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isotopologues using femtosecond laser-induced molecular alignmentAkagi, Hiroshi; Kasajima, Tatsuya*; Kumada, Takayuki; Itakura, Ryuji; Yokoyama, Atsushi; Hasegawa, Hirokazu*; Oshima, Yasuhiro*
no journal, ,
We propose a laser isotope separation method without tunable lasers, and demonstrate isotope selective ionization of nitrogen isotopologues. This method is based on molecular alignment and angular dependent ionization. A non-resonant femtosecond (fs) laser pulse with a linear polarization creates rotational wave packets in the isotopologues. These wave packets periodically exhibit aligned and antialigned distributions at specific time delays. At a specific time delay when one isotopologue is aligned and the other one is anti-aligned, another non-resonant linearly-polarized fs laser pulse (ionization pulse) ionizes the aligned isotopologue preferentially via the non-resonant multiphoton ionization, because of angular dependence of the N ionization probability. The ion yield ratio R [= I(
N) / I(
N)] depends on the time delay, ranging from 0.68 to 1.41.
Tsukada, Kazuaki; Sato, Nozomi*; Watanabe, Satoshi; Ishioka, Noriko; Hatsukawa, Yuichi; Hashimoto, Kazuyuki; Kin, Tadahiro*; Takeda, Shinsaku*; Kawabata, Masako; Saeki, Hideya; et al.
no journal, ,
A new system has been proposed for the generation of radioisotopes with accelerator neutrons by deuterons, especially the production of Mo-99, Y-90, Cu-67, and Cu-64. Enriched Mo-100, Zr-90, Zn-68 and Zn-64 oxide samples were irradiated with neutrons, which were obtained by the 
C(d,n) and Be(d,n) using 40 MeV deuterons provided from the TIARA cyclotron. Mo-99, Y-90, Cu-67, and Cu-64 were successfully produced via the (n, x) reactions, and we clearly observed the 
-rays. Particularly, yields of impurity radionuclides were much smaller than that of Mo-99 and Cu-67, and therefore radioactive waste produced during chemical processing would be reduced compared with other proposed reaction systems. The present results demonstrate that the radioisotopes, Mo-99, Y-90, Cu-67, and Cu-64, can be produced by using fast neutrons, and strongly suggest that the reaction system is one of the most promising routes to produce high quality medical radioisotope.
Hoshina, Hiroyuki; Seko, Noriaki; Ikegawa, Atsushi*; Hatanaka, Hiroshi*
no journal, ,
Nagaishi, Ryuji; Inoue, Masao; Matsumura, Taichi; Yamagishi, Isao; Hino, Ryutaro; Ogawa, Toru
no journal, ,
Hydrogen gas generation in radiolysis of pure water or seawater coexisting with zeolite adsorbents has been investigated by using Co-60 -ray for hydrogen safety in decontamination of radioactive water after Fukushima Daiichi NPS accident. In this work, two types of void volumes present in the zeolite bed were paid attention microscopically, and the difference in water radiolysis between the volumes was considered. The oxygen generated by decomposition of hydrogen peroxide, as the counterpart of hydrogen molecule, contacting with the zeolites were also discussed.
SO
with Aliquat336 as homologues of seaborgium (Sg)Mitsukai, Akina; Toyoshima, Atsushi; Asai, Masato; Tsukada, Kazuaki; Sato, Tetsuya; Kaneya, Yusuke; Takeda, Shinsaku*; Nagame, Yuichiro; Komori, Yukiko*; Murakami, Masashi*; et al.
