JAEA Abstracts

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

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

May 2008

36000658
Characterization of boron carbonitride (BCN) thin films deposited by radiofrequency and microwave plasma enhanced chemical vapor deposition
Mannan, M. A.*; Nagano, Masamitsu*; Shigezumi, Kazuya*; Kida, Tetsuya*; Hirao, Norie*; Baba, Yuji
American Journal of Applied Sciences 5(6), p.736-741(2008) ; (JAEA-J 03917)

Boron carbonitride thin films with a thickness of 4 micrometer were synthesized on Si(100) substrate by radiofrequency and microwave plasma enhanced vapor deposition using trimethylamine boran as a precursor. It has bee observed that the films were adhered well to the silicon substrate even after being broken mechanically. X-ray diffraction (XRD) and filed emission scanning electron microscopy (FE-SEM) results showed that the films were amorphous and the surface was rough with inhomogeneous microstructure. On the basis of the X-ray photoelectron spectra (XPS), it was elucidated that B, C and N atoms have different chemical bonds such as B-N, B-C and C-N.

36000659
Development of a chirped pulse amplification laser with zigzag slab Nd:glass amplifiers dedicated to X-ray laser research
Ochi, Yoshihiro; Hasegawa, Noboru; Kawachi, Tetsuya; Nagashima, Keisuke
Applied Optics 46(9), p.1500-1506(2007) ; (JAEA-J 03918)

A chirped pulse amplification laser with zigzag slab Nd:glass amplifiers dedicated to X-ray laser research is described. The laser provides a 1.6-ps duration pulse with ∼7 J energy at repetition rate of 0.1 Hz. The amplification is made in two steps: first 10×10 mm² beam is amplified from ∼mJ to ∼J in the first amplifier with image-relayed multi-pass amplification. Then the laser light is expanded to be 10×90 mm² and amplified up to >10 J in the second amplifier. The gain-saturated Ni-like silver laser at a wavelength of 13.9 nm has been successfully produced by this laser system.

36000660
Characterization of a high-brilliance soft X-ray laser at 13.9 nm by use of an oscillator-amplifier configuration
Nishikino, Masaharu; Hasegawa, Noboru; Kawachi, Tetsuya; Yamatani, Hiroshi; Sukegawa, Kota; Nagashima, Keisuke
Applied Optics 47(8), p.1129-1134(2008) ; (JAEA-J 03919)

We have demonstrated an X-ray laser with highly peak brilliance and highly spatial coherence at 13.9 nm. In order to generate the highly brilliant X-ray laser by using the oscillator-amplifier configuration, a seeding X-ray laser beam is amplified by a medium plasma with the high gain coefficient. The amplified X-ray laser with highly output is affected by the refraction in the gain medium plasma. However the amplified X-ray laser has very high peak brilliance of 5×10²⁶ photons/(s·mm²·mrad²·0.01%bandwidth) and large photon flux of 6.5×10¹⁰photons/pulse.

36000661
Integrated ELM simulation with edge MHD stability and transport of SOL-divertor plasmas
Hayashi, Nobuhiko; Takizuka, Tomonori; Aiba, Nobuyuki; Ozeki, Takahisa; Oyama, Naoyuki
Contributions to Plasma Physics 48(1-3), p.196-200(2008) ; (JAEA-J 03921)

The effect of the pressure profile on the energy loss caused by edge localized modes (ELMs) has been investigated by using an integrated simulation code TOPICS-IB based on a transport code with a stability code for the peeling-ballooning modes and a model for scrape-off-layer and divertor plasmas. The steep pressure gradient inside the pedestal top is found to broaden the region of the ELM enhanced transport through the broadening of eigenfunctions and enhance the ELM energy loss. The ELM energy loss in the simulation becomes larger than 15% of the pedestal energy, as is shown in the database of multi-machine experiments.

36000662
Effect of radial transport loss on the asymmetry of ELM heat flux
Takizuka, Tomonori; Oyama, Naoyuki; Hosokawa, Masanari*
Contributions to Plasma Physics 48(1-3), p.207-211(2008) ; (JAEA-J 03922)

36000663
Effect of oblieque magnetic field on release conditions of dust particle from plasma-facing wall
Tomita, Yukihiro*; Smirnov, R. D.*; Takizuka, Tomonori; Tskhakaya, D.*
Contributions to Plasma Physics 48(1-3), p.285-289(2008) ; (JAEA-J 03923)

36000664
Recognition of lysine residues on protein surfaces using calixarenes and its application
Oshima, Tatsuya*; Baba, Yoshinari*; Shimojo, Kojiro; Goto, Masahiro*
Current Drug Discovery Technologies 4(4), p.220-228(2007) ; (JAEA-J 03924)

A macrocyclic calix[6]arene carboxylic acid derivative is found to extract lysine-rich protein cytochrome c from aqueous media into organic media through the complexation between the calixarene molecules and lysine residues on the surface of the protein. This article summarizes both the mechanism of protein extraction by the calixarene as well as the potential applications of the extraction process. The extraction process can be used for the purification of proteins through selective extraction and back-extraction under optimized conditions. On the other hand, the extracted protein exhibits enzymatic activity in organic media. The formation of a supramolecular complex by recognizing the residues on a protein surface can be construed as a novel recognition and/or modification method for biomacromolecules.

36000665
Modulatory effect of ionizing radiation on food-NaCl associative learning; The Role of γ subunit of G protein in Caenorhabditis elegans
Sakashita, Tetsuya; Hamada, Nobuyuki*; Ikeda, Daisuke*; Yanase, Sumino*; Suzuki, Michiyo; Ishii, Naoaki*; Kobayashi, Yasuhiko
FASEB Journal 22(3), p.713-720(2008) ; (JAEA-J 03927)

We analyzed the effects of ionizing radiation (IR) on a food-NaCl associative learning paradigm of adult Caenorhabditis elegans, and observed that a decrease in chemotaxis toward NaCl occurs only after combined starvation and exposure to NaCl. Exposure to IR induced an additional decrease in chemotaxis immediately after an acute dose in the transition stage of the food-NaCl associative learning. Strikingly, chronic irradiation induced negative chemotaxis in the exposed animals, i.e., the primary avoidance response. IR-induced additional decreases in chemotaxis following acute and chronic irradiations were significantly suppressed in the gpc-1 mutant, which was defective in GPC-1. Chemotaxis to cAMP, but not to lysine and benzaldehyde, was influenced by IR during the food-NaCl associative learning. Our novel findings suggest that IR behaves as a modulator in the food-NaCl associative learning via C. elegans GPC-1 and a specific neuronal network.

36000666
Residue 134 determines the dimer-tetramer assembly of nucleoside diphosphate kinase from moderately halophilic bacteria
Tokunaga, Hiroko*; Ishibashi, Matsujiro*; Arisaka, Fimio*; Arai, Shigeki; Kuroki, Ryota; Arakawa, Tsutomu*; Tokunaga, Masao*
FEBS Letters 582(7), p.1049-1054(2008) ; (JAEA-J 03928)

Halomonas nucleoside diphosphate kinase (HaNDK) forms a dimeric assembly and Pseudomonas NDK (PaNDK) forms a tetrameric assembly. The mutation of Glu134 to Ala in HaNDK resulted in conversion of the native dimeric structure to the tetramer assembly. Conversely, the mutation of Ala134 to Glu in PaNDK leads to conversion from tetramer to dimer assembly, indicating that a single amino acid substitution at position 134 results in an alteration of the oligomeric structure of NDK. Modeling structure of HaNDK and PaNDK, based on the crystal structure of Myxococcus NDK, suggested sufficient repulsion by Glu134 to disrupt dimer-dimer interaction to form tetramer.

36000667
Impact of Auger recombination on charge collection of a 6H-SiC diode by heavy ions
Onoda, Shinobu; Oshima, Takeshi; Hirao, Toshio; Mishima, Kenta; Hishiki, Shigeomi; Iwamoto, Naoya; Kawano, Katsuyasu*
IEEE Transactions on Nuclear Science 54(6), p.2706-2713(2007) ; (JAEA-J 03929)

36000668
The Cost benefit of a light water reactor safety study in JAERI
Yanagisawa, Kazuaki
International Journal of Nuclear Governance, Economy and Ecology 2(2), p.212-223(2008) ; (JAEA-J 03931)

A cost benefit effect of use in nuclear energy, born as a result of JAEA research and development (R&D) works for 42-years. It is the reduction of nuclear accident compensation insurance (NACI) by reducing accident risk, which is related to LWR safety study. From economic viewpoint, the topic is classified as the reduction of opportunity loss (ROL). Here, the author wish to discuss about the reduction effect by NACI to all Japanese NPPs and the contribution of JAERI-LWR safety study o that reduction.

36000669
Solidus and liquidus of plutonium and uranium mixed oxide
Kato, Masato; Morimoto, Kyoichi; Sugata, Hiromasa*; Konashi, Kenji*; Kashimura, Motoaki; Abe, Tomoyuki
Journal of Alloys and Compounds 452(1), p.48-53(2008) ; (JAEA-J 03932)

Plutonium and uranium mixed oxide has been developed as a fuel of a fast reactor. The maximum temperature of the fuel pellet is limited within a design criterion to prevent fuel melting. So, the melting points of the mixed oxide have been investigated since the development of fast reactor started. However the measured data are limited. In this work, the melting points of (U1-yPuy)O_2-x (y: 0, 0.12, 0.2, 0.3, 0.4) were measured by the thermal arrest method. The evaluated melting point of this study underestimates in case of MOX with high Pu contents of 30% and 40%. The solidus of UO₂, (Pu_0.12U_0.88)O_2.00 and (Pu_0.2U_0.8)O_2.00 were determined to be 3128K, 3077K and 3052K, respectively. The solidus temperature of hypostoichiometric MOX slightly increased with decreasing O/M.

36000670
Thermal conductivity of (U,Pu,Am)O₂ solid solutions
Morimoto, Kyoichi; Kato, Masato; Ogasawara, Masahiro*; Kashimura, Motoaki; Abe, Tomoyuki
Journal of Alloys and Compounds 452(1), p.54-60(2008) ; (JAEA-J 03933)

Plutonium and uranium mixed oxide (MOX) fuel with high Pu content have been developed as a fuel of fast reactor (FR). As the storage time of Pu raw material between reprocessing and fabrication increases, americium content of the fabricated MOX fuel increases up to a few percent. In this work, the thermal conductivity of MOX fuel containing Am was investigated as a part of clarifying the effect of Am content on thermal physical properties. The pellets of (Am_0.007 Pu_0.3 U)O_2.00, (Am_0.02 Pu_0.3 U)O_2.00 and (Am_0.03 Pu_0.3 U)O_2.00 were prepared. The oxygen to metal ratio (O/M ratio) of sintered pellet was adjusted to 2.00. The thermal diffusivity measurement was carried out in the range of temperature from 900 K to 1700 K by the laser flash method, and thermal conductivity of these pellets was evaluated. The heat capacity for evaluating thermal conductivity was derived from heat capacity of UO₂, PuO₂ and AmO₂ by using the Kopp-Neumann rule.

36000671
Structural studies of lanthanide nitrate-N,N'-dimethyl-N,N'-diphenylpyridine-2,6-dicarboxyamide complexes
Fujiwara, Asako; Nakano, Yoshiharu*; Yaita, Tsuyoshi; Okuno, Kenji*
Journal of Alloys and Compounds 456(1-2), p.429-435(2008) ; (JAEA-J 03934)

The tridentate ligand N,N'-dimethyl-N,N'-diphenylpyridine-2,6-dicarboxyamide (DMDPhPDA) and the corresponding lanthanum complex [La(NO₃)₃(DMDPhPDA)₂] have been prepared and structurally characterised. In the lanthanum complex, two DMDPhPDA molecules coordinated to La(III) in a tridentate fashion and to three nitrate ions in a bidentate fashion make the lanthanum atom 12-coordinate. The stability constants determined by spectrophotometric titration suggest that [Ln(DMDPhPDA)₂]³⁺ is the primary product in nitrate media and [Ln(DMDPhPDA)₃]³⁺ is difficult to form. However, [Ln(DMDPhPDA)₂]³⁺ could not be distinguished in ¹³C NMR spectra. The ¹³C NMR titration results imply that a fast ligand exchange process takes place.

36000672
The Search for magnetic order in δ-Pu metal using muon spin relaxation
Heffner, R. H.; Oishi, Kazuki; Fluss, M. J.*; Morris, G. D.*; MacLaughlin, D. E.*; Shu, L.*; Chung, B. W.*; McCall, S. K.*; Bauer, E. D.*; Sarrao, J. L.*; Ito, Takashi; Higemoto, Wataru
Journal of Alloys and Compounds 444-445, p.80-83(2007) ; (JAEA-J 03936)

We summarize the results of muon spin relaxation (μSR) measurements carried out inα- and δ-Pu and in the superconducting state ofPuCoGa₅. In Pu metal, interest has centered on whether or not magnetic order exists in the hightemperature fcc δ phase,The Pu metal studies were designed to search for evidence of magnetic ordering, andhave set the most stringent limits to date for the ordered moment. In PuCoGa₅ the temperature dependence of themagnetic penetration depth λ(T) was investigated in a fresh sample and again in the same sampleafter 400 days of aging. We find λ(T)∝ T for T < Tc/2, indicating a line of nodes in thesuperconducting order parameter. Remarkably, the temperature dependence of λ(T) is littlechanged even after significant radiation damage.

36000673
NMR studies of actinide dioxides
Tokunaga, Yo; Sakai, Hironori; Fujimoto, Tatsuya; Kambe, Shinsaku; Walstedt, R. E.*; Ikushima, Kenji*; Yasuoka, Hiroshi; Aoki, Dai*; Homma, Yoshiya*; Haga, Yoshinori; Matsuda, Tatsuma; Ikeda, Shugo; Yamamoto, Etsuji; Nakamura, Akio; Shiokawa, Yoshinobu*; Nakajima, Kunihisa; Arai, Yasuo; Onuki, Yoshichika
Journal of Alloys and Compounds 444-445, p.241-245(2007) ; (JAEA-J 03937)

In this paper, we present our recent NMR works on Neptunium and Plutonium compounds. In order to elucidate the nature of the exotic multipolar ordered phase of NpO₂, we have initiated the first NMR measurements on this system. We have shown that direct observation of multipole order parameters is possible by means of NMR. Our NMR results provide further insight into the microscopic nature of multipole phase transitions in f-electron systems. We have also performed ^69,71Ga NMR/NQR studies on a single crystal of PuRhGa₅. From the temperature dependence of the spin-lattice relaxation rate (1/T₁), we have found that PuRhGa₅ is an unconventional superconductor having an anisotropic superconducting (SC) gap 2Δ(0)=5K_BT_c. Furthermore, we have confirmed the Knight shift to be decreased below T_c. This gives strong evidence for spin singlet SC pairing.

