Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 27

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

Incorporation of U, Pb and rare earth elements in calcite through crystallisation from amorphous calcium carbonate; Simple preparation of reference materials for microanalysis

Miyajima, Yusuke*; Saito, Ayaka*; Kagi, Hiroyuki*; Yokoyama, Tatsunori; Takahashi, Yoshio*; Hirata, Takafumi*

Geostandards and Geoanalytical Research, 45(1), p.189 - 205, 2021/03

 Times Cited Count:2 Percentile:28.61(Geochemistry & Geophysics)

Uncertainty for elemental and isotopic analyses of calcite by LA-ICP-MS is largely controlled by the homogeneity of the reference materials (RMs) used for normalization and validation. In order to produce calcite RMs with homogeneous elemental and isotopic compositions, we incorporated elements including U, Pb, and rare earth elements into calcite through heat- and pressure-induced crystallization from amorphous calcium carbonate that was precipitated from element-doped reagent solution. X-ray absorption spectra showed that U was present as U(VI) in the synthesized calcite, probably with a different local structure from that of aqueous uranyl ions. The uptake rate of U by our calcite was higher in comparison to synthetic calcite of previous studies. Variations of element mass fractions in the calcite were better than 12% 2RSD, mostly within 7%. The $$^{207}$$Pb/$$^{206}$$Pb ratio in the calcite showed $$<$$1% variations, while the $$^{238}$$U/$$^{206}$$Pb ratio showed 3-24% variations depending on element mass fractions. Using the synthetic calcite as primary RMs, we could date a natural calcite RM, WC-1, with analytical uncertainty as low as $$<$$3%. The method presented can be useful to produce calcite with controlled and homogeneous element mass fractions, and is a promising alternative to natural calcite RMs for U-Pb geochronology.

JAEA Reports

Research on engineering technology in the full-scale demonstration of EBS and operation technology for HLW disposal; Research report in 2014 (Joint research)

Kobayashi, Masato*; Saito, Masahiko*; Iwatani, Takafumi*; Nakayama, Masashi; Tanai, Kenji; Fujita, Tomo; Asano, Hidekazu*

JAEA-Research 2015-018, 14 Pages, 2015/12

JAEA-Research-2015-018.pdf:5.43MB

JAEA and RWMC concluded the letter of cooperation agreement on the research and development of radioactive waste disposal in April, 2005, and have been carrying out the collaboration work based on the agreement. JAEA have been carrying out the Horonobe URL Project which is intended for a sedimentary rock in the Horonobe town, Hokkaido, since 2001. In the project, geoscientific research and research and development on geological disposal technology are being promoted. Meanwhile, The Agency for Natural Resources and Energy, Ministry of Economy, Trade and Industry has been promoting construction of equipments for the full-scale demonstration of engineered barrier system and operation technology for high-level radioactive waste disposal since 2008, to enhance public's understanding to the geological disposal of HLW, e.g. using underground facility. RWMC received an order of the project in fiscal year 2014 continuing since fiscal year 2008. Since topics in this project are included in the Horonobe URL Project, JAEA carried out this project as collaboration work continuing since fiscal year 2008. This report summarizes the results of the research on engineering technology carried out in this collaboration work in fiscal year 2014.

Journal Articles

Unconventional scaling and significant enhancement of the spin Seebeck effect in multilayers

Ramos, R.*; Kikkawa, Takashi*; Aguirre, M.*; Lucas, I.*; Anad$'o$n, A.*; Oyake, Takafumi*; Uchida, Kenichi*; Adachi, Hiroto; Shiomi, Junichiro*; Algarabel, P. A.*; et al.

Physical Review B, 92(22), p.220407_1 - 220407_5, 2015/12

 Times Cited Count:62 Percentile:91.8(Materials Science, Multidisciplinary)

Journal Articles

Enhancement of anomalous Nernst effects in metallic multilayers free from proximity-induced magnetism

Uchida, Kenichi*; Kikkawa, Takashi*; Seki, Takeshi*; Oyake, Takafumi*; Shiomi, Junichiro*; Qiu, Z.*; Takanashi, Koki*; Saito, Eiji

Physical Review B, 92(9), p.094414_1 - 094414_6, 2015/09

 Times Cited Count:66 Percentile:92.43(Materials Science, Multidisciplinary)

Journal Articles

Comparative study of granitic and sedimentary groundwater colloids by flow-field flow fractionation coupled with ICP-MS

