JAEA Abstracts

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

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

September 2008

36001154
Benchmarking of calculated projectile fragmentation cross-sections using the 3-D, MC codes PHITS, FLUKA, HETC-HEDS, MCNPX_HI, and NUCFRG2
Sihver, L.*; Mancusi, D.*; Niita, Koji*; Sato, Tatsuhiko; Townsend, L.*; Farmer, C.*; Pinsky, L.*; Ferrari, A.*; Cerutti, F.*; Gomes, I.*
Acta Astronautica 63(7-10), p.865-877(2008) ; (JAEA-J 04455)

A reliable and accurate particle and heavy ion transport code is an essential implement in the design study of accelerator facilities as well as for other various applications such as, spallation neutron sources, rare isotopes production, and radiation protection. Today several particle and heavy ion MC transport codes exist, e.g. PHITS, HETC-HEDS, SHIELD-HIT, GEANT4, FLUKA, and MCNPX. In this paper, we present an extensive bench marking of the calculated projectile fragmentation cross sections from the reactions of 200-1000 MeV/n ⁴He, ¹²C, ⁴N, ⁶O, ²⁰Ne, ²⁸Si,⁴⁰Ar, and ⁵⁶Fe, which are relevant to space radioprotection, using PHITS, FLUKA, HETC-HEDS, and MCNPX_HI, against measurements performed by C. Zeitlin et al, at LBNL. The influence of the different models used in the different transport codes on the calculated results is discussed.

36001155
Active reduction of the end effect by local installation of neutron absorbers
Suyama, Kenya; Murazaki, Minoru; Okubo, Kiyoshi; Okuno, Hiroshi
Annals of Nuclear Energy 35(9), p.1628-1635(2008) ; (JAEA-J 04456)

In the analysis of the burnup credit, it has been pointed out that the neutron multiplication factor becomes greater if we consider an axial burnup distribution of spent fuel assemblies than the case under an assumption of an average burnup through the fuel assemblies. This phenomenon is called "end effect" and it is one of the main technical issues in the burnup credit study. In this study, the reason why the end effect occurs in the criticality calculation of spent fuel assemblies is discussed by analyses of neutron flux distribution measurement both fixed source and eigenvalue calculations. These calculations show us that the end effect is induced by the solution of neutron balance equation as eigenvalue problem and an actual neutron flux increase occurs only when the neutron multiplication factor is close to unity. Based on the discussion, reducing the end effect actively by local installation of neutron absorbers (LINA) around the end regions of the fuel assemblies are proposed and its effect was confirmed based on the several criticality calculations.

36001156
High-dome blisters formed by deuterium-induced local superplasticity
Shu, Wataru
Applied Physics Letters 92(21), p.211904_1-211904_3(2008) ; (JAEA-J 04457)

The high-dome blisters appearing on tungsten after deuterium plasma exposure at around 500K are considered to be generated by the diffusion and agglomeration of the deuterium-vacancy clusters, and this kind of deformation is called as deuterium-induced local superplasticity. There were cavities inside the blisters smaller than a few micrometers, whereas there were no hollow lids formed for some blisters greater than a few micrometers, which is contrary to the typical feature of blisters reported before.

36001157
Fitting of the modified Rutherford Equation; A Comparison bewteen ASDEX Upgrade and JT-60U results
Urso, L.*; Zohm, H.*; Fischer, R.*; Isayama, Akihiko; Kamada, Yutaka; ASDEX Upgrade Team; JT-60 Team
Europhysics Conference Abstracts (CD-ROM) 32F, 4p.(2008) ; (JAEA-J 04458)

36001158
Application of PLC to dynamic control system for liquid He cryogenic pumping facility on JT-60U NBI system
Honda, Atsushi; Okano, Fuminori; Oshima, Katsumi; Akino, Noboru; Kikuchi, Katsumi; Tanai, Yutaka; Takenouchi, Tadashi; Numazawa, Susumu*; Ikeda, Yoshitaka
Fusion Engineering and Design 83(2-3), p.276-279(2008) ; (JAEA-J 04459)

The control system of the cryogenic facility in the JT-60 NBI system has been renewed by employing the PLC (Programmable Logic Controller) and SCADA (Supervisory Control And Data Acquisition) system. The original control system was constructed about 20 years ago by specifying the DCS (Distributed Control System) computer to deal with 400 feedback loops. Recently, troubles on this control system have increased due to its aged deterioration. To maintain a high reliability of the cryogenic facility, a new control system has been intended with PLC and SCADA system. By optimizing the function blocks and connecting them in the FBD language, the feedback loops in the new control system have been successfully replaced from DCS to PLC without software developer. At present, the new control system has worked well. This is the first application of the marketable PLC to the actual system with feedback loops of > 400 produced by the user itself.

36001159
Design of a new P-NBI control system for 100-s injection in JT-60SA
Okano, Fuminori; Shinozaki, Shinichi; Honda, Atsushi; Oshima, Katsumi; Numazawa, Susumu*; Ikeda, Yoshitaka
Fusion Engineering and Design 83(2-3), p.280-282(2008) ; (JAEA-J 04460)

36001160
Tokamak machine monitoring and control system for JT-60
Miyo, Yasuhiko; Yagyu, Junichi; Nishiyama, Tomokazu; Honda, Masao; Ichige, Hisashi; Kaminaga, Atsushi; Sasajima, Tadayuki; Arai, Takashi; Sakasai, Akira
Fusion Engineering and Design 83(2-3), p.337-340(2008) ; (JAEA-J 04461)

36001161
ITER design review; Tritium issues
Murdoch, D.*; Beloglazov, S.*; Boucquey, P.*; Chung, H.*; Glugla, M.*; Hayashi, Takumi; Perevezentsev, A.*; Sessions, K.*; Taylor, C.*
Fusion Science and Technology 54(1), p.3-8(2008) ; (JAEA-J 04462)

One of the key activities on ITER during 2007 is a Design Review covering selected high priority areas of the project in which a significant number of features of the design with the potential to compromise the achievement of some objectives of ITER have been identified. These issues are being addressed by a number of focused working groups to develop solutions, which will improve the ITER design in terms of operating margins, reliability and availability, compliance with the French licensing framework and other respects. One of the working groups, WG-7, has been set up to investigate tritium related issues. The principal design features which are being addressed by WG-7 and the proposed resolutions of these issues are described in this paper, such as atmosphere and vent detritiation systems.

36001162
Tritium research activities under the Broader Approach program in JAEA
Yamanishi, Toshihiko; Hayashi, Takumi; Shu, Wataru; Kawamura, Yoshinori; Nakamura, Hirofumi; Iwai, Yasunori; Kobayashi, Kazuhiro; Isobe, Kanetsugu
Fusion Science and Technology 54(1), p.45-50(2008) ; (JAEA-J 04463)

The R&D for tritium technologies towards to the DEMO plants are carried out in Broader Approach (BA) program in Japan: (1) tritium accountancy technology; (2) basic tritium safety research; and (3) tritium durability test. A multi-purpose facility is constructed at Rokkasho in Japan to carry out the above R&Ds. Beta γ radioisotopes as well as tritium (370 TBq/year) can be handled in the facility. At TPL (Tritium Process Laboratory) of JAEA, a series of R&Ds for the tritium technologies relevant to the above BA program have been started. A series of basic studies for the tritium-materials has also been carried out. The main R&D activities in this field are the tritium behavior in a confinement; monitoring; detritiation; and decontamination. In this paper, the results of above recent activities at TPL of JAEA are also summarized from viewpoint of future fusion DEMO reactors.

36001163
Concentration profiles of tritium penetrated into concrete
Takata, Hiroki*; Furuichi, Kazuya*; Nishikawa, Masabumi*; Fukada, Satoshi*; Katayama, Kazunari*; Takeishi, Toshiharu*; Kobayashi, Kazuhiro; Hayashi, Takumi; Namba, Haruyuki*
Fusion Science and Technology 54(1), p.223-226(2008) ; (JAEA-J 04464)

Concentration profiles of tritium penetrated into cement paste, mortar and concrete were measured by using samples with a shape of column. Tritium penetrated until a location of about 5 cm from the exposed surface after 6 months' exposure. The amount of tritium penetrated into mortar and concrete were less than 70% and half that into cement paste.

36001164
Tritium behavior intentionally released in the room
Kobayashi, Kazuhiro; Hayashi, Takumi; Iwai, Yasunori; Yamanishi, Toshihiko; Willms, R. S.*; Carlson, R. V.*
Fusion Science and Technology 54(1), p.311-314(2008) ; (JAEA-J 04465)

In order to obtain the data for actual tritium behavior in the room and/or building, a series of intentional tritium release experiments were planed and carried out within a radiological controlled area at Tritium System Test Assembly (TSTA) in Los Alamos National Laboratory (LANL) under US-JAPAN collaboration program. In these experiments, influence of a difference of the release point and a difference of the amount of hydrogen isotope were suggested. In this report, the results of intentional tritium release experiments at TSTA in LANL are summarized. The released tritium was reached a uniform value about 30 ∼ 40 minutes in all the experiments. The influence of the difference of the release point and the difference of the amount of hydrogen isotope were not seen in these experiments drastically. The initial tritium behavior in the room is also discussed by comparing calculated values with experimental results.

36001165
Operational results of the safety systems of the tritium process laboratory of the Japan Atomic Energy Agency
Yamanishi, Toshihiko; Yamada, Masayuki; Suzuki, Takumi; Shu, Wataru; Kawamura, Yoshinori; Nakamura, Hirofumi; Iwai, Yasunori; Kobayashi, Kazuhiro; Isobe, Kanetsugu; Hoshi, Shuichi; Hayashi, Takumi
Fusion Science and Technology 54(1), p.315-318(2008) ; (JAEA-J 04466)

The construction of the building and safety systems of the TPL was completed until 1985. The operations of the safety systems with tritium have been started from March 1988. The amount of tritium held at the TPL was 13 PBq at March 2007. The average tritium concentration in a stream from a stack of the TPL to environment was 6.0×10^-3 Bq/cm³; and is 1/100 smaller than that of the regulation value for the concentration of HTO in the air in Japan. The safety operation results with tritium have thus been obtained. A set of failure data of several main components of the TPL was also obtained as the valuable data for fusion tritium facilities.