36000674
Study on valence of Pu, Np and Tc in nitric acid after electrolytic reduction
Hoshi, Harutaka*; Wei, Y.-Z.*; Kumagai, Mikio*; Asakura, Toshihide; Morita, Yasuji
Journal of Alloys and Compounds 444-445, p.663-667(2007) ; (JAEA-J 03938)

36000675
Dynamical thermal conductivity of argon crystal
Kaburaki, Hideo; Li, J.*; Yip, S.*; Kimizuka, Hajime*
Journal of Applied Physics 102(4), p.043514_1-043514_6(2007) ; (JAEA-J 03939)

The thermal conductivity of a rare-gas crystal (Ar) is computed using equilibrium molecular dynamics in conjunction with the Green-Kubo linear response formalism, and the Lennard-Jones potential with an appropriately long cutoff. Besides predicting absolute values of the conductivity from low temperature up to the liquid, the approach allows heat conduction to be understood as a dynamical process through the temporal behavior of the heat current correlation function. At low temperatures the correlation function shows a characteristic two-stage decay, a short-time relaxation which we attribute to single-particle motions in a local environment, and a more extended component corresponding to collective atomic motions (phonons). As temperature increases the second correlation component diminishes much faster than the first component, indicating a transition from mainly phase-coherent phonon transport to mainly phase-incoherent interatomic energy transfer in solids.

36000676
Optimization of the parallel finite element method for the earth simulator
Kushida, Noriyuki; Okuda, Hiroshi*
Journal of Computational Science and Technology (Internet) 2(1), p.81-91(2008) ; (JAEA-J 03941)

Since the earth simulator consists of 640 SMP nodes, each of which has eight vector processors, there are three levels of hierarchical parallelization methods: inter-node, intra-node, and vectorization. In the present study, intra-node and vectorization were added on the inter-node parallelized FEM code, and the performance was examined. As a result, we achieved 30 times acceleration at maximum. Additionally, we achieved 10 TeraFLOPS, which was approximately 30% of peak performance, when we used 4,096 processors.

36000677
Solid-phase grain growth of In₂O₃ at high pressures and temperatures
Saito, Hiroyuki; Utsumi, Wataru; Aoki, Katsutoshi
Journal of Crystal Growth 310(7-9), p.2295-2297(2008) ; (JAEA-J 03942)

We determined the pressure-temperature diagram at pressures up to 10 GPa and temperatures of 20-2000 °C by in situ X-ray diffraction measurement. The decomposition temperature rose from 1250 to 1700 °C as the pressure increased from 2.0 to 4.0 GPa. It remained at about 1700 °C at higher pressures. The cubic structure transformed into a rhombohedral corundum structure at 4.0 GPa and 1600 °C. The phase boundary had a slightly negative slope and its extrapolation provided an estimated transition pressure of 12 GPa at room temperature. Rapid grain growth was observed near the phase boundary in the rhombohedral region at temperatures around 1000 °C still sufficiently below the decomposition temperature. The single crystals of the high-pressure rhombohedral phase were recovered at ambient conditions. The size of the chunk crystals was about 100 μm.

36000678
Postcollisional exhumation history of the Tanzawa Tonalite Complex, inferred from (U-Th)/He thermochronology and fission track analysis
Yamada, Kunimi; Tagami, Takahiro*
Journal of Geophysical Research 113(3), p.B03402_1-B03402_10(2008) ; (JAEA-J 03943)

We performed new thermochronometry for the Tanzawa Tonalite Complex to investigate the exhumation history caused by arc-arc collision. Typical (U-Th)/He ages were 2.0 ± 0.2 Ma on apatite and 3.3 ± 0.2 Ma on zircon and 4.5 to 6.9 Ma on zircon using the fission-track method. The exhumation rate has been calculated to be 0.5 to 1.5 mm/yr from ∼ 7 to 3.3 Ma, ∼ 2 mm/yr from 3.3 to 2.0 Ma and ∼ 0.8 mm/yr from 2.0 to 0 Ma with an assumed geothermal gradient of 40°C/km. The exhumation rate has not changed significantly despite the simultaneous tectonic changes around the Tanzawa Mountains after ∼ 7 Ma.

36000679
Protein expression of Saccharomyces cerevisiae in response to uranium exposure
Sakamoto, Fuminori; Nankawa, Takuya; Kozai, Naofumi; Fujii, Tsutomu*; Iefuji, Haruyuki*; Francis, A. J.; Onuki, Toshihiko
Journal of Nuclear and Radiochemical Sciences 8(2), p.133-136(2007) ; (JAEA-J 03944)

Protein expression of Saccharomyces cerevisiae grown in the medium containing ²³⁸U(VI) and ²³³U(VI) was examined by two-dimensional gel electrophoresis. S. cerevisiae of BY4743 was grown in medium containing ²³⁸U of 0, 2.0, and 5.0 × 10^-4 M or ²³³U of 2.5 × 10^-6 (radioactivity was higher by 350 times than 2.0 × 10^-4 M ²³⁸U) and 5.0 × 10^-6 M for 112 h at 30°C. The growths of the yeast grown in the above media were in the following order: control > 2.5 × 10^-6 M ²³³U > 2.0 × 10^-4 M ²³⁸U > 5.0 × 10^-6 M ²³³U > 5.0 × 10^-4 M ²³⁸U. This result indicated that not only radiological but also chemical effect of U reduced the growth of the yeast. The concentrations of U in the medium containing ²³⁸U or ²³³U decreased, suggesting U accumulation by the yeast cells. The 2-D gel electrophoresis analysis showed the appearance of several spots after exposure to ²³⁸U or to ²³³U but not in the control containing no uranium. These results show that the yeast cells exposed to U express several specific proteins.

36000680
EXAFS and XANES studies of americium dioxide with fluorite structure
Nishi, Tsuyoshi; Nakada, Masami; Ito, Akinori; Suzuki, Chikashi; Hirata, Masaru; Akabori, Mitsuo
Journal of Nuclear Materials 374(3), p.339-343(2008) ; (JAEA-J 03945)

EXAFS and XANES analysis were applied in a study of americium dioxide (AmO₂) with fluorite structure. EXAFS result for Am-L₃ absorption edge of AmO₂ was good agreement with the long-ranged structural data from X-ray diffraction analysis. In order to characterize XANES in aspect of the electronic structure, the theoretical assignment for the AmO₂ was performed with the relativistic DV-Xα molecular orbital method. The calculated XANES spectrum well reproduced the experimental spectrum. The theoretical assignment of the XANES spectra is very useful for the development of MA-MOX fuel for the future nuclear fuel cycle.

36000681
Thermal conductivities of hypostoichiometric (U, Pu, Am)O_2-x oxide
Morimoto, Kyoichi; Kato, Masato; Ogasawara, Masahiro*; Kashimura, Motoaki
Journal of Nuclear Materials 374(3), p.378-385(2008) ; (JAEA-J 03946)

The thermal conductivities of (U_0.68Pu_0.3Am_0.02)O_2-x solid solutions (x = 0.0 - 0.1) were studied at temperatures from 900 to 1773 K. Thermal conductivities were obtained from the thermal diffusivity measured by laser flash method. The thermal conductivities obtained experimentally up to about 1400K could be expressed by a classical phonon transport model, λ = (A+BT)^-1, A(x) = 2.89×x + 2.24×10^-2 (m K/W) and B(x) = (- 6.70×x + 2.48) × 10^-4 (m/W). The experimental values of A showed a good agreement with theoretical predictions. The experimental values of B could be fairly expressed by the theoretical prediction in the region x < 0.04, but not deviated from the ones in the region x > 0.04. Although this reason could not be understood well, it is most likely that the uncertainty in the measurement of melting temperature cause this difference.

36000682
Water corrosion resistance of ODS ferritic-martensitic steel tubes
Narita, Takeshi; Ukai, Shigeharu; Kaito, Takeji; Otsuka, Satoshi; Matsuda, Yasushi*
Journal of Nuclear Science and Technology 45(2), p.99-102(2008) ; (JAEA-J 03947)

The oxide dispersion strengthened (ODS) ferritic-martensitic steels are being developing for application as advanced fast reactor cladding and fusion blanket materials, in order to allow increased operation temperature. Water corrosion test of ODS ferritic-martensitic steels was conducted under a controlled alkali water environment to evaluate the water corrosion behavior, comparing to conventional 17 mass% Cr austenitic stainless steel (PNC316) and 11 mass% Cr ferritic-martensitic stainless steel (PNC-FMS). It was showed that 9Cr-ODS martensitic steel and 12Cr-ODS ferritic steel have superior water corrosion resistance, and comparable to that of PNC316 and PNC-FMS at 333K for 1,000h under varying pH of 8.4, 10, 12.

36000683
Measurement and analysis of neutron-induced alpha particle emission double-differential cross section of carbon at 14.2 MeV
Kondo, Keitaro; Murata, Isao*; Ochiai, Kentaro; Kubota, Naoyoshi*; Miyamaru, Hiroyuki*; Konno, Chikara; Nishitani, Takeo
Journal of Nuclear Science and Technology 45(2), p.103-115(2008) ; (JAEA-J 03948)

We carried out a detailed measurement of neutron induced α-particle emission double-differential cross-section of carbon at 14.2 MeV, for which there were few measured data in spite of its importance in many applications. The obtained cross-section for the ¹²C(n,α₀)⁹Be_{(ground state)} reaction agreed well with previous experiments and evaluated nuclear data. The obtained angular-differential cross-section of the ¹²C(n,n'+3α) reaction for α-particles showed a strong forward-peaked distribution that suggested significant contribution of the direct reaction process to the 3α breakup. We attempted to calculate the emitted particle spectra by means of a Monte Carlo method and estimate the branching ratio of the channels which contribute to the ¹²C(n,n'+3α) reaction. As a result, it was found that the ¹²C(n,α)⁹Be* channels play an important role in generating the experimental double-differential cross-section both of emitted α-particles and neutrons. The estimated ratio of the ¹²C(n,α)⁹Be* channels was around 40 %, somewhat larger than those evaluated in previous studies.

36000684
Development of irradiation capsules in liquid metal environment in Joyo and their application to irradiation creep measurement of vanadium alloys
Fukumoto, Kenichi*; Narui, Minoru*; Matsui, Hideki*; Ito, Kazuhiro; Yano, Yasuhide
Journal of Nuclear Science and Technology 45(2), p.171-178(2008) ; (JAEA-J 03949)

In order to perform irradiation experiments under liquid metal environment in a nuclear reactor, an irradiation technique with sodium bonding irradiation capsules has been developed and a series of neutron irradiation experiments with sodium bonding irradiation capsule were performed in Joyo. The design and fabrication of sodium bonding capsule, sodium filling into capsules, capsule loading to Joyo, irradiation experiments, dismantling for irradiated capsule, removing the irradiated specimens from sodium filled capsules, and sodium cleaning the irradiated specimens were established through this study. Using the Joyo irradiation with the sodium bonding capsules where irradiation temperature was distributed uniformly, the irradiation creep experiment for highly purified V-4Cr-4Ti alloys, NIFS-Heat was carried out and the knowledge about the irradiation creep behavior of the alloys was obtained.

36000685
Sorption of U(VI) on the 4-mercaptopyridine self-assembled monolayer
Nankawa, Takuya; Suzuki, Yoshinori; Ozaki, Takuo; Francis, A. J.; Onuki, Toshihiko
Journal of Nuclear Science and Technology 45(3), p.251-256(2008) ; (JAEA-J 03950)

Sorption of U(VI) on the 4-mercaptopyridine self-assembled-monolayer (4-PyS-SAM) on Au(111) was studied by cyclic voltammetry. Cyclic voltammograms (CV) of the 4-PyS-SAM working electrode was obtained by contact with 1 mM UO₂(NO₃)₂ solution, 1 mM UO₂(NO₃)₂ and 50 mM acetic acid solution, or 1 mM UO₂(NO₃)₂ and 50 mM oxalic acid solution for 6 h at pH 4. Reduction current of uranium(VI) to U(V) was detected in the CV. The CV of the U(VI) associated 4-PyS-SAM after transporting to U(VI) free 0.1 M NaClO4 solution showed that the reduction current was detected in the cases of UO₂(NO₃)₂ and U(VI)-acetate, but not in the case of U(VI)-oxalate solutions, indicating that U(VI) was adsorbed on the 4-PyS-SAM from the UO₂(NO₃)₂ and U(VI)-acetate solutions, but not from U(VI)-oxalate solution. These results suggests that stability of U(VI)-4-PyS-SAM is not so high that U(VI)-4-PyS-SAM cannot be formed in the presence of 50 mM oxalate.

36000686
Development of a performance analysis code for vibro-packed MOX fuels
Ishii, Tetsuya; Nemoto, Junichi*; Asaga, Takeo; Sato, Seichi*; Mayorshin, A.*; Shishalov, O.*; Kryukov, F.*
Journal of Nuclear Science and Technology 45(4), p.263-273(2008) ; (JAEA-J 03951)

In order to develop a vibro-packed MOX fuel performance analysis code, thermochemical and mechanical properties of the vibro-packed fuels were incorporated into a pellet type fuel performance analysis code CEDAR. Calculations were made by the developed code on a vibro-packed MOX fuel pin irradiated at BN-600 in Russia. Since the calculated results agreed well with the behaviors obtained from the experimental data, it can be concluded that the code was well modeled and qualitatively validated.

36000687
Prediction accuracy improvement of neutronic characteristics of a breeding light water reactor core by extended bias factor methods with use of FCA-XXII-1 critical experiments
Kugo, Teruhiko; Ando, Masaki; Kojima, Kensuke; Fukushima, Masahiro; Mori, Takamasa; Nakano, Yoshihiro; Okajima, Shigeaki; Kitada, Takanori*; Takeda, Toshikazu*
Journal of Nuclear Science and Technology 45(4), p.288-303(2008) ; (JAEA-J 03952)

The effectiveness of the extended bias factor methods, the LC and PE methods, is numerically investigated by applying them to a breeding light water reactor core as a target core with use of FCA-XXII-1 critical experiments. The present study numerically verifies the features of the extended bias factor methods. Both the methods can improve the prediction accuracy the most by using all the experiments. The PE method always improves the prediction accuracy with any combination of experiments. The PE method is always superior to the LC method for improvement of the prediction accuracy. From the present study, the followings are found. The experiments on multiplication factor are more applicable to a reaction rate ratio of ²³⁸U capture to ²³⁹Pu fission (C28/F49) of the target core than the experiments on C28/F49. Combinations of the experiments on multiplication factor is more effective to a void reactivity of the target core than those of the experiments on void reactivity though those on void reactivity are superior to those on multiplication factors in the case of using a single experiment. From these results, we conclude that the experiments on multiplication factor are more effective than the other experiments for all the neutronic characteristics of the target core. From these results, it is concluded that the PE method is promising to complement full mockup experiments for various future nuclear systems by using a number of existing and future benchmark experiments.

36000688
Existence and origin of compensation layer thickness in Tb₂₀Co₈₀/Pd multilayered films
Tanaka, Masahito*; Asahi, Toru*; Agui, Akane; Mizumaki, Masaichiro*; Sayama, Junichi*; Osaka, Tetsuya*
Journal of Physics D; Applied Physics 41(5), p.055003_1-055003_4(2008) ; (JAEA-J 03955)

36000689
Field-induced incommensurate order in frustrated spin ladder
Sakai, Toru; Okamoto, Kiyomi*
Journal of Physics; Condensed Matter 19(14), p.145231_1-145231_5(2007) ; (JAEA-J 03956)

The S=1/2 frustrated spin ladder is investigated by the numerical exact diagonalization and the finite-size scaling. It is found that if the frustration is strong enough, a possible new phase with an incommensurate long-range order would appear in magnetic field.

