JAEA Abstracts

-Research results below have been sorted by order of journals name.

-Sorry, some research results below have no English abstract.

October 2008

36001257
Crystal-grain refinement of materials under an ultra-strong gravitational field
Iguchi, Yusuke*; Shibata, Yasuhiro*; Uchida, Yuta*; Huang, X.*; Ono, Masao; Okayasu, Satoru; Mashimo, Tsutomu
Advanced Materials Research 15-17, p.639-642(2007) ; (JAEA-J 04551)

In this study, we investigate the crystalline states and conditions for the grain-refinement of Bi₇₀Sb₃₀ alloy. It was considered under an ultra strong gravity field, the crystals were fine-grained from the primary grain sizes of several mm to several tens of mm, and the crystal growth followed with formation of graded-composition structure due to sedimentation of atoms along the direction of gravity. It was found that for the crystal-grain refinement in Bi₇₀Sb₃₀ alloy the minimum gravitational field and the minimum time duration were at least 160,000 G and 10 hours, respectively at about 200 °C.

36001258
Sedimentation of isotope atoms in monatomic liquid Se
Mashimo, Tsutomu; Ono, Masao; Huang, X. S.*; Iguchi, Yusuke*; Okayasu, Satoru; Kobayashi, Katsura*; Nakamura, Eizo*
Applied Physics Letters 91(23), p.231917_1-231917_3(2007) ; (JAEA-J 04552)

A strong gravitational field resulted in the sedimentation of isotope atoms in monatomic liquid. The concentration ratio ⁸²Se/⁷⁶Se increased by greater than 3.5% in specimen ultracentrifuged at 0.7∼0.9 million G and at 300°C. The recovered sample had a feather-shaped crystalline morphology. The concentration gradient was nearly twice that of the steady state analytical result (ideal gas system), indicating a non-ideal system diffusion. The present result is evidence of sedimentation of substitutional atoms in condensed matter via self-diffusion, and suggestes its possible application to isotope separation, crystalline control and matter dynamics in massive star.

36001259
Thermally activated charge transfer in a Prussian blue derivative probed by resonant inelastic X-ray scattering
Jarrige, I.; Cai, Y. Q.*; Ishii, Hirofumi*; Hiraoka, Nozomu*; Bleuzen, A.*
Applied Physics Letters 93(5), p.054101_1-054101_3(2008) ; (JAEA-J 04553)

Charge-transfer excitation is at the source of the photoinduced magnetism observed in several Prussian blue molecule-based magnets. Using resonant inelastic X-ray scattering and X-ray absorption spectroscopy, we probe directly the thermally-activated charge transfer in a photomagnetic Fe-Co cyanide, Cs_0.7Co₄[Fe(CN)₆]_2.9[V]_1.1. 16H₂O, where [V] represents [Fe(CN)₆] vacancies. The temperature dependence of both Co and Fe valence ratios is estimated for the first time in one cooling run, thus yielding a more complete picture of the temperature-induced cooperative electronic modifications. This novel approach, benefiting from relatively short acquisition times, opens the possibility for realtime characterization of the photoinduced magnetism in molecule-based magnets.

36001260
Validation of environmental transfer models and assessment of the effectiveness of countermeasures using data on ¹³¹I releases from Chernobyl
Krajewski, P.*; Ammann, M.*; Bartusková, M.*; Duffa, C.*; Filistovic, V.*; Homma, Toshimitsu; Kanyár, B.*; Malátová, I.*; `Nedveckaite, T.*; Simon, S.*; Vlasov, O.*; Webbe-Wood, D.*; Zvonova, I.*
Applied Radiation and Isotopes 66(11), p.1730-1735(2008) ; (JAEA-J 04554)

The studies undertaken by the ¹³¹I Working Group, part of the International Atomic Energy Agency's EMRAS (Environmental Modelling for Radiation Safety) programme, were focused primarily on evaluating the predictive capability of environmental models. Particular emphasis was placed on applying models to evaluate the effectiveness of countermeasures.

36001261
Surface structure and phase transition of Ge(111)-3×3-Pb studied by reflection high-energy positron diffraction
Fukaya, Yuki; Hashimoto, Mie; Kawasuso, Atsuo; Ichimiya, Ayahiko
Applied Surface Science 254(23), p.7827-7830(2008) ; (JAEA-J 04555)

36001262
Key interactions in integrin ectodomain responsible for global conformational change detected by elastic network normal-mode analysis
Matsumoto, Atsushi; Kamata, Tetsuji*; Takagi, Junichi*; Iwasaki, Kenji*; Yura, Kei
Biophysical Journal 95(6), p.2895-2908(2008) ; (JAEA-J 04556)

Protein is activated, but the activation mechanism and generality of the conformational change remain to be elucidated. We performed normal mode analysis of the elastic network model on integrin α_Vβ₃ ectodomain in the bent form and identified key residues which were influential on molecular motions. Iterative normal mode calculations demonstrated that the specific non-bonded interactions involving the key residues work as a snap to keep integrin in the bent form. The importance of the key residues for the conformational change was further verified by mutation experiments. Conservation pattern of amino acid residues among integrin family showed that the characteristic pattern of residues seen around these key residues is found in the limited groups of integrin β chains.

36001263
The Survival of heavy ion-irradiated Bcl-2 overexpressing radioresistant tumor cells and their progeny
Hamada, Nobuyuki*; Hara, Takamitsu*; Omura, Motoko*; Funayama, Tomoo; Sakashita, Tetsuya; Sora, Sakura*; Nakano, Takashi*; Kobayashi, Yasuhiko
Cancer Letters 268(1), p.76-81(2008) ; (JAEA-J 04557)

Here, we investigated the cell killing effectiveness of heavy-ion radiation in Bcl-2 overexpressing radioresistant tumor cells. First, irradiated cells underwent primary colony formation. Radioresistance decreased with increasing linear energy transfer (LET), indicating that heavy ions may be a promising therapeutic modality for Bcl-2 overexpressing tumors. Second, cells in primary colonies were reseeded for secondary colony formation. The incidence of delayed reproductive death increased with LET irrespective of Bcl-2 overexpression, suggesting that Bcl-2 overexpression may not facilitate heavy ion induced genomic instability.

36001264
Intense laser-induced decomposition of mass-selected 2-, 3-, and 4-methylaniline cations
Itakura, Ryuji; Tanaka, Takatsugu*; Kuwata, Mikinori*; Suzuki, Hideaki*; Yamanouchi, Kaoru*
Chemical Physics Letters 462(1-3), p.27-30(2008) ; (JAEA-J 04558)

Photodecomposition processes of 2-, 3-, and 4-methylaniline cations induced by a moderately intense (10¹¹ W/cm²) visible nanosecond laser field and an intense (10¹⁵W/cm²) UV femtosecond laser field are investigated using a tandem mass spectrometer. Highly unsaturated fragment cations such as C₆H₂⁺, C₆H₃⁺ are dominantly produced by the nanosecond laser, while less unsaturated smaller fragment cations such as C₃H₃⁺, C₄H₄⁺, C₅H₅⁺ are produced mainly by the femtosecond laser.

36001265
Conservative global gyrokinetic toroidal full-f five-dimensional Vlasov simulation
Idomura, Yasuhiro; Ida, Masato; Kano, Takuma; Aiba, Nobuyuki; Tokuda, Shinji
Computer Physics Communications 179(6), p.391-403(2008) ; (JAEA-J 04559)

A new conservative global gyrokinetic toroidal full-f five-dimensional Vlasov simulation (GT5D) is developed using a novel non-dissipative conservative finite difference scheme. The scheme guarantees numerical stability by satisfying relevant first principles in the modern gyrokinetic theory, and enables robust and accurate simulations of tokamak micro-turbulence. GT5D is verified through comparisons of zonal flow damping tests, linear analyses of ion temperature gradient driven (ITG) modes, and nonlinear ITG turbulence simulations against a global gyrokinetic toroidal δ f particle code. In the comparison, global solutions of the ITG turbulence are identified quantitatively by using two gyrokinetic codes based on particle and mesh approaches.

36001266
Status and perspective of the Nb₃Al development
Takeuchi, Takao*; Kikuchi, Akihiro*; Banno, Nobuya*; Kitaguchi, Hitoshi*; Iijima, Yasuo*; Tagawa, Kohei*; Nakagawa, Kazuhiko*; Tsuchiya, Kiyosumi*; Mitsuda, Shiori*; Koizumi, Norikiyo; Okuno, Kiyoshi
Cryogenics 48(7-8), p.371-380(2008) ; (JAEA-J 04560)

Nb₃Al has advantages of better tolerance to strain/stress and a higher critical magnetic field (30 T at 4.2 K) for stoichiometric composition over Nb₃Sn. The rapid-heating, quenching and transformation annealing (RHQT) process enables to form a stoichiometric Nb₃Al with fine grain structures via metastable bcc supersaturated-solid-solution. As a result a large critical current density of Nb₃Al is achieved over the whole range of magnetic fields without trading off the excellent strain tolerance. A long-length of RHQ processing has been established, and a rectangular but Cu stabilized Nb₃Al strand is about be commercially available for NMR uses. Ag or Cu internal stabilization and Cu ion-plating/electroplating techniques have been also developed to enable the stabilized round wire for accelerator and fusion magnets. Successfully energized test coils that were manufactured with a wind-and-react technique have demonstrated that a long piece of Cu stabilized RHQT Nb₃Al wire is really available for practical applications.

36001267
Extraction behavior of lanthanides using a diglycolamide derivative TODGA in ionic liquids
Shimojo, Kojiro; Kurahashi, Kensuke; Naganawa, Hirochika
Dalton Transactions 2008(37), p.5083-5088(2008) ; (JAEA-J 04561)

Liquid-liquid extraction of lanthanides from aqueous solutions into ionic liquids (ILs) has been investigated using N,N,N',N'-tetra(n-octyl)diglycolamide (TODGA) as an extractant, and compared with that in the isooctane system. Application of ILs as extracting phase provided unprecedented enhancement of the extraction performance of TODGA for lanthanides compared with that of the isooctane system. Slope analysis confirmed that TODGA in ILs formed a 1:3 complex with La³⁺, Eu³⁺, or Lu³⁺. On the other hand, the molar ratios of species extracted into isooctane were 1:3 for La³⁺ or 1:4 for Eu³⁺ and Lu³⁺, depending on the atomic number of lanthanides. The transfer of lanthanides with TODGA into ILs proceeded via a cation-exchange mechanism, in contrast to ion pair extraction in the isooctane system. Furthermore, we clarified that TODGA provided the selectivity for middle lanthanides in the ILs systems, but heavier lanthanides in the isooctane system.

36001268
Diffusion of ⁸Li short-lived radiotracer in Li ionic conductors of NaTl-type intermetallic compounds
Sugai, Hiroyuki; Sataka, Masao; Okayasu, Satoru; Ichikawa, Shinichi; Nishio, Katsuhisa; Mitsuoka, Shinichi; Nakanoya, Takamitsu; Osa, Akihiko; Sato, Tetsuya; Hashimoto, Takashi; Jeong, S. C.*; Katayama, Ichiro*; Kawakami, Hirokane*; Watanabe, Yutaka*; Ishiyama, Hironobu*; Imai, Nobuaki*; Hirayama, Yoshikazu*; Miyatake, Hiroari; Hashimoto, Takanori*; Yahagi, Masahito*
Defect and Diffusion Forum 273-276, p.667-672(2008) ; (JAEA-J 04562)

A non-destructive and on-line diffusion tracing in Li ionic conductors has been successfully conducted by using the short-lived α-emitting radiotracer of ⁸Li. The radiotracers produced as an energetic and pulsed ion beam are implanted into the Li ionic conductor of NaTl-type intermetallic compounds (β-LiAl, β-LiGa, and β-LiIn). The α-particles survived on their passage from the position emitted by the diffusing ⁸Li to the surface of the specimen are measured as a function of time. The diffusion coefficients of Li obtained for the NaTl-type intermetallic compounds with different Li compositions are quantitatively discussed in terms of the interaction between the structural defects in the specimen and Li.

36001269
Gravity-induced diffusion of isotope atoms in monoatomic solid Se
Mashimo, Tsutomu; Ono, Masao; Huang, X. S.*; Iguchi, Yusuke*; Okayasu, Satoru; Kobayashi, Katsura*; Nakamura, Eizo*
Europhysics Letters 81(5), p.56002_p1-56002_p4(2008) ; (JAEA-J 04563)

A strong gravitational field resulted in the gravity-induced diffusion (sedimentation) of isotope atoms in monoatomic solid Se. The layer crystalline morphology consisting of three zones of the fine-grained crystals, the long crystals and feather-shaped crystals grown parallel to gravity direction appeared in the specimen ultracentrifuged at 0.8-1 million G and at 190 °C. Change in concentration ratio ⁸²Se/⁷⁶Se of > 0.8% was observed in the grown crystalline region. These results show an evidence for sedimentation of substitutional atoms in solid via self-diffusion, and suggest possibility of application to control of impurity and crystalline state as well as to isotope separation.

