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Journal Articles

High-temperature antiferromagnetism in Yb based heavy fermion systems proximate to a Kondo insulator

Suzuki, Shintaro*; Takubo, Ko*; Kuga, Kentaro*; Higemoto, Wataru; Ito, Takashi; Tomita, Takahiro*; Shimura, Yasumichi*; Matsumoto, Yosuke*; Bareille, C.*; Wadachi, Hiroki*; et al.

Physical Review Research (Internet), 3(2), p.023140_1 - 023140_12, 2021/05

We report our experimental discovery of the transition temperature reaching 20 K in a Yb-based compound at ambient pressure. The Mn substitution at the Al site in an intermediate valence state of $$alpha$$-YbAlB$$_4$$ not only induces antiferromagnetic transition at a record high temperature of 20 K but also transforms the heavy-fermion liquid state in $$alpha$$-YbAlB$$_4$$ into a highly resistive metallic state proximate to a Kondo insulator.

JAEA Reports

Performance confirmation operation of water environment control facility

Magome, Hirokatsu; Okada, Yuji; Tomita, Kenji; Iida, Kazuhiro; Ando, Hitoshi; Yonekawa, Akihisa; Ueda, Haruyasu; Hanawa, Hiroshi; Kanno, Masaru; Sakuta, Yoshiyuki

JAEA-Technology 2015-025, 100 Pages, 2015/09

JAEA-Technology-2015-025.pdf:78.32MB

In Japan Atomic Energy Agency, in order to solve the problem in the long-term operation of a light water reactor, preparation which does the irradiation experiment of light-water reactor fuel and material was advanced. JMTR stopped after the 165th operation cycle in August 2006, and is advancing renewal of the irradiation facility towards re-operation. The material irradiation test facility was installed from 2008 fiscal year to 2012 fiscal year in JMTR. The material irradiation test facility is used for IASCC study, and that consists of mainly three equipments. This report is described performance operating test of the water environmental control facilities for IASCC study carried out 2013 fiscal year.

Journal Articles

Nitric oxide-mediated bystander signal transduction induced by heavy-ion microbeam irradiation

Tomita, Masanori*; Matsumoto, Hideki*; Funayama, Tomoo; Yokota, Yuichiro; Otsuka, Kensuke*; Maeda, Munetoshi*; Kobayashi, Yasuhiko

Life Sciences in Space Research, 6, p.36 - 43, 2015/07

A radiation-induced bystander response is generally known as a cellular response induced in unirradiated cell by receiving bystander signaling factors released from directly irradiated cells of a cell population. Bystander responses induced by high-LET heavy ions at low fluence are an important problem concerning the health of astronauts in the space environment. Here we set out NO-mediated bystander signal transductions induced by high-LET heavy-ion microbeam irradiation in normal human fibroblasts. Our findings suggest that Akt- and NF-$$kappa$$B-dependent signaling pathway involving COX-2 plays an important role in the NO-mediated high-LET heavy-ion-induced bystander responses. Additionally, COX-2 may be used as a molecular marker of high-LET heavy-ion-induced bystander cells, which are distinguish form directly irradiated cells.

Journal Articles

Mechanisms for the induction of radioadaptive response by radiation-induced bystander response

Matsumoto, Hideki*; Tomita, Masanori*; Otsuka, Kensuke*; Hatashita, Masanori*; Maeda, Munetoshi*; Funayama, Tomoo; Yokota, Yuichiro; Suzuki, Michiyo; Sakashita, Tetsuya; Ikeda, Hiroko; et al.

JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 76, 2015/03

The objective of this project is to elucidate molecular mechanisms for the induction of radioadaptive response through radiation-induced bystander responses induced by irradiation with heavy ion microbeams in JAEA. We found that the adaptive response was induced by Ar (520 MeV $$^{40}$$Ar$$^{14+}$$) microbeam-irradiation of a limited number of cells, followed by the broad beam-irradiation and that the adaptive response was almost completely suppressed by the addition of carboxy-PTIO, as a nitric oxide (NO) scavenger. In addition, we found several genes induced specifically and preferentially when radioadaptive response could be induced. We confirmed that ${it iNOS}$ expression was specifically induced only when radioadaptive response could be induced. Our findings strongly suggested that radioadaptive response can be induced by NO-mediated bystander responses evoked by irradiation with heavy ion microbeams.