36000690
Structural and electronic properties of liquid InAs under pressure
Shimojo, Fuyuki*; Miyata, Yasuhisa*; Sugahara, Takayuki*; Hattori, Takanori; Tsuji, Kazuhiko*
Journal of Physics; Conference Series 98, p.042016_1-042016_4(2008) ; (JAEA-J 03958)

The structural and bonding properties of liquid InAs under pressure are investigated by ab initio molecular-dynamics simulations. The calculated structure factors are in good agreement with the recent X-ray diffraction measurements over a wide range of pressure. It is shown that the pressure dependence of the spatial correlation between atoms depends on the species of atomic pairs reflecting the strength of the covalent bonding. A detailed investigation of the pair distribution functions confirms that different pressure-induced structural changes occur below and above 6-10 GPa. It is suggested that such structural changes are related to the reduction of the covalent nature under pressure.

36000691
Chemical-state-selective observations on Si-SiO_x at nanometer scale by photoelectron emission microscopy combined with synchrotron radiation
Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Honda, Mitsunori; Hirao, Norie*; Deng, J.; Narita, Ayumi
Journal of Physics; Conference Series 100, p.012015_1-012015_4(2008) ; (JAEA-J 03959)

Chemical-state-selective mapping of micro-patterns for silicon compounds has been demonstrated using photoelectron emission microscopy excited by soft X-rays from synchrotron light source. The samples investigated were micro-patterns of silicon oxides, silicon nitrides, and organic silicon compounds. By scanning the X-ray energy around the Si K-edge, we succeeded in observing the sub-micron images depending on the valence states. When we annealed the sample, the lateral diffusion was observed from 700 degree Celsius. During the annealing, however, no intermediate valence states were observed at the Si-SiO₂ interfaces. It was elucidated that the diffusion of oxygen induced the sudden changes of the Si valence states from Si⁰ to Si⁴⁺ without any intermediate valence states. The results for the chemical-state-selective mappings and lateral diffusions are also presented for organic silicon compounds.

36000692
Reduction of hydrogen content in pure Ti
Ogiwara, Norio; Suganuma, Kazuaki; Hikichi, Yusuke; Kamiya, Junichiro; Kinsho, Michikazu; Sukenobu, Satoru*
Journal of Physics; Conference Series 100, p.092024_1-092024_5(2008) ; (JAEA-J 03960)

Pure Ti is adopted as a material for ducts and bellows at the 3 GeV-RCS in J-PARC project, because of its small residual radioactivity. In the particle accelerator, the H₂ outgassing due to ion impact is often dominant gas release. As the reduction of hydrogen content probably leads to the suppression of ion induced desorption, we intend to reduce the hydrogen content in the Ti by in-situ vacuum baking. First of all, thermal desorption behavior and the change in hydrogen content have been investigated. The vacuum firing over than 550°C is effective to reduce the hydrogen content in the Ti. The mechanical properties have been also monitored because a grain growth leads to the decrease of mechanical strength. Even after the treatment at 750°C for 12 h the decreases in tensile and yield strength are so small (∼10%) that we have no anxiety about the reduction of mechanical strength. Based upon this study, the vacuum firing has been applied for the RCS machine.

36000693
Numerical investigation of cross flow phenomena in a tight-lattice rod bundle using advanced interface tracking method
Zhang, W.; Yoshida, Hiroyuki; Ose, Yasuo*; Onuki, Akira; Akimoto, Hajime; Hotta, Akitoshi*; Fujimura, Ken*
Journal of Power and Energy Systems (Internet) 2(2), p.456-466(2008) ; (JAEA-J 03961)

In relation to the design of an innovative FLexible-fuel-cycle Water Reactor (FLWR), investigation of thermal-hydraulic performance in tight-lattice rod bundles of the FLWR is being carried out at Japan Atomic Energy Agency (JAEA). The FLWR core adopts a tight triangular lattice arrangement with about 1 mm gap clearance between adjacent fuel rods. In view of importance of accurate prediction of cross flow between subchannels in the evaluation of the boiling transition (BT) in the FLWR core, this study presents a statistical evaluation of numerical simulation results obtained by a detailed two-phase flow simulation code, TPFIT, which employs an advanced interface tracking method. In order to clarify mechanisms of cross flow in such tight lattice rod bundles, the TPFIT is applied to simulate water-steam two-phase flow in two modeled subchannels. Attention is focused on instantaneous fluctuation characteristics of cross flow. With the calculation of correlation coefficients between differential pressure and gas/liquid mixing coefficients, time scales of cross flow are evaluated, and effects of mixing section length, flow pattern and gap spacing on correlation coefficients are investigated. Differences in mechanism between gas and liquid cross flows are pointed out.

36000694
Development of fast reactor structural integrity monitoring technology using optical fiber sensors
Matsuba, Kenichi; Ito, Chikara; Kawahara, Hirotaka; Aoyama, Takafumi
Journal of Power and Energy Systems (Internet) 2(2), p.545-556(2008) ; (JAEA-J 03962)

Significant thermal stresses are loaded onto the structures of sodium-cooled fast reactor (SFR) due to high temperature and large temperature gradients associated with employing sodium coolant with its high thermal conductivity and low heat capacity. Therefore, it is important to monitor the temperature variation, related stress and displacement, and vibration in the cooling system piping and components in order to assure structural integrity while the reactor plant is in-service. SFR structural integrity monitoring can be enhanced by an optical fiber sensor, which is capable of continuous or dispersed distribution measurements of various properties such as radiation dose, temperature, strain, displacement and acceleration. In the experimental fast reactor Joyo, displacement and vibration measurements of the primary cooling system have been carried out using Fiber Bragg Grating (FBG) sensors to evaluate the durability and measurement accuracy of FBG sensors in a high γ-ray environment. The data were successfully obtained with no significant signal loss up to an accumulated γ-ray dose of approximately 4×10⁴ Gy corresponding to 120 EFPDs operation. Measured displacement of the piping support was nearly equal to the calculated thermal displacement. Measured vibration power spectra of the piping support were similar to those measured with a reference acceleration sensor. The measured results indicate that the FBG sensor is suitable for monitoring the displacement and vibration aspects of fast reactor cooling system integrity in a high γ-ray environment.

36000695
Experimental method of in-pile creep rupture behavior of ODS cladding materials in the experimental fast reactor Joyo
Ito, Chikara; Kagota, Eiichi; Aoyama, Takafumi
Journal of Power and Energy Systems (Internet) 2(2), p.620-632(2008) ; (JAEA-J 03963)

An in-pile creep rupture experiment was conducted in the experimental fast reactor Joyo to evaluate the creep rupture strength of oxide dispersion strengthened (ODS) ferritic steel under neutron irradiation. ODS has been developed as a most promising fuel cladding material for the next generation fast reactor because of its high temperature resistance and low swelling properties. The irradiation test device MAterial testing RIg with temperature COntrol (MARICO) was developed for the in-pile experiment in Joyo with a temperature control precision of ±4°C. Twenty four ODS specimens with no fuel were pressurized by helium gas up to 22 MPa to accelerate the creep rupture testing. The specimen temperature in the MARICO is controlled by changing the ratio of argon and helium fill gases, which changes the gas gap thermal conductivity between the double walled capsule containing the specimen. The experiment has been carried out in the Joyo MK-III core from April 2006 and will continue until May 2007. Each creep rupture event was successfully detected by the temperature change at the exit of the capsule and by γ-ray spectrometry of the reactor cover gas when the filled gas was released from the specimen. The specimen was then identified by analyzing the tag gas isotopic ratio using laser resonance ionization mass spectrometry (RIMS).

36000696
Irradiation test of fuel containing minor actinides in the experimental fast reactor Joyo
Soga, Tomonori; Sekine, Takashi; Tanaka, Kosuke; Kitamura, Ryoichi; Aoyama, Takafumi
Journal of Power and Energy Systems (Internet) 2(2), p.692-702(2008) ; (JAEA-J 03964)

The mixed oxide containing minor actinides (MA-MOX) fuel irradiation program is being conducted using Joyo. Two irradiation experiments were conducted in the MK-III 3rd operational cycle. Six prepared fuel pins included MOX fuel containing americium, MOX fuel containing americium and neptunium, and reference MOX fuel. The first test was conducted with high linear heat rates of 430 W/cm maintained during only 10 minutes in order to confirm whether or not fuel melting occurred. After 10 minutes irradiation in May 2006, the test subassembly was transferred to the hot cell facility and two test pins were replaced with dummy pins. The test subassembly loaded with the remaining four fuel pins was re-irradiated in Joyo for 24 hours in August 2006 to obtain re-distribution data on MA-MOX fuel. Linear heat rates for each pin were calculated using MCNP. Post irradiation examination of these pins to confirm the irradiation behavior of MA-MOX fuel is underway.

36000697
Core dynamics analysis for reactivity insertion and loss of coolant flow tests using the high temperature engineering test reactor
Takamatsu, Kuniyoshi; Nakagawa, Shigeaki; Takeda, Tetsuaki
Journal of Power and Energy Systems (Internet) 2(2), p.790-803(2008) ; (JAEA-J 03965)

The reactivity insertion test simulates the rapid increase in the reactor power by withdrawing the control rod without operating the reactor power control system. In addition, the loss of coolant flow tests has been conducted to simulate the rapid decrease in the reactor power by tripping one, two or all out of three gas circulators. The experimental results have revealed the inherent safety features of HTGRs, such as the negative reactivity feedback effect. The numerical analysis code, which was named ACCORD, was developed to analyze the reactor dynamics including the flow behavior in the HTTR core. We have modified this code to use a model with four parallel channels and twenty temperature coefficients. Furthermore, we added another analytical model of the core for calculating the heat conduction between the fuel channels and the core in the case of the loss of coolant flow tests. This paper describes the effect of the model is formulated quantitatively with our proposed equation.

36000698
Characterization of homoionic Fe²⁺-type montmorillonite; Potential chemical species of iron contaminant
Kozai, Naofumi; Inada, Koichi*; Adachi, Yoshifusa*; Kawamura, Sachi*; Kashimoto, Yusuke*; Kozaki, Tamotsu*; Sato, Seichi*; Onuki, Toshihiko; Sakai, Takuro; Sato, Takahiro; Oikawa, Masakazu*; Esaka, Fumitaka; Mitamura, Hisayoshi
Journal of Solid State Chemistry 180(8), p.2279-2289(2007) ; (JAEA-J 03966)

Fe²⁺-montmorillonite with Fe²⁺ ions occupying cation exchange sites is an ideal transformation product in bentonite buffer material. We previously prepared a Fe²⁺-montmorillonite sample using a FeCl₂ solution under an inert gas condition. This study attempted to determine the potential contaminant iron chemical species in the sample. It was found that a small amount of Cl^- ions remained dispersed throughout the sample. The Cl^- ion retention may be due to the adsorption of FeCl⁺ in the initial FeCl₂ solution and the subsequent containment of the Cl^- ions that are dissociated from the FeCl⁺ during excess salt removal treatment. The latter may be explained by the slow release of the remaining Cl^- ions from the collapsed interlayer of the montmorillonite or the transformation of a minor fraction of the remaining FeCl⁺ to iron (III) hydroxide chloride complexes having low solubility.

36000699
Synthesis and characterization of bulky mesoporous silica Pd-MCM-41
Nagata, Hidezumi*; Hirao, Norie*; Onoki, Takamasa*; Baba, Yuji; Yamasaki, Yuki*; Nakahira, Atsushi*
Journal of the Ceramic Society of Japan 116(1350), p.216-219(2008) ; (JAEA-J 03967)

Bulky palladium catalyst supported on mesoporous silica (Pd-MCM-41) was successfully synthesized by hydrothermal hot-pressing method. The structure of the palladium species in Pd-MCM-41 bulk before and after heat-treatment process was investigated by X-ray diffraction (XRD), X-ray absorption near edge structure (XANES) and transmission electron microscopy (TEM). On the basis of these results, the microstructures and mesoporous properties of Pd-MCM-41 were discussed. As a result, it was revealed that the obtained Pd-MCM-41 bulks possessed a high area of over 1000 m²/g and the electronic state of palladium in Pd-MCM-41 bulk is almost equal to palladium (0) metal.

36000700
Magnetic and superconducting properties of LaIrSi₃ and CeIrSi₃ with the non-centrosymmetric crystal structure
Okuda, Yusuke*; Miyauchi, Yuichiro*; Ida, Yuki*; Takeda, Yuji*; Tonohiro, Chie*; Ozuchi, Yasuhiro*; Yamada, Tsutomu*; Nguyen, D.; Matsuda, Tatsuma; Haga, Yoshinori; Takeuchi, Tetsuya*; Hagiwara, Masayuki*; Kindo, Koichi*; Harima, Hisatomo*; Sugiyama, Kiyohiro*; Settai, Rikio*; Onuki, Yoshichika*
Journal of the Physical Society of Japan 76(4), p.044708_1-044708_11(2007) ; (JAEA-J 03971)

Single crystals of LaIrSi₃ and CeIrSi₃ were grown by the Czochralski pulling method in a tetra-arc furnace and the magnetic and superconducting properties, together with super- conductivity in CeIr_1-xCo_xSi₃, were clarified by measuring the electrical resistivity, specific heat, magnetic susceptibility, magnetization and de Haas-van Alphen (dHvA) effect. From the results of the dHvA experiment for LaIrSi₃, the Fermi surface is found to split into two Fermi surfaces due to the spin-orbit interaction arising from the non-centrosymmetric crystal structure. The electronic state of CeIrSi₃ is tuned from the antiferro- magnetic state to the superconducting state by applying pressure. The upper critical field H_c2(0) at a pressure of 2.65 GPa is found to be highly anisotropic. Large magnitude and anisotropy of H_c2(0) in CeIrSi₃ are consistent with the theoretical prediction for superconductivity in the non-centrosymmetric crystal structure.

36000701
Magnetic properties and crystalline electric field scheme in RRhIn₅ (R: Rare earth)
Hieu, N. V.*; Takeuchi, Tetsuya*; Shishido, Hiroaki*; Tonohiro, Chie*; Yamada, Tsutomu*; Nakashima, Hiroshi*; Sugiyama, Kiyohiro*; Settai, Rikio*; Matsuda, Tatsuma; Haga, Yoshinori; Hagiwara, Masayuki*; Kindo, Koichi*; Araki, Shingo*; Nozue, Yasuo*; Onuki, Yoshichika
Journal of the Physical Society of Japan 76(6), p.064702_1-064702_16(2007) ; (JAEA-J 03972)

A seriese of ternary compounds RRhIn₅ (R: rare earth) has been grown in the single crystalline form by means of the flux method. Most of these compounds order antiferromagnetically at low temperatures, except R = Y, La, Pr and Yb. The magnetic properties are discussed on the basis of the crystalline-field parameters.

36000702
Single-component molecular metals as multiband π-d systems
Seo, Hitoshi; Ishibashi, Shoji*; Okano, Yoshinori*; Kobayashi, Hayao*; Kobayashi, Akiko*; Fukuyama, Hidetoshi*; Terakura, Kiyoyuki*
Journal of the Physical Society of Japan 77(2), p.023714_1-023714_4(2008) ; (JAEA-J 03973)

Electronic states of single-component molecular metals M(tmdt)₂ (M=Ni,Au) are studied theoretically. We construct an effective three-band Hubbard model for each material by numerical fitting to first-principles band calculations, while referring to molecular orbital calculations for the isolated molecules. The model consists of two kinds of base orbital for each molecule with hybridization between them, i.e., a π-character orbital for each of the two tmdt ligands, and, a pdπ-orbital for M=Ni or a pdσ-orbital for M=Au centered on the metal site; this indicates that these materials can be considered as novel multiband π-d systems. We find that both orbitals contribute to realize the metallic character in Ni(tmdt)₂. The origin of the antiferromagnetic transition observed in Au(tmdt)₂ is also discussed based on this model.