36001270
Status of KSTAR electron cyclotron heating system
Bae, Y. S.*; Na, Y. S.*; Oh, Y. K.*; Kwon, M.*; Bak, J. S.*; Lee, G. S.*; Jeong, J. H.*; Park, S. I.*; Cho, M. H.*; Namkung, W.*; Ellis, R. A.*; Park, H.*; Sakamoto, Keishi; Takahashi, Koji; Yamamoto, Takumi
Fusion Science and Technology 52(2), p.321-333(2007) ; (JAEA-J 04564)

An 84-GHz, 500-kW gyrotron system have been installed at KSTAR, and the initial test of the gyrotron has been carried out with 20 μsec-pulse and an output RF power of 500 kW. The launcher system having with a highly flexible steering mirror was fabricated and would inject 500-kW rf power into the KSTAR plasma. KSTAR will employ 170-GHz EC current drive (CD) in ITER-relevant experiments such as the suppression of the neoclassical tearing modes and the creation of an electron internal transport barrier. A JAEA 170-GHz, 1-MW gyrotron on loan in accordance with a Korea-Japan fusion collaboration agreement, and it will be used for the 170-GHz, 1-MW ECCD system in 2010. This paper describes the current status of the installation and initial conditioning tests of the 84-GHz gyrotron system as well as the development plan of the 170-GHz ECH and CD system. Also, this paper discusses the CD efficiency and the steering range of the second-harmonic X-mode injection.

36001271
Transient behavior of gas entrainment caused by surface vortex
Ezure, Toshiki; Kimura, Nobuyuki; Hayashi, Kenji; Kamide, Hideki
Heat Transfer Engineering 29(8), p.659-666(2008) ; (JAEA-J 04565)

A compact sodium cooled reactor is one of important candidates as FBRs and has been investigated in the feasibility study of FBR cycle. According to the compact sizing of reactor vessel, gas entrainment at the free surface of sodium coolant becomes one of the significant issues for reactor design, and it is required to clarify the criterion of gas entrainment at free surface and the tolerance. In the present study, some visualization experiments were performed in a water-air system focusing on the gas entrainment due to surface vortex and its transient phenomena. Influences of horizontal velocity were clarified by the visualization. Time trends of circulation and length of gas core for the intermittent surface vortices were measured by the particle image velocimetry and visualization. It was found that the gas core length extends with time delay to the increase of circulation around the vortex.

36001272
Magnetic and dielectric properties of InFe₂O₄, InFeCuO₄, and InGaCuO₄
Yoshii, Kenji; Ikeda, Naoshi*; Okajima, Yuka; Yoneda, Yasuhiro; Matsuo, Yoji*; Horibe, Yoichi*; Mori, Shigeo*
Inorganic Chemistry 47(14), p.6493-6501(2008) ; (JAEA-J 04566)

The magnetic and dielectric properties of InFe₂O₄, InFeCuO₄and InGaCuO₄ have been investigated. All these materials areisostructural with RFe₂O₄ (R=Y, Ho-Lu), which shows ferroelectricity due to iron-valence ordering. InFe₂O₄ exhibits similar properties to those of RFe₂O₄; the origins of the magnetic and dielectric phenomena are likely common in InFe₂O₄ and RFe₂O₄. From measurements of the other two materials, we found that both the magnetic transition temperature and the dielectric constant are decreased in the order of InFe₂O₄, InFeCuO₄ and InGaCuO₄. This result strongly supports the previously reported explanation based on an electron transfer between the Fe-site ions for the corresponding rare-earth systems. Therefore, we propose that the dielectric properties of the oxides isostructural with RFe₂O₄ are plausibly governed by electron transfer; this situation is different from that of ordinary ferroelectrics and dielectrics, in which the displacement factions and anions is important. In addition, InFeCuO₄ and InGaCuO₄ exhibit large dielectric constants (larger than about 1500). Inconsideration of this property, the possible applications of these oxides are discussed.

36001273
Mechanisms of reduction in hole concentration in Al-implanted p-type 6H-SiC by 1 MeV electron irradiation
Matsuura, Hideharu*; Izawa, Keisuke*; Minohara, Nobumasa*; Oshima, Takeshi
Japanese Journal of Applied Physics 47(7), p.5355-5357(2008) ; (JAEA-J 04567)

The reduction in hole concentration (p) in Al-implanted p-type 6H-SiC due to 1 MeV electron irradiation was studied. By analysis of p, the acceptor density (N_A), its ionizing energy (E_A) and nature of the acceptor are determined. As a result, the acceptor observed in this study is assigned to an Al acceptor. E_A is independent of irradiation fluence (Φ), in spite that N_A is strongly dependent on Φ. We derived an analytical expression for the fluence dependence of N_A and we estimated the removal coefficient (i.e., removal cross-section) of N_A to be 6.4×10¹⁸ cm² for 1 MeV electron irradiation. The reduction in p due to electron irradiation is found to be mainly due to the decrease in N_A, not to the increase in the density of defects with deep-level, because the decrease in N_A is much larger than the increment in the density of deep-level defects.

36001274
Phase-contrast imaging of nanostructures by soft X rays from a femtosecond-laser plasma
Gasilov, S. V.*; Faenov, A. Y.; Pikuz, T. A.*; Skobelev, I. Yu.*; Calegari, F.*; Vozzi, C.*; Nisoli, M.*; Sansone, G.*; Valentini, G.*; De Silvestri, S.*; Stagira, S.*
JETP Letters 87(5), p.238-242(2008) ; (JAEA-J 04568)

The possibility of phase-contrast imaging of nanostructures has been analyzed with the use of solid targets irradiated by femtosecond laser pulses as a spatially coherent soft X-ray source and a LiF crystal as an X-ray detector having both the submicron spatial resolution in a wide field of view and a high contrast. It has allowed to obtain high-quality phase-contrast X-ray images of foils with various chemical compositions and a thickness of about 100 nm.

36001275
Development of a land surface model including cloud water deposition on vegetation
Katata, Genki; Nagai, Haruyasu; Wrzesinsky, T.*; Klemm, O.*; Eugster, W.*; Burkard, R.*
Journal of Applied Meteorology and Climatology 47(8), p.2129-2146(2008) ; (JAEA-J 04569)

A land surface model including cloud water deposition to vegetation was developed to better predict water exchanges between biosphere and atmosphere. High performance of our new model was confirmed and it provided a better prediction of measured cloud water flux than the commonly used model. Simple linear relationships between wind speed and deposition velocity (V_dep) were found. Numerical experiments were performed to study the influences of leaf shapes (needle and broad leaves) and canopy structure (Leaf area index (LAI) and canopy height) on V_dep. Broad leaves with small sized leaves can capture larger amounts of cloud water than needle leaves. >From the analyses of conductances at given Leaf Area Density (LAD), we found that trees whose LAD ≈ 0.1 m² m^-3 are the most efficient structures for cloud water deposition. A simple expression for the slope of V_dep against LAD obtained from the experiments can be useful to predict cloud water deposition.

36001276
Preparation of polymer electrolyte membranes consisting of alkyl sulfonic acid for a fuel cell using radiation grafting and subsequent substitution/elimination reactions
Takahashi, Shuichi*; Okonogi, Hiroyuki*; Hagiwara, Tokio*; Maekawa, Yasunari
Journal of Membrane Science 324(1-2), p.173-180(2008) ; (JAEA-J 04571)

Polymer electrolyte membranes (PEM) consisting of alkylsulfonic acid were successfully synthesized by radiation-induced graft polymerization of methyl acrylate (MA) into a poly(ethylene-co-tetrafluoroethylene) (ETFE) film, followed by sulfonation at an α-carbonyl carbon of the MA units in the grafting chain using an equimolar complex of chlorosulfonic acid and dioxane (ClSO₃H-Complex). The ion exchange capacity and ion conductivity of the MA-grafted PEM were controlled in the respective ranges of 0.54-1.47 mmol/g and 0.014-0.14 S/cm by changing the grafting degree. It has been confirmed by titrimetric and gravimetric analyses of sulfonic and carboxylic acids in the film that the sulfonation reaction is accompanied with decarboxylation of the MA units equimolar to the substituted sulfonic acids (substitution of carboxylic acid with sulfonic acid), that the sulfonation degree was about 30%.

36001277
Cavitation damage prediction for spallation target vessels by assessment of acoustic vibration
Futakawa, Masatoshi; Kogawa, Hiroyuki; Hasegawa, Shoichi; Ikeda, Yujiro; Riemer, B.*; Wendel, M.*; Haines, J.*; Bauer, G.*; Naoe, Takashi; Okita, Kohei*; Fujiwara, Akiko*; Matsumoto, Yoichiro*; Tanaka, Nobuatsu*
Journal of Nuclear Materials 377(1), p.182-188(2008) ; (JAEA-J 04572)

36001278
In-core SCC growth behavior of type 304 stainless steel in BWR simulated high-temperature water at JMTR
Kaji, Yoshiyuki; Ugachi, Hirokazu; Tsukada, Takashi; Nakano, Junichi; Matsui, Yoshinori; Kawamata, Kazuo; Shibata, Akira; Omi, Masao; Nagata, Nobuaki*; Dozaki, Koji*; Takiguchi, Hideki*
Journal of Nuclear Science and Technology 45(8), p.725-734(2008) ; (JAEA-J 04573)

Irradiation assisted stress corrosion cracking (IASCC) is one of the critical concerns when stainless steel components have been in service in light water reactors for a long period. In-core IASCC growth tests have been carried out using the compact tension type specimens of type 304 stainless steel that had been pre-irradiated up to a neutron fluence level around 1×10²⁵n/m² in pure water simulated boiling water reactor (BWR) coolant condition at the Japan Materials Testing Reactor (JMTR). In order to investigate the effect of synergy of neutron/γ radiation and stress/water environment on IASCC growth rate, we performed ex-core IASCC tests on irradiated specimens at several dissolved oxygen contents environments under the same electrochemical potential condition. In this paper, results of the in-core SCC growth tests will be discussed and compared with the result obtained by ex-core tests from a viewpoint of the synergistic effects on IASCC.

36001279
Calculation of neutron cross sections on ⁹³Nb for JENDL-4
Ichihara, Akira; Kunieda, Satoshi; Shibata, Keiichi
Journal of Nuclear Science and Technology 45(8), p.793-801(2008) ; (JAEA-J 04574)

Nuclear data of ⁹³Nb in JENDL-3.3 were reexamined in the incident neutron energy range from 10 keV to 20 MeV toward JENDL-4. Cross sections, differential and double-differential cross sections were calculated on the basis of the nuclear reaction models such as the spherical optical model, the distorted wave Born approximation, the Kalbach preequilibrium model, and the Hauser-Feshbach statistical model. It was found that experimental neutron emission spectra were reproduced well by the present calculation compared with the JENDL-3.3 evaluations for emission energies > 1 MeV. Calculated cross sections are almost consistent with the experimental data for total, elastic and inelastic scattering, (n,γ), (n,3n), (n,Xp), (n,Xd), (n,t), (n,α), (n,nα) and (n,Xα) reactions. An appreciable change from the JENDL-3.3 evaluation was not seen for the (n,2n) reaction, which was about 20% larger than the experiments for incident energies ≤ 14 MeV.

36001280
Neutronics design of accelerator-driven system for power flattening and beam current reduction
Nishihara, Kenji; Iwanaga, Kohei*; Tsujimoto, Kazufumi; Kurata, Yuji; Oigawa, Hiroyuki; Iwasaki, Tomohiko*
Journal of Nuclear Science and Technology 45(8), p.812-822(2008) ; (JAEA-J 04575)

In the present neutronics design of the Accelerator-driven system (ADS) cooled by lead-bismuth eutectic (LBE), we investigated several methods to reduce the power peak and beam current, and estimated the temperature drops of the cladding tube and beam window. The methods are adjustment of inert matrix ratio in fuel in each burn-up cycle, multi-region design in terms of pin radius or inert matrix content, and modification of the level of the beam window position and the height of the central fuel assemblies. As the result, we optimized the ADS combined with the adjustment of inert matrix ratio in each burn-up cycle, multi-region design in terms of inert matrix content and deepened window level. The maximum temperatures of the optimized ADS at the surface of the cladding tube and the beam window were reduced by 91 and 38 °C, respectively.

36001281
Effect of pulse electrolysis on morphology of co-deposited MOX granules
Kofuji, Hirohide; Okamura, Nobuo; Mizuguchi, Koji*; Myochin, Munetaka
Journal of Nuclear Science and Technology 45(9), p.942-950(2008) ; (JAEA-J 04576)

In the oxide electrowinning method of nuclear fuel recycling, the applicability of the pulse electrolysis method to the MOX co-deposition process was evaluated. Several experiments were conducted involving uranium, plutonium, and elements simulating fission product (FP) or corrosion product (CP). Through study of the results of these experiments, the influences of the impurities and the effect of the waveform of electrolysis pulses on the electro-deposit were clarified. As a result, pulse electrolysis conditions which could restrain Pu enrichment of the deposited MOX were confirmed. Furthermore, it was found that the element distribution in the MOX granule obtained by the pulse electrolysis was homogenized, which is well suited for nuclear fuel fabrication. Finally, a qualitative model of the pulse electrolysis reaction near the field of cathode surface is proposed.

