Article
Chemistry, Analytical
Liuchao Zhu, Xiaolin Hou, Jixin Qiao
Summary: A novel method was developed for determination of ultra-low level Cs-135 and Cs-137 in seawater, demonstrating successful pre-concentration and measurement of the isotopes. The method was used to investigate water masses exchange in the study region using Cs-135 and Cs-137.
Article
Chemistry, Analytical
Liuchao Zhu, Xiaolin Hou, Jixin Qiao
Summary: The study developed an effective method for simultaneous determination of Cs-135 and Cs-137 in various waste samples. High decontamination factors and chemical yields were achieved, with a detection limit of 3.1 x 10(-14) g/g. The method is simple, rapid, and has been successfully applied in nuclear waste analysis.
Article
Engineering, Environmental
Dorian Zok, Tobias Blenke, Sandra Reinhard, Sascha Sprott, Felix Kegler, Luisa Syrbe, Rebecca Querfeld, Yoshitaka Takagai, Vladyslav Drozdov, Ihor Chyzhevskyi, Serhii Kirieiev, Brigitte Schmidt, Wolfram Adlassnig, Gabriele Wallner, Sergiy Dubchak, Georg Steinhauser
Summary: By analyzing the Cs-135/Cs-137 isotope ratios in environmental samples, it is possible to distinguish the sources of Cs-137 contamination.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Analytical
Anaelle Magre, Beatrice Boulet, Helene Isnard, Sebastien Mialle, Olivier Evrard, Laurent Pourcelot
Summary: The 135Cs/137Cs isotopic ratio is used to trace the origin of radioactive contamination. A new ICP-MS/MS method has been developed for the measurement of this ratio in low activity environmental samples. The method can effectively suppress interferences and achieve high Cs sensitivity and low background levels. Its accuracy has been verified by analyzing certified reference materials and sediment samples affected by the Fukushima fallout.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Francesco Galluccio, Gianmarco Bilancia, Eros Mossini, Izabela Cydzik, Mauro Merlo, Aude Bombard, Elena Macerata, Gabriele Magugliani, Paolo Peerani, Mario Mariani
Summary: The completion of radiological inventory of a nuclear facility is hindered by certain radionuclides with low detectability. Cs-135, a long-lived radionuclide, requires chemical and radiochemical treatments for measurement. A preliminary separation approach combined with a non-radiometric assay is proposed to quantify Cs-135 by measuring Cs-135/Cs-137 isotopic ratio.
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
(2023)
Article
Polymer Science
Guihua Ma, Youxiong Zheng, Yuting Zhou, Li Gao, Bingxin Liu, Xingchang Yu, Lei Zhang
Summary: The copolymers with AMP as a carrier show efficient Cs+ adsorption, with higher adsorption capacity when AMP is located in the shell of micelles. The micelles exhibit excellent stability and capability for regeneration, and optimal adsorption occurs at a solution pH of 7.0. The selective Cs+ adsorption is based on the exchange reaction with NH4+ in the gaps of the AMP carrier.
JOURNAL OF POLYMER RESEARCH
(2021)
Article
Chemistry, Physical
Hao Wang, Guihua Ma, Ke Zhang, Zhi Jia, Yuzhuo Wang, Li Gao, Bingxin Liu
Summary: Salt lake brine from Qinghai, China contains abundant cesium resources with large reserves. Ammonium molybdophosphate (AMP) and zirconium phosphate (ZrP) inorganic ion exchangers are effective adsorbents for Cs+ separation and extraction. However, their solubility in water limits their adsorption capacity in aqueous solutions, resulting in difficulties in their use and recovery. This study developed a polyurethane sponge (PU sponge) coated with dopamine-coated AMP and ZrP as an environmentally friendly adsorbent carrier. The AMP/PU sponge showed superior Cs+ adsorption performance compared to the ZrP/PU sponge, reaching saturation at an adsorbent amount of 0.025 g and maintaining an adsorption efficiency above 80% for Cs+ concentrations of 5-35 mg/L. The adsorption process was found to be spontaneous and feasible, with a higher driving force at high temperatures. The interaction between adsorbent and adsorbate was explained using density functional theory calculations. This Cs+ adsorbent provides design guidelines for efficient and selective removal of Cs+.
