Refine your search:     
Report No.
 - 
Search Results: Records 1-14 displayed on this page of 14
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Survey on effect of crystal texture of beryllium on total cross-section to improve neutronic evaluation in JMTR

Takemoto, Noriyuki; Imaizumi, Tomomi; Kimura, Nobuaki; Tsuchiya, Kunihiko; Hori, Junichi*; Sano, Tadafumi*; Nakajima, Ken*

Proceedings of International Conference on the Physics of Reactors; The Role of Reactor Physics toward a Sustainable Future (PHYSOR 2014) (CD-ROM), 11 Pages, 2014/09

Neutronic evaluations in JMTR have been performed for irradiation tests by Monte Carlo method with thermal neutron scattering law, S($$alpha$$, $$beta$$), data for beryllium metal, etc. The calculation accuracy of fast and thermal neutron fluxes are $$pm$$10% and $$pm$$30%, respectively. Analytical and experimental investigations to achieve higher calculation accuracy, especially for the thermal neutron flux up to the fast neutron flux level, have been therefore performed to offer higher value data technically to the JMTR users. In order to investigate an effect of fabrication method of beryllium material on the calculation accuracy, total cross-sections of beryllium specimens were measured using KURRI-LINAC, and it was found that the total cross-section was different from the theoretical one, and depended on the crystal texture, etc. The S($$alpha$$, $$beta$$) was adjusted based on the measured data, and the applicability to the neutronic evaluation in the JMTR was verified.

JAEA Reports

Conceptual design of multipurpose compact research reactor; Annual report FY2011

Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.

JAEA-Technology 2013-021, 43 Pages, 2013/07

JAEA-Technology-2013-021.pdf:5.12MB

The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.

JAEA Reports

Density of Bunsen reaction solution and viscosity of poly-hydriodic acid

Kubo, Shinji; Yoshino, Koji*; Takemoto, Jumpei*; Kasahara, Seiji; Imai, Yoshiyuki; Onuki, Kaoru

JAEA-Technology 2012-037, 20 Pages, 2013/01

JAEA-Technology-2012-037.pdf:17.29MB

Densities of Bunsen reaction solutions in the iodine-sulfur process were measured with an oscillating U-tube density meter. Two types of the solutions were prepared to simulate sulfuric acid solutions and hydriodic acid solutions of the Bunsen reaction step. The former solution ranged in concentration from 0 to 45 wt% of sulfuric acid containing HI and I$$_{2}$$ of 0-2 mole%; the latter solution contained 0-17 mole% I$$_{2}$$, 1-15 mole% HI and 0-2 mole% H$$_{2}$$SO$$_{4}$$. The temperature of the measured solution were 10-60 $$^{circ}$$C. It was found that, in both solutions, the effect of HI and I$$_{2}$$ concentration on the density could well be represented by using a kind of mole fraction of iodine atom. Based on the finding, a set of correlation equations between the densities and the compositions were derived. Additionally, viscosities of ploy-hydriodic acid were measured using an oscillating viscosity meter in temperature range of 5-40 $$^{circ}$$C, and in the composition range of 0-17 mole% I$$_{2}$$ and 1-15 mole% HI; a empirical equation to calculate viscosity from the composition and the temperature are obtained.

JAEA Reports

Design, fabrication and transportation of Si rotating device

Kimura, Nobuaki; Imaizumi, Tomomi; Takemoto, Noriyuki; Tanimoto, Masataka; Saito, Takashi; Hori, Naohiko; Tsuchiya, Kunihiko; Romanova, N. K.*; Gizatulin, S.*; Martyushov, A.*; et al.

