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JAEA Reports

Stable hydrogen and oxygen isotope analyses of geological samples using a thermal conversion elemental analyzer-isotope ratio mass spectrometer at Tono Geoscience Center

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 ($$delta$$D, $$delta$$$$^{18}$$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 $$delta$$D and $$delta$$$$^{18}$$O measurements of geological samples. In this study, we reported analytical methods of $$delta$$D and $$delta$$$$^{18}$$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 $$delta$$D and $$delta$$$$^{18}$$O analyses by the TC- EA/IRMS were also applied to fault rock samples.

Journal Articles

Development of analytical techniques for isotopic composition determination of uranium particles in environmental sample for safeguards with Secondary Ion Mass Spectrometry

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.

JAEA Reports

Proceedings of the 34th Meeting for Tandem Accelerators and their Associated Technologies

Kabumoto, Hiroshi; Nakagawa, Sohei; Matsuda, Makoto

JAEA-Conf 2022-002, 146 Pages, 2023/03

JAEA-Conf-2022-002.pdf:9.89MB

"The 34th Meeting for Tandem Accelerators and their Associated Technologies" was held on July 21-22, 2022 organized by Nuclear Science Research Institute of the Japan Atomic Energy Agency. This meeting was held only on-line for preventing the spread of COVID-19 infection. The purpose of this meeting is contribution of development for related technology and of management of facilities through exchange of information among the researchers and engineers using and operating electrostatics accelerator facilities like tandem accelerators. There were 25 presentations which contains current status report of facility, technical development of accelerator, research of application. The total number of participants was a hundred, from 26 universities, research organizations and industries. This meeting consisted of only oral session, a poster session was not carried out because of on-line meeting. This proceeding compiles the contents of report papers in the meeting.

Journal Articles

Development of an ion funnel reaction cell for suppression of isobaric interference in chrorin-36 dating

Jinno, Satoshi; Fujita, Natsuko; Tanuma, Hajime*

Dai-23-Kai AMS Shimpojiumu Hokokushu, p.89 - 92, 2022/12

The measurement of chlorine-36 ($$^{36}$$Cl) in AMS, which is important for the dating of saline groundwater, is more difficult than other nuclides due to the isobaric interference by sulfur-36 ($$^{36}$$S). In general, acceleration voltages of 6 MV or higher are required to separate $$^{36}$$Cl and $$^{36}$$S. Therefore, this study aims to develop an ion funnel reaction cell and incorporate it into the low energy side of JAEA-AMS-TONO-5MV to selectively suppress $$^{36}$$S.

Journal Articles

Frontiers of studies utilizing accelerator mass spectrometry in geoscience

Honda, Maki

Journal of the Mass Spectrometry Society of Japan, 70(4), p.282 - 283, 2022/12

The development of measurement and chemical separation techniques in the accelerator mass spectrometry (AMS) method has enabled highly sensitive analysis of $$^{244}$$Pu (half-life 8.1$$times$$10$$^{7}$$ years), $$^{60}$$Fe (half-life 2.62$$times$$10$$^{6}$$ years), and $$^{90}$$Sr (half-life 28.9 years) in AMS. For example, the study analyzing $$^{244}$$Pu in ferromanganese crust samples successfully quantified $$^{244}$$Pu from outside the solar system, which had been hidden by $$^{244}$$Pu from nuclear tests. Furthermore, the research has revealed that $$^{244}$$Pu is produced in neutron star mergers, etc., leading to unraveling the production sites where the heavy elements originate. This topic highlights the frontline of studies on $$^{244}$$Pu, $$^{60}$$Fe, and $$^{90}$$Sr utilizing AMS.

