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Oizumi, Akito; Sugawara, Takanori; Sagara, Hiroshi*
Annals of Nuclear Energy, 169, p.108951_1 - 108951_9, 2022/05
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Research and development of the partitioning and transmutation (P&T) cycle with accelerator-drive systems (ADSs) transmuting minor actinides separated from the commercial cycles have been continuously conducted to reduce the amount of high-level radioactive waste contained in spent fuel discharged from nuclear power plants. Because the chemical form and composition of the fuels are different from those of the current commercial cycles, it is necessary to examine the inspection goal of the safeguards (SGs) and the design level of physical protections (PPs) that are required for the P&T cycle. In this study, the material attractiveness was evaluated assuming the theft or diversion of fuel assemblies from the fuel storage pool of the ADS facility in terms of nuclear security and non-proliferation. According to the results, quantitative components based on the fundamental fuel property were created as an important factor to decide the inspection goal for SGs and the design level for PPs required for the ADS facility. Additionally, the attractiveness of mixed oxide (MOX) fuel assemblies stored in the commercial boiling water reactor (BWR) facility was compared with that of the ADS. With regard to nuclear security, the ADS fuel was less attractive than the BWR MOX in every cycle. Regarding nuclear non-proliferation, the ADS fuel assembly had less attractive plutonium (Pu) than the BWR MOX, and the uranium (U) in the ADS fuel assembly was as attractive as (or slightly more attractive than) that of the BWR MOX owing to low spontaneous fission neutron. Furthermore, new issues were identified through this evaluation. With the current regulations, it was difficult to decide whether the ADS fuel before irradiation should be treated as fresh or spent, because the ADS fresh fuel contained more transuranium and rare earth than U and contained U whose main component was U-234 instead of U-238.
Nakano, Keita; Iwamoto, Hiroki; Nishihara, Kenji; Meigo, Shinichiro; Sugawara, Takanori; Iwamoto, Yosuke; Takeshita, Hayato*; Maekawa, Fujio
JAEA-Research 2021-018, 41 Pages, 2022/03
JAEA-Research-2021-018.pdf:2.93MB
Neutronic analysis of beam window of the Accelerator-Driven System (ADS) proposed by Japan Atomic Energy Agency (JAEA) has been conducted using PHITS and DCHAIN-PHITS codes. We investigate gas production of hydrogen and helium isotopes in the beam window, displacement per atom of beam window material, and heat generation in the beam window. In addition, distributions of produced nuclides, heat density, and activity are derived. It was found that at the maximum 12500 appm H production, 1800 appm He production, and damage of 62.1 DPA occurred in the beam window by the ADS operation. On the other hand, the maximum heat generation in the beam window was 374 W/cm
. In the analysis of LBE, 
Bi and 
Po were found to be the dominant nuclides in decay heat and radioactivity. Furthermore, the heat generation in the LBE by the proton beam was maximum around 5 cm downstream of the beam window, which was 945 W/cm.
of uranium in ADS fuel assemblyOizumi, Akito; Sugawara, Takanori; Sagara, Hiroshi*
Dai-42-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2021/11
Research and development of partitioning and transmutation cycle with accelerator drive systems (ADSs) transmuting minor actinides (MAs) separated from the commercial cycles has been continuously conducted to reduce the high-level radioactive waste (HLW) contained in spent fuel discharged from nuclear power plants. Since the chemical form and composition of the fuels are different from those of the current commercial cycles, it is necessary to examine the inspection goal of the safeguards (SGs) and the design level of physical protections (PPs) which are required for the partitioning and transmutation cycle. In this study, 
of the uranium (U) in the fuel assembly in the fuel storage pool in the ADS facility was evaluated and it was compared with the plutonium (Pu) in the MOX fuel assembly for a general boiling water reactor (BWR). As a result, it made clear that the U in the ADS fuel assembly had equal to or less attractive than the Pu in the BWR MOX fuel assembly. Moreover, a new issue has been extracted. It is difficult to determine whether the ADS fresh fuel should be considered as non-irradiated or irradiated fuel under the current regulatory standards because the ADS fresh fuel contains many MAs, rare-earths, and 
U rich U.
of fuel assembly in early period of burnup cycleOizumi, Akito; Sugawara, Takanori; Sagara, Hiroshi*
Dai-41-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2020/11
Research and development of partitioning and transmutation cycle with accelerator drive systems (ADSs) transmuting minor actinides (MAs) separated from the commercial cycles has been continuously conducted to reduce the high-level radioactive waste (HLW) contained in spent fuel discharged from nuclear power plants. Since the chemical form and composition of the fuels are different from those of the current commercial cycles, it is necessary to examine the accuracy of the safeguards (SGs) and the level of physical protections (PPs) which are required for the partitioning and transmutation cycle. In this study, of the first cycle fuel assemblies (fresh and spent fuels) in the fuel storage pool in the ADS facility was evaluated and it was compared with that of the MOX fuel assemblies (fresh and spent fuels) for a general boiling water reactor (BWR). As a result, it made clear that the fuel storage pool in the ADS facility storing the first cycle fuel assemblies were required the SG detection accuracy and PP level equal to or lower than the MOX fuel assembly of the BWR since the ADS fuel assembly in the first cycle was less attractive than the MOX fuel assembly for the BWR.