JAEA-Technology 2012-012, 34 Pages, 2012/06

JAEA-Technology-2012-012.pdf:12.91MB

Si semiconductor production by Neutron Transmutation Doping (NTD) method using the Japan Materials Testing Reactor (JMTR) has been investigated in Neutron Irradiation and Testing Reactor Center, Japan Atomic Energy Agency (JAEA) in order to expand industry use. As a part of investigations, irradiation test of silicon ingot for development of NTD-Si with high quality was planned using WWR-K in Institute of Nuclear Physics (INP), National Nuclear Center of Republic of Kazakhstan (NNC-RK) based on one of specific topics of cooperation (STC), Irradiation Technology for NTD-Si (STC No.II-4), on the implementing arrangement between NNC-RK and the JAEA for "Nuclear Technology on Testing/Research Reactors" in cooperation in research and development in nuclear energy and technology. As for the irradiation test, Si rotating device was fabricated in JAEA, and the fabricated device was transported with irradiation specimens from JAEA to INP-NNC-RK. This report described the design, the fabrication, the performance test of the Si rotating device and transportation procedures.

JAEA Reports

Newly organized training course using JMTR and related facilities as advanced research infrastructures

Imaizumi, Tomomi; Takemoto, Noriyuki; Izumo, Hironobu; Ide, Hiroshi; Matsui, Yoshinori; Sozawa, Shizuo; Hori, Naohiko

JAEA-Review 2012-012, 25 Pages, 2012/03

JAEA-Review-2012-012.pdf:4.21MB

A training course using JMTR and the related facilities was newly organized for domestic students and young engineers from FY 2010 from a viewpoint of nuclear Human Resource Development (HRD) in order to support global expansion of nuclear power industry. In FY2010, preparation for the training course was curried out and the 1st training course was held on February 14 to 25, 2011 with ten domestic students as a trainie. In this training course, mainly carried out was practical training of neutronic calculation for an irradiation test about the hydraulic rabbit irradiation facility which is one of the irradiation facilities in the JMTR. This report summarizes outline of training course using cutting-edge research infrastructure JMTR and the related facilities and result of the 1st training course.

Journal Articles

Real time simulator for material testing reactor

Takemoto, Noriyuki; Imaizumi, Tomomi; Izumo, Hironobu; Hori, Naohiko; Suzuki, Masahide; Ishitsuka, Tatsuo*; Tamura, Kazuo*

JAEA-Conf 2011-003, p.271 - 275, 2012/03

Japan Atomic Energy Agency (JAEA) is now developing a real time simulator for a material testing reactor in order to utilize a nuclear human resource development and promotion of partnership with developing countries which have a plan to introduce nuclear power plant and/or experimental research reactor. The simulator is scheduled to be operated in JFY2012. The simulator is based on Japan Materials Testing Reactor (JMTR), and treats most of JMTR, e.g. reactor, primary cooling system, secondary cooling system, emergency cooling system, instrumentation and control system, safety and protection systems and electricity system. It simulates normal operation condition, transient operation condition such as excess reactivity addition due to testing material insertion and condition of the LOCA. Moreover, it simulates an irradiation experiment using irradiation equipments such as material testing under BWR condition. The simulator is composed of a computer system, a console for reactor control, process control, irradiation equipments, and an instructor and large-size displays. The simulator has the control functions, such as load and store of initial conditions, selection of core conditions, control of execution (run/freeze/fast/slow), save of backtrack snapshots at regular intervals, etc. in order to increase education effects. Furthermore, it has actions, such as malfunctions, remote functions, global component failures, annunciator master control, etc.

JAEA Reports

Conceptual design of multipurpose compact research reactor; Annual report FY2010 (Joint research)

Imaizumi, Tomomi; Miyauchi, Masaru; Ito, Masayasu; Watahiki, Shunsuke; Nagata, Hiroshi; Hanakawa, Hiroki; Naka, Michihiro; Kawamata, Kazuo; Yamaura, Takayuki; Ide, Hiroshi; et al.

