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Yamamoto, Yusuke*; Watanabe, Takahiro; Niwa, Masakazu; Shimada, Koji
JAEA-Testing 2023-003, 67 Pages, 2024/02
JAEA-Testing-2023-003.pdf:4.63MB
A long-term geosphere stability for geological disposal is evaluated by the past geological environmental changes and modern conditions. Stable hydrogen and oxygen isotope ratios (
D, 
O) of geological samples are useful information to estimate the past environmental changes and modern conditions. Recently, the thermal conversion elemental analyzer and isotope ratio mass spectrometer (TC-EA/IRMS) were installed in the Tono Geoscience Center for D and O measurements of geological samples. In this study, we reported analytical methods of D and O using international standard reference materials. In addition, evaluation tests of uncertainty by repeated analyses of the standards were performed using the TC-EA/IRMS. Furthermore, the D and O analyses by the TC- EA/IRMS were also applied to fault rock samples.
Yanagisawa, Kayo; Matsueda, Makoto; Furukawa, Makoto*; Ishiniwa, Hiroko*; Wada, Toshihiro*; Hirata, Takafumi*; Takagai, Yoshitaka*
Analyst, 148(18), p.4291 - 4299, 2023/09
Times Cited Count：0 Percentile：0(Chemistry, Analytical)Quantitative imaging of trace elements was successfully performed by online isotope dilution laser ablation inductively coupled plasma mass spectrometry (online LA-ICP-IDMS). The sample aerosols produced by LA are mixed online with the mist created from an isotopically enriched spike solution via an in-house cyclonic spray chamber, which has a gas port on the top. Quantification was continuously achieved in each spot; subsequently, quantitative imaging was realized. Fe and Sr were selected as the model elements, and their spot quantifications based on online-isotope dilution. The method was applied to actual biological hard tissues, and the results were compared with electron probe microanalyzer data.
Tomita, Ryohei; Tomita, Jumpei; Suzuki, Daisuke; Yasuda, Kenichiro; Miyamoto, Yutaka
Hosha Kagaku, (48), p.1 - 15, 2023/09
Secondary Ion Mass Spectrometry (SIMS) is the method to detect secondary ions produced by the sputtering of primary ions. SIMS is one of effective method to measure isotopic composition of particles containing nuclear material in environmental sample for safeguards. We are a group member of the International Atomic Energy Agency (IAEA)'s network of analytical laboratories and have developed analytical techniques using SIMS and other mass spectrometers for nuclear safeguards. We will introduce the principle of SIMS and analytical techniques developed by our group to measure isotopic composition of uranium particles which having a particle diameter of micron order in environmental sample for safeguards.
Yasuda, Satoshi; Di
o, W. A.*; Fukutani, Katsuyuki
Vacuum and Surface Science, 66(9), p.514 - 519, 2023/09
Monolayer graphene, representative of atomically thin crystals, has recently shown unexpectedly high proton and deuteron permeability under ambient conditions. It also permeates (filters) hydrogen (deuterium) isotope ion with high selectivity. These results suggest possible ways of developing novel and efficient hydrogen isotope gas enrichment techniques for manufacturing silicon semiconductors, optical fibers, drug development, nuclear fusion, and other related applications. And yet, despite its importance, experimental studies remain scarce and the separation mechanism contentious. Here, we introduce our recent findings on how quantum tunneling of hydrons through graphene could account for the high hydron selectivity of graphene.
Watanabe, Teppei*; Sekine, Yurina; Ikeda-Fukazawa, Tomoko*
Macromolecules, 56(16), p.6217 - 6221, 2023/08
Times Cited Count：1 Percentile：51.7(Polymer Science)To investigate the ability of hydrogels to separate hydrogen isotopes in water, we analyzed the Raman spectra of poly-N,N-dimethylacrylamide (PDMAA) hydrogels containing deuterated water during dehydration. The results show a significant fractionation of hydrogen isotopes during dehydration. The D molar ratio of the hydrogel increases from 0.056 to 
0.2 during dehydration from 90.5 wt% to 5 wt% in water content. Deuterated water preferentially forms hydrogen bonds with hydrophilic groups of the polymer in hydrogels because of the difference in strengths of hydrogen bonds between protium and deuterium. As a result, normal water preferentially evaporates in the initial stage of dehydration, leaving deuterated water in the drying hydrogel. The results suggest that hydrogels are an efficient material for isotope fractionation with evaporation.