36001282
Installation places of criticality accident detectors in the plutonium conversion development facility
Sanada, Yukihisa; Tsujimura, Norio; Shimizu, Yoshio; Izaki, Kenji; Furuta, Sadaaki
Journal of Nuclear Science and Technology, Supplement 5 (June 2008) , p.74-77(2008) ; (JAEA-J 04577)

The purpose of this study is the establishment of the determination procedures for the placements of CAAS detectors in PCDF. The dose of detection point was evaluated the simple equation which was formulated in calculated factors by MCNP and ANISN. When the alarm trip point was 2.0 mGy/h, the detection area was covered 30 m distances from the equipment to the CAD and 100 cm concrete shielding. This result will be reflected in the determination of the CAD placements and three CADs were placed in PCDF.

36001283
Isotope separation by condensed matter centrifugation; Sedimentation of isotope atoms in Se
Mashimo, Tsutomu; Ono, Masao; Huang, X.*; Iguchi, Yusuke*; Okayasu, Satoru; Kobayashi, Katsura*; Nakamura, Eizo*
Journal of Nuclear Science and Technology, Supplement 5 (September 2008) , p.105-107(2008) ; (JAEA-J 04578)

It was observed that the concentration ratio ⁸²Se/⁷⁶Se increased by % level in the specimen ultracentrifuged at 0.7∼0.9 million G and at 300°C(liquid state) or 190°C (solid state), respectively. The present result is evidence of sedimentation of substitutional atoms in condensed matter via self-diffusion, and suggests its possible application to isotope separation by condensed matter centrifugation.

36001284
Isotope fluctuation in indium-lead alloy induced by solid centrifugation
Ono, Masao; Iguchi, Yusuke*; Okayasu, Satoru; Esaka, Fumitaka; Kobayashi, Katsura*; Hao, T.; Bagum, R.*; Osawa, Takahito; Fujii, Kimio; Nakamura, Eizo*; Mashimo, Tsutomu
Journal of Nuclear Science and Technology, Supplement 5 (September 2008) , p.108-110(2008) ; (JAEA-J 04579)

The atomic-scale graded structure of In-Pb alloy was formed by an ultracentrifuge experiment under conditions that a gravitational field of 810,000 G for 100 hours at 150°C (solid state) in our previous study. The isotope fluctuation on this sample was measured using secondary ion mass spectrometer (SIMS). The ratio both ²⁰⁸Pb/²⁰⁶Pb and ¹¹⁵In/¹¹³In changed with positive gradient in the direction of centrifugal force approximately 1.2%. These isotope fluctuations were larger than that of starting state of natural state (In<0.2%, Pb<0.1%). These show that the sedimentation of isotopes occurred by solid centrifugation in this alloy, although achieved concentration gradients were small.

36001285
Study on the intervention and return criteria for relocation using PSA method
Takahara, Shogo; Kimura, Masanori; Matsubara, Takeshi*; Homma, Toshimitsu
Journal of Nuclear Science and Technology, Supplement 5 (June 2008) , p.714-717(2008) ; (JAEA-J 04580)

It is recognized that good preparedness and arrangement in advance of an emergency can improve the emergency response to a nuclear and radiological emergency. In the preparedness, comprehensive threat assessment is very important to provide technical guidance for developing the protective actions. Probabilistic safety assessment method is useful for assessing accident consequences comprehensively and quantitatively. In this study, an accident consequence assessment code OSCAAR, which was developed at the Japan Atomic Energy Agency, is used to provide the information for the guideline of intervention and return criteria for relocation on the long-term emergency situation.

36001286
Pulse radiolysis study on free radical scavenger edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one)
Lin, M.; Katsumura, Yosuke; Hata, Kuniki; Muroya, Yusa*; Nakagawa, Keiichi*
Journal of Photochemistry and Photobiology B; Biology 89(1), p.36-43(2007) ; (JAEA-J 04581)

The reactions between edaravone and various one-electron oxidants such as OH, N₃, Br₂^-, and SO₄^- radical have been studied by pulse radiolysis techniques. The transient species produced by the reaction of edaravone with OH radical shows an absorption band with λ_max = 320 nm, while the oxidation by N₃, Br₂^-, SO₄^- and CCl₃OO results in an absorption band with λ_max = 345 nm. Different from the previous reports, the main transient species by the reaction of edaravone with OH radical in the absence of O₂ is attributed to OH-adducts. At neutral condition (pH 7), the rate constants of edaravone reacting with OH, N₃, SO₄^-, CCl₃OO, and e_ag^- are estimated to be 8.5×10⁹, 5.8×10⁹, 6×10⁸, 5.0×10⁸ and 2.4×10⁹ dm³ mol^-1s^-1, respectively. From the pH dependence on the formation of electron adducts and on the rate constant of edaravone with hydrated electron, the pKa of edaravone is estimated to be 6.9±0.1.

36001287
Isotopically selective infrared multiphoton dissociation of 2,3-dihydropyran
Yokoyama, Atsushi; Katsumata, Keiichi*; Oba, Hironori; Akagi, Hiroshi; Saeki, Morihisa; Yokoyama, Keiichi
Journal of Physical Chemistry A 112(29), p.6571-6577(2008) ; (JAEA-J 04582)

Oxygen isotope separation has been examined by using an infrared multiphoton dissociation of 2,3-dihydropyran. Enrichment factor has been measured by the CO₂ laser irradiation of the samples as a function of laser frequency, laser fluence, and sample pressure. Maximum enrichment factor of 751 has been obtained, and ¹⁸O, natural abundance of which is 0.205 %, was enriched to 60 %. Moreover, it was found that the enrichment factor increases with increasing the sample pressure, which was different from the infrared multiphoton dissociation of usual molecules. This phenomenon was discussed on the basis of a simulation by a rate equation model including a collisional vibrational relaxation.

36001288
Laser-driven proton acceleration from a near-critical density target
Yogo, Akifumi; Daido, Hiroyuki; Bulanov, S. V.; Esirkepov, T. Z.; Nemoto, Koshichi*; Oishi, Yuji*; Nayuki, Takuya*; Fujii, Takashi*; Ogura, Koichi; Orimo, Satoshi; Sagisaka, Akito; Ma, J.-L.; Mori, Michiaki; Nishiuchi, Mamiko; Pirozhkov, A. S.; Nakamura, Shu*; Noda, Akira*; Nagatomo, Hideo*
Journal of Physics; Conference Series 112, p.042034_1-042034_4(2008) ; (JAEA-J 04583)

In this work, we present a new method to enhance the proton generation by a 10⁵-contrast laser. High-energy protons up to 3.8 MeV are observed with 7.5-μm-thick insulator (Polyimide) target irradiated by a laser pulse having energy of 0.8 J and an intensity of 10¹⁹-W/cm². Using two time-of-flight (TOF) spectrometers simultaneously in different directions, we measure the direction dependency of proton-energy spectra. As a result, we find that high-energy component of proton beam is shifted away from the target normal toward the laser-propagation direction, when the laser is focused with 45° incident angle. The TOF measurements over 130 laser shots confirm that the generation of the high-energy protons, which are steered away from the target normal, depends strongly on the laser-focusing condition.

36001289
Preface; 11th IAEA Technical Meeting on H-mode Physics and Transport Barriers
Takizuka, Tomonori
Journal of Physics; Conference Series 123, p.011001_1(2008) ; (JAEA-J 04584)

36001290
Power requirement for accessing the H-mode in ITER
Martin, Y. R.*; Takizuka, Tomonori; ITPA CDBM H-mode Threshold Database Working Group*
Journal of Physics; Conference Series 123, p.012033_1-012033_11(2008) ; (JAEA-J 04585)

36001291
²⁷Al NMR evidence for the strong-coupling d-wave superconductivity in NpPd₅Al₂
Chudo, Hiroyuki; Sakai, Hironori; Tokunaga, Yo; Kambe, Shinsaku; Aoki, Dai*; Homma, Yoshiya*; Shiokawa, Yoshinobu*; Haga, Yoshinori; Ikeda, Shugo*; Matsuda, Tatsuma; Onuki, Yoshichika; Yasuoka, Hiroshi
Journal of the Physical Society of Japan 77(8), p.083702_1-083702_4(2008) ; (JAEA-J 04586)

We present ²⁷Al NMR studies for a single crystal of the newly developed superconductor NpPd₅Al₂ (T_c=4.9 K). In the superconducting state, the ²⁷Al NMR spectrum shifts to lower frequencies owing to a decrease of the spin part of the Knight shift, and exhibits broadening characteristic of the local field distribution associated with a vortex lattice. We have also found that the ²⁷Al nuclear spin-lattice relaxation rate (1/T₁) decreases just below T_c with no coherence peak and shows T³ behavior at low temperatures. The observed temperature dependences of the Knight shift and 1/T₁ in general accord with those assuming a line-node superconducting gap with the gap value of 2Δ/k_BT_c ∼ 6.4. Therefore, the present NMR data provides evidence for strong-coupling d-wave superconductivity in NpPd₅Al₂.

36001292
Qualitative detection of Mg content in a leaf of hedera helix by using X-ray radiation from a laser plasma source
Reale, L.*; Lai, A.*; Sighicelli, M.*; Faenov, A. Y.; Pikuz, T.*; Flora, F.*; Zuppella, P.*; Limongi, T.*; Palladino, L.*; Poma, A.*; Kaiser, J.*; Galiová, M.*; Balerna, A.*; Cinque, G.*
Microscopy Research and Technique 71(6), p.459-468(2008) ; (JAEA-J 04587)

A method to reveal the presence of Mg content inside the different parts of leaves of Hedera helix is analyzed under X-ray radiation, obtained from a plasma source with a Mg target. We found that the green side of the leaf is highlighted. We may suppose that the reason why the X-rays from a Mg plasma source, allow us to pick up the green side is probably duet the greater presence of the amount of Mg (from chlorophyll or other complexes and/or salts) in the two sides, green and white, of the leaf.

36001293
Bringing accelerators down to size
Tajima, Toshiki
Nature Photonics 2(9), p.526-527(2008) ; (JAEA-J 04588)

Recent experimental progress in laser acceleration now achieves stable repeatable electron bunches. This paves a way toward much compactified accelerator delivering brilliant electron and subsequent X-ray beams.

36001294
Comparisons of density profiles in JT-60U tokamak and LHD helical plasmas with low collisionality
Takenaga, Hidenobu; Tanaka, Kenji*; Muraoka, Katsunori*; Urano, Hajime; Oyama, Naoyuki; Kamada, Yutaka; Yokoyama, Masayuki*; Yamada, Hiroshi*; Tokuzawa, Tokihiko*; Yamada, Ichihiro*
Nuclear Fusion 48(7), p.075004_1-075004_11(2008) ; (JAEA-J 04589)

In order to understand particle transport systematically in toroidal plasmas, electron density profiles were compared in JT-60U tokamak and LHD helical plasmas with low collisionality. Peakedness of density profiles increased with decreasing collisionality in ELMy H-mode plasmas of JT-60U, when the collisionality at half the minor radius was in the collisionless regime. Collisionality dependence of density profiles in LHD plasmas was similar to that in JT-60U plasmas in the same collisionality regime, when neoclassical transport was suppressed by geometrical optimization. On the other hand, in the LHD plasmas having relatively larger neoclassical transport than that in the above case, peakedness of density profiles decreased with decreasing collisionality. Neoclassical transport enhanced by the non-axisymmetric effect significantly affected density profiles with low collisionality in LHD plasmas. Density profiles in LHD plasmas tended to approach those in JT-60U, which are dominated by anomalous transport, as the contribution of neoclassical transport was reduced.

36001295
Particle control in long-pulse H-mode discharges of JT-60U
Nakano, Tomohide; Kubo, Hirotaka; Asakura, Nobuyuki; Takenaga, Hidenobu; Oyama, Naoyuki; Kawashima, Hisato; Fujimoto, Kayoko
Nuclear Fusion 48(8), p.085002_1-085002_8(2008) ; (JAEA-J 04590)

Particle control is one of the key issues for steady-state operation in fusion reactors. In short discharges, the first wall absorbs hydrogen particles and it works as a pump (wall pumping). The wall pumping is effective to control the plasma density. However, in future tokamak devices, wall retention increases in a long discharge. Then, it is expected that the wall retention is saturated and the wall pumping does not work. Therefore, for steady-state operation, particle control by active divertor pumping without the wall pumping should be established. In JT-60U, long-pulse high-density H-mode plasmas have been sustained by divertor pumping under global wall saturation. The energy confinement and ELM activity can be sustained, while wall pumping does not work and even outgas appears. The outgas is attributed to increase in the divertor-plate temperature. On the other hand, wall pumping continues for longer than 20 s in high-density (ne ∼ 0.8 nGW) discharges with an X-point MARFE and detached divertor plasma. X-point MARFEs have also been controlled by the divertor pumping. As a result, the electron density control by the divertor pumping and the gas puffing is effective under the wall saturation. However, it should be noted that the wall-pumping rate changes to maintain the electron density against the control. The change in the wall pumping suggests dynamic equilibrium between particle flux and desorption as an important wall-pumping mechanism.