36000703
Single crystal growth and the fermi surface property in LuCoGa₅
Matsuda, Tatsuma; Haga, Yoshinori; Sakai, Hironori; Aoki, Dai*; Ikeda, Shugo; Yamamoto, Etsuji; Shishido, Hiroaki*; Settai, Rikio*; Harima, Hisatomo*; Onuki, Yoshichika
Journal of the Physical Society of Japan 77(2), p.024704_1-024704_6(2008) ; (JAEA-J 03974)

We succeeded in growing a high-quality single crystal of LuCoGa₅ with the HoCoGa₅-type tetragonal crystal structure by the Ga self-flux method. The lattice parameters, fractional coordinates, and thermal parameters were determined from single-crystal X-ray diffraction measurements. We also measured the electrical resistivity, specific heat, and the de Haas-van Alphen (dHvA) effect. The Fermi surface mainly consists of two nearly cylindrical Fermi surfaces, which are well explained by the results of full-potential linearized augmented plane wave (FLAPW) energy band calculations.

36000704
Soft X-ray magnetic circular dichroism study of uranium monochalcogenides at uranium N_4,5 absorption edges
Okane, Tetsuo; Takeda, Yukiharu; Okamoto, Jun*; Mamiya, Kazutoshi*; Okochi, Takuo; Fujimori, Shinichi; Saito, Yuji; Yamagami, Hiroshi; Fujimori, Atsushi; Ochiai, Akira*; Tanaka, Arata*
Journal of the Physical Society of Japan 77(2), p.024706_1-024706_6(2008) ; (JAEA-J 03975)

X-ray magnetic circular dichroism (XMCD) was measured for the ferromagnetic uranium monochalcogenides US and USe at U N_4,5 absorption edges in the soft X-ray region. The obtained N_4,5 XMCD signal of US was comparable to the M_4,5 XMCD signal obtained in previous studies. From the sum-rule analysis of XMCD data, it was shown that the estimated ratios of orbital magnetic moment to spin magnetic moment were almost the same for US and USe. The analysis of the XAS branching ratio indicated an increase in 5f electron occupation number from US to USe.

36000705
Cylindrical domains of block copolymers developed via ordering under moving temperature gradient
Mita, Kazuki*; Tanaka, Hirokazu*; Saijo, Kenji*; Takenaka, Mikihito*; Hashimoto, Takeji
Macromolecules 40(16), p.5923-5933(2007) ; (JAEA-J 03976)

A zone heating method, which imposes the moving temperature-gradient field on order in process of various melts in general, enabled to control a macroscopic orientation of microdomain structures in block copolymer bulk. We applied the method to a polystyrene-block-polyisoprene diblock copolymer forming hexagonally packed cylindrical domains (hex-cyl) in the absence of extermal fields. We discovered that the method creates the following special texture of hex-cyl; (1) The texture seemingly consists of volume-filled columnar grains with the grain axis parallel to the temperature gradient axis (defined as the oz axis). (2) The cylinder axis always orients perpendicular to the oz axis with a rotational angle φ of the cylinder axis around the oz axis being fixed within a grain.

36000706
Control of self-assembling processes of polyamidoamine dendrimers and Pd nanoparticles
Tanaka, Hirokazu*; Hashimoto, Takeji; Koizumi, Satoshi; Ito, Hideaki*; Naka, Kensuke*; Chujo, Yoshiki*
Macromolecules 41(5), p.1815-1824(2008) ; (JAEA-J 03977)

We have investigated the self-assembly formed by palladium acetate (Pd(OAc)₂) and polyamidoamine dendrimers (GN-NH₂) in a mixed solvent of methanol and N, N-dimethylformamide. We aim to explore effects of the generation number (GN) and concentration of the dendrimers, [GN-NH₂], on the self-assembly of the dendrimers (defined hereafter as "templates") and the Pd nanoparticles inside the templates in order to clarify physical factors controlling the self-assembling mechanisms. We found that the templates are formed only when [GN-NH₂] falls below a critical value and thereby a sufficient amount of Pd(OAc)₂ exists as the binders between the dendrimers. Otherwise dendrimers are molecularly dispersed in solution.

36000707
Temporally distinct response of irradiated normal human fibroblasts and their bystander cells to energetic heavy ions
Hamada, Nobuyuki*; Ni, M.*; Funayama, Tomoo; Sakashita, Tetsuya; Kobayashi, Yasuhiko
Mutation Research; Fundamental and Molecular Mechanisms of Mutagenesis 639(1-2), p.35-44(2008) ; (JAEA-J 03978)

To characterize the energetic heavy ion-induced bystander response, we employed precise microbeams of C and Ne ions for targeting only a very small fraction of cells in confluent fibroblast cultures. Conventional broad field irradiation was conducted in parallel to see the effects in irradiated cells. Exposure of 0.00026% of cells led to nearly 10% reductions in the clonogenic survival and twofold rises in the apoptotic incidence regardless of ion species. Whilst apoptotic frequency increased with time up to 72 h post irradiation in irradiated cells, its frequency escalated up to 24 h post irradiation but declined at 48 h post irradiation in bystander cells, indicating that bystander cells exhibit transient commitment to apoptosis. C and Ne-ion microbeam irradiation similarly caused almost twofold increments in the levels of serine 15-phosphorylated p53 proteins, irrespective of whether 0.00026, 0.0013 or 0.0066% of cells were targeted. Whereas the levels of phosphorylated p53 were elevated and remained unchanged at 2 and 6 h post irradiation in irradiated cells, its levels rose at 6 h post irradiation but not at 2 h post irradiation in bystander cells, suggesting that bystander cells manifest delayed p53 phosphorylation.

36000708
Itinerant to localized transition of f electrons in the antiferromagnetic superconductor UPd₂Al₃
Fujimori, Shinichi; Saito, Yuji; Okane, Tetsuo; Fujimori, Atsushi*; Yamagami, Hiroshi*; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika*
Nature Physics 3(9), p.618-622(2007) ; (JAEA-J 03979)

In heavy Fermion (HF) compounds, f electrons show both itinerant and localized behaviour depending on temperature. Above the characteristic temperature T^*, their magnetic properties are well described by the completely "localized" f-electron models. On the other hand, well below T^*, their Fermi surfaces (FS's) have been explained well by the "itinerant" f-electron model. These two models assume totally different natures of f-electrons, and how they transform between these states as a function of temperatures has never been understood on the level of their electronic structures. Here we have studied the band structure of the HF antiferromagnetic superconductor UPd₂Al₃ well below and above T^* by angle-resolved photoelectron spectroscopy (ARPES), and have found that the f-bands, which form the FS's at low temperatures, are excluded from FS's at high temperatures.

36000709
Quasiparticle interference and superconducting gap in Ca_2-xNa_xCuO₂Cl₂
Hanaguri, Tetsuo*; Kosaka, Yuki*; Davis, J. C.*; Lupien, C.*; Yamada, Ikuya*; Azuma, Masaki*; Takano, Mikio*; Oishi, Kazuki; Ono, Masaki*; Takagi, Hidenori*
Nature Physics 3(12), p.865-871(2007) ; (JAEA-J 03980)

High-transition-temperature (high-T_c) superconductivity is ubiquitous in the cuprates containing CuO₂ planes, but each cuprate has its own character. The study of the material dependence of the d-wave superconducting gap (SG) should provide important insights into the mechanism of high-T_c superconductivity. However, because of the "pseudogap" phenomenon, it is often unclear whether the energy gaps observed by spectroscopic techniques really represent the SG. Here, we use scanning tunnelling spectroscopy to image nearly optimally doped Ca_2-xNa_xCuO₂Cl₂ (Na-CCOC) with T_c=25 ∼ 28 K. It enables us to observe the quasiparticle interference effect in this material, through which we obtain unambiguous information on the SG. Our analysis of quasiparticle interference in Na-CCOC reveals that the SG dispersion near the gap node is almost identical to that of Bi₂Sr₂CaCu₂O_y (Bi2212) at the same doping level, despite the T_c of Bi2212 being three times higher than that of Na-CCOC. We also find that the SG in Na-CCOC is confined in narrower energy and momentum ranges than Bi2212, which explains - at least in part - the remarkable material dependence of T_c.

36000710
Effect of toroidal field ripple on plasma rotation in JET
de Vries, P. C.*; Salmi, A.*; Parail, V.*; Giroud, C.*; Andrew, Y.*; Biewer, T. M.*; Crombé, K.*; Jenkins, I.*; Johnson, T.*; Kiptily, V.*; Loarte, A.*; Lönnroth, J.*; Meigs, A.*; Oyama, Naoyuki; Sartori, R.*; Saibene, G.*; Urano, Hajime; Zastrow, K.-D.*; JET-EFDA Contributors
Nuclear Fusion 48(3), p.035007_1-035007_6(2008) ; (JAEA-J 03981)

Dedicated experiments on TF ripple effects on the performance of tokamak plasmas have been carried out at JET. The TF ripple was found to have a profound effect on the plasma rotation. The central Mach number, M, defined as the ratio of the rotation velocity and the thermal velocity, was found to drop as a function of TF ripple amplitude from an average value of M = 0.40-0.55 for operations at the standard JET ripple of 0.08% to M = 0.25-0.40 for 0.5% ripple and M = 0.1-0.3 for 1% ripple. With standard co-current injection of neutral beam injection (NBI), plasmas were found to rotate in the co-current direction. However, for higher TF ripple amplitudes (∼1%) an area of counter rotation developed at the edge of the plasma, while the core kept its co-rotation.

36000711
Recovery of U-Pu alloy from MOX using a pyroprocess series
Kitawaki, Shinichi; Shinozaki, Tadahiro; Fukushima, Mineo; Usami, Tsuyoshi*; Yahagi, Noboru*; Kurata, Masaki*
Nuclear Technology 162(2), p.118-123(2008) ; (JAEA-J 03983)

A series test of pyro-process was carried out to recover U-Pu alloy from MONJU MOX pellets. In the Li-reduction step, the reduction behavior of MOX was similar to that of UO₂. In the electrorefining step, the separation factor between U and Pu was 5.7 for the combination of reduced MOX anode and liquid cadmium cathode, which is almost comparable to the value in the previous studies. For the material balance, approximately 98% of U and 103% of Pu were detected in the electrodes or molten salt after the electrolysis with respect to the initial amounts in the anode or molten salt. Considering the analytical error of ICP-AES, these values are reasonable. The remained amount of U in the anode was slightly larger than that of Pu due to the re-oxidation. The U-Pu alloy ingot was successfully formed by distillation of Cd.

36000712
Cyclic voltammetry behavior of americium at a liquid cadmium electrode in LiCl-KCl eutectic melts
Hayashi, Hirokazu; Akabori, Mitsuo; Minato, Kazuo
Nuclear Technology 162(2), p.129-134(2008) ; (JAEA-J 03984)

The electrode reactions of americium at a liquid cadmium electrode were investigated by cyclic voltammetry (CV) of AmCl₃-(LiCl-KCl)_eut. at both 723K and 773K in comparison with those at a molybdenum electrode. The redox peaks assigned to Am(III)/Am(0) (in Cd) were observed with the liquid Cd electrode while the redox reactions of Am(III)/Am(II) and Am(II)/Am(0) were observed with the Mo electrode. The formal standard potential of Am(III)/Am(0) obtained with the liquid Cd electrode is more positive than those calculated for the Mo electrode at both 723K and 773K. The potential shifts were attributed to the lowering of the activity of Am by the formation of the intermetallic compound at the interface between Cd and the molten salt. The Gibbs free energies of formation of the Am-Cd intermetallic compound, which could be AmCd₆, are estimated to be -119 and -113 kJ/mol at 723K and 773K, respectively.

36000713
Influence of self-irradiation on the magnitude of the superfluid density in PuCoGa₅ probed by muon spin rotation
Oishi, Kazuki; Heffner, R. H.; Ito, Takashi; Higemoto, Wataru; Morris, G. D.*; Bauer, E. D.*; Graf, M. J.*; Zhu, J.-X.*; Morales, L. A.*; Sarrao, J. L.*; Fluss, M. J.*; MacLaughlin, D. E.*; Shu, L.*
Physica B; Condensed Matter 403(5-9), p.1013-1014(2008) ; (JAEA-J 03985)

PuCoGa₅ has attracted much interest because it is the first Pu-based superconductor, having an order of magnitude higher transition temperature T_c=18.5K than the isostructural heavy fermion superconductor CeCoIn₅ (T_c=2.3K). The mechanism of the superconductivity in PuCoGa₅ is still under investigation, though recent experiments and theory suggest a magnetic origin. A unique aspect of this compound is the self-irradiation damage because Pu (²³⁹Pu, T^1/2 = 24,000 years) creates lattice defects which scatter electrons and, hence, break superconducting pairs. In order to elucidate the magnitude and temperature dependence of the magnetic penetration depth λ, we have performed μSR measurements in the same PuCoGa₅ single crystals after 25 and 400 days of aging. We found that T_c decreased from 18.5K to 15K for the aged sample, yet a quasi-linear temperature dependence was found for the low-temperature λ(T) in both the fresh and aged sample, consistent with d-wave pairing symmetry. The magnitude of the muon spin relaxation rate σ in the aged sample, σ∝ 1/λ²∝ρ_s/m^*, where ρ_s and m^* are the superfluid density and the effective mass, respectively, is reduced by about 70% compared to fresh sample. This indicates that the scattering from self-irradiation induced defects is not in the limit of the conventional Abrikosov-Gor'kov pair-breaking theory, but rather in the limit of short coherence length (about 2nm in PuCoGa₅) superconductivity.

36000714
First-principles electron dynamics simulation for optical breakdown of dielectrics under an intense laser field
Otobe, Tomohito; Yamagiwa, Mitsuru; Iwata, Junichi*; Yabana, Kazuhiro*; Nakatsukasa, Takashi*; Bertsch, G. F.*
Physical Review B 77(16), p.165104_1-165104_5(2008) ; (JAEA-J 03988)

We present a first-principle calculation for optical dielectric breakdown induced by an intense laser field. We employ the time-dependent density-functional theory, solving the time-dependent Kohn-Sham equation in real time and real space. The calculation shows a qualitative change of electron dynamics as the laser intensity increase, above 7×10¹⁴ W/cm². Following the pulse, the excited electron exhibit a coherent plasma oscillation.

36000715
Z dependence of the N = 152 deformed shell gap; In-beam γ-ray spectroscopy of neutron-rich ^{245, 246}Pu
Makii, Hiroyuki; Ishii, Tetsuro; Asai, Masato; Tsukada, Kazuaki; Toyoshima, Atsushi; Matsuda, Makoto; Makishima, Akiyasu*; Kaneko, Junichi*; Tome, Hayato*; Ichikawa, Shinichi; Shigematsu, Soichiro*; Kono, Toshiyuki*; Ogawa, Masao*
Physical Review C 76(6), p.061301_1-061301_5(2007) ; (JAEA-J 03994)

We have measured deexcitation γ rays for the first time in the neutron-rich nuclei of ²⁴⁶Pu₁₅₂ and ²⁴⁵Pu₁₅₁ produced by the (¹⁸O, ¹⁶O) and the (¹⁸O, ¹⁷O) reactions, respectively. The ground-state band of ²⁴⁶Pu was established up to 12⁺ states. The systematics of the moments of inertia of ₉₄Pu isotopes suggests that the N = 152 deformed subshell closure disappears in these isotopes. The measurements of deexcitation γ rays in ²⁴⁵Pu shows a small energy spacing between neutron orbitals at N = 152, which explans the disappearance of the subshell closure.

