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JAEA Reports

On performance experience and measurements with Ningyo Waste Assay System (NWAS), 3

Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Fujiki, Naoki*; Kado, Kazumi

JAEA-Technology 2013-050, 39 Pages, 2014/03

JAEA-Technology-2013-050.pdf:3.56MB

A uranium mass assay system NWAS, for 200-litter wastes drums applied by NDA method was developed and accumulated the data of the actual uranium bearing wastes drums. The system consists of the 16 pieces of Helium-3 proportional counters for neutron detection generated from U-234($$alpha$$,n) reaction or U-238 spontaneous fissions with polyethylene moderation and a Germanium solid state detector for $$gamma$$ ray detection as to determine uranium enrichment. The satisfactory works had been continued and the uranium determination data of 850 drums had been accumulated approximately. On the other hand several considerable problems on the system or methodology had been revealed technically or analytically through the measurements experiences. Furthermore as the next improvement plans, the active neutrons assay for uranium bearing wastes drums are now progressing. The results of complications will lead us to the progressive next steps.

Journal Articles

NWAS: Developments for passive uranium assay system, 2

Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Kado, Kazumi

Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-34-Kai Nenji Taikai Rombunshu (Internet), 10 Pages, 2013/10

A uranium mass assay system for 200-litter wastes drums applied by NDA method was developed and accumulated the data of the actual uranium bearing wastes drums. The system consists of the 16 pieces of Helium-3 proportional counters for neutron detection generated from $$^{234}$$U($$alpha$$,n) reaction or $$^{238}$$U spontaneous fissions with polyethylene moderation and a Germanium solid state detector for $$gamma$$ ray detection as to determine uranium enrichment. In previous report, some measurement experiences had been introduced briefly. After that satisfactory works had been continued and the uranium determination data of 850 drums had been accumulated approximately. On the other hand considerable problems on the system had been revealed technically or analytically. Such experiences are to be described precisely, in addition newly gained knowledge will be marshaled. Furthermore the next improvement plans are now prepared that will be capable of active neutrons assay for uranium bearing wastes drums.

Journal Articles

Trial plan for advanced NDA system of uranium wastes; Introduction of active neutron method applied to NDA system

Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Kado, Kazumi; Haruyama, Mitsuo; Takase, Misao; Ozu, Akira; Kureta, Masatoshi

Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-33-Kai Nenji Taikai Rombunshu (Internet), 8 Pages, 2012/10

We developed uranium mass assay systems for 200-litter wastes drums applied passive neutron measurements by NDA method and applied for the actual wastes drums stored in URCP. The neutron measurement methodology of $$^{234}$$U($$alpha$$,n) reaction using $$^{3}$$He proportional counters delivered superior performance, however also included some problems that the neutron penetration rates are depend upon matrices or density of wastes drums, so it was difficult to determine uranium mass against "unknown objects". For the purpose of solving problems active neutron measurements appears promising, we are now challenging to improve our equipments, which are composed of neutron generator, polyethylene moderators and $$^{3}$$He proportional counters. The uranium mass are determined by counting secondary neutrons generated from nuclear fissions. Our preliminary simulations suggest good performances with higher sensitivities and accuracies. It is extremely expected to contribute in the fields of safeguards works.

Journal Articles

Measurement system modification for advanced NDA system of uranium wastes; Performance evaluation of active neutron method applied to NDA system

Haruyama, Mitsuo; Takase, Misao; Ozu, Akira; Kureta, Masatoshi; Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Kado, Kazumi

Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-33-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2012/10

no abstracts in English

JAEA Reports

On performance experience and measurements with Ningyo Waste Assay System (NWAS), 2

Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Kado, Kazumi

JAEA-Technology 2012-023, 36 Pages, 2012/08

JAEA-Technology-2012-023.pdf:1.54MB

We developed uranium mass assay systems for 200-litter wastes drums applied neutron and $$gamma$$ measurements by NDA method. In this report we will describe measurement experiences followed by the previous report. The systems are composed of the 16 pieces of helium-3 ($$^{3}$$He) proportional counters for neutron detection. The neutron measurement methodology is consist of $$^{234}$$U ($$alpha$$,n)F reaction and spontaneous fission of $$^{238}$$U. The extensive test trials using the known amount of uranium with different enrichment and some kinds of matrices in drums were performed. By using this NWAS we tried to determine uranium mass in the actual uranium wastes drums stored in the URCP at Ningyo-toge. The actual uranium wastes drums are of great variety, in the point of matrix, bulk density, packing condition and total uranium mass. Therefore we have tried some challenging methods which eliminate problems, and established the applicability to almost all kinds of wastes drums.