36001166
Tritium safety study using caisson assembly (CATS) at TPL/JAEA
Hayashi, Takumi; Kobayashi, Kazuhiro; Iwai, Yasunori; Isobe, Kanetsugu; Nakamura, Hirofumi; Kawamura, Yoshinori; Shu, Wataru; Suzuki, Takumi; Yamada, Masayuki; Yamanishi, Toshihiko
Fusion Science and Technology 54(1), p.319-322(2008) ; (JAEA-J 04467)

Tritium confinement is required as the most important safety function for a fusion reactor. In order to demonstrate the confinement performance experimentally, an unique equipment, called CATS: Caisson Assembly for Tritium Safety study, was installed in Tritium Process Laboratory of Japan Atomic Energy Agency and operated for about 10 years. Tritium confinement and migration data in CATS have been accumulated and dynamic simulation code was developed using these data. Contamination and decontamination behavior on various materials and new safety equipment functions have been investigated under collaborations with a lot of laboratories and universities. In this paper, these accomplishments are summarized and future plan are discussed.

36001167
Research program on tritium control methods in supercritical CO₂ gas-cooled reactors
Nakamura, Hirofumi; Isobe, Kanetsugu; Nakamichi, Masaru
Fusion Science and Technology 54(2), p.341-345(2008) ; (JAEA-J 04468)

Super critical carbon dioxide (SCCO₂) cooled reactor is attractive because of its higher thermal efficiency and low reactivity with the primary coolant. But, tritium permeation from primary coolant to the secondary coolant (SCCO₂) through the heat exchanger tubes will increase in this system, it is important to control tritium in the secondary coolant. JAEA has been investigated a research on the tritium control method in the SCCO₂ cooling reactor. This program consists of two activities; those are development of the tritium permeation reduction coating through the heat exchanger tubes and development of tritium removal method from the SCCO₂. As to the permeation reduction, the glassy coating developed by JAEA as the tritium permeation reduction barrier for the water cooled fusion reactors are applied to the SCCO₂ cooling system. As a result of experiment, physical and chemical stability of the coating under 100 hours soaking in the SCCO₂ has been demonstrated. As to the tritium control in the coolant, it is essential to identify the chemical state of tritium in the SCCO₂ in order to remove tritium from the SCCO₂ system. In this viewpoint, self-radio chemical reaction study between tritium and CO₂ has been initiated. Based on these results, effective tritium control method in the SCCO₂ system will be proposed. In the presentation, detail of this program and experimental results will be reported.

36001168
Dynamic behavior of chemical exchange column in a water detritiation system for a fusion reactor
Yamanishi, Toshihiko; Iwai, Yasunori
Fusion Science and Technology 54(2), p.454-457(2008) ; (JAEA-J 04469)

In a fusion reactor, a large amount of tritiated water is expected to be produced. A CECE (Combined Electrolysis Catalytic Exchange) column is applied to process this water. The CECE column of a water processing system of a demo fusion plant design by JAEA is chosen for a reference case. The height and inner diameter of the columns are 22 and 0.7 m. A main feed stream to the column is 20 kg/h, and its atomic ratio of tritium is 5.0×10^-5. We have developed a simulation code of the CECE column, and have analyzed its dynamic characteristics. In the case where the column is filled with natural water, it takes about 3 hours to reach the steady state of the column. If the column has the recombiner, only a hour is needed to reach the steady state after the total reflux operation. The effect of the reflux has thus been indicated. The control characteristics of the CECE column are also reported by using the developed code with a series of calculated results.

36001169
Solid-polymer-electrolyte tritiated water electrolyzer for water detritiation system
Iwai, Yasunori; Yamanishi, Toshihiko; Hiroki, Akihiro; Yagi, Toshiaki*; Tamada, Masao
Fusion Science and Technology 54(2), p.458-461(2008) ; (JAEA-J 04470)

A solid-polymer-electrolyte (SPE) water electrolyzer for high-level tritiated water was designed for the Water Detritiation System (WDS). Polymeric materials were selected from a main viewpoint of radiation durability to keep their functions beyond ITER-WDS requirement (530 kGy). Our selection was Pt + Ir applied Nafion N117 ion exchange membrane, VITON O-ring seal and polyimide insulator. A g-ray irradiation test of the SPE cell demonstrated the durability of the cell against 530 kGy. The detritiation of the polymeric materials is a critical problem for the maintenance or for the disposal of the electrolyzer. As for the Nafion membrane, most of tritiated water in the membrane was rapidly removed by such as vacuum dehydration. It was difficult, by contrast, to remove bound tritiated water in the membrane. An effective method to remove tritiated water in the bound water is to promote an isotope exchange.

36001170
Effect of cation on HTO/H₂O separation and dehydration characteristics of Y-type zeolite adsorbent
Iwai, Yasunori; Uzawa, Masayuki*; Yamanishi, Toshihiko
Fusion Science and Technology 54(2), p.462-465(2008) ; (JAEA-J 04471)

Adsorber has been studied to apply in the first stage of water detritiation system processing more than 100 kg/h of high-level tritiated water generated in a future fusion plant. Zeolite is a suitable adsorbent since it is an inorganic matter having a large water capacity. Rapid dehydration characteristic as well as large HTO/H₂O separation factor is necessary for adsorber to minimize its size. Present experiments were focused on the effect of cation on HTO/H₂O separation and dehydration characteristics of Y-type zeolites. It was found that the isotope separation factors are around 1.1-1.2 under static conditions. As for dehydration, operating temperature fixs the movable water capacity of the zeolites and the capacity at room temperature is NaY > CaY > KY. HTO dehydration characteristics depend on the accumulated purge gas amount and the purge gas rate is less influential. It is found that pressure swing is an effective method for HTO dehydration.

36001171
Observation of tritium distribution in iron oxide with tritium micro autoradiography
Isobe, Kanetsugu; Hayashi, Takumi; Nakamura, Hirofumi; Kobayashi, Kazuhiro; Yamanishi, Toshihiko; Okuno, Kenji*
Fusion Science and Technology 54(2), p.533-536(2008) ; (JAEA-J 04472)

Tritium permeation is one of key issues from the viewpoint of safety and tritium cycle. The oxide formed on metal surface was reported to act as barrier for hydrogen permeation due to its characters, such as low diffusivity and low solubility of hydrogen. On the other hand, the tritium behavior in the oxide as well as the interface of oxide (oxide-metal, oxide-water) is not clarified. The tritium permeation through pure iron, which was coated with its oxide, into water has been studied. Although some characteristics of tritium permeation through the oxide were found, the permeation mechanism through the oxide has not been clarified yet. The tritium distribution in the oxide can give us useful information of tritium behavior in the oxide / oxide-interface and help to understand the mechanism of tritium permeation through the oxide. In the present study, tritium distribution in the iron oxide is observed with tritium micro autoradiography.

36001172
New oriented-molecular-beam machine for surface stereochemistry with X-ray photoemission spectroscopy
Okada, Michio*; Hashinokuchi, Michihiro*; Moritani, Kosuke*; Kasai, Toshio*; Teraoka, Yuden
Japanese Journal of Applied Physics 47(5), p.3686-3691(2008) ; (JAEA-J 04473)

An oriented-molecular-beam technique based on the Stark effect of a molecule in an inhomogeneous hexapole electrostatic field is a potential tool for stereochemical control of surface reactions. This technique allows us to select a specific rotational quantum state and also an orientation of a reagent molecule. We have developed a new UHV-compatible oriented-molecular-beam machine. This apparatus is equipped with components for X-ray photoemission spectroscopy (XPS) in order to detect surface-reaction products. In the dissociative adsorption of NO on an Si(111) surface, we found a steric effect in the reactivity by monitoring the products on the surface with the new machine. The N-end collision is more reactive than the O-end collision at an incident energy of 58 meV. To our knowledge, this is the first measurement of the steric effect appearing in the reaction products on the surface.

36001173
Bandwidth enhancement of optical parametric chirped pulse amplification by temporally delayed two pump beams
Ogawa, Kanade; Aoyama, Makoto; Akahane, Yutaka; Tsuji, Koichi; Kawanaka, Junji*; Harimoto, Tetsuo*; Nishioka, Hajime*; Fujita, Masayuki*; Yamakawa, Koichi
Japanese Journal of Applied Physics 47(6), p.4592-4594(2008) ; (JAEA-J 04474)

We have demonstrated ultra-broadband optical parametric chirped-pulse amplification of more than 350 nm bandwidth in a near infrared region. We have observed a substantial enhancement (nearly 2-fold) of the parametric amplification bandwidth by using time delayed two broadband pump pulses at degeneracy.

36001174
In situ determination of Sb distribution in Sb/GaAs(001) layer for high-density InAs quantum dot growth
Kaizu, Toshiyuki*; Takahashi, Masamitsu; Yamaguchi, Koichi*; Mizuki, Junichiro
Journal of Crystal Growth 310(15), p.3436-3439(2008) ; (JAEA-J 04475)

An Sb-adsorbed GaAs(001) substrate that serves as a template for high-density InAs quantum dot (QD)growth was investigated using in situ X-ray diffraction. The Sb distribution in the top eight layers from the surface was determined by crystal truncation rod scattering analysis. It was found that Sb atoms penetrated to the eighth layer when GaAs(001) came in contact with an Sb environment. The amounts of Sb in the first and second layers were, however, saturated at 1/3 atomic layer (AL) and 2/3 AL, respectively. A comparison between the X-ray results and atomic force microscopy observations of the QD density showed that the formation of high-density QDs is correlated with the total amount of Sb in the surface and subsurface layers.

36001175
Radiation deterioration in mechanical properties and ion exchange capacity of Nafion N117 swelling in water
Iwai, Yasunori; Hiroki, Akihiro; Tamada, Masao; Yamanishi, Toshihiko
Journal of Membrane Science 322(1), p.249-255(2008) ; (JAEA-J 04476)

Soaking Nafion N117 in oxygen-saturated distilled water was irradiated by g-rays or electron beam at various dose ranging to 1600 kGy at room temperature or 343K to obtain detailed information on the effect of oxygen on radiation deterioration in Nafion mechanical properties and ion exchange capacity. The contribution of reactions that boar no relation to oxygen to radiation deterioration in mechanical property was dominant for the irradiation in oxygen-saturated distilled water at room temperature. The effect of oxygen was not significant due to little oxygen concentration in distilled water. Irradiated Nafion N117 became a weak and brittle material at 343K. The effect of oxygen became negligible at 343K. The ion exchange capacity irradiated at the dose of 1600kGy was only 20% decrease of initial capacity at room temperature.

