Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Hada, Kazuhiko; Nishi, Hiroshi; Hirose, Takanori; Mori, Kensuke; Aoki, Shoji*; Wada, Masahiko*; Yamamichi, Tetsuo*
no journal, ,
Chromium-zirconium copper as precipitation hardened copper alloy is examined as one of the structural materials used for the ITER in vacuum vessel components. The process that consists of a thermomechanical treatments series of the solution treatment with rapid cooling to obtain the supersaturated solid solution and the aging treatment etc., is adopted in order to obtain the demanded high strength in manufacturing of this alloy material. However, as this alloy is precipitation hardened copper alloy, it is concerned that the great change in the strength characteristic is caused by the thermomechanical treatments conditions, especially the difference of the quenching cooling rate after the solution treatment in manufacturing. In this research, the influence of the quenching cooling rate condition after the solution treatment and the other conditions on this copper alloy was investigated by measuring the tensile test properties of the specimens that are prepared by treatments with some quenching cooling rate conditions after the solution treatment and aging treatment. One of the typical results from this study is that, for the quenching cooling rate after the solution treatment, it was understood that the cooling rate change from 1 to 10
C/s causes the great growth in the tensile strength. Therefore, when this alloy component is manufactured by heat history process like HIP process and needed to be treated solution treatment to be use for the structural component, it is important to guarantee the strength of the product by checking the quenching cooling rate after the solution treatment.
/U
in molten NaCl-2CsClNagai, Takayuki; Uehara, Akihiro*; Shirai, Osamu*; Yamana, Hajimu*
no journal, ,
no abstracts in English
Adachi, Motoyasu; Tamada, Taro; Sato, Katsuya*; Narumi, Issei; Kuroki, Ryota
no journal, ,
The resistance of Deinococcus radiodurans to 
-ray is 1000 times higher than that of human cells. PprA is the novel protein which promotes repairing DNA, and play a key role in the ability to resist to the radiation. The characterization of PprA have showed: (1) that the expression of PprA is controlled under another novel protein of PprI (2) that PprA promotes ligase reaction: (3) that pprA exhibits the ability to bind on DNA. In this study, our objective is the crystal structure analysis of PprA to reveal its structure-function relationships and for application as genetic and clinical tools. Here, we constructed the E. coli expression and purification system of PprA. Using the purified PprA, some small crystals in size were obtained after screening of conditions for crystalization. Beased on the analyses of DNA-PprA interaction, we showed that 280 molecules of PprA at least can bind on a DNA molecule of pUC19 plasmid (2686bp). In addition, we indicated that several DNA-PprA complexes may form higher complex, when DNA includes terminal end or nick (the cleaved part on a DNA strand). These results are important knowledge in molecular assembly and function of PprA.
Komuro, Yo; Hirade, Tetsuya; Suzuki, Ryoichi*; Odaira, Toshiyuki*; Muramatsu, Makoto*
no journal, ,
The annihilation rays from the para-pojitoronium (p-Ps) state gives narrower Doppler broadening. The broader Doppler broadening was observed at very young age region that is mainly from the annihilation process of p-Ps. It was explained by the delayed Ps slowing down and the delayed Ps formation. We have successfully obtained the experimental evidence of the delayed Ps formation.
Miyauchi, Toru; Koarashi, Jun; Mikami, Satoshi; Kozawa, Tomoyasu*; Yokota, Tomokazu*; Isaka, Keisuke*; Akiyama, Kiyomitsu
no journal, ,
no abstracts in English
Taguchi, Mitsumasa; Baldacchino, G.*; Pin, S.*; Vigneron, G.*; Hichel, B.*; Kojima, Takuji
no journal, ,
no abstracts in English
Mikami, Satoshi; Miyauchi, Toru; Koarashi, Jun; Kozawa, Tomoyasu*; Yokota, Tomokazu*; Isaka, Keisuke*; Akiyama, Kiyomitsu
no journal, ,
no abstracts in English
Koike, Masato; Sano, Kazuo*; Sasai, Hiroyuki*
no journal, ,
The flat field spectrographs are coming into the limelight once again taking the advantages of the rapid progress of the solid state imaging devices, and the needs of the ultra-high speed simultaneous measurements reaching to femto- or atto- seconds. A typical soft X-ray spectrograph employs a mechanically ruled varied-line-spacing spherical grating. We have also developed a holographic grating for this spectrograph,and spectrographs of this type are used in a variety of research areas. However it utilizes a pseudo-flat image plane near the point of inflection of the focal curve called lemniscates. Therefore the obtainable resolving power is limited and it is difficult to reach to several thousands. Also it is still a challenging subject to extend to the multi-keV region due to the degradation of the diffraction efficiency. We describe the recent progress of the soft X-ray flat field holographic grating spectrographs, a design study of a high resolution spectrograph using a varied-line-spacing plane grating, and the possible options to extend them to the multi-keV region.