36000716
Origin of spin-orbit splitting for monolayers of Au and Ag on W(110) and Mo(110)
Shikin, A. M.*; Varykhalov, A.*; Prudnikova, G. V.*; Usachov, D.*; Adamchuk, V. K.*; Yamada, Yoichi; Riley, J. D.*; Rader, O.*
Physical Review Letters 100(5), p.057601_1-057601_4(2008) ; (JAEA-J 03996)

Spin-orbit coupling can give rise to spin-split electronic states without a ferromagnet or an external magnetic field. We create large spin-orbit splittings in a Au and Ag monolayer on W(110) and show that the size of the splitting does not depend on the atomic number of the Au or Ag overlayer but of the Wsubstrate. Spin- and angle-resolved photoemission and Fermi-surface scans reveal that the overlayer statesacquire spin polarization through spin-dependent overlayer-substrate hybridization.

36000717
Role of pressure gradient on Intrinsic toroidal rotation in tokamak plasmas
Yoshida, Maiko; Kamada, Yutaka; Takenaga, Hidenobu; Sakamoto, Yoshiteru; Urano, Hajime; Oyama, Naoyuki; Matsunaga, Go; JT-60 Team
Physical Review Letters 100(10), p.105002_1-105002_4(2008) ; (JAEA-J 03997)

Non-diffusive terms of toroidal momentum transport are observed in JT-60U tokamak plasmas. The characteristic of driving source of plasma toroidal rotation driven by the pressure gradient is found using transient momentum transport analysis. The difference between the measured toroidal rotation velocity (Vt) profile and the reproduced one using momentum transport coefficients is observed in high pressure plasmas. This difference can be explained by the effect of the spontaneous rotation driven by the pressure gradient. In addition, a structural correlation between the non-diffusive inward flux and the radial shear of the toroidal rotation velocity (-dVt/dr) has been found, and the non-diffusive inward flux increases with increasing -dVt/dr.

36000718
Observation of the 3n evaporation channel in the complete hot-fusion reaction ²⁶Mg + ²⁴⁸Cm leading to the new superheavy nuclide ²⁷¹Hs
Dvorak, J.*; Bröchle, W.*; Chelnokov, M.*; Düllmann, Ch. E.*; Dvorakova, Z.*; Eberhardt, K.*; Jäger, E.*; Krücken, R.*; Kuznetsov, A.*; Nagame, Yuichiro; Nebel, F.*; Nishio, Katsuhisa; Perego, R.*; Qin, Z.*; Schädel, M.*; Schausten, B.*; Schimpf, E.*; Schuber, R.*; Semchenkov, A.*; Thörle, P.*; Türler, A.*; Wegrzecki, M.*; Wierczinski, B.*; Yakushev, A.*; Yeremin, A.*
Physical Review Letters 100(13), p.132503_1-132503_4(2008) ; (JAEA-J 03998)

The analysis of a large body of heavy ion fusion reaction data with medium-heavy projectiles (6≤Z≤18) and actinide targets suggests a disappearance of the 3n exit channel with increasing atomic number of the projectile. Here, we report a measurement of the excitation function of the reaction ²⁴⁸Cm(²⁶Mg,xn)^274-xHs and the observation of the new nuclide ²⁷¹Hs produced in the 3n evaporation channel at a beam energy well below the Bass fusion barrier with a cross section comparable to the maxima of the 4n and 5n channels. This indicates the possible discovery of new neutron-rich transactinide nuclei using relatively light heavy ion beams of the most neutron-rich stable isotopes and actinide targets.

36000719
Tunable high-energy ion source via oblique laser pulse incident on a double-layer target
Morita, Toshimasa; Esirkepov, T. Z.; Bulanov, S. V.; Koga, J. K.; Yamagiwa, Mitsuru
Physical Review Letters 100(14), p.145001_1-145001_4(2008) ; (JAEA-J 03999)

The laser-driven acceleration of high quality proton beams from a double-layer target, comprised of a high-Z ion layer and a thin disk of hydrogen, is investigated with three-dimensional particle-in-cell simulations in the case of oblique incidence of a laser pulse. It is shown that the proton beam energy reaches its maximum at a certain incidence angle of the laser pulse, where it can be much greater than the energy at normal incidence. The proton beam propagates at some angle with respect to the target surface normal, as determined by the proton energy and the incidence angle.

36000720
Reply to "Comment on 'Uniformization of the transverse beam profile by means of nonlinear focusing method' "
Yuri, Yosuke; Miyawaki, Nobumasa; Kamiya, Tomihiro; Yokota, Wataru; Arakawa, Kazuo; Fukuda, Mitsuhiro*
Physical Review Special Topics; Accelerators and Beams 11(3), p.039002_1-039002_2(2008) ; (JAEA-J 04000)

We received the Comment on our recent publication [Y. Yuri et al., Phys. Rev. ST Accel. Beams 10, 104001 (2007)] on the nonlinear focusing method to uniformize the transverse beam profile. The Comment describes that the development done at Los Alamos National Laboratory (LANL) included our work. In order to clarify the difference of outcomes between our recent work and the LANL work outlined in the Comment, we briefly summarize the former progress of the research and development on beam uniformization by means of the nonlinear focusing method, and insist on the newness of our recent publication in this Reply.

36000721
Optimization of the viewing chord arrangement of the ITER poloidal polarimeter
Yamaguchi, Taiki; Kawano, Yasunori; Fujieda, Hirobumi; Kurihara, Kenichi; Sugihara, Masayoshi*; Kusama, Yoshinori
Plasma Physics and Controlled Fusion 50(4), p.045004_1-045004_15(2008) ; (JAEA-J 04001)

The poloidal polarimeter will be installed in the International Thermonuclear Experimental Reactor (ITER) to measure the safety factor profile. The number of viewing chords is restricted to about 15 channels. Therefore optimization of the viewing chord arrangement is necessary to diagnose the accurate safety factor profile. In this study, we studied the optimum viewing chord arrangement for the equilibria of ITER operation scenarios using the equilibrium reconstruction. For the burning phase of inductive scenario, the error of the safety factor on the magnetic axis was 35% if the viewing chords are not arranged in the peripheral region. It was improved to 3% by arranging the viewing chord of the upper port to peripheral region. This arrangement was used for the reconstruction of the burning phase in the noninductive scenario and of the phase of the plasma current 3.5 MA in the inductive operation scenario. As the result, the accuracy does not decrease drastically.

36000722
Core characteristics of fast reactor cycle with simple dry pyrochemical processing
Ikegami, Tetsuo
Progress in Nuclear Energy 50(2-6), p.206-211(2008) ; (JAEA-J 04002)

Fast reactor core concept and core nuclear characteristics are studied in the case of applying the simple dry pyrochemical processing for fast reactor mixed oxide spent fuels in the Compound Process Fuel Cycle. Results of the core nuclear analyses show the possibility to recycle FR spent fuel once and to have 1.01 of breeding ratio without radial blanket region, in a case of large FR core with half of loaded fuels are recycled through the simple dry pyrochemical processing. The comparison made among three kinds of recycle fuels, LWR UO₂ spent fuel, LWR MOX spent fuel, and FR spent fuel, has revealed that the recycle fuels, regardless of their starting heavy metal composition, reach an equilibrium state after recycles and that the recycled FR fuel has the lowest radio-activity and about same level of heat generation among the recycle fuels.

36000723
On a fast reactor cycle scheme that incorporates a thoria-based minor actinide-containing cermet fuel
Osaka, Masahiko; Takano, Sho*; Yamane, Yoshihiro*; Misawa, Tsuyoshi*
Progress in Nuclear Energy 50(2-6), p.212-218(2008) ; (JAEA-J 04003)

Concept of fast reactor cycle scheme that incorporates a thoria-based minor actinide-containing cermet fuel is given. The present cermet fuel consists of oxide solid solution of Th and minor actinides and Mo inert matrix. It has been proposed as a high-performance device that can enhance minor actinide transmutation in the fast reactor cycle. It is used in an independent small cycle, whereby dedicated cycle process are adopted. Two-steps process for reprocessing of the present cermet fuel was proposed; it consists of pre-removal of Mo-inert matrix and actinide recovery. A preliminary test for pre-removal of Mo-inert matrix using surrogate cermet fuel was carried out. It was done by dissolution in nitric acid at room temperature. Results showed that Mo-inert matrix was largely dissolved, while oxide remained. Burnup characteristics of a fast reactor core loaded with the cermet fuel were investigated by using neutronic calculation codes. It was revealed that a heterogeneous composition of Mo-inert matrix in inner and outer cores could lead to effective transmutation and flattened power density. It was concluded that the present cermet fuel is potentially a promising one as a high-performance transmutation device for the fast reactor.

36000724
Extraction separation of trivalent minor actinides from lanthanides with hydrophobic derivatives of TPEN
Matsumura, Tatsuro; Takeshita, Kenji*
Progress in Nuclear Energy 50(2-6), p.470-475(2008) ; (JAEA-J 04004)

We are developing a new MA/Ln separation process with TPEN and its derivatives for P&T technology. TPEN is a hexadentate ligand and a kind of podand type molecule and can encapsulate a metal ion. TPEN has good selectivity of Am(III) from Ln(III) and has potential to establish partitioning of MA. However, there is a serious problem for the practical application. This is to the dissolution of a slight amount of TPEN to water. High enrichment of Am(III) will be restricted by the dissolution of TPEN to water. In this study, the hydrophobicity of TPEN is improved by introducing alkyl groups and the effect of the introduction of alkyl groups on the separation of Am(III) and Eu(III) is examined. We synthesized three derivatives successfully. The derivatives were examined both the extractability and selectivity of Am(III) and Eu(III). One of them, tpdben, showed good selectivity and the maximum separation factor, SF_Am/Eu, was 35 at pH 5.06. A hydrophobic derivative of TPEN that has potential of application to the MA/Ln separation process was synthesized successfully.

36000725
A New back-end cycle strategy for enhancing separation, transmutation and utilization of materials (Adv.-ORIENT cycle)
Ozawa, Masaki; Suzuki, Tatsuya*; Koyama, Shinichi; Akatsuka, Hiroshi*; Mimura, Hitoshi*; Fujii, Yasuhiko*
Progress in Nuclear Energy 50(2-6), p.476-482(2008) ; (JAEA-J 04005)

For the minimization of the ecological burden originated in nuclear fuel recycling, a new R&D strategy was filed as "Adv.-ORIENT cycle". In the context, mutual precise separation of f-elements, such as minor actinide (MA)/lanthanides (Lns) and Am/Cm, are highly essential for enhancing the MA (²⁴¹Am) burning. The separation and utilization of rare metal fission products (RMFPs; Ru, Tc, etc) are a new direction in the partitioning and transmutation field. Separation of exothermic nuclides, ⁹⁰Sr, ¹³⁷Cs as well as MA, will significantly help to improve the repository tasks. A key separation media are ion exchange chromatography (IXC) by tertiary pyridine resin and a catalytic electrolytic extraction (CEE) by Pd_adatom. On challenging the isotope separation of LLFP, theoretical and laboratory studies were begun for ¹³⁵Cs, ¹²⁶Sn in the first priority.

36000726
Long-term Nuclear Knowledge Management (NKM) of Innovative Nuclear Energy Systems (INES); A Case study of the Japan Atomic Energy Research Institute (JAERI)
Yanagisawa, Kazuaki; Bezdek, R. H.*; Sawada, Tetsuo*
Progress in Nuclear Energy 50(2-6), p.683-687(2008) ; (JAEA-J 04006)

Within JAERI, funds invested in a 45 years study of LWR totaled 4.2 billion dollars (bd) for research and 3.4 bd (34,718 man years) for personnel. The benefits to taxpayers from this JAERI work was estimated to be about 6.3 bd, resulting in a favorable cost benefit ratio of 1.5. JAERI is a national research institute and this figure may be regarded as sufficiently high, and many high risk and complex tasks were completed successfully. Commercialized HTGR hasa retail cost of 0.36 bd a year and the share of JAERI is 0.018 bd a year. Estimate is that after commercialization of FR in 2050, a FR will generate revenue from electricity as high as 1,687 bd during the period from 2050 to 2100 which is greater than that of LWR. However, there is substantial uncertainty in these estimates. To achieve long term INES, it is necessary to develop the sustainable scenarios and the long-term robust NKM, as shown in the present study.

36000727
Physics and biology of protein
Go, Nobuhiro
Progress of Theoretical Physics Supplement (170), p.198-213(2008) ; (JAEA-J 04007)

This is a record of my lecture given at the occasion of Yukawa-Tomonaga Centennial Symposium. At first I will mention very briefly how Yukawa contributed to the development of biophysics in Japan. Then I will be concerned with the relationship between physics and biology by discussing various aspects of protein. How far and in what sense can physics approach the essence of protein? In what aspects are something beyond physics important?

36000728
Polyvinyl butyral films containing Leuco-Malachite Green as low-dose dosimeters
Hoang, H. M.*; Solomon, H. M.*; Taguchi, Mitsumasa; Kojima, Takuji
Radiation Physics and Chemistry 77(4), p.457-462(2008) ; (JAEA-J 04008)

Thin films containing leuco-malachite green (LMG) dye in polyvinyl butyral (PVB) have been developed for lower dose measurements of a few hundreds Gy level. The film shows significant color change in the visible range and the sensitivity of the film to absorbed dose was enhanced by addition of chloride containing compounds such as chloral hydrate or 2,2,2-trichloroethanol. The film is useful as dosimeters for dose measurements e.g. in food irradiation and environmental protection.

36000729
Application of voxel phantoms and Monte Carlo method to whole-body counter calibrations
Kinase, Sakae; Takagi, Shunji*; Noguchi, Hiroshi; Saito, Kimiaki
Radiation Protection Dosimetry 125(1-4), p.189-193(2007) ; (JAEA-J 04009)

In the Japan Atomic Energy Research Institute (JAERI), a calculation code -UCWBC code- for whole-body counter calibrations using voxel phantoms has been developed as an EGS4 Monte Carlo user code. To validate the UCWBC code for calibrating whole-body counters in JAERI, response functions and counting efficiencies of a p-type high-purity Ge semiconductor detector used for the whole-body counter were evaluated for a water-filled block-shape phantom by the UCWBC code and were measured by experiments. Furthermore, counting efficiencies of the Ge semiconductor detector for the male and female voxel phantoms developed in JAERI were evaluated in the photon energy range 60-1836 keV by the UCWBC code in order to examine the differences between the counting efficiencies for voxel phantoms. In conclusion, it was found that the response functions and counting efficiencies of the Ge semiconductor detector by the UCWBC code for the water-filled block-shape phantom are in good agreement with measured data. The UCWBC code was validated by the comparisons.

36000730
Development of a quasi-monoenergetic neutron field using the ⁷Li(p,n)⁷Be reaction in the energy range from 250 to 390 MeV at RCNP
Taniguchi, Shingo*; Nakao, Noriaki*; Nakamura, Takashi*; Yashima, Hiroshi*; Iwamoto, Yosuke; Sato, Daiki; Nakane, Yoshihiro; Nakashima, Hiroshi; Itoga, Toshio*; Tamii, Atsushi*; Hatanaka, Kichiji*
Radiation Protection Dosimetry 126(1-4), p.23-27(2007) ; (JAEA-J 04010)

A quasi-monoenergetic neutron field was developed using the reaction in the energy range from 250 to 390 MeV in the ring cyclotron facility at the Research Center for Nuclear Physics (RCNP), Osaka University. Neutrons were generated from a 10-mm thick Li target injected by 250, 350 and 392 MeV protons. The neutrons produced at 0 degree were extracted into the 100-m long TOF room through a 150-cm thick ironcollimator of 10 cm × 12 cm aperture, and were measured by a 12.7-cm diam. × 12.7-cm long NE213 organic liquid scintillator. This neutron field is very useful since experimental data for high energy neutrons in this energy region are very scarce. It has already been used for a neutron shielding experiment.

