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Nakashima, Satoru*; Kirino, Yusuke*; Nishiyama, Naoki*; Tonoue, Ryota*; Yokoyama, Tadashi*; Nagasawa, Makoto*; Harui, Rika*; Walker, C.; Sasamoto, Hiroshi
no journal, ,
Cementitious grout material will be used to reduce groundwater inflow into the repository of high level radioactive waste. High pH solution derived from cementitious grout material may cause alteration of rock mass by grout-rock interactions. With regard to evaluation of radionuclide migration, it is important to evaluate the long-term behavior of rock mass affected by grout-rock interactions since such altered rock mass potentially affects on migration behavior (e.g., diffusion and sorption) of radionuclide. This study presents the results of identification for trace secondary minerals (alteration products) by (micro)infrared spectroscopy and determination of reaction rate constants of formation for secondary minerals.
Esaka, Fumitaka; Magara, Masaaki; Suzuki, Daisuke; Miyamoto, Yutaka; Lee, C. G.; Kimura, Takaumi
no journal, ,
In this study, a combination of chemical separation and inductively coupled plasma - mass spectrometry (ICP-MS) is applied to the analysis of individual plutonium particles. Prior to the isotope ratio analysis with ICP-MS, individual plutonium particles in samples were identified by using scanning electron microscope (SEM) and transferred to each Si chip by a micro-manipulator attached to the SEM system. After removed from the SEM chamber, each particle was dissolved with HF-HNO
solution. An anion exchange method was applied to separate Pu and Am for subsequent isotope ratio analysis with ICP-MS. As a result, the plutonium isotope ratios in individual particles with the diameter less than 1 micrometer could be determined with good accuracy. In this presentation, the analytical results of mixed uranium-plutonium particles will also be presented.
Otsuka, Ichiro*; Tanaka, Tadao; Inada, Daisuke*
no journal, ,
The experiments to elucidate physico-chemical behavior of iron in the low oxygen and reducing condition of deep underground geology have been performed carefully in the glove box controlling oxygen concentration. It is necessary to protect oxidation by oxygen for XRD measurement of Fe(II) compounds that easily oxidize in atmosphere. In the present research, the method to measure XRD of the Fe(II) compounds was proposed. In the argon gas circulating type glove box controlled in oxygen concentration less than 1 ppm, Fe(OH)
was prepared. Resulting Fe(OH) was pasted to surface of glass cell, and was sealed by Kapton film. The glass cell was taken out into atmosphere from a glove box and XRD measurement was performed. As to the cell sealed up by Kapton film, only peaks of Fe(OH) was observed. This experimental result shows that the XRD measurement of Fe(OH) in atmosphere is possible by sealing up the sample on glass cell by Kapton film.
Okamura, Hiroyuki; Shimojo, Kojiro; Ikeda, Atsushi*; Saito, Takumi*; Aoyagi, Noboru; Hirayama, Naoki*; Umetani, Shigeo*; Imura, Hisanori*; Naganawa, Hirochika
no journal, ,
Yamazaki, Hideo*; Ishizu, Naoto*; Kokubu, Yoko
no journal, ,
Our country has experienced radioactive pollution of many times, such as atomic bombs of Hiroshima and Nagasaki, global fallout from nuclear weapon tests and the accident of Chernobyl until now. The radioactive pollution has been released even in now from the Fukushima Nuclear Power Plant, which was damaged by the Eastern Japan earthquake disaster. We report the historical trend of radioactive pollution in our country and the actual condition of present incident. We analyzed soils and sediment cores collected in Nagasaki and determined the spatiotemporal distribution of the radionuclide released from the Nagasaki atomic bomb. Some surface soils in Fukushima City (55km from nuclear power plant) was measured by 
-ray spectrumetry and some radionuclides such as 
I and 
Cs were detected.