Miyamoto, Yutaka; Suzuki, Daisuke; Tomita, Ryohei; Tomita, Jumpei; Yasuda, Kenichiro
Isotope News, (786), p.22 - 25, 2023/04
no abstracts in English
Nagai, Takayuki; Tone, Masaya; Katsuoka, Nanako; Okamoto, Yoshihiro; Baba, Yuji*; Akiyama, Daisuke*
Photon Factory Activity Report 2022 (Internet), 3 Pages, 2023/00
no abstracts in English
Tomita, Jumpei; Tomita, Ryohei; Suzuki, Daisuke; Yasuda, Kenichiro; Miyamoto, Yutaka
KEK Proceedings 2022-2, p.154 - 158, 2022/11
Precise determination of minor U isotopes (
U and 
U) of particles from the safeguard environmental samples is powerful method for detecting the undeclared nuclear activities. In this study, preparation method of U particle was examined to utilize for the minor U isotope determination. The porous silica particles were used as the particle matrix and lutetium was mixed to the impregnation solution as U impregnation indicator for the particle picking. The result of the Scanning Electron Microscope indicated that the contacting the solution with Si particles overnight gently could produce the impregnated particles effectively rather than the mixing them with PFA stick.
Nagai, Takayuki; Okamoto, Yoshihiro; Baba, Yuji*; Akiyama, Daisuke*; Arima, Tatsumi*
Photon Factory Activity Report 2021 (Internet), 2 Pages, 2022/00
no abstracts in English
Cu and 
Cu via the Zn(n, p)Cu and 
Zn(n, np/d)Cu reactions using accelerator neutronsKawabata, Masako*; Motoishi, Shoji*; Ota, Akio*; Motomura, Arata*; Saeki, Hideya*; Tsukada, Kazuaki; Hashimoto, Shintaro; Iwamoto, Nobuyuki; Nagai, Yasuki*; Hashimoto, Kazuyuki*
Journal of Radioanalytical and Nuclear Chemistry, 330(3), p.913 - 922, 2021/12
Times Cited Count：7 Percentile：72.21(Chemistry, Analytical)Both Cu and Cu are promising radionuclides in nuclear medicine. Production yields of these radionuclides were quantified by irradiating 55.4 g of natural zinc with accelerator neutrons. Clinically suitable Cu and Cu yields were estimated by experimental based numerical simulations using 100 g of enriched Zn and Zn, respectively, and elevated neutron fluxes from 40 MeV, 2 mA deuterons. A combined thermal- and resin-separation method was developed to isolate Cu and Cu from zinc, resulting in 73% separation efficiency and 97% zinc recovery. Such methods can provide large scale production of Cu and Cu for clinical applications.
Cs/
Cs isotopic ratio in soil collected near Fukushima Daiichi Nuclear Power Station through mass spectrometryShimada, Asako; Tsukahara, Takehiko*; Nomura, Masao*; Kim, M. S.*; Shimada, Taro; Takeda, Seiji; Yamaguchi, Tetsuji
Journal of Nuclear Science and Technology, 58(11), p.1184 - 1194, 2021/11
Times Cited Count：5 Percentile：65.59(Nuclear Science & Technology)Determining the completeness of nuclear reactor decommissioning is an important step in safely utilizing nuclear power. For example, Cs from the Fukushima Daiichi Nuclear Power Station (FDNPS) accident can be treated as background radioactivity, so determining the origin of Cs is essential. To accomplish this, measuring the Cs/Cs isotope ratio can be useful, so this study optimized a solvent extraction method, with calix[4]arene-bis(t-octylbenzo-crown-6) [BOBCalixC6] in 1-octanol, to purify radioactive Cs, radiocesium, from a solution of major environmental soil elements and mass spectrometry interference elements. This optimized method was applied to Cs purification in soil samples (40 g), and the final solutions contained a total of 10
g/ml of the major soil elements and ng/ml concentrations at most of interfering elements. Soil samples collected near the FDNPS were then purified, and the Cs/Cs isotope ratios were measured, using both thermal ionization mass spectrometry (TIMS) and triple quadrupole induced coupled plasma mass spectrometry (ICP-QQQ). The results of each of these measurements were compared, and we found that Cs isotope ratios obtained by TIMS were more precise, by an order of magnitude, while the ICP-QQQ results possessed good abundance sensitivities. A slightly higher Cs/Cs ratio in the northwest area of the FDNPS was observed, while other areas exhibited similar values, all within the measurement error range, which indicated different origins of radiocesium. These results agreed with previously reported 
Cs/Cs activity distributions, suggesting that this ratio may be useful in identifying radiocesium origins for evaluating future nuclear reactor decommissions.