Fukaya, Yuki; Kawasuso, Atsuo; Ichimiya, Ayahiko
no journal, ,
no abstracts in English
Asano, Masaharu; Chen, J.; Yamaki, Tetsuya; Yoshida, Masaru
no journal, ,
To prepare proton-conducting membranes with an excellent mechanical characteristic, a mixture of styrene and divinylbenzene was grafted into various base materials such as CF2-derivatives (PTFE, PFA and FEP) and CF2/CH2-derivatives (ETFE and PVDF). It was found that the introduction of graft-chains into CF2/CH2-derivatives was easier compared with that of CF2-derivatives. These derivatives that introduced the graft-chains were then sulfoanted, in order to determine the tensile strength, as a resulting of higher tensile strength for sulfonated CF2/CH2-derivatives
Seki, Takayoshi; Hanada, Masaya; Tobari, Hiroyuki; Inoue, Takashi; Takado, Naoyuki*; Mizuno, Takatoshi*; Hatayama, Akiyoshi*; Kashiwagi, Mieko; Taniguchi, Masaki; Watanabe, Kazuhiro; et al.
no journal, ,
no abstracts in English
Tateiwa, Naoyuki; Haga, Yoshinori; Matsuda, Tatsuma; Ueda, Taiki*; Thamizhavel, A.*; Nakashima, Miho*; Takeuchi, Tetsuya*; Settai, Rikio*; Onuki, Yoshichika; Knebel, G.*; et al.
no journal, ,
We have developed the system for the heat capacity measurement by the thermocouple in order to study the high pressure physical properties of the rare earth and actinide compounds. In this talk, we would like to show our system and discuss our recent results on the heavy fermion superconductors CePt
Si and UIr. It is noted that the superconductivity of UIr was found by our group. There is no inversion center in crystal structures of both compounds. The superconductivity of both compounds might be the novel type. In the case of CePtSi, the antiferromagnetic phase is strongly suppressed by the applied pressure and disappears above 0.6 GPa, while the superconducting phase exists in the wide pressure region up to 1.5 GPa. It is found that the overall feature of the pressure phase diagram is different from those of other heavy fermion superconductors. In the case of UIr, it is suggested by the resistivity measurement under pressures that there exists multiple ferromagnetic phases in the high pressure region. We investigated the pressure phase diagram of UIr from the thermodynamic point of view. We discuss the relation between the superconductivity and magnetism in UIr.
Minami, Takahiro; Matsubara, Hitoshi; Yamagishi, Nobuhiro; Hasegawa, Yukihiro; Aoyagi, Tetsuo; Nakajima, Norihiro; Tani, Masayuki
no journal, ,
no abstracts in English
Kumada, Hiroaki; Yamamoto, Kazuyoshi
no journal, ,
no abstracts in English
Kokubu, Yoko; Yasuda, Kenichiro; Magara, Masaaki; Miyamoto, Yutaka; Sakurai, Satoshi; Usuda, Shigekazu; Yoshikawa, Shusaku*; Yamazaki, Hideo*
no journal, ,
no abstracts in English
fuelSuzudo, Tomoaki; Itakura, Mitsuhiro; Kaburaki, Hideo
no journal, ,
We have developed a new, simple model of three-dimensional dislocation structures, using phase-field-type strain energy functional calculated from atomic displacement field, taking the periodicity of the crystal structure into account. Using this model, we simulate the relaxation process of condensed dislocation loops created by aggregation of irradiation- induced interstitial atoms to investigate the possibility that these loops become dislocation cell walls and induce the polygonization of high burn-up UO fuel. In addition, we have developed a model of fission-gas-atom clustering and the bubble formation. The model uses a combination of Monte-Carlo simulation and three -dimensional cellular automaton; cellular automata are suitable for the numerical experiments for complex behaviors such as a clustering of atoms. The result has shown that there is a critical concentration of gas atoms to form a stable bubble. The bubble size distributions, generated by the cellular automaton results, are compared with the experimental data and the theoretical results from the master equation approach.
Pu distribution in the lungHirota, Masahiro; Kurihara, Osamu; Takada, Chie; Takasaki, Koji; Momose, Takumaro; Deji, Shizuhiko*; Ito, Shigeki*; Saze, Takuya*; Nishizawa, Kunihide*
no journal, ,
no abstracts in English
Nagame, Yuichiro
no journal, ,
Chemical studies of the transactinide element, rutherfordium (Rf), at JAEA (Japan Atomic Energy Agency) are reviewed. The transactinide nuclide 
Rf has been produced in the nuclear reaction 
Cm(
O, 5n) with the production rate of 2 atoms/min. Ion-exchange experiments on Rf together with the lighter homologues, group-4 elements Zr and Hf, in acidic solutions have been conducted with a rapid ion-exchange separation apparatus. From the systematic study of the ion-exchange behavior of Rf, it has been found that the properties of Rf in HCl and HNO
solutions are quite similar to those of Zr and Hf, definitely confirming that Rf is a member of the group-4 elements. However, we have observed an unexpected chemical behavior of Rf in HF solutions; the fluoro complex formation of Rf is significantly different from those of the homologues. Characteristics of the Rf complexes are discussed by comparing with those of Zr and Hf.
SR Stufies on f-electron compounds