Saito, Takumi; Hamamoto, Takafumi*; Mizuno, Takashi; Iwatsuki, Teruki; Tanaka, Satoru*

Journal of Analytical Atomic Spectrometry, 30(6), p.1229 - 1236, 2015/06

 Times Cited Count:12 Percentile:63.71(Chemistry, Analytical)

Size distribution and elemental compositions of colloids in granitic and sedimentary deep groundwater was determined by flow field flow fractionation (Fl-FFF) combined with ICP-MS. In the granitic groundwater organic colloids and various inorganic elements were found in limited size ranges ($$<$$10 nm and $$>$$140 nm). The presence of different types of organic colloids was suggested in this groundwater. Most of the inorganic elements exhibited similar size distributions at $$<$$10 nm, which were largely overlapped with organic colloids rich in fluorophores. In the sedimentary groundwater small organic and probably inorganic colloids were found at $$<$$5 nm together with relatively large inorganic colloids. Organic colloids in this groundwater were homogeneous in terms of their sizes and the compositions of chromohores and fluorophores. The size distribution of inorganic elements depended on their types, indicating the presence of different host colloidal phases for them.

Journal Articles

Visualization of blurry images of liquid by multi-scale analysis

Miyamura, Hiroko; Kureta, Masatoshi; Segawa, Mariko; Kubo, Jun*; Saito, Takafumi*; Suzuki, Yoshio; Takemiya, Hiroshi

Visualization of Mechanical Processes (Internet), 1(3), 8 Pages, 2011/10

The use of high frame rate neutron radiography has been proposed as a method for recording images of oil in a running car engine. However, it is difficult to capture the behavior of oil from such images, because the images are dark and blurry. Therefore, we attempt to overcome this problem using a multi-scale image processing technique, in which the oil regions are classified based on scale. This method can be used to focus attention on objects with a particular scale. In addition, we propose a technique by which to capture the time-dependent behavior of oil using spatio-temporal image analysis. Using these techniques, the region of interest can be determined and observed carefully.

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:164 Percentile:99.44(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

Visualization of blurred images of liquid by multi-scale analysis

Miyamura, Hiroko; Kureta, Masatoshi; Segawa, Mariko; Kubo, Jun*; Saito, Takafumi*; Suzuki, Yoshio; Takemiya, Hiroshi

Proceedings of 11th Asian Symposium on Visualization (ASV-11) (CD-ROM), 4 Pages, 2011/06

In this paper, we report that our image analysis technique, which has be proposed for analyzing large-scale and complex simulation and measurement experiment results in nuclear field was applied to the industrial problems. The Japan Atomic Energy Agency and Nissan Motor Co., Ltd. proposed a high-speed camera using neutron radiography, and developed the technology to capture the flow of oil in a car engine. However the recorded images are blurred, it is difficult to visualize and analyze the behavior of oil in detail. Therefore, we try to overcome this by using multi-scale analysis, which is an image processing technique on image emphasis. In addition, we present a spatio-temporal image analysis for capturing the behavior of oil that is not yet understood in detail. In this presentation, we discuss the effectiveness of our image analysis technique.

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:8 Percentile:51.82(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.

Journal Articles

Status of Japanese design and validation activities of test facilities in IFMIF/EVEDA

Wakai, Eiichi; Kikuchi, Takayuki; Kogawara, Takafumi; Kimura, Haruyuki; Yokomine, Takehiko*; Kimura, Akihiko*; Nogami, Shuhei*; Kurishita, Hiroaki*; Saito, Masahiro*; Nishimura, Arata*; et al.

Proceedings of 23rd IAEA Fusion Energy Conference (FEC 2010) (CD-ROM), 6 Pages, 2011/03

Japanese activities of test facilities in IFMIF-EVEDA (International Fusion Materials Irradiation Facility-Engineering Validation and Engineering Design Activities) project have three subjects of engineering design of post irradiation examination (PIE) facilities, small specimen test technique (SSTT), and engineering design of high flux test module (HFTM), and this paper is summarized about present status. Functional analysis and design of 2-D and 3-D models of PIE facility were performed. In HFTM, as materials of heater, W-3Re alloy and/or SiC/SiC composite were selected in the points of high temperature materials, fabrication technology and some suitable properties such as resistance of thermal shock, high temperature re-crystallization, ductility, resistance of irradiation degradation, and low-activation. In SSTT, a test machine of fracture toughness was designed and developed for small specimens with 10 mm square, and it had high accuracy controllability for stress and displacement.

