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-ray analysisKinoshita, Norikazu*; Noto, Takuma*; Nakajima, Hitoshi*; Kosako, Kazuaki*; Kato, Takahiro*; Kuroiwa, Yoichi*; Kurabe, Misako*; Sasaki, Yuki*; Torii, Kazuyuki*; Maeda, Makoto; et al.
Journal of Radioanalytical and Nuclear Chemistry, 332(2), p.479 - 486, 2023/02
Times Cited Count：0 Percentile：0.01(Chemistry, Analytical)Kato, Takuma*; Nagaoka, Mika; Guo, H.*; Fujita, Hiroki; Aida, Taku*; Smith, R. L. Jr.*
Environmental Science and Pollution Research, 28(39), p.55725 - 55735, 2021/10
Times Cited Count：0 Percentile：0(Environmental Sciences)In this work, hydrothermal leaching was applied to simulated soils (clay minerals vermiculite, montmorillonite, kaolinite) and actual soils (Terunuma, Japan) to generate organic acids with the objective to develop an additive-free screening method for determination of Sr in soil. Stable strontium (SrCl
) was adsorbed onto soils for study and ten organic acids were evaluated for leaching Sr from simulated soils under hydrothermal conditions (120 to 200
C) at concentrations up to 0.3 M. For strontium-adsorbed vermiculite (Sr-V), 0.1 M citric acid was found to be effective for leaching Sr at 150C and 1 h treatment time. Based on these results, the formation of organic acids from organic matter in Terunuma soil was studied. Hydrothermal treatment of Terunuma soil produced a maximum amount of organic acids at 200C and 0.5 h reaction time. To confirm the possibility for leaching of Sr from Terunuma soil, strontium-adsorbed Terunuma soil (Sr-S) was studied. For Sr-S, hydrothermal treatment at 200C for 0.5 h reaction time allowed 40% of the Sr to be leached at room temperature, thus demonstrating an additive-free method for screening of Sr in soil. The additive-free hydrothermal leaching method avoids calcination of solids in the first step of chemical analysis and has application to both routine monitoring of metals in soils and to emergency situations.
X raysOkumura, Takuma*; Azuma, Toshiyuki*; Bennet, D. A.*; Caradonna, P.*; Chiu, I. H.*; Doriese, W. B.*; Durkin, M. S.*; Fowler, J. W.*; Gard, J. D.*; Hashimoto, Tadashi; et al.
Physical Review Letters, 127(5), p.053001_1 - 053001_7, 2021/07
Times Cited Count：15 Percentile：80.44(Physics, Multidisciplinary)We observed electronic X rays emitted from muonic iron atoms using a superconducting transition-edge-type sensor microcalorimeter. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic 
and 
X rays together with the hypersatellite X rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the 
-shell electrons, accompanied by electron side-feeding. Assisted by a simulation, this data clearly reveals the electronic - and -shell hole production and their temporal evolution during the muon cascade process.
Takasaki, Koji; Yasumune, Takashi; Hashimoto, Makoto; Maeda, Koji; Kato, Masato; Yoshizawa, Michio; Momose, Takumaro
JAEA-Review 2019-003, 48 Pages, 2019/03
JAEA-Review-2019-003.pdf:3.81MB
June 6, 2017, at Plutonium Fuel Research Facility in Oarai Research and Development Center of JAEA, when five workers were inspecting storage containers containing plutonium and uranium, resin bags in a storage container ruptured, and radioactive dust spread. Though they were wearing a half face mask respirator, they inhaled radioactive materials. In the evaluation of the internal exposure dose, the aerodynamic radioactive median diameter (AMAD) is an important parameter. We measured 14 smear samples and a dust filter paper with imaging plates, and estimated the AMAD by image analysis. As a result of estimating the AMAD, from the 14 smear samples, the AMADs are 4.3 to 11 
m or more in the case of nitrate plutonium, and the AMADs are 5.6 to 14 m or more in the case of the oxidized plutonium. Also, from the dust filter paper, the AMAD is 3.0 m or more in the case of nitrate plutonium, and the AMAD is 3.9 m or more in the case of the oxidized plutonium.
