Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Tc-radiopharmaceuticals obtained from 
Mo produced by 
Mo(n,2n)Mo and fission of 
UHashimoto, Kazuyuki; Nagai, Yasuki; Kawabata, Masako; Sato, Nozomi*; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji*; Ota, Masayuki; Konno, Chikara; Ochiai, Kentaro; et al.
Journal of the Physical Society of Japan, 84(4), p.043202_1 - 043202_4, 2015/04
Times Cited Count：8 Percentile：53(Physics, Multidisciplinary)
2012 FYOchiai, Shoji; Asamori, Koichi; Tokiwa, Tetsuya; Nohara, Tsuyoshi; Matsuoka, Toshiyuki
JAEA-Research 2014-002, 69 Pages, 2014/03
JAEA-Research-2014-002.pdf:7.39MB
The purpose of this study is to examine the analysis techniques and observation techniques required to obtain the seismic data on long-term stability of the geological environment. Through the earthquake observation of about 9 years and the development of seismic network as a case study of Horonobe, we confirmed the observation techniques, such as the effectiveness of the seismograph installation using the pit for a snowy cold environment. The performance of the observation points in a relatively soft ground was about 1 mGal acceleration that can distinguish earthquake from background noise. For analysis technology, we confirmed the valid range of observational data for hypocenter determination. Also, the analysis conditions for improving the hypocenter accuracy by applying the Double-Difference Method (DD method) and Multiplet-clustaring method were confirmed. It was estimated that applicability of these methods is high in the condition that the hypocenters concentrated. The reliability of DD method has been improved by using many data including the observation points near the hypocenter. Analyzed focal mechanisms showed reverse fault of east-west compression. This is consistend with the geological structure and the regional stress field.
Tokiwa, Tetsuya; Sawada, Sumiyuki; Ochiai, Shoji; Miyakawa, Kazuya
Dai-13-Kai Iwa No Rikigaku Kokunai Shimpojiumu Koen Rombunshu (CD-ROM), p.1021 - 1025, 2013/01
In the Horonobe area of Japan, underground facilities have been excavated in soft sedimentary rocks in order to enhance the reliability of relevant technologies for geological disposal of high-level radioactive waste in Japan. Pre-excavation grouting was carried out at 250 to 380 m depth at the location of the planned Ventilation Shaft. After the grouting, the shaft was excavated from 250 to 350 m depth, and fracture mapping was carried out to understand the characteristics of water conductive fractures by focusing on the occurrence of injected grout. Fractures consist mainly of shear fractures, and extension fractures and faults are observed in the shaft. The faults are associated with fault rocks and high continuity. Grout was mainly observed in fractures located on the branching part from faults rather than the fault itself, and therefore high-permeability fractures are not the fault itself (fault core) but fractures located on the branching part in the damage zone of the fault.
Sn strandsOsamura, Kozo*; Machiya, Shutaro*; Tsuchiya, Yoshinori*; Suzuki, Hiroshi; Shobu, Takahisa; Sato, Masugu*; Hemmi, Tsutomu; Nunoya, Yoshihiko; Ochiai, Shojiro*
Superconductor Science and Technology, 25(5), p.054010_1 - 054010_9, 2012/05
Times Cited Count：17 Percentile：57.55(Physics, Applied)
Tc-MDP using Tc separated from Mo produced by Mo(
,2)MoNagai, Yasuki; Hatsukawa, Yuichi; Kin, Tadahiro; Hashimoto, Kazuyuki; Motoishi, Shoji; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke; Sato, Yuichi*; Kawauchi, Yukimasa*; et al.
Journal of the Physical Society of Japan, 80(8), p.083201_1 - 083201_4, 2011/08
Times Cited Count：15 Percentile：65.33(Physics, Multidisciplinary)We have for the first time succeeded to separate Tc from a Mo oxide sample irradiated by accelerator neutrons, and to formulate Tc-methylene diphosphonate (Tc-MDP). Mo, the mother nuclide of Tc, was produced by the Mo(,2)Mo reaction using about 14 MeV neutrons provided at the Fusion Neutronics Source of Japan Atomic Energy Agency. The Tc was separated from Mo by the sublimation method, and its radionuclide purity was confirmed to be higher than 99.99%. The labeling efficiency of Tc-MDP was shown to be higher than 99%. These values exceed the United States Pharmacopeia requirements for a fission product, Mo. Consequently, a Tc radiopharmaceutical preparation formed by using the mentioned Mo can be a promising substitute for the fission product Mo. A longstanding problem to ensure a reliable and constant supply of Mo in Japan can be partially mitigated.
Nohara, Tsuyoshi; Tokiwa, Tetsuya; Ochiai, Shoji
no journal, ,
Evaluation of effect of fault zone is one of the important issues in the geological isolation of high-level radioactive wastes. Based on the result of the geological data in and around the northern Hokkaido Horonobe hill, the outline is arranged about changes of the depositional environment in the past about 3 million years, and the relation with the development process of a fault related fold is considered.