36001176
Corrosion rate of parent and weld materials of F82H and JPCA steels under LBE flow with active oxygen control at 450 and 500 °C
Kikuchi, Kenji; Kamata, Kinya*; Ono, Mikinori*; Kitano, Teruaki*; Hayashi, Kenichi*; Oigawa, Hiroyuki
Journal of Nuclear Materials 377(1), p.232-242(2008) ; (JAEA-J 04477)

Corrosion behavior of F82H and JPCA was studied in the circulating LBE loop. Those are candidate materials of Japanese ADS beam windows. Maximum temperatures were kept to 450 and 500 °C with 100 °C constant temperature difference. Main flow velocity was 0.4 to 0.6 m/s in every case. Oxygen concentration was controlled to 2∼4×10^-5 mass% although there was an exception. Testing time durations were 500 to 3000 hrs. Round bar type specimens were put in the circular tube of the loop. Electron beam welded joint in the middle part of specimens were also studied. Optical micrograph, electron micrograph, X-ray element analyses and X-ray diffraction were investigated. Consequently for a long-term behavior a linear law is recommended to predict corrosion in the ADS beam design.

36001177
Effects of locally targeted heavy-ion and laser microbeam on root hydrotropism in Arabidopsis thaliana
Miyazawa, Yutaka*; Sakashita, Tetsuya; Funayama, Tomoo; Hamada, Nobuyuki*; Negishi, Hiroshi*; Kobayashi, Akie*; Kaneyasu, Tomoko*; Oba, Atsushi*; Morohashi, Keita*; Kakizaki, Takehiko*; Wada, Seiichi*; Kobayashi, Yasuhiko; Fujii, Nobuharu*; Takahashi, Hideyuki*
Journal of Radiation Research 49(4), p.373-379(2008) ; (JAEA-J 04478)

We examined the role of root cap and elongation zone cells in root hydrotropism using heavy-ion and laser microbeam. Heavy-ion microbeam irradiation of the elongation zone, but not that of the columella cells, significantly and temporary suppressed the development of hydrotropic curvature. However, laser ablation confirmed that columella cells are indispensable for hydrotropism. Systemic heavy-ion broad-beam irradiation suppressed de novo expression of INDOLE ACETIC ACID 5 gene, but not MIZU-KUSSEI1 gene. Our results indicate that both the root cap and elongation zone have indispensable and functionally distinct roles in root hydrotropism, and that de novo gene expression might be required for hydrotropism in the elongation zone, but not in columella cells.

36001178
Safety cases for the deep disposal of radioactive waste; Where do we stand?
Forinash, B.*; Pescatore, C.*; Umeki, Hiroyuki
NEA News 25(1), p.16-17(2007) ; (JAEA-J 04479)

Central to successfully implementing long-term deep disposal of radioactive waste is the ability to evaluate and illustrate the safety of a disposal system after closure and far into the future in a manner that is clear, scientifically sound, and persuasive to decision-makers and the public. A recent NEA symposium on "Safety Cases for the Deep Disposal of Radioactive Waste: Where do we stand?" reviewed progress and practical experiences at both the technical and managerial level in preparing for and developing safety cases. The meeting showed that safety cases have evolved into tools to both evaluate and illustrate safety, and to aid in decision-making. Important work continues on the topic.

36001179
Steady-state operation of 170 GHz-1 MW gyrotron for ITER
Kasugai, Atsushi; Sakamoto, Keishi; Takahashi, Koji; Kajiwara, Ken; Kobayashi, Noriyuki
Nuclear Fusion 48(5), p.054009_1-054009_6(2008) ; (JAEA-J 04480)

A 170 GHz gyrotron has been developed at JAEA, which has achieved operation of 1 MW/800 s and up to 55% efficiency. This is the first demonstration of a gyrotron achieving and even exceeding the ITER operating requirements of 1 MW/500 s and 50% efficiency. In addition the gyrotron demonstrated operation for 1 hour with the output power of 0.6 MW. The oscillation was stable with all cooling water temperatures and vacuum pressure reaching equilibrium conditions during the pulse length at either power levels. The successful operation was aided by very low level of stray radiation (2% of the output power), and contributed to the fast conditioning and the stable operation. The output power from the gyrotron was coupled into an ITER sized corrugated waveguide (Dia.= 63.5 mm) via a matching optics unit with a total of 0.97 MW transmitted to the dummy load after two miter bends and 7 m of waveguide without any trouble. These results give an encouraging outlook for the success of ITER electron cyclotron heating and current drive system.

36001180
Numerical analysis of the effect of fast-ion losses on plasma rotation in a tokamak with toroidal field ripple
Honda, Mitsuru; Takizuka, Tomonori; Fukuyama, Atsushi*; Yoshida, Maiko; Ozeki, Takahisa
Nuclear Fusion 48(8), p.085003_1-085003_12(2008) ; (JAEA-J 04481)

The effect of fast-ion losses due to the toroidal field ripple on the toroidal rotation is studied through numerical simulations. The simulations are carried out by utilizing a multi-fluid one-dimensional transport code, TASK/TX, with ripple transport model suitable for implementing one-dimensional transport codes. Simulation results are qualitatively consistent with the experiments in JT-60U. It is shown that the return current associated with the outward radial fast-ion current due to the ripple loss flows inward in the bulk plasma and the resultant j×B torque drives the plasma toroidally in the counter direction of the plasma current. The equilibrium value of the toroidal rotation velocity is determined by the balance between the perpendicular viscosity and the total torque.

36001181
Cavitation damage reduction by microbubble injection
Naoe, Takashi; Ida, Masato; Futakawa, Masatoshi
Nuclear Instruments and Methods in Physics Research A 586(3), p.382-386(2008) ; (JAEA-J 04482)

A series of experiments on cavitation caused by mechanically induced pressure pulses has been performed to provide experimental evidence that gas microbubbles injected into a liquid can reduce cavitation damage. The working fluid of the present study is liquid mercury as in spallation neutron sources to produce high-intensity neutron beams, and the experiments were conducted under three different flow conditions: single-phase static, single-phase flow, and bubbly flow conditions. The experiments suggested that compared to the static case, cavitation damage is reduced by flowing the mercury, and further remarkably reduced by injecting microbubbles into the mercury flow. A slight decrease of the magnitude of negative pressure found in the bubbly flow case appears to be a key to understanding the mechanism of the observed cavitation damage reduction.

36001182
A Study of air ingress and its prevention in HTGR
Yan, X.; Takeda, Tetsuaki; Nishihara, Tetsuo; Ohashi, Kazutaka; Kunitomi, Kazuhiko; Tsuji, Nobumasa*
Nuclear Technology 163(3), p.401-415(2008) ; (JAEA-J 04483)

A rupture of primary piping in HTGR represents a design basis event. In such a loss of coolant event a safety issue remains graphite oxidation damage to fuel and core should major air ingress take place through the breached primary boundary. The present study deals with the two most probable cases of air ingress. The first results from rupture of a standpipe. A design change proposed in the vessel top structure intends to rule out any probability of a standpipe rupture. The feasibility of the modified structure is evaluated. The second case results from rupture of a main coolant pipe. Experiment and analysis are performed to gain understanding of the multi-phased air ingress phenomena and accordingly a new mechanism of sustained counter-air diffusion is proposed that is fully passive and effective in preventing major air ingress in the event of main coolant pipe rupture. The results of the present study may lead to improved safety and economic design of the HTGR.

36001183
Loop effects in the Ising spin glass on the Bethe-like lattices
Yokota, Terufumi
Physica A 387(14), p.3495-3502(2008) ; (JAEA-J 04484)

Equations for the spin glass order in the Ising spin glass model on the Bethe-like lattices with and without small loops are studied. For each lattice, equations are obtained by using and not using the replica method. Within the replica symmetric approximation, equations obtained by the two ways are shown to be identical. To see the effects of the small loops and the replica symmetry breaking, a spin glass order parameter is investigated as a function of the connectivity of the lattices close to the transition temperature. Replica symmetry breaking is enhanced by the existence of small loops.

36001184
Dual-harmonic auto voltage control for the rapid cycling synchrotron of the Japan Proton Accelerator Research Complex
Tamura, Fumihiko; Schnase, A.; Yoshii, Masahito*
Physical Review Special Topics; Accelerators and Beams 11(7), p.072001_1-072001_9(2008) ; (JAEA-J 04485)

The dual-harmonic operation, in which the accelerating cavities are driven by the superposition of the fundamental and the second harmonic rf voltage, is useful for acceleration of the ultrahigh intensity proton beam in the rapid cycling synchrotron (RCS) of Japan Proton Accelerator Research Complex (J-PARC). However, the precise and fast voltage control of the harmonics is necessary to realize the dual-harmonic acceleration. We developed the dual-harmonic auto voltage control system for the J-PARC RCS. We describe details of the design and the implementation. Various tests of the system are performed with the RCS rf system. Also, a preliminary beam test has been done. We report the test results.

36001185
Plasma physics and radiation hydrodynamics in developing an extreme ultraviolet light source for lithography
Nishihara, Katsunobu*; Sunahara, Atsushi*; Sasaki, Akira; Nunami, Masanori*; Tanuma, Hajime*; Fujioka, Shinsuke*; Shimada, Yoshinori*; Fujima, Kazumi*; Furukawa, Hiroyuki*; Kato, Takako*; Koike, Fumihiro*; More, R.*; Murakami, Masakatsu*; Nishikawa, Takeshi*; Zhakhovskii, V.*; Gamata, Kohei*; Takata, Akira*; Ueda, Hirofumi*; Nishimura, Hiroaki*; Izawa, Yasukazu*; Miyanaga, Noriaki*; Mima, Kunioki*
Physics of Plasmas 15(5), p.056708_1-056708_11(2008) ; (JAEA-J 04486)

Extreme ultraviolet (EUV) radiation from laser-produced plasma (LPP) has been thoroughly studied for application in mass-production of the next generation semiconductor devices. One critical issue for realization of a LPP-EUV light source for lithography is the conversion efficiency (CE) from incident laser power to EUV radiation of 13.5 nm wavelength (within 2% bandwidth). Another is solving a problem of damage caused by debris reaching a EUV collecting mirror. We here present an improved power balance model, which can be used for the optimization of laser and target conditions to obtain high CE. An integrated numerical simulation code has been developed for target design. The code is shown to agree well with experimental results not only for the CE but also for detailed EUV spectral structure. We propose a two pulse irradiation scheme for high CE and reduced ion debris using a carbon dioxides laser and a droplet or punch-out target.