Journal Articles

Source development and novel applications of laser-driven plasma X-ray lasers in JAEA

Kawachi, Tetsuya; Hasegawa, Noboru; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Oba, Toshiyuki; Kaihori, Takeshi; Kishimoto, Maki; Ochi, Yoshihiro; Tanaka, Momoko; et al.

X-Ray Lasers 2010; Springer Proceedings in Physics, Vol.136, p.15 - 24, 2011/12

This paper reviews recent improvement in the source development of laser-driven X-ray lasers and the applications in the research fields of material science, laser processing, X-ray imaging, and radiation damage in biological cells. In the application for material science, we have firstly observed temporal correlation between the domain structures of ferro-electric substance under the Curie temperature. In the laser processing, new X-ray laser interferometer reveals us the nano-scale surface distortion of substance pumped by a femto-second optical pulse. In the X-ray diffraction image, we have taken several static images of micro-structure of samples: now we are trying to extend the objective to nano-scale dynamics using pump and probe method. In the radiation damage of biological cells, we observed double strand break in DNA using X-ray laser exposure; this results are compared with the case using incoherent several KeV X-ray exposure.

Journal Articles

Decontamination performance evaluation of IF$$_{7}$$ treatment technology and proof of IF$$_{7}$$ production method

Ema, Akira; Kado, Kazumi; Suzuki, Kazuhiko*

Nihon Genshiryoku Gakkai Wabun Rombunshi, 10(3), p.194 - 204, 2011/09

This paper shows the investigation result of the reasonable IF$$_{7}$$ treatment condition and the full-scale examination result by using this IF$$_{7}$$ treatment condition. As a result, it could confirm 99% of the intermediate uranium fluoride in the cascade was removed for 60 days. Further, this paper shows the investigation result of the reasonable IF$$_{7}$$ production condition and the full-scale examination result. As a result, it could be proved 3,355 kg-IF$$_{7}$$ gas was produced.

Journal Articles

Proposal of method for quantifying uranium weight in the interior of gas centrifuge, and performance evaluation of IF$$_{7}$$ treatment reaction product separation and refinement

Ema, Akira; Kado, Kazumi; Suzuki, Kazuhiko*

Nihon Genshiryoku Gakkai Wabun Rombunshi, 10(3), p.205 - 215, 2011/09

This paper shows we constructed theoretically the methodology using the $$gamma$$-ray measured outside the gas centrifuge and MCNP code. Further, this paper shows the investigation result of the reasonable separation condition and the full-scale examination result. As a result, it could be proved IF$$_{5}$$ weight of 86% can separate and refine from UF$$_{6}$$ and IF$$_{5}$$ mixture gas.

JAEA Reports

On performance experience and measurements with Ningyo Waste Assay System (NWAS)

Zaima, Naoki; Nakashima, Shinichi; Kaneda, Koji; Kado, Kazumi

JAEA-Technology 2010-046, 31 Pages, 2011/02

JAEA-Technology-2010-046.pdf:2.84MB
JAEA-Technology-2010-046(errata).pdf:0.05MB

The uranium mass assay systems for 200-litter wastes drums applied neutron and $$gamma$$ measurements by NDA method had been developed. The measurement systems and trial data are described in this preliminary report. The systems are composed of the 16 pieces of helium-3 proportional counters for neutron detection and a large sized NaI(Tl) scintillation detector for $$gamma$$ ray detection. The extensive testing trials using the calibrated uranium sources with different enrichment and some kinds of matrices in drums were performed. Through the one year testing the useful experiences of this system concerning neutron and $$gamma$$ ray measurements for uranium mass were obtained. Almost all instruments and software were so good performance as is designed. As the next step we are scheduled to try measurements for actual wastes that are stored in the Uranium Refining and Conversion Plant at Ningyo-toge, and put practical uses near future. Our research was accomplished with the support of LANL.

