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Aoyagi, Mitsuhiro; Makino, Toru*; Oki, Hiroshi*; Uchibori, Akihiro; Okano, Yasushi
Proceedings of 30th International Conference on Nuclear Engineering (ICONE30) (Internet), 7 Pages, 2023/05
Shamsuzzaman, M.*; Horie, Tatsuro*; Fuke, Fusata*; Kamiyama, Motoki*; Morioka, Toru*; Matsumoto, Tatsuya*; Morita, Koji*; Tagami, Hirotaka; Suzuki, Toru*; Tobita, Yoshiharu
Annals of Nuclear Energy, 111, p.474 - 486, 2018/01
Times Cited Count：17 Percentile：85.18(Nuclear Science & Technology)Okamoto, Yoshihiro; Osugi, Takeshi; Akabori, Mitsuo; Kobayashi, Toru; Shiwaku, Hideaki
Journal of Molecular Liquids, 232, p.285 - 289, 2017/04
Times Cited Count：3 Percentile：12.21(Chemistry, Physical)High energy XAFS measurement using cerium K-edge was performed to study the chemical state of cerium in high-temperature molten slag (SiO
-CaO-FeO
-CeO). It was found from the change in the nearest Ce-O distance obtained from EXAFS analysis and the energetic shift of the white line peak observed in XANES analysis that oxidation state of cerium was tetravalent in the molten state and trivalent in solid state. The Debye-Waller factor of the nearest Ce-O pair in solid slag was very large even at room temperature, and the change in its value upon heating and melting was very small. This result suggests that cerium is highly disordered and stable in solid slag.
Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.
JAEA-Conf 2016-004, p.41 - 46, 2016/09
Neutron- and proton-induced cross-section data are required in a wide energy range beyond 20 MeV, for the design of accelerator applications. New evaluations are performed with recent knowledge in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p+
Li and p+
Be which have been highly requested from a medical field. The present high-energy nuclear data library, JENDL-4.0/HE, includes evaluated cross-sections for incident neutrons and protons up to 200 MeV (for about 130 nuclei). We overview substantial features of the library, i.e., (1) systematic evaluation with CCONE code, (2) challenges for evaluations of light nuclei and (3) inheritance of JENDL-4.0 and JENDL/HE-2007. In this talk, we also focus on the results of benchmark calculation for neutronics to show performance of the present library.
Tomita, Takuro*; Nishikino, Masaharu; Hasegawa, Noboru; Minami, Yasuo*; Takei, Ryota*; Baba, Motoyoshi*; Eyama, Tsuyoshi*; Takayoshi, Shodai*; Kaihori, Takeshi*; Morita, Toshimasa; et al.
Journal of Laser Micro/Nanoengineering, 9(2), p.137 - 142, 2014/06
Times Cited Count：5 Percentile：29.55(Nanoscience & Nanotechnology)Femtosecond laser ablation processes on platinum, gold, and tungsten were observed by the single shot pump and probe reflective imaging using a soft X-ray laser probe. To avoid the timing error due to the jitter, we adopted a posteriori correction technique by simultaneous measurement of timing between the pump and probe pulses for every single shot, using a soft X-ray streak camera. A clear difference was found in the temporal behavior of the dynamical response of the soft X-ray reflectivity depending on the irradiated laser fluence in these three materials. On the other hand, the narrow dark rings were found in Pt and W, while an additional bright ring was found outside the dark disk in Au. Our result gives the experimental data comparable with various numerical simulations.
-methyltyrosine (FAMT) uptake on PET in patients with oesophageal cancerSuzuki, Shigemasa*; Kaira, Kyoichi*; Ohshima, Yasuhiro; Ishioka, Noriko; Soda, Makoto*; Yokobori, Takehiko*; Miyazaki, Tatsuya*; Oriuchi, Noboru*; Tominaga, Hideyuki*; Kanai, Yoshikatsu*; et al.
British Journal of Cancer, 110(8), p.1985 - 1991, 2014/04
Times Cited Count：24 Percentile：60.43(Oncology)Nishikino, Masaharu; Baba, Motoyoshi*; Suemoto, Toru; Hasegawa, Noboru; Ishino, Masahiko; Kaihori, Takeshi; Kawachi, Tetsuya; Yamagiwa, Mitsuru
X-Ray Lasers 2012; Springer Proceedings in Physics, Vol.147, p.199 - 202, 2014/00
Times Cited Count：0 Percentile：0(Engineering, Electrical & Electronic)The dynamical processes of the laser-induced surface modifications such as laser ablation come to attract much attention for the micro processing by the ultra-short laser pulse. It is difficult to observe these phenomena directly, because they are non-repetitive, unrepeatable, and occur very rapidly (pico-second) in a very small (micron) area. In order to observe the detailed laser-ablation process, we have developed the proto-type reflected soft X-ray microscopy using the Fresnel zone plate. The experimental setup and spatial resolution of the X-ray microscopy will be presented.
