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JAEA Reports

Experimental verification of operational conditions for the 3rd glass melter in TVF

Asahi, Yoshimitsu; Fukuda, Shigeki; Shiramizu, Daiki; Miyata, Koshi; Tone, Masaya; Katsuoka, Nanako; Maeda, Yuta; Aoyama, Yusuke; Niitsuma, Koichi; Kobayashi, Hidekazu; et al.

JAEA-Technology 2024-024, 271 Pages, 2025/03

JAEA-Technology-2024-024.pdf:33.98MB
JAEA-Technology-2024-024-hyperlink.zip:31.96MB

A glass melter for the vitrification process of highly active liquid waste in the Tokai Reprocessing Plant, TVF's 3rd melter, was built, and the glass of 18 vitrified waste canisters in weight was melted and poured through a cold test operation. The molten glass surface was covered by a cold cap from feeding fiberglass cartridges saturated with non-radioactive simulant liquid waste as raw material, whose components are equivalent to actual waste. Differences in inherent characteristics of the thermal behavior between the 2nd and the 3rd melter due to the difference in design were considered to establish the procedure to control the new melter. The melter's condition was stabilized at a higher glass temperature and the cooling of 1 kW less in each of the two main electrodes, compared to the 2nd one. Under 39 kW joule heating of the main electrodes with 26 Nm3/h coolant flow rate, it showed the capability to finish heating the bottom furnace in 5 hours before pouring, 2 hours shorter than the 2nd melter. Measurements of the temperature distributions in molten glass and casing surface yielded data that is efficient for developing a simulation model. After Platinum Group Elements (PGE) concentration saturates in the molten glass, feeding raw material and discharging glass were suspended to examine a holding state, indicating PGE settling could retard. During the holding test, observation of the melting process of the cold cap declared that the surface was covered by a thin layer with almost non-fluidity. It will be a reason for choosing the no-slip condition of a fluid calculation, even in the hot-top condition. The investigation of PGE discharging behavior by analyzing the elemental composition of poured glass showed the accumulated PGE amount in the 3rd melter is small compared to the 2nd melter. Inspection of the melter inside after draining out concluded that there were neither significant residual glass nor refractory fragments.

Journal Articles

Development of a hybrid evaluation method for long-term structural soundness of nuclear reactor buildings using monitoring and damage imaging technologies; Nuclear energy science & technology and human resource development project

Maeda, Masaki*; Tanabe, Tadao*; Nishiwaki, Tomoya*; Aoki, Takayuki*; Dozaki, Koji*; Nishimura, Koshiro*; Fujii, Sho*; Ueno, Fumiyoshi; Tanaka, Akio*; Suzuki, Yusuke*; et al.

Transactions of the 27th International Conference on Structural Mechanics in Reactor Technology (SMiRT 27) (Internet), 10 Pages, 2024/03

Journal Articles

Production and separation of astatine isotopes in the $$^7$$Li + $$^{nat}$$Pb reaction

Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Maeda, Eita*; Watanabe, Shigeki; Hashimoto, Kazuyuki; Ishioka, Noriko; Makii, Hiroyuki; Toyoshima, Atsushi; Yamada, Norihiro*; et al.

Journal of Radioanalytical and Nuclear Chemistry, 304(3), p.1077 - 1083, 2015/06

 Times Cited Count:10 Percentile:60.46(Chemistry, Analytical)

Production cross sections of astatine isotopes $$^{207-211}$$At in the 29-57 MeV $$^7$$Li induced reaction with $$^{nat}$$Pb target have been measured by $$alpha$$- and $$gamma$$-ray spectrometry. Excitation functions of production cross sections have been compared with a statistical model calculation to study the reaction mechanism of $$^7$$Li + $$^{nat}$$Pb. Considerably small experimental cross sections of $$^{210}$$At and $$^{209}$$At compared with the calculation were clearly observed at incident energies higher than 44 MeV, indicating that the effects of breakup reaction play a role. A chemical separation of astatine from an irradiated lead target has been studied with a dry-distillation method. A complementary way to produce astatine isotopes has been developed.