no journal, ,
We have started studying sulphate-complex formation of a transactinide element, seaborgium (Sg). In this study, we report on the extraction behavior of carrier-free radioisotopes 
Mo and 
W which are lighter homologs of Sg, from aqueous HSO solution with amine extractant, Aliquat336, dissolved in toluene by a batch method. These radioisotopes were produced in the Zr(
,
)Mo and Ta(
,x
)W reactions at the RIKEN K70 AVF cyclotron. Results of the extraction experiments showed that the distribution ratios of Mo and W increase sharply above ~3.0 M HSO. Based on the slope analysis, it was indicated that anionic sulphate-complex of [MO(SO)]
(M = Mo, W) are formed in 
5 M HSO. These results suggest that the present system is applicable to the extraction of Sg.
Onuki, Toshihiko; Sakamoto, Fuminori; Kozai, Naofumi; Yamasaki, Shinya*; Yu, Q.
no journal, ,
We have examined the accumulation of radioactive Cs by mycelia of filamentous fungi by combining agar medium method with autoradiography (AR) analysis using imaging plate. Radioactive Cs was accumulated in the mycelia of 1500 species of the filamentous fungi between ca. 10 and ca. 1000 times higher than in medium. The presence of minerals in the agar medium reduced the accumulation of radioactive Cs in the mycelia. One of the reasons for the resistance is probably adsorption of radioactive Cs by minerals in the soil. The irreversible accumulation in cells caused excess radioactive Cs in the hyphae than that expected by Kd model.
Miyahara, Kaname; Iijima, Kazuki
no journal, ,
This presentation provides a concise overview of knowledge and experience gained from the activities for environmental remediation after the Fukushima Dai-ichi accident to establish the technical basis for strategic, off-site response to nuclear incidents. It is produced by JAEA, reflecting JAEA's key role in the research associated with both remediation of contaminated areas and the natural processes influencing contamination migration in non-remediated areas. This presentation also provides a perspective on the future actions to facilitate return of residents to the most contaminated zones from the standpoint of environmental chemistry and radiochemistry with special emphasis on associated waste management.
Iwata, Hajime; Kitamura, Akira
no journal, ,
The solubility of Nb was measured using oversaturation and undersaturation method. Compared with the values evaluated using JAEA-TDB, in the OS method a similar solubility was observed, and the measured values in the US method were around three orders magnitude below the evaluated values. It suggests that the solubility limiting solid differ between OS and US method.
Baba, Yuji; Shimoyama, Iwao; Hirao, Norie; Izumi, Toshinori
no journal, ,
In order to clarify the chemical states of radioactive cesium in clay minerals, the X-ray photoelectron spectra (XPS) have been measured for cesium and the other alkali metals on oxides and micaceous oxides. Since the number of atoms in radioactive Cs-137 is extremely small, we focused on the adsorption of trace amount of cesium. For this purpose, we applied total reflection XPS (TR-XPS) using synchrotron radiation. For micaceous oxide, the TR-XPS spectra show that the cesium is more positively charged compared with that for thicker layer. It was shown that trace-level cesium in micaceous oxides is ionically bonded at the interlayer due to the negative charge of the micaceous oxide. We consider that the observed unique adsorption-desorption behavior is specific to only trace-level cesium.
Meguro, Yoshihiro; Sato, Junya; Kato, Jun; Nakagawa, Akinori; Koma, Yoshikazu; Ashida, Takashi
no journal, ,
A large quantity of contaminated water is accumulated in nuclear reactor buildings in Fukushima Daiichi Nuclear Power Station. Because various radionuclides are dissolved in the accumulated water, several decontamination devices based on deposition and adsorption are used for the decontamination. Therefore, several sludge and used adsorption materials are generated. These most are different from wastes caused by the operation of commercial nuclear power stations so far in properties, and these have not been disposed of commercially. As then feasibility of conventional solidification techniques to the wastes should be investigated prior to selection of solidification technique of the wastes. In this study as a first step of feasibility study, three types of sludge and three absorbents were solidified using cement materials and solidification behavior and properties of solidified material were investigated, and then feasibility of cementation to these wastes was evaluated.
