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Mo adsorption; Utilizing spray-dried mesoporous alumina for clinical-grade generator developmentAlowasheeir, A.*; Eguchi, Miharu*; Fujita, Yoshitaka; Tsuchiya, Kunihiko; Wakabayashi, Ryutaro*; Kimura, Tatsuo*; Ariga, Katsuhiko*; Hatano, Kentaro*; Fukumitsu, Nobuyoshi*; Yamauchi, Yusuke*
Bulletin of the Chemical Society of Japan, 97(10), p.uoae099_1 - uoae099_7, 2024/10
Times Cited Count：4 Percentile：64.85(Chemistry, Multidisciplinary)no abstracts in English
Tc separation/concentration technology from Mo by (n, 
) method, 2Fujita, Yoshitaka; Hu, X.*; Yang, Y.*; Kitagawa, Taiga*; Fujihara, Yasuyuki*; Yoshinaga, Hisao*; Hori, Junichi*; Do, T. M. D.*; Suzuki, Tatsuya*; Suematsu, Hisayuki*; et al.
KURNS Progress Report 2023, P. 122, 2024/07
no abstracts in English
Mo/
Tc generators using the (n,) method (Thesis)Fujita, Yoshitaka
JAEA-Review 2023-010, 108 Pages, 2023/08
JAEA-Review-2023-010.pdf:6.62MB
Tc (technetium-99m) is the most widely used radioisotope in radiopharmaceutical and is decayed from the parent nuclide Mo (molybdenum-99). Most of Mo is generated as one of the fission products of uranium, but recently, from the viewpoint of nuclear security and nuclear nonproliferation, a uranium-free Mo production method is desired. One such method is the (n,) method, in which 
Mo is irradiated by neutrons. However, since the specific activity of Mo produced by this method is extremely low, it is necessary to improve the Mo adsorption and Tc elution property of alumina (Al
O
), which is used as a Mo adsorbent, to apply this method to the Mo/Tc generator, a device for separation and concentration of Tc from Mo. Therefore, the objective of this thesis is to elucidate the parameters effective for improving the performance of alumina for the practical use of the Mo/Tc generator using the (n,) method, and to contribute to the development of alumina columns that may be applicable to low specific activity Mo. In this study, alumina with different starting materials was prepared and its applicability as Mo adsorbent for Mo/Tc generator was evaluated. The effects of crystal structure and specific surface area of alumina on Mo adsorption properties were clarified, and the Mo adsorption mechanism was elucidated based on the results of surface analysis of alumina. In addition, Tc elution properties and Tc solution quality were evaluated using MoO irradiated in the Kyoto University Research Reactor (KUR), and a new column shape with potential application to generators was proposed based on the experiment results of alumina columns designed for current generators.
Fujita, Yoshitaka; Niizeki, Tomotake*; Fukumitsu, Nobuyoshi*; Ariga, Katsuhiko*; Yamauchi, Yusuke*; Malgras, V.*; Kaneti, Y. V.*; Liu, C.-H.*; Hatano, Kentaro*; Suematsu, Hisayuki*; et al.
Bulletin of the Chemical Society of Japan, 95(1), p.129 - 137, 2022/01
Times Cited Count：10 Percentile：60.41(Chemistry, Multidisciplinary)In this work, the mechanisms responsible for the adsorption of molybdate ions on alumina are investigated using in-depth surface analyses carried out on alumina specimens immersed in solutions containing different molybdate ions at different pH values. The obtained results reveal that when alumina is immersed in an acidic solution containing molybdate ions, the hydroxyl groups present on the surface are removed to generate positively charged sites, and molybdate ions (MoO
or AlMo
O
H
) are adsorbed by electrostatic interaction. Alumina dissolves slightly in an acidic solution to form AlMoOH, which is more easily desorbed than MoO. Furthermore, the enhancement in the Mo adsorption or desorption property may be achieved by enriching the surface of the alumina adsorbent with many -OH groups and optimizing Mo solution to adsorb molybdate ions on alumina as MoO ions. These findings will assist researchers in engineering more efficient and stable alumina-based adsorbents for molybdenum adsorption used in medical radioisotope (Mo/Tc) generators.
