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Lu for radioimmunotherapyWatanabe, Satoshi; Hashimoto, Kazuyuki; Watanabe, Shigeki; Iida, Yasuhiko*; Hanaoka, Hirofumi*; Endo, Keigo*; Ishioka, Noriko
no journal, ,
Br-MBBGWatanabe, Shigeki; Hanaoka, Hirofumi*; Liang, J. X.; Watanabe, Satoshi; Iida, Yasuhiko*; Endo, Keigo*; Ishioka, Noriko
no journal, ,
Esaka, Fumitaka; Magara, Masaaki; Suzuki, Daisuke; Miyamoto, Yutaka; Lee, C. G.; Kimura, Takaumi
no journal, ,
In this study, inductively coupled plasma - mass spectrometry (ICP-MS) is applied to the analysis of plutonium isotope ratios in individual particles. Prior to the measurement, individual plutonium particles in samples are identified by using scanning electron microscope (SEM) and are transferred to each Si chip by a micro-manipulator attached to the SEM system. After removed from the SEM chamber, each particle is dissolved with HF-HNO
solution for subsequent ICP-MS analysis. As a result, the 
Pu/
Pu plutonium isotope ratios in individual particles with the diameter of around 1 micro-meter are successfully determined with good precision. A remaining subject to be solved is the mass interferences by co-existing elements such as americium. In order to remove the interferences, we are developing methods for chemical separation of americium and plutonium, based on anion exchange and capillary electrophoresis systems.
Itakura, Ryuji; Hasegawa, Hirokazu*; Kurosaki, Yuzuru; Yokoyama, Atsushi; Oshima, Yasuhiro*
no journal, ,
When neutral molecules are partly ionized in intense laser fields (I
35 TW/cm
), a hole in the rotational wave packet of the remaining neutral NO is formed by the ionization, whose rate depends on the alignment angle of the molecular axis with respect to the laser polarization direction. Rotational state distributions of NO are experimentally observed with the spectroscopic technique and then the characteristic feature that the population at higher J levels is increased by the ionization can be identified. Numerical calculation for solving time-dependent rotational Schr
dinger equations including the effect of the ionization is carried out. The numerical results suggest that NO molecules aligned perpendicular to the laser polarization direction are dominantly ionized at the peak intensity of I = 42 TW/cm, where the multiphoton ionization is preferred rather than the tunneling ionization.
Oka, Kiyoshi; Seki, Takeshi*; Komori, Yuki
no journal, ,
We developed a new minimally invasive laser device system using a composite-type optical fiberscope. The fiberscope consists of a centrally located 
0.1 mm single fiber for laser treatment and its surrounding about 9,000 (5 
m/piece) fibers for diagnosis. This system enables transmission of an image and 50 W Yb: fiber laser in parallel. By applying our fiberscope to laser treatment in various medical fields, it enables acquisition of an image, laser treatment, blood flow measurement, estimate of distance only in one fiberscope. By using this device for the PDT treatments applied to such as lung and cervical cancers, we expect to spot the irradiated area selectively while looking at a lesion. In this paper, we present a composition of minimally invasive laser therapy device using 1 mm composite-type optical fiberscope, the basics performance experiment result and an application to PDT therapy.
Idesaki, Akira; Seguchi, Tadao*; Tamura, Kiyotoshi; Oshima, Takeshi; Shimada, Akihiko; Kudo, Hisaaki*
no journal, ,
The degradation of polyvinylchloride (PVC) of cable insulation was investigated by accelerated radiation and thermal ageing. The sheets of PVC as same formulation as cables were subjected to thermal ageing at temperature range 100-135
C and/or to radiation ageing by Co-60 
-rays at a dose rate of 1kGy/h in air. The degradation was evaluated by the tensile test and by the weight change. The relations between elongation at break and change of weight by loss of plasticizer were analyzed. At higher temperature, the plasticizer evaporates to cause the decay of tensile properties.
Shimada, Akihiko; Seguchi, Tadao*; Tamura, Kiyotoshi; Oshima, Takeshi; Idesaki, Akira; Kudo, Hisaaki*
no journal, ,
Silicone rubber (SiR) sheets with different formulation were examined on the two points, specimen's thickness and thermal and radiation combined accelerated ageing. The 0.5 and 2 mm thick sheets were aged by thermal at up to 235C and Co-60 rays radiation with 1 kGy/h up to 800 kGy. The degradation was measured by tensile testing and gel fraction and swelling experiments. For check the distribution of degradation in depth of sheet, the 2 mm sheet sample was sliced by 0.3 mm thickness after ageing. The results indicated that the degradation progressed uniformly throughout the 2 mm thick sheet. For the ageing combination, the degradation by three different combinations was examined, that is, (a) simultaneous ageing, (b) thermal and radiation sequential ageing, and (c) radiation and thermal reversed sequential ageing. Elongation at break indicated that the order of degradation mild to severe was reverse sequential, sequential, simultaneous ageing.
