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Taniguchi, Takumi; Matsumoto, Saori; Hiraki, Yoshihisa; Sato, Junya; Fujita, Hideki*; Kaneda, Yoshihisa*; Kuroki, Ryoichiro; Osugi, Takeshi
JAEA-Review 2024-059, 20 Pages, 2025/03
JAEA-Review-2024-059.pdf:1.0MB
The basic performance required for solidifying waste into cement, such as fluidity before curing and strength after curing, is expected to be affected by the chemical effects of substances and components contained in the waste. The fluidity before curing and the strength properties after curing are greatly influenced by the curing speed of the cement. We investigated existing knowledge with a focus on chemical substances that affect the curing speed of cement. In this report, chemical substances that affect fluidity are broadly classified into inorganic substances such as (1) anion species, (2) metal elements such as heavy metals, (3) inorganic compounds as cement admixtures, and (4) organic compounds as cement admixtures. Based on the investigation, we actually added chemicals and measured the setting time. As a result, it was found that there are multiple mechanisms contributing to accelerated hardening. We investigated chemical substances that inhibit the curing reaction of cement, and were able to compile information to consider ingredients that are contraindicated in cement curing.
and Eu(As
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)Onuki, Yoshichika*; Karube, Kosuke*; Aoki, Dai*; Nakamura, Ai*; Homma, Yoshiya*; Matsuda, Tatsuma*; Haga, Yoshinori; Takeuchi, Tetsuya*
Journal of the Physical Society of Japan, 92(11), p.114703_1 - 114703_12, 2023/11
Times Cited Count：1 Percentile：0.00(Physics, Multidisciplinary)
CMiyazawa, Takeshi; Kikuchi, Yuta*; Ando, Masami*; Yu, J.-H.*; Yabuuchi, Kiyohiro*; Nozawa, Takashi*; Tanigawa, Hiroyasu*; Nogami, Shuhei*; Hasegawa, Akira*
Journal of Nuclear Materials, 575, p.154239_1 - 154239_11, 2023/03
Times Cited Count：4 Percentile：79.63(Materials Science, Multidisciplinary)Nugraha, E. D.*; Hosoda, Masahiro*; Kusdiana*; Untara*; Mellawati, J.*; Nurokhim*; Tamakuma, Yuki*; Ikram, A.*; Syaifudin, M.*; Yamada, Ryohei; et al.
Scientific Reports (Internet), 11(1), p.14578_1 - 14578_16, 2021/07
Times Cited Count：25 Percentile：82.15(Multidisciplinary Sciences)Mamuju is one of the regions in Indonesia which retains natural conditions but has relatively high exposure to natural radiation. The goals of the present study were to characterize exposure of the entire Mamuju region as a high natural background radiation area (HNBRA) and to assess the existing exposure as a means for radiation protection of the public and the environment. A cross-sectional study method was used with cluster sampling areas by measuring all parameters that contribute to external and internal radiation exposures. It was determined that Mamuju was a unique HNBRA with the annual effective dose between 17 and 115 mSv, with an average of 32 mSv. The lifetime cumulative dose calculation suggested that Mamuju residents could receive as much as 2.2 Sv on average which is much higher than the average dose of atomic bomb survivors for which risks of cancer and non-cancer diseases are demonstrated. The study results are new scientific data allowing better understanding of health effects related to chronic low-dose-rate radiation exposure and they can be used as the main input in a future epidemiology study.
Sasaki, Yuji; Nakase, Masahiko*
Petorotekku, 43(11), p.782 - 787, 2020/11
As analog compounds of DGA (diglycolamide), MIDOA(methylimino-diacetamide) and TDGA(thia-diglycolammide) are used for the extractants of platinum group metals. These extractants can be extracted noble metals and oxyanions, which followed by HSAB theory. The high concentration of these metals can be also extracted by these compounds. The research of metal-complex structures gives the information on the ability and role for complex-formation, which will be useful for the development of novel extractants.