Journal Articles

Challenging studies by accelerator mass spectrometry for the development of environmental radiology; Status report on the analysis of $$^{90}$$Sr and $$^{135}$$Cs by AMS

Honda, Maki; Martschini, M.*; Wieser, A.*; Marchhart, O.*; Lachner, J.*; Priller, A.*; Steier, P.*; Golser, R.*; Sakaguchi, Aya*

JAEA-Conf 2022-001, p.85 - 90, 2022/11

Accelerator mass spectrometry (AMS) is an analytical method that combines mass spectrometry with a tandem accelerator, which has been used mainly in nuclear physics experiments. AMS is used to measure radionuclides with half-lives of 10$$^{3}$$-10$$^{8}$$ years. For radionuclides with half-lives of this order, the method of measuring their mass is 10$$^{3}$$-10$$^{6}$$ times more sensitive than measuring their activity. Because of this advantage, AMS has been widely applied in Earth and planetary sciences, atomic energy research, and other fields. Among the various studies, Wallner et al. (2021, 2016) have achieved excellent work in Earth and planetary sciences. For example, they have attained the ultra-sensitive analysis of $$^{60}$$Fe and $$^{244}$$Pu in environmental samples. These are radionuclides produced by rapid-neutron-capture (r-process) nucleosynthesis. Our recent work shows that a new AMS system (VERA, University of Vienna), which combines laser isobaric separation and a typical AMS system, has been successfully applied to the ultra-sensitive determination of $$^{90}$$Sr and $$^{135}$$Cs in environment. For $$^{90}$$Sr in environmental samples, the $$beta$$-ray measurement by the milking of the daughter nuclide $$^{90}$$Y is still the principal method, which takes 3-6 weeks. The new AMS method has a detection limit of $$<$$ 0.1 mBq, which is comparable to that of $$beta$$-ray measurement, with a more straightforward chemical treatment than $$beta$$-measurement. Our achievement demonstrates that AMS can be a practical new method for determining $$^{90}$$Sr in the environment.

Journal Articles

Measurement of fission-fragment mass distributions in the multinucleon transfer channels of the $$^{18}$$O+$$^{237}$$Np reaction

Vermeulen, M. J.; Nishio, Katsuhisa; Hirose, Kentaro; Kean, K. R.; Makii, Hiroyuki; Orlandi, R.; Tsukada, Kazuaki; Tsekhanovich, I.*; Andreyev, A. N.; Ishizaki, Shoma*; et al.

Physical Review C, 102(5), p.054610_1 - 054610_11, 2020/11

 Times Cited Count:5 Percentile:51.79(Physics, Nuclear)

Journal Articles

First online operation of TRIGA-TRAP

Grund, J.*; Asai, Masato; Blaum, K.*; Block, M.*; Chenmarev, S.*; D$"u$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:59.94(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 $$^{235}$$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.

Journal Articles

Organ absorbed dose estimation reflecting specific organ masses with simple scaling of reference doses using the organ masses

Manabe, Kentaro; Koyama, Shuji*

Radiation Protection Dosimetry, 189(4), p.489 - 496, 2020/05

AA2019-0343.pdf:0.67MB

 Times Cited Count:1 Percentile:11.8(Environmental Sciences)

It is important for radiation protection in diagnostic nuclear medicine to estimate organ absorbed doses in consideration of person-specific parameters. This study proposes a straightforward method for estimating organ doses which reflect an individual organ masses by scaling the reference doses based on the reference human models using the inverse ratio of the individual masses to the reference organ masses. The method was tested for the administration cases of $$^{rm 99m}$$Tc-labelled colloids and $$^{123}$$I-labelled sodium iodine to confirm the effectiveness of the method. The discrepancies of the doses estimated by the method were sufficiently small in terms of solid organs.

Journal Articles

Effects of multichance fission on isotope dependence of fission fragment mass distributions at high energies

Tanaka, Shoya; Aritomo, Yoshihiro*; Miyamoto, Yuya*; Hirose, Kentaro; Nishio, Katsuhisa

Physical Review C, 100(6), p.064605_1 - 064605_6, 2019/12

 Times Cited Count:13 Percentile:78.7(Physics, Nuclear)

Fission fragment mass distributions of $$^{234-240}$$U, $$^{236-242}$$Np, and $$^{238-244}$$Pu are studied using the Langevin approach in the widely excitation energy range as $$E^{*}$$ = 15-55 MeV. In the present calculation, neutron emission before fission, so called multichance fission, was introduced. The calculated results well demonstrated the experimental data, which shows the double-peak structure up to the highest excitation energies and the clear dependence on the initial fissioning nuclides. The trend is nicely correlated with the neutron binding energy of the compound nucleus that dominates the neutron emission probability before fission.