Akagi, Hiroshi; Itakura, Ryuji; Hosaka, Koichi*; Otobe, Tomohito; Yamanouchi, Kaoru; Yokoyama, Atsushi
no journal, ,
When a molecule is exposed to circularly-polarized laser fields, dissociation processes following ionization proceed differently from the case of linearly polarization. In the present work, ethanol molecules are irradiated with a circularly-polarized intense laser field (I = 1.4
10
W/cm, 
800 nm), and the produced electron and ion are measured in coincidence. The relative yields of C
H
OH
, CHOH, and CH
C with respect to the parent ion are 0.36, 0.31, and 0.01, which correspond to only 0.5, 0.4, and 0.2 of those for the linear polarization with similar laser field intensity (1.710 W/cm), showing that the polarization change from linear to circular significantly suppresses the C-H, C-C, and C-O dissociation processes.
Sato, Nozomi; Asai, Masato; Tsukada, Kazuaki; Sato, Tetsuya; Toyoshima, Atsushi; Li, Z.; Nagame, Yuichiro; Sch
del, M.; Ichikawa, Shinichi
no journal, ,
First ionization potentials (IPs) of heavy elements with atomic numbers Z 100 have not been determined up to now. Recently we have been developing a surface ionization type ion source to measure the IP of the heaviest actinide, lawrencium (Lr, Z = 103). The surface ionization comparison technique is a promising approach to measure the IP of Lr on an atom-at-a-time scale. We will present the status of our development for an apparatus for this measurement.
Toyoshima, Atsushi; Tsukada, Kazuaki; Asai, Masato; Kitatsuji, Yoshihiro; Ishii, Yasuo; Sato, Tetsuya; Li, Z.; Sato, Nozomi; Kikuchi, Takahiro; Nishinaka, Ichiro; et al.
no journal, ,
Electrochemical studies of nobelium (No) and mendelevium (Md) using an electrolytic column chromatography at JAEA will be presented. The isotopes 
No and Md were produced in the 
Cm(
C, 5n) and Cm(
B, 4n) reactions, respectively, at the JAEA tandem accelerator. In the experiment of No, the oxidation of No
to No
in 0.1 M 
-hydroxyisobutyric acid (-HIB) was studied with comparing with the elution of Sr and Yb. At the applied potential of 0.2 V, No was not eluted with -HIB. This adsorption of No was the same as that of Sr, indicating that No was bound in its stable divalent state. On the other hand, the elution of No in -HIB was observed at 1.2 V at the position of Yb, which demonstrated that No was successfully oxidized to No. Reduction of Md to Md was also successfully carried out with the apparatus in 0.1 M HCl.
mixed solution using an on-line chemical apparatusTsukada, Kazuaki; Kasamatsu, Yoshitaka*; Asai, Masato; Toyoshima, Atsushi; Ishii, Yasuo; Li, Z.; Kikuchi, Takahiro; Sato, Tetsuya; Nagame, Yuichiro; Schdel, M.; et al.
no journal, ,
We have investigated the chemical behavior of Db together with its group-5 homologues by anion-exchange chromatography in HF/HNO mixed solution using a rapid online chemical apparatus (AIDA-II). The nuclides 
Db, 
Nb and 
Ta were produced in the Cm(
F, 
n), 
Ge(F, 
n) and Gd(F, n) reactions, respectively, at the JAEA tandem accelerator. On-line anion-exchange separations of Db, Nb and Ta were performed using the AIDA-II. Thousand times of anion-exchange separations were conducted using AIDA-II. events were registered, and the 
values for Db was evaluated. From these results, the adsorption sequence Pa 
Db Nb 
Ta was determined. The present result shows a notable difference in the adsorption behavior between Db and its homologue Ta. In the conference, the present status and the perspective of the aqueous chemistry of Db at JAEA will be also presented.
Tsukada, Kazuaki; Kasamatsu, Yoshitaka*; Asai, Masato; Toyoshima, Atsushi; Ishii, Yasuo; Tome, Hayato*; Nagame, Yuichiro
no journal, ,
Aqueous chemistry of element 105, dubnium (Db), is now being performed at JAEA. The nuclide 34-s Db is produced in the Cm(F, 5n) reaction with the production rate of about 0.25 atoms per min. To obtain more accurate data with high statistics, we have developed a new device, AIDA-II (Automated Ion-exchange separation apparatus coupled with the Detection system for Alpha-spectroscopy), based on a continuous sample preparation and detection system, i.e., continuous collection and evaporation of effluent, and successive -particles measurement. The sample preparation is accomplished within 20 s, and AIDA-II enables us to perform cyclic discontinuous column chromatographic separations of short-lived nuclides in aqueous solutions and automated detection of -particles within a typical cycle of about 80 s. In the conference, we will present the new device and a result of -particle detection in the Db experiment.