Idesaki, Akira; Sugimoto, Masaki; Shimada, Akihiko; Yamamoto, Shunya; Taguchi, Mitsumasa; Yamaki, Tetsuya
no journal, ,
Recently, development of platinum-substitute catalysts has been studied extensively; it has been found that a nitrogen-containing carbon material shows oxygen reduction activity almost same as platinum metal. We have been studying about synthesis process of a nitrogen-containing carbon material by pyrolysis of polymer precursors which are easy to be shaped as fiber, film, and so on. In this work, some materials were selected as polymer precursors and their organic-inorganic conversion process were investigated. It was found that polyimide and phenol resin show high carbon yield of 50-60% and graphite structure is formed above 800
C.
Seko, Noriaki; Amada, Haruyo; Hoshina, Hiroyuki; Ikegawa, Atsushi*; Hatanaka, Hiroshi*
no journal, ,
Motokawa, Ryuhei; Kobayashi, Toru; Endo, Hitoshi*; Suzuki, Shinichi; Yaita, Tsuyoshi; Shiwaku, Hideaki
no journal, ,
Okumura, Masahiko; Nakamura, Hiroki; Machida, Masahiko; Sassi, M.*; Rosso, K.*
no journal, ,
no abstracts in English
Sekine, Yurina; Ishikawa, Nozomi*; Fukazawa, Tomoko*
no journal, ,
no abstracts in English
Goto, Mitsuaki*; Yamaki, Tetsuya; Koshikawa, Hiroshi; Sawada, Shinichi; Kitamura, Akane; Higa, Mitsuru*
no journal, ,
We have exploited a grafting technique with heavy-ion beams to create ion exchange membranes for various practical applications such as fuel cells and water desalination systems. In this study, instead of styrene that is a common monomer, sodium styrene sulfonate (SSS) was for the first time employed for this so-called ion-track grafting. A 25 
m-thick poly(vinylidene fluoride) film was bombarded with 560 MeV 
Xe at a fluence of 3.0
10
or 1.010
ions/cm
, and subsequently immersed in a SSS grafting solution at 60C. The charge density was estimated through the measurement of the membrane potential in an aqueous solution of potassium chloride. Our membranes exhibited higher charge density than the conventional or commercially-available samples probably due to track structures characteristic of the bombarding heavy ions.
Tanaka, Kazuya; Fan, Q.*; Sakaguchi, Aya*; Takahashi, Yoshio*
no journal, ,
Most of FDNPP-derived radiocesium in the aerosols was water-soluble. However, little amount of radiocesium in soils was leached with water. Such soluble fraction of radiocesium was strongly fixed on soil particles after deposition on the ground. This strong fixation of radiocesium can be explained by formation of inner-sphere complex in clay minerals, which was confirmed by EXAFS analysis. Many spots showing strong radioactivity were also found on the surface of soil. This indicates that the fallout radiocesium was heterogeneously distributed on the ground in a micro-scale. Most of radiocesium in river suspended particles was particulate form, and micro-scale distribution was not homogeneous, reflecting the heterogeneity of radiocesium in soil. Dissolution of radiocesium in the aerosols and subsequent strong adsorption onto soil particles are responsible for the preservation of the heterogeneous distribution of radiocesium in the environment.
Suzuki, Shinichi; Kobayashi, Toru; Shiwaku, Hideaki; Yaita, Tsuyoshi
no journal, ,
and lanthanide series elementsKamezawa, Akinori*; Suzuki, Shinichi; Kobayashi, Toru; Sueki, Keisuke*
no journal, ,
At]astato--methyl-L-phenylalanine (2-AAMP) as a novel radiopharmaceutical for internal radiotherapyOhshima, Yasuhiro; Suzuki, Hiroyuki*; Hanaoka, Hirofumi*; Watanabe, Shigeki; Watanabe, Satoshi; Watanabe, Naoyuki*; Tsushima, Yoshito*; Endo, Keigo*; Arano, Yasushi*; Ishioka, Noriko
no journal, ,