Journal Articles

Analysis of bystander response in 3D cultured tissue induced by heavy-ion microbeam irradiation

Tomita, Masanori*; Matsumoto, Hideki*; Otsuka, Kensuke*; Funayama, Tomoo; Yokota, Yuichiro; Suzuki, Michiyo; Sakashita, Tetsuya; Kobayashi, Yasuhiko

JAEA-Review 2014-050, JAEA Takasaki Annual Report 2013, P. 77, 2015/03

Radiation-induced bystander responses are defined as responses in cells that have not been directly targeted by radiation but are in the neighborhood of cells that have been directly exposed. In this study, we aim to clarify a role of bystander response to sustain the homeostasis of damaged tissue using heavy-ion microbeams. We established the heavy-ion microbeam irradiation method to a 3D cultured human epidermis. Using this method, a viable cell rate of the 3D cultured human epidermis irradiated with 260 MeV $$^{20}$$Ne-ion microbeams or broadbeams was analyzed by the MTT method.

JAEA Reports

Development of remote controlled electron probe micro analyzer with crystal orientation analyzer

Honda, Junichi; Matsui, Hiroki; Harada, Akio; Obata, Hiroki; Tomita, Takeshi

JAEA-Technology 2012-022, 35 Pages, 2012/07

JAEA-Technology-2012-022.pdf:3.58MB

The advanced utilization of Light Water Reactor (LWR) fuel is progressed in Japan to save the power generating cost and the volume of nuclear wastes. The electric power companies have been continued the approach to extend the burnup and to rise up the thermal power of the commercial fuel. The government should be accumulating the detailed information of the newest technologies to make the regulations and guidelines for the safety of the advanced nuclear fuels. The remote controlled Electron Prove Micro Analyzer attached with crystal orientation analyzer (EPMA) has been developed in Japan Atomic Energy Agency (JAEA) to evaluate the fuel behavior effected by the cladding microstructure under the accident condition. The device was modified to the airtight and earthquake resistant structure for the examination of high radioactive elements. This paper describes the specification of EPMA and the test results of the cold mock-up to confirm their performances and reliabilities.

JAEA Reports

Development of remote controlled ion milling device

Honda, Junichi; Matsui, Hiroki; Harada, Akio; Obata, Hiroki; Tomita, Takeshi

JAEA-Technology 2012-021, 17 Pages, 2012/07

JAEA-Technology-2012-021.pdf:4.17MB

The advanced utilization of Light Water Reactor (LWR) fuel is progressed in Japan to save the power generating cost and the volume of nuclear wastes. The electric power companies have been continued the approach to extend the burnup and to rise up the thermal power of the commercial fuel. The government should be accumulating the detailed information of the newest technologies to make the regulations and guidelines for the safety of the advanced nuclear fuels. The ion milling for post irradiation examination has been developed in Japan Atomic Energy Agency (JAEA) to investigate cladding microstructure. This device has been modified to operate the high radioactive elements remotely and have the performance of earthquake resistant. This paper describes the specification of the device which were specialized for post irradiation examination and the test results of the cold mock-up to confirm their performances and reliabilities.

JAEA Reports

Fabrication study of new irradiation facility for $$^{99}$$Mo production in JMTR

Takita, Kenji; Iimura, Koichi; Tomita, Kenji; Endo, Yasuichi; Kanno, Masaru

JAEA-Technology 2012-006, 41 Pages, 2012/03

JAEA-Technology-2012-006.pdf:6.8MB

At JAEA Oarai Research and Developnment Establishment (JAEA Oarai), JAEA Oarai was proceeding a plan to repair JMTR, which is to re-operate in fiscal 2012. Additionally, as an effective utilizati of JMTR, JAEA Oarai is planning to manufacture $$^{99}$$Mo, which is a parent nuclide of $$^{99}$$Tc. $$^{99m}$$Tc is most commonly used as a radiopharmaceution in the field of nuclear medicine. Currently $$^{99}$$Mo supply is dependent only on foreign imports, so JAEA is aiming for working on partially manufacturing $$^{99}$$Mo domestically with industrial circles in Japan. In this article, this report described the choice and fabric of irradiathion facility named Hydraulic Rabbit Facility for manufacturing $$^{99}$$Mo, the technical study of fabrication technique.

Journal Articles

Status of the design and investigation for hydraulic rabbit irradiation facility

Takita, Kenji; Iimura, Koichi; Tomita, Kenji; Endo, Yasuichi; Kanno, Masaru

UTNL-R-0480, p.7_4_1 - 7_4_6, 2012/03

no abstracts in English

Journal Articles

Identified charged hadron production in $$p + p$$ collisions at $$sqrt{s}$$ = 200 and 62.4 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06

 Times Cited Count:176 Percentile:99.41(Physics, Nuclear)

Transverse momentum distributions and yields for $$pi^{pm}, K^{pm}, p$$, and $$bar{p}$$ in $$p + p$$ collisions at $$sqrt{s}$$ = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different $$sqrt{s}$$ collisions. We also present the scaling properties such as $$m_T$$ and $$x_T$$ scaling and discuss the mechanism of the particle production in $$p + p$$ collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.