Mo adsorption and Tc elution with alumina columnsFujita, Yoshitaka; Seki, Misaki; Sano, Tadafumi*; Fujihara, Yasuyuki*; Suzuki, Tatsuya*; Yoshinaga, Hisao*; Hori, Junichi*; Suematsu, Hisayuki*; Tsuchiya, Kunihiko
Journal of Physics; Conference Series, 2155, p.012018_1 - 012018_6, 2022/01
Technetium-99m (Tc), the daughter nuclide of Molybdenum-99 (Mo), is the most commonly used radioisotope in radiopharmaceuticals. The research and development (R&D) for the production of Mo by the neutron activation method ((n, ) method) has been carried out from viewpoints of no-proliferation and nuclear security, etc. Since the specific activity of Mo produced by the (n, ) method is extremely low, developing AlO with a large Mo adsorption capacity is necessary to adapt (n, )Mo to the generator. In this study, three kinds of AlO specimens with different raw materials were prepared and compared their adaptability to generators by static and dynamic adsorption. MoO pellet pieces (1.5g) were irradiated with 5 MW for 20 min in the Kyoto University Research Reactor (KUR). Irradiated MoO pellet pieces were dissolved in 6M-NaOH aq. In dynamic adsorption, 1 g of AlO was filled into a PFA tube (
1.59 mm). The Mo adsorption capacity of AlO specimens under dynamic condition was slightly reduced compared to that under static condition. The Tc elution rate was about 100% at 1.5 mL of milking in dynamic adsorption, while it was around 56-87% in static adsorption. The Mo/Tc ratio of dynamic condition was greatly reduced compared to that of static condition. Therefore, the Tc elution property is greatly affected by the method of adsorbing Mo, e.g., the column shape, the linear flow rate, etc.
Segawa, Tomoomi; Kawaguchi, Koichi; Ishii, Katsunori; Suzuki, Masahiro; Tachihara, Joji; Takato, Kiyoto; Okita, Takatoshi; Satone, Hiroshi*; Suzuki, Michitaka*
Mechanical Engineering Journal (Internet), 8(3), p.21-00022_1 - 21-00022_9, 2021/06
To reduce the hold-up of the nuclear fuel materials in the glove box and the external exposure dose, the technology of the MOX powder adhesion prevention by the nanoparticle coating to the acrylic panels of the glove box has been developed. The surface analysis by means of atomic force microscopy (AFM) showed that the acrylic test piece surface coated with nanoparticles had a higher root mean square roughness value than that non-coated with nanoparticles. Due to the formation of nano-sized tiny rugged surface, the nanoparticle coating reduced the minimum adhesion force between the UO particles and the acrylic test piece surface with the smallest particle size of about 5 
m where desorption was observed, by about one-tenth. Moreover, the nanoparticle coating reduced the amount of the MOX powder adhering to the acrylic test piece to about one-tenth. In this study, it was found that applying the nanoparticle coating to the acrylic panels of glove box can prevent the adhesion of nuclear fuel materials. This method is effective for reducing the hold-up of the nuclear fuel materials in the glove box, the external exposure dose and improving the visibility of the acrylic panels.
Mo-adsorption/Tc-elution properties of alumina with different surface structuresFujita, Yoshitaka; Seki, Misaki; Sano, Tadafumi*; Fujihara, Yasuyuki*; Kitagawa, Tomoya*; Matsukura, Minoru*; Hori, Junichi*; Suzuki, Tatsuya*; Tsuchiya, Kunihiko
Journal of Radioanalytical and Nuclear Chemistry, 327(3), p.1355 - 1363, 2021/03
Times Cited Count：4 Percentile：39.96(Chemistry, Analytical)We prepared three types of AlO with different surface structures and investigated Mo-adsorption/Tc-elution properties using [Mo]MoO that was irradiated in the Kyoto University Research Reactor. AlO adsorbed [Mo]molybdate ions in solutions at different pH; the lower was the pH, the higher was the Mo-adsorption capacity of AlO. The Tc-elution properties of molybdate ion adsorbed AlO were elucidated by flowing saline. Consequently, it was suggested that Mo-adsorption/desorption properties are affected by the specific surface of AlO and Tc-elution properties are affected by the crystal structure of AlO.
Meigo, Shinichiro; Takei, Hayanori; Matsuda, Hiroki; Yuri, Yosuke*; Yuyama, Takahiro*
Proceedings of 16th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.515 - 519, 2019/07
no abstracts in English
Saptiama, I.*; Kaneti, Y. V.*; Yuliarto, B.*; Kumada, Hiroaki*; Tsuchiya, Kunihiko; Fujita, Yoshitaka; Malgras, V.*; Fukumitsu, Nobuyoshi*; Sakae, Takeji*; Hatano, Kentaro*; et al.
