Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Watanabe, Kazuki; Kimura, Norimichi*; Okada, Jumpei; Furuuchi, Yuta; Kuwana, Hideharu*; Otani, Takehisa; Yokota, Satoru; Nakamura, Yoshinobu
JAEA-Technology 2023-010, 29 Pages, 2023/06
The Krypton Recovery Development Facility reached an intended technical target (krypton purity of over 90% and recovery rate of over 90%) by separation and rectification of krypton gas from receiving off-gas produced by the shearing and the dissolution process in the spent fuel reprocessing at the Tokai Reprocessing Plant (TRP) between 1988 and 2001. In addition, the feasibility of the technology was confirmed through immobilization test with ion-implantation in a small test vessel from 2000 to 2002, using a part of recovered krypton gas. As there were no intentions to use the remaining radioactive krypton gas in the krypton storage cylinders, we planned to release this gas by controlling the release amount from the main stack, and conducted it from February 14 to April 26, 2022. In this work, all the radioactive krypton gas in the cylinders (about 7.110 GBq) was released at the rate of 50 GBq/min or less lower than the maximum release rate from the main stuck stipulated in safety regulations (3.710 GBq/min). Then, the equipment used in the controlled release of radioactive krypton gas and the main process (all systems, including branch pipes connected to the main process) were cleaned with nitrogen gas. Although there were delays due to weather, we were able to complete the controlled release of radioactive krypton gas by the end of April 2022, as originally targeted without any problems such as equipment failure.
Hansen, S. B.*; Fournier, K. B.*; Faenov, A. Y.*; Magunov, A. I.*; Pikuz, T. A.*; Skobelev, I. Y.*; Fukuda, Yuji; Akahane, Yutaka; Aoyama, Makoto; Inoue, Norihiro*; et al.
Physical Review E, 71(1), p.016408_1 - 016408_9, 2005/01
Times Cited Count:16 Percentile:57.59(Physics, Fluids & Plasmas)X-ray line emission from ' transitions in Ne-like Kr and nearby ions has been observed from 1 m Kr clusters irradiated by fs-scale laser pulses at the JAERI facility in Kyoto, Japan. The dependence of X-ray spectral features and intensity on the incident laser intensity is rather weak, indicating that the 1-2 ps cluster lifetimes limit the number of ions beyond Ne-like Kr that can be produced by collisional ionization. A collisional-radiative model based on the relativistic multiconfigured FAC code has been constructed and used to determine that the cluster plasma has electron densities near 10 cm, temperature of a few hundred eV and hot electron fraction of a few percent.
Smirnov, M. B.*; Skobelev, I. Y.*; Magunov, A. I.*; Faenov, A. Y.*; Pikuz, T. A.*; Fukuda, Yuji; Yamakawa, Koichi; Akahane, Yutaka; Aoyama, Makoto; Inoue, Norihiro*; et al.
Journal of Experimental and Theoretical Physics, 98(6), p.1123 - 1132, 2004/06
Interaction between high-power ultrashort laser pulse and giant clusters (microdroplets) consisting of 10 to 10 atoms is considered. The microdroplet size is comparable to the laser wavelength. A model of the evolution of a microdroplet plasma induced by a high-power laser pulse is developed, and the processes taking place after interaction with the pulse are analyzed. It is shown theoretically that the plasma is superheated: its temperature is approximately equal to the ionization potential of an ion having a typical charge. The microdroplet plasma parameters are independent of the pulse shape and duration. The theoretical conclusions are supported by experimental studies of X-ray spectra conducted at JAERI, where a 100-terawatt Ti-sapphire lasersystem was used to irradiate krypton and xenon microdroplets by laser pulses with pulse widths of 30 to 500 fs and intensities of 610 to 210 W/cm.
Ogawa, Hiroaki; Kiuchi, Kiyoshi; Saburi, Tei; Fukaya, Kiyoshi
JAERI-Research 2001-023, 21 Pages, 2001/03
no abstracts in English
Moribayashi, Kengo; Zhidkov, A. G.; Sasaki, Akira; Sudo, Keiko; Suzuki, Shingo*
Proceedings of 2nd International Conference on Inertial Fusion Sciences and Applications (IFSA 2001), p.1182 - 1185, 2001/00
no abstracts in English
Iguchi, Tetsuo; Watanabe, Kenichi*; *; Nose, Shoichi; Harano, Hideki;
JNC TY9400 2000-019, 34 Pages, 2000/05
None
Sagawa, Norihiko*
PNC TJ9613 97-002, 95 Pages, 1997/10
The diffusion coefficient of cesium iodide vapor in rare gases was determined by a modified Stefan's method. The rare gas in a diffusion column was saturated with vapor of the cesium iodide, crystals of which were heated to melt at the bottom of the column. By opening a valve united at a top of the column, the vapor diffusing through the column was transferred with the carrier rare gas to an ionization sensor. The concentration of cesium iodide in the carrier gas was continuously monitored with the sensor. The diffusion coefficient was determined by analyzing the transient response of the concentration. Increasing tendency with temperature is observed in the coefficients obtained in argon, kripton and xenon at temperatures between 631 and 691 C and no significant difference among the coefficients in argon, krypton and xenon.
Shirai, Toshizo; Sugar, J.*; Wiese, W. L.*
JAERI-Data/Code 97-030, 63 Pages, 1997/07
no abstracts in English
*
PNC TJ9602 96-004, 49 Pages, 1996/03
To check the accuracy of helium accumulation neutron fluence monitoring (HAFM) technique and the applicability of tag gas activation analysis to fast reactor failed fuel detection, these samples were irradiated at the standard neutron field of the fast neutron source reactor "YAYOI" (Nuclear Engineering Research Laboratory, University of Tokyo). The HAFM samples of 93% enriched B powder of 1 mg contained in a V capsule were set up in the reactor core center (Glory hole :Gy) and another samples including V encapsulated natural B powder of 10 mg, natural B chips and 96% enriched LiF thermoluminescence dosimeters were in the leakage neutron field from the reactor core (Fast column :FC). These neutron fields were monitored by the activation foils consisting of Al, Fe, Co, Ni, Cu, Ti, In, Au, U, Np etc., which were used to derive the neutron flux and spectrum. At the end of March in 1996, the irradiated neutron fluence in the energy more than 0.1Mev reached up to 1.110 n/cm at Gy and 5.410 n/cm at FC, respectively. Two kinds of tag gas samples, which are the mixed gases of isotipically adjusted Xe and Kr contained in stainless steel (SUS) capsules, were irradiated twice at Gy; one is up to 9kWh and the other 7kWh, and after the irradiation, -ray spectra were measured for each sample. Through comparison with the -ray spectrum from dummy capsule of no tag gas, the -ray peaks of Kr, Xe etc., which would be produced from tag gas activation, were able to be clearly identified.
Komaki, Yoshihide; ; ; ; Sakurai, Tsutomu; ; Kobayashi, Yoshii; Adachi, Takeo
Nihon Genshiryoku Gakkai-Shi, 33(5), p.489 - 497, 1991/05
Times Cited Count:0 Percentile:0.01(Nuclear Science & Technology)no abstracts in English