Hasegawa, Noboru; Ochi, Yoshihiro; Kawachi, Tetsuya; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Kaihori, Takeshi; Morita, Toshimasa; Sasaki, Akira; Terakawa, Kota*; et al.
X-Ray Lasers 2012; Springer Proceedings in Physics, Vol.147, p.117 - 120, 2014/00
Times Cited Count：0 Percentile：0(Engineering, Electrical & Electronic)We have developed the femto-second laser pump and soft X-ray laser probe system in order to observe the dynamical processes of the femto-second laser ablation. By using this system, we succeed to obtain the temporal evolution of the soft X-ray reflectivity from the laser induced Pt surface. The results lead that the rate of decrease in the reflectivity of the probe beam has a non-linear relation with the pump laser fluence.
Yuri, Yosuke; Ishizaka, Tomohisa; Yuyama, Takahiro; Ishibori, Ikuo; Okumura, Susumu; Kitamura, Akane; Yamaki, Tetsuya; Sawada, Shinichi
Proceedings of 1st International Beam Instrumentation Conference (IBIC 2012) (Internet), p.531 - 533, 2013/06
Tomita, Takuro*; Yamamoto, Minoru*; Hasegawa, Noboru; Terakawa, Kota*; Minami, Yasuo*; Nishikino, Masaharu; Ishino, Masahiko; Kaihori, Takeshi*; Ochi, Yoshihiro; Kawachi, Tetsuya; et al.
Optics Express (Internet), 20(28), p.29329 - 29337, 2012/12
Times Cited Count：19 Percentile：64.97(Optics)Pump and probe reflective imaging using a soft X-ray laser probe was applied to the observation of the early stage of femtosecond laser ablation process on platinum. In strongly excited area, drastic and fast reflectivity drop was observed. In moderately excited area, the decay of the reflectivity is slower than that in the strongly excited area, and the reflectivity reaches its minimum at t = 160 ps. In weakly excited area, laser-induced reflectivity change was not observed. These results give the critical information about the femtosecond laser ablation.
Shamsuzzaman, M.*; Horie, Tatsuro*; Fuke, Fusata*; Kai, Takayuki*; Zhang, B.*; Matsumoto, Tatsuya*; Morita, Koji*; Tagami, Hirotaka; Suzuki, Toru; Tobita, Yoshiharu
Proceedings of 8th Japan-Korea Symposium on Nuclear Thermal Hydraulics and Safety (NTHAS-8) (USB Flash Drive), 10 Pages, 2012/12
Investigation on sedimentation behavior of debris is important to evaluate the sequence of core disruptive accident in SFR. To clarify this behavior, a series of experiments was performed by gravity driven discharge of solid debris from a nozzle into a water pool. The discharged debris accumulates on the collector plate at the bottom, forming either a Gaussian-type convex or ring-type concave mound depending on the experiment parameters. Three types of spherical debris with three diameters are employed to study the effect of experiment parameters on mound height of debris bed. During the experiment, mound height becomes decreasing with nozzle diameter and increasing with debris volume, which exhibits descending tendency in asymmetrical fashion with density variation and an unalike variation in mound height was observed with debris diameter. An empirical model was developed applying dimensional analysis to predict the variation in mound height of debris bed during sedimentation process.
Kawachi, Tetsuya; Hasegawa, Noboru; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Oba, Toshiyuki; Kaihori, Takeshi; Kishimoto, Maki; Ochi, Yoshihiro; Tanaka, Momoko; et al.
X-Ray Lasers 2010; Springer Proceedings in Physics, Vol.136, p.15 - 24, 2011/12
This paper reviews recent improvement in the source development of laser-driven X-ray lasers and the applications in the research fields of material science, laser processing, X-ray imaging, and radiation damage in biological cells. In the application for material science, we have firstly observed temporal correlation between the domain structures of ferro-electric substance under the Curie temperature. In the laser processing, new X-ray laser interferometer reveals us the nano-scale surface distortion of substance pumped by a femto-second optical pulse. In the X-ray diffraction image, we have taken several static images of micro-structure of samples: now we are trying to extend the objective to nano-scale dynamics using pump and probe method. In the radiation damage of biological cells, we observed double strand break in DNA using X-ray laser exposure; this results are compared with the case using incoherent several KeV X-ray exposure.
Hasegawa, Noboru; Ochi, Yoshihiro; Kawachi, Tetsuya; Terakawa, Kota*; Tomita, Takuro*; Yamamoto, Minoru; Nishikino, Masaharu; Oba, Toshiyuki; Kaihori, Takeshi; Imazono, Takashi; et al.