36001186
Use of positron-emitting tracer imaging system for measuring the effect of salinity on temporal and spatial distribution of ¹¹C tracer and coupling between source and sink organs
Suwa, Ryuichi*; Fujimaki, Shu; Suzui, Nobuo; Kawachi, Naoki; Ishii, Satomi; Sakamoto, Koichi*; Nguyen, N. T.*; Saneoka, Hirofumi*; Mohapatra, P. K.*; Moghaieb, R. E.*; Matsuhashi, Shimpei; Fujita, Konosuke*
Plant Science 175(3), p.210-216(2008) ; (JAEA-J 04487)

Salinity stress affects photosynthate partitioning between sources and sinks of plants, but how it affects on these systems is less understood. Because sources and sinks are closely knitted, any adverse effect under sub-optimal condition on one part is often misinterpreted for the other. Knowledge on regulation of carbon partitioning is indispensable for stress resistance and good plant growth. In the present study, alteration of carbon partitioning in tomato plants (lycopersicon esculentum L. cv. Momotarou) under saline (NaCl) environment was studied by feeding radioactive ¹¹C and stable ¹³C isotopes. Pulse chases were conducted for measuring spatial and temporal distributions of ¹³C. ¹³C was measured by standard conventional technique, but ¹¹C distribution was monitored using by PETIS. Salt stress resulted in reduced carbon translocation towards roots. Majority of the photosynthate accumulated in the leaf. We have also observed that the reduction in translocation of carbon occurred well before salt stress symptoms of reduced photosynthesis and plant growth in salt exposed plants. The effect on sink activity also showed by decrease in stem diameter and reduced photosynthetic activity. In addition, PETIS analysis of ¹¹C translocation indicates that carbon translocation to roots was inhibited under salt conditions without direct effect of leaf Na accumulation and osmotic stress These results suggest that NaCl has direct effects on plants inhibiting carbon partitioning within few hours of salt solution exposure without inhibition of source activity.

36001187
Optimization of extreme ultraviolet emission from laser-produced tin plasmas based on radiation hydrodynamics simulations
Sunahara, Atsushi*; Nishihara, Katsunobu*; Sasaki, Akira
Plasma and Fusion Research (Internet) 3, p.043_1-043_5(2008) ; (JAEA-J 04488)

36001188
Catalytic oxidation of xylene in air using TiO₂ under electron beam irradiation
Hakoda, Teruyuki; Matsumoto, Kanae; Mizuno, Akira*; Kojima, Takuji; Hirota, Koichi
Plasma Chemistry and Plasma Processing 28(1), p.25-37(2008) ; (JAEA-J 04489)

The oxidation of xylene and its irradiation byproducts in air using TiO₂ was studied under electron beam (EB) irradiation for the purification of ventilation gases emitted from paint factories. EB irradiation experiments were performed mainly under two different conditions: a TiO₂ pellet layer was placed in an irradiation or non-irradiation space. The results revealed that xylene was decomposed and CO was formed in the gas phase of the irradiation space irrespective of the presence of the TiO₂ pellets, while CO₂ was produced in the gas phase of the irradiation space and on the surface of the TiO₂ pellets. The total CO₂ concentration increased when the pellet layer was in the non-irradiation space. On the other hand, the concentration of CO₂ produced on the surface of the TiO₂ pellets in the irradiation space was higher than that in a non-irradiation space.

36001189
Transparency and nonproliferation in the Asia-Pacific region; Enhancing transparency, strengthening the nonproliferation regime
Hamada, Kazuko
Progress in Nuclear Energy 50(2-6), p.660-665(2008) ; (JAEA-J 04490)

The Asia-Pacific region is destined to increase its use of nuclear energy in the coming decades. This projected increase will bring with it nuclear proliferation concerns, and thus, necessitates supplementary efforts designed to ensure nuclear security and a legitimate use of nuclear energy in addition to the NPT obligation. Nuclear transparency measures could be useful tools to build confidence that the increasing use of nuclear energy does not contribute to nuclear proliferation. These measures could also foster a cooperative tradition that can address rising concerns over nuclear trafficking and terrorism, which require regional coordination to combat. This paper describes various forms of potential transparency measures to expand the possibilities of the nuclear transparency concept and explore areas in which this concept might be applicable. This paper also clarifies some of the challenges involving transparency projects and suggests possible ways to address these challenges.

36001190
Influence of grafting solvents on the properties of polymer electrolyte membranes prepared by γ-ray preirradiation method
Kimura, Yosuke; Asano, Masaharu; Chen, J.; Maekawa, Yasunari; Katakai, Ryoichi*; Yoshida, Masaru
Radiation Physics and Chemistry 77(7), p.864-870(2008) ; (JAEA-J 04491)

We prepared polymer electrolyte membranes (PEMs) by post-polymerization of styrene (St) with divinylbenzene (DVB) into poly(ethylene-co-tetrafluoroethylene) (ETFE) films in the presence of toluene, isopropyl alcohol (iPrOH), tetrahydrofuran (THF), and tetrachloroethane (TCE) after pre-γ-irradiation followed by a sulfonation. In the case of iPrOH, the grafting yield showed a marked increase compared with those of other solvents. On the other hand, it was found that the durability time of a PEM prepared in the presence of tetrachloroethane was 2 times higher than that in the presence of toluene.

36001191
Spectroscopic observations of beam and source plasma light and testing Cs-deposition monitor in the large area negative ion source for LHD-NBI
Oka, Yoshihide*; Tsumori, Katsuyoshi*; Ikeda, Katsunori*; Kaneko, Osamu*; Nagaoka, Kenichi*; Osakabe, Masaki*; Takeiri, Yasuhiko*; Asano, Eiji*; Komada, Seiji*; Kondo, Tomoki*; Sato, Mamoru*; Shibuya, Masayuki*; Grisham, L. R.*; Ikeda, Yoshitaka; Hanada, Masaya; Umeda, Naotaka
Review of Scientific Instruments 79(2), p.02C105_1-02C105_4(2008) ; (JAEA-J 04492)

In the present studies, we studied the cesium lines in the source plasma during beam shots on the LND MN-NBI system. It was found for the first time in the LHD-source 2, that both the amount of Cs I (neutral Cs) and Cs II (Cs⁺) in the source plasma light rose sharply when beam acceleration began, and continued rising during a 10 s pulse. We think that this was because the cesium was evaporated/sputtered from the source backplate by the back-streaming positive ions.

36001192
Beamlet deflection due to beamlet-beamlet interaction in a large-area multiaperture negative ion source for JT-60U
Kamada, Masaki; Hanada, Masaya; Ikeda, Yoshitaka; Grisham, L. R.*; Jiang, W.*
Review of Scientific Instruments 79(2), p.02C114_1-02C114_3(2008) ; (JAEA-J 04493)

36001193
Long pulse production of high current D^- ion beams in the JT-60 negative ion source
Hanada, Masaya; Kamada, Masaki; Akino, Noboru; Ebisawa, Noboru; Honda, Atsushi; Kawai, Mikito; Kazawa, Minoru; Kikuchi, Katsumi; Komata, Masao; Mogaki, Kazuhiko; Noto, Katsuya; Oshima, Katsumi; Takenouchi, Tadashi; Tanai, Yutaka; Usui, Katsutomi; Yamazaki, Haruyuki; Ikeda, Yoshitaka; Grisham, L. R.*
Review of Scientific Instruments 79(2), p.02A519_1-02A519_4(2008) ; (JAEA-J 04494)

A long pulse production of high-current, high-energy D^- ion beams was studied in the JT-60U negative ion source that was designed to produce 22 A, 500 keV D^- ion beams. Prior to the long pulse production, the short pulse beams were produced to examine operational ranges for a stable voltage holding capability and an allowable grid power loading. From a correlation between the voltage holding capability and a light intensity of cathodoluminescence from the insulator made of Fiber Reinforced Plastic insulator, the voltage holding was found to be stable at < 340 kV where the light was sufficiently suppressed. The grid power loading for the long pulse operation was also decreased to the allowable level of < 1 MW without a significant reduction of the beam power by tuning the extraction voltage (Vext) and the arc power (Parc). These allow the production of 30 A D^- ion beams at 340 keV from two ion sources at Vacc = 340 kV. The pulse length was extended step by step, and finally reached up to 21 s, where the beam pulse length was limited by the surface temperature of the beam scraper without water cooling. The D^- ion beams were neutralized to via a gas cell, resulting in a long pulse injection of 3.2 MW D⁰ beams for 21 s. This is the first long injection of > 20 s in a power range of > 3 MW.

36001194
Surface discharge related properties of fiberglass reinforced plastic insulator for use in neutral beam injector of JT-60U
Yamano, Yasushi*; Takahashi, Masahiro*; Kobayashi, Shinichi*; Hanada, Masaya; Ikeda, Yoshitaka
Review of Scientific Instruments 79(2), p.02A524_1-02A524_4(2008) ; (JAEA-J 04495)

The JT-60U negative-ion-based NBI was designed to have 3-stage electrostatic accelerators with total accelerating voltage of 500kV. In order to hold such high voltage, three Fiberglass Reinforced Plastic (FRP) insulators of 1.8 m inner diameter and 31.5 cm height are used. Currently the hold-off voltage capability of 3-stage FRP insulators has been typically limited to < 460 kV without beam acceleration. One of the possible reason is a surface discharges on the FRP insulators. This paper describes measurement results of surface resistivity and volume resistivity under vacuum and atmospheric conditions, secondary electron emission (SEE) characteristics and cathodoluminescence under some keV electron beam irradiation, gas analysis desorbed from the FRP insulator under irradiation of some keV-electron beam were also analyzed.

36001195
Development and application of positron microprobe
Maekawa, Masaki; Kawasuso, Atsuo; Hirade, Tetsuya; Miwa, Yukio
Transactions of the Materials Research Society of Japan 33(2), p.287-290(2008) ; (JAEA-J 04496)

We present the development and application of a positron microprobe. Positrons from a small positron source developed by us were moderated by a solid neon moderator, and were focused onto the specimen using the optics of conventional scanning electron microscope (SEM). At present stage, the beam diameter was determined by scanning the beam across a knife-edge, and was found to be about 3.9 micrometer. Two dimensional scanning measurement of a cracked sample (stress-corrosion cracking) was performed. In the region distant from the tip of a crack, increase of S-parameter was found, which are possibly associated with the vacancy defects.

