concentrations of natural radionuclides, heavy metals, and associated radiological hazards. Using NaI(Tl) crystal scintillation gamma spectrometers, we determined radionuclide levels in water and sediment. Inductively coupled plasma mass spectrometry (ICP-MS) was employed for heavy metal analysis. Our results showed radionuclide concentrations in reservoir water for 226Ra (0.8 Bq/L), 232Th (0.4 Bq/L), and 40K (0.4 Bq/L) were within the limits set by the World Health Organization (WHO). In contrast, deep well water samples showed elevated 226Ra concentrations (1.5 Bq/L). Sediment samples’ radionuclide levels were in line with UNSCEAR guidelines. Barium was the most notable heavy metal, with a concentration of 68.08 μg/L. While most radiation hazard indices remained within safety limits, the gamma index recorded a value of 1.057 Bq/kg. Our research provides valuable data for water quality assessment. The methods described can be applied to other reservoir studies. Regular monitoring is recommended for continuous safety evaluation, and further studies on biotic samples are suggested to enhance understanding of the reservoir’s ecosystem health.
{"title":"Determination of natural radionuclides and heavy metal concentrations in the groundwater and adjacent areas of the Kattakurgan reservoir, Uzbekistan","authors":"U. Tukhtaev, Shakhboz Khasanov, Jaloliddin Fayzullayev, A. Safarov, Bayramali Togaev, Seyedkarim Afsharipour","doi":"10.1515/ract-2023-0254","DOIUrl":"https://doi.org/10.1515/ract-2023-0254","url":null,"abstract":"Abstract We conducted a comprehensive assessment of the Kattakurgan reservoir, alongside adjacent wells and boreholes, to measure the concentrations of natural radionuclides, heavy metals, and associated radiological hazards. Using NaI(Tl) crystal scintillation gamma spectrometers, we determined radionuclide levels in water and sediment. Inductively coupled plasma mass spectrometry (ICP-MS) was employed for heavy metal analysis. Our results showed radionuclide concentrations in reservoir water for 226Ra (0.8 Bq/L), 232Th (0.4 Bq/L), and 40K (0.4 Bq/L) were within the limits set by the World Health Organization (WHO). In contrast, deep well water samples showed elevated 226Ra concentrations (1.5 Bq/L). Sediment samples’ radionuclide levels were in line with UNSCEAR guidelines. Barium was the most notable heavy metal, with a concentration of 68.08 μg/L. While most radiation hazard indices remained within safety limits, the gamma index recorded a value of 1.057 Bq/kg. Our research provides valuable data for water quality assessment. The methods described can be applied to other reservoir studies. Regular monitoring is recommended for continuous safety evaluation, and further studies on biotic samples are suggested to enhance understanding of the reservoir’s ecosystem health.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139437313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The current work deals with studying the influence of cheap, widespread CaO on improving the γ ray-protection capacity of the lightweight, sealing polyester. Therefore, polyester composites were filled with different concentrations of CaO fillers. The fabricated CaO-reinforced polyester composites’ density ranged between 1.177 g/cm3 and 1.377 g/cm3, when CaO filler concentrations increased between 0 wt% and 60 wt%, respectively. Fabricated composites’ morphology and chemical composition, as well as CaO fillers’ grain size and distribution, were proved using SEM and EDX spectroscopy. Additionally, the influence of CaO fillers on the gamma-ray shielding properties of the fabricated composites was evaluated using the Monte Carlo simulation and confirmed using the experimental measurements. The recorded results show an enhancement in the synthesized composites’ linear attenuation coefficient from 0.091 cm−1 to 0.106 cm−1 at a gamma ray energy of 0.662 MeV. Moreover, the excess in CaO concentration from 0 wt% and 60 wt% reduces the fabricated composites’ half-value thickness values from 7.64 cm to 6.51 cm, respectively.
