Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Sakuma, Kazuyuki; Kitamura, Akihiro; Malins, A.; Kurikami, Hiroshi; Machida, Masahiko; Mori, Koji*; Tada, Kazuhiro*; Kobayashi, Takamaru*; Tawara, Yasuhiro*; Tosaka, Hiroyuki*
Journal of Environmental Radioactivity, 169-170, p.137 - 150, 2017/04
Times Cited Count：26 Percentile：58.89(Environmental Sciences)This paper describes watershed modeling of catchments surrounding the Fukushima Dai-ichi Nuclear Power Plant to understand radio-cesium redistribution by water flows and sediment transport. We extended our previously developed three-dimensional hydrogeological model of the catchments to calculate the migration of radio-cesium in both sediment-sorbed and dissolved forms. The simulations cover the entirety of 2013, including nine heavy rainfall events, as well as Typhoon Roke in September 2011. Typhoons Man-yi and Wipha were the strongest typhoons in 2013 and had the largest bearing on radio-cesium redistribution. The simulated 
Cs discharge quantities over the nine events in 2013 are in good agreement with field monitoring observations. Deposition mainly occurs on flood plains and points where the river beds broaden in the lower basins, and within dam reservoirs along the rivers. Differences in Cs discharge ratios between the five basins are explained by differences in the initial fallout distribution within the basins, the presence of dam reservoirs, and the input supply to watercourses. It is possible to use these simulation results to evaluate future radioactive material distributions in order to support remediation planning.
Kitamura, Akihiro; Kurikami, Hiroshi; Sakuma, Kazuyuki; Malins, A.; Okumura, Masahiko; Machida, Masahiko; Mori, Koji*; Tada, Kazuhiro*; Tawara, Yasuhiro*; Kobayashi, Takamaru*; et al.
Earth Surface Processes and Landforms, 41(12), p.1708 - 1726, 2016/09
Times Cited Count：19 Percentile：52.56(Geography, Physical)Sediment erosion and transport processes that are considered to be important in predicting the future radioactive material distribution through sediment-sorbed form in Fukushima Prefecture are simulated. Since large portion of the sediment is considered to be supplied into the rivers, it is important to trace their migration process in terms of each river basin. We choose five river basins, namely the Odaka, the Ukedo, the Maeda, the Kuma, and the Tomioka, from north to south, because of their importance in contamination aspects and prediction studies. The results are summarized as comprehensive dataset of sediment migration for particular river basins in typical typhoon events that account for the most of annual soil erosion. Detail calculations implemented for the amount of sediment supplied in to the river, deposited on river and dam beds, and exported to the ocean.
Imai, Makoto*; Sataka, Masao; Kitazawa, Shinichi; Komaki, Kenichiro*; Kawatsura, Kiyoshi*; Shibata, Hiromi*; Tawara, Hiroyuki*; Azuma, Toshiyuki*; Kanai, Yasuyuki*; Yamazaki, Y.*
Nuclear Instruments and Methods in Physics Research B, 193(1-4), p.674 - 679, 2002/06
Times Cited Count：5 Percentile：33.61(Instruments & Instrumentation)no abstracts in English
ions excited through He gas and C-foil targetsSataka, Masao; Imai, Makoto*; Kawatsura, Kiyoshi*; Komaki, Kenichiro*; Tawara, Hiroyuki*; Vasilyev, A.*; Safronova, U. I.*
Physical Review A, 65(5), p.052704_1 - 052704_11, 2002/05
Times Cited Count：13 Percentile：51.69(Optics)no abstracts in English
, C
H
, CH, CH, C
H
, and CHShirai, Toshizo; Tabata, Tatsuo*; Tawara, Hiroyuki*; Ichikawa, Yukikazu*
Atomic Data and Nuclear Data Tables, 80(2), p.147 - 204, 2002/03
Times Cited Count：75 Percentile：93.48(Physics, Atomic, Molecular & Chemical)Cross sections for 138 processes of hydrocarbons in collisions with electrons, based on available literature sources, are critically compiled. The leterature has been surveyed to September 2000. A short comment is given for each measurement. The recommended data sets are presented in separate graphs for each process. Analytic fits to the recommended cross sections are also presented.
Si
ions excited through a thin C-foil targetSataka, Masao; Imai, Makoto*; Kawatsura, Kiyoshi*; Komaki, Kenichiro*; Tawara, Hiroyuki*; Vasilyev, A.*; Safronova, U. I.*
Journal of Physics B; Atomic, Molecular and Optical Physics, 35(2), p.267 - 281, 2002/01
Times Cited Count：3 Percentile：19.43(Optics)no abstracts in English
, and HO relevant to edge plasma impuritiesShirai, Toshizo; Tabata, Tatsuo*; Tawara, Hiroyuki*
Atomic Data and Nuclear Data Tables, 79(1), p.143 - 184, 2001/09
Times Cited Count：62 Percentile：92.15(Physics, Atomic, Molecular & Chemical)no abstracts in English
Shimada, Michiya; Hosogane, Nobuyuki; Itami, Kiyoshi; Takamura, Shuichi*; Oyabu, Nobuyoshi*; Tawara, Hiroyuki*; Hatayama, Akiyoshi*
Purazuma, Kaku Yugo Gakkai-Shi, 76(1), p.41 - 63, 2000/01
no abstracts in English
Kitazawa, Shinichi; Sataka, Masao; Tawara, Hiroyuki*; Imai, Makoto*; Shibata, Hiromi*; Komaki, Kenichiro*; Azuma, Toshiyuki*; Kawatsura, Kiyoshi*; Kanai, Yasuyuki*
Atomic Collision Research in Japan, No.25, p.65 - 67, 1999/00
no abstracts in English