Journal Articles

Azimuthal correlations of electrons from heavy-flavor decay with hadrons in $$p+p$$ and Au+Au collisions at $$sqrt{s_{NN}}$$ = 200 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.

Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04

 Times Cited Count:7 Percentile:49.81(Physics, Nuclear)

Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled $$p+p$$ collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to $$p+p$$ collisions.

JAEA Reports

Design of fuel transient test facility system

Hosokawa, Jinsaku; Iimura, Koichi; Ogawa, Mitsuhiro; Tomita, Kenji; Yamaura, Takayuki

JAEA-Technology 2010-018, 269 Pages, 2010/08

JAEA-Technology-2010-018.pdf:5.75MB

At Oarai Research and Development Center, Japan Atomic Energy Agency (JAEA) advances the plan of refurbishing Japan Materials Testing Reactor (JMTR) to start the operation in fiscal 2011. Fuel Transient Test Facility is scheduled to be set up as neutron irradiation test equipment of the light-water reactor fuel that uses JMTR after it operates again. The abnormal transition examination device is the irradiation facilities where the output sudden rise examination that makes the light-water reactor fuel an irradiation sample is done to use it to develop the safety evaluation technology and the damage influence evaluation technology of the light-water reactor fuel that reaches high burn-up. In this report, as for the system design, it is a summary to JMTR among detailed designs of the abnormal transition examination device of the installation schedule.

JAEA Reports

Replacement technology for front acrylic panels of a large-sized glove box using bag-in / bag-out method

Sakuraba, Naotoshi; Numata, Masami; Komiya, Tomokazu; Ichise, Kenichi; Nishi, Masahiro; Tomita, Takeshi; Usami, Koji; Endo, Shinya; Miyata, Seiichi; Kurosawa, Tatsuya; et al.

JAEA-Technology 2009-071, 34 Pages, 2010/03

JAEA-Technology-2009-071.pdf:21.07MB

As a part of maintenance technology of a large-sized glove box for handling of TRU nuclides, we developed replacement technology for front acrylic panels using the bag-in/bag-out method and applied this technology to replace the deteriorated front acrylic panels at Waste Safety Testing Facility (WASTEF) in Nuclear Science Research Institute of Japan Atomic Energy Agency (JAEA). As a consequence, we could safely replace the front acrylic panels under the condition of continuous negative pressure only with partial decontamination of the glove box. We also demonstrated that the present technology is highly effective in points of safety, workability and cost as compared to the usual replacement technology for front acrylic panels of a glove box, where workers in an air-line suit replace directly the front acrylic panels in a green house.

Journal Articles

Tritium science and technology for fusion reactor, 3; Theory and code development for evaluation of tritium retention and exhaust in fusion reactor

Oya, Kaoru*; Inai, Kensuke*; Shimizu, Katsuhiro; Takizuka, Tomonori; Kawashima, Hisato; Hoshino, Kazuo; Hatayama, Akiyoshi*; Toma, Mitsunori*; Tomita, Yukihiro*; Kawamura, Gakushi*; et al.

Purazuma, Kaku Yugo Gakkai-Shi, 85(10), p.695 - 703, 2009/10

no abstracts in English

Journal Articles

Replacement technique for front acrylic panels of a large size glove box using bag-in / bag-out method

Endo, Shinya; Numata, Masami; Ichise, Kenichi; Nishi, Masahiro; Komiya, Tomokazu; Sakuraba, Naotoshi; Usami, Koji; Tomita, Takeshi

Proceedings of 46th Annual Meeting of "Hot Laboratories and Remote Handling" Working Group (HOTLAB 2009) (CD-ROM), 6 Pages, 2009/09

For safety operation and maintenance of the large size glove box, the degraded acrylic panels of the box must be replaced by the new panels. As the conventional replacement technique, the decontamination of the glove box and installation of isolation tent are necessary to prevent the leak of contamination, because airtight condition of the box is broken down during replacement process. Therefore, the prerequisite works are required considerable manpower. The new replacement technique using bag-in / bag-out method was developed by JAEA. In this technique, for keeping the airtight condition of the box, the inside of degraded panel is covered with an airtight panel and the outside is covered over the large bag which is used to replace the acrylic panels. As the benefits of this technique, the prerequisite works are not required and the manpower is less than a third of the conventional technique.

JAEA Reports

Design study of the material irradiation facility for the SCC research under the LWR irradiation environment

Onuma, Yuichi; Tomita, Kenji; Okada, Yuji; Hanawa, Hiroshi

JAEA-Technology 2009-034, 79 Pages, 2009/07

JAEA-Technology-2009-034.pdf:11.23MB

Toward the re-operation of Japan Materials Testing Reactor on 2011 F.Y., the construction of new material irradiation facility for the stress corrosion cracking research under the LWR irradiation environment had been planed, and the design study of water control unit for BWR and water chemical study which supply the LWR simulated water to the material irradiation capsule were carried out on 2007 F.Y. The design study of new material irradiation facility was examined including the reflection of the operation experience and the reuse of components on old material irradiation facility. These examination results were summarized in this report.