Suzuki, Tomoya*; Ogata, Takeshi*; Tanaka, Mikiya*; Kobayashi, Toru; Shiwaku, Hideaki; Yaita, Tsuyoshi; Narita, Hirokazu*
Analytical Sciences, 35(12), p.1353 - 1360, 2019/12
Times Cited Count：5 Percentile：18.63(Chemistry, Analytical)no abstracts in English
Kakihana, Masashi*; Nishimura, Kengo*; Takeuchi, Tetsuya*; Haga, Yoshinori; Harima, Hisatomo*; Hedo, Masato*; Nakama, Takao*; Onuki, Yoshichika*
Journal of the Physical Society of Japan, 88(4), p.044712_1 - 044712_11, 2019/04
Times Cited Count：4 Percentile：32.98(Physics, Multidisciplinary)Futakawa, Masatoshi
Proceedings of 13th International Symposium on Advanced Science and Technology in Experimental Mechanics (13th ISEM'18) (USB Flash Drive), 6 Pages, 2018/10
Issues on the engineering technologies relating to high-power spallation neutron sources with liquid metals are introduced. The present status on research activities and results was reviewed.
Itami, Toshio*; Saito, Junichi; Ara, Kuniaki
Metals, 5(3), p.1212 - 1240, 2015/09
Times Cited Count：2 Percentile：3.38(Materials Science, Multidisciplinary)A new kind of suspension liquid was developed by dispersing Ti nanoparticles (10 nm) in liquid Na, which was then determined by TEM (transmission electron microscopy) analysis. The volume fraction was estimated to be 0.0088 from the analyzed Ti concentration (2 at.%) and the densities of Ti and Na. This suspension liquid, Liquid Sodium containing nanoparticles of titanium (LSnanop), shows, despite only a small addition of Ti nanoparticles, many striking features, namely a negative deviation of 3.9% from the ideal solution for the atomic volume, an increase of 17% in surface tension, a decrease of 11% for the reaction heat to water, and the suppression of chemical reactivity to water and oxygen. The decrease in reaction heat to water seems to be derived from the existence of excess cohesive energy of LSnanop. The excess cohesive energy was discussed based on simple theoretical analyses, with particular emphasis on the screening effect. The suppression of reactivity is discussed with the relation to the decrease of heat of reaction to water or the excess cohesive energy, surface tension, the action as a plug of Ti oxide, negative adsorption on the surface of LSnanop, and percolation.
Shimada, Michiya; Hirooka, Yoshihiko*
Nuclear Fusion, 54(12), p.122002_1 - 122002_7, 2014/12
Times Cited Count：40 Percentile：85.99(Physics, Fluids & Plasmas)Tungsten is considered to be the most promising material for divertor in a fusion reactor. Tungsten divertor can withstand the heat loads of ITER, but the heat loads of DEMO divertor is a challenge. Pulsive heat loads as those associated with disruption could melt tungsten targets. The surface would not be flat after subsequent resolidification, which would significantly deteriorate its heat handling capability. Furthermore, DBTT of tungsten is rather high: 
400C, which would become even higher after neutron irradiation, possibly resulting in cracks in tungsten. Our proposal is to use liquid metal for the divertor target material and actively circulate it with 
force. A simplified analysis of mhd equation in a cylindrical geometry suggests that the engineering requirement is modest. This analysis suggests that this new divertor concept merits further investigation.
edge of Mn
GaCTakahashi, Manabu*; Igarashi, Junichi
Physical Review B, 67(24), p.245104_1 - 245104_5, 2003/06
Times Cited Count：23 Percentile：70.01(Materials Science, Multidisciplinary)We theoretically investigate the origin of the X-ray magnetic circular dichroism (XMCD) spectra at the K edge of Mn and Ga in the ferromagnetic phase of MnGaC on the basis of an ab initio calculation. Taking account of the spin-orbit interaction in the LDA scheme, we obtain the XMCD spectra in excellent agreement with the recent experiment. We have analyzed the origin of each structure, and thus elucidated the mechanism of inducing the orbital polarization in the p symmetric states. We also discuss a simple sum rule connecting the XMCD spectra with the orbital moment in the p symmetric states.
