Study on the behavior of radiolytically produced hydrogen in a high-level liquid waste tank of a reprocessing plant; Comparison between actual and simulated solutions

Kinuhata, Hiroshi*; Yamamoto, Masahiko; Taguchi, Shigeo; Surugaya, Naoki; Sato, Soichi; Kodama, Takashi*; Tamauchi, Yoshikazu*; Shibata, Yuki*; Anzai, Kiyoshi*; Matsuoka, Shingo*

Nuclear Technology, 192(2), p.155 - 159, 2015/11

https://doi.org/10.13182/NT15-15

Experiments using a small-scale apparatus with 30 ml actual high-level liquid waste from the Tokai Reprocessing Plant were carried out to show that the hydrogen concentration in the gas phase reaches a steady-state value of much less than 4% (lower explosive limit) in the absence of sweeping-air. The H concentration reached a steady-state value as was expected and it was compared with a value predicted from an equation with parameters which had been obtained using the simulated solution. Satisfactory agreement showed that the Pd-ion catalytic H consumption reaction previously found in the simulated solution proceeded equally well in the actual solution.

Design of a 500kV electron gun for ERL light source at KEK

Yamamoto, Masahiro*; Honda, Yosuke*; Miyajima, Tsukasa*; Uchiyama, Takashi*; Kobayashi, Masanori*; Muto, Toshiya*; Matsuba, Shunya*; Sakanaka, Shogo*; Sato, Kotaro*; Saito, Yoshio*; et al.

Proceedings of 6th Annual Meeting of Particle Accelerator Society of Japan (CD-ROM), p.860 - 862, 2009/08

A newly 500 kV electron gun (2nd - 500 kV gun) for an ERL light source is designed at KEK. A new concept and state of-the-art technologies of vacuum system, ceramic insulators, high voltage power supply, photocathode and preparation system will be employed. The details are described in this report.

Highly polarized electrons from GaAs-GaAsP and InGaAs-AlGaAs strained-layer superlattice photocathodes

Nishitani, Tomohiro; Nakanishi, Tsutomu*; Yamamoto, Masahiro*; Okumi, Shoji*; Furuta, Fumio*; Miyamoto, Masaharu*; Kuwahara, Makoto*; Yamamoto, Naoto*; Naniwa, Kenichi*; Watanabe, Osamu*; et al.

Journal of Applied Physics, 97(9), p.094907_1 - 094907_6, 2005/05

https://doi.org/10.1063/1.1886888

no abstracts in English

Development and operational experiences of the JT-60U tokamak and power supplies

Hosogane, Nobuyuki; Ninomiya, Hiromasa; Matsukawa, Makoto; Ando, Toshiro; Neyatani, Yuzuru; Horiike, Hiroshi*; Sakurai, Shinji; Masaki, Kei; Yamamoto, Masahiro; Kodama, Kozo; et al.

Fusion Science and Technology (JT-60 Special Issue), 42(2-3), p.368 - 385, 2002/09

https://doi.org/10.13182/FST02-A234

This paper reviews developments of the JT-60U tokamak and coil power supplies and their operational experiences obtained to date. The JT-60U is a large tokamak upgraded from the original JT-60 to obtain high plasma current, large plasma volume and highly elongated divertor configurations. In the modification, all components inside the bore of toroidal magnetic field coils, a vacuum vessel, poloidal magnetic field coils (PF-coils), divertor etc., were renewed. Furthermore, boron carbide converted CFC tiles were used as divertor tiles to reduce erosion of carbon-base tiles. Later, a semi-closed divertor with pumps was installed in the replacement of the open divertor. Various technologies and ideas introduced to develop these components their operational experiences provide important data for designing future tokamaks. Also, major troubles that had influence on the JT-60U operations are described. As a maintenance issue for tokamaks using deuterium fueling gas, a method for reducing radiation exposure of in-vessel workers are introduced.

Development of a large volume negative-ion source for ITER neutral beam injector

Watanabe, Kazuhiro; Amemiya, Toru*; Hanada, Masaya; Iga, Takashi*; Imai, Tsuyoshi; Inoue, Takashi; Kashiwagi, Mieko; Kuriyama, Masaaki; Morishita, Takatoshi; Okumura, Yoshikazu; et al.