Cs to web-building spiders, 
, and its pathways; A Preliminary study using stable carbon and nitrogen isotope analysesTanaka, Sota; Kakinuma, Hotaru*; Adachi, Taro*; Atarashi-Andoh, Mariko; Koarashi, Jun
Journal of Nuclear Science and Technology, 58(4), p.507 - 514, 2021/04
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Understanding the pathways of Cs transfer to predatory spiders is useful to assess long-term behavior of Cs in the environment, because spiders obtain food resources from both the grazing and detritus food chains in terrestrial-aquatic linking forest ecosystems. In the present study, we collected spider samples at forest interior and riverside. The sample collection was approximately 6.5 years after the FDNPP accident. Moreover, a transfer factor value (T
) for Cs in spiders was quantified. Stable carbon and nitrogen isotope ratios (
C and 
N) of the spiders were also investigated to estimate the transfer pathways of Cs to the spiders.
N isotopic enrichment plant and its cost for nitride fuel fabrication (Contract research)Takano, Masahide
JAEA-Review 2020-080, 24 Pages, 2021/03
JAEA-Review-2020-080.pdf:1.71MB
Nitride is one of the potential fuel forms for minor actinide transmutation by the accelerator driven system. However, to avoid the 
C production from N by (n, p) reaction in the fuel, the special N
gas highly enriched with N is needed for the fuel fabrication. To realize the availability of such gas has been an important issue. In this report, the degree of N enrichment and gas amount required for the fuel fabrication are shown first, and then among the existing isotopic enrichment methods, N cryogenic distillation is found to be a promising method from the viewpoint of constructing a huge scale plant because of its non-hazardous feature. Some commercial plants for O enrichment based on the similar method have already been operated in Japan. Its technology and components can be applied to the N enrichment plant. Assuming the supply of N gas from a cryogenic distillation plant, a series of enrichment simulation is performed to evaluate the plant size as functions of targeted degree of enrichment and annual production. By using the simulation results, the basic specifications for plant components and equipment are designed. As a result, a huge plant for annual production of 1000 kg N gas with 99% enrichment is found to be technically feasible. The N gas production cost is also evaluated to be approximately 1/30 of the current distribution price. This survey shows the availability of N gas required for the nitride fuel fabrication in both technical and economic aspects.
Sano, Asami; Ito, Shoichi*; Suzumura, Akimasa*; Ueno, Yuichiro*; Yagi, Hikaru*; Inoue, Toru*; Kawazoe, Takaaki*
Koatsuryoku No Kagaku To Gijutsu, 30(2), p.85 - 94, 2020/10
Minerals and rocks exhibit various isotope compositions depending on their origins and histories. In interpreting their isotopic variations, the equilibrium isotope fractionation factor is a key because it depends on the environment parameters such as temperature. Recent studies have shown that the effect of pressure on the isotope fractionation, which was considered negligible compared to temperature, is significant under the conditions of the Earth's interior. In this article we review recent advances in experimental studies to determine the isotope fractionation of iron and hydrogen at high pressure over several GPa, discussing their issues and future perspectives.
