English abstracts

2S01 Establishment and the present status ofanimal archives in and around the exevacuation zone of the Fukushima Daiichi
Nuclear Power Plant (FNPP) accident
FUKUMOTO, M.1, THE GROUP FOR
COMPREHENSIVE DOSE EVALUATION IN
ANIMALS FROM THE FNPP AFFECTED
AREA2(1, 2Tohoku Univ.)
The Fukushima Daiichi Nuclear Power
Plant (FNPP) accident released large amounts ofradioactive substances into the environment.
Since the FNPP accident, major concern in theworld has been the health effect of long-term low
dose exposure to both internal and externalradiations. However, it is impossible to perform
such exposure experiments including laboratory
animals. The very important characteristics of the
FNPP accident is that the accident happened inJapan which is one of the most advanced andopen countries and the amount of released
radionuclides was 1/10 of the Chernobyl accident.
We collected organ specimens from cattle, pigs
and wild Japanese monkeys within and adjacentto the 20-km radius previously set as theevacuation zone of FNPP. We have been
performing
determinationof
organ
concentrations of radionuclides and their
biological effects. I will address how we haveestablished the archive system, what we knew
using our archive system, and problems we arefacing at.

1A01 Differences by the source reactor of theradioactive particles emitted from the
Fukushima Dai-ichi Nuclear Power Plant
accident
SATOU, Y.1, ADACHI, K.2, ONO, T.1, IIZAWA,
Y.2, ABE, Y.1, NAKAI, I.2, IGARASHI, Y.1,
SASA, K.2, SUEKI, K.2,
(1University of Tsukuba, 2MeteorologicalResearch Institute, 3Tokyo University of Science)149

The radioactive particles have been emitted
to environment in the Fukushima Daiichi Nuclear
Power Plant accident in 2011. At least theseparticles were emitted from the units 1 and 2.
However, the details have not been clarified yet.
This study performed isolation of radioactive
particles including so-called Cs bearing particles,
from
soil
samples,
andperformed
characterization. And we disclosed differences
between the particles from the units 1 and 2. We
isolated each four radioactive particles from twosoil samples. The radionuclides 134Cs and 137Cs
were detected by gamma spectroscopy in all of
the particles. However, no other gamma emitterswere detected in the particles. The specificradioactivity of particles from unit 1 is lower thanthat from unit 2. A significant amount of Ba has
been detected in the particles from unit 1.
However, distribution of Ba were different fromthat of Cs. For this reason, origin of Ba could not
be a decay product of Cs. In addition, a
distribution of Fe and Zn were not consistent withthat of Cs. In contrast, Si and Ca were detected incommon. Si is one of major components in theradioactive particles emitted by the Fukushima
accident.

1A02 Development of rapid separation
method of plutonium and americium
contained in the soil sample
SUZUKI, K., UESUGI, M., YAMAMORI,
K.,YOKOYAMA,A.,(Gread. School Nat. Sci. Tech., Kanazawa Univ.)
Artificial elements of Pu and Am generated
in nuclear fuel are known to be released from
Fukushima Nuclear Power Plant in March, 2011.
In this study, we aim to develop a rapid
quantitative analysis of Pu and Am in the soil
sample for nuclear emergency. We focused firstly
on dissolution and pre-concentration, andsecondly, on speeding up purification for Am in
the sequential analysis. The ammonium nitratefusion and the purification of Am by a DGA resin
column have been examined. In the procedure,
DDTC solvent extraction was found necessary toeliminate polonium atoms. Finally, we ensured
that these procedures were applicable to the soil
samples for monitoring contamination in
Fukushima.

1A04 Dynamism of radioactive cesium inblood and muscle of cattle fed with radioactive
contaminated silage
SUZUKI, M.1, SUZUKI, H.2, ISHIGURO, H.2,
KINO, Y.2, URUSHIHARA, Y.1, WATANABE,
S.2, SAITO, Y.2, KOZUTSUMI, T.2, SOCHI, Y.4,
NISHI, K.4, ABIKO, R.1, WASHIO, R.1,
KUWAHARA, Y.1, NUMABE, T.2, SEKINE, T.5,
FUKUMOTO, M.1(1IDAC, Tohoku Univ., 2Miyagi Prefect. Livest.
Expt. Stn., 3Dept. Chem., Tohoku Univ., 4Sendai
Livest. Hyg. Ctr., 5IEHE, Tohoku Univ.)
We investigated the correlation of internal
radiocesium deposition determined by blood
monitoring and by surface monitoring on the neckor ramp muscle of live-cattle using a NaI
surveymeter. Blood and muscle radiocesium
concentration was measured in a Ge spectrometer.
Seven-month-old or matured Japanese black
cattle were fed with radiocesium-contaminatedsilage for approximately 60 days, thereafter, withcontamination free clean silage.
Surface monitoring values (cps) were wellcorrelated with radiocesium concentration(Bq/kg) in the dissected muscle. Therefore, we
could convert the surface monitoring value toradiocesium concentration in the muscle. We
further compared surface monitoring data withblood monitoring data. Radiocesium appeared toaccumulate in muscle and blood with similar
kinetics over the period of feeding with thecontaminated silage. On the other hand, thedecrease in the muscle was slower than that inblood after switching to the clean silage. It was
confirmed that biological halflife (Tb) wasapproximately 2 weeks and 1 month in blood andthe muscle, respectively. We also found the agedependent elongation of Tb in the muscle.
The present study revealed that internal
radiocesium deposition can be estimated bysurface monitoring, as the noninvasive method.