JAEA Reports

Dose evaluation for fuel transient test

Iimura, Koichi; Ogawa, Mitsuhiro; Tomita, Kenji; Tobita, Masahiro

JAEA-Technology 2009-021, 71 Pages, 2009/05

JAEA-Technology-2009-021.pdf:4.34MB

The preparation of a fuel transient test using the JMTR is advanced to conduct its irradiation test from 2011 F.Y. after re-operation of the JMTR. The fuel behavior for high burn-up BWR's under power ramping condition will be evaluated in simulating the BWR environmental condition using the shroud irradiation facility (Oarai Shroud Facility No.1) and $$^{3}$$He power-control type BOCA (Boiling Water Capsule) irradiation facility, which is composed of the capsule control device, $$^{3}$$He power-control device and boiling water capsule. In order to change the fuel irradiation conditions so as to treat high burn-up fuels (from 50 GWD/t-UO$$_{2}$$ to 110 GWD/t-U), it is necessary to revaluate the dose for the safety evaluation at the test fuel failure. In this report, evaluations for equivalent dose rate of each device and exposure dose of handling operators when all fission products released in the coolant of the capsule control device and the BOCA at fuel failure in the fuel transient test are summarized.

JAEA Reports

Dose evaluation of external exposure by direct and skyshine gamma rays of nuclear fuel handling facilities at JMTR

Ogawa, Mitsuhiro; Iimura, Koichi; Tomita, Kenji; Tobita, Masahiro

JAEA-Technology 2009-017, 254 Pages, 2009/05

JAEA-Technology-2009-017.pdf:15.04MB

In JMTR, upgrade of irradiation facilities is advanced to re-operate from 2011 F.Y. In order to irradiate test fuels of high-burnup, external exposure reassessment by direct and skyshine gamma rays of the nuclear fuel handling facility at JMTR was performed. In evaluation method, radiation source of maximum use of the nuclear fuel was calculated by using ORIGEN2 code. Dose equivalent rate for supervised area boundary was calculated by modeling reactor building at using shielding calculation codes QAD-CGGP2 and G33-GP2. As a result of evaluation, it was confirmed that the effective dose equivalent during year was low enough at supervised area boundary of the JMTR site.

JAEA Reports

Renewal of tritium monitor of sweep gas apparatus

Tomita, Kenji; Inoue, Shuichi; Ishida, Takuya; Onuma, Yuichi; Tsuchiya, Kunihiko

JAEA-Technology 2008-050, 41 Pages, 2008/07

JAEA-Technology-2008-050.pdf:6.6MB

Blanket Functional Facility (BFT) for fusion blanket development was established in the Japan Materials Testing Reactor (JMTR). The irradiation tests with Li$$_{2}$$TiO$$_{3}$$ pebble-bed were carried out with the BFT. The BFT was constituted a sweep gas device for tritium measurement and recover and a capsule controlled device for temperature control and neutron flux measurement of Li$$_{2}$$TiO$$_{3}$$ pebble-bed. Five tritium monitors (ion chambers) for tritium measurement were established in the sweep gas device. In these tritium monitors, one tritium monitor for the measurement of tritium release property (TmIRA201) was not able to be used and it is necessary to exchange new tritium monitors. This report is described the fabrication of new tritium monitors and exchange procedure of this monitors.

JAEA Reports

Development of evaluation method on irradiation temperature for JMTR capsule; Temperature valuation of CT specimen and separated specimen holder by NISA FEM code

Tomita, Kenji; Hosokawa, Jinsaku; Matsui, Yoshinori

JAEA-Technology 2008-043, 21 Pages, 2008/07

JAEA-Technology-2008-043.pdf:9.2MB

In JMTR, highly precise-ization of irradiation temperature evaluation of material capsule is advanced towards re-operation in the 2011 fiscal year. In the conventional sub-program, rectangular form was loaded into the capsule and temperature evaluation was carried out. In this development, the CT specimen which is special form is loaded into capsule, and it enabled it to analyze a temperature distribution. Moreover, the sub-program which can also evaluate the heat stress distribution by this uneven temperature distribution was developed. And, in order to be able to perform easily extraction and re-load of irradiation specimens, the structure of separation specimen holder effective in a re-irradiation examination is adopted. However, with this structure, the inside of capsule serves as uneven temperature distribution. For this reason, the sub-program which can evaluate this temperature distribution was developed.

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