X-Ray Lasers 2010; Springer Proceedings in Physics, Vol.136, p.353 - 358, 2011/12
The understanding of the dynamics of the initial process is important for the micro processing and welding by the ultra-short laser pulse. The X-ray laser is suitable for probing this initial process because it has short wavelength (Ni-like Ag, 13.9 nm) and short duration (7 ps). For this investigation, the origin of time of the pumping pulse is quite important. In this study, we used the scintillation plate and the plasma gate technique to realize the spatial and temporal synchronization of the pump and probe pulses. For the spatial alignment, a CsI scintillation plate that was set at the sample position was illuminated by both the X-ray laser pulse, and the fluorescence light were detected by the CCD camera. For the temporal synchronization, we set a thin foil at the sample position. We measured the transmission of the X-ray laser while changing a temporal delay of the pumping laser with respect to the time of X-ray laser pulse to obtain the origin of the irradiation time.
Hasegawa, Noboru; Ochi, Yoshihiro; Kawachi, Tetsuya; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Kaihori, Takeshi; Sasaki, Akira; Terakawa, Kota*; Minami, Yasuo*; et al.
Proceedings of SPIE, Vol.8140, p.81400G_1 - 81400G_8, 2011/10
Times Cited Count：3 Percentile：82.2(Engineering, Electrical & Electronic)We have developed a soft X-ray laser (SXRL) interferometer capable of the single-shot imaging of nano-scaled structure dynamics. The interferometer consisted of the reflection optics including double Lloyd's mirrors and focusing optics, and the interference fringes are produced on the detector surface. By using this interferometer, the initial stage (
50 ps) of the ablation process of the Pt surface pumped by a 70 fs Ti:Sapphire laser pulse was observed. The expansion speed of the surface estimated from the result (34 nm/50 ps) indicated that the nano-bubble structures were formed in the initial stage of the ablation. In order to observe the detailed dynamics, the temporal synchronization between the pump and probe pulses was improved to be 3 ps by adopting a portion of the SXRL and pump beams as the time fiducials, to which the pump and probe timing was adjusted by using the X-ray streak camera.
Yamamoto, Minoru; Hasegawa, Noboru; Terakawa, Kota*; Umeda, Yoshifumi*; Tomita, Takuro*; Ochi, Yoshihiro; Nishikino, Masaharu; Ishino, Masahiko; Imazono, Takashi; Kaihori, Takeshi; et al.
Proceedings of 12th International Symposium on Laser Precision Microfabrication (LPM 2011) (Internet), 4 Pages, 2011/06
Femtosecond lasers have been used for material processing. However, the physical processes responsible for femtosecond laser ablation have not been understood completely. These processes involve melting, vaporization, re-solidification or ablation, which occur in a very short time from pico- to nano-seconds. To understand the physical processes, it is essential to reveal the dynamics of ultrafast surface morphological change after laser irradiation. At JAEA, the laser-driven plasma soft X-ray laser (SXRL) that has extremely high spatial and spectral purity was constructed. It delivers soft X-ray photons at 89.2 eV (13.9 nm) with a photon number of exceeding 
, which is sufficient to obtain a single shot interferogram. By using this system, the soft X-ray laser interferometer with the lateral resolution of 1.8 
m and a depth resolution of 1 nm was developed. We report on demonstration of time-resolved measurement of femtosecond-laser ablation dynamics by using the soft X-ray laser interferometer.
Nakagawa, Sho*; Hori, Fuminobu*; Chimi, Yasuhiro; Ishikawa, Norito; Kitagawa, Michiharu*; Oshima, Ryuichiro*; Tobita, Toru; Taniguchi, Ryoichi*; Suzuki, Masahide; Iwase, Akihiro*
Nuclear Instruments and Methods in Physics Research B, 257(1-2), p.397 - 401, 2007/04
Times Cited Count：4 Percentile：35.71(Instruments & Instrumentation)Supersaturated Fe-1.2wt.%Cu alloys were irradiated with 200-MeV Xe and 200-MeV Au ions at elevated temperatures. To make an irradiated region and an unirradiated region in a specimen, a masking plate was put on the specimen during the irradiation. After the irradiation, the hardness was measured by using a conventional microhardness tester or a nano-indenter. We have found that the hardness only in irradiated region increases by the irradiation. The boundary of irradiated and unirradiated regions can be clearly identified by the difference in hardness. The present result implies that swift heavy ion irradiation can be used for the local modification of hardness in supersaturated alloys.