Journal Articles

Extraction of astatine isotopes for development of radiopharmaceuticals using a $$^{211}$$Rn-$$^{211}$$At generator

Maeda, Eita*; Yokoyama, Akihiko*; Taniguchi, Takumi*; Washiyama, Koshin*; Nishinaka, Ichiro

Journal of Radioanalytical and Nuclear Chemistry, 303(2), p.1465 - 1468, 2015/02

 Times Cited Count:12 Percentile:67.00(Chemistry, Analytical)

The $$^{211}$$At isotope has gathered attention as a promising $$alpha$$-emitter for radionuclide therapy. We report the dependence of the distribution ratio of astatine on the concentration of HCl, and on the polarity of the organic solvent. The results will be useful for development of the $$^{211}$$Rn-$$^{211}$$At generator.

Journal Articles

Sorption of Eu(III) on granite; EPMA, LA-ICP-MS, batch and modeling studies

Fukushi, Keisuke*; Hasegawa, Yusuke*; Maeda, Koshi*; Aoi, Yusuke*; Tamura, Akihiro*; Arai, Shoji*; Yamamoto, Yuhei*; Aosai, Daisuke*; Mizuno, Takashi

Environmental Science & Technology, 47(22), p.12811 - 12818, 2013/11

 Times Cited Count:34 Percentile:62.33(Engineering, Environmental)

Eu(III) sorption on granite was examined by the combined microscopic and macroscopic approaches. Polished thin sections of the granite were reacted with solutions containing 10 $$mu$$M of Eu(III) and analyzed using EPMA and LA-ICP-MS. The Eu enrichment up to 6 wt.% was observed on most of the biotite grains. The Eu-enriched parts commonly lose K, which is the interlayer cation of biotite, indicating that the sorption mode is cation exchange in the interlayer. Batch Eu(III) sorption experiments on granite and biotite powders were conducted. The macroscopic sorption behavior of biotite was consistent with that of granite. The obtained sorption edges can be reproduced reasonably by the modeling considering single-site cation exchange reactions. Granite is complex mineral assemblages. However, the combined microscopic and macroscopic approaches revealed that elementary reactions by single phase can be representative for the bulk sorption reaction in complex mineral assemblages.

Journal Articles

Crystallization of a 2:2 complex of Granulocyte-Colony Stimulating Factor (GCSF) with the ligand-binding region of the GCSF receptor

Honjo, Eijiro; Tamada, Taro; Maeda, Yoshitake*; Koshiba, Takumi*; Matsukura, Yasuko*; Okamoto, Tomoyuki*; Ishibashi, Matsujiro*; Tokunaga, Masao*; Kuroki, Ryota

Acta Crystallographica Section F, 61(8), p.788 - 790, 2005/08

 Times Cited Count:7 Percentile:54.61(Biochemical Research Methods)

Granulocyte colony-stimulating factor (GCSF) receptor receives signals for regulating the proliferation and differentiation of the precursor cells of granulocytes. The complex composed of two GCSFs and two GCSF receptors was crystallized. The crystal of the complex was grown in 1.0 M sodium formate and 0.1 M sodium acetate (pH4.6). It belongs to the space group ${it P}$4$$_{1}$$2$$_{1}$$2 (or its enantiomorph ${it P}$4$$_{3}$$2$$_{1}$$2) with unit cell dimensions of ${it a}$ = ${it b}$ = 110.1 ${AA}$, ${it c}$ = 331.8 ${AA}$. However, the diffraction data from the crystal beyond 5 ${AA}$ resolution could not be collected. Since the heterogeneity of GCSF receptor seems to interrupt growth of good quality crystals, the GCSF receptor was fractionated by achromatography. Crystals of GCSF/fractionated GCSF receptor complex were grown as a new crystal form in 0.2 M ammonium phosphate. The new crystal diffracts beyond 3.0 ${AA}$ resolution and belongs to space group ${it P}$3$$_{1}$$21 (or its enantiomorph ${it P}$3$$_{2}$$21) with unit-cell parameters ${it a}$ = ${it b}$ = 134.8, ${it c}$ = 105.7 ${AA}$.