Journal Articles

Uranium refining and conversion plant decommissioning project

Zaima, Naoki; Morimoto, Yasuyuki; Sugitsue, Noritake; Kado, Kazumi

Proceedings of 13th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM 2010) (CD-ROM), p.311 - 320, 2010/10

Journal Articles

C-axis critical current of a PrFeAsO$$_{0.7}$$ single crystal

Kashiwaya, Hiromi*; Shirai, Kazumi*; Matsumoto, Tetsuro*; Shibata, Hajime*; Kambara, Hiroshi*; Ishikado, Motoyuki; Eisaki, Hiroshi*; Iyo, Akira*; Shamoto, Shinichi; Kurosawa, Itaru*; et al.

Applied Physics Letters, 96(20), p.202504_1 - 202504_3, 2010/05

 Times Cited Count:27 Percentile:73.57(Physics, Applied)

The ${it c}$-axis transport properties of a high-pressure synthesized PrFeAsO$$_{0.7}$$ single crystal are studied using s-shaped junctions. Resistivity anisotropy of about 120 detected at 50 K shows the presence of strong anisotropy in the electronic states. The obtained critical current density for the ${it c}$-axis of 2.9 $$times$$ 10$$^{5}$$ A/cm$$^{2}$$ is two orders of magnitude larger than that in Bi$$_{2}$$Sr$$_{1.6}$$La$$_{0.4}$$CuO$$_{6+delta}$$. The appearance of a hysteresis in the current-voltage curve below ${it T}$ $$_{c}$$ is the manifestation of the intrinsic Josephson effect similar to that in cuprate superconductors. The suppression of the critical current-normal resistance (${it I}$ $$_{c}$$ ${it R}$ $$_{n}$$) product is explained by an inspecular transport in ${it s}$ $$_{pm}$$ -wave pair potential.

Journal Articles

Picosecond snapshot of the speckles from ferroelectric BaTiO$$_{3}$$ by means of X-ray lasers

Tai, R.; Namikawa, Kazumichi*; Kishimoto, Maki; Tanaka, Momoko; Sukegawa, Kota*; Hasegawa, Noboru; Kawachi, Tetsuya; Kado, Masataka; Lu, P.; Nagashima, Keisuke; et al.

Physical Review Letters, 89(25), p.257602_1 - 267602_4, 2002/12

 Times Cited Count:37 Percentile:81(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Progress in X-ray laser development at JAERI

Kato, Yoshiaki; Daido, Hiroyuki; Nagashima, Keisuke; Kawachi, Tetsuya; Hasegawa, Noboru; Tanaka, Momoko; Tang, H.; Tai, R.; Lu, P.; Kishimoto, Maki; et al.

AIP Conference Proceedings 641, p.31 - 39, 2002/00

no abstracts in English

Oral presentation

Recent progress in X-ray laser research in JAEA

Kawachi, Tetsuya; Kishimoto, Maki; Kado, Masataka; Tanaka, Momoko; Hasegawa, Noboru; Ochi, Yoshihiro; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Kunieda, Yuichi; et al.

no journal, , 

Recent progress in X-ray laser research in Japan Atomic Energy Agency is reviewed. Using the nickel-like silver soft X-ray laser at the wavelength of 13.9 nm, the application experiments have been conducted in the research fields such as material science, high-density plasma diagnostics, XRL ablation, XRL imaging using single-shot holography and atomic physics. The repetition rate of the XRL beam has been improved from each 10-20 minutes to 0.1 Hz by using new driver laser system with Nd: glass zigzag slab amplifier, and we are now constructing new beam line for the pump-probe measurement of the surface phase-transition by the method of X-ray laser interferometer. In the research activity on the extension of the wavelength region of the X-ray lasers, firstly, the demonstration of novel coherent X-ray generation by "flying mirror" technique is reported. The second is theoretical investigation of the resonance photo-pumping scheme toward water-window region.