Se
ultrathin films on van der Waals ferromagnet CrSiTe
Kato, Takemi*; Sugawara, Katsuaki*; Ito, Naohiro*; Yamauchi, Kunihiko*; Sato, Takumi*; Oguchi, Tamio*; Takahashi, Takashi*; Shiomi, Yuki*; Saito, Eiji; Sato, Takafumi*
Physical Review Materials (Internet), 4(8), p.084202_1 - 084202_6, 2020/08
Times Cited Count：4 Percentile：20.11(Materials Science, Multidisciplinary)Sugawara, Takanori; Eguchi, Yuta; Obayashi, Hironari; Iwamoto, Hiroki; Matsuda, Hiroki; Tsujimoto, Kazufumi
Proceedings of 26th International Conference on Nuclear Engineering (ICONE-26) (Internet), 10 Pages, 2018/07
A new beam window concept for accelerator-driven system (ADS) is investigated by changing the design condition. The most important factor for the beam window design is the proton beam current. The design condition will be mitigated if the proton beam current will be reduced. To reduce the proton beam current, a subcriticality adjustment rod (SAR) which was a B
C control rod was employed and neutronics calculations were performed by ADS3D code. The results of the neutronics calculation indicated that the proton beam current was reduced from 20mA to 13.5mA by the installation of SARs. Based on the mitigated calculation condition, the investigation of the beam window was performed by the couple analyses of the particle transport, the thermal hydraulics and the structural analysis. Through these coupled analyses, more feasible beam window concept which was the hemispherical shape, the outer diameter = 470mm, the thickness at the top = 3.5mm and factor of safety =9 was presented.
P
Ishii, Kenji; Tsutsui, Satoshi*; Hao, L.*; Hasegawa, Tomoo*; Iwasa, Kazuaki*; Tsubota, Masami; Inami, Toshiya; Murakami, Yoichi*; Saha, S. R.*; Sugawara, Hitoshi*; et al.
Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.e178 - e180, 2007/03
PrRuP shows a metal-insulator (MI) transition at 
62 K accompanied by a structural phase transition. Because LaRuP without 
electrons does not shows the MI transition, electrons in the Pr atom plays an important role in the transition. In order to elucidate a modulation of electronic states of Pr, we have carried out a resonant X-ray scattering study of PrRuP at Pr 
- and 
-edges. Below 
, resonant signal at the absorption main-edge was successfully observed at the superlattice reflections of the modulation vector 
in addition to the energy-independent component from the lattice distortion. Because the reflection contains the difference of anomalous scattering factors between two Pr atoms in the unit cell, two different electronic states are actually ordered below 
. Furthermore we found that the polarization of X-ray is mostly unrotated even at the resonance, which indicates that the resonant scattering in PrRuP is almost isotropic.
PIshii, Kenji; Inami, Toshiya; Murakami, Yoichi; Hao, L.*; Iwasa, Kazuaki*; Kogi, Masafumi*; Aoki, Yuji*; Sugawara, Hitoshi*; Sato, Hideyuki*; Imada, Shin*; et al.
Physica B; Condensed Matter, 329-333(1-4), p.467 - 468, 2003/05
Times Cited Count：6 Percentile：35.59(Physics, Condensed Matter)Resonant x-ray scattering study was carried out to investigate an anomalous ordered state (
= 6.5 K) in the filled skutterudite PrFeP. At the Pr-
absorption edge, we observed resonant features in 
= odd reflections, which are forbidden in the 
structure above . Because these reflections contain the difference of anomalous scattering factor between two Pr atoms in the unit cell, and the ordered state is attributed to the ordering of two different electronic states of Pr.