36001296
Measurement of thick target neutron yields at 0° bombarded with 140, 250 and 350 MeV protons
Iwamoto, Yosuke; Taniguchi, Shingo*; Nakao, Noriaki*; Itoga, Toshio*; Yashima, Hiroshi*; Nakamura, Takashi*; Sato, Daiki; Nakane, Yoshihiro; Nakashima, Hiroshi; Kirihara, Yoichi*; Hagiwara, Masayuki*; Iwase, Hiroshi*; Oishi, Koji*; Tamii, Atsushi*; Hatanaka, Kichiji*
Nuclear Instruments and Methods in Physics Research A 593(3), p.298-306(2008) ; (JAEA-J 04591)

Neutron energy spectra at 0° produced from stopping-length graphite, aluminum, iron and lead targets bombarded with 140, 250 and 350 MeV protons were measured at the neutron TOF course in RCNP of Osaka University. The neutron energy spectra were obtained by using the time-of-flight technique in the energy range from 10 MeV to incident proton energy. To compare the experimental results, Monte Carlo calculations with the PHITS and MCNPX codes were performed using the JENDL-HE and the LA150 evaluated nuclear data files, the ISOBAR model implemented in PHITS, and the LAHET code in MCNPX. It was found that these calculated results at 0° generally agreed with the experimental results in the energy range above 20 MeV except for graphite at 250 and 350 MeV.

36001297
Effects of composition and structure on hydrogen incorporation in tungsten oxide films deposited by sputtering
Inoue, Aichi; Yamamoto, Shunya; Nagata, Shinji*; Yoshikawa, Masahito; Shikama, Tatsuo*
Nuclear Instruments and Methods in Physics Research B 266(15), p.3381-3386(2008) ; (JAEA-J 04592)

The effects of composition and structure on hydrogen incorporation property in tungsten oxide films were investigated. The tungsten oxide was deposited on carbon and SiO₂ substrates to form films by varying the temperature from 30 to 600 °C using a reactive sputtering in argon and oxygen mixture. We obtained amorphous structure in the films deposited below 400 °C and (0 1 0) oriented monoclinic WO₃ in the films deposited beyond 400 °C. Hydrogen concentration in the films increased from 0.1 to 0.7 H/W with changing the composition from WO_0.25 to WO₃. The hydrogen concentration in WO₃ films decreased to 0.4 H/W with increasing the substrate temperature during deposition. The Raman spectra of the WO₃ films revealed that decreasing of W⁶⁺=O terminals was related to that of the hydrogen concentration. It was considered in detail that the incorporated hydrogen in tungsten oxide films was bonded at the end of W⁶⁺=O terminals.

36001298
Quantum synchronization effects in intrinsic Josephson junctions
Machida, Masahiko; Kano, Takuma*; Yamada, Susumu; Okumura, Masahiko; Imamura, Toshiyuki*; Koyama, Tomio*
Physica C 468(7-10), p.689-694(2008) ; (JAEA-J 04593)

36001299
Possible mechanism of charge stripe formation based on the ring exchange interaction
Sakai, Toru
Physica C 468(15-20), p.1163-1165(2008) ; (JAEA-J 04594)

The charge stripes observed in the high-Tc cuprate superconductors have attracted a great interest in the field of superconductivity for a long time. A lot of clear evidences were detected by the neutron scattering and the STM etc. In our previous works, we proposed a possible mechanism of the charge stripe formation based on the ring exchange interaction which is originated from the strong electron correlation. The numerical exact diagonalization study of the t-J model with the ring exchange gave a reasonable phase diagram of the vertical charge stripe in the work. However, some transition metal oxides did not exhibit only the vertical charge stripe but also the diagonal one. In the present study, we investigate two-types of charge stripes and present a new phase diagram including the both charge stripe phases.

36001300
MUTA calculations of a laser-produced Mg hollow atom spectrum
Colgan, J.*; Abdallah Jr., J.*; Faenov, A. Y.; Pikuz, T. A.*; Skobelev, I. Yu.*
Physica Scripta 78(1), p.015302_1-015302_6(2008) ; (JAEA-J 04595)

A study is made of the spectra produced from a short-wavelengths long-pulse (nanosecond) laser incident on an Mg plasma. A very complex experimental spectrum is analyzed in detail by comparison with large-scale atomic kinetics calculations using mixed-UTA (MUTA) model.

36001301
EPR identification of intrinsic defects in SiC
Isoya, Junichi*; Umeda, Takahide*; Mizuochi, Norikazu*; Son, N. T.*; Janzén, E.*; Oshima, Takeshi
Physica Status Solidi (B) 245(7), p.1298-1314(2008) ; (JAEA-J 04596)

Intrinsic defects in silicon carbide (SiC) were indentified using Electron Paramagnetic Resonance (EPR). The samples used in this study were cubic (3C) and hexagonal (4H, 6H) SiC. The angular dependence of hyperfine structure of ²⁹Si, ¹³C was compared to the results from the first principle calculations As the results, positively charged carbon vacancies in h and k sites (V_C⁺(h), V_C⁺(k)), negatively charged carbon vacancy (V_C^-(h)), and neutoral, positively and negatively charged di-vacancies of silicon vacancy and carbon vacancy ([V_SiV_C]⁰, [V_SiV_C]⁺, [V_SiV_C]^-) were identified.

36001302
Stripe formation in fermionic atoms on a two-dimensional optical lattice inside a box trap; Density-matrix renormalization-group studies for the repulsive Hubbard model with open boundary conditions
Machida, Masahiko; Okumura, Masahiko; Yamada, Susumu
Physical Review A 77(3), p.033619_1-033619_5(2008) ; (JAEA-J 04597)

We suggest that a box shape trap enables one to observe intrinsic properties of the repulsive Hubbard model in a fixed doping in contrast to the conventional harmonic trap bringing about spatial variations of atom density profiles. In order to predict atomic density profile under the box trap, we apply the directly extended density-matrix renormalization-group method to a four-leg repulsive Hubbard model with the open boundary condition. Consequently, we find that stripe formation is universal in a low-hole-doping range and the stripe sensitively changes its structure with variations of U/t and the doping rate. A remarkable change is that a stripe formed by a hole pair turns to one by a bihole pair when entering a limited strong U/t range. Furthermore, a systematic calculation reveals that the Hubbard model shows a change from the stripe to the Friedel like oscillation with increasing the doping rate.

36001303
Single-neutron knockout from intermediate energy beams of ^30,32Mg; Mapping the transition into the "island of inversion"
Terry, J. R.*; Brown, B. A.*; Campbell, C. M.*; Cook, J. M.*; Davies, A. D.*; Dinca, D.-C.*; Gade, A.*; Glasmacher, T.*; Hansen, P. G.*; Sherrill, B. M.*; Zwahlen, H.*; Bazin, D.*; Yoneda, Kenichiro*; Tostevin, J. A.*; Otsuka, Takaharu*; Utsuno, Yutaka; Pritychenko, B.*
Physical Review C 77(1), p.014316_1-014316_12(2008) ; (JAEA-J 04598)

36001304
Excited intruder states in ³²Mg
Tripathi, V.*; Tabor, S. L.*; Bender, P.*; Hoffman, C. R.*; Lee, S.*; Pepper, K.*; Perry, M.*; Mantica, P.*; Cook, J. M.*; Pereira, J.*; Pinter, J. S.*; Stoker, J.*; Weissharr, D.*; Utsuno, Yutaka; Otsuka, Takaharu*
Physical Review C 77(3), p.034310_1-034310_8(2008) ; (JAEA-J 04599)

Excited states in ³²Mg have been observed from a β-decay experiment of ³²Na which was performed at National Superconducting Cyclotron Laboratory in Michigan State University. The 2.1 MeV state proposed previously was denied because the corresponding γ ray is found to be located elsewhere. New level scheme is proposed and compared with the Monte Carlo shell model by JAEA. The ground state of ³²Na appears to be a negative parity states from the decay pattern and the calculation. We suggested that the configuration of the states which are strongly populated via the β decay is 3p-3h, since the ground state of the parent nucleus is most likely 2p-3h character.

36001305
¹³⁸La-¹³⁸Ce-¹³⁶Ce nuclear cosmochronometer of supernova neutrino process
Hayakawa, Takehito; Shizuma, Toshiyuki; Kajino, Toshitaka*; Ogawa, Kengo*; Nakada, Hitoshi*
Physical Review C 77(6), p.065802_1-065802_5(2008) ; (JAEA-J 04600)

36001306
Half-life of the ¹⁶⁴Ho by the (γ,n) reaction from Laser Compton scattering γ rays at the electron storage ring NewSUBARU
Hayakawa, Takehito; Shizuma, Toshiyuki; Miyamoto, Shuji*; Amano, So*; Horikawa, Ken*; Ishihara, Kazuki*; Mori, Michiaki; Kawase, Keigo; Kando, Masaki; Kikuzawa, Nobuhiro; Chiba, Satoshi; Mochizuki, Takayasu*; Kajino, Toshitaka*; Fujiwara, Mamoru
Physical Review C 77(6), p.068801_1-068801_4(2008) ; (JAEA-J 04601)

36001307
Absence of broken time-reversal symmetry in the pseudogap state of the high temperature La_2-xSr_xCuO₄ superconductor from muon-spin-relaxation measurements
MacDougall, G. J.*; Aczel, A. A.*; Carlo, J. P.*; Ito, Toshimitsu*; Rodriguez, J.*; Russo, P. L.*; Uemura, Yasutomo*; Wakimoto, Shuichi; Luke, G. M.*
Physical Review Letters 101(1), p.017001_1-017001_4(2008) ; (JAEA-J 04603)

We have performed zero-field muon spin rotation measurements on single crystals of La_2-xSr_xCuO₄ to search for spontaneous currents in the pseudo-gap state. By comparing measurements on materials across the phase diagram, we put strict upper limits on any possible time-reversal symmetry breaking fields that could be associated with the pseudo-gap. Comparison between experimental limits and proposed circulating current states effectively eliminates the possibility that such states exist in this family of materials.

36001308
Kramer-Pesch approximation for analyzing field-angle-resolved measurements made in unconventional superconductors; A Calculation of the zero-energy density of states
Nagai, Yuki*; Hayashi, Nobuhiko
Physical Review Letters 101(9), p.097001_1-097001_4(2008) ; (JAEA-J 04604)

By measuring angular-oscillation behavior of the heat capacity with respect to the applied field direction, one can detect the details of the gap structure. We introduce the Kramer-Pesch approximation (KPA) as a new method to analyze the field-angle-dependent experiments quantitatively. We calculate the zero energy density of states for various combinations of typical Fermi surfaces and superconducting gaps. The KPA yields a merit that one can quantitatively compare theoretical calculations with experimental results without involving heavy numerical computations, even for complicated Fermi surfaces. We show an inadequacy of the frequently-used Doppler-shift technique, which is remedied by application of the KPA.

36001309
Quadrupole moment of ³⁷K
Minamisono, Kei*; Mantica, P. F.*; Crawford, H. L.*; Pinter, J. S.*; Stoker, J. B.*; Utsuno, Yutaka; Weerasiri, R. R.*
Physics Letters B 662(5), p.389-395(2008) ; (JAEA-J 04605)

36001310
Controlled electron injection into the wake wave using plasma density inhomogeneity
Brantov, A. V.*; Esirkepov, T. Z.; Kando, Masaki; Kotaki, Hideyuki; Bychenkov, V. Yu.*; Bulanov, S. V.
Physics of Plasmas 15(7), p.073111_1-073111_10(2008) ; (JAEA-J 04606)

The controlled electron injection for the laser wake field accelerator is studied on a basis of analytical estimates and two- and three-dimensional particle-in-cell simulations. The injection scheme requires a concordance of the density scale length and laser intensity. It is shown that for a moderate laser intensity electron injection into the wake wave using an optimal plasma density gradient provides electron beam with extremely low divergence, small energy spread and high energy.

36001311
Picosecond pulse radiolysis; Dynamics of solvated electrons in ionic liquid and geminate ion recombination in liquid alkanes
Yang, J.*; Kondo, Takafumi*; Norizawa, Kimihiro*; Nagaishi, Ryuji; Taguchi, Mitsumasa; Takahashi, Kenji*; Kato, Ryuji*; Anishchik, S. V.*; Yoshida, Yoichi*; Tagawa, Seiichi*
Radiation Physics and Chemistry 77(10-12), p.1233-1238(2008) ; (JAEA-J 04607)

First observation of picosecond dynamics in ionic liquid of DEMMA-TFSI in radiation chemistry was reported. It is found that the electron produced by ionization is solvated to full solvation in ionic liquid with a rate constant of 3.9×10¹⁰ s^-1. The yield of solvated electrons in picosecond time region is 1.2×10^-7 mol J^-1. The dry electron in ionic liquid reacts rapidly with biphenyl and pyrene with a rate constant of 3.8 to 7.9×10¹¹ L mol^-1 s^-1. The geminate ion recombination in n-dodecane and n-hexane was also observed by monitoring the transient absorptions at 523 nm.