Oral presentation

Recent progress on plasma X-ray laser and its application at JAEA

Kado, Masataka; Kawachi, Tetsuya; Ochi, Yoshihiro; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Sasaki, Akira; Hasegawa, Noboru; Kishimoto, Maki; Tanaka, Momoko; et al.

no journal, , 

Full coherent X-ray laser operating at 0.1 Hz are realized with originally developed high power laser system and double-target amplification scheme at JAEA. Utilizing the high spatial coherent several applications have been done recently such as study of temporal correlation of the domain fluctuation of BaTiO$$_{3}$$ with X-ray speckle measurement and X-ray interferometric measurement of nano-scale dynamics of solid surface with X-ray interferometer. Irradiating the X-ray laser onto biological cells DNA radiation damages showed different features comparing ordinary X-ray sources. Recent progress of X-ray laser development at JAEA and its applications will be presented.

Oral presentation

On performance experience and measurements with Ningyo Waste Assay System (NWAS)

Zaima, Naoki; Nakashima, Shinichi; Kaneda, Koji; Kado, Kazumi

no journal, , 

We developed uranium mass assay systems for 200-litter wastes drums applied neutron and $$gamma$$ measurements by NDA method. In this intermediate report we will describe measurement systems and trial data. The systems are composed of the 16 pieces of helium-3 proportional counters for neutron detection and a large sized NaI(Tl) scintillation detector for $$gamma$$-ray detection. The extensive testing trials using the calibrated uranium sources with different enrichment and some kinds of matrices in drums were performed. Through the one year testing the useful experiences of this system concerning neutron and $$gamma$$-ray measurements for uranium mass were obtained. Almost all instruments and software were so good performance as is designed. As the next step we are going to schedule to try measurements for actual wastes that are stored in the Uranium Refining and Conversion Plant at Ningyo-toge, and put practical uses near future. Our research was accomplished with the support of Los Alamos National Laboratory.

Oral presentation

The Experimental study for decontamination performance evaluation of IF$$_{7}$$ treatment technology

Ema, Akira; Kado, Kazumi; Suzuki, Kazuhiko*

no journal, , 

When uranium enrichment plant decommissioning is carried out, a reasonable gas centrifuge decontamination technology is required. The present study proposes a dry treatment technology using Iodine Heptafluoride (IF$$_{7}$$) gas. As a result, we observe experimental decontamination performance.

Oral presentation

Proposal for the decontamination method of the radioactive substances by the chemical reaction

Ema, Akira; Kado, Kazumi; Suzuki, Kazuhiko*

no journal, , 

In the nuclear industry, when the nuclear facilities is dismantled, the decontamination work of the radioactive substances is carried out. The selection of the decontamination method is a big problem because the enlargement of decontamination plant and increases of disposal cost is caused. In this study, we propose the new decontamination method of the uranium compounds by IF$$_{7}$$ gas.

Oral presentation

Experiences of NWAS, 2

Zaima, Naoki; Nakashima, Shinichi; Nakatsuka, Yoshiaki; Kado, Kazumi

no journal, , 

We developed uranium mass assay systems for 200-litter wastes drums applied neutron and $$gamma$$ measurements by NDA method. In this intermediate report we will describe measurement systems and trial data. The systems are composed of the 16 pieces of helium-3 proportional counters for neutron detection and a Germanium solid state detector for $$gamma$$ ray detection. The extensive testing trials using the calibrated uranium sources with different enrichment and some kinds of matrices in drums were performed. Through the one year testing the useful experiences of this system concerning neutron and $$gamma$$ ray measurements for uranium mass were obtained. Almost all instruments and software were so good performance as is designed. As the next step we are now trying the measurements for actual wastes that are stored in the Uranium Refining and Conversion Plant at Ningyo-toge, and put practical uses near future. Our research was accomplished with the support of LANL.

Oral presentation

The Study of the decontamination technology for the radioactive waste reduction

Ema, Akira; Kado, Kazumi; Suzuki, Kazuhiko*

no journal, , 

We carried out the full-scale exam of the IF$$_{7}$$ production for the study of the decontamination technology using IF$$_{7}$$ gas. As a result, it could be proved 3,355kg-IF$$_{7}$$ gas was produced.

25 (Records 1-20 displayed on this page)