Chikazawa, Yoshitaka; Okano, Yasushi; Hori, Toru*; Okubo, Yoshiyuki*; Shimakawa, Yoshio*; Tanaka, Toshihiko*
Journal of Nuclear Science and Technology, 43(8), p.829 - 843, 2006/08
Times Cited Count：4 Percentile：30.68(Nuclear Science & Technology)In phase II of the feasibility study of commercialized fast reactor cycle systems, we make a concept of a small sodium cooled reactor for a power source of a city with various requirements, such as, safety and economical competitiveness. Various reactor concepts are surveyed and a tank type reactor whose intermediate heat exchanger and primary main pumps are arranged in series is selected. In this study, a compact long life core and a simple reactor structure designs are pursued. The core type is three regional Zr concentration with one Pu enrichment core, the reactor outlet temperature achieves 550
C and the reactor electric output increases from 150MWe to 165MWe. The construction cost is much higher than the economical goal in the case of FOAK. But the construction cost in the case of NOAK is estimated to be 85.6% achieving the economical goal.
Chikazawa, Yoshitaka; Kisohara, Naoyuki; Hishida, Masahiko; Fujii, Tadashi; Konomura, Mamoru; Ara, Kuniaki; Hori, Toru*; Uchida, Akihito*; Nishiguchi, Yohei*; Nibe, Nobuaki*
JAEA-Research 2006-049, 75 Pages, 2006/07
JAEA-Research-2006-049.pdf:4.55MB
In the feasibility study on commercialized fast breeder cycle system, a medium scale sodium cooled reactor with 750MW electricity has been designed. In this study, EMPs are applied to the secondary sodium main pump. The EMPs type is selected to be an annular linear induction pump (ALIP) type with double stators which is used in the 160m
/min EMP demonstration test. The inner structure and electromagnetic features are decided reviewing the 160m/min EMP. Two dimensional electromagnetic fluid analyses by EAGLE code show that Rms (magnetic Reynolds number times slip) is evaluated to be 1.08 which is less than the stability limit 1.4 confirmed by the 160m/min EMP test, and the instability of the pump head is evaluated to be 3% of the normal operating pump head. Since the EMP stators are cooled by contacting coolant sodium duct, reliability of the inner structures are confirmed by temperature distribution and stator-duct contact pressure analyses. Besides, a power supply system, maintenance and repair feature and R&D plan of EMP are reported.
Chikazawa, Yoshitaka; Usui, Shinichi; Konomura, Mamoru; Sadahiro, Daisuke*; Tozawa, Katsuhiro*; Hori, Toru*; Toda, Mikio*; Kotake, Shoji*
Proceedings of 14th International Conference on Nuclear Engineering (ICONE-14) (CD-ROM), 7 Pages, 2006/07
A seismic analysis has been performed showing that the seismic interaction between the UIS and the FHM can be avoided adopting gapless bearings at the FHM arm joint. An angular contact ball bearing is suitable for the new FHM since it can eliminate gaps by preload pressure. A major problem of the FHM bearings is lubrication since the contact pressure between steel rings and ball increases because of ball bearing. Additionally, FHM operating temperature is about 200 deg-C and normal grease is not applicable under argon gas with sodium vapor. A endurance test with 1/10 scale bearings in the air has been performed to show applicability of angular contact ball bearings to the FHM arm joint. The results with 20,000 cycle showed that bearings with combination of MoS coating steel rings and ceramics balls can be tolerable as the FHM operating condition. A real scale bearing test in argon gas with sodium vapor has also been demonstrated to reveal bearing size and sodium vapor effects.
Kobayashi, Toru*; Harata, Yasuo*; Matsufuji, Naruhiro*; Hasegawa, Tomoyuki*; Endo, Akira; Moribayashi, Kengo; Akahane, Keiichi*; Uehara, Shuzo*; Imahori, Yoshio*; Kato, Yo*; et al.
JAEA-Review 2006-002, 101 Pages, 2006/02
JAEA-Review-2006-002.pdf:5.53MB
This report provides an analysis of the results of the survey conducted among field experts regarding the data on atoms, molecules, and atomic nuclei used in medical applications. The important results are summarized as follows: First, the importance of the basic data for disciplines involved in medical research, i.e. physics and engineering, chemistry, pharmacology, biology, and the related data which are applied directly in medicine were identified. The related data are of greater importance in direct medical application compared to conventional basic data. Therefore, the data related to biology should be prepared in consideration of their convenient usage. Second, regarding the fundamental data on atoms, molecules and atomic nuclei related to medicine, the present data was able to approximately cope with the demands of many medical cases that needed data on quality, quantity, precision, etc. However, we found situations particularly in the IT community where comprehensively organized data was urgently needed. The data to be used for practical implementation must contain the specialized data for medical physics and biology. Finally, the significance of the continuity in the planned completion of the basic data was confirmed for the development of the associated fields. The expansion and completion of basic data should be done continuously and effectively while considering the limitation in resources and manpower.