36001196
Solution property of low molar mass Konjac mannan
Makabe, Takeshi*; Prawitwong, P.*; Takahashi, Ryo*; Takigami, Machiko*; Nagasawa, Naotsugu; Takigami, Shoji*
Transactions of the Materials Research Society of Japan 33(2), p.471-474(2008) ; (JAEA-J 04497)

Konjac mannan (KM) is a water soluble glucomannan with high molar mass. KM aqueous solution shows extremely high viscosity. The effects of γ-rays irradiation and acid hydrolysis on molar mass were studied. The hydrolysis was carried out using citric acid. Characteristics of the irradiated and hydrolyzed KM were investigated using GPC-MALLS and a viscometer. The chemical structure of KM scarcely changed by both treatments. Molar mass of the irradiated KM decreased gradually with increasing dose. Molar mass of the hydrolyzed KM also decreased gradually with acid concentration. The viscosity of both treated KM aqueous solutions decreased with decreasing molar mass. High molar mass KM solution showed pseudo-plastic fluids behavior of the non-Newtonian fluid at dilute region and changed to Newtonian fluid with decrease of molar mass. Low molar mass KM solution showed behavior of Newtonian fluid at semi-dilute region. The critical concentration at the overlap limit of KM solution increased with decreasing of molar mass.

36001197
Applications of heavy-ion microbeams in biological studies (in Japanese)
Kobayashi, Yasuhiko; Funayama, Tomoo; Hamada, Nobuyuki*; Sakashita, Tetsuya; Yokota, Yuichiro; Fukamoto, Kana; Suzuki, Michiyo; Taguchi, Mitsumasa
Hoshasen Seibutsu Kenkyu 43(2), p.150-169(2008) ; (JAEA-J 04498)

36001198
The Mystery behind the extraordinary radioresistance of Deinococcus radiodurans (in Japanese)
Oba, Hirofumi; Sato, Katsuya; Narumi, Issei
Hoshasen To Sangyo (118), p.50-53(2008) ; (JAEA-J 04499)

36001199
Development of time-resolved X-ray fluorescence spectroscopy system using an X-ray tube driven by ultrafast pulsed laser (in Japanese)
Yamada, Hidetaka; Murakami, Hiroshi; Shimada, Yukihiro
Hyomen Kagaku 29(7), p.413-417(2008) ; (JAEA-J 04500)

A femtosecond-laser-driven X-ray source and an X-ray focusing system have been developed for the time-resolved X-ray fluorescence spectroscopy. The X-ray source, in which a plasma cathode induced by a 10¹³-W/cm² laser pulse serves as an electron source of an X-ray tube, provides 10⁹ Cu K_α photons in 4πsr per pulse. The X-ray pulse duration is measured to be about two hundred nanoseconds. Emission analysis of the plasma cathode indicates that the temporal characteristics of the X-ray pulse are determined by the dynamics of the plasma particles under the electrostatic shielding against the applied voltage in the X-ray tube. As for the X-ray focusing system, a focal spot size by a polycapillary lens is measured and the enhancement of X-ray fluorescence intensity due to the lens is demonstrated.

36001200
Toolbar to highlight important expressions in scientific articles on atomic and molecular physics
Murata, Masaki*; Sasaki, Akira; Kanamaru, Toshiyuki*; Shirado, Tamotsu*; Isahara, Hitoshi*
Jinko Chino Gakkai Rombunshi 23(6), p.457-462(2008) ; (JAEA-J 04501)

We introduce software that recognizes, extracts, and displays expressions concerning atomic and molecular data from academic papers in the electronic form. This software includes a toolbar application that can be installed in Internet Explorer (IE). This toolbar can be used by scientific readers and researchers to highlight, color-code, and collect important expressions more easily. Those expressions include atomic and molecular symbols and electron configurations from the atomic and molecular data of a large number of academic papers. We confirmed by experiments that the software could find important expressions with high precision. This software is also useful for compiling databases of atomic and molecular data, which is important for plasma simulations, because the simulations critically depend on atomic and molecular data, including the energy levels and collisional and radiative rate coefficients.

36001201
R&D for tritium removal system using bacteria for safety enhancement of tritium handling in fusion reactor (in Japanese)
Hayashi, Takumi; Kobayashi, Kazuhiro; Yamanishi, Toshihiko; Ichimasa, Yusuke*; Ichimasa, Michiko*
Karyoku Genshiryoku Hatsuden 59(4), p.316-321(2008) ; (JAEA-J 04502)

In order to enhance safety of fusion reactor, JAEA investigates effective tritium removal system in case of incidental tritium release in the building. Recently, we paid attention to the bacteria, which had an ability of hydrogen oxidation at room temperature, and a new effective detritiation system using the bacteria has been studied under the collaboration with Ibaraki University, instead of catalytic oxidation reactor of rare metal.

36001202
Extraction separation and nanoparticulation of gold ion from model industrial waste (in Japanese)
Shimojo, Kojiro
Kemikaru Enjiniyaringu 53(7), p.536-540(2008) ; (JAEA-J 04503)

36001203
What is really happening between the plasma edge and the wall?, 1; Physics modeling (in Japanese)
Hatayama, Akiyoshi*; Takizuka, Tomonori
Nippon Genshiryoku Gakkai-Shi 50(6), p.380-382(2008) ; (JAEA-J 04505)

36001204
Fusion research and development in the ITER, 1 (in Japanese)
Ninomiya, Hiromasa; Kubo, Hirotaka; Akiba, Masato
Nippon Genshiryoku Gakkai-Shi 50(7), p.426-433(2008) ; (JAEA-J 04506)

36001205
What is really happening between the plasma edge and the wall?, 2; Defence from the plasma attack (in Japanese)
Hatayama, Akiyoshi*; Takizuka, Tomonori
Nippon Genshiryoku Gakkai-Shi 50(7), p.443-447(2008) ; (JAEA-J 04507)

36001206
Fusion research and development in the ITER era, 2 (in Japanese)
Ninomiya, Hiromasa; Kubo, Hirotaka; Akiba, Masato
Nippon Genshiryoku Gakkai-Shi 50(8), p.500-505(2008) ; (JAEA-J 04508)

36001207
Experimental study on feasibility of capacitance void fraction meters (in Japanese)
Watanabe, Hironori; Mitsutake, Toru*; Kakizaki, Sadayuki*; Takase, Kazuyuki
Nippon Kikai Gakkai Rombunshu, B 74(742), p.1257-1262(2008) ; (JAEA-J 04509)

The electro-void fraction meter (Capacitance type meter) was applied to high void fraction measurement with various shapes of flow conduits such as round, rectangular and rod-bundle geometries. The principle of the meter is that the electrical capacitance of a gas-liquid two-phase flow changes with the void fraction. High-frequency power supply enables to measure the electrical capacitance of the ion-exchanged water with even though conductivity as low as 1 μS/cm. It was confirmed by the air-water and steam-water boiling two-phase flow experiments that void fraction can be obtained in real time way. Void fraction ranging from 0 to 0.9 at maximum was successfully measured under steam-water boiling two-phase flow conditions of 2 MPa through 18 MPa pressure.

36001208
Numerical simulation of fluid mixing phenomena in boiling water reactor core using advanced interface-tracking method (in Japanese)
Yoshida, Hiroyuki; Nagayoshi, Takuji*; Zhang, W.; Takase, Kazuyuki
Nippon Kikai Gakkai Rombunshu, B 74(742), p.1278-1286(2008) ; (JAEA-J 04510)

36001209
Dynamics and structure formation of atmospheric microwave breakdown (in Japanese)
Oda, Yasuhisa; Komurasaki, Kimiya*; Sakamoto, Keishi
Purazuma, Kaku Yugo Gakkai-Shi 84(6), p.343-347(2008) ; (JAEA-J 04511)

36001210
Project of OWTF (Oarai Waste Reduction Treatment Facility) in JAEA (in Japanese)
Okubo, Toshiyuki
RANDEC Nyusu (77), p.7-8(2008) ; (JAEA-J 04513)

36001211
In vivo cyst formation from the implanted larval integument in the sweet potato hornworm, Agrus convilvuli, as a simple model for studing wound healing (in Japanese)
Fukamoto, Kana
Sanshi, Konchu Biotekku 77(1), p.17-18(2008) ; (JAEA-J 04514)

36001212
Contemporary issues of academic library services from perspective of "emotional labor" (in Japanese)
Ikeda, Kiyoshi; Donkai, Saori*
Toshokankai 60(2), p.134-140(2008) ; (JAEA-J 04515)

36001213
Photoabsorption, photoionization, and neutral dissociation cross-sections of hydrocarbon molecules; Physicochemical aspects of molecular processes in fusion edge plasmas
Hatano, Yoshihiko
Atomic and Plasma-Material Interaction Data for Fusion, Vol.14 , p.77-84(2008) ; (JAEA-J 04516)

A survey is given of recent progress in the measurements of absolute cross-sections for photoabsorption, photoionization, and neutral dissociation of simple and complex molecules in the vacuum ultraviolet region, where a major part of their oscillator strength distributions due to the interactions of photons with molecules exists. Emphasis is placed on the discussion of the neutral dissociation(i.e., the dissociative excitation)of these molecules which has been considered as the most processes to be studied experimentally. From the viewpoints of the molecular processes in fusion edge plasmas, simple hydrocarbon molecules are chosen for the discussion of the measured cross-section values and the spectroscopy and dynamics of the corresponding processes. It has been shown that these optical cross-section data are of great importance to understand the fundamental processes, not only in photon collision induced reactions but also in electron collision induced reactions.

36001214
Hydrogen production from nuclear energy
Hino, Ryutaro; Yan, X.
Hydrogen Fuel; Production, Transport, and Storage , p.127-159(2008) ; (JAEA-J 04517)

36001215
Evaluation of nuclear knowledge management for the Light Water Reactor and Fusion Reactor; A Case study of Japan Atomic Energy Research Institute (JAERI)
Yanagisawa, Kazuaki
Management of Technology Innovation and Value Creation , p.89-101(2008) ; (JAEA-J 04518)

Light Water Reactor (LWR) and Fusion Reactor (FR) are important intellectual assets that have been developed by JAERI and the author incorporated case studies for assessing the potential benefits of these technologies by means of long-term nuclear knowledge management (NKM). (1) For LWR, the benefit from JAERI activity to the taxpayers was estimated to be about 6.3 billion dollars, and the cost-benefit ratio of the JAERI program is 1.5. (2) This study indicates that the use of FR may have an enough cost performance in the future.