Journal Articles

On-site measurement of nuclear material by using the fast neutron direct interrogation method

Komeda, Masao

Bunseki, 2019(10), p.459 - 461, 2019/10

no abstracts in English

Journal Articles

U-Pb dating of calcium carbonate using LA-ICP-MS

Yokoyama, Tatsunori

Isotope News, (764), p.11 - 14, 2019/08

no abstracts in English

Journal Articles

A Spectroscopic technique for analysis developed in the field of unclear energy

Kusaka, Ryoji

Bunko Kenkyu, 67(6), p.239 - 240, 2018/12

A spectroscopic technique for analysis developed by collaboration between Japan Atomic Energy Agency (JAEA) and Quantum and Radiological Science and Technology (QST) is discussed for readers outside the field of nuclear energy. This paper introduces a quantitative analysis for $$^{107}$$Pd radioisotope contained in a spent nuclear fuel by using laser-induced photoreduction and inductively coupled plasma mass spectrometry (ICP-MS). The importance and problems of quantitative analysis for radioisotopes in spent nuclear fuels are described, and the principle, advantages, and future applications of the spectroscopic technique are discussed.

Journal Articles

Effect of surface conditions of the filament used in thermal ionization mass spectrometry on an uranium isotopic measurement

Taguchi, Shigeo; Miyauchi, Hironari*; Horigome, Kazushi; Yamamoto, Masahiko; Kuno, Takehiko

Bunseki Kagaku, 67(11), p.681 - 686, 2018/11

In thermal ionization mass spectrometry, de-gassing is one of the important treatments to release impurities of filaments and to minimize the influence of background. In this work, the effect of the surface change in the tungsten filament induced by the conductively heating treatment on uranium isotopic ($$^{235}$$U/$$^{238}$$U) measurement has been investigated. It was found that the conductively heating treatment of the filament has the effect of smoothing the surface of the filament and also has the effect of improving the deposition of the sample on the filament surface. As a result of either these effects, the precision of uranium isotopic ($$^{235}$$U/$$^{238}$$U) measurement was improved.

Journal Articles

Trace analysis for nuclear non-proliferation and security

Esaka, Fumitaka

Bunseki, 2018(10), p.408 - 411, 2018/10

Recent development of analytical techniques for identification of particles containing nuclear materials, isotope ratio analysis of uranium and plutonium using mass spectrometry, and age determination is described in this paper. These techniques are successfully applied to the trace analysis for nuclear non-proliferation.

Journal Articles

Rapid separation of zirconium using microvolume anion-exchange cartridge for $$^{93}$$Zr determination with isotope dilution ICP-MS

Asai, Shiho; Hanzawa, Yukiko; Konda, Miki; Suzuki, Daisuke; Magara, Masaaki; Kimura, Takaumi; Ishihara, Ryo*; Saito, Kyoichi*; Yamada, Shinsuke*; Hirota, Hideyuki*

Talanta, 185, p.98 - 105, 2018/08

 Times Cited Count:8 Percentile:31.52(Chemistry, Analytical)

Estimating the risks associated with radiation from long-lived fission products (LLFP) in radioactive waste is essential to ensure the long-term safety of potential disposal sites. In this study, the amount of $$^{93}$$Zr, a LLFP, was determined by ICP-MS after separating Zr from a spent nuclear fuel solution using a microvolume anion-exchange cartridge (TEDA cartridge). The TEDA cartridge achieved highly selective separation of Zr regardless of its small bed volume of 0.08 cm$$^{3}$$. The time taken to complete the Zr separation was 1.2 min with a flow rate of 1.5 mL/min, which was 10 times faster than that for a conventional anion-exchange resin column. Almost all the other elements were removed, leading to accurate measurement of $$^{93}$$Zr. The result connects experimental value to theoretical prediction provided by ORIGEN2, which requires verification. With the measured value, we demonstrated that the theoretical value is reliable enough to estimate radiation risks.