Article
Chemistry, Analytical
Hua Zhu, Xin Zhong
Summary: Novel ammonium 12-molybdophosphate loaded mesoporous silica (A-SBA-15) materials were synthesized and used for Cs+ removal. The loading of ammonium 12-molybdophosphate significantly improved Cs+ adsorption capacity. A-SBA-15 showed rapid (20 min) and high Cs+ adsorption (46.8 mg/g). The adsorption mechanism was ion exchange and the process was spontaneous, endothermic, and entropy-increasing.
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
(2023)
Article
Environmental Sciences
Zhen Dong, Jifu Du, Yanliang Chen, Manman Zhang, Long Zhao
Summary: Ammonium molybdophosphate (AMP) immobilized cellulose microspheres can serve as efficient Cs removal adsorbents, showing distinct adsorption kinetics and structural properties, suitable for different pH conditions, and possessing high adsorption capacity and radiation stability.
ENVIRONMENTAL POLLUTION
(2021)
Article
Chemistry, Analytical
Anaelle Magre, Beatrice Boulet, Laurent Pourcelot, Matthieu Roy-Barman, Anne de Vismes Ott, Christophe Ardois
Summary: The Cs-135/Cs-137 isotopic ratio is used to characterize the sources of radioactive contamination in the environment. Existing data for Cs-137 at environmental levels are limited due to interferents and low concentrations. This study developed a new method for extracting and purifying Cs, allowing for analysis of large samples of soil or sediment ash. The method showed excellent chemical performance, with high decontamination factors for interferents.
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
(2022)
Article
Chemistry, Analytical
Asako Shimada
Summary: This article summarizes the characteristics of the Cs-135/Cs-137 isotopic ratio and the latest developments in measurement techniques. Cs-135 is one of the important nuclides to assess the safe disposal of High Level Waste (HLW), but its basic data, such as half-life, have large uncertainties. The measurement of the ratio in environmental samples can be used to study global fallout from nuclear weapons testing and nuclear accidents.
Article
Nuclear Science & Technology
Asako Shimada, Takehiko Tsukahara, Masao Nomura, Min Seok Kim, Taro Shimada, Seiji Takeda, Tetsuji Yamaguchi
Summary: Determining the completeness of nuclear reactor decommissioning is crucial for the safe utilization of nuclear power. This study optimized a solvent extraction method to purify Cs for measuring the Cs-135/Cs-137 isotope ratio, finding different origins of radiocesium in different areas near the Fukushima Daiichi Nuclear Power Station.
JOURNAL OF NUCLEAR SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
O. Zakutevskyy, V. Sydorchuk, M. Kovtun, S. Khalameida, E. Skwarek
Summary: Ammonium molybdophosphate (AMP) was modified through milling in air and deposition onto titania and silica using mechanochemical and sol-gel techniques. The prepared AMP-containing samples were analyzed using XRD, FTIR, nitrogen adsorption-desorption, and potentiometric titration. These samples were tested as sorbents for the removal of Cs+, Sr2+, and UO22+ cations from aqueous solution, showing higher specific adsorption capacity than bulk AMP. Some speculations regarding the mechanism of cation sorption were proposed based on the studies of samples with sorbed cations.
RESEARCH ON CHEMICAL INTERMEDIATES
(2023)
Article
Environmental Sciences
Paolo Porto
Summary: Changes in precipitation trends since 1950 have led to an increase in heavy precipitation events, intensity, and frequency in Southern Italy. This has significant implications for environmental risks such as floods, landslides, and land degradation. The use of fallout radionuclides combined with direct measurements can be a useful tool to identify areas at risk and understand the consequences of climate change on larger areas and over a long-term temporal scale.