36000731
DARWIN: Dose monitoring system applicable to various radiations with wide energy ranges
Sato, Tatsuhiko; Sato, Daiki; Endo, Akira; Yamaguchi, Yasuhiro
Radiation Protection Dosimetry 126(1-4), p.501-505(2007) ; (JAEA-J 04011)

A new inventive radiation dose monitor, designated as DARWIN (Dose monitoring system Applicable to various Radiations with WIde energy raNges), has been developed for real-time monitoring of doses in workspaces and surrounding environments of high energy accelerator facilities. DARWIN satisfies the following features: (1) capable of monitoring doses from neutrons, photons and muons with wide energy ranges - from thermal energy to 1 GeV, 150 keV to 100 MeV, and 1 MeV to 100 GeV, respectively, (2) high sensitivity and precision - more than 10 times as sensitive as conventional moderator-based survey instruments for neutrons, (3) easy to operate with a simple user-interface, and (4) light weighted for movability. The details of the features will be described at the presentation, together with the results of the calibrations performed in several accelerator facilities.

36000732
Determination of deuterium location in Ba₃Ca_1.18Nb_1.82O_8.73
Shimoyama, Tomotaka*; Tojo, Takeo*; Kawaji, Hitoshi*; Atake, Toru*; Igawa, Naoki; Ishii, Yoshinobu*
Solid State Ionics 179(7-8), p.231-235(2008) ; (JAEA-J 04012)

The neutron diffraction study was carried out to determine the location of proton conducting mixed perovskite-type oxide Ba₃Ca_1.18Nb_1.82O_8.73 at 300K. The obtained data have been analyzed by the Rietveld method and the maximum entropy method. The crystal structure of the sample is refined on the basis of the cubic structure with the space group Fm-3m. We found that oxide ion locates at 24e site and deuterium 96j site, respectively. The distance between oxide ion and deuterium sites is about 0.72Å, which is shorter than the normal distance of OD group. The oxygen in OD group is shifted from 24e site slightly toward the opposite side of deuterium and the deuterium is shifted to the Ca/Nb mixed site.

36000733
Nuclear field shift effect of chromium(III) in repeated extraction using a crown ether
Fujii, Toshiyuki*; Suzuki, Daisuke; Yamana, Hajimu*
Solvent Extraction and Ion Exchange 26(2), p.100-112(2008) ; (JAEA-J 04013)

Chromium isotopes were fractionated by continuous extraction using dicyclohexano-18-crown-6 as an extractant. This system was designed for accumulating isotope effect into the aqueous phase. After a long period operation, the Cr isotope ratios in the residual aqueous phase were precisely measured by using a multi-collector thermal ionization mass spectrometer with the total evaporation technique. The analytical results showed a clear mass-independent isotope fractionation. The mass-independent property was consistent with that obtained from a batch extraction. The isotopic mass balance was verified to be preserved in the continuous extraction. The Bigeleisen's 1996 theory gave the consistent explanation on the Cr isotope effect, in which the mass-independent isotope effect was identified to be the nuclear field shift effect.

36000734
Strengthening the base for sustainable development of nuclear energy (in Japanese)
Nakatsuka, Toru
Denki Hyoron 92(7), p.32-37(2007) ; (JAEA-J 04015)

If nuclear energy in Japan is to contribute to a stable energy supply, industrial promotion, improvement of people's living standard, and sustainable development of society in the future, it is essential to maintain the R&D potential in the long and medium terms. This paper introduces JAEA's role and activities to strengthen the base of nuclear energy in Japan, such as human resource development, maintenance of facilities and intellectual property management.

36000735
Uranium resources' outlook and the key factors for its timely development (in Japanese)
Kobayashi, Takao
Denki Hyoron 92(11), p.16-20(2007) ; (JAEA-J 04016)

Uranium spot price is steeply up and down recently. However, since spot price had not always reflected the true market situation properly, we must carefully analyze the essential key factors, such as nuclear generation capacity trends, uranium resources availability, trends of exploration and development activities and the situation of secondary uranium sources, to outlook the future uranium resources' supply and demand. Even uranium resources are exist enough to sustain world nuclear generation for more than one century, as the generation capacity are projected to be growing steadily and existing important uranium mines will be exhausted one after another after 2020, it is very necessary to discover new deposits continuously and to develop new mines timely with long term prospects and strategy.

36000736
Current status of research and development at Japan Atomic Energy Agency (in Japanese)
Policy Planning and Administration Department
Denki Hyoron 93(2), p.73-91(2008) ; (JAEA-J 04017)

Japan Atomic Energy Agency (JAEA) was established as the result of the integration of Japan Atomic Energy Research Institute (JAERI) and Japan Nuclear Cycle Development Institute (JNC) on Oct. 1, 2005. This paper introduces the current status of research and development in FY2007.

36000737
Research and development of application programming interface for using grid environments (in Japanese)
Suzuki, Yoshio
FUJITSU Famirikai Rombunshu (Internet) , 15p.(2008) ; (JAEA-J 04018)

At the Japanese national project "Development and Applications of Advanced High-Performance Supercomputer", we have developed an application programming interface for a using grid computing environment in order to shift the grid-enabled application developed in ITBL project to the next generation national grid infrastructure. We have developed the prototype of API by analyzing how grid-enabled applications in ITBL project use the grid computing environment. Using this prototype enables to develop grid-enabled applications easily, to use different grid environments without changing applications and to interoperate different grid environments without changing grid middleware.

36000738
Recent progress of research and development on geological isolation of high-level radioactive waste (in Japanese)
Kawata, Tomio
Genshiryoku Shisutemu Nyusu 18(4), p.18-25(2008) ; (JAEA-J 04019)

Recent progress of research and development on geological isolation of high-level radioactive waste by JAEA is presented.

36000739
Aiming at establishment of a good system for J-PARC users (in Japanese)
Ikeda, Yujiro
Hamon 18(1), p.27-31(2008) ; (JAEA-J 04020)

As the J-PARC user operation is scheduled to start within one year, a system for the user program has been thoroughly discussed in the J-PARC team in terms of access policy, program review, beam-time fee, treatment of output, intellectual property protection policy, etc. This paper reports the general concept of the J-PARC user program system.

36000740
New system of nuclear education by network (in Japanese)
Hasegawa, Makoto; Nakanishi, Takashi*; Fujii, Yasuhiko*; Kodaka, Tomohiro*
Hosha Kagaku Nyusu (17), p.29-35(2008) ; (JAEA-J 04021)

36000741
Temporal and spatial distribution of plutonium released from Nagasaki atomic bomb (in Japanese)
Kokubu, Yoko
Hosha Kagaku Nyusu (17), p.49-50(2008) ; (JAEA-J 04022)

36000742
Contribution of positron imaging on the research aimed for phytoremediation of Cd-contaminated soil (in Japanese)
Nakamura, Shinichi*; Chino, Mitsuo*; Fujimaki, Shu; Suzui, Nobuo; Ishioka, Noriko; Kawachi, Naoki; Matsuhashi, Shimpei
Hoshasen To Sangyo (117), p.9-14(2008) ; (JAEA-J 04023)

36000743
Indexing policy for International Nuclear Information System (INIS) (in Japanese)
Yonezawa, Minoru
Joho No Kagaku to Gijutsu 58(4), p.178-183(2008) ; (JAEA-J 04025)

International Nuclear Information System (INIS) was founded in 1970 in order to foster scientific and technical information in the field of nuclear science and technology for peaceful purpose in cooperation with International Atomic Energy Agency (IAEA) member countries and related international organizations. INIS member countries collect nuclear related literatures and prepare input records and submit them to the IAEA/INIS Secretariat, and then INIS Secretariat merges those records from member countries into INIS database. In INIS, indexing has been conducted for effective information retrieval. It is important to keep consistency of indexing among INIS members and indexing is conducted mainly for title and abstract in each document based on the indexing manual. This paper describes general principle of indexing as well as specific rules applied for several fields.

36000744
Design and implementation of an atomic and molecular physics paper classification supporting system using abstracts (in Japanese)
Kashiwagi, Hiroe*; Takata, Masami*; Sasaki, Akira; Jo, Kazuki*
Joho Shori Gakkai Rombunshi; Suri Moderuka To Oyo 48(SIG15), p.189-198(2007) ; (JAEA-J 04026)

36000745
Etching behavior of poly(vinylidene fluoride) thin films irradiated with ion beams; Effect of irradiated ions and pretreatment (in Japanese)
Yamaki, Tetsuya; Rohani, R.*; Koshikawa, Hiroshi; Takahashi, Shuichi; Hasegawa, Shin; Asano, Masaharu; Voss, K.-O.*; Neumann, R.*; Maekawa, Yasunari
Kobunshi Rombunshu 65(3), p.273-276(2008) ; (JAEA-J 04027)

Poly(vinylidene fluoride) thin films irradiated with four kinds of ion beams were exposed to a 9 M KOH aqueous solution after their storage in air for 30 or 90 days at different temperatures. According to the conductometry, the heating at 120ºC was found to enhance the etch rate in the latent track without changing that in the bulk, thereby enabling us to obtain very high etching sensitivity for the preparation of nano-sized through-pores. The formation of hydroperoxides during this pretreatment should facilitate the introduction of the etching agent to improve etchability. Additionally, the irradiation of higher-LET ions, causing each track to more activated sites (like radicals), was preferable to achieve high sensitivity of the etching.

36000746
Visualization and quantification of water behavior around cracks by neutron radiography (in Japanese)
Kanematsu, Manabu*; Noguchi, Takafumi*; Maruyama, Ippei*; Iikura, Hiroshi
Konkurito Kogaku Nenji Rombunshu 29(1), p.981-986(2007) ; (JAEA-J 04028)

Neutron radiography is one of the non-destructive methods. In this research, neutron radiography was applied to visualize and quantify the water penetration into concrete through cracks. The radiographs were obtained by the TNRF (Thermal Neutron Radiography Facility) installed at a research reactor, JRR-3M, in the Japan Atomic Energy Agency (JAEA). The quantitative capability of neutron radiography for the water content and the penetration depth in cement paste specimen were confirmed. The effects of crack and water content on the velocity and the depth of water penetration into concrete were visualized with several concrete specimens, to which surface water was supplied through the container.

36000747
Development of fluorinated polymer electrolyte membranes using photografting methods (in Japanese)
Asano, Masaharu; Chen, J.; Maekawa, Yasunari; Yoshida, Masaru
Maku 33(2), p.63-69(2008) ; (JAEA-J 04029)

36000748
Impregnation of extractants to porous membrane by radiation-induced graft polymerization (in Japanese)
Asai, Shiho
Maku 33(2), p.70-77(2008) ; (JAEA-J 04030)

36000749
Electron tomographic observation of precipitates on lath boundaries in 10Cr ferritic steel bearing V (in Japanese)
Mitsuhara, Masatoshi*; Ikeda, Kenichi*; Hata, Satoshi*; Nakashima, Hideharu*; Wakai, Takashi
Materia 46(12), p.800(2007) ; (JAEA-J 04031)

High Cr ferritic steels bearing V have high creep strength due to the precipitation hardening. In order to enhance the efficiency of the precipitation hardening, the elemental components, shape and distribution of the precipitates should be comprehended. In this study, we investigated that of the precipitates in the 10Cr ferritic steel bearing V using the STEM-EDS analysis and the three-dimensional electron tomography (3D-ET) observation. The two types of precipitates on the lath boundaries could be observed, which were lump-shaped precipitates and film-shaped precipitates. They had the different elemental component. From the 3D-ET observation, it revealed that the film-shaped precipitates covered the lath boundary widely. Therefore, the film-shaped precipitates are expected to be effective for the stabilization of martensitic microstructure during the creep deformation.

36000750
Conceptual core design study of the Very High Temperature gas-cooled Reactor (VHTR); Upgrading the core performance by using multihole-type fuel (in Japanese)
Ohashi, Kazutaka; Nishihara, Tetsuo; Kunitomi, Kazuhiko; Nakano, Masaaki*; Tazawa, Yujiro*; Okamoto, Futoshi*
Nippon Genshiryoku Gakkai Wabun Rombunshi 7(1), p.32-43(2008) ; (JAEA-J 04032)

Interests on the development of the Very High-Temperature Gas-Cooled Reactor (VHTR), of which the reactor outlet temperature is 950°C or much higher, are recently increasing world-widely and it was selected as one of the candidate reactor types of the GIF. Japan Atomic Energy Agency has already initiated R&D efforts on the electricity and hydrogen co-generation plant with VHTR system, GTHTR300C. Although technical feasibility of its VHTR reactor using Pin-in-block fuel, which has experience to be already used in the HTTR, has been shown fundamentally, more improvements of the core performances, such as decrease of the occupational exposure doses during the plant maintenance, are desired. This report presents the results of the conceptual core design study using Multi-hole type fuel and the study on the occupational exposure doses. The latter results shows much better plant maintainability compared to the previous results of the GTHTR-300.

36000751
Thermal-hydraulic experiment on beam window for developing the accelerator-driven transmutation system (in Japanese)
Hayashi, Kenichi*; Ono, Mikinori*; Kikuchi, Kenji; Tokunaga, Noriya*; Kitano, Teruaki*; Oigawa, Hiroyuki
Nippon Genshiryoku Gakkai Wabun Rombunshi 7(1), p.44-57(2008) ; (JAEA-J 04033)

Accelerator driven nuclear transmutation system aims at transmuting minor actinides and long-lived fission products to stable or short-lived nuclei. A design study of proton beam window, which is an interface component between accelerator and nuclear reactor. Thermal-hydraulic experiment of the beam window was done. Two experiments were conducted: one was particle image velocimetry measurement around the beam window in flowing water and the other was temperature measurement at the beam window under flowing lead bismuth. Numerical simulation was also done to validate the beam window model for design work. Results show that heat transfer characteristics of the beam widow averaged in space and with time under flowing lead bismuth was formulized by the experimental equation. Numerical simulation model can estimate the mean heat transfer coefficient. However, a local heat transfer coefficient was not stable: it fluctuates with time and even in space, especially around stagnation point.

36000752
Development of water electrolysis cell for hydrogen production utilizing sulfur dioxide (in Japanese)
Nakagiri, Toshio; Yamaki, Tetsuya; Asano, Masaharu; Tsutsumi, Yasuyuki*
Nippon Genshiryoku Gakkai Wabun Rombunshi 7(1), p.58-65(2008) ; (JAEA-J 04034)

Water electrolysis utilizing sulfur dioxide is attractive for low electricity consumption hydrogen production and has been investigated for the electrolytic and thermo-chemical hybrid hydrogen production process utilizing the heat generation of nuclear power plant. In this study, hydrogen production performance of water electrolysis cell utilizing sulfur dioxide gas and sulfur dioxide cross-over prevention performance of several polymer electrolytes were investigated experimentally.