Tamada, Masao; Kasai, Noboru; Seko, Noriaki; Hasegawa, Shin; Kawabata, Yukiya*; Onuma, Kenji*; Takeda, Hayato*; Katakai, Akio; Sugo, Takanobu
JAERI-Tech 2001-065, 39 Pages, 2001/11
JAERI-Tech-2001-065.pdf:5.24MB
Positioning and monitoring system for marine component in recovery equipment of significant metals from seawater by using adsorbent was designed and assembled to avoid unexpected accidents. This system which was set on float part of the marine component obtains the position data by means of GPS satellites and send them to Takasaki and Mutsu establishments through satellite communication. As characteristic test for 20 days in the real sea, 256 data were obtained every 2 hours. The wrong data was eight and the positioning accuracy was 200.7m. To improve these characteristics, two new functions were added to the present firmware. These are to raise positioning resolutions in longitude and latitude from 0.001 to 0.00001 degree and to average remaining three data of positioning after maximum and minimum data were removed from continuous five times positioning. The improved system shows no wrong datum, average positioning of 6.74m. This performance is enough to prevent marine equipment from its drifting accident.
Takeda, Hayato*; Onuma, Kenji*; Tamada, Masao; Kasai, Noboru; Katakai, Akio; Hasegawa, Shin; Seko, Noriaki; Kawabata, Yukiya*; Sugo, Takanobu
JAERI-Tech 2001-062, 66 Pages, 2001/10
Real sea experiment for the recovery of significant metals such as uranium and vanadium has been carried out at the offing of Mutsu establishment to evaluate the adsorption performance of adsorbent synthesized by radiation-induced graft-polymerization. After elution of uranium and vanadium from the adsorbent, their metals were adsorbed onto the conventional chelate resin. This chelate resin in a plastic column was further put in a cylindrical stainless transport container. The container was transported to the facility for separation and purification by a truck for the exclusive loading. The maximum concentration is 60 Bq/g when the uranium is adsorbed on the chelate resin. Transportation of recovered metals can be treated as general substance since these amount and concentration are out of legal control. However, the recovered metals were transported in conformity to L type transportation as a voluntary regulation. The strength analysis of the container was equal to the safety level of IP-2 type which is higher transportation grade than L type .
Sakamura, Yoshiharu*; Shirai, Osamu; Iwai, Takashi; Suzuki, Yasufumi
Journal of Alloys and Compounds, 321(1), p.76 - 83, 2001/05
Times Cited Count：59 Percentile：89.28(Chemistry, Physical)no abstracts in English
Iwase, Akihiro
Dai-11-Kai Ryushisen No Sentanteki Oyo Gijutsu Ni Kansuru Shimpojiumu (BEAMS 2000) Hobunshu, p.123 - 126, 2000/00
no abstracts in English
Morimoto, Yoshiki*; Kato, Sayuri*; Toda, Naohiro*; Katayama, Yoshinori; Tsuji, Kazuhiko*; Yaoita, Kenichi*; Shimomura, Osamu
Review of High Pressure Science and Technology, 7, p.245 - 247, 1998/03
X-ray diffraction for liquid Rb and liquid Na has been measured under pressure up to 6 GPa using synchrotron radiation. Volume dependences of static structure factor 
and pair distribution function 
were obtained to the volume range 
of 0.52 for liquid Rb and 
of 0.73 for liquid Na to investigate the effect of the electronic change on the structure of liquid metals. With increasing pressure, the peaks of of both liquid Rb and liquid Na shift towards higher 
, and the heights of the first peak increase. Theses volume dependences of the structural data are compared with those for other metals under pressure and expanded fluids.
; Chihara, Junzo
Molecular Simulation, 16, p.31 - 46, 1996/00
Times Cited Count：5 Percentile：20.88(Chemistry, Physical)no abstracts in English
9, 1994, Tokai, JapanJAERI-Conf 94-004, 187 Pages, 1994/11
no abstracts in English
Naramoto, Hiroshi
Isotope News, (474), p.28 - 29, 1993/12
no abstracts in English
Iwase, Akihiro; Iwata, Tadao; Nihira, Takeshi*
Nihon Butsuri Gakkai-Shi, 48(4), p.274 - 278, 1993/04
no abstracts in English