C collected by precipitation and gas-strip methods for dating groundwaterNakata, Kotaro*; Hasegawa, Takuma*; Iwatsuki, Teruki; Kato, Toshihiro
Radiocarbon, 58(3), p.491 - 503, 2016/09
Times Cited Count：5 Percentile：21.26(Geochemistry & Geophysics)Dissolved inorganic carbon (DIC) for C analysis of groundwater is usually extracted by a gas-strip or precipitation method. In this study, the certainty of the two methods for C dating were confirmed. DIC and C concentrations obtained by the gas-strip method were close to the theoretically predicted C value. Conversely, the C value obtained by the precipitation method always showed higher values than the predicted values. The difference in C value between gas-strip and precipitation methods was assumed to arise owing to contamination of modern carbon used in the precipitation method. The applicability of the precipitation method for groundwater should be considered carefully according to the DIC, C concentration of groundwater and purpose of the study being conducted.
+ 
Li reactions using the continuum-discretized coupled-channels methodIchinkhorloo, D.*; Matsumoto, Takuma*; Hirabayashi, Yoshiharu*; Kato, Kiyoshi*; Chiba, Satoshi
Journal of Nuclear Science and Technology, 48(11), p.1357 - 1360, 2011/10
Times Cited Count：6 Percentile：44.16(Nuclear Science & Technology)The + Li reactions are important not only from the basic interest of the system but also from the application point of view. In this work, we study Li breakup reactions of incident neutron energies 11.5, 14.1 and 18.0 MeV by applying an + 
cluster model to 
Li and using the continuum-discretized coupled-channels approach. At the present energy, our calculation gives almost good agreement with experimental data.
Li(
)Li
reactions with the microscopic coupled-channels methodMatsumoto, Takuma*; Ichinkhorloo, D.*; Hirabayashi, Yoshiharu*; Kato, Kiyoshi*; Chiba, Satoshi
Physical Review C, 83(6), p.064611_1 - 064611_6, 2011/06
Times Cited Count：21 Percentile：75.45(Physics, Nuclear)We investigate Li()Li
reactions by using the continuum-discretized coupled-channels method with the complex Jeukenne-Lejeune-Mahaux effective nucleon-nucleon interaction. In this study, the Li nucleus is described by a d + cluster model. The calculated elastic cross sections for incident energies between 7.47 and 24.0 MeV are in good agreement with experimental data. Furthermore, we show that the neutron spectra for Li breakup states measured at selected angular points and incident energies can be also reproduced systematically.
Ishii, Katsunori; Suzuki, Masahiro; Yamamoto, Takuma; Kihara, Yoshiyuki; Kato, Yoshiyuki; Kurita, Tsutomu; Yoshimoto, Katsunobu; Yasuda, Masatoshi*; Matsusaka, Shuji*
Journal of Chemical Engineering of Japan, 42(5), p.319 - 324, 2009/05
Times Cited Count：7 Percentile：29.69(Engineering, Chemical)The flowability of coarse particles has been experimentally investigated using the vibrating tube method, to evaluate the applicability of this method to MOX (mixed oxide of PuO and UO) particles which are nuclear fuel used for electric power production. Five sizes of non-radioactive model particles, smaller than 850 micrometers, made of ZrO were prepared, and the experiments were carried out using vibrating tubes with an outlet diameter from 2 to 4 mm. The outlet diameter significantly affected the flowability measurements. When using the tube with a 4-mm-outlet diameter, the flowability of all the model particles was successfully measured. The inclination angle of the tube, also, affected the flowability measurements. From the advantages of high sensitivity, short measurement time, simple structure, and easy operation, the vibrating tube method is expected to be applied to the remote flowability measurement of the MOX particles.