摘要 当前的工作是研究廉价、广泛使用的氧化钙对提高轻质密封聚酯的γ射线防护能力的影响。因此,聚酯复合材料中填充了不同浓度的 CaO 填料。当 CaO 填料浓度在 0 wt% 和 60 wt% 之间增加时,制备的 CaO 增强聚酯复合材料的密度在 1.177 g/cm3 和 1.377 g/cm3 之间。利用扫描电镜和乙二胺四乙酸(EDX)光谱法证明了制备的复合材料的形貌和化学成分,以及 CaO 填料的粒度和分布。此外,还利用蒙特卡洛模拟评估了 CaO 填料对所制复合材料伽马射线屏蔽性能的影响,并通过实验测量进行了确认。记录结果显示,在伽马射线能量为 0.662 MeV 时,合成复合材料的线性衰减系数从 0.091 cm-1 提高到 0.106 cm-1。此外,氧化钙浓度从 0 wt% 增加到 60 wt%,复合材料的半值厚度值也从 7.64 cm 减小到 6.51 cm。
{"title":"CaO-enhanced polyester for safety: experimental study on fabrication, characterization, and gamma-ray attenuation","authors":"M. Marashdeh, K. A. Mahmoud","doi":"10.1515/ract-2023-0265","DOIUrl":"https://doi.org/10.1515/ract-2023-0265","url":null,"abstract":"Abstract The current work deals with studying the influence of cheap, widespread CaO on improving the γ ray-protection capacity of the lightweight, sealing polyester. Therefore, polyester composites were filled with different concentrations of CaO fillers. The fabricated CaO-reinforced polyester composites’ density ranged between 1.177 g/cm3 and 1.377 g/cm3, when CaO filler concentrations increased between 0 wt% and 60 wt%, respectively. Fabricated composites’ morphology and chemical composition, as well as CaO fillers’ grain size and distribution, were proved using SEM and EDX spectroscopy. Additionally, the influence of CaO fillers on the gamma-ray shielding properties of the fabricated composites was evaluated using the Monte Carlo simulation and confirmed using the experimental measurements. The recorded results show an enhancement in the synthesized composites’ linear attenuation coefficient from 0.091 cm−1 to 0.106 cm−1 at a gamma ray energy of 0.662 MeV. Moreover, the excess in CaO concentration from 0 wt% and 60 wt% reduces the fabricated composites’ half-value thickness values from 7.64 cm to 6.51 cm, respectively.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139437728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Acetonitrile is widely used as a solvent in synthesizing various fluorine-18 positron emission tomography (PET) radiotracers. Acetonitrile is classified as a Class II residual solvent, and due to its inherent toxic properties, the quantity of residual acetonitrile in drug products has to be limited. When working under Good Manufacturing Practices (GMP) during the radiosynthesis of a radiotracer, the aim is to control all solvent concentrations contained in the ready-to-use product. All products must meet predetermined specifications. Rarely, these limits may be exceeded. To avoid eliminating the entire batch, applying a straightforward time-based technique would be desirable to allow the majority of the product to be safely used. This technique should be based on determining a specific time and volume for which the radiotracer can be utilized in the patients after completing quality control analysis. Here, we report a very simple Excel sheet program based on existing mathematical equations that calculates the exact time and volume at which the radiotracer product can be safely administered to a patient.
{"title":"Overcoming the obstacle of excess acetonitrile content in the final fluorine-18 radiotracers","authors":"Mohammed Al-Qahtani","doi":"10.1515/ract-2023-0225","DOIUrl":"https://doi.org/10.1515/ract-2023-0225","url":null,"abstract":"Abstract Acetonitrile is widely used as a solvent in synthesizing various fluorine-18 positron emission tomography (PET) radiotracers. Acetonitrile is classified as a Class II residual solvent, and due to its inherent toxic properties, the quantity of residual acetonitrile in drug products has to be limited. When working under Good Manufacturing Practices (GMP) during the radiosynthesis of a radiotracer, the aim is to control all solvent concentrations contained in the ready-to-use product. All products must meet predetermined specifications. Rarely, these limits may be exceeded. To avoid eliminating the entire batch, applying a straightforward time-based technique would be desirable to allow the majority of the product to be safely used. This technique should be based on determining a specific time and volume for which the radiotracer can be utilized in the patients after completing quality control analysis. Here, we report a very simple Excel sheet program based on existing mathematical equations that calculates the exact time and volume at which the radiotracer product can be safely administered to a patient.","PeriodicalId":21167,"journal":{"name":"Radiochimica Acta","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139379866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}