36001312
Molar absorption coefficient and radiolytic yield of solvated electrons in diethylmethyl(2-methoxy)ammonium bis (trifluoromethanesulfonyl)imide ionic liquid
Asano, Akira*; Yang, J.*; Kondo, Takafumi*; Norizawa, Kimihiro*; Nagaishi, Ryuji; Takahashi, Kenji*; Yoshida, Yoichi*
Radiation Physics and Chemistry 77(10-12), p.1244-1247(2008) ; (JAEA-J 04608)

The molar extinction coefficient and the radiolytic yield of solvated electrons in ionic liquid of DEMMA-TFSI were estimated respectively to be 2.3×10⁴ L mol^-1 cm^-1 and 0.8×10^-7 mol J^-1 by observing the reaction and kinetics of solvated electron and dry electron in the ionic liquid. The solvated electron in DEMMA-TFSI has a very broad absorption spectrum peaking at 1100 nm and reacts slowly with pyrene with a rate constant of 3.5×10⁸ L mol^-1 s^-1, while the dry electron is captured rapidly by pyrene with C₃₇ value of 0.065 mol L^-1.

36001313
Evaluation of self-dose S values for positron emitters in voxel phantoms
Kinase, Sakae; Saito, Kimiaki
Radiation Protection Dosimetry 127(1-4), p.197-200(2007) ; (JAEA-J 04609)

In the present study, Monte Carlo simulations have been carried out to evaluate S values - the mean absorbed dose to the target region per unit cumulated activity in the source region - for positron emitters in the brain, the heart and the urinary bladder contents. The positron emitters of interest were four radionuclides that were used for PET imaging: ¹¹C, ¹³N, ¹⁵O and ¹⁸F. The S values were evaluated on the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine Pamphlet No.5 type phantom (MIRD 5 type phantom) and the adult voxel phantoms developed at the Japan Atomic Energy Research Institute (JAERI). Consequently, Monte Carlo simulation and voxel phantoms were found to be useful in the evaluation of the beta dose to organs, in particular to hollow organs such as the urinary bladder. It was also demonstrated that the self-dose S values largely depend on the beta-ray energy and the mass of each target region.

36001314
Development of a voxel phantom of Japanese adult male in upright posture
Sato, Kaoru; Noguchi, Hiroshi; Endo, Akira; Emoto, Yutaka*; Koga, Sukehiko*; Saito, Kimiaki
Radiation Protection Dosimetry 127(1-4), p.205-208(2007) ; (JAEA-J 04610)

Calculation of specific absorbed fractions (SAFs) used in internal dosimetry requires a human phantom. However, radiation exposure occurs under various postures, which may affect the shape and location of organs. Therefore, it is important to clarify the effect of posture on SAFs. In the present study, a voxel phantom was developed on the basis of CT images in upright posture, and the difference of SAFs between supine and upright postures was investigated. The authors developed the voxel phantom of Japanese adult in supine posture named JM for the evaluation of SAFs of Japanese adult male. The subject, who was employed for the construction of JM, was selected as a volunteer again to obtain the CT images. The developed voxel phantom in upright posture was named JM2. The voxel size of JM2 is 0.98mm×0.98mm×1mm, which is the same as that of JM. The fine voxels reproduce the shape and location of organs in the body realistically. It is possible to compare directly the change in the shape and location of organs due to the postures between JM and JM2, since the CT images for construction of the both phantoms were obtained from the identical person. This paper describes the physical characteristics of JM and JM2 and discusses the impact of posture on SAFs for photons in selected organs.

36001315
Ratio of aerosol and gases of radioactive chlorine and particle size distribution of aerosol formed by high-energy proton irradiation
Yokoyama, Sumi; Sato, Kaoru; Manabe, Kentaro; Noguchi, Hiroshi; Kaneko, Hirohisa; Oki, Yuichi*; Iida, Takao*; Tanaka, Susumu*
Radiation Protection Dosimetry 127(1-4), p.392-397(2007) ; (JAEA-J 04611)

To estimate internal doses due to the inhalation of radionuclides produced by the nuclear spallation of the air nuclei in high-energy proton accelerator facilities, the physicochemical properties of radionuclides are very important. However, there is not enough information of the properties for airborne radioactive chlorine formed from argon gas in the air of a high-energy proton irradiation field. Thus we have measured the ratio of aerosol and gases of radioactive chlorine which are formed by irradiating argon gas-added air with a 48 MeV proton beam. In addition, the particle size distribution and chemical form of non-radioactive aerosol were examined. It was found that Cl-38 and Cl-39 exist as aerosol, acidic and non-acidic gases. The percentages of Cl-38 and Cl-39 aerosols are more than 70%. In total radioactive chlorine gas, about 30% and 70% are acidic and non-acidic gases, respectively. The concentration of non-radioactive aerosol had a peak at an aerodynamic diameter of 20-30 nm in the early irradiation period. The particle size of non-radioactive aerosol shifted to larger with time. After 10 min, the aerosols grew very slowly and many of the non-radioactive aerosols were distributed widely under 200 nm. This suggests that the diameter of the radioactive chlorine aerosol formed by the attachment of the radioactive chlorine to the non-radioactive aerosol around a beam line of the accelerator is much smaller than the default value adopted in ICRP Publication 66.

36001316
Practical action levels for chelation therapy in plutonium inhalation using nose swab
Kurihara, Osamu; Takada, Chie; Takasaki, Koji; Ito, Kimio; Momose, Takumaro; Miyabe, Kenjiro
Radiation Protection Dosimetry 127(1-4), p.411-414(2007) ; (JAEA-J 04612)

Practical action levels for beginning chelation therapy to remove plutonium in the body are now under discussion in Japan since there has been no experience in administrating agents to a subject in accidental intake in Japan although a first commercial reprocessing plant is about to start operation. Recently, International Commission on Radiological Protection (ICRP) proposed some medical intervention levels for chelation therapy on ICRP Publication 96. These levels are determined based on internal dose however common monitoring methods such as lung counting or excreta analysis are not necessarily suitable in terms of both sensitivity and promptness. As an alternative, the authors paid attention to nose swabs and introduced the practical action levels.

36001317
Development of PARMA; PHITS-based Analytical Radiation Model in the Atmosphere
Sato, Tatsuhiko; Yasuda, Hiroshi*; Niita, Koji*; Endo, Akira; Sihver, L.*
Radiation Research 170(2), p.244-259(2008) ; (JAEA-J 04613)

Estimation of cosmic-ray spectra in the atmosphere has been an essential issue for the evaluation of aviation doses. We have therefore calculated these spectra by performing Monte Carlo simulation of cosmic-ray propagation in the atmosphere using the PHITS code. Based on a comprehensive analysis of the simulation results, we proposed an analytical model for estimating the cosmic-ray spectra of neutrons, protons, He nuclei, muons, electrons, positrons and photons applicable to any location in the atmosphere at altitudes below 20 km. Our model, named PARMA, enables us to calculate the cosmic radiation doses instantaneously with precision equivalent to that of the Monte Carlo simulation that requires much computational time. With these properties, PARMA is capable of improving the accuracy and efficiency of the cosmic-ray exposure dose estimations for not only aircrews but also for the public on the ground.

36001318
Uniform H^- ion beam extraction in a large negative ion source with a tent-shaped magnetic filter
Tobari, Hiroyuki; Hanada, Masaya; Kashiwagi, Mieko; Taniguchi, Masaki; Umeda, Naotaka; Watanabe, Kazuhiro; Inoue, Takashi; Sakamoto, Keishi; Takado, Naoyuki*
Review of Scientific Instruments 79(2), p.02C111_1-02C111_4(2008) ; (JAEA-J 04614)

In order to improve the spatial uniformity of negative ion beam, a novel magnetic filter, the tent-shaped filter was applied in the JAEA 10 ampere negative ion source as a replacement to the conventional external magnetic filter. The cusp magnetic field configuration for plasma confinement was changed to form a symmetric cusp field commonly used in many of positive ion sources for high proton yield. This configuration together with the tent filter allows fast electrons emitted from filaments drift azimuthally around the beam axis. This is a major advantage of the current configuration to prevent localization of fast electrons due to B × grad B drift in the external filter field. As the result, the standard deviation of H^- ion beam profile extracted from a wide area of 170 mm × 340 mm decreased from 16% with the external filter to 7.9 % with the tent filter. Thus the ion source with the tent filter demonstrated the uniform beam extraction that fulfilled the requirement for ITER NBI.

36001319
Effect of Pb-Pb correlation in diffuse scattering of powder PbF₂
Xianglian*; Basar, K.*; Honda, Hiroyuki*; Siagian, S.*; Ohara, Kota*; Sakuma, Takashi*; Takahashi, Haruyuki*; Igawa, Naoki; Ishii, Yoshinobu*
Solid State Ionics 179(21-26), p.776-779(2008) ; (JAEA-J 04615)

Diffuse X-ray and neutron scattering from powder PbF₂ are measured at 15 and 294K. Those oscillatory profile of diffuse scattering is explained by including the correlation effects among thermal displacements of atoms. The contribution of correlated thermal vibration of Pb-Pb atoms located at far-off distance to the oscillatory profile of diffuse scattering intensities is first confirmed.

36001320
Water transport properties of crosslinked-PTFE based electrolyte membranes
Sawada, Shinichi; Yamaki, Tetsuya; Nishimura, Hidetoshi*; Asano, Masaharu; Suzuki, Akihiro*; Terai, Takayuki*; Maekawa, Yasunari
Solid State Ionics 179(27-32), p.1611-1614(2008) ; (JAEA-J 04616)

We measured the self-diffusion coefficient of water, D, in proton exchange membranes (PEMs) based on crosslinked polytetrafluoroethylene (PTFE) films by a radiotracer-permeation method using tritium labeled water (HTO). When the crosslinking density of the PTFE matrix increased, the D value became smaller. This decreasing trend coincided with that of a water-content parameter, λ, defined as the number of water molecules per sulfonic acid (SO₃H) group. According to the model assumption of hydrophilic regions, the relationship between the D and λ indicates that the amount of free water in the crosslinked-PTFE PEMs could be lower than that in the non-crosslinked one, thereby restricting the mobility of water molecules through strong interactions between the majority of water and SO₃H groups.

36001321
Application of direct-fitting, mass integral, and multirate methods to analysis of flowing fluid electric conductivity logs from Horonobe, Japan
Doughty, C.*; Tsang, C.-F.*; Hatanaka, Koichiro; Yabuuchi, Satoshi; Kurikami, Hiroshi
Water Resources Research 44(8), p.W08403_1-W08403_11(2008) ; (JAEA-J 04617)

The flowing fluid electric conductivity (FFEC) logging method is an efficient way to provide information on the depths, salinities, and inflow strengths of individual conductive features intercepted by a borehole, without the use of specialized probes. The present paper presents the application of the method to two zones within a 1000-m borehole in sedimentary rock, which produced, for each zone, three sets of logs at different pumping rates, each set measured over a period of about one day.

36001322
Inception of anticline growth near the Omagari Fault, northern Hokkaido, Japan (in Japanese)
Ishii, Eiichi; Yasue, Kenichi; Ohira, Hiroto*; Furusawa, Akira*; Hasegawa, Takeshi*; Nakagawa, Mitsuhiro*
Chishitsugaku Zasshi 114(6), p.286-299(2008) ; (JAEA-J 04618)

36001323
Use of safety case concept in IAEA safety requirements document for geological disposal of radioactive waste (in Japanese)
Umeki, Hiroyuki
Genankyo Dayori (225), p.3-7(2008) ; (JAEA-J 04619)

36001324
Development of fast breeder reactor technology in Japan; Exploring substainable energy source for the next millennium (in Japanese)
Suzuki, Soju
Gijutsushi 20(9), p.16-19(2008) ; (JAEA-J 04620)

In view of the long-term energy security, the global warming prevention, the recent rapid rise of oil price etc., the time of Nuclear Power Renaissance has just come worldwide and the FBR is spotlighted again as a perspective technology leading the Renaissance. The Japan's approach to the commercialization of FBR is described briefly in this paper.

36001325
Construction of a voxel phantom based on CT data for a Japanese female adult and its use for calculation of organ doses from external electrons
Saito, Kimiaki; Koga, Sukehiko*; Ida, Yoshihiro*; Kamei, Tetsuya*; Funabiki, Jun*
Hoken Butsuri 43(2), p.122-130(2008) ; (JAEA-J 04621)

A voxel phantom for a Japanese female adult was developed according to CT data. The developed phantom Onago has a slightly larger size than the Asian Reference Man, Female (ARMF). The organ doses and effective doses for external electrons were calculated with the developed phantom in the energy range of 1 MeV through 10 GeV, and compared with those for a Japanese male voxel phantom Otoko and with those for a MIRD phantom. The organ doses show some typical tendencies which are common for all phantoms, but in some cases the absolute values of organ doses differ largely according to phantom. The maximum difference observed between the voxel phantoms and the MIRD-type phantom was a factor of fifty for the individual organ dose and a factor of two for the effective dose. This suggests the necessity of sophisticated phantoms and detailed investigation using the phantoms to find out the realistic reference organ doses and the fluctuations for external electron exposures.