Suzuki, Masahiro; Ishii, Katsunori; Yamamoto, Takuma; Kihara, Yoshiyuki; Kato, Yoshiyuki; Kurita, Tsutomu; Yoshimoto, Katsunobu; Fujii, Kanichi
Proceedings of Global Congress on Microwave Energy Applications (GCMEA 2008/MAJIC 1st), p.501 - 504, 2008/08
The natural resources, oil and uranium, would dry up around the midway of this century. FBR cycle most probably rescues this difficult situation. Mass production of MOX fuel for FBR, therefore, is the supreme subject to Japanese energy strategy. For this subject, we are attacking with Microwave heating technology. Up to present, we have succeeded to produce excellent PuO/UO bulk, 2 kgMOX/batch, advancing toward the mass production target, 5 kgU/h for one batch.
thin film detector for neutronsIshida, Takekazu*; Nishikawa, Masatoshi*; Fujita, Yoshifumi*; Okayasu, Satoru; Katagiri, Masaki*; Sato, Kazuo*; Yotsuya, Tsutomu*; Shimakage, Hisashi*; Miki, Shigehito*; Wang, Z.*; et al.
Journal of Low Temperature Physics, 151(3-4), p.1074 - 1079, 2008/05
Times Cited Count：36 Percentile：77.99(Physics, Applied)The superconducting neutron detector using high-quality 
B-enriched MgB thin films at higher operating temperatures has been proposed, where a resistance change induced by the nuclear reaction of neutron and B in MgB is used to detect a neutron. Cold neutrons from a nuclear research reactor irradiated the MgB detector, and the output voltage was clearly observed through a low-noise amplifier by using a digital oscilloscope. The out-of-equilibrium thermodynamics was investigated by means of the time-dependent Ginzburg-Landau equations by using the Earth Simulator.
neutron detectorsMachida, Masahiko; Kano, Takuma*; Koyama, Tomio*; Kato, Masaru*; Ishida, Takekazu*
Journal of Low Temperature Physics, 151(1), p.58 - 63, 2008/04
Times Cited Count：11 Percentile：46(Physics, Applied)We perform large-scale numerical simulations on the non-equilibrium superconducting dynamics after a neutron capture at the superconducting transition edge in MgB by solving the time-dependent Ginzburg-Landau equation coupled with the Maxwell and the heat diffusion equations. The simulations are carried out under the current-biased condition in order to explain experimental results made in the JAEA reactor JRR-3, and the time scale of the obtained voltage signal is found tobe almost consistent with the experiments. Moreover, the time evolution of the voltage signal is connected with that of the spatial profile of the superconducting order parameter.
Kagohara, Kyoko*; Imaizumi, Toshifumi*; Miyauchi, Takahiro*; Sato, Hiroshi*; Uchida, Takuma*; Echigo, Tomoo*; Ishiyama, Tatsuya*; Matsuta, Nobuhisa*; Okada, Shinsuke*; Ikeda, Yasutaka*; et al.
Chigaku Zasshi, 115(6), p.691 - 714, 2006/12
The eastern marginal fault zone of the Yokote Basin is one of seismogenic reverse faults developed in Northeast Japan, generating the 1896 Riku-u Earthquake (M7.2). We discussed the relationship among fault traces, geomorphic displacements and fault geometries on the Senya fault, based on a data from high-resolution seismic reflection profiling, investigations in tectonic geomorphology and structural geology, with the help of the balanced cross section method. By the restoring the balanced cross sections, the horizontal shortening amount is estimated to be totally 3 km through the thrust system, and the thrusting is retroactive to 2.4 Ma. Depending on the strike of fault traces and the morphotectonic features, the Senya fault is subdivided into three, the northern, central and southern portion. The initiation of thrust front migration is ca.1.6 Ma at the central portion and 0.6 Ma at the northern portion. This means that the central portion preceded the northern portion as an emergent fault, and suggests that the initial propagated fault extends from the fault end to the boundary fault.
Otsuka, Naohiko; Aikawa, Masayuki*; Suda, Takuma*; Naito, Kenichi*; Korennov, S.*; Arai, Koji*; Noto, Hiroshi*; Onishi, Akira*; Kato, Kiyoshi*; Nakagawa, Tsuneo; et al.
AIP Conference Proceedings 769, p.561 - 564, 2005/05
A web-based search and plot system for nuclear reaction data has been developed, covering experimental data in EXFOR format and evaluated data in ENDF format. The system is implemented for Linux OS, with Perl and MySQL used for CGI scripts and the database manager, respectively. Two prototypes for experimental and evaluated data are presented.