Sugawara, Masaaki*; Maruyama, Toru*; Kambara, Hiroshi*
JNC TJ7420 2005-047, 79 Pages, 2003/03
JNC-TJ7420-2005-047.pdf:12.71MB
Configuration and structure of the ore veins of the Toyoha mine, which occur in faults, were studied with the purpose of developing methods for investigating the effect of fault movement to groundwater flow. Information on the shape of the veins were acquired and analyzed. Plane vein maps in some levels and cross sections of four representative vein systems (Tajima-Harima, Izumo-Shinano, Soya, Sorachi) of the Toyoha ore deposit were scanned, and three-dimensional features of vein distributions were recorded as image data. Morphological characteristics of typical veins of the Toyoha ore deposit were extracted from vein maps, geological and mineralogical cross sections and vein sketches. A tendency of vein-shape changes is recognized from the upper to the lower parts; cymoid curve with strong lensing, gentle cymoid curve with relatively constant width, linear vein with relatively constant width in ascending order of depth. This is thought to be a morphological characteristics of shear fracture formed in correspondence with increase of confining pressure. Distribution of vein trace length of the Toyoha mine exist within the range of uncertainty in the figure between fracture trace length and cumulative number of fractures indicated by Ohtsu (2001). Thus, accumulated number of fracture trace length is thought to be in linear relation irrespective of size, region and rock ype.
Ghimile, H. N.*; Ishijima, Yoji*; Sugawara, Takayuki*; Nakama, Shigeo
Shigen To Sozai, 119(9), 0 Pages, 2003/00
Most in-situ data on rock stresses are from hard or moderately hard rock. It is necessary to develop a stress measurement method for soft rock, toward obtaining the in-situ stress state in such rock. We developed a stress meter that measures seven components of diametrical deformation and axial deformation in a pilot borehole during overcoring and records the measurements on a small data logger installed within it. From these deformation data, three-dimensional stress states in rock are determined using the observation equation derived from the analytical elastic solution. The stress meter is inserted into a 40-mm pilot borehole that can range in water content from dry to completely wet. The advantages of this stress meter are its smallness, ease of use, reusability, ability to measure at any borehole depth, and efficiency, since very little time is required for insertion and withdrawal and no time is needed to shift from insertion to overcoring. Moreover, elastic properties of the roc
Hayashi, Shinichiro; ; *; *; *
Computer Physics Communications, 125, p.60 - 74, 2000/00
Times Cited Count：7 Percentile：35.85(Computer Science, Interdisciplinary Applications)None
Sugawara, Satoru; ;
Proceedings of 1st Korea-Japan Symposium on Nuclear Thermal Hydrqulics and Safety (NTHAS 98), p.335 - 341, 1998/00
None
; *; *; *; ;
Review of Scientific Instruments, 50(11), p.1452 - 1457, 1979/00
no abstracts in English
*; ; *; *;
JAERI-M 7612, 11 Pages, 1978/03
no abstracts in English
PIshii, Kenji; Tsubota, Masami; Inami, Toshiya; Tsutsui, Satoshi*; Hao, L.*; Hasegawa, Tomoo*; Iwasa, Kazuaki*; Murakami, Yoichi; Sugawara, Hitoshi*; Saha, S. R.*; et al.
no journal, ,
PrRuP shows a metal-insulator (MI) transition at 62 K accompanied by a structural phase transition. Because LaRuP without electrons does not shows the MI transition, electrons in the Pr atom plays an important role in the transition. In order to elucidate a modulation of electronic states of Pr, we have carried out a resonant X-ray scattering study of PrRuP at Pr - and -edges. Below , resonant signal at the absorption main-edge was successfully observed at the superlattice reflections of the modulation vector in addition to the energy-independent component from the lattice distortion. Because the reflection contains the difference of anomalous scattering factors between two Pr atoms in the unit cell, two different electronic states are actually ordered below . Furthermore we found that the polarization of X-ray is mostly unrotated even at the resonance, which indicates that the resonant scattering in PrRuP is almost isotropic.
鳥居 建男; 佐藤 優樹
小澤 慎吾*; 菅原 洋*
JP, 2018-173023 Patent licensing information Patent publication (In Japanese)
【課題】地表の広い範囲における放射性物質の位置を高精度で検出して3次元表示可能とする。 【解決手段】3次元位置を検出可能な移動体(ドローン10)に搭載された放射線検出器(コンプトンカメラ20)を用いて放射線を測定し、前記移動体(10)の移動に伴って得られる複数位置での前記放射線検出器(20)による測定結果と前記移動体(10)の3次元位置情報とを用いることによって、放射線分布の3次元マップを作成し、該放射線分布の3次元マップを、3次元の地形データ又は航空写真と重ね合せて表示する際に、放射線検出器(20)による放射線測定値を、地表(6)面の単位面積毎の測定にかかった時間に応じて時間補正する。更に、放射線検出器(20)と地表(6)面の距離に応じて距離補正したり、放射線検出器(20)に対する放射線の入射角度に応じて角度補正したりすることもできる。