JOURNAL OF SOILS AND SEDIMENTS
(2023)
Article
Chemistry, Analytical
Weichao Zhang, Jianfeng Lin, Haitao Zhang, Sui Fang, Chen Li, Xiaowei Yi, Haijun Dang, Yihong Xu, Wei Wang, Jiang Xu
Summary: This study developed a novel analytical method using ICP-MS/MS to determine ultra-trace level Am-241. The interference of polyatomic ions from interfering elements was completely removed, resulting in high measurement sensitivity and low detection limit.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2022)
Article
Environmental Sciences
Keiko Tagami, Shigeo Uchida, Takuro Shinano, Gerhard Prohl
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2020)
Article
Environmental Sciences
Masatoshi Yamada, Jian Zheng
SCIENCE OF THE TOTAL ENVIRONMENT
(2020)
Article
Environmental Sciences
Guosheng Yang, Jian Zheng, Keiko Tagami, Shigeo Uchida, Jing Zhang, Jinlong Wang, Jinzhou Du
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2020)
Article
Geosciences, Multidisciplinary
Liguo Cao, Jian Zheng, Zhengchao Zhou, Wenting Bu, Zhongtang Wang, Wang Zheng, Masatoshi Yamada
Summary: This critical review summarizes and discusses the source term, temporal-spatial distribution, and geochemical behavior of plutonium isotopes in seawater and sediments in the China Seas. The study reveals that global fallout and the Pacific Proving Grounds remain the major source of plutonium in the China Seas, and that plutonium in seawater is scavenged more efficiently in nearshore areas compared to open sea. Future research needs for plutonium in marine environments are also discussed.
Article
Chemistry, Analytical
Guosheng Yang, Jian Zheng, Eunjoo Kim, Shuai Zhang, Hatsuho Seno, Munehiko Kowatari, Tatsuo Aono, Osamu Kurihara
Summary: A method for urinary bioassay of ultra-trace Np-237 and Pu isotopes using SF-ICP-MS and ICP-MS/MS was developed in this study. The method showed high decontamination efficiency and sensitivity, making it suitable for screening activities in unexpected actinide exposure. Validation experiments and practical applications confirmed the effectiveness of the method.
ANALYTICA CHIMICA ACTA
(2021)
Article
Chemistry, Analytical
Shuai Zhang, Guosheng Yang, Jian Zheng, Tatsuo Aono, Shaoming Pan
Summary: A rapid method for analyzing Np-237 and Pu isotopes in steel and concrete samples was developed using HCl-HNO3-NH4HF2 digestion, CaF2/LaF3 co-precipitation, AG MP-1 M resin column separation, and SF-ICP-MS measurement. The method offers lower detection limits and avoids the use of toxic HF, making it suitable for detecting low level Pu and Np in samples.
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
(2021)
Article
Engineering, Environmental
Masatoshi Yamada, Jian Zheng
Summary: The study focuses on Pu239+240 concentrations and Pu-240/Pu-239 atom ratios in seawater from the eastern Indian Ocean to identify Pu sources and transport pathways. It is found that a significant amount of Pu derived from Pacific Proving Grounds nuclear tests has been transported to the studied area through specific ocean currents, with high Pu-240/Pu-239 ratios indicating close-in fallout Pu presence.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Environmental Sciences
Masatoshi Yamada, Jian Zheng
Summary: The study determined Pu-240/Pu-239 atom ratios in seawater samples from the Okinawa Trough, showing greater ratios than global fallout due to close-in fallout Pu from nuclear testing at the Pacific Proving Grounds (PPG). Temporal variability in atom ratios was negligible from 1984 to 2015. Pu sources in the water columns mainly comprised of global fallout and PPG close-in fallout.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2021)
Article
Environmental Sciences
Jian Zheng, Keiko Tagami, Shigeo Uchida, Sanae Shibutani, Keisuke Ishida, Takafumi Hamamoto
Summary: 239Pu and 237Np are long-lived radionuclides that are of importance in the safety assessment of radioactive waste disposal. This study determines the soil-soil solution distribution coefficient (Kd) for these radionuclides using global fallout in soil. The Kd values were found to be higher for 239Pu compared to 237Np in Japanese paddy field soils. The sorption and desorption of Pu isotopes were mainly influenced by Fe and Mn oxides, while the sorption and desorption of 237Np were controlled by ion-exchange reactions and complexation with organic matter.