Miyahara, H.*; Narita, N.*; Ikeda, Keiichi*; Kato, Y.*; Fujiki, K.*; Momose, Takumaro; Tasaki, Takashi; Kurihara, Osamu; Hayashi, Naomi
JNC TY8400 2001-002, 81 Pages, 2001/07
JNC-TY8400-2001-002.pdf:2.35MB
no abstracts in English
Sagisaka, Akito; *; Kondo, Kiminori*; Suzuki, Hajime*; Nagashima, Keisuke; Nagashima, Akira; Kawachi, Tetsuya; Kato, Yoshiaki; Takuma, Hiroshi
Applied Physics B, 70(4), p.549 - 554, 2000/04
Times Cited Count：7 Percentile：38.47(Optics)no abstracts in English
Sawaguchi, Takuma; Takeda, Seiji; Kozaki, Tamotsu*; Sekioka, Yasushi; Kato, Hiroyasu*; Kimura, Hideo
no journal, ,
no abstracts in English
Ishii, Katsunori; Suzuki, Masahiro; Yamamoto, Takuma; Kihara, Yoshiyuki; Matsusaka, Shuji*; Yasuda, Masatoshi*; Suna, Takayuki*; Kurita, Tsutomu; Kato, Yoshiyuki
no journal, ,
JAEA is developing simplified pelletizing MOX fuel fabrication process for fast breeder reactor. The final product of de-nitration, conversion and granulation process, are MOX fuel particles, of which diameter is hundres micrometer. These particles should have high flowability for easy handling in next process. The powder flowability is now evaluated by Carr's flowability index. In this oral presentation, the feasibility of powder flowability evaluation using vibrationg capillary method is investigated, employing ZrO particles of shich parameters are diameter and particle shape (shapes are varied by gronding particle edge). Screening small particles under about 100 micrometer contribute best the improvement of powder flowability, screening small particle under 50 micrometer in the second, and rounding particle shape in the third.
Ishii, Katsunori; Suzuki, Masahiro; Yamamoto, Takuma; Kihara, Yoshiyuki; Kurita, Tsutomu; Kato, Yoshiyuki; Yasuda, Masatoshi*; Matsusaka, Shuji*; Yoshimoto, Katsunobu
no journal, ,
Particle flowability test using a vibrating tube with a tapered end was carried out to evaluate the applicability of this method to the analysis of MOX particles for nuclear fuel pellet fabrication. In this experiment, zirconia particles were used as model particles, which are less than 850 micrometers in diameter. The sample particles were prepared by mixing the particles with different sizes. The experimental results showed that stable fowability evaluation is possible for particles larger than 45 micrometers and less than 850 micrometres, adjusting outlet diameter of tube and inclination angle of tube.
Kato, Yoshiyuki; Kurita, Tsutomu; Matsumoto, Masaki; Suzuki, Masahiro; Ishii, Katsunori; Yamamoto, Takuma; Kihara, Yoshiyuki; Yoshimoto, Katsunobu; Fujii, Kanichi
no journal, ,
An earlier accomplishment of FBR(fast breeder reactor) fuel cycle is the supreme subject from the point of view on the protection of environment by suppressing the green house effect as well as saving the oil. Microwave heating (MH) is employed as the MOX (mixed oxides U-Pu) production process in the main stream of FBR cycle. Thus, we are the optimization of MH method. We will describe the practical work of MOX fuel production which recycles the consumed nuclear fuel containing both U and Pu. The MH is employed to solidify the mixed solution by evaporating nitric acid and water. We call this processing de-nitration. The physical, mechanical, and chemical characteristics of the products are analyzed, being thereby discussed the contribution of the MH technology to the MOX fuel production. And, optimization of MH is discussed from the view point of design of MH oven, regulation of MH power, and combination with several auxiliary heating sources.
Ishii, Katsunori; Yamamoto, Takuma; Suzuki, Masahiro; Kihara, Yoshiyuki; Kato, Yoshiyuki; Kurita, Tsutomu; Yoshimoto, Katsunobu; Yoshimura, Tadahiro*
no journal, ,
To confirm the prospect of the simplified pellet production technology, JAEA is developing mass production technology for de-nitration conversion based on microwave heating. Base on the experimental result, the suitable processes for the mass production, are selected.