JAEA Reports

Development of mechanical coupled analysis technique for the long term behavior of the near field, 2

Saito, Yuya; Tanai, Kenji; Takaji, Kazuhiko*; Shigeno, Yoshimasa*; Shimogochi, Takafumi*

JAEA-Research 2009-065, 76 Pages, 2010/03

JAEA-Research-2009-065.pdf:23.92MB

The 3-D mechanical coupled analysis technique for the long term mechanical behavior of near field is developed. The object of analysis is extended to the disposal gallery and the near field rock, in addition to the buffer material and the overpack for previous one. The analysis model is developed with a degradation model of concrete support and modeling of the near field rock with the valuable- compliance-type constitutive equation. The remaining problems of current study are related to; (1) mechanical property and modeling of backfill material, (2) adopting a degradation model of concrete support in the prototype model, (3) examining the effect of analytical model mesh and time step for the 3-D mechanical coupled analysis. We conducted the one-dimensional consolidation test for the backfill material. The backfill material shows a similar behavior to that of buffer material. And the prototype model is developed adopting a degradation model for a concrete support and examining the effect of the model mesh and time step.

Journal Articles

Visualization for atomizing liquid by using multi scale analysis

Miyamura, Hiroko; Kureta, Masatoshi; Segawa, Mariko; Kubo, Jun*; Saito, Takafumi*; Suzuki, Yoshio; Takemiya, Hiroshi

Denki Gakkai Kenkyukai Shiryo, Sangyo Keisoku Seigyo Kenkyukai (IIC-10-73), p.7 - 12, 2010/03

An experiment is conducted to measure the water and oil in a metallic object by neutron radiography. In this approach, visualization of the oil in a rotating car engine at high speed is achieved by using the proposed high-speed camera. However, because the oil is mist and liquid, it is difficult to identify these conditions and to analyze them. Therefore, we try to identify the oil condition in the engine by employing a multi-scale analysis, which is an image processing technique.

Journal Articles

Observation of itinerant Ce 4$$f$$ electronic states in CeIrSi$$_3$$ studied by angle-resolved Ce 3$$drightarrow 4f$$ resonance photoemission spectroscopy

Okochi, Takuo*; Toshimitsu, Takafumi*; Yamagami, Hiroshi; Fujimori, Shinichi; Yasui, Akira; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi; Miyauchi, Yuichiro*; et al.

Journal of the Physical Society of Japan, 78(8), p.084802_1 - 084802_6, 2009/08

 Times Cited Count:9 Percentile:53.38(Physics, Multidisciplinary)

We have applied angle-resolved Ce 3$$d{rightarrow}$$4$$f$$ resonance photoemission spectroscopy to the non-centrosymmetric pressure-induced superconductor CeIrSi$$_3$$ and obtained the 4$$f$$ band-structure and Fermi surfaces. We have found that the Ce 4$$f$$ states are located mainly near the Fermi level and that the photoemission intensity derived from the dispersive conduction bands across the Fermi level shows considerable resonant enhancement. In addition, the band structure and Fermi surfaces of CeIrSi$$_3$$ are different from those of the non-$$f$$ reference compound, LaIrSi$$_3$$ and the difference is well explained by the band structure calculated within the local density approximation (LDA). These results strongly suggest that the Ce 4$$f$$ electrons in CeIrSi$$_3$$ are well hybridized with conduction bands and form itinerant electronic states.

Journal Articles

Inspection techniques in reactor vessel of sodium cooled fast reactor

Itagaki, Wataru; Saito, Takakazu; Imaizumi, Kazuyuki; Nagai, Akinori; Aoyama, Takafumi; Maeda, Yukimoto

Dai-14-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu, p.435 - 438, 2009/06

no abstracts in English

JAEA Reports

Probabilistic safety assessment on experimental fast reactor Joyo; Level1 PSA for internal events

Ishikawa, Koki; Takamatsu, Misao; Kawahara, Hirotaka; Mihara, Takatsugu; Kurisaka, Kenichi; Terano, Toshihiro; Murakami, Takanori; Noritsugi, Akihiro; Iseki, Atsushi; Saito, Takakazu; et al.

