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Journal Articles

Investigation of chemical state of uranium included in simulated waste glass

Nagai, Takayuki; Akiyama, Daisuke*; Kirishima, Akira*; Sato, Nobuaki*; Okamoto, Yoshihiro

2019-Nendo "Busshitsu, Debaisu Ryoiki Kyodo Kenkyu Kyoten" Oyobi "Hito, Kankyo To Busshitsu O Tsunagu Inobeshion Soshutsu Dainamikku, Araiansu" Kenkyu Seika, Katsudo Hokokusho (CD-ROM), P. 20191107_1, 2020/11

no abstracts in English

Journal Articles

The Chemistry of uranium (I); Basics and application

Sato, Nobuaki*; Kirishima, Akira*; Watanabe, Masayuki

Uran No Kagaku (I); Kiso To Oyo, 184 Pages, 2020/06

This particular book deals with fundamental items related with chemistry of Uranium and consists of basic section and practical section. In the basic section, inorganic and radiochemistry of Uranium was described. On the other hand, in the practical section, the process chemistry related with reprocessing of nuclear fuels and "debris" involved with Fukushima Daiichi Power Plant accident were described. This book is intended for use by scientists, engineers and students in the nuclear industry in their education and/or professional practice.

Journal Articles

Structural change of borosilicate glass by neutron irradiation

Nagai, Takayuki; Kobayashi, Hidekazu; Okamoto, Yoshihiro; Akiyama, Daisuke*; Sato, Nobuaki*; Uehara, Akihiro*; Fujii, Toshiyuki*; Sekimoto, Shun*

KURNS Progress Report 2018, P. 105, 2019/08

To understand this structural change of a borosilicate glass by a neutron irradiation in detail, the irradiation test was carried out in KUR in 2017FY. The glass structure was estimated by using Raman spectrometry in 2018FY. Comparing with the Raman spectra of glass samples before and after irradiation, it could be observed the change of peak height of Si-O bridging structure by the irradiation.

Journal Articles

Investigation of chemical state of uranium included in simulated waste glass

Nagai, Takayuki; Akiyama, Daisuke*; Sato, Nobuaki*; Okamoto, Yoshihiro

"Busshitsu, Debaisu Ryoiki Kyodo Kenkyu Kyoten" Oyobi "Hito, Kankyo To Busshitsu O Tsunagu Inobeshion Soshutsu Danamikku, Araiansu" Kenkyu Seika, Katsudo Hokokusho (Heisei-30-Nendo) (CD-ROM), P. 20181080_1, 2019/06

no abstracts in English

Journal Articles

Thermodynamic study of the complexation of humic acid by calorimetry

Kimuro, Shingo; Kirishima, Akira*; Kitatsuji, Yoshihiro; Miyakawa, Kazuya; Akiyama, Daisuke*; Sato, Nobuaki*

Journal of Chemical Thermodynamics, 132, p.352 - 362, 2019/05

 Times Cited Count:5 Percentile:27.25(Thermodynamics)

A combination of potentiometry and calorimetry was used for the determination of the thermodynamic quantities of complexation of generic and groundwater humic acid (HA), which was isolated from deep groundwater at Horonobe, Hokkaido, Japan, with copper (II) ions and uranyl (VI) ions. The apparent complexation constant of Horonobe HA was independent of the pH, whereas that of generic HA was dependent on the pH. This observation indicates that the polyelectrolyte effect of Horonobe HA is negligible because of its small molecular size. In addition, the effect of the heterogeneity of Horonobe HA was not significant. Moreover, the complexation enthalpy of Horonobe HA was consistent with that of homogeneous poly(acrylic acid), which means the complexation of Horonobe HA was not affected by the functional group heterogeneity. Consequently, the characteristic complexation mechanism of Horonobe HA was revealed based on the determined thermodynamic quantities.