Journal Articles

The Effect of temperature, pressure, and sulfur content on viscosity of the Fe-FeS melt

Terasaki, Hidenori*; Kato, Takumi*; Urakawa, Satoru*; Funakoshi, Kenichi*; Suzuki, Akio*; Okada, Taku; Maeda, Makoto*; Sato, Jin*; Kubo, Tomoaki*; Kasai, Shizu*

Earth and Planetary Science Letters, 190(1-2), p.93 - 101, 2001/07

 Times Cited Count:56 Percentile:69.15(Geochemistry & Geophysics)

The Fe-FeS melt is thought to be the major candidate of the outer core material. Its viscosity is one of the most important physical properties to study the dynamics of the convection in the outer core. We performed the in situ viscosity measurement of the Fe-FeS melt under high pressure using X-ray radiography falling sphere method with a novel sample assembly. Viscosity was measures in the temperature, pressure, and compositional conditions of 1233-1923 K, 1.5-6.9 GPa, and Fe-Fe $$_{72}$$ S $$_{28}$$ (wt %), respectively. The viscosity coefficients obtained by 17 measurements change systematically in the range of 0.008-0.036 Pa s. An activation energy of the viscous flow, 30 kJ/mol, and the activation volume, 1.5 cm $$^{3}$$ /mol, are determined as the temperature and pressure dependence, and the viscosity of the Fe $$_{72}$$ S $$_{28}$$ melt is found to be smaller than that of the Fe melt by 15 %. These tendencies can be well correlated with the structural variation of the Fe-FeS melt.

Oral presentation

Production of alpha-emitting radioisotopes using the cyclotron facilities at Osaka University and JAEA Takasaki, and the Tandem accelerator at Tokai, JAEA

Washiyama, Koshin*; Amano, Ryohei*; Maeda, Eita*; Yokoyama, Akihiko*; Nishinaka, Ichiro; Takahashi, Naruto*; Shinohara, Atsushi*; Watanabe, Shigeki; Ishioka, Noriko

no journal, , 

In order to use of an alpha emitter for targeted alpha therapy, we have started the production and the utilization of $$^{211}$$At using 30 MeV $$^4$$He particle in the $$^{209}$$Bi($$^4$$He, 2n)$$^{211}$$At nuclear reaction at cyclotron facilities of Osaka University and JAEA Takasaki. In addition to that, we have been developing a $$^{211}$$Rn/$$^{211}$$At generator to expand the availability of $$^{211}$$At to wide range of populations far away from cyclotron facilities. The results of studies on the At-chemistry for clinical use and on the development of the $$^{211}$$Rn/$$^{211}$$At generator will be presented. And a review of current status of targeted alpha therapy in Japan will be also introduced.

Oral presentation

Development of in-situ sorption experiment system in underground research laboratory

Hasegawa, Yusuke*; Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi; Maeda, Koshi*; Fukushi, Keisuke*

no journal, , 

no abstracts in English

Oral presentation

Surface complexation modeling for Eu adsorption on granite

Maeda, Koshi*; Hasegawa, Yusuke*; Fukushi, Keisuke*; Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi

no journal, , 

no abstracts in English

Oral presentation

Determination of the partition coefficient (Kd) under in-situ groundwater conditions using a hydrochemical monitoring system

Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi; Fukushi, Keisuke*; Hasegawa, Yusuke*; Maeda, Koshi*

no journal, , 

no abstracts in English

Oral presentation

Modeling and batch experiment for understanding of Eu(III) sorption on granite

Maeda, Koshi*; Fukushi, Keisuke*; Hasegawa, Yusuke*; Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi

no journal, , 

no abstracts in English

Oral presentation

Identification and characterization of phase governing Eu(III) uptake in granite by microscopic observations

Hasegawa, Yusuke*; Fukushi, Keisuke*; Maeda, Koshi*; Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi

no journal, , 

no abstracts in English

Oral presentation

Nuclear and radiochemical study of production and utilization of radioactive astatine isotopes in the Li + $$^{nat}$$Pb reaction

Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Maeda, Eita*; Yamada, Norihiro*; Makii, Hiroyuki; Watanabe, Shigeki; Ishioka, Noriko; Hashimoto, Kazuyuki

no journal, , 

Oral presentation

Nuclear and radiochemical study of production and utilization of radioactive astatine isotopes in the Li+$$^{nat}$$Pb reaction; Aim at the new cancer medical treatment by $$alpha$$-emitting radioisotopes