Nagai, Takayuki; Okamoto, Yoshihiro; Akiyama, Daisuke*; Uehara, Akihiro*; Fujii, Toshiyuki*; Sekimoto, Shun*
KURNS Progress Report 2019, P. 257, 2020/08
To understand the influence of glass structural change by neutron irradiation and boron isotope composition, glass samples were made from enrichment boric acid reagents and neutron irradiation of those samples was carried out in Pn-2 of KUR. The structural change of glass sample after the irradiation will be estimated in 2020FY. Before neutron irradiation test of glass samples, the Si-O bridging structure difference by boron isotope composition compared by using a Raman spectrometry.
Grund, J.*; Asai, Masato; Blaum, K.*; Block, M.*; Chenmarev, S.*; D
llmann, Ch. E.*; Eberhardt, K.*; Lohse, S.*; Nagame, Yuichiro*; Nagy, Sz.*; et al.
Nuclear Instruments and Methods in Physics Research A, 972, p.164013_1 - 164013_8, 2020/08
Times Cited Count：6 Percentile：60.71(Instruments & Instrumentation)We report on the successful coupling of the Penning-trap mass spectrometry setup TRIGA-TRAP to the research reactor TRIGA Mainz. This offers the possibility to perform direct high-precision mass measurements of short-lived nuclei produced in neutron-induced fission of a 
U target located near the reactor core. An aerosol-based gas-jet system is used for efficient transport of short-lived neutron-rich nuclei from the target chamber to a surface ion source. In conjunction with new ion optics and extended beam monitoring capabilities, the experimental setup has been fully commissioned. The design of the surface ion source, efficiency studies and first results are presented.
Akagi, Hiroshi*; Kumada, Takayuki; Otobe, Tomohito*; Itakura, Ryuji*; Hasegawa, Hirokazu*; Oshima, Yasuhiro*
Chemistry Letters, 49(4), p.416 - 418, 2020/04
Times Cited Count：1 Percentile：4.87(Chemistry, Multidisciplinary)Sonoda, Tetsu*; Katayama, Ichiro*; Wada, Michiharu*; Iimura, Hideki; Sonnenschein, V.*; Iimura, Shun*; Takamine, Aiko*; Rosenbusch, M.*; Kojima, Takao*; Ahn, D. S.*; et al.
Progress of Theoretical and Experimental Physics (Internet), 2019(11), p.113D02_1 - 113D02_12, 2019/11
Times Cited Count：1 Percentile：11.61(Physics, Multidisciplinary)An in-flight separator, BigRIPS, at RIBF in RIKEN provides each experiment with specific nuclides separated from many nuclides produced by projectile fragmentation or in-flight fission. In this process, nuclides other than separated ones are discarded on the slits in BigRIPS, although they include many nuclides interested from the view point of nuclear structure. In order to extract these nuclides for parasitic experiments, we are developing a method using laser ion-source (PALIS). A test experiment with 
Se beam from RIBF has been performed by using a gas cell set in BigRIPS. Unstable nuclides around Se were stopped in the gas cell in accordance with a calculation using LISE code. The stopping efficiency has been estimated to be about 30%. As a next step, we will establish the technique for extracting reaction products from the gas cell.
Yokoyama, Keiichi; Matsuoka, Leo*
Ryoshi Woku No Shin Tenkai; Suri Kozo No Shinka To Oyo, p.228 - 242, 2019/08
Quantum walk is the quantum mechanical counter part of the classical random walk, which is known as mathematical model of diffusion process. By applying this new concept to light-matter interaction, a new isotope separation scheme is shown to be emerged. In addition, its advancements and forthcoming challenges are introduced.
Kurosaki, Yuzuru*; Yokoyama, Keiichi
Universe (Internet), 5(5), p.109_1 - 109_15, 2019/05
Times Cited Count：0 Percentile：0.01(Astronomy & Astrophysics)Regarding rovibrational transitions of diatomic alkali haride molecules, optimal waveform of laser electric field was calculated on the basis of the optimal control theory. In this study, we implemented the polarizability term into the Hamiltonian, which defines the field-molecule interaction. As a result, we obtained waveforms causing both one- and two-photon processes in a relatively high electric field regime, while waveforms causing only one-photon process was observed in a weak filed regime as well as the previous study. These results imply that the effect of two-photon process is successfully taken into account in the optimal control theory calculation. Now we can expect more reliable calculation even for strong laser field.