Journal Articles

Model calculation of Cr dissolution behavior of ODS ferritic steel in high-temperature flowing sodium environment

Otsuka, Satoshi; Tanno, Takashi; Oka, Hiroshi; Yano, Yasuhide; Kato, Shoichi; Furukawa, Tomohiro; Kaito, Takeji

Journal of Nuclear Materials, 505, p.44 - 53, 2018/07

AA2017-0603.pdf:1.7MB

 Times Cited Count:2 Percentile:20.74(Materials Science, Multidisciplinary)

A calculation model was constructed to systematically study the effects of environmental conditions (i.e. Cr concentration in sodium, test temperature, axial temperature gradient of fuel pin, and sodium flow velocity) on Cr dissolution behavior. Chromium dissolution was largely influenced by small changes in Cr concentration (i.e. chemical potential of Cr) in liquid sodium in the model calculation. Chromium concentration in sodium coolant, therefore, should be recognized as a critical parameter for the prediction and management of Cr dissolution behavior in the sodium-cooled fast reactor (SFR) core. Because the fuel column length showed no impact on dissolution behavior in the model calculation, no significant downstream effects possibly take place in the SFR fuel cladding tube due to the much shorter length compared with sodium loops in the SFR plant and the large axial temperature gradient. The calculated profile of Cr concentration along the wall-thickness direction was consistent with that measured in BOR-60 irradiation test where Cr concentration in sodium bulk flow was set at 0.07 wt ppm in the calculation.

Journal Articles

Cutting-edge studies on nuclear data for continuous and emerging need, 3; Recent advancement of fission studies; Experimental and theoretical approaches

Nishio, Katsuhisa; Chiba, Satoshi*

Nihon Genshiryoku Gakkai-Shi ATOMO$$Sigma$$, 59(12), p.717 - 721, 2017/12

no abstracts in English

Journal Articles

Four-dimensional Langevin approach to low-energy nuclear fission of $$^{236}$$U

Ishizuka, Chikako*; Usang, M. D.*; Ivanyuk, F. A.*; Maruhn, J. A.*; Nishio, Katsuhisa; Chiba, Satoshi

Physical Review C, 96(6), p.064616_1 - 064616_9, 2017/12

 Times Cited Count:60 Percentile:97.54(Physics, Nuclear)

Journal Articles

Chemical state and isotope ratio analysis of individual uranium particles by a combination of micro-Raman spectroscopy and secondary ion mass spectrometry

Yomogida, Takumi; Esaka, Fumitaka; Magara, Masaaki

Analytical Methods, 9(44), p.6261 - 6266, 2017/11

 Times Cited Count:9 Percentile:55.41(Chemistry, Analytical)

A combination of micro-sampling, micro-Raman spectroscopy (MRS), and secondary ion mass spectrometry (SIMS) was applied to the characterization of individual uranium particles. Reference particles with U$$_{3}$$O$$_{8}$$ (NBL CRM U010) and UO$$_{2}$$ were identified by scanning electron microscopy combined with energy dispersive X-ray detection (SEM-EDX) and transferred onto grassy carbon substrates by micro-sampling. The crystalline phases of the reference particles with diameters ranging from 1 $$mu$$m to 5 $$mu$$m were determined non-destructively by using MRS thanks to the optimization of laser power at the measurement. Isotope ratios were also determined with SIMS after the MRS analysis and were consistent with values in the literature. These results indicate that chemical forms and isotope ratios of individual uranium particles as small as 1 $$mu$$m can be analyzed efficiently by using the proposed method.

325 (Records 1-20 displayed on this page)