36001326
Observation of energetic radiation associated with winter thunderstorm activity (in Japanese)
Torii, Tatsuo; Sugita, Takeshi*; Muraki, Yasushi*
Hoshasen 34(1), p.47-51(2008) ; (JAEA-J 04622)

γ-ray dose-rate increase associated with thunderstorm activities was observed on the ground in winter. To investigate the fluctuation profile during winter thunderstorms, the energetic radiation was measured by using four set of radiation detectors (LPRCs) which consist of four long proportional counters (2.5 m in length; 10 cm in diameter). These LPRC have a different response characteristic for the incident particle by mounting shield covers. It was also compared with the result measured at the same time by the environmental radiation monitors adopting an NaI scintillator / ionization chamber as a detector. Moreover, the electric field was measured at the same site by using a field mill. In the observation from December, 2006 to February, 2007, the count-rate fluctuation which seem to originate from thunderstorm activity observed by the LPRCs.

36001327
Fabrication of Si(110)-16×2 single-domain surface (in Japanese)
Yamada, Yoichi; Girard, A.*; Asaoka, Hidehito; Yamamoto, Hiroyuki; Shamoto, Shinichi
Hyomen Kagaku 29(7), p.401-406(2008) ; (JAEA-J 04623)

Widely well-defined Si(110)-16×2 single-domain surface has been fabricated utilizing the electromigration of the surface atoms. Tuning the direction of the dc during resistive heating to that of the surface reconstruction row realizes an alignment of the rows in one direction producing a mm-wide single-domain of 16×2 structure. The fabricated single-domain shows number of useful characteristics such as a strong one-dimensionality and the surface homochirality, suggesting various applications.

36001328
Formation of C_nH_x (n≥2) molecules from adsorbed methane by low-energy ion irradiation (in Japanese)
Narita, Ayumi; Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Honda, Mitsunori; Hirao, Norie; Yaita, Tsuyoshi
Hyomen Kagaku 29(8), p.489-494(2008) ; (JAEA-J 04624)

The formation of molecular ions and neutral molecules from adsorbed CH₄, CD₄ and N₂ following 1 keV He⁺ ion irradiation has been investigated. The thickness of the adsorbed layer was precisely controlled. For mono-layered methane, only monomer ions (CH_x⁺) were desorbed, while a large number of heavy ions (C_nH_x⁺) up to n = 20 as well as heavy neutral molecules (C_nH_x) were desorbed from multi-layered film. Among the desorbed ions and neutral molecules, molecules with C-C covalent bonds such as acetylene and ethylene were found. The results indicate that chemical bonds are newly formed by ion irradiation. Based on the results for thickness dependences of the mass spectra and calculation of He⁺ energy loss process from TRIM-Code, it was elucidated that the monomer ions are desorbed from the top surface layer through single electron excitation. On the other hand, the cluster ions are formed mainly in the inside of the layers along the nuclear track due to phonon excitation, which is produced by nuclear collision between incident He⁺ ions and adsorbed molecules.

36001329
Design concept of a knowledge management system of geological disposal technology (in Japanese)
Osawa, Hideaki; Umeki, Hiroyuki; Makino, Hitoshi; Takase, Hiroyasu*; McKinley, I. G.*; Okubo, Hiroo*
Karyoku Genshiryoku Hatsuden 59(6), p.26-33(2008) ; (JAEA-J 04625)

The information explosion resulting from modern technology is identified as a critical problem for deep geological disposal of high-level radioactive waste (HLW). A paradigm shift is needed in the basic concept for information management. This recognition had led to the development of a next generation Knowledge Management System (the JAEA KMS) that makes maximum use of recent developments in Information Technology (IT) and the methodology of Knowledge Engineering (KE) as applied in other technical fields. This paper provides a brief outline of the design concept of the JAEA KMS and then overviews recent progress towards development of an operational system.

36001330
Frontier of high pressure research on metal hydrides (in Japanese)
Aoki, Katsutoshi; Machida, Akihiko; Omura, Ayako*; Watanuki, Tetsu
Koatsuryoku No Kagaku To Gijutsu 18(3), p.273-278(2008) ; (JAEA-J 04626)

The highly compressed state of metal hydride has been investigated to explore structural and electronic transitions characteristic to hydride. The hydrogen atoms play the lead in the transitions, showing displacement in or transfer between the interstitial sites of a metal lattice. One example is the band gap closing observed for a long period lattice of yttrium tri-hydride, appearing at pressures above 12 GPa. Another example is photochromic event observed again for yttrium hydride. The former is likely accompanied by the in-site displacement of hydrogen atoms and the latter by the site-to-site transfer.

36001331
Toward commercialization of FBR cycle, 1 (in Japanese)
Nagaoki, Yoshihiro; Nagura, Fuminori; Sakaguchi, Tomoyoshi; Kawasaki, Hirotsugu; Kikuchi, Shin
Nippon Genshiryoku Gakkai-Shi 50(9), p.551-556(2008) ; (JAEA-J 04628)

"Fast Reactor Cycle Technology Development (FaCT)" project has been conducted since 2006. In this project, design study and research and development (R&D) on innovative technologies for fast reactor (FR) cycle system are implemented in order to present the conceptual designs of commercial and demonstration facilities by 2015 and start operating demonstration fast reactor in 2025. The R&Ds has been stepped forward into the development stage to establish the realization of innovative technologies which bring excellent performance to fast reactor cycle system. The purpose of R&D by 2010 is to decide weather innovative technologies shall be adopted. So promoting R&D of FR, the project governance was organized. Furthermore, several possible R&D have been effectively carried out within the frameworks of international cooperation, such as GNEP, GIF, and INPRO.

36001332
What is really happening in the wall? (in Japanese)
Murata, Isao*; Konno, Chikara
Nippon Genshiryoku Gakkai-Shi 50(9), p.574-579(2008) ; (JAEA-J 04629)

Charged particles confined in the plasma hurtle to the first wall in fusion reactors. They lose their energy immediately and do not enter the first wall so deeply. On the other hand, many neutrons are produced in the plasma by the fusion reaction. Because neutrons has no charge, they are prone to penetrate the wall. Their energy is high (about 14 MeV) and they can come up to the deeper position of the wall. They arrive to the blanket region rear of the first wall and cause various interactions (nuclear reactions). Here we will explain what is really happening there with neutron reactions and numerical simulation.

36001333
Anatomy and physiology of the alimentary tract system (in Japanese)
Sato, Kaoru
Nippon Hoken Butsuri Gakkai Senmon Kenkyukai Hokokusho Shirizu (Internet) 6(2), p.6-13(2008) ; (JAEA-J 04630)

36001334
Description of human alimentary tract model for radiological protection (in Japanese)
Kimura, Masanori; Hato, Shinji
Nippon Hoken Butsuri Gakkai Senmon Kenkyukai Hokokusho Shirizu (Internet) 6(2), p.36-42(2008) ; (JAEA-J 04631)

36001335
Concept design of cognitive methodology based data analysis system; Application to seismic analysis using finite element method (in Japanese)
Kino, Chiaki; Suzuki, Yoshio; Nishida, Akemi; Kushida, Noriyuki; Hayashi, Sachiko; Nakajima, Norihiro
Nippon Keisan Kogakkai Rombunshu (Internet) 2008(18), 8p.(2008) ; (JAEA-J 04632)

We have conducted research and development of the Cognitive methodology based Data Analysis System (CDAS) which supports researchers to analyze large scale data efficiently and comprehensively. Traditionally, much of data analysis process has been carried out by humans. However, when the scale of data is extremely large, data analysis is beyond the recognition capability of humans. The basic idea of CDAS is that computers execute data analysis instead of humans. In the present study, we showed three necessary functions (Verification and Validation: VV, Data Diagnosis: DD and Synthesis) for the design of CDAS. VV and DD functions are executed on gird computing environment and findings output from these functions are integrated on Synthesis functions. Finally CDAS displayed only useful information to human. We have applied the system to the virtual plant vibration simulator and succeeded in analyzing large scale data reaching to 1TB thoroughly for the first time.

36001336
Instrumental design of indirect geometry crystal analyzer spectrometerG DNA at J-PARC (in Japanese)
Shibata, Kaoru; Takahashi, Nobuaki; Nakagawa, Hiroshi; Fujiwara, Satoru; Kataoka, Mikio; Sato, Taku*; Kawakita, Yukinobu*; Tsukushi, Itaru*
Nippon Kessho Gakkai-Shi 50(1), p.46-50(2008) ; (JAEA-J 04633)

The instrumental design of an indirect geometry crystal analyzer spectrometer: DNA which is scheduled to be constructed in the Material and Life Science experimental Facility (MLF) at J-PARC, is reported in this article. This spectrometer is mainly aimed at searching for the high quality inelastic scattering spectra with only several mg order biomolecular sample in the plenty of wide range of energy and momentum transfers.

36001337
Multiscale modeling of three dimensional discrete dislocation dynamics and boundary element method and its application to nanoindentation problem (in Japanese)
Tsuru, Tomohito; Shibutani, Yoji*
Nippon Kikai Gakkai Rombunshu, A 74(743), p.933-938(2008) ; (JAEA-J 04634)

In the nano-plastic deformation, material properties cannot be described by the average rate of dislocation behavior, and it becomes increasingly necessary to trace individual motion of dislocations. Molecular dynamics (MD) is one of the most effective methodologies to obtain dislocation motion. However, MD simulation depends on the computer power so strongly that it is difficult to treat mesoscopic behavior including collective dislocation motion. Discrete dislocation mechanics (DD) has a unique ability to treat dislocation motion. In the present paper, we construct a combined approach including both DD and the boundary element method, and succeed in representing the stress field of dislocation in the vicinity of traction free surface. Finally, we apply this model to the nanoindentation problem and found the relationship between displacement burst and collective dislocation motion.

36001338
Examination of appropriate formulations for velocity and pressure calculation methods at interfacial region on collocated physical variables' distribution (in Japanese)
Ito, Kei; Kunugi, Tomoaki*
Nippon Kikai Gakkai Rombunshu, B 74(743), p.1512-1521(2008) ; (JAEA-J 04635)

Authors are developing a high-precision simulation method for gas-liquid two-phase flows on an unstructured grid as a part of numerical studies on gas entrainment phenomena in a sodium-cooled fast reactor. In this study, unphysical behaviors of velocity or pressure distributions near gas-liquid interface are discussed and appropriate formulations are derived. By using these new algorithms, the unphysical behaviors disappeared and numerical simulations could be conducted stably. As a validation of developed simulation method, one air bubble rising in static water was simulated. As a result, simulated bubble shapes well coincided with experimentally observed shapes in each condition. In addition, similar bubble shapes and velocity distributions with results of simulations on the structured grid were obtained on the unstructured grid. These results show that our simulation method can achieve high-precision two-phase flow simulations on both the structured and the unstructured grids.

36001339
Front lines of structural analyses by pulsed neutron diffraction (in Japanese)
Shamoto, Shinichi; Suzuya, Kentaro; Kamiyama, Takashi*; Kodama, Katsuaki; Otomo, Toshiya*; Fukunaga, Toshiharu*
Purazuma, Kaku Yugo Gakkai-Shi 84(6), p.323-332(2008) ; (JAEA-J 04638)

Pulsed neutron powder diffraction methods are reviewed, including the prospects at MLF facility in J-PARC center by top level scientists in Japan.

36001340
Generation of highly coherent soft-X-ray laser beam for application researches (in Japanese)
Nishikino, Masaharu
Purazuma, Kaku Yugo Gakkai-Shi 84(7), p.431-435(2008) ; (JAEA-J 04639)

36001341
Emission measurement of solid-state material excited with a soft-X-ray laser (in Japanese)
Tanaka, Momoko; Furukawa, Yusuke*; Sarukura, Nobuhiko*
Purazuma, Kaku Yugo Gakkai-Shi 84(7), p.443-445(2008) ; (JAEA-J 04640)

X-ray laser is a characteristic EUV source with short pulse duration of several pico-seconds, narrow spectral width, and high coherence. As an application of the X-ray laser, the UV emission from the ZnO single crystal excited by the 13.9 nm X-ray laser was observed and evaluated for EUV scintillator. The response time is sufficiently short for characterizing EUV lithography light sources having several nanoseconds duration. It is also shown that the X-ray laser is an excellent tool for time-resolved spectroscopy and characterization of materials intended for next-generation lithography applications.

36001342
Future prospect of plasma soft X-ray lasers (in Japanese)
Kawachi, Tetsuya
Purazuma, Kaku Yugo Gakkai-Shi 84(7), p.450-453(2008) ; (JAEA-J 04641)

Electron impact excitation X-ray laser, which required firstly huge driver laser facility dedicated to the inertial confinement fusion science, becomes smaller and smaller in the last 20 years, and now we can obtain brilliant coherent soft X-ray pulses with table-top high repetition Ti:Sapphire laser system. However, in order to apply these novel light sources to various research fields, we have to overcome several difficulties, such as the improvement of energy conversion efficiency, extension to the shorter wavelength region including water-window region, and technology to handle with the coherent soft X-ray light. In this paper, the author shows the research activity on X-ray lasers in the last 20 years, and discuss the future prospect of table top laser-driven plasma X-ray lasers.