Review of Scientific Instruments, 73(2), p.1090 - 1092, 2002/02

https://doi.org/10.1063/1.1431422

no abstracts in English

Construction of negative-ion based NBI for JT-60U

Kawai, Mikito; Akino, Noboru; Ebisawa, Noboru; Honda, Atsushi; Ito, Takao; Kazawa, Minoru; Kuriyama, Masaaki; Mogaki, Kazuhiko; Oga, Tokumichi; Ohara, Hiroshi; et al.

JAERI-Tech 2001-073, 98 Pages, 2001/11

JAERI-Tech-2001-073.pdf:4.65MB

The world's first negative-ion based neutral beam injector(N-NBI) system has been developed for studies of non-inductive current drive and plasma core heating with high energy neutral beam injection in higher density plasma. Construction of the N-NBI system for JT-60U was completed in March 1996. The system is composed of a beamline with two ion souces, a set of ion source power supllies, control system and auxiliary sub-system such as cooling water, refrigeration and vaccum system. In July 2001, deuterium neutral beam injection of 400keV and 5.8MW into JT-60U plasma was achieved. In order to increase both beam power and energy we have to go on more improvement of the N-NBI.

Evaluation on strength of reinforced concrete slabs in Bituminization Demonstraion Facility

Yamada, Toshiro*; Morikawa, Hiroshi*; Ishida, Masatoshi*; Seto, Yutaka*; Yamamoto, Yoshifumi*; Sawamoto, Yoshikazu*

JNC TJ8410 98-002, 124 Pages, 1998/11

JNC-TJ8410-98-002.pdf:3.82MB

On the 11st of March 1997, a fire and explosion occurred in a Bituminization Demonstraion Facility. It subsequently became necessary to estimate the explosive force of this event. To this end, this report evaluates the static yield and ultimate strength of the main structural walls and floors of this facility. A simple method and a Finite Element Method (FEM) were considered to evaluate the yield and ultimate strength of reinforced concrete (RC) slabs. Using the simple method, the yield strength can be estimated effectively by solution of fundamental differential equations. The ultimate strength of RC slabs is tried to estimate using a modified yield line theory which is taken an arch effect created within RC slabs into account. However, this method is difficult to apply to slabs with complicated boundary conditions. In this case, FEM is necessary. The validity of the simple method is verified by analyzing some slabs using both methods and comparing the results. Previous experimental results and some RC slabs in the Asphalt Bituminization Facility were evaluated on the basis of yield and ultimate strength using both methods, and the validity of both methods were verified. Especially, in simulating previous experiments, the error in the estimated values of the ultimate strength using simple method to experimental values were within 30%. The estimated values of the ultimate strength using the FEM were 15% larger than the experimental values. As a result, the simple method taking arch effect into account was verified to some extent.

The Design study of the JT-60SU device, No.1; Objectives and outline of JT-60SU program

Kikuchi, Mitsuru; ; ; Miya, Naoyuki; Ushigusa, Kenkichi; Nagashima, Keisuke; Aoyagi, Tetsuo; ; Neyatani, Yuzuru; Naito, Osamu; et al.

JAERI-Research 97-026, 70 Pages, 1997/03

JAERI-Research-97-026.pdf:3.23MB

no abstracts in English

A Conceptual design of a negative-ion-grounded advanced tokamak reactor; NAVIGATOR(FER)

Yamamoto, Shin; Ohara, Yoshihiro; Tani, Keiji; Nishio, Satoshi; Okumura, Yoshikazu; Araki, Masanori; Azumi, Masafumi; R.S.Devoto*; Fujisawa, Noboru; Hitoki, Shigehisa*; et al.

JAERI-M 88-086, 183 Pages, 1988/05

JAERI-M-88-086.pdf:4.57MB

no abstracts in English

Proliferation resistance assessment of next generation reprocessing by INPRO-based JAEA methodology, 1; Comparison study on proliferation resistance of principal reprocessing technology from institutional barrier and technical barrier

Kuno, Yusuke; Koyama, Tomozo; Seya, Michio; Katsumura, Soichiro; Koma, Yoshikazu; Yamamoto, Tokuhiro

no journal, , 

A study on proliferation resistance assessment of next generation reprocessing by INPRO-based JAEA methodology was made, including Comparison Study on Proliferation Resistance of Principal Reprocessing Technology from Institutional Barrier and Technical Barrier.