Operation of the electron accelerator and the Co -ray irradiation facilities

Uno, Sadanori; Hanaya, Hiroaki; Yamagata, Ryohei; Seito, Hajime; Nagao, Yuto; Yamasaki, Shota; Agematsu, Takashi; Kawashima, Ikuo*; Yagi, Norihiko*; Takagi, Masahide*; et al.

JAEA-Review 2015-022, JAEA Takasaki Annual Report 2014, P. 172, 2016/02

https://doi.org/10.11484/jaea-review-2015-022

This paper reports on the operation status of the -ray irradiation facilities and the electron accelerator in fiscal 2014 at the Takasaki Advanced Radiation Research Institute of JAEA. The -ray irradiation facilities were operated smoothly, whereas the electron accelerator stopped for five months because of successive troubles of discharge due to deterioration of equipment over thirty-four years. The annual operation times of the -ray irradiation facilities of the first, second and food buildings were 19,907, 13,831 and 7,293 hours, respectively, and that of the electron accelerator was 746 hours. The -ray irradiation facilities were replenished with new five sources of 2.22 PBq, and twenty old sources were removed for disposal. The electron accelerator was repaired for each trouble, however, the complete recovery has not yet been achieved.

Hydrogen at zinc vacancy of ZnO; An EPR and ESEEM study

Son, N. T.*; Isoya, Junichi*; Ivanov, I. G.*; Oshima, Takeshi; Janzn, E.*

AIP Conference Proceedings 1583, p.341 - 344, 2014/02

Hardening of Fe-Cu model alloys induced by electron irradiation and neutron irradiation

Tobita, Toru; Aizawa, Kazuya; Suzuki, Masahide; Iwase, Akihiro*

Nihon Genshiryoku Gakkai Wabun Rombunshi, 3(4), p.331 - 339, 2004/12

https://doi.org/10.3327/taesj2002.3.331

Nevertheless, there is a possibility that -ray induces embrittlement more efficiently than fast neutron, the irradiation effect of -ray has not been fully clarified. Comparative experiments on irradiation hardening by 2.5MeV electron irradiation for the purpose of -ray irradiation and neutron irradiation were performed to the Fe-Cu model alloys. We obtained the dose dependence and the temperature dependence on irradiation induced hardening. The growth of Cu clusters with increase in irradiation dose was confirmed by the small angle neutron scattering measurements. Although the differences in hardening between electron and neutron irradiations were very small on a displacement-per-atom (dpa) basis, the electron irradiation hardening initiated slightly earlier than the neutron. The growth of Cu clusters with increase in irradiation dose was the principal cause of hardening. The present results suggested that, from an engineering point of view, both the -ray induced and neutron induced hardening can be well scaled by using dpa.

Hydrogen migration in electron irradiated Pd based dilute alloys around the 50 K anomaly

Yamakawa, Koji*; Chimi, Yasuhiro; Ishikawa, Norito; Iwase, Akihiro*

Journal of Alloys and Compounds, 370(1-2), p.211 - 216, 2004/05

https://doi.org/10.1016/j.jallcom.2003.09.037

The migration of hydrogen in Pd-1at.% Fe-H and Pd-1at.% Ag-H alloys is investigated by electrical resistivity measurement around 50 K. The disordered hydrogen atoms are introduced by electron irradiation with 0.5 MeV electrons below 15 K. The disordered atoms order by migration of hydrogen atoms during the heating-up of the specimens. The recovery curves of electrical resistivity have two sub-stages for electron irradiated specimens and one stage for fast cooled specimens. The migration energy of hydrogen is obtained from the kinetic analysis of the resistivity change due to the ordering, using the cross-cut method for the electron irradiated specimen and fast cooled specimen. The obtained value of the migration energy for the low temperature stage is smaller than that for the high temperature stage. The value for the high temperature stage is similar to the energy for the case of fast cooling. The difference between the hydrogen atoms disordered by irradiation and that by fast cooling is discussed for Pd based alloys.

Evaluation of corrosion behavior of ion irradiated stainless steel using atomic force microscope

Nemoto, Yoshiyuki; Miwa, Yukio; Tsuji, Hirokazu; Tsukada, Takashi

Dai-12-Kai MAGDA Konfarensu (Oita) Koen Rombunshu, p.191 - 196, 2003/00

Development and research about analytical method for the study of corrosion behavior of austenitic stainless steel after irradiation was conducted from the point of view for basic study of IASCC (Irradiation Assisted Stress Corrosion Cracking). Ion irradiations were conducted with several irradiation conditions these were irradiation temperature, radiation damage, the contents of helium (He) implantation. AFM (Atomic Force Microscope) was used to evaluate surface condition of irradiated specimens after corrosion procedure. Corrosion condition was developed to obtain good surface condition of irradiated specimens to evaluate corrosion behavior by AFM. It was succeeded and corrosion behavior at inside of grains and grain boundaries of irradiated specimens was obtained. EBSP (Electron Backscatter Diffraction Pattern) was used to evaluate relation of corrosion behavior with grain boundary character. Moreover, relations of corrosion behavior with irradiation condition were discussed.

Electro-electrodialysis of hydriodic acid using the cation exchange membrane cross-linked by accelerated electron radiation

Arifal; Hwang, G.; Onuki, Kaoru

Journal of Membrane Science, 210(1), p.39 - 44, 2002/12

https://doi.org/10.1016/S0376-7388(02)00372-1

no abstracts in English

Irradiation effects on MgB bulk samples and formation of columner defects on high-Tc supercoductor

Okayasu, Satoru; Sasase, Masato; Hojo, Kiichi; Chimi, Yasuhiro; Iwase, Akihiro; Ikeda, Hiroshi*; Yoshizaki, Ryozo*; Kambara, Tadashi*; Sato, H.*; Hamatani, Yutaro*; et al.

Physica C, 382(1), p.104 - 107, 2002/10

https://doi.org/10.1016/S0921-4534(02)01206-6

no abstracts in English

-scaling of lattice parameter change in high ion-velocity region ( 2.610 cm/s) in ion-irradiated EuBaCuO

Ishikawa, Norito; Iwase, Akihiro; Chimi, Yasuhiro; Michikami, Osamu*; Wakana, Hironori*; Hashimoto, Takeo*; Kambara, Tadashi*; Mller, C.*; Neumann, R.*

Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.278 - 282, 2002/06

https://doi.org/10.1016/S0168-583X(02)00774-7

Swift heavy ions with wide energy range of 80MeV-3.84GeV have been irradiated to EuBaCuO oxide superconductors, and the lattice parameter change due to elecronic excitation has been measured. In the high ion-velocity region, the change in lattice parameter per unit fluence varies as the 4th power of the electronic stopping power. However, in the low-velocity region, the deviation from the 4th power dependence is observed. The results are analyzed by using the primary ionization rate, and it is found that the results support that the Coulomb explosion triggers the atomic displacements.

Hardening of Fe-Cu alloys at elevated temperatures by electron and neutron irradiations

Tobita, Toru; Suzuki, Masahide; Iwase, Akihiro; Aizawa, Kazuya

Journal of Nuclear Materials, 299(3), p.267 - 270, 2001/12

https://doi.org/10.1016/S0022-3115(01)00694-8

no abstracts in English

Characterization and evaluation studies on some JAERI dosimetry systems

Kojima, Takuji; Sunaga, Hiromi; Tachibana, Hiroyuki; Takizawa, Haruki; Tanaka, Ryuichi

IAEA-TECDOC-156, p.91 - 98, 2000/06

no abstracts in English