Tamada, Masao; Kasai, Noboru; Seko, Noriaki; Shimizu, Takao*
no journal, ,
The uranium dissolved in seawater is extremely low concentration of 3.3 ppb. However, the total amount of uranium resource in seawater is 4.5 billons tons which is one thousand times of that in terrestrial ores. For uranium collection from seawater, amidoxime group was selected as a high affinity group in adsorbent. This adsorbent was synthesized by grafting of acrylonitrile and subsequent chemical treatment with hydroxylamine. The collection of uranium from seawater was performed in marine experiments at Aomori and Okinawa, Japan. In Aomori, 350 kg of the fibrous adsorbent stacks were dipped at 7 km offing of Aomori seashore. In total 9 tests over three years, 1 kg of uranium could be collected successfully as a yellow cake. A new braid type adsorbent has been developed to achieve the practical cost of uranium collection. The adsorption performance in Okinawa marine experiment indicated 1.5 g-U/kg-ad for 30 day soaking. The promising collection cost reached 25 thousand yen/kg-U which is equivalent to 
96/lb-UO
.
Tsukui, Narutaka; Yamada, Keiichi*; Watanabe, Shigeki; Hanaoka, Hirofumi*; Oku, Hiroyuki*; Endo, Keigo*; Ishioka, Noriko; Matsuo, Ichiro*
no journal, ,
Saito, Hiroyuki; Machida, Akihiko; Katayama, Yoshinori; Aoki, Katsutoshi
no journal, ,
113 produced by the 
Bi(
Zn,n)113 reactionMorimoto, Koji*; Morita, Kosuke*; Kaji, Daiya*; Haba, Hiromitsu*; Ozeki, Kazutaka*; Kudo, Yuki*; Sato, Nozomi; Sumita, Takayuki*; Yoneda, Akira*; Ichikawa, Takatoshi*; et al.
no journal, ,
We performed the experiment to synthesize an isotope of the element 113 produced by a Bi(Zn,n)113 reaction using a gas-filled recoil ion separator (GARIS) at RIKEN. Two decay chains were observed, and assigned to those originating from an isotope 113. Both chains were connected into the previously known decays of 
Bh and Db via previously unknown decays of 113, 
Rg, and 
Mt. Although the Bh was known nuclide, a number of atoms reported so far was limited. In order to study more precise decay property of the Bh, we performed the direct production of Bh by the Cm(
Na,5n)Bh reaction. In this experiment, the Bh was clearly identified from the correlation of the nuclide, Db. The obtained decay properties of Bh and Db are consistent with those observed in the 113 chain, which provided further confirmation of the discovery of 113.
Kaji, Daiya*; Morimoto, Koji*; Sato, Nozomi; Yoneda, Akira*; Haba, Hiromitsu*; Ozeki, Kazutaka*; Sumita, Takayuki*; Morita, Kosuke*
no journal, ,
We designed a new gas-filled recoil ion separator GARIS-II for actinide-based asymmetric fusion (hot fusion) study at RIKEN. GARIS-II was designed on the basis of extensive experiences with construction, development, and operation of GARIS. GARIS-II consists of five magnets arranged in a Qv-D-Qh-Qv-D configuration, where D and Q denote dipole and quadrupole magnets, respectively. Ion optical characteristics were analyzed using the computer code TRANSPORT. The solid angle of GARIS-II is 20.2 msr. The total path length of the separator is 5.12 m. GARIS-II will be able to use various filled gas, such as He and He/H2 mixture. The separator will be able to transport the recoil ion with magnetic rigidity of 2.44 Tm.
Seguchi, Tadao*; Tamura, Kiyotoshi; Shimada, Akihiko; Idesaki, Akira; Oshima, Takeshi; Kudo, Hisaaki*
no journal, ,
The degradation mechanisms of polymer materials as PE, EPR for cable insulations in a nuclear power plant were studied by accelerated thermal and radiation ageing. The contribution of stabilizers to polymer degradation was investigated by the measurements of oxidation products, content of stabilizers, and also mechanical properties. It was found that an antioxidant among the stabilizers was very effective to decrease the thermal oxidation but less effective to the radiation induced oxidation. The content of the antioxidant decreases by evaporation during thermal ageing and by decomposition with dose during radiation ageing. The new degradation mechanisms in polymer ageing are proposed.
Shimojo, Kojiro; Mitamura, Hisayoshi; Naganawa, Hirochika
no journal, ,
no abstracts in English
Onuki, Toshihiko
no journal, ,
Mineralization of actinides and rare-earth elements on the interface between solution and surface of microorganisms and minerals has been studied in the field of uranium ore deposit and by the experiments. These mineralization is very important for the confinement of long-lived radionuclides in geosphere.