36001216
Phase separation and solidification of fluid phosphorus
Katayama, Yoshinori; Inamura, Yasuhiro; Saito, Hiroyuki; Utsumi, Wataru
Materials Research Society Symposium Proceedings, Vol.987 , p.73-78(2007) ; (JAEA-J 04519)

In-situ X-ray diffraction study revealed that there were two distinct structures of fluid phosphorus and a sharp transition occurred between them at about 1 GPa. The two structures, one is molecular fluid and the other is polymeric fluid, have different densities. By an X-ray radiography method, macroscopic separation of two fluid phases was directly observed. These results support a view that it is a first-order phase transition. To study solidification of low-density, high-density fluids and their mixture, an X-ray radiograph has been recorded during a rapid cooling using a cubic-type multi-anvil apparatus installed on a beamline BL14B1 at SPring-8. The obtained solid sample was investigated by an optical microscope and by an electron microscope. The low-density fluid tends to transform to a kind of red phosphorus while high-density fluid usually transforms to black phosphorus. Several shapes of grains were obtained from mixture.

36001217
Multi-wire profile monitor for J-PARC 3GeV RCS
Hiroki, Seiji; Hayashi, Naoki; Kawase, Masato; Noda, Fumiaki; Saha, P. K.; Sako, Hiroyuki; Takahashi, Hiroki; Ueno, Akira; Arakida, Yoshio*; Lee, S.*; Toyama, Takeshi*
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM) , p.1131-1133(2008) ; (JAEA-J 04520)

A set of six multi-wire profile monitors (MWPMs) has been installed in the injection area of the RCS (Rapid-Cycling Synchrotron), and contributed to the initial commissioning for establishing an optimum injection orbit. The Au coated W wires (0.1 mm dia.) for the H- beam are fixed to a ceramic wind frame for two directions (horizontal and vertical with 17.7 deg. tilt, typically 51 wires with 2.9 mm or 9.5 mm distance), and the frame can be scanned for horizontal or vertical direction by using a stepping-motor driven actuator. A combination of the 17.7 deg. tilt wires and the precise scan function provides two step measurements, i.e. a rough profile is obtained only at one shot, and a detailed profile is measured for typically 101 shots (10 mm scan at 0.1 mm interval) thereafter. The beam induced charge signals are amplified, integrated and held by using a signal processing circuit. The signals are sequentially retrieved through multiplexers and digitized for obtaining a beam profile.

36001218
Beam uniformization using multipole magnets at the JAEA AVF cyclotron
Yuri, Yosuke; Ishizaka, Tomohisa; Yuyama, Takahiro; Okumura, Susumu; Ishibori, Ikuo; Miyawaki, Nobumasa; Kurashima, Satoshi; Yoshida, Kenichi; Kashiwagi, Hirotsugu; Agematsu, Takashi; Nara, Takayuki
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM) , p.3077-3079(2008) ; (JAEA-J 04521)

It has been known that uniformization of a beam with a Gaussian profile is possible utilizing odd-order nonlinear forces. Here, we investigate uniformization of the transverse beam profile using nonlinear focusing forces produced by multipole magnets, including even-order forces. The result demonstrates a potential to uniformize an asymmetric beam as well as a Gaussian beam by making a combination of the even and odd-order nonlinear forces. Such a combination technique enables us to perform high-uniformity irradiation at a constant particle fluence rate over the whole area of a large target. A research and development on the beam uniformization system composed of sextupole and octupole magnets is now in progress at the JAEA AVF cyclotron facility. Some results of preliminary experiments are also reported.

36001219
Heating rate of highly space-charge-dominated ion beams in a storage ring
Yuri, Yosuke; Okamoto, Hiromi*
Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM) , p.3080-3082(2008) ; (JAEA-J 04522)

We investigate the heating process of highly space-charge-dominated ion beams in a storage ring, using the molecular dynamics simulation technique. To evaluate the heating rate over the whole temperature range, we start from an ultra-low-emittance state where the beam is Coulomb crystallized, apply perturbation to it, and follow the emittance evolution. When the ring lattice is properly designed, the heating rate is quite low at ultralow temperature because random Coulomb collisions are suppressed. It gradually increases after the collapse of the ordered state by perturbation, and comes to a peak when the beam reaches a liquid phase. The dependence of the heating behavior on the beam line density and betatron tune is explored systematically. The effect of lattice imperfection on the stability of crystalline beams is also confirmed.

36001220
Reduction of radioactive secondary waste with steam reforming in treatment of waste TBP/dodecane
Sone, Tomoyuki; Sasaki, Toshiki; Yamaguchi, Hiromi
Proceedings of 11th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM '07) (CD-ROM) , 5p.(2007) ; (JAEA-J 04523)

We have stored waste TBP/dodecane generated from R&D activities on recycle of nuclear fuel. Those wastes can be incinerated, however a large quantity of contaminated phosphorous compounds generate. The objective of this study is to reduce the generation of radioactive secondary waste by the treatment of those wastes using steam reforming system. We conducted process demonstration tests using waste TBP/dodecane with 0.07g/L of uranium. We studied the temperature dependence of the gasification ratio of inorganic phosphorus compounds and removal of uranium by the filter. As the results, more than 95% of phosphorus compounds were gasified at temperature of 600°C or more, and more than 98% of uranium compounds were separated from the vaporized waste. The separated phosphorus compounds can be disposed of as the liquid wastes of which concentration of uranium is under the regulatory level. These results show the steam reforming system is effective in the reduction of radioactive secondary waste in the treatment of TBP/dodecane.

36001221
Developments at JAEA AVF cyclotron facility for heavy-ion microbeam
Kurashima, Satoshi; Okumura, Susumu; Miyawaki, Nobumasa; Ishibori, Ikuo; Yoshida, Kenichi; Sato, Takahiro; Kashiwagi, Hirotsugu; Yuri, Yosuke; Agematsu, Takashi; Nara, Takayuki; Kamiya, Tomihiro; Yokota, Wataru; Oikawa, Masakazu*; Fukuda, Mitsuhiro*
Proceedings of 18th International Conference on Cyclotrons and Their Applications (CYCLOTRONS 2007) , p.131-133(2007) ; (JAEA-J 04524)

We have been improving the beam quality of the JAEA (Japan Atomic Energy Agency) AVF cyclotron to form a several-hundred-MeV heavy-ion microbeam by a magnetic focusing lens. An energy spread ΔE/E of the order of 10^-3, obtained by ordinary acceleration using a fundamental dee voltage, makes it difficult to focus an ion beam to a spot size of 1 μm in diameter with focusing lens because of the chromatic aberration. A flat-top acceleration system using the fifth-harmonic frequency of the acceleration frequency was installed in the cyclotron in order to reduce ΔE/E to the order of 10^-4. In addition, developments of a new center region, an energy spread measurement system using an analyzing magnet and a high performance beam buncher are in progress. The energy spread of the 260 MeV ²⁰Ne⁷⁺ beam has been reduced to 0.05% by the flat-top acceleration, and the microbeam with a spot size of approximately 1 μm has been successfully formed.

36001222
A Probabilistic evaluation model for welding residual stress distribution at piping joint in probabilistic fracture mechanics analysis
Ito, Hiroto; Katsuyama, Jinya; Onizawa, Kunio
Proceedings of 2008 ASME Pressure Vessels and Piping Conference (PVP 2008) (CD-ROM) , 6p.(2008) ; (JAEA-J 04525)

In JAEA, we have been developing probabilistic fracture mechanics (PFM) analysis methods for aged piping based on latest aging knowledge and an analytical code, PASCAL-SP. PASCAL-SP evaluates the failure probability of piping at aged welded joints under SCC and In-Service Inspection by a Monte Carlo method. We proposes a probabilistic model which can be applied to the failure probability analysis based on PFM for welded joint of piping considering the uncertainty of welding residual stress. And the probabilistic evaluation model is introduced to PASCAL-SP. A parametric PFM analysis concerning uncertainties of residual stress distribution using PASCAL-SP was performed. The PFM analysis showed that the uncertainties of residual stress distribution about heat input and welding speed largely influenced break probability. The break probability increased with increasing the uncertainties.

36001223
Effect of surface-machining and butt-welding on residual stress and hardness of type 316L stainless steel pipes
Asano, Wataru*; Katsuyama, Jinya; Onizawa, Kunio; Mochizuki, Masahito*; Toyoda, Masao*
Proceedings of 2008 ASME Pressure Vessels and Piping Conference (PVP 2008) (CD-ROM) , 8p.(2008) ; (JAEA-J 04526)

Stress corrosion cracking near welding zone of core internals and/or recirculation pipes of Type 316L stainless steel are initiated and grown at inner surface due to tensile residual stress and hardening. Surface-machining is conducted before and after piping butt-welding to match the ID of pipes and to provide a smooth surface finish, respectively. In present work, simulation evaluated residual stress by surface-machining before welding by using full scale FEM analysis was compared with experimental measurements. Piping-butt welding simulation was conducted after the surface-machining to evaluate redistribution behavior of residual stress by welding. Estimation of Vickers hardness distribution by surface-machining was carried out based on strained region map observed by FE-SEM equipped with EBSD and compared with experimental measurements. The effect of surface-machining before/after welding on distribution of residual stress and hardening are presented.

36001224
Effect of welding conditions on residual stress and SCC behavior at butt-welding joints of recirculation pipes
Katsuyama, Jinya; Tobita, Toru; Ito, Hiroto; Onizawa, Kunio
Proceedings of 2008 ASME Pressure Vessels and Piping Conference (PVP 2008) (CD-ROM) , 9p.(2008) ; (JAEA-J 04527)

Stress corrosion cracking (SCC) in recirculation pipes has been observed near butt-welding joints due to high tensile residual stress by welding. In present work, scatters of welding conditions such as heat input and welding speed were measured experimentally by producing a series of butt-welding pipe specimens. Distribution and its scattering of residual stress were also measured by non-destructive and destructive methods. The effects of welding conditions on residual stress have been evaluated by parametric FEM analyses considering the variation of some parameters based on the welding experiments. The effects of welding conditions on crack growth behavior have been also evaluated by SCC growth simulations using calculated residual stress distributions and a procedure in the fitness-for-service code. Welding conditions such as heat input and welding speed have a strong influence on crack growth rate since residual stress is also affected by scatter of these welding conditions.