Journal Articles

Evaluation of uranium chemical state in borosilicate glasses by using XAFS measurement

Nagai, Takayuki; Okamoto, Yoshihiro; Akiyama, Daisuke*; Sato, Nobuaki*

Photon Factory Activity Report 2018 (Internet), 2 Pages, 2019/00

no abstracts in English

Journal Articles

Characterization and thermodynamic study of humic acid in deep groundwater at Horonobe, Hokkaido, Japan

Kimuro, Shingo*; Kirishima, Akira*; Nagao, Seiya*; Saito, Takumi*; Amano, Yuki; Miyakawa, Kazuya; Akiyama, Daisuke*; Sato, Nobuaki*

Journal of Nuclear Science and Technology, 55(5), p.503 - 515, 2018/05

 Times Cited Count:3 Percentile:40.19(Nuclear Science & Technology)

no abstracts in English

Journal Articles

Investigation of chemical state of uranium included in glass

Nagai, Takayuki; Akiyama, Daisuke*; Sato, Nobuaki*

Busshitsu, Debaisu Ryoiki Kyodo Kenkyu Kyoten Kenkyu Seika Hokokusho (Heisei-29-Nendo) (CD-ROM), 1 Pages, 2018/04

no abstracts in English

Journal Articles

Evaluation of uranium chemical state in borosilicate glasses by using XAFS measurement

Nagai, Takayuki; Kobayashi, Hidekazu; Okamoto, Yoshihiro; Akiyama, Daisuke*; Sato, Nobuaki*

Photon Factory Activity Report 2017, 2 Pages, 2018/00

no abstracts in English

Journal Articles

Chemical behavior of platinum group compounds in the vitrification process condition

Nagai, Takayuki; Akiyama, Daisuke*; Sato, Nobuaki*; Sasage, Kenichi

Busshitsu, Debaisu Ryoiki Kyodo Kenkyu Kyoten Kenkyu Seika Hokokusho (Heisei-28-Nendo) (CD-ROM), 1 Pages, 2017/03

no abstracts in English

Journal Articles

Interaction of rare earth elements and components of the Horonobe deep groundwater

Kirishima, Akira*; Kuno, Atsushi*; Amamiya, Hiroki; Kubota, Takumi*; Kimuro, Shingo*; Amano, Yuki; Miyakawa, Kazuya; Iwatsuki, Teruki; Mizuno, Takashi; Sasaki, Takayuki*; et al.

Chemosphere, 168, p.798 - 806, 2017/02

 Times Cited Count:1 Percentile:92.28(Environmental Sciences)

For better understanding of the migration behavior of minor actinides (MA) in deep groundwater, the interaction of doped rare earth elements (REEs) and components in Horonobe deep groundwater was studied. Appx. 10 ppb of rare earth elements, i.e., Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm and Yb were doped to the sample groundwater collected from a packed sections in borehole drilled from 140 m depth experiment drift of Horonobe underground research laboratory (URL), Hokkaido, Japan. Then, that groundwater was sequentially filtrated by 0.2 micron pore filter, 10 kDa, 3 kDa and 1 kDa of nominal molecular weight limit (NMWL) ultrafilters by keeping inert condition. After that, the filtrate solutions were analyzed by ICP-MS to determine the concentrations of retained REEs at each filtration steps, while the used filters were analyzed by the neutron activation analysis (NAA) and TOF-SIMS element mapping to know the amount and chemical speciation of trapped fraction of the REEs on each filter. A remarkable relation between the retention ratios of REEs in the filtrate solutions and the ionic radius was observed, i.e., smaller rare earth element solves more in liquid phase under the Horonobe groundwater condition. NAA and TOF-SIMS analyses revealed that certain portions of REEs were trapped by 0.2 micron pore filters as rare earth phosphates which corresponded with the predicted predominant species by a chemical equilibrium calculation for the Horonobe groundwater condition, while small portions of colloidal REEs were trapped by 10 kDa and 3 kDa NMWL ultrafilters. The result suggested that phosphate anion plays an important role in the chemical behavior of REEs in saline (seawater based) groundwater, which could be referred for the prediction of migration behavior of trivalent actinide released from the repository of radioactive waste in far future.