Article
Environmental Sciences
Fenfen Wang, Jian Zheng, Tatsuo Aono, Shaoming Pan, Wu Men
Summary: This study investigates the impact of the Fukushima Dai-ichi Nuclear Power Plant accident on the deep sea environment in the Northwest Pacific and Central Equatorial Pacific Oceans. The results show the presence of radioactive Cs and Pu in the abyssal sediments, with Cs-134 and Cs-137 reaching the open sea floor of the Northwest Pacific before 2018. The Pacific Proving Ground close-in fallout and global fallout are identified as the main sources of Pu in the sediments. The Kuroshio-Oyashio Extension region is found to be the most affected area by the nuclear fallout.
ENVIRONMENTAL POLLUTION
(2022)
Article
Environmental Sciences
Junwen Wu, Xuemin Zheng, Jisheng Chen, Guosheng Yang, Jian Zheng, Tatsuo Aono
Summary: This paper reviews the knowledge on plutonium isotopic composition and activity concentrations resulting from the Fukushima Daiichi Nuclear Power Plant accident. The study reveals the characteristic values and spatial distributions of plutonium in the area. It is clarified that the contamination is restricted to a terrestrial area, while plutonium in the Northwest Pacific Ocean comes from other sources. The findings provide valuable information for future environmental risk assessment and geochemical studies.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2022)
Article
Environmental Sciences
Hai Wang, Youyi Ni, Wu Men, Zhongtang Wang, Min Liu, Detao Xiao, Jian Zheng
Summary: The source and vertical distribution of 137Cs, 239+240Pu, and 241Am in a soil core from Hunan Province, China were investigated. The concentrations of these radionuclides were higher in the upper layers of soil and lower in the lower layers. Their migration velocities differed, with Am having a faster migration velocity than Pu and Cs. The presence of these nuclides may be attributed to global fallout, while soil properties could influence their migration behavior.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2022)
Article
Agriculture, Multidisciplinary
Keiko Tagami, Shigeo Uchida, Nobuyoshi Ishii, Jian Zheng
Summary: When artificial radionuclides are released into the atmosphere, they can directly deposit onto crop surfaces and affect human radiation dose. The mass interception coefficient is an important parameter for estimating radionuclide concentrations in crops. However, data on this coefficient, especially for radiostrontium, are limited. In this study, the researchers used global fallout 90Sr data and naturally occurring 7Be data to enhance the mass interception coefficient data for leafy crops. These data can be valuable for estimating radioactivity contamination levels of radiostrontium on leafy crops in nuclear emergency situations.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2022)
Article
Chemistry, Analytical
Shuai Zhang, Zhiyong Liu, Guosheng Yang, Jian Zheng, Shaoming Pan, Tatsuo Aono, Aya Sakaguchi
Summary: A new method has been developed to solve the difficulties in analyzing Np-237 in seawater, and accurate measurements have been obtained. This method has low method detection limits and high sample throughput, which is of great significance for evaluating the impact of radioactive wastewater discharge on the marine ecological system.
ANALYTICAL CHEMISTRY
(2023)
Article
Environmental Sciences
Jian Zheng, Keiko Tagami, Shigeo Uchida, Sanae Shibutani, Keisuke Ishida, Takafumi Hamamoto
Summary: In this study, the soil-soil solution distribution coefficient (Kd, L/kg) of 237Np and 239Pu in Japanese upland soils were assessed. The results showed that the Kd value of 239Pu was one order of magnitude higher than that of 237Np in Japanese upland soils.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2023)