JAEA-Technology 2009-004, 140 Pages, 2009/05

JAEA-Technology-2009-004.pdf:2.0MB

Probabilistic safety assessment (PSA) has been applied to nuclear plants as a method to achieve effective safety regulation and safety management. In order to establish the PSA standard for fast breeder reactor (FBR), the FBR-PSA for internal events in rated power operation is studied by Japan Atomic Energy Agency (JAEA). The level1 PSA on the experimental fast reactor Joyo was conducted to investigate core damage probability for internal events with taking human factors effect and dependent failures into account. The result of this study shows that the core damage probability of Joyo is 5.0$$times$$10$$^{-6}$$ per reactor year (/ry) and that the core damage probability is smaller than the safety goal for existed plants (10 ry) and future plants (10$$^{-5}$$/ry) in the IAEA INSAG-12 (International Nuclear Safety Advisory Group) basic safety principle.

Journal Articles

Visualization of runtime behavior of branch-and-bound algorithms

Miyamura, Hiroko; Shinano, Yuji*; Miyashiro, Ryuhei*; Saito, Takafumi*

Joho Shori Gakkai Rombunshi; Suri Moderuka To Oyo (Internet), 2(2), p.103 - 112, 2009/03

In branch-and-bound algorithms for integer programming, runtime behavior of the algorithms depends much on branching strategy. However, from a huge computation log of a large program, it is difficult to explore a key factor for effective branching. To analyze which factor of branching strategy is essential, we develop a system for visualization of growing process of a large branch-and-bound tree. The proposed system provides intuitive understanding how branching strategy affects branch-and-bound process.

Journal Articles

A New type of neptunyl(VI) hydroxide which is topologically similar to $$alpha$$-UO$$_{2}$$(OH)$$_{2}$$

Nakada, Masami; Kitazawa, Takafumi*; Saito, Takashi*; Wang, J.*; Takeda, Masuo*; Yamashita, Toshiyuki; Saeki, Masakatsu

Bulletin of the Chemical Society of Japan, 76(7), p.1375 - 1378, 2003/07

 Times Cited Count:5 Percentile:26.42(Chemistry, Multidisciplinary)

no abstracts in English

Oral presentation

Electronic structure of CeIrSi$$_3$$ studied by angle-resolved resonant photoemission spectroscopy

Toshimitsu, Takafumi; Okochi, Takuo; Yasui, Akira; Kobayashi, Masaki*; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi*; Yamagami, Hiroshi*; Miyauchi, Yuichiro*; et al.

no journal, , 

We performed angle-resolved resonant photoemission spectroscopy on CeIrSi$$_3$$. CeIrSi$$_3$$ is said to be the superconductor which lacks inversion symmetry and therefore the measurements of electronic conductivity, magnetoresistance, dHvA, and so on, have been made on so far. In this study, we observed extremely clear 4$$f$$ derived band dispersions and Fermi surfaces. By these obtained profiles and comparison with those predicted by LDA calculation, Ce 4$$f$$ electrons in CeIrSi$$_3$$ have relatively itinerant electronic states.

Oral presentation

Band structures of UIr and UGe$$_{2}$$ studied by angle-resolved soft X-ray photoemission spectroscopy

Okochi, Takuo; Fujimori, Shinichi; Toshimitsu, Takafumi; Okane, Tetsuo; Saito, Yuji; Fujimori, Atsushi*; Yamagami, Hiroshi*; Haga, Yoshinori; Yamamoto, Etsuji; Ikeda, Shugo; et al.

no journal, , 

We investigated the temperature dependence of the density of states and the band structure of ferromagnetic uranium compound, UIr, by the soft X-ray angle integrated / resolved photoemission spectroscopy. We observed the exchange splitting of the density of states as well as the representative 5${it f}$ band. These results suggest that the ferromagnetism of UIr is well explained by the Stoner model (itinerant-magnetism model).

Oral presentation

Temperature dependence in the band structures of UIr, UGe$$_{2}$$ studied by angle-resolved photoemisson spectroscopy

Okochi, Takuo; Fujimori, Shinichi; Toshimitsu, Takafumi; Okane, Tetsuo; Saito, Yuji; Yamagami, Hiroshi; Fujimori, Atsushi; Haga, Yoshinori; Yamamoto, Etsuji; Ikeda, Shugo; et al.

no journal, , 

no abstracts in English

27 (Records 1-20 displayed on this page)