36000753
Trend analysis of incidents involving setpoint drift in safety or safety/relief valves at U.S. LWRs (in Japanese)
Watanabe, Norio
Nippon Genshiryoku Gakkai Wabun Rombunshi 7(1), p.74-84(2008) ; (JAEA-J 04035)

Since the beginning of 1980's, in the United States, there have been many licensee event reports (LERs) involving setpoint drift in safety or relief valves. The NRC has issued a lot of generic communications on this issue and the industry has made its efforts to resolve the issue. The NRC staff recently highlighted that over 70 LERs involved instances where these valves failed to meet the allowed setpoint tolerance from 2001 through August 2006. In this study, we analyzed the U.S. experience with setpoint drift in safety relief valves (SRVs) at BWRs, pressurizer safety valves (PSVs) and main steam safety valves (MSSVs) at PWRs by reviewing the LERs from 2000 to 2006 and examined the trend. It is found that for SRVs and MSSVs, the disc-seat bonding is a dominant cause of setpoint drifting high and has a tendency to result in relatively large deviation of setpoint. For PSVs, the deviation of setpoint is generally small although the causes are not specified in many instances.

36000754
A Review of activities for risk-informed criticality safety assessment in U.K., U.S.A. and Japan (in Japanese)
Tamaki, Hitoshi; Naito, Yoshitaka*; Suzuki, Tadakazu*; Mitsuhashi, Takeshi*
Nippon Genshiryoku Gakkai-Shi 50(2), p.97-102(2008) ; (JAEA-J 04036)

36000755
Overview of Japan Proton Accelerator Research Complex (J-PARC) project and Materials and Life Science Experimental Facility (MLF) (in Japanese)
Ikeda, Yujiro
Nippon Kessho Gakkai-Shi 50(1), p.2-6(2008) ; (JAEA-J 04037)

The J-PARC project has been conducted jointly by JAERI and KEK since 2001. This paper reports an overview and current status of the project. The high intensity proton accelerator consists of a 400 MeV Linac, a 3 GeV synchrotron and 50 GeV synchrotron to deliver MW level pulsed proton beam to experimental facilities. The MW proton power will provide an advanced scientific experimental research complex aiming at making breakthroughs in materials and life science with neutron and muon, nuclear and elementary physics, etc. Regarding the project being close to its completion in 2008, this paper describes the overview of J-PARC project with emphasis of the Materials and Life Science Experimental Facility, in which the MW pulsed neutron and muon sources, are placed to provide high quality neutron and muon beams to the world wide users.

36000756
New development in nanostructure analysis by smaller-angle neutron scattering instrument of J-PARC (in Japanese)
Suzuki, Junichi; Shinohara, Takenao; Takata, Shinichi; Oku, Takayuki; Suzuya, Kentaro; Aizawa, Kazuya; Arai, Masatoshi; Otomo, Toshiya*; Sugiyama, Masaaki*
Nippon Kessho Gakkai-Shi 50(1), p.24-28(2008) ; (JAEA-J 04038)

36000757
Effects of electro-slag remelting on inclusion formation and impact property of reduced activation ferritic/martensitic steels (in Japanese)
Sawahata, Atsushi; Tanigawa, Hiroyasu; Enomoto, Masato*
Nippon Kinzoku Gakkai-Shi 72(3), p.176-180(2008) ; (JAEA-J 04039)

36000758
OR methodologies toward the deployment of better fast reactor and fuel cycle system (in Japanese)
Shiotani, Hiroki
Opereshonzu, Risachi 53(4), p.210-216(2008) ; (JAEA-J 04040)

Recently, A project, which is called "FaCT project", has been initiated which aims to the deployment of fast breede reactor(FR) cycle system. Adding to the element technologies development and the demonstration of the innovative technologies through equipment tests, synthetic evaluation methodologies of FR cycle system including scenario study, DCF method, Analytic Hierarchical Process, real options approach, supply chain management, etc. are under development. It is necessary for many people to make a large scale long-term efforts to deploy FR cycles; and more utilization of OR is expected for deriving the benefits from the modeling of the nuclear energy systems and the knowledge management of them.

36000759
The Effects of rhizosphere pH on Cd uptake of soybean seedlings
Oya, Tomoyuki*; Rai, Hiroki*; Tanoi, Keitaro*; Iikura, Hiroshi; Nakanishi, Tomoko*
Radioisotopes 56(11), p.729-736(2007) ; (JAEA-J 04041)

To study the effect of rhizosphere pH on the cadmium(Cd) uptake, soybean seedlings were grown for 4 days in 0.2 mM CaCl₂ solution containing 1 μM Cd under pH 4.5 or pH 6.5 using ¹⁰⁹Cd as a tracer. The concentration of Cd in root at pH 6.5 was 3.4 times higher than that at pH 4.5. Cadmium amount absorbed on root surface at pH 6.5 was 1.3 times higher than that at pH 4.5. With high accumulation of Cd in root, Cd toxicity such as brownish of the tissue and the suppression of lateral root development was only observed under pH 6.5 condition. Transpiration rate was found to have no relation to high accumulation of Cd in shoot.

36000760
The Influence of nitrate on dissolution behavior of cement hydrates (in Japanese)
Fujita, Hideki*; Negishi, Kumi*; Osawa, Tsutomu*; Honda, Akira
Semento, Konkurito Rombunshu (61), p.262-269(2008) ; (JAEA-J 04042)

The influence of sodium nitrate on dissolution of cement hydrates was investigated by flow through experiment. Dissolution of portlandite was accelerated in NaNO₃ solution of 1 mol dm^-3 than in ion exchanged water. The acceleration of portlandite dissolution attributed to impact of ionic strength on the activities of aqueous species, because Ca concentration in 1 mol kg^-1 NaNO₃ solution equilibrated with portlandite was estimated to be 1.5 times as high as that in pure water. After flow through experiment, compressive strength fell down and porosity was higher than blank test using pure water. However low permeabilities were contradictory kept during NaNO₃ solution flowing. Dense existence of Na was possible to cause the low permeability during NaNO₃ solution flowing.

36000761
A Visit to the libraries; Public libraries of Singapore (in Japanese)
Ikeda, Kiyoshi
Senmon Toshokan (227), p.65-69(2008) ; (JAEA-J 04044)

36000762
"JAEA Abstracts" and "JOPSS"; Pioneer of institutional repository (in Japanese)
Gonda, Mayuki; Ikeda, Kiyoshi; Ebisawa, Naomi*
Senmon Toshokan (228), p.26-32(2008) ; (JAEA-J 04045)

Japan Atomic Energy Agency (JAEA) has disseminated research results via the Internet from before institutional repositories are provided by many universities and institutes. JAEA Library is providing 2 systems, "JAEA Abstracts" and "JOPSS" (JAEA Originated Papers Searching System) today. In this article, the history and the present situation of dissemination of JAEA's research results are reviewed.

36000763
Long term efficiency and stability of MX precipitation strengthening of high chromium steel (in Japanese)
Onizawa, Takashi; Ando, Masanori; Wakai, Takashi; Asayama, Tai; Kato, Shoichi
Tetsu To Hagane 94(3), p.91-98(2008) ; (JAEA-J 04046)

Employment of high Cr steel as a main structural material is considered as a way to achieve economical competitiveness of fast breeder reactors. A series of trial products controlling V and Nb contents is produced and aging tests are conducted to investigate the long term stability of the MX strengthening mechanism. Before and after a long term aging process, metallurgical examinations and quantitative analyses are conducted to investigate the stability of MX particles. After aging, Z-phase was observed in high Cr steel content Nb. With precipitation and rapid coarsening of Z-phase, decrease in number of density of MX particles. Therefore, it is supposed that the long term efficiency of MX precipitation strengthening mechanisms is decrease in high Cr steel content Nb. In contrast, it is expected that VX precipitation strengthening mechanisms is stable in high Cr steel content only V, because Z-phase isn't precipitate and VX is stable after aging.

36000764
Spent fuel reprocessing process by selective sulfurization (in Japanese)
Sato, Nobuaki*; Sato, Soichi
Tohoku Daigaku Tagen Busshitsu Kagaku Kenkyujo Sozai Kogaku Kenkyu Iho 63(1-2), p.69-76(2007) ; (JAEA-J 04047)

For the recovery of nuclear materials from spent oxide fuel, a selective sulfurization method was examined. Sulfurization behavior of uranium and fission products such as rare-earths, was investigated by XRD analysis as well as thermodynamic consideration. The sulfurization behavior of PuO₂ was also investigated by using CeO₂ as a stand-in of PuO₂. The results are summarized as follows; (1)At voloxidation, a part of U₃O₈ changed to rare-earth doped UO₂ solid solution in the presence of rare-earths. (2)Rare-earth oxides were selectively sulfurized, while U₃O₈ was reduced to UO₂. (3)CeO₂ showed a similar sulfurization behavior to that of UO₂. (4)The sulfurized rare-earths selectively dissolved into nitric acid, while UO₂ did not. (5)Sulfurization behaviors of other fission products such as Cs, Sr and platinum group were discussed by thermodynamic consideration. (6)Process for recycling nuclear materials as oxides by selective sulfurization was proposed.

36000765
Absolute neutron emission measurement in burning plasma experiments
Nishitani, Takeo; Ishikawa, Masao; Kondoh, Takashi; Kusama, Yoshinori; Asai, Keisuke*; Sasao, Mamiko*
AIP Conference Proceedings 988 , p.267-274(2008) ; (JAEA-J 04051)

36000766
Development in diagnostics application to control of advanced tokamak plasma
Koide, Yoshihiko
AIP Conference Proceedings 988 , p.413-419(2008) ; (JAEA-J 04052)

An economically attractive DEMO requires a steady-state plasma with high bootstrap-current fraction fBS and high normalized beta. Development in diagnostic application to control of such advanced tokamak plasma is in progress worldwide, which will be discussed in this talk. For example, plasmas with a fraction of DEMO-relevant fBS of 70% have been sustained for 8s in JT-60 by real-time control of toroidal plasma flow based on the current profile measurement by which moderate relaxation of pressure gradient is induced, resulting into avoidance of collapse triggered at integer q_min surfaces. In this experiment, change in the q value as a response to the pressure-gradient control was found to become big in the high fBS regime. Issues on (1) application of the present-day control methods to DEMO with self-heating, and (2) limitation of port space for the advanced control to keep a sufficient tritium-breeding ratio are also addressed.

36000767
Nanofabrication of block copolymer bulk and thin films; Microdomain structures as templates
Hashimoto, Takeji; Fukunaga, Kenji*
Nanostructured Soft Matter; Experiment, Theory, Simulation and Perspectives , p.45-97(2007) ; (JAEA-J 04054)

This work reviews the principles developed by the authors' group concerning the nanotechnology based on nanofabrications of the ordered structures of block copolymers (bcps) in thin films and bulks. We first discuss various methods to control ordered multiphase structures of bcps having nanoperiodicity. One of the ordered phase was selectively transformed into an empty phase or incorporated by metal nanoparticles such as palladium.

36000768
Profile measurement and transverse matching in J-PARC linac
Akikawa, Hisashi*; Igarashi, Zenei*; Ikegami, Masanori*; Lee, S.*; Sato, Susumu; Shen, G.; Tomisawa, Tetsuo; Ueno, Akira
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet) , p.1472-1474(2007) ; (JAEA-J 04055)

Beam commissioning of J-PARC linac has been performed since November 2006. We have wire scanners in order to measure beam profile and perform transverse matching. Four wire scanners are installed at each matching section. We report the result of measurement of beam profile and matching.

36000769
RF feedback control systems of the J-PARC linac
Fang, Z.*; Anami, Shozo*; Michizono, Shinichiro*; Yamaguchi, Seiya*; Kobayashi, Tetsuya; Suzuki, Hiroyuki
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet) , p.2101-2103(2007) ; (JAEA-J 04056)

The commissioning of the J-PARC 181-MeV proton linac was started from October of 2006. The RF sources of the linac consist of 4 solid-state amplifiers and 20 klystrons. In each RF source, the RF fields are controlled by a digital RF feedback (FB) system installed in a compact PCI (cPCI) to realize the accelerating field stability of ±1% in amplitude and ±1 degree in phase. In this paper the performance of the RF feedback control systems will be reported in detail.

36000770
Performance of J-PARC linac RF system
Kobayashi, Tetsuya; Chishiro, Etsuji; Hori, Toshihiko; Suzuki, Hiroyuki; Yamazaki, Masayoshi; Anami, Shozo*; Fang, Z.*; Fukui, Yuji*; Kawamura, Masato*; Michizono, Shinichiro*; Nammo, Kesao*; Yamaguchi, Seiya*
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet) , p.2128-2130(2007) ; (JAEA-J 04057)

High power operation of all the RF systems of J-PARC linac was started for the cavity conditioning in October 2006. Twenty 324-MHz klystrons have supplied the power to the accelerating cavities successfully, and the beam commissioning was started in November 2006. The RF drive and control systems are working well, and required stability is satisfied.

36000771
Comparison of trajectory between modeling and experiment for J-PARC linac
Okawa, Tomohiro; Ao, Hiroyuki; Sako, Hiroyuki; Ueno, Akira; Hasegawa, Kazuo; Ikegami, Masanori*
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet) , p.3324-3326(2007) ; (JAEA-J 04058)

In the beam commissioning of J-PARC linac, we use three simulations codes for accelerator modeling, which includes TRACE3D, XAL online model and PARMILA. TRACE3D is mainly used to determine the initial configuration for quadrupole magnets, XAL online model is mainly used for the transverse matching and orbit correction and PARMILA is mainly used to model phase-slip effects in a phase-scan tuning. We have compared the modeling with the experimental results obtained in the beam commissioning to date, where a basic agreement has been confirmed between the modeling and the actual beam behavior.

36000772
Characterization of hexagonal boron carbonitride (h-BCN) films prepared by RF plasma enhanced CVD
Mannan, M. A.*; Nagano, Masamitsu*; Hirao, Norie*; Baba, Yuji
Proceedings of 24th Japan-Korea International Seminar on Ceramics , p.289-292(2007) ; (JAEA-J 04059)

Boron carbonitride thin films were synthesized on Si(100) substrate by radiofrequency and microwave plasma enhanced vapor deposition using tris-dimethylamino borane as a precursor. The formation of the hexagonal phase of BCN films was confirmed by Fourier-transform infrared (FT-IR) spectroscopy. The measurements of X-ray photoelectron spectra (XPS) showed that boron atoms bonded to C and N atoms. The results for near edge X-ray absorption fine structures (NEXAFS) using synchrotron radiation supports the XPS results where B atoms bonded not only to nitrogen but also to carbon atoms to form various local structures. The polarization dependence of NEXAFS suggested that the local structures of BCN have different orientations in the films.

36000773
Design and scenario studies on FLWR for effective use of Pu
Iwamura, Takamichi; Ishikawa, Nobuyuki; Okubo, Tsutomu
Proceedings of 4th Asian Specialist Meeting on Future Small-Sized LWR Development , p.11-1-11-9(2007) ; (JAEA-J 04060)

An advanced LWR concept of Innovative Water Reactor for Flexible fuel cycle (FLWR) has been established based on the well-experienced LWR technologies. The feature of this concept is that the high conversion type core (HC-FLWR) with small technical gap from current LWR technologies can be proceed to the breeding type FLWR core, named Reduced-Moderation Water Reactor (RMWR) under the same core configuration and reactor systems. This paper describes the investigations on designs and introduction scenario of FLWR.