Journal Articles

Beam commissioning of the linac for iBNCT

Naito, Fujio*; Anami, Shozo*; Ikegami, Kiyoshi*; Uota, Masahiko*; Ouchi, Toshikatsu*; Onishi, Takahiro*; Oba, Toshiyuki*; Obina, Takashi*; Kawamura, Masato*; Kumada, Hiroaki*; et al.

Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1244 - 1246, 2016/11

The proton linac installed in the Ibaraki Neutron Medical Research Center is used for production of the intense neutron flux for the Boron Neutron Capture Therapy (BNCT). The linac consists of the 3-MeV RFQ and the 8-MeV DTL. Design average beam current is 10mA. Target is made of Beryllium. First neutron production from the Beryllium target was observed at the end of 2015 with the low intensity beam as a demonstration. After the observation of neutron production, a lot of improvement s was carried out in order to increase the proton beam intensity for the real beam commissioning. The beam commissioning has been started on May 2016. The status of the commissioning is summarized in this report.

Journal Articles

Direct measurement of nanoscale lithium diffusion in solid battery materials using radioactive tracer of $$^{8}$$Li

Ishiyama, Hironobu*; Jeong, S.-C.*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Imai, Nobuaki*; Jung, H. S.*; Miyatake, Hiroari*; Oyaizu, Mitsuhiro*; Osa, Akihiko; Otokawa, Yoshinori; et al.

Nuclear Instruments and Methods in Physics Research B, 376, p.379 - 381, 2016/06

 Times Cited Count:6 Percentile:38.13(Instruments & Instrumentation)

Journal Articles

Investigation of ruthenium compounds in the vitrification process condition

Nagai, Takayuki; Sato, Nobuaki*; Sasage, Kenichi

Busshitsu, Debaisu Ryoiki Kyodo Kenkyu Kyoten Kenkyu Seika Hokokusho (Heisei-27-Nendo) (CD-ROM), 2 Pages, 2016/03

no abstracts in English

Journal Articles

Optical properties of tetravalent uranium complexes in non-aqueous media

Aoyagi, Noboru; Watanabe, Masayuki; Kirishima, Akira*; Sato, Nobuaki*; Kimura, Takaumi

Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1095 - 1098, 2015/02

 Times Cited Count:3 Percentile:63.46(Chemistry, Analytical)

Journal Articles

Nanoscale diffusion tracing by radioactive $$^{8}$$Li tracer

Ishiyama, Hironobu*; Jeong, S.-C.*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Imai, Nobuaki*; Miyatake, Hiroari*; Oyaizu, Mitsuhiro*; Katayama, Ichiro*; Osa, Akihiko; Otokawa, Yoshinori; et al.

Japanese Journal of Applied Physics, 53(11), p.110303_1 - 110303_4, 2014/11

 Times Cited Count:4 Percentile:82.21(Physics, Applied)

Journal Articles

Redox equilibrium of the UO$$_2^{2+}$$/UO$$_2^{+}$$ couple in Li$$_{2}$$MoO$$_{4}$$-Na$$_{2}$$MoO$$_{4}$$ eutectic melt at 550$$^{circ}$$C

Nagai, Takayuki; Uehara, Akihiro*; Fujii, Toshiyuki*; Sato, Nobuaki*; Kofuji, Hirohide; Myochin, Munetaka; Yamana, Hajimu*

Journal of Nuclear Materials, 454(1-3), p.159 - 163, 2014/11

 Times Cited Count:0 Percentile:100(Materials Science, Multidisciplinary)