36001225
Anion exchange fibres derived from chloromethylstyrene grafted POLYOLEIN FIBRES for rapid column-mode removal of nitrate in water
Go, Yasuhiro*; Yoshida, Hiromi*; Jo, Akinori*; Tamada, Masao; Katakai, Akio
Proceedings of 2008 Conference on Ion Exchange Technology (IEX 2008) , p.353-361(2008) ; (JAEA-J 04528)

Although granular anion exchange resins are useful for column-mode removal of nitrate in water, sizes of granular resins used in industrial scale columns are ca. 0.5 mm to reduce pressure loss in column operations. Since large granular resins bring down adsorption kinetics, it is difficult to supply water polluted with nitrate to granular resin packed columns at extremely high flow rates more than 1000 h^-1 in space velocity (SV). In this work, we have prepared an anion exchange fiber named FBDA, which rapidly takes up nitrate in column-mode even at the flow rate of feed of 3000 h^-1 in SV. FBDA was prepared by electron beam irradiation induced liquid phase graft polymerization of chloromethylstyrene (CMS) onto polyethylene-coated polypropylene fiber (PPPE; 1.5 denier) and the subsequent quaternization of the CMS-grafted fiber with n-butyldimethylamine (BDA). The resulting BDA-fixed fiber (FBDA) has anion exchange capacity of 2.2 meq/g. To the column (i.d. 1.3 cm) containing 2.0 mL wet FBDA, 1 mM nitrate feeding solutions in the absence and presence of a competing anion was fed to the column at given flow rates. In the absence of a competing anion, shapes of breakthrough profiles of nitrate are independent of the flow rates from 1000 to 3000 h^-1 in SV, giving the constant breakthrough capacity for nitrate as high as 1.1 mmol/g. Effect of chloride and sulfate was tested at the flow rate of 1000 h^-1. In the presence of 1 mM and 5 mM chloride, breakthrough capacities for nitrate were reduced to 0.83 and 0.48 mmol/g, respectively. However, equimolar sulfate reduced the breakthrough capacity down to 0.43 mmol/g. Thus, the presented FBDA is useful for rapid purification of water contaminated with low concentration levels of nitrate, so long as concentrations of chloride and sulfate are nearly equal orders as those in most river waters. Almost the same results were also obtained in case of the triethylamine-fixed fiber named FTEA.

36001226
Development of advanced loop-type fast reactor in Japan, 5; Adoption of self-actuated shutdown system to JSFR
Nakanishi, Shigeyuki; Kubo, Shigenobu*; Takamatsu, Misao; Ikarimoto, Iwao*; Kato, Jungo*; Shimakawa, Yoshio*; Harada, Kiyoshi*
Proceedings of 2008 International Congress on Advances in Nuclear Power Plants (ICAPP '08) (CD-ROM) , p.519-525(2008) ; (JAEA-J 04529)

A self-actuated shutdown system (SASS) is a passive safety feature which inserts control rods by the gravity force, where the detachment of the rods would be achieved by the coolant temperature rise under anticipated transient without scram (ATWS) conditions. Various out-of-pile tests have already carried out to investigate the basic characteristics of SASS, and a demonstration test of holding stability under the reactor operation condition has been performed, where a function test of the driving system to re-connect and of pulling out the control rod have been done in the experimental reactor JOYO. The element irradiation tests have been also conducted to confirm that no impact will be foreseen by the irradiation. The effectiveness of SASS for a reference core design of JSFR has been evaluated through all types of ATWS. As a result, it is ensured that JSFR will have a reliable passive shutdown system.

36001227
Activities of Caisson Assembly for Tritium Safety study (CATS) at TPL/JAEA
Kobayashi, Kazuhiro; Hayashi, Takumi; Iwai, Yasunori; Isobe, Kanetsugu; Nakamura, Hirofumi; Kawamura, Yoshinori; Shu, Wataru; Suzuki, Takumi; Yamada, Masayuki; Yamanishi, Toshihiko
Proceedings of 2nd Japan-China Workshop on Blanket and Tritium Technology , p.74-78(2008) ; (JAEA-J 04530)

In order to accumulate the tritium behavior in the future fusion reactor included ITER, intentional tritium release experiments have been carried out using Caisson Assembly for Tritium Safety study (CATS) at Tritium Process Laboratory (TPL) in Japan Atomic Energy Agency (JAEA). Main objectives of CATS are (1) to demonstrate the initial tritium behavior in the room and to develop 3D simulation code of tritium behavior in the room. (2) to demonstrate the performance of integrated system for tritium confinement after intentional tritium release accident, (3) to accumulate the data for the detritiation behavior and the interaction between various materials and tritium (tritiated water) in the confinement. The study using CATS has been continued for about 10 yeas in TPL/JAEA.

36001228
Extraction and flow sheet studies for U and Pu separation by N,N-di(2-ethyl)hexylbutanamide
Ban, Yasutoshi; Hagiya, Hiromichi; Sato, Makoto; Asakura, Toshihide; Morita, Yasuji
Proceedings of 3rd International ATALANTE Conference (ATALANTE 2008) (CD-ROM) , 4p.(2008) ; (JAEA-J 04531)

Since N,N-dialkylamide (monoamide) compounds extract tetravalent and hexavalent actinides, they have been proposed as alternative extractants to TBP. In the present work, numerical calculations for estimating separation performance of N,N-di(2-ethyl)hexyl-butanamide (D2EHBA) for U(VI) and Pu(IV) were carried out. A flow sheet was obtained which separate more than 99.9% of Pu(IV) from U(VI) by adjusting nitric acid concentration. Extraction properties of D2EHBA for macro concentrations of U (0.63-1.22 mol/dm³(M)) and Pu (6.3 mM) were studied in a batch manner. D2EHBA diluted to 1.5 M by n-dodecane extracted up to 0.8 M of U(VI) without forming precipitation and third phase. Distribution ratios of Pu(IV) were relatively high compared with the ones obtained at tracer concentrations of Pu(IV).

36001229
Extraction separation of Am(III) and Eu(III) with thermosensitive gel introducing TPEN derivatives
Takeshita, Kenji*; Nakano, Yoshio*; Matsumura, Tatsuro; Mori, Atsunori*
Proceedings of 3rd International ATALANTE Conference (ATALANTE 2008) (CD-ROM) , 8p.(2008) ; (JAEA-J 04532)

A thermal-swing chromatographic process using a thermosensitive gel copolymerized with NIPA (N-isopropylacrylamide) and TPPEN (N,N,N',N'-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine) was studied for the separation of Am(III) from Eu(III). Firstly, the radiolysis of the TPPEN-NIPA gel was tested by the γ-ray irradiation and the α nuclide adsorption. The extraction separation of Am(III) was not influenced in the radioactive environment of the proposed process. Next, the TPPEN-NIPA gel was immobilized in porous silica particles and the applicability of the gel-immobilized silica to the proposed process was tested. Am(III) was extracted selectively in the gel-immobilized silica at 5°C and the separation factor of Am(III) over Eu(III) was evaluated to be 3.7. The distribution ratio of Am(III) was reduced to less than 1/20 by increasing temperature from 5°C to 40°C. These results indicate that the TPPEN-NIPA gel is applicable to the thermal-swing chromatographic process for the MA recovery.

36001230
Recent Japanese research activities on probabilistic fracture mechanics for pressure vessel and piping of nuclear power plant
Kanto, Yasuhiro*; Onizawa, Kunio; Machida, Hideo*; Isobe, Yoshihiro*; Yoshimura, Shinobu*
Proceedings of 7th International Conference on the Integrity of Nuclear Components , p.219-228(2008) ; (JAEA-J 04533)

This paper describes a review of recent Japanese activities on probabilistic fracture mechanics (PFM) analyses. JAEA had sponsored research committees on PFM organized by the Japan Society of Mechanical Engineers and the Japan Welding Engineering Society (JWES) for more than a decade. This work still continues with the same members in JWES. The purpose of the continuous activity is to provide probabilistic approaches in several fields of integrity of reactor components. This paper summarizes some of the latest results of this activity. First topic is evaluation of the JSME rules on Fittness-For-Service from the view of PFM, including reactor pressure vessel with a crack of the allowable size, and effect of sizing accuracy in inspection. The next one is development of new PFM techniques including piping reliability assessment on domestic SCC data and maintenance optimization based on risk and economic models. The last is the international round robin program just starting from 2008.

36001231
Development of probabilistic fracture mechanics analysis codes for reactor pressure vessels and piping considering welding residual stress
Onizawa, Kunio; Nishikawa, Hiroyuki; Ito, Hiroto
Proceedings of 7th International Conference on the Integrity of Nuclear Components , p.229-239(2008) ; (JAEA-J 04534)

Probabilistic fracture mechanics (PFM) analysis codes for reactor pressure vessel (RPV) and piping, called as PASCAL series are being developed at JAEA, For an RPV, PASCAL2 code has been developed which can evaluate the conditional probabilities of crack initiation and fracture under transient conditions such as pressurized thermal shock. Recent improvements on the PASCAL2 are related to weld overlay cladding. It is shown that the welding residual stress by cladding affects the fracture probability of RPV to some extent. For piping, considering stress corrosion cracking, PASCAL-SP has been developed. The PASCAL-SP evaluates the probabilities of piping failures such as leakage and break of safety-related piping according to Japanese regulation and rules. Residual stress distribution was determined by parametric FEM analyses after verifying with welding experiments. Effects of welding residual stress distribution as well as inspection accuracy have been studied.

36001232
Accelerator-based facility design in association with nuclear data
Takada, Hiroshi
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.1 , p.23-28(2008) ; (JAEA-J 04535)

In the design study of a large accelerator facility using high energy and high intensity beam accelerator as examples of J-PARC and SNS, it is required to seek the best neutronic performance and assure engineering feasibilities such as heat removal from the target and its surroundings, capability on installation and assembling, material selection to have enough life-time under radiation environment for reasonable operation duration. It is also important to design sophisticated maintenance scheme to treat highly activated components, and optimal radiation shield around accelerator components and secondary beam lines. High energy nuclear data file and accumulation of new experimental data are indispensable to improve or to know the prediction accuracy of neutronics design by a computer simulation using a model independent of the nuclear data. In this paper, roles of nuclear data in design of accelerator facilities is presented.