Chemistry; A European Journal, 25(18), p.4843 - 4855, 2019/03
Times Cited Count：17 Percentile：49.91(Chemistry, Multidisciplinary)The effective utilization of various biomolecules for creating a series of mesoporous boehmite (-AlOOH) and gamma-alumina (-AlO) nanosheets with unique hierarchical multilayered structures is demonstrated. The nature and concentration of the biomolecules strongly influence the degree of the crystallinity, the morphology, and the textural properties of the resulting -AlOOH and -AlO nanosheets, allowing for easy tuning. The hierarchical -AlOOH and -AlO multilayered nanosheets synthesized by using biomolecules exhibit enhanced crystallinity, improved particle separation, and well-defined multilayered structures compared to those obtained without biomolecules. More impressively, these -AlOOH and -AlO nanosheets possess high surface areas up to 425 and 371 m
/g, respectively, due to their mesoporous nature and hierarchical multilayered structure. When employed for molybdenum adsorption toward medical radioisotope production, the hierarchical -AlO multilayered nanosheets exhibit Mo adsorption capacities of 33.1
40.8mg-Mo/g.
Fukumitsu, Nobuyoshi*; Yamauchi, Yusuke*; Saptiama, I.*; Ariga, Katsuhiko*; Hatano, Kentaro*; Kumada, Hiroaki*; Fujita, Yoshitaka; Tsuchiya, Kunihiko
Isotope News, (760), p.15 - 18, 2018/12
no abstracts in English
Meigo, Shinichiro; Takei, Hayanori; Matsuda, Hiroki; Yuri, Yosuke*; Yuyama, Takahiro*
Proceedings of 15th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1035 - 1039, 2018/08
no abstracts in English
Meigo, Shinichiro
Proceedings of 61st ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams (HB 2018) (Internet), p.99 - 103, 2018/07
As the increase of beam power, beam instruments play an essential role in the Hadron accelerator facility. In J-PARC, the pitting erosion on the mercury target vessel for the spallation neutron source is one of a pivotal issue to operate with the high power of the beam operation. Since the erosion is proportional to the 4th power of the beam current density, the minimization of the peak current density is required. To achieve low current density, the beam-flattening system by nonlinear beam optics in J-PARC, by which the peak density was successfully reduced by 30% than the density with the conventional case optics. Since the ADS requires a very powerful accelerator with the beam power such as 30 MW, a robust beam profile monitor is required, especially for the observation of the beam status on the target continuously. A candidate material for the beam monitor was developed by using heavy-ion of Ar beam to give the damage efficiently.
Meigo, Shinichiro; Matsuda, Hiroki; Takei, Hayanori
Proceedings of 6th International Beam Instrumentation Conference (IBIC 2017) (Internet), p.373 - 376, 2018/03
no abstracts in English
Saptiama, I.*; Kaneti, Y. V.*; Suzuki, Yumi*; Suzuki, Yoshitaka; Tsuchiya, Kunihiko; Sakae, Takeji*; Takai, Kimiko*; Fukumitsu, Nobuyoshi*; Alothman, Z. A.*; Hossain, M. S. A.*; et al.
Bulletin of the Chemical Society of Japan, 90(10), p.1174 - 1179, 2017/10
Times Cited Count：45 Percentile：76.91(Chemistry, Multidisciplinary)no abstracts in English
Kinsho, Michikazu; Saito, Yoshio*; Kabeya, Zenzaburo*; Ogiwara, Norio
Vacuum, 81(6), p.808 - 811, 2007/02
Times Cited Count：7 Percentile：29.39(Materials Science, Multidisciplinary)It was success to develop alumina ceramics vacuum ducts for the 3GeV-RCS of J-PARC at JAERI. There are two types of alumina ceramics vacuum ducts needed, one being 1.5m-long duct with a circular cross section of 378 mm inner diamater for use in the quadrupole magnet, the other being 3.5m-long and bending 15 degrees, with a race-track cross section for use in the dipole magnet. These ducts could be manufactured by joining several duct segments of 0.8 m in length by brazing. The alumina ceramics ducts have copper stripes on the outside surface of the ducts to reduce the duct impedance. The radio-frequency shield is designed as a high frequency pass filter, where eddy currents cannot be generated. In this shield one end of each strope is connected to a titanium flange with a capacitor to interrupt the eddy current loop. With this, the impedance of the duct with the radio-frequency shield was reduced within an allowable desgin limit. In order to reduce emission of secondary electrons when protons or electrons strike the surface, TiN film is coated on the inside surface of the ducts.