36000774
Perspective and current status on fuel cycle system of Fast reactor Cycle Technology development (FaCT) project in Japan
Funasaka, Hideyuki; Ito, Masanori
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM) , p.259-267(2007) ; (JAEA-J 04061)

FaCT Project taking over from Feasibility Study on Commercialized FR cycle system (FS) has been launched in 2006 by Japanese joint team with the participation of all parties concerned in Japan. Combination system of (the sodium-cooled reactor,) the advanced aqueous reprocessing system and the simplified pelletizing fuel fabrication (MOX fuel) is evaluated as the most promising fuel cycle system concept so that it has potential conformity to the design requirements, as well as a high level of technical feasibility as the final report of Phase II in FS. Current status and R&D prospects for this combination system of the advanced aqueous reprocessing system and the simplified pelletizing fuel fabrication (MOX fuel) system until around 2015 have been studied.

36000775
Long-term Nuclear Knowledge Management (NKM) on nuclear production of hydrogen; A Case study of the Japan Atomic Energy Research Institute (JAERI)
Yanagisawa, Kazuaki
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM) , p.820-826(2007) ; (JAEA-J 04062)

Within JAERI funds invested in the 32-year study of a high temperature gas-cooled reactor (HTGR) were 1.8 billion dollars (BD); 1.5BD for research and development (R&D) and 0.3BD for personnel (2,966 man-years). Commercialized HTGR will result in a cost reduction of electricity during power generation and also of that for hydrogen energy production. Accumulating market operation of products (MCP) of JAERI from 2010 to 2050 will be 0.29BD for the former and 1.2BD for the latter. The net benefit of JAERI investments to taxpayers thus totals 1.5BD. JAERI is a national research institute and this figure may be acceptable because JAERI has been completed successfully many high risk and complex tasks. However, there is substantial uncertainty in these estimates. To achieve long-term innovative nuclear energy systems, it is necessary to develop the sustainable scenarios and the long-term robust nuclear knowledge management as shown in the present study.

36000776
Evaluation of the cell voltage of electrolytic HI concentration for thermochemical water-splitting iodine-sulfur process
Tanaka, Nobuyuki; Yoshida, Mitsunori; Okuda, Hiroyuki; Sato, Hiroyuki; Kubo, Shinji; Onuki, Kaoru
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM) , p.833-836(2007) ; (JAEA-J 04063)

Breakdown of the cell voltage in the electro-electrodialysis process for concentrating HIx solution (HI-H₂O-I₂ mixture) was preliminarily examined in an effort to clarify the optimal operation condition as well as to optimize the cell design for the application to the thermochemical water-splitting IS process for large-scale hydrogen production. Basic data such as electric resistance of HIx solution, overvoltage of the iodine-iodide ion redox reaction at graphite electrode, and the membrane voltage drop, were measured using HIx solution with composition of interest. Also, a methodology for estimating the cell voltage was discussed. The calculated cell voltage agreed well with the experimental one indicating the validity of the procedure adopted.

36000777
Advanced LWR concept of FLWR for TRU recycling
Iwamura, Takamichi; Okubo, Tsutomu; Uchikawa, Sadao
Proceedings of International Conference on Advanced Nuclear Fuel Cycles and Systems (Global 2007) (CD-ROM) , p.1718-1724(2007) ; (JAEA-J 04064)

An advanced LWR concept of FLWR for TRU recycling has been investigated. The design study has shown the promising results for the feasibility of the concept, in conjunction with the investigated results obtained from the related R&D's for some key issues of FLWR development. In order to establish a robust nuclear energy supply system for the future, an appropriate combination of both the LWR and the FBR technologies, i.e. FLWR and Na-FBR, is considered to be preferable and realistic. This type of preferable combination is proposed in this paper.

36000778
Electrical characteristics of 6H-SiC MOSFETs after high dose irradiation
Oshima, Takeshi; Hishiki, Shigeomi*; Iwamoto, Naoya; Reshanov, S. A.*; Pensl, G.*; Kojima, Kazutoshi*; Kawano, Katsuyasu*
Proceedings of the 26th Symposium on Materials Science and Engineering, Research Center of Ion Beam Technology Hosei University , p.31-34(2007) ; (JAEA-J 04065)

36000779
Intense femto-second laser-driven X-ray source coupled with multiple directional quantum beams for applications
Daido, Hiroyuki; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Yogo, Akifumi; Mori, Michiaki; Li, Z.*; Kiriyama, Hiromitsu; Kanazawa, Shuhei; Akutsu, Atsushi; Nakai, Yoshiki; Pirozhkov, A. S.; Bulanov, S. V.; Esirkepov, T. Z.; Kimura, Toyoaki; Tajima, Toshiki; Nemoto, Koshichi*; Oishi, Yuji*; Nayuki, Takuya*; Fujii, Takashi*; Zhidkov, A.*; Noda, Akira*; Nakamura, Shu*; Choi, I. W.*; Yu, T. J.*; Sung, J. H.*; Kim, H. T.*; Jeong, T. M.*; Hong, K.-H.*; Kim, J.-H.*; Noh, Y.-C.*; Ko, D.-K.*; Lee, J.*; Nashima, Shigeki*; Shimizu, Kohei*; Hosoda, Makoto*
X-ray Lasers 2006 , p.595-605(2007) ; (JAEA-J 04066)

At present, using ultra-short high intensity lasers at APRC, JAEA Kansai photon research institute, we are developing laser driven multiple quantum beams such as protons, X-rays, electrons and THz waves. These beams are perfectly synchronized with each other. The pulse duration of each beam is lass than a pico-second. They have sharp directionality with high brightness. If we properly combined these, we have new pump-probe techniques for various applications.

36000780
Fluctuation of radiation dose-rate during winter thunderstorm (in Japanese)
Torii, Tatsuo; Okuyama, Shinichi; Nozaki, Tatsuo; Okubo, Koichi; Sugita, Takeshi*; Muraki, Yasushi*
Chimondai Ni Yoru Saiensu; Kyokugen Enerugi Uchubutsuri Kara Chikyukagaku Made , p.211-217(2008) ; (JAEA-J 04067)

The dose rate of the γ-rays increases in association with the activities of the thunderstorm. They were observed on the ground in the winter season of Japan. In addition to the measurement by the environmental radiation monitors set up around the fast breeder reactor, Monju, the radiation detectors were prepared which consist of the long proportional counters. The results were compared with the results measured at the same time by the environmental radiation monitors. The following two types of the radiation enhancements have been found during the winter thunderstorm activities; the gradual variation of photon intensity with energy up to a few MeV, and the burst type of the radiation that is attributed to the injection of high energy photons with the energy over 10 MeV. In this paper, we present the observed results during winter thunderstorms, and mention the runaway breakdown produced by the incidence of energetic radiation into thunderclouds.

36000781
Appropriate formulation of gas-liquid two phase flow simulation on unstructured mesh (in Japanese)
Ito, Kei; Kunugi, Tomoaki*; Yamamoto, Yoshinobu*
Dai-21-Kai Suchi Ryutai Rikigaku Shimpojiumu Koen Yoshishu (CD-ROM) , 5p.(2007) ; (JAEA-J 04068)

To evaluate gas entrainment phenomena in fast reactor systems accurately, we are developing a high-precision gas-liquid two-phase flow simulation method on the unstructured mesh. As a part of the development, an appropriate formulation was newly derived based on collocated variables' distributions employed in our unstructured simulation method. This formulation satisfied a mechanical balance between surface tension and pressure gradient at interfacial region. A definition formula of each phase's velocity near interfacial mesh cell was also improved to calculate physically correct velocity. The improved method was verified by simulating a rising air bubble in static water. It was confirmed that the new formulation eliminated unphysical interfacial behaviors induced by inappropriate formulations, and led similar air bubble shapes with experimental data both on the structured and the unstructured meshes.

36000782
Development of physical model describing the dynamic interaction characteristics of component connections for the analysis of an entire nuclear facility (in Japanese)
Nishida, Akemi
Dai-2-Kai Genshiryoku Shisutemu Kenkyu Kaihatsu Jigyo Seika Hokokukai Shiryoshu , p.196-197(2008) ; (JAEA-J 04069)

The objective of this project is to contribute to the seismic design evaluation of nuclear facilities through the construction of a numerical evaluation system which is able to evaluate both global and local behaviors of facilities under severe seismic events especially for next-generation nuclear system. As one of the technology components to realize this objective, we are developing and incorporating into the system a physical model describing the dynamic interaction characteristics of component connections. In this paper, we summarized about a proposal of a connection interaction model and tuning, and making of test models for hybrid experiment as research and development result of this project for FY2006.

36000783
Energy problems (in Japanese)
Shibata, Takemasa
Gendai Shakai To Kagaku Gijutsu , p.75-101(2008) ; (JAEA-J 04072)

The modern society uses a large quantity of energy of a one-10,000th of radiant energy given the earth from the sun. The present fossil energy consumption continues only in around 100 from dozens of years. The consumption of the fossil energy causes global warming. There is a problem to renewable energy and the atomic energy which can solve these in various ways. For future energy use, economy and politics are important, too.

36000784
FBR cycle development (in Japanese)
Negishi, Hitoshi; Chiyatani, Keiji; Tanigawa, Shingo
Genshiryoku Nenkan 2008-Nen Ban , p.53-61(2007) ; (JAEA-J 04073)

The Japanese government assessed the result of "Feasibility Study on Commercialized FR Cycle System 2nd Phase" and a major concept that is the combination of a sodium cooled FBR(oxide fuel), an advanced aqueous reprocessing and a simplified pelletizing was selected. From now on, the JAEA invests the development resource to a major concept intensively, and aims to put it to practical use by new project, "FaCT". In "Monju", the plant improvement construction have been working on schedule, and the various tests for restart are advanced. The R&D results in "Monju" will be applied to FBR development near future. "Joyo" has been operated over 70,000 hours, and has provided the fields to develop FBR fuel & material. In addition, the external utilization of "Joyo" is enhancing now. FBR development is activating worldwide. The international cooperation under GIF, GNEP and INPRO and the research collaboration with America/France are carrying.

36000785
Performance test results of intruder automated monitoring system (in Japanese)
Tanuma, Koji; Shimizu, Kazuaki; Hiruta, Toshihito; Kimura, Naoyuki; Suzuki, Mitsutoshi; Ito, Toru
Kaku Busshitsu Kanri Gakkai (INMM) Nippon Shibu Dai-28-Kai Nenji Taikai Rombunshu (CD-ROM) , 7p.(2007) ; (JAEA-J 04074)

JAEA is developing practical use of an intruder automated monitoring system aimed at early detection of intruders or suspicious objects entering into a site boundary or protected areas, etc. The system is aimed at rationalization and efficiency of guard functions by using monitoring camera and image analysis software to watch the action of intruder or suspicious individual. This paper introduces the results of comparative investigations, including the performance and function of intrusion detection, expansion of the system, the test results of environmental resistance over a long period of time (ex. climate conditions, small animals, weeds, behavior of intruders, etc.). The effectiveness of the monitoring system as a physical protection measure, and the scope of application other than nuclear facility are evaluated using typical foreign image analysis software.

36000786
The Remote transmission test of the GUAM measurement data by the wireless LAN (in Japanese)
Asano, Takashi; Fujiwara, Shigeo; Takahashi, Saburo; Nemoto, Tadayuki*; Sato, Takashi*; Kuniyasu, Kazufusa*; Hiruta, Kazuhiko*
Kaku Busshitsu Kanri Gakkai (INMM) Nippon Shibu Dai-28-Kai Nenji Taikai Rombunshu (CD-ROM) , 11p.(2007) ; (JAEA-J 04075)

JAEA has developed and demonstrated the Remote Monitoring (RM) technology on the safeguards equipment at the storage area in PFPF to improve the efficiency of the inspection activity. JAEA is considering the expansion of the RM technology to the safeguards equipment in the process area to improve the efficiency of the inspection activity under the integrated safeguards. JAEA considers that the cabling cost and work in the facility will be reduced to apply the wireless LAN to the RM technology. JAEA performed the confirmatory testing of the performance of the Glove box Unattended Assay and Monitoring system (GUAM) and the remote transmission of the GUAM measurement data by the wireless LAN in cooperation with Japan Nuclear Fuel Limited. In this test, JAEA confirmed it's possible to establish the wireless LAN networking in the process area. This paper reports the applicability of the wireless LAN to the RM technology based on the results of the confirmatory testing.

36000787
Synthetic evaluation method for fast reactor cycle with AHP and utility theory, etc. (in Japanese)
Shiotani, Hiroki
Kigyo, Gyosei No Tameno AHP Jireishu; Ishi Kettei Shien Tsuru No Jozu Na Katsuyoho , p.2-30(2007) ; (JAEA-J 04076)

In the Feasibility Study Phase 2 final evaluation, 20 candidate Fast Reactor (FR) cycle concepts were evaluated from six viewpoints including safety, economics, environmental burden reduction, efficient utilization of natural uranium resources, and nuclear non-proliferation in the multidimensional evaluation. Analytical Hierarcy Process (AHP) was used in the weighting of the viewpoints and the framework of Multi Attribute Utility Theory (MAUA) was also used in the evaluation. The FR cycle with soudium-cooled fast reactor was considered as the most promising concepts from the synthetic evaluation result for various reactor systems.

36000788
Research and development on environmental radionuclides for nuclear non-proliferation at Japan Atomic Energy Agency (in Japanese)
Usuda, Shigekazu; Shinohara, Nobuo; Sakurai, Satoshi; Magara, Masaaki; Miyamoto, Yutaka; Esaka, Fumitaka; Yasuda, Kenichiro; Kokubu, Yoko; Hirayama, Fumio; Lee, C. G.; Inagawa, Jun; Suzuki, Daisuke; Iguchi, Kazunari; Oda, Tetsuzo; Kumata, Masahiro; Yamamoto, Yoichi
KEK Proceedings 2007-16 , p.13-22(2008) ; (JAEA-J 04110)

For the purpose of controlling and monitoring radiations and radioactive materials emitted from nuclear facilities to the environment and also evaluating their effects, various R&D on environmental radioactivity has been carried out at Japan Atomic Energy Agency (JAEA). Especially, for the abolition of nuclear weapons and for peaceful uses nuclear energy, ultra-trace analysis of environmental samples for safeguards and ultra-high sensitive monitoring of radionuclides for the CTBT verification, which have been scheduled in the middle of 1990s, have been promotted under the auspices of the Japanese Government at JAERI, the former of JAEA. In this presentation, the outline of R&D on environmental radioactivity for nuclear non-proliferation is introduced. In addition, applications of the developed techniques and future perspectives will be discussed.

36000789
Leakage of water containing radioactive materials inside the controlled area of the experimental fast reactor Joyo (in Japanese)
Ohara, Norikazu; Suzuki, Toshiaki; Isozaki, Kazunori
UTNL-R-0466 , p.6-1-6-11(2008) ; (JAEA-J 04111)

36000790
Renewal of the reactor facilities for JMTR (in Japanese)
Gorai, Shigeru; Hanawa, Yoshio; Ebisawa, Hiroyuki; Oto, Tsutomu; Fukasaku, Akitomi
UTNL-R-0466 , p.1-2-1-1-2-8(2008) ; (JAEA-J 04112)

36000791
Design plan of irradiation facility in JMTR; Mo production by irradiation facility (in Japanese)
Iimura, Koichi; Hori, Naohiko; Kanno, Masaru
UTNL-R-0466 , p.1-3-1-1-3-9(2008) ; (JAEA-J 04113)

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JAEA > JAEA Library > JOPSS > Papers Published in Journals [Back Issues] > May 2008