The redox equilibrium of UO$$_2^{2+}$$/UO$$_2^{+}$$ couple was measured in Li$$_{2}$$MoO$$_{4}$$-Na$$_{2}$$MoO$$_{4}$$ eutectic melt at 550$$^{circ}$$C by cyclic voltammetry and absorption spectrophotometry. The standard redox potential of UO$$_2^{2+}$$/UO$$_2^{+}$$ couple was approximately evaluated by cyclic voltammetry. Further, the absorption spectrum and equilibrium potential were measured, repeatedly adding UO$$_2^{2+}$$ source material into the melt containing UO$$_2^{+}$$. From the correlation between the equilibrium potential of the melt and the concentration ratio [UO$$_2^{2+}$$]/[UO$$_2^{+}$$] spectrophotometrically evaluated, the standard redox potential of UO$$_2^{2+}$$/UO$$_2^{+}$$ couple was determined to be -0.847$$pm$$0.010 V vs. O$$_{2}$$/O$$^{2-}$$.

Journal Articles

Simultaneous saccharification and fermentation from ionic liquid-pretreated biomass using ionic liquid-tolerant yeast mutant

Ninomiya, Kazuaki*; Omote, Sayuri*; Sato, Katsuya; Narumi, Issey*; Shimizu, Nobuaki*

JAEA-Review 2013-059, JAEA Takasaki Annual Report 2012, P. 115, 2014/03

Journal Articles

Low temperature chlorination of Nd$$_{2}$$O$$_{3}$$ by mechanochemical method with CCl$$_{4}$$

Nagai, Takayuki; Kitawaki, Shinichi; Sato, Nobuaki*

Materials Sciences and Applications, 4(7), p.419 - 431, 2013/07

For a chlorinating method at low temperature, the possibility of chlorination of Nd$$_{2}$$O$$_{3}$$ by a mechanochemical reaction with CCl$$_{4}$$ was studied using a planetary ball mill. The mechanochemical experiments were conducted by changing the pot materials, milling time, molar ratio of CCl$$_{4}$$/Nd$$_{2}$$O$$_{3}$$, and revolution speed. As the results of obtained products by X-ray diffractometry and Raman spectroscopy, it was confirmed that the chlorination to NdOCl from Nd$$_{2}$$O$$_{3}$$ with CCl$$_{4}$$ was advanced at room temperature in a zirconia or tungsten pot with balls. We found that an extension of the milling time and an increase of the number of ball were effective to the chlorination to NdOCl and that tensile stress remained in the milled powder by using a planetary ball mill.

Journal Articles

Synthesis and investigation of uranyl molybdate UO$$_{2}$$MoO$$_{4}$$

Nagai, Takayuki; Sato, Nobuaki*; Kitawaki, Shinichi; Uehara, Akihiro*; Fujii, Toshiyuki*; Yamana, Hajimu*; Myochin, Munetaka

Journal of Nuclear Materials, 433(1-3), p.397 - 403, 2013/02

 Times Cited Count:7 Percentile:41.73(Materials Science, Multidisciplinary)

In order to examine easily synthetic conditions of uranyl molybdate, UO$$_{2}$$MoO$$_{4}$$, used for the reprocessing process study of spent nuclear oxide fuels in alkaline molybdate melts, the uranium molybdate compounds were produced from U$$_{3}$$O$$_{8}$$ powder and anhydrous MoO$$_{3}$$ reagent. The results of having investigated them in solid state by using X-ray diffractometry and Raman spectrometry, it was confirmed that UO$$_{2}$$MoO$$_{4}$$ could be synthesized by heating mixed powder of U$$_{3}$$O$$_{8}$$ and MoO$$_{3}$$ with stoichiometric mole ratio at 770$$^{circ}$$C for 4 h under air atmosphere. Moreover, adding this UO$$_{2}$$MoO$$_{4}$$ into Li$$_{2}$$MoO$$_{4}$$-Na$$_{2}$$MoO$$_{4}$$ eutectic melt, most of the dissolved uranium species in the melt were observed as hexa-valent uranyl ions by absorption spectrophotometry.

234 (Records 1-20 displayed on this page)