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Nakamura, Shoji; Hatsukawa, Yuichi*; Kimura, Atsushi; Toh, Yosuke; Harada, Hideo
Journal of Nuclear Science and Technology, 58(12), p.1318 - 1329, 2021/12
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)The present study performed fast-neutron capture cross-section measurement of Tc by an activation method using a fast-neutron source reactor "YAYOI" of the University of Tokyo. Technetium-99 samples were irradiated with reactor neutrons using a pneumatic system. Reaction rates of Tc were obtained by measuring decay gamma rays emitted from Tc. The neutron flux at an irradiation position was monitored with gold foils. The fast-neutron capture cross section of Tc at neutron energy of 85 keV was derived as 0.4320.023 barn by using the reaction rates of Tc, evaluated cross-section data and the fast-neutron flux spectrum of the YAYOI reactor. The present study agreed with the evaluated nuclear data library JENDL-4.0.
Project 6 Meeting Members for Tsukuba International Strategic Zone
JAEA-Review 2021-016, 102 Pages, 2021/11
In December 2011, the Prime Minister designated Tsukuba and some areas in Ibaraki Prefecture as "Comprehensive Special Zones". In the Tsukuba International Strategic Zone, nine advanced research and development (R&D) projects are underway with the goal of promoting industrialization of life innovation and green innovation utilizing the science and technology in Tsukuba. In these projects, the domestic production of medical radioisotope (Technetium-99m, Tc) was certified as a new project in October 2013, and R&D have been performed in collaboration with related organizations with Japan Atomic Energy Agency (JAEA) as the project leader. Japan is the third largest consumer of molybdenum-99 (Mo) after the United States and Europe, and all Mo are imported. Supply will be insufficient if overseas reactors are shut down due to trouble or if transportation (air and land transportations) is stopped due to volcanic eruptions and some accidents. Thus, early domestic production of Mo is strongly required. This project is a technology development aimed at domestic production of Mo, which is a raw material of Tc used as a diagnostic agent. This report summarizes the activities carried out in the first and second phase of the domestic production of medical radioisotope (Tc) (here referred to as the "Project 6") in Tsukuba International Strategic Zone (FY2014-2020).
Mineo, Hideaki; Asakura, Toshihide; Hotoku, Shinobu; Ban, Yasutoshi; Morita, Yasuji
Proceedings of GLOBAL2003 Atoms for Prosperity; Updating Eisenhower's Global Vision for Nuclear Energy (CD-ROM), p.1250 - 1255, 2003/11
An advanced aqueous reprocessing process has been proposed for the next generation fuel cycle. Key technologies applied to the process are: removal of I-129, separation of Np and FP(Tc) separation by selective reduction of Np(VI) and high acid scrubbing of Tc within a single cycle process, MA separation by extraction chromatography and Cs/Sr separation. U separation just after dissolution was supposed to be effective to reduce the required capacity of the following extraction step. Among them Np reduction rate in TBP solution was measured, which was found to be lower than that in aqueous solution. Using an improved flow sheet spent fuel test, based on the Np reduction test, was carried out and about 90% of Np was separated before U and Pu partitioning step.
Nakagawa, Tsuneo; Iwamoto, Osamu; Hasegawa, Akira
JAERI-Research 2002-035, 94 Pages, 2002/12
no abstracts in English
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JNC TJ9400 2000-009, 63 Pages, 2000/02
The present status of nuclear data for technetium (Tc)-99, which is a well-known fission product (FP), has been reviewed and investigated. And making use of the Kyoto university Lead Slowing-down Spectrometer (KULS), the cross section of the Tc (n, ) Tc reaction has been measured in the energy range from thermal to keV neutron energy with an Ar-gas proportinal counter. The neutron flux/spectrum has been monitored with a BF proportional counter, and the relative measurement has been normalized to the well-known standard capture cross section value for the Tc (n, ) Tc reaction at 0.0253 eV. Self-shielding corrections, especially near the resonance peaks, were made by the calculations with the MCNP code. Although the experimental data measured by Chou et al with a lead slowing-down spectrometer are higher in general, the energy dependency is similar to the present measurement. The evaluated data in ENDF/B-VI and JENDL-3.2 are higher near the resonances at 5.6 and 20 eV and above several 100 eV. A lead slowing-down spectrometer was installed coupled to a 46 MeV electron linac at the Research Reactor Institute, Kyoto university (KURRI). Characteristics of the Kyoto University Lead Slowing-down Spectrometer (KULS) were measured and (1)the relation between neutron slowing-down time t(s) and energy E(keV) (E=190/t in Bi hole and E=156/t in Pb hole) and (2)the energy resolution (40% in Bi and Pb holes) were experimentally investigated. (3)The neutron energy spectrum in the KULS was also measured by the neutron TOF method. The results obtained by the MCNP code were in general agreement with these experimental ones.
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JNC TJ9400 2000-008, 61 Pages, 2000/02
For studies on nuclear transmutation of long-lived fission products (LLFPs) in a fast reactor, detailed characteristics of reactor core such as transmutation performance have to be investigated, so accurate neutron cross section data of LLFPs become necessary. Therefore, the keV-neutron capture cross sections of Tc-99, which is one of important LLFPs, were measured in the present study to obtain the accurate data. The measurement was relative to the standard capture cross sections of Au-197. A neutron time-of-flight method was adopted with a ns-pulsed neutron source by a Pelletron accelerator and a large anti-Compton NaI(TI) gamma-ray detector. As a result, the capture cross sections of Tc-99 were obtained with the error of about 5 % in the incident neutlon energy region of 10 to 600 keV. The present data were compared with other experimental data and the evaluated values of JENDL-3.2, and it was found that the evaluations of JENDL-3.2 were 15-20 % smaller than the present measurements.