36001233
Problem on unresolved resonance data in recent nuclear data libraries
Konno, Chikara; Nakagawa, Tsuneo; Ochiai, Kentaro; Sato, Satoshi; Yamauchi, Michinori
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.1 , p.713-716(2008) ; (JAEA-J 04536)

A leakage neutron spectrum from a niobium sphere of 0.5 m in radius with a 20 MeV neutron in the center, which was calculated with ANISN, MCNP and JENDL-3.3, had a large strange bump around 100 keV, which originated from the unresolved resonance data. We checked cross section data of (n,γ) reaction and elastic scattering in ⁹³Nb with and without self-shielding correction by using a multigroup library of JENDL-3.3. The self-shielding correction of the unresolved resonances seems to be too large even around the upper energy of the unresolved resonance region. It is considered that the average reduced neutron widths or the upper energy of the unresolved resonance region in ⁹³Nb have any problems. It is found out that many nuclei with unresolved resonance data in JENDL-3.3 and ENDF/B-VI have the similar problem. The unresolved resonance data in JENDL-3.3 and ENDF/B-VI should be revised by considering self-shielding correction in the next version.

36001234
Recent advances in the JENDL project
Shibata, Keiichi; Nakagawa, Tsuneo; Fukahori, Tokio; Iwamoto, Osamu; Ichihara, Akira; Iwamoto, Nobuyuki; Kunieda, Satoshi; Otsuka, Naohiko; Katakura, Junichi; Watanabe, Yukinobu*; Kosako, Kazuaki*
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.2 , p.727-732(2008) ; (JAEA-J 04537)

General- and special-purpose JENDL data files are being produced in cooperation with the Japanese Nuclear Data Committee. We have developed nuclear model codes to improve the quality of MA and FP data. In the FP region, we obtained global coupled-channel optical model parameters, which can be applied to neutron- and proton-induced reaction data up to 200 MeV. These parameters are used for statistical model calculation. Resolved resonance parameters of MA and FP nuclei were updated to improve the low-energy behavior of the cross sections by using recent measurements. As a follow-up of JENDL-3.3, which was released in 2002, covarainces of several nuclei were estimated for a study on ADS. Concerning special-purpose files, the compilation of the 2007 versions of JENDL High Energy File and Photonulcear Data Files is in the final stage.

36001235
Status and future work of the NEA working party on international nuclear data evaluation cooperation
Koning, A.*; Katakura, Junichi; Oblozinsk'y, P.*; Nichols, A. L.*; Nordborg, C.*
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.2 , p.741-746(2008) ; (JAEA-J 04538)

The Working party on international nuclear data Evaluation Cooperation (WPEC) is a collaborative effort between the major OECD nuclear data project: ENDF/B (USA), JENDL (Japan) and JEFF (Europe), and the IAEA-supported non-OECD project CENDL (China) and BROND (Russia). Nuclear data challenges and problems that are common to all projects are considered in various WPEC subgroups that are normally pf limited time span. The achievements of these subgroups are reviewed in this paper. Among the recent accomplishments are improved criticality predictions through revised U evaluations, the completion of new cross-section standards, and the creation of a new Fission Product library. Problems that are currently being addressed are the processing and inclusion of covariance data in the libraries, improvements in decay data to assist in decay heat calculations, assembly of a well-structured High Priority Request List, validation of the new fission product cross-section library, and the assessment of nuclear data needs for GEN-IV.

36001236
Benchmark of evaluated nuclear data libraries using post-irradiation experimental data on fuel composition changes of the fast reactor JOYO
Yokoyama, Kenji; Jin, Tomoyuki*
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.2 , p.807-810(2008) ; (JAEA-J 04539)

Post irradiation experiment (PIE) data on depleted fuel composition of the experimental fast reactor "JOYO" MK-II has been accumulated since 1986 in JNC (the former of JAEA). In the present study, all the available PIE data of JOYO MK-II driver fuel were analyzed and integral data concerning ²³⁵U depletion and ²³⁶U generation were prepared. Both the integral data are sensitive to ²³⁵U capture cross section and applicable to nuclear data benchmarks. The recent evaluated nuclear data libraries, JENDL-3.2, -3.3, JEFF-3.1 and ENDF/B-VII, have a tendency to overestimate the generation of ²³⁶U. A cross section adjustment demonstrated that re-evaluation of ²³⁵U capture cross section improved the overestimation.

36001237
Development needs of nuclear data for fusion technology
Fischer, U.*; Batistoni, P.*; Forrest, R. A.*; Konno, Chikara; Perel, R. L.*; Seidel, K.*; Simakov, S. P.*
Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2007), Vol.2 , p.973-978(2008) ; (JAEA-J 04540)

An overview is presented of the nuclear data required for nuclear design analyses of fusion technology focusing on ITER, the International Thermonuclear Experimental Reactor, and IFMIF, the International Fusion Materials Irradiation Facility. The status of the available data evaluations and libraries is reviewed with regard to the required materials/nuclides and data types and, in particular, with regard to their quality as compared to differential and integral experimental data. Future development needs are identified on this basis addressing nuclear data evaluations for neutron and photon transport simulations, cross-section data for activation and transmutation calculations, and co-variance data for uncertainty analyses.

36001238
Thermal pretreatment for TRU waste sorting
Sasaki, Toshiki; Aoyama, Yoshio; Miyamoto, Yasuaki; Yamaguchi, Hiromi
Proceedings of International Waste Management Symposium 2008 (WM '08) (CD-ROM) , 8p.(2008) ; (JAEA-J 04541)

Japan Atomic Energy Agency conducted a study on thermal treatment of TRU waste to develop a removal technology for materials that are forbidden to dispose of. The thermal pretreatment in which hot nitrogen and/or air is introduced to the waste is a process of removing combustibles, liquids, and low melting point metals from PVC wrapped TRU waste. In this study, thermal pretreatment of simulated waste was conducted using a desktop thermal treatment vessel and a laboratory scale thermal pretreatment system. Combustibles such as papers, PVC, oil, etc. were removed and low melting point metals such as zinc, lead, and aluminum were separated from the simulated waste by the thermal pretreatment.

36001239
Knowledge management; The Cornerstone of a 21st century safety case
Umeki, Hiroyuki; Osawa, Hideaki; Naito, Morimasa; Nakano, Katsushi; Makino, Hitoshi; McKinley, I. G.*
Proceedings of Safety Cases for Deep Geological Disposal of Radioactive Waste; Where do we stand ? , p.211-219(2008) ; (JAEA-J 04542)

36001240
Influence of normalising temperature on MX precipitation behaviour in high-chromium steel
Obara, Satoshi; Onizawa, Takashi; Wakai, Takashi; Asayama, Tai
Proceedings of Workshop on Structural Materials for Innovative Nuclear Systems (SMINS) , p.115-126(2008) ; (JAEA-J 04543)

This study investigates the influence of normalising temperature on metal carbonitride (MX) precipitation behavior and mechanical property of high chromium (Cr) ferritic steel for sodium cooled fast reactor (SFR) structures. Generally, mechanical strength in high Cr steel is increased addition of vanadium (V) and niobium (Nb), because V and Nb play a role of precipitation strengthening elements as metal carbonitride (MX) particles. However, precipitation behavior depends not only on the amount of V and Nb but also on the heat treatment conditions. In this presentation, in order to investigate the optimum heat treatment conditions for FBR structural materials, several kinds of high Cr steels with different heat treatments were produced and a series of mechanical tests and metallurgical examinations were conducted.

36001241
Development of soften poly(lactic acid) material with transprancy at room temperature (in Japanese)
Nagasawa, Naotsugu; Kanazawa, Shinichi*; Tamada, Masao
Baiopurasuchikku No Kokinoka, Saishigenka Gijutsu , p.162-169(2008) ; (JAEA-J 04544)

36001242
Assessment of preventing maintenance on Japanese Research Reactor JRR-3 (in Japanese)
Kobayashi, Tetsuya; Ichimura, Toshiyuki; Sato, Masayuki
Nippon Hozen Gakkai Dai-5-Kai Gakujutsu Koenkai Yoshishu , p.340-343(2008) ; (JAEA-J 04546)

The maintenance evaluation for research reactors has been obligated in Japan from 2004 as for power reactors. JAEA (Japan Atomic Energy Agency) has started to evaluate the maintenance for own research reactors on 2004. In this paper, we report the present status of the maintenance for JRR-3 (Japanese Research Reactor No.3), as well as the linear evaluation methods used. It is found that a series of preventing maintenance task on equipment and building of the reactor is properly performed.

36001243
Activity of safety review for the facilities using nuclear material (in Japanese)
Fujishima, Tadatsune; Sakamoto, Naoki; Mizukoshi, Yasutaka; Amagai, Tomio; Omori, Tsuyoshi
Nippon Hozen Gakkai Dai-5-Kai Gakujutsu Koenkai Yoshishu , p.388-392(2008) ; (JAEA-J 04547)

36001244
Research for determination of elemental ratio between Uranium and Plutonium by Non-destructive method (in Japanese)
Takamine, Jun; Haruyama, Mitsuo; Takase, Misao
Nippon Hozen Gakkai Dai-5-Kai Gakujutsu Koenkai Yoshishu , p.481-484(2008) ; (JAEA-J 04548)

We have not yet known the nondestructive detection method to determine each quantity of the object which Uranium and Plutonium is mixed in, such a waste generated from nuclear fuel cycle facility, and so radioactive intensity of Pu-239 is 10,000 times as much as U-235. Therefore, on radioactive assessment, it is important to precisely quantify each mass. Then we paid attention to the component of delayed and prompt neutron obtained by 14 MeV neutron direct interrogation method and so developed the new method to determine mass ratio between Uranium and Plutonium from those correlations.

36001245
High power test of 972 MHz waveguide systems for J-PARC Linac (in Japanese)
Hori, Toshihiko; Yamazaki, Masayoshi; Yamaguchi, Seiya*; Hasegawa, Kazuo; Linac RF Group
NIFS-MEMO-55 , p.289-292(2008) ; (JAEA-J 04550)

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