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Narita, Ayumi; Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Hirao, Norie; Yaita, Tsuyoshi
no journal, ,
no abstracts in English
Asano, Masaharu; Koshikawa, Hiroshi; Yamaki, Tetsuya; Maekawa, Yasunari; Yamaguchi, Susumu*; Yamamoto, Kazuya*; Asazawa, Koichiro*; Yamada, Koji*; Tanaka, Hirohisa*
no journal, ,
no abstracts in English
Ichihara, Akira; Kurosaki, Yuzuru; Yokoyama, Keiichi
no journal, ,
Vibrational and rotational excitation processes were calculated for the CsI molecule in laser fields with two independent computer codes developed on the basis of the wave packet and coupled channel methods in order to study the isotope separation of the long-lived fission product 
Cs. The 4-th order Runge-Kutta method was used in the coupled channel code. In the wave packet code, the fast Fourier transform was applied to compute vibrational motion, and the DVR technique was employed to describe rotational states. It was found that the rotational states can be excited successively by laser pulses in the shape of optical frequency combs and that the vibrational excitation is not induced by the frequency combs.
Haraga, Tomoko; Nakano, Yuta*; Shibukawa, Masami*; Saito, Shingo*; Kameo, Yutaka; Takahashi, Kuniaki
no journal, ,
For the safe disposal of radioactive wastes, a simple and highly sensitive analytical method for actinides in waste samples is required. In this study, a capillary electrophoresis with laser induced fluorescent detection was examined for analysis of neptunium (
Np) and americium (
Am). Applying a pre-capillary complexation technique using several new emissive complexing probes with various chelating moieties, the highly sensitive fluorescent detection of Np and Am was succeeded. In addition, the separation of Np and Am was achieved for a multidentate probe. The detection limit was obtained at mid-ppt levels.
Koswattage, K.; Shimoyama, Iwao; Sekiguchi, Tetsuhiro; Baba, Yuji; Nakagawa, Kazumichi*
no journal, ,
no abstracts in English
Nagaishi, Ryuji; Kumagai, Yuta
no journal, ,
Radiation-induced reactions taking place in aqueous solutions, where both nitrate and platinum group ions (Pd, Rh, Pt, Ru) can be reduced by radiolysis products of water, were studied by product analysis after steady-state irradiation of Co-60 
ray. In aqueous solutions containing alcohols, from which reducing agents are produced, the nitrate and Pt group ions were competitively reduced. The reduction of Pt group ions was enhanced by addition of solid oxides to aqueous solutions.
Saeki, Morihisa; Taguchi, Tomitsugu; Oba, Hironori
no journal, ,
In this work, we have developed a new separation and recovery technique by combining laser-induced particle formation and solvent extraction process.
Lin, M.; Katsumura, Yosuke*; Muroya, Yusa*; Yan, Y.*; Kumagai, Yuta; Nagaishi, Ryuji; Mostafavi, M.*
no journal, ,
Using methyl viologen and 4,4'-bipyridyl as a scavenger of solvated electron in water and methanol, respectively, the time dependent yield of solvated electron in these two solvents has been estimated from room temperature to 300
C. A good agreement between picosecond pulse radiolysis (direct measurement) and scavenging method is demonstrated. These results will be very useful for the understanding of temperature effects on spur reactions.
Shimojo, Kojiro; Mitamura, Hisayoshi; Mouri, Tsuyoshi; Naganawa, Hirochika
no journal, ,
no abstracts in English
Hamakawa, Shotaro; Hasegawa, Shin; Maekawa, Yasunari
no journal, ,
The graft polymers of a graft-type polymer electrolyte membrane consisting of poly(styrenesulfonic acid) (PSSA) attached on thermally stable fluorinated polymer substrates detached from the polymer substrate without decomposition or scission of graft polymer chains. In this work, the molecular weights of detached graft polymers were analyzed by gel permeation chromatography to investigate the mechanism of radiation-induced graft polymerization of styrene into the fluorinated polymer substrates. The number average molecular weight (Mn) of graft polymers seemed to be constant with Mn of about 3500 in the range of grafting degrees between 6 and 86%. Thus, graft polymerization proceeds with quite fast initiation and termination reactions to give a similar Mn of the graft polymers during the whole course of graft polymerizations.
Kumagai, Yuta; Nagaishi, Ryuji; Yamada, Reiji; Muroya, Yusa*; Katsumura, Yosuke*
no journal, ,
In radiolysis of mixture of water and solid oxides, reactions of hydrated electron are considered as a possible source of excess production of H
. In this study transient kinetics of hydrated electron in aqueous solution containing nano-sized colloidal silica was studied using pulse-radiolysis technique. The decay of hydrated electron became slower by the addition of colloidal silica. However in aqueous solution containing 
-butanol, where the reaction of hydrated electron with hydroxyl radical is inhibited, the addition of colloidal silica had no significant effect on the kinetics of hydrated electron. The results suggest that the effect of colloidal silica on the decay of hydrated electron was due to the reaction of colloidal silica with hydroxyl radical. Therefore the coexistence of colloidal silica was not expected to induce an effective reaction pathway to produce H from hydrated electron.
Sato, Tetsuya; Tsukada, Kazuaki; Asai, Masato; Toyoshima, Atsushi; Sato, Nozomi; Li, Z.; Kikuchi, Takahiro; Kaneya, Yusuke*; Nagame, Yuichiro; Sch
del, M.
no journal, ,
We have successfully developed an on-line isothermal gas chromatographic apparatus for the study of gas chemistry of the transactinide elements dubnium (Db, Z = 105). Isothermal gas chromatographic behavior of oxychlorides of Nb and Ta, as the lighter homologues of Db, were observed, and the adsorption enthalpies of the Nb and Ta compounds on a quartz surface were determined. Db was also chemical separated in the similar condition.
Endo, Hitoshi
no journal, ,
Polyrataxane (PR) is one of supermolecular assemblies in which a linear polymer penetrates a few hundreds ring molecules. The typical PR is synthesized by using polyethylene glycol (PEG) as the axial polymers and 
-cyclodextrin (CD) as the ring molecules. We investigated the structure and dynamics of PR by means of contrast variation neutron scattering experiments, in which the contrast variation small-angle neutron scattering experiments were performed for the investigation of the structure of PR and the contrast variation neutron spin echo experiments were applied to elucidation of the dynamics of PR. In order to study the properties of CD threaded into PEG, partially deuterated CD and PEG were synthesized for the preparation of PR with protonated CD and deuterated PEG (CD visible) and PR with deuterated CD and protonated PEG (PEG visible). The contrast variation neutron scattering experiments were performed with these two materials and additional fully protonated PR, then the observed scattering profiles could be decomposed into the partial scattering functions of each component, which leads to detailed analyses of the structure and dynamics of CD and PEG in PR separately with nanoscopic temporal-spatial resolution.