36001343
Photo-medical valley; "Photo Medical Research Center" (in Japanese)
Kawanishi, Shunichi; Daido, Hiroyuki; Tajima, Toshiki
Reza Kenkyu 36(7), p.440-446(2008) ; (JAEA-J 04645)

36001344
Advanced research on hydrogen storage materials using synchrotron radiation light sources (in Japanese)
Machida, Akihiko; Aoki, Katsutoshi
Suiso Enerugi Shisutemu 32(4), p.14-19(2007) ; (JAEA-J 04646)

Science and technology concerning hydrogen storage materials are advancing towards the nanometer scale. X-rays, which have wave lengths matched to this length scale, are an ideal tool to study materials in nanometer scale. SPring-8, the world-biggest synchrotron radiation facility, provides ultra-brilliant, high-directional, polarized and pulsed X-rays. These excellent lights enable us to investigate precisely, accurately and even time dependently the structural and electronic properties of materials on hydrogenation and/or dehydrogenation. We present the synchrotron radiation based X-rays experiments that are powerful and useful particularly for the functional study of hydrogen storage materials. The latest results on metal hydrides are presented as example.

36001345
Development of conduits for the ITER central solenoid conductor (in Japanese)
Hamada, Kazuya; Nakajima, Hideo; Kawano, Katsumi; Takano, Katsutoshi; Tsutsumi, Fumiaki; Okuno, Kiyoshi; Fujitsuna, Nobuyuki*; Teshima, Osamu*
Teion Kogaku 43(6), p.244-251(2008) ; (JAEA-J 04647)

Japan Atomic Energy Agency has developed JK2LB conduit for the Nb₃Sn conductor of the ITER Central Solenoid. Mechanical requirements for the CS conductor conduit are 0.2% yield strength of more than 900 MPa and fracture toughness K _IC(J) of more than 130 MPa√m after a compaction and aging heat treatment (650 °C, 240 hours). In the previous work, aged JK2LB conduit has shown high strength and fracture toughness enough to satisfy the requirements. As a next step, work was performed to determine specification of the JK2LB conduit taking account of cold work including compaction and winding, and to simplify its fabrication process. To simulate the cold work effect and aging, mechanical tests were performed at 4.2 K on laboratory scale (20-30kg) ingot samples. It was found that the sum of carbon and nitrogen content should be in a range from 0.11% to 0.18% to achieve the ITER mechanical requirements. To obtain a grain size of conduit as well as that of small ingot sample, applicable solution heat treatment temperature and holding time were studied. In order to simplify the billet production process, we confirmed internal metallurgical qualities of JK2LB cast ingot. Since significant segregation was not observed, we could exclude an electroslag remelting process. Based on above achievements, full size JK2LB conduits were fabricated and satisfied the ITER mechanical requirements.

36001346
Kinetic simulations of turbulent fusion plasmas
Idomura, Yasuhiro; Watanabe, Tomohiko*; Sugama, Hideo*
AIP Conference Proceedings 1013 , p.270-286(2008) ; (JAEA-J 04648)

36001347
Radiotherapy using a laser proton accelerator
Murakami, Masao*; Hishikawa, Yoshio*; Miyajima, Satoshi*; Okazaki, Yoshiko; Sutherland, K.*; Abe, Mitsuyuki*; Bulanov, S. V.; Daido, Hiroyuki; Esirkepov, T. Z.; Koga, J. K.; Yamagiwa, Mitsuru; Tajima, Toshiki
AIP Conference Proceedings 1024 , p.275-300(2008) ; (JAEA-J 04649)

36001348
Formation of multi-layer structures in Bi₃Pb₇ intermetallic compounds under an ultra-high gravitational field
Mashimo, Tsutomu; Iguchi, Yusuke*; Bagum, R.*; Sano, Tomokazu*; Sakata, Osami*; Ono, Masao; Okayasu, Satoru
AIP Conference Proceedings 973 , p.502-505(2008) ; (JAEA-J 04650)

Ultra-high gravitational field (Mega-gravity field) can realize the sedimentation of atoms (diffusion) even in solids, and is expected to form a composition-graded structure and/or nonequilibrium phase in multi-component condensed matter. We had realized the sedimentation of substitutional solute atoms in miscible systems (Bi-Sb, In-Pb, etc.). In this study, the mega-gravity experiment at high temperature was performed on a thin-plate sample (0.7 mm in thickness) of intermetallic compound Bi₃Pb₇. A visible four-layers structure appeared, which indicated different microscopic structures. In the lowest-gravity region layer, Bi phase appeared. In the mid layers, the composition-graded structure was formed, while the powder X-ray diffraction patterns show difference. Such multi-layers structure was expected to show unique physical properties such as superconductivity. Keywords: Sedimentation of atoms, Ultra-high gravity field, Bi₃Pb₇, Graded structure.

36001349
Spectroscopic characterization of ultrashort laser driven targets incorporating both Boltzmann and particle-in-cell models
Sherrill, M. E.*; Abdallah, J.*; Csanak, G.*; Dodd, E. S.*; Fukuda, Yuji; Akahane, Yutaka; Aoyama, Makoto; Inoue, Norihiro*; Ueda, Hideki*; Yamakawa, Koichi; Faenov, A. Y.; Magunov, A. I.*; Pikuz, T. A.*; Skobelev, I. Y.*
High-Power Laser Ablation VII (Proceedings of SPIE Volume 7005) , p.70051R_1-70051R_11(2008) ; (JAEA-J 04652)

A model that solves simultaneously both the electron and atomic kinetics was used to generate synthetic X-ray spectra to characterize high intensity ultrashort-laser-driven target experiments. A particle-in-cell simulation was used to model the laser interaction for both cluster and foil targets and provided the initial electron energy distribution function (EEDF) for a Boltzmann solver. Though this model suggests that both Ar cluster and Ti foil plasmas are held in a highly non-equilibrium state for both the EEDF and the ion level populations for several picoseconds, the spectral line features of the foil experiment was shown to evolve too quickly to be seen by current ultrafast time resolved spectrometers.

36001350
Photo- and radiation induced reactions of melatonin by laser photolysis and pulse radiolysis
Lin, M.; He, H.*; Katsumura, Yosuke
Melatonin; From Molecules to Therapy , p.369-385(2007) ; (JAEA-J 04653)

Melatonin has been receiving more and more attention because of its physiological functions such as the treatment of jet lag and insomnia, and a miraculous drug of antitumor and anti-aging. It has been also suggested to act as an efficient free radical scavenger. In this chapter, we summarize the studies on the spectral properties and kinetic behaviors of the transient species of melatonin by laser photolysis and pulse radiolysis techniques.

36001351
J-PARC RCS non-linear frequency sweep analysis
Schnase, A.; Anami, Shozo*; Ezura, Eiji*; Haga, Kaiichi*; Hara, Keigo*; Hasegawa, Katsushi; Nomura, Masahiro; Omori, Chihiro*; Takagi, Akira*; Tamura, Fumihiko; Toda, Makoto*; Yamamoto, Masanobu; Yoshii, Masahito*
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM) , p.346-348(2008) ; (JAEA-J 04654)

A standard way to measure the transfer function of a system of amplifier and cavity uses a network analyzer and a linear frequency sweep. However, to check the transfer function of the broadband (Q=2) RCS RF system, we analyze several harmonics at same time under real high power ramp conditions. A pattern driven DDS generates frequency and amplitude like in accelerator operation. During the 20ms acceleration time, a large memory oscilloscope captures the RF-signals. The data are processed offline like down conversion in a multi-harmonic LLRF-system, giving multi-harmonic amplitude and phase information. With this setup we could find and cure resonances before installation to the tunnel. RCS is in the commissioning phase and has reached the milestone of acceleration to final energy and beam extraction. 10 RF systems are in operation. The LLRF-system controls fundamental h(2) and 2nd harmonic h(4). The multiharmonic analysis allows to check the RF system behavior also at other harmonics.

36001352
Acceleration voltage pattern for J-PARC RCS
Yamamoto, Masanobu; Hasegawa, Katsushi; Nomura, Masahiro; Schnase, A.; Tamura, Fumihiko; Anami, Shozo*; Ezura, Eiji*; Hara, Keigo*; Omori, Chihiro*; Takagi, Akira*; Toda, Makoto*; Yoshii, Masahito*
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM) , p.379-381(2008) ; (JAEA-J 04655)

The calculation code for the acceleration voltage pattern is usually based on the differential equation of the longitudinal synchrotron motion. We have developed the code based on the forward-difference equation which satisfies the synchronization with the bending magnetic field ramping accurately. This is very useful especially at the rapid cycling synchrotron where the ramping rate is high.

36001353
Study on chemical reactivity control of liquid sodium; Development of nano-fluid and its property and applicability to FBR plant
Saito, Junichi; Ara, Kuniaki; Sugiyama, Kenichiro*; Kitagawa, Hiroshi*; Nakano, Haruyuki*; Ogata, Kan*; Yoshioka, Naoki*
Proceedings of 16th International Conference on Nuclear Engineering (ICONE-16) (CD-ROM) , 4p.(2008) ; (JAEA-J 04656)

36001354
Dynamic strength evaluation of straight pipe using energy balance method
Minagawa, Keisuke*; Fujita, Satoshi*; Kitamura, Seiji; Okamura, Shigeki
Proceedings of 2008 ASME Pressure Vessels and Piping Conference (PVP 2008) (CD-ROM) , 6p.(2008) ; (JAEA-J 04659)

The ultimate strength of a mechanical structure is investigated from a viewpoint of the energy balance equation. The energy balance is adequate for an investigation into the influence of cumulative load. Authors have already confirmed a relationship between fatigue failure and the input energy from results of experiments using simple single degree of freedom models in a previous study. In this paper, straight pipe models are adopted, and the relationship between fatigue failure and the input energy is investigated. The investigation is implemented by forced vibration experiments that lead the experimental model to fatigue failure. As a result of the experiment, much input energy for failure is needed in case of small input level. This tendency is same as the result of the previous study using simple single degree of freedom model. Therefore it is expected that any actual piping satisfy this tendency, and time for failure can be expected by using energy balance.

36001355
Spectra thermal fatigue tests under frequency controlled fluid temperature variation; Superposed sinusoidal temperature fluctuations tests
Kawasaki, Nobuchika; Takasho, Hideki*; Kobayashi, Sumio; Hasebe, Shinichi; Kasahara, Naoto
Proceedings of 2008 ASME Pressure Vessels and Piping Conference (PVP 2008) (CD-ROM) , 9p.(2008) ; (JAEA-J 04660)

To clarify frequency-dependent attenuation effects of fluid temperature fluctuation on fatigue strength, thermal fatigue strength tests subjected to superposed sinusoidal temperature fluctuations were performed by the SPECTRA test facility. After these fatigue tests, cylindrical test pieces were cut away from the test loop, and cracks were observed on the inner surface of the test pieces. Fatigue lives at crack initiation positions were evaluated based on the test conditions. Adopting power spectrum density functions and frequency transfer functions, fatigue lives were predicted within a factor 3.

36001356
Stress mitigation design of tubesheets with consideration of thermal stress inducement mechanism
Ando, Masanori; Takasho, Hideki*; Kawasaki, Nobuchika; Kasahara, Naoto
Proceedings of 2008 ASME Pressure Vessels and Piping Conference (PVP 2008) (CD-ROM) , 10p.(2008) ; (JAEA-J 04661)

Adoption of double-wall-straight tube steam generators made of Mod.9Cr-1Mo steel is planned for next generation fast breeder reactors in Japan. One of the major concerns relevant to the SG is structural integrity of tubesheets. In the reactor transient operation, thermal stress is induced by the temperature distribution in tubesheet and the magnitude of it depends on configurations of tubesheet. Stress generation mechanism of tubesheets was revealed through Finite Element analysis. Semi-spherical tubesheet models were investigated for the first survey of the thermal stress mechanism. As calculated results, semi-spherical tubesheet model gave the extensive peak stress around the outermost hole. Based on the those stress generation mechanism, authors proposed a stress mitigated tubesheet. It is center flatted spherical tubesheet as improved configuration.

36001357
Oscillation frequency and deformation of levitated droplets
Watanabe, Tadashi
Proceedings of 22nd International Congress of Theoretical and Applied Mechanics (ICTAM 2008) (CD-ROM) , 2p.(2008) ; (JAEA-J 04662)

Three-dimensional numerical simulations of shape oscillations and rotations of levitated droplets are performed using the level set method as one of the developments of element technologies for evaluation and analyses of nuclear plants. Levitated droplets are used to measure material properties of molten metal, since the effects of container wall are eliminated. In this study, the effects of oscillation and rotation are simultaneously taken into account, and the relation between the oscillation frequency and the deformation of the droplets are studied. The droplet deformation is found to be closely related to the frequency shift of the shape oscillation. It is indicated that the measurement of the correct frequency, which is necessary for the determination of the correct surface tension, would be possible by monitoring the aspect ratio of the oscillating-rotating droplet and by controlling the rotation rate.