Nishinaka, Ichiro; Makii, Hiroyuki; Toyoshima, Atsushi; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Maeda, Eita*; Yamada, Norihiro*; Taniguchi, Takumi*; Watanabe, Shigeki; et al.

no journal, , 

no abstracts in English

Oral presentation

Production and utilization of radioactive astatine isotopes in the $$^7$$Li + $$^{nat}$$Pb reaction

Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Maeda, Eita*; Yamada, Norihiro*; Makii, Hiroyuki; Toyoshima, Atsushi; Watanabe, Shigeki; Ishioka, Noriko; et al.

no journal, , 

Production cross sections of astatine in 29-57 MeV $$^7$$Li + $$^{rm nat}$$Pb have been measured by $$alpha$$- and $$gamma$$-ray spectrometry. Excitation functions of production cross sections have been compared with a statistical model calculation to study the reaction mechanism of the $$^7$$Li + $$^{rm nat}$$Pb reaction. It indicates that the breakup of $$^7$$Li plays a rule in the $$^7$$Li + $$^{rm nat}$$Pb reaction. Besides, we have developed a dry-distillation method which separates carrier-free astatine from an irradiated lead target.

Oral presentation

Production of astatine radioisotopes in the $$^7$$Li+$$^{nat}$$Pb reaction and simple chemical separation of astatine

Nishinaka, Ichiro; Yokoyama, Akihiko*; Washiyama, Koshin*; Amano, Ryohei*; Ri, Keiko*; Yamada, Norihiro*; Ishiguro, Rika*; Maeda, Eita*; Makii, Hiroyuki; Hashimoto, Kazuyuki; et al.

no journal, , 

We have started to study production and utilization of an $$alpha$$ radioactive nuclide $$^{211}$$At which is a prospective candidate for targeted alpha radiotherapy. We determined production cross sections of astatine radioisotopes in the reaction of 29-48 MeV $$^7$$Li+$$^{nat}$$Pb by $$alpha$$-ray and $$gamma$$-ray spectrometry at the tandem accelerator of JAEA-Tokai. Besides, we developed a simple dry-chemical method for separation of astatine.

Oral presentation

Production of $$^{211}$$At for alpha radiotherapy via $$^{209}$$Bi($$^7$$Li,5n)$$^{211}$$Rn

Nishinaka, Ichiro; Washiyama, Koshin*; Yokoyama, Akihiko*; Maeda, Eita*; Hashimoto, Kazuyuki; Makii, Hiroyuki

no journal, , 

A $$^{211}$$Rn/$$^{211}$$At generator has been proposed to supply a radiotracer $$^{211}$$At with a half-life (T$$_{1/2}$$ = 7.2 h) for medical applications. To establish a technology of the $$^{211}$$Rn/$$^{211}$$At generator, $$^{211}$$Rn (T$$_{1/2}$$ = 14.7 h) has to be produced through the $$^{209}$$Bi($$^7$$Li, 5n)$$^{211}$$Rn reaction without melting bismuth metal targets due to heat produced by the irradiation of 60 MeV $$^7$$Li ion beams. In this work, we have studied the effects of a He gas cooling system of an irradiation chamber constructed for the production of $$^{211}$$Rn. Irradiations were carried out at the JAEA tandem accelerator using the irradiation chamber equipped with the He gas cooling system. The results show that the He gas effectively cools the targets and the cooling efficiency is nearly independent of the pressure ($$>$$ 1 kPa) and the flow rate ($$sim$$20 L/min) of the He gas.

Oral presentation

Identification and characterization of phase governing Eu(III) uptake in granite by microscopic observations

Hasegawa, Yusuke*; Fukushi, Keisuke*; Maeda, Koshi*; Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi

no journal, , 

Oral presentation

Modeling Eu(III) sorption on granite

Maeda, Koshi*; Fukushi, Keisuke*; Hasegawa, Yusuke*; Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi

no journal, , 

24 (Records 1-20 displayed on this page)