Development and operation of an electrostatic time-of-flight detector for the Rare RI storage Ring

Nagae, Daisuke*; Abe, Yasushi*; Okada, Shunsuke*; Omika, Shuichiro*; Wakayama, Kiyoshi*; Hosoi, Shun*; Suzuki, Shinji*; Moriguchi, Tetsuro*; Amano, Masamichi*; Kamioka, Daiki*; et al.

Nuclear Instruments and Methods in Physics Research A, 986, p.164713_1 - 164713_7, 2021/01

https://doi.org/10.1016/j.nima.2020.164713

The Concept of dose system for radiological protection

Hirayama, Hideo*; Nakashima, Hiroshi; Sanami, Toshiya*; Yamaguchi, Yasuhiro; Sato, Osamu*; Takagi, Shunji*; Suzuki, Toshikazu*; Iwai, Satoshi*

Nihon Genshiryoku Gakkai-Shi ATOMO, 55(2), p.83 - 96, 2013/02

Since the accident at the Fukushima Daiichi Power Plant, units of radiation doses such as Sv have been frequently reported by newspapers. However, it is not exactly understood even by experts on nuclear engineering that there are two different concepts which are the protection quantity such as the effective dose related to a radiation health risk and the practical quantity such as ambient dose equivalents related to measurements. In this special issue, Radiological Protection Quantity, and Operational Quantity and Radiological Protection Quantity, explain the radiation protection dose system including the protection and practical quantities established by ICRP and ICRU. Relation between Dosimeters used at Fukushima etc. and Radiological Protection Quantity describes a method and its problems to measure radiations from Cs on surface and underground using survey meters and personal dosimeters, and convert the measured values to effective doses.

Proposal of a Nuclear Cycle Research and Development Plan in Tokai Works -The Roadmap from LWR Cycle to FBR Cycle-

Nakamura, Hirofumi; Abe, Tomiyuki; Kashimura, Takao; Nagai, Toshihisa; Maeda, Seiichiro; Yamaguchi, T.; Kuroki, Ryoichiro

JNC TN8440 2003-016, 39 Pages, 2003/07

JNC-TN8440-2003-016.pdf:0.79MB

The Generation-II Project Task Force Team has investigated a research and development plan on a future nuclear fuel cycle in Tokai works for about three months from December 19,2002. First we have discussed about the present condition of Japanese nuclear fuel cycle and have recognized it as the following. *The relation of the technology between the LWR-cycle and the FBR-cycle is not clear. *MOX Fuel Use in Light Water Reactors is important to establish technology of the FBR fuel cycle. *Radioactive waste disposal issue is urgent. Next we have proposed the three basic policies on R&D plan of nuclear fuel cycle in consideration of the F.S. on FBR-cycle. *Establishment and advancement of "the tough nuclear fuel cycle". *Early establishment of the FBR cycle technology to be able to supply energy stably for long-term. *Establishment of the radioactive waste treatment and disposal technology, and optimization of nuclear fuel cycle technology from the viewpoint of radioactive waste.And we have proposed the Japanese technical holder system to integrate all LWR and FBR cycle technology.

Behavior of carbon-14 in the Tokai reprocessing plant

; ; ; Omori, Eiichi

JNC TN8410 2001-021, 33 Pages, 2001/09

JNC-TN8410-2001-021.pdf:4.37MB

Carbon-14 released from the nuclear facilities is an important radionuclide for the safety assessment, because it tends to accumulate in environment through food chain and has as a significant impact to personal dose. Carbon-14 has been monitored routinely as one of the main gaseous radionuclides exhausted from the Tokai Reprocessing Plant (TRP) since OCtober of 1991. Furthermore, behavior of carbon-14 in TRP has been investigated through the reprocessing operation and the literature survey. This report describes the result of investigation about the behavior of carbon-14 in TRP as followings. (1)Only a very small amount of carbon-14 in the fuel was liberated into the shear off-gas and most of it was liberated into the dissolver of-gass. Part of the carbon-14 was trapped at the caustic scrubber installed in the of-gas treatment process, and untrapped carbon-14 was released into the environment from the main stack. Amount of carbon-14 released from the main stack was about 4.16.5GBq every ton of uranium reprocessed. (2)Carbon-14 trapped at the caustic scrubbers installed in the dissolver off-gas and in the vessel off-gas treatment process is transferred to the low active waste vessel. Amount of carbon-14 transferred to the low active waste vessel was about 5.4 9.6GBq every ton of uranium reprocessed. (3)The total amount of carbon-14 input to TRP was summed up to about 11.915.5 GBq every ton of uranium reprocessed considering the released amount from the main stack and the trapped amount in the off-gas treatment devices. The amount of nitrogen impurity in the initial fuel was calculated about 1522ppm of uranium metal based on the measured carbon-14. (4)The solution in the low active waste vesselis concentrated at the evaporator.Most of the carbon-14 in the solution was transferred into concentrated solution. (5)Tokai vitrification Demonstration Facility (TVF) started to operate in 1994. Since then, carbon-14 has been measured in the ...

Growth and structural properties of -FeSi layers on glass substrates

Satake, Toshiya*; Yamaguchi, Kenji; Yamamoto, Hiroyuki; Matsuyama, Takashi*; Tatsuoka, Hirokazu*

no journal, , 

-FeSi layers were grown on insulating substrates by reactive deposition epitaxy (RDE). As substrate, SIMOX (Separation by implanted oxygen) was used as well as silica substrates with pre-deposited thin poly-silicon layers. The structural properties of the -FeSi layers have been investigated using X-ray diffraction technique (XRD) and transmission electron microscopy (TEM).

Measurement of of 230 MeV/u incident charged particles production double differential cross section

Furuta, Toshimasa*; Uozumi, Yusuke*; Yamaguchi, Yuji; Iwamoto, Yosuke; Sanami, Toshiya*; Koba, Yusuke*

no journal, , 

no abstracts in English