36001358
High performance computing for eigenvalue solver in density-matrix renormalization group method; Parallelization of the hamiltonian matrix-vector multiplication
Yamada, Susumu; Okumura, Masahiko; Machida, Masahiko
Proceedings of 8th International Meeting on High Performance Computing for Computational Science (VECPAR '08) (CD-ROM) , p.448-454(2008) ; (JAEA-J 04663)

36001359
Application of microwave heating to MOX fuel production and its contribution to Japanese energy strategy
Suzuki, Masahiro; Ishii, Katsunori; Yamamoto, Takuma; Kihara, Yoshiyuki; Kato, Yoshiyuki; Kurita, Tsutomu; Yoshimoto, Katsunobu; Fujii, Kanichi
Proceedings of Global Congress on Microwave Energy Applications (GCMEA 2008/MAJIC 1st) , p.501-504(2008) ; (JAEA-J 04664)

The natural resources, oil and uranium, would dry up around the midway of this century. FBR cycle most probably rescues this difficult situation. Mass production of MOX fuel for FBR, therefore, is the supreme subject to Japanese energy strategy. For this subject, we are attacking with Microwave heating technology. Up to present, we have succeeded to produce excellent PuO₂/UO₂ bulk, 2 kgMOX/batch, advancing toward the mass production target, 5 kgU/h for one batch.

36001360
Parallel computing of directly-extended density-matrix renormalization group to two-dimensional strongly correlated quantum systems
Yamada, Susumu; Okumura, Masahiko; Machida, Masahiko
Proceedings of IASTED International Conference on Parallel and Distributed Computing and Networks (PDCN 2008) , p.175-180(2008) ; (JAEA-J 04665)

The Density Matrix Renormalization Group (DMRG) method is widely used by computational physicists as a high accuracy tool to explore the ground state of large quantum lattice systems. However, the reliable results by DMRG are limited only for 1-D or two-leg ladder models in spite of a great demand for 2-D system. The reason is that the direct extension to 2-D requires an enormous memory space while the technical extension based on 1-D algorithm does not keep the accuracy in 1-D systems. Therefore, we parallelize the direct 2-D DMRG code on a large-scale supercomputer and examine the accuracy and the performance for typical lattice models, i.e., Heisenberg and Hubbard models. The parallelization is mainly made on the multiplication of the Hamiltonian matrix and vectors. We find that the parallelization efficiency, i.e., the speed up ratio with increasing the number of CPU, shows a good one as the number of states kept increases. This result is promising for future 2-D parallel DMRG simulations.

36001361
Measurement of total γ absorption for high energy γ rays
Kitatani, Fumito; Harada, Hideo; Hara, Kaoru; Utsunomiya, Hiroaki*; Goko, Shinji*; Kaihori, Takeshi*; Toyokawa, Hiroyuki*
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.1 , p.123-126(2008) ; (JAEA-J 04666)

Total γ absorption cross sections are most important data used in various fields related to the application of γ rays. However, the measurements of the total γ absorption cross section were difficult for high energy γ rays since there were no suitable γ ray sources. Recently, the nuclear photo-absorption measurement system using the laser-Compton backscattering (LCS) γ rays and the high-resolution high-energy photon spectrometer (HHS) were developed. We have utilized the system to measure the total γ absorption cross section, that is, the sum of the atomic and nuclear interactions. The total γ absorption cross sections at 10 MeV for Al and Cu have been measured with the system. The preliminary results show that the obtained values agree fairly with the theoretical.

36001362
Systematical nucleon-induced optical model analysis for medium and heavy nuclei with coupled-channel framework
Kunieda, Satoshi; Chiba, Satoshi; Shibata, Keiichi; Ichihara, Akira; Sukhovitskij, E.*
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.1 , p.227-230(2008) ; (JAEA-J 04667)

The optical model analyses were carried out for nucleon-induced reactions on medium and heavy nuclei from 1 keV to 200 MeV. The coupled-channels method based on the rigid-rotator model was employed as an initial approach. It was found that the coupled-channels analyses were indispensable to obtain a global formulation of optical potential. In addition to this, the coupled-channels calculations based on the soft-rotator model was applied to analyses for various even-even fission product isotopes. They reproduced measured cross sections better than the rigid-rotator model in many cases. Though the latter is our ongoing study, we show the advantage of coupled-channels calculations and the applicability of the soft-rotator model in this conference.

36001363
Experimental approach to flow field evaluation in upper plenum of reactor vessel for innovative sodium cooled fast reactor
Kimura, Nobuyuki; Hayashi, Kenji; Kamide, Hideki
Proceedings of OECD/NEA Workshop on Experiments and CFD Code Applications to Nuclear Reactor Safety (XCFD4NRS) (CD-ROM) , 12p.(2008) ; (JAEA-J 04668)

In Japan Atomic Energy Agency, an innovative sodium cooled fast reactor of 1500MWe class, JSFR, has been investigated on the Fast Reactor Cycle Technology Development project. A compact reactor vessel (R/V) and a column type upper inner structure with a radial slit for an arm of a fuel-handling machine are adopted. These result in increase of the spatial-averaged velocity on the horizontal cross section of the R/V by factor of 2.5. These high velocities may cause gas entrainment at the free surface in the upper plenum and also the cavitations. Therefore horizontal dipped plates (D/P) are set below the free surface to prevent the gas entrainment. We performed two water experiments using an 1/10th scaled full-sector model of the upper plenum of R/V and a large scaled partial model. The flow optimization in the upper plenum was performed in the full-sector model. It was observed in the large scaled model that the gas entrainment occurred under the extreme velocity conditions which were far from the rated condition in the reactor design of JSFR. Consequently, there is a chance for this design of the compact reactor vessel to suppress the gas entrainment and cavitation.

36001364
Tritium generation in lithium ceramics Li₂TiO₃ for fusion reactor blanket
Tazhibayeva, I. L.*; Kenzhin, E. A.*; Kulsartov, T. V.*; Kuykubaeva, A. A.*; Shestakov, V.*; Chikhray, E.*; Gizatulin, S.*; Maksimkin, O. P.*; Beckman, I. N.*; Kawamura, Hiroshi; Tsuchiya, Kunihiko
Questions of Atomic Science and Technology, 2 , p.3-11(2008) ; (JAEA-J 04669)

Lithium titanate (Li₂TiO₃) was chosen as a tentative reference material from viewpoints of good tritium recovery at low temperatures and of low tritium inventory and chemical stability for the breeding blanket in fusion reactors. The results of the irradiation tests of Li₂TiO₃ in the WWR-K of NNC-RK are described in this paper. 96at% ⁶Li-enriched Li₂TiO₃ pebbles and disks were prepared as the irradiation specimens and these specimens were irradiated during 220 days (5350 hours) at the reactor power of 6 MWt. Tritium release was measured continuously during irradiation tests and tritium release properties were evaluated. The mechanics describing generation and release of tritium from the irradiated Li₂TiO₃ were analyzed. There was estimated tritium loss due to recoil energy and binding of tritium in HTO, and there was calculated stationary tritium release due to diffusion under constant temperature and under thermal cycling.

36001365
Comprehensive education and training activities at JAEA Nuclear Technology and Education Center
Sugimoto, Jun; Sakamoto, Ryuichi; Kushita, Kohei; Arai, Nobuyoshi; Hattori, Takamitsu; Matsuda, Kenji; Ikuta, Yuko; Sato, Koichi
Transactions of NESTet 2008 (CD-ROM) , 6p.(2008) ; (JAEA-J 04670)

Nuclear human resources development (HRD) in Japan has been identified as one of the most important issues these years in nuclear society, mostly due to the decrease of nuclear engineers in industries and students in universities, and to the difficulties of technical transfers. Nuclear Technology and Education Center (NuTEC) at Japan Atomic Energy Agency (JAEA) aims at comprehensive nuclear education and training activities, which cover (1) education and training for domestic nuclear engineers, (2) cooperation with universities and (3) international cooperation. The main feature of NuTEC's training programs is that the curricula places emphasis on the laboratory exercise with well-equipped training facilities and expertise of lecturers mostly from JAEA. The wide spectrum of cooperative activities have been pursued with universities, which includes newly developed remote-education system, and also with international organizations, such as with FNCA countries and IAEA.

36001366
Contermeasure for the reduction of groundwater inflow due to the construction of the Mizunami Underground Research Laboratory (in Japanese)
Takeuchi, Shinji; Hara, Masato; Mikake, Shinichiro; Tsuruta, Tadahiko; Ikeda, Koki; Yamamoto, Masaru
Dai-12-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (CD-ROM) , p.189-196(2008) ; (JAEA-J 04671)

The Mizunami Underground Research Laboratory (MIU) is currently being constructed. During its construction, water inflow into the shafts of the MIU has been increasing and affecting the project progress. In order to reduce the water inflow into the shafts, pilot borehole investigations and pre-excavation grouting have been planned. The pilot borehole investigations has been conducted from the shaft bottom at bothe of the Main (180mbGL) and Ventilation (191mbGL) shafts, respectively. The pre-excavation grouting has been undertaken in the Ventilation Shaft. The results of the investigations have showed applicability of several techniques applied.

36001367
Development of elevated temperature structural design method for fast reactor vessels, 1; Concept of development in strength evaluation (in Japanese)
Kawasaki, Nobuchika; Nagae, Yuji; Kato, Shoichi; Ando, Masanori; Kasahara, Naoto
Dai-13-Kai Doryoku, Enerugi Gijutsu Shimpojiumu Koen Rombunshu , p.507-510(2008) ; (JAEA-J 04672)

Concept of development in strength evaluation for fast reactor vessels was introduced. Based on the characteristics of reactor vessel for developing fast breeder reactor, creep-fatigue strength and ratcheting deformation criterion are under developing. For the creep-fatigue strength, intermediate dwelling creep-fatigue, aging effect and strain concentration are selected as developing items. The ratcheting deformation criterion will be determined by ratcheting fatigue and ratcheting creep-fatigue test results.

36001368
Applying the remote maintenance technology to the large scale hot laboratory (in Japanese)
Sakamoto, Naoki; Yoshikawa, Katsunori; Kushida, Naoya; Nakamura, Yasuo; Sukegawa, Kiyoshi*
Nippon Hozen Gakkai Dai-5-Kai Gakujutsu Koenkai Yoshishu , p.226-230(2008) ; (JAEA-J 04674)

36001369
Status of J-PARC ring RF systems
Schnase, A.; Nomura, Masahiro; Tamura, Fumihiko; Yamamoto, Masanobu; Haga, Koichi; Hasegawa, Katsushi; Yoshii, Masahito*; Omori, Chihiro*; Hara, Keigo*; Toda, Makoto*; Takagi, Akira*; Anami, Shozo*; Ezura, Eiji*
Proceedings of 4th Annual Meeting of Particle Accelerator Society of Japan and 32nd Linear Accelerator Meeting in Japan (CD-ROM) , p.212-214(2007) ; (JAEA-J 04675)

We present the Status of the J-PARC RF systems of the Rapid Cycling Synchrotron (RCS) and the 50 GeV Main-ring (MR). The RCS RF systems are prepared for beam commissioning scheduled in September 2007. The 10 cavities, amplifiers and power supplies are installed in the RCS tunnel. The cavities are loaded with improved uncut cores. The parallel inductor for Q=2 was successfully tested and installed in all systems. The long-term performance and reliability of each of the 180 cores was checked for at least 300 hours. One set of cores performed a 1000-hour power test. We operate the cavities in the tunnel together with the LLRF system to check the interoperability and prepare for 25 Hz RCS operation. Some issue related to noise and grounding was solved. Unwanted resonances of the tube amplifier in the RCS frequency range were analyzed and removed. For the MR RF systems, we have decided to employ the diamond polishing technique for cut-core production. The long run high power tests with cut-core loaded cavities are ongoing. We prepare for installation start to MR in September 2007.

36001370
Development of a methodology to evaluate characteristics of energy technology by conjoint analysis (in Japanese)
Hiwatari, Ryoji*; Okano, Kunihiko*; Asaoka, Yoshiyuki*; Nagano, Koji*; Ogawa, Yuichi*; Kato, Takaaki*; Tobita, Kenji; Norimatsu, Takayoshi*
Denryoku Chuo Kenkyusho Hokoku (L07012) , p.34(2008) ; (JAEA-J 04676)

Key to take public acceptance into account on the energy system is how to evaluate and compare quantitatively the merits and the demerits of each energy system from the public viewpoint. For this purpose, a method to evaluate the property of energy technology is developed based on the conjoint analysis technique. Based on the statistical method, utility values for energy abundance, environmental load (i.e. CO₂ emission), stability of supply, sense of security, and other features as well as economic performance, are estimated from several thousands of choice experiments to more than 1600 respondents volunteered in the study. The basic methodology developed in this study establishes the first step to assess energy technology quantitatively on a common standard, and needs further integration with other factors, such as waste generation other than CO₂ emission.

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