Nishi, Hiroshi
Fusion Engineering and Design, 81(1-7), p.269 - 274, 2006/02
Times Cited Count：5 Percentile：35.34(Nuclear Science & Technology)Tensile strength of the diffusion bonded joint was as large as that of Alumina dispersion-strengthened copper (DS Cu), however, the Charpy absorbed energy of the joint was considerably lower than that of DS Cu. Instrumented Charpy impact test and slow-bend Charpy test of diffusion bonded joints were performed to clarify the degradation of Charpy absorbed energy. Elasto-plastic analyses were also carried out in order to study the deformation behavior of the tensile and V-notched specimens for joints. As the results, the fracture behaviors of the impact and slow-bend tests were almost the same. Elasto-plastic analyses showed that the maximum strain occurred at the DS Cu apart from the interface for tensile specimen, however, the strain concentrated at the DS Cu near the interface for the notched specimen. This strain concentration arose from the mechanical heterogeneity between stainless steel and DS Cu in the bonded zone and attributed to the degradation of the absorbed energy of the joints.
-AlO and 
cells in the presence of desferrioxamine B; Implication of siderophores for the Ce anomalyYoshida, Takahiro; Ozaki, Takuo; Onuki, Toshihiko; Francis, A. J.*
Chemical Geology, 212(3-4), p.239 - 246, 2004/12
Times Cited Count：49 Percentile：64.22(Geochemistry & Geophysics)no abstracts in English
Yamada, Hirokazu*; Kawamura, Hiroshi; Tsuchiya, Kunihiko; Kalinin, G.*; Nagao, Yoshiharu; Sato, Satoshi; Mori, Kensuke*
Journal of Nuclear Materials, 335(1), p.33 - 38, 2004/10
Times Cited Count：8 Percentile：47.68(Materials Science, Multidisciplinary)no abstracts in English
Kinsho, Michikazu; Saito, Yoshio*; Kabeya, Zenzaburo*; Tajiri, Keisuke*; Nakamura, Tomaru*; Abe, Kazuhiko*; Nagayama, Taketoshi*; Nishizawa, Daiji*; Ogiwara, Norio
Vacuum, 73(2), p.187 - 193, 2004/03
Times Cited Count：17 Percentile：54.19(Materials Science, Multidisciplinary)Alimina ceramics vacuum duct has been developing at JAERI for the 3GeV-RCS of the J-PARC project. There are two type of the alumina ceramics vacuum ducts, one is a 1.5m-long duct with a circular cross section for use in the quadrupole magnet, the other is a 3.5m-long being bending 15 degree with an elliptical cross section for use in the dipole magnet.These ducts could be manufactured by brazed jointing several duct segments of 0.5-0.8 m long. Since some electrically conductive boundary is necessary to form on the ceramics duct in order to reduce the duct impedance, the alumina ceramics ducts have copper stripes on the outside surface of the ducts. This is called for rf shielding system. The copper stripes as rf shielding is produced by an electroforming method. In order to reduce emitting secondary electrons when primary protons or electrons impinge onto the surface, TiN film is coated inside surface of the alumina ceramics duct.
Kinsho, Michikazu; Saito, Yoshio*; Nishizawa, Daiji*; Michizono, Shinichiro*
Journal of Nuclear Materials, 318, p.307 - 312, 2003/05
Times Cited Count：11 Percentile：55.36(Materials Science, Multidisciplinary)In order to choose an alumina ceramic material for use as a vacuum beam duct in a rapid cycling synchrotron, several kinds of alumina ceramics, having different microstructures, were examined under radiation fields of 2.5 MeV electrons. Since a long ceramic duct can only be manufactured by glazing duct segments, the mechanical strength and deterioration not only a ceramics but also in the glazing joint were measured after irradiation. These ceramic have a sufficiently high flexural strength which is more than 300 MPa before electron beam irradiation, and we could get the experimental results that there was no deterioration on the flexural strength of the ceramic after 1000 MGy electron beam irradiation. No noticeable changes could be seen in the measured tensile strength of Ti-ceramic brazed samples after 1000 MGy electron beam irradiation.