JAEA-Technology 2011-031, 123 Pages, 2012/01

JAEA-Technology-2011-031.pdf:16.08MB

The number of research reactors in the world is decreasing because of their aging. However, the planning to introduce the nuclear power plants is increasing in Asian countries. In these Asian countries, the key issue is the human resource development for operation and management of nuclear power plants after constructed them, and also the necessity of research reactor, which is used for lifetime extension of LWRs, progress of the science and technology, expansion of industry use, human resources training and so on, is increasing. From above backgrounds, the Neutron Irradiation and Testing Reactor Center began to discuss basic concept of a multipurpose low-power research reactor for education and training, etc. This design study is expected to contribute not only to design tool improvement and human resources development in the Neutron Irradiation and Testing Reactor Center but also to maintain and upgrade the technology on research reactors in nuclear power-related companies. This report treats the activities of the working group from July 2010 to June 2011 on the multipurpose low-power research reactor in the Neutron Irradiation and Testing Reactor Center and nuclear power-related companies.

Journal Articles

A Study to control chemical reactions using Si:2p core ionization; Site-specific fragmentation

Nagaoka, Shinichi*; Fukuzawa, Hironobu*; Pr$"u$mper, G.*; Takemoto, Mai*; Takahashi, Osamu*; Yamaguchi, Takuhiro*; Kakiuchi, Takuhiro*; Tabayashi, Kiyohiko*; Suzuki, Isao*; Harries, J.; et al.

Journal of Physical Chemistry A, 115(32), p.8822 - 8831, 2011/07

 Times Cited Count:29 Percentile:71.09(Chemistry, Physical)

JAEA Reports

Investigation on present status of thermal neutron scattering law for beryllium metal and hydrogen in light water

Imaizumi, Tomomi; Takemoto, Noriyuki; Nagao, Yoshiharu; Kawamura, Hiroshi

JAEA-Review 2009-074, 20 Pages, 2010/03

JAEA-Review-2009-074.pdf:4.11MB

For the neutronic calculation in JMTR, an error of only thermal-neutron-flux tends to extend in specific region, i.e. an irradiation region in beryllium reflectors surrounding the fuel region. From our former investigation, the reason is thought to be the neutron scattering and absorption in the thermal energy region. Therefore, the effect on the thermal neutron scattering law S($$alpha$$,$$beta$$) to hydrogen in light water and to beryllium metal was investigated. As a result, it was confirmed that the error could be caused by the treatment in inelastic scattering within coherent scattering in the beryllium metal, whereas no error factor was found to the hydrogen in light water.

Oral presentation

Hydrogen production with high-temperature gas-cooled reactors, 4; R&D on on-line measuring instruments for IS process

Takemoto, Jumpei; Yoshino, Koji*; Imai, Yoshiyuki; Kubo, Shinji; Kasahara, Seiji; Takahashi, Toshio*; Hino, Ryutaro

no journal, , 

no abstracts in English

Oral presentation

Design of low $$gamma$$ heating field in JMTR

Imaizumi, Tomomi; Takemoto, Noriyuki; Nagao, Yoshiharu

no journal, , 

The renewed and upgraded JMTR will start from FY 2011. The JMTR will be use to irradiation test about lifetime extension of light water reactors (LWRs), progress of science and technology, and expansion of industry use. To lifetime extension of LWRs, it is demanded the irradiation test to confirm integrity of reactor structural materials such as stainless steel and concrete, etc. In irradiation tests of concrete sample, it is necessary to keep low irradiation temperature to prevent dehydration of cement hydrates or thermal stress. However, irradiation samples are heated by $$gamma$$ rays. On the other hand, neutron irradiation test in low $$gamma$$ heating field is effective as progress of science and technology such as materials basic research. Therefore, the neutron irradiation field of low $$gamma$$ heating rate was designed in JMTR. In this study, it was considered that the $$gamma$$ heating rate is below 0.07 W/g in the JMTR core so as not to become higher temperature as planned.

Oral presentation

Oral presentation

Current status towards JMTR reoperation

Izumo, Hironobu; Imaizumi, Tomomi; Takemoto, Noriyuki; Hori, Naohiko

no journal, , 

no abstracts in English

Oral presentation

Status of neutronic evaluation in JMTR

Takemoto, Noriyuki; Kimura, Nobuaki; Imaizumi, Tomomi; Hori, Junichi*; Sano, Tadafumi*; Nakajima, Ken*

no journal, , 

no abstracts in English

14 (Records 1-14 displayed on this page)
  • 1