Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Iwatsuki, Teruki; Ishii, Eiichi; Honda, Teruyuki*
no journal, ,
Long-term evolution of hydrochemical condition and trace elements are inferred at Horonobe area, Japan. Hydrochemical conditions such as salinity, pH and Eh of groundwaters were estimated in each hydrogeological domain. On the other hand, concentration of trace elements in each hydrogeological domain are homogenious. This suggests that the trace elements had not migrated during long-term evolution of hydrochemical environments.
Yamamoto, Yuhei; Aosai, Daisuke; Mizuno, Takashi
no journal, ,
no abstracts in English
Aosai, Daisuke; Yoshida, Haruo*; Mizuno, Takashi
no journal, ,
no abstracts in English
Suzuki, Yohei*; Fukuda, Akari*; Kozuka, Mariko*; Ishimura, Toyoho*; Tsunogai, Urumu*; Hagiwara, Hiroki; Mizuno, Takashi
no journal, ,
no abstracts in English
Mizuno, Takashi; Sai, Masataka; Hagiwara, Hiroki; Aosai, Daisuke; Yamamoto, Yuhei
no journal, ,
no abstracts in English
produced through SOM decompositionsMoriya, Koichi*; Moriizumi, Jun*; Yamazawa, Hiromi*; Koarashi, Jun; Atarashi-Andoh, Mariko
no journal, ,
no abstracts in English
Oku, Shunsuke*; Otosaka, Shigeyoshi; Minakawa, Masayuki*; Minami, Hideki*; Noriki, Shinichiro*
no journal, ,
Autochthonous Ba (Ba-xs) in seawater is enriched in particulate materials by marine biota and settles down to the seabed. Therefore, Ba-xs is known as a proxy of export production in the surface ocean. However, it is necessary to discuss the effect of lateral transport of Ba-xs for the accurate estimation of the export flux. In this study, the authors investigated the effect of lateral transport of Mn-xs from a sediment trap experiment in the Japan Sea. Particulate fluxes of Ba-xs showed a positive relationship between flux of autochthonous Mn (Mn-xs). The flux of Mn-xs was higher in winter and it might be caused by the lateral transport of particulate materials from the shelf regions. The results indicated that Ba-xs is transported laterally and the effect was on a par with the sinking of biogenic particles.
Kozai, Naofumi; Onuki, Toshihiko; Iwatsuki, Teruki
no journal, ,
Chemical states of uranyl in deep ground water sampled at Horonobe have been analyzed by SEC-UV-Vis-ICP-MS. Uranium was present as electrical neutral colloids and with Si. These findings suggest that uranium is formed pseudocolloids with Si in deep ground water.
Jiang, M.; Onuki, Toshihiko; Kozai, Naofumi; Tanaka, Kazuya; Suzuki, Yoshinori; Utsunomiya, Satoshi*
no journal, ,
We investigated association of Ce with yeast S. cerevisiae at pH of 3, 4, and 5. SEM analysis showed that nano-sized Ce bearing minerals were developed on the cell surface. TEM and SAED analyses showed that the Ce- bearing mineral is monazite.
Suzuki, Yoshinori; Tanaka, Kazuya; Kozai, Naofumi; Onuki, Toshihiko
no journal, ,
Reduction of U(VI) by Shewanella putrefaciens in the presence of citrate, NTA, and EDTA was examined to elucidate effects of strong complexation agents on the biological reduction. In the control media containing no citrate, NTA, and EDTA, the concentration of dissolved U decreased with time and precipitates were observed. In the presence of citrate, NTA, or EDTA, the reduced species of U(IV) were soluble U(IV)-organic complexes. The initial reduction rate of U(VI) in the citrate media was much slower than those in the NTA and EDTA media. These results indicate that the presence of strong complexation agents affect the chemical species of U(IV) and the reduction rate of U(VI).
Sakamoto, Fuminori; Onuki, Toshihiko; Fujii, Tsutomu*; Iefuji, Haruyuki*
no journal, ,
In this study, we cultured Saccharomyces cerevisiae in media containing Pb or U with adjusted concentration and compared influence of Pb and 4U on the growth of S. cerevisiae. S. cerevisiae grew in media containing 1 
10
or 1 10
M Pb, but did not grow in the medium containing 1 10
M Pb. S. cerevisiae did not grow in the medium containing 1 10 and 1 10 M U. These results indicated that inhibitory effect of U on the growth of S. cerevisiae is greater than that of Pb and that Pb and U obstruct the growth of S. cerevisiae by a different mechanism. S. cerevisiae did not grow in the medium containing 1 10 M natural U, but grew in the medium containing 
U with alpha radioactivity equivalent to 1 10 M natural U. These results indicated that the growth of S. cerevisiae is not influenced by chemotoxicity but radiotoxicity of 1 10 M Pb and U.
Tanaka, Kazuya; Tani, Yukinori*; Onuki, Toshihiko
no journal, ,
no abstracts in English