1A03 A Cesium detachment from the clay
minerals using molten salt treatment andstructure analysis
HONDA, M. 1, SHIMOYAMA, I. 1, KOGURE, T.
2, OKAMOTO, Y. 1, SUZUKI, S. 1, YAITA, T. 1
(1JAEA, 2Tokyo Univ.)
There is the issue of soil contamination
problem with the radioactive cesium (Cs) large
quantities scattering with the Fukushima first
Nuclear Power Plant accident without the stillradical solution that nearly four years passed
being done by outbreak. The molten salt
treatment method is one of the effective Cs
removals, however, waste increases in thing anddetachment needing a high temperatureprocessing process and still has a problem forpractical use. In this study, we investigated the Cs
detachment by the low pressure sublimation
method using the molten salt (NaCl, CaCl2 mixedsalt) and the structure analysis at the Cs removalfrom clay minerals and a reuse materials search.
When we gave low-pressure processing with
NaCl, CaCl2 mixed salt and heated, we achieved
Cs removal rate 100% at 700 degrees. As a resultof structure analysis of the clay minerals which
occurred in a heating process using X-rays
diffraction method (XRD) and transmission
electron microscope (TEM-EDS), Cs formed theplural structure called the Calcite, Hematite,
Augite, and Wadalight and knew that Cs wasremoved while the frame structure of clay
minerals changed.

150

We will discuss conditions to be considered for
calculating surface monitoring values to muscle
radiocesium concentrations.

1A05 Strontium-90 in fishes after the
Fukushima Dai-ichi Nuclear Power Plant
accident
MIKI, S.1, FUJIMOTO, K. 1, MORITA, T. 1,
SHIGENOBU, Y. 1, TAKAGI, K. 1, ONO, T. 1,
WATANABE, T. 2, SUGISAKI, H. 1
(1Ntl. Res. Inst. of Fish. Sci, 2Tohoku Ntl. Fish.
Res. Inst.)
Radioactive wastewater released from the
Fukushima Dai-ichi Nuclear Power Plant(FDNPP) includes the high concentration of 90Sr.
After the wastewater was discharged into the sea,90
Sr in seawater were only temporarily detected
near the FDNPP harbor. Strontium-90 in seawater
was spread across the ocean and diluted toundetectable level. Even though 90Sr in marine
fishes are not detected, citizens raised questions
about the safety of the fishes because of releasing
the high concentrations of 90Sr from the FDNPP.
Therefore, in this study, we investigated theconcentrations of 90Sr in marine fishes collectedfrom the coast of east Japan. The concentration of90
Sr in various fishes caught around the coast ofeast Japan was the same as that before theaccident. Although the concentration of 90Sr in
Sebastes cheni caught near the FDNPP in Dec.
2011 was 1.2 Bq/kg w.w. that of in S. cheni caught
off Fukushima prefecture in Jun 2012 wasundetectable. Therefore we suggest that thecontamination of 90Sr in marine fishes may belocalized to a small region near the FDNPP harbor.
All the results showed the concentration of 90Sr inmarine fishes was notably lower than that of 137Cs.

1A06 Development for fish bone ash certified
reference material for 90Sr analysis (1)151preparation of candidate material andevaluation of homogeneity
MIURA, T.,1 MINAI, Y.,2 HIRAI, S.3,
IWAMOTO, H.4, YONEZAWA, C.5, KAKITA,
K.6, KOJIMA, I.6, OKADA, A.7, OKADA, Y.8,
SANADA,
T.9,
SHIBUKAWA,
M.10,
TAKAGAI, Y.11, ARAKAWA, F.12, MAEYAMA,
K.13, YAMADA, T.14, OTA, H.15, FURUKAWA,
M.16, UEMATSU, Y.17
(1NMIJ/AIST, 2Musashi Univ., 3Tokyo City Univ.,
4
Enivironmental Technology Service, 5CPDNP,
6
JSAC, 7Toshiba Environmental Solution, 8Tokyo
City Univ. Atomic Energy Research Lab.,
9
Hokkaido Univ. of Sci., 10Saitama Univ.,
11
Fukushima Univ., 12NH Foods R&D center,
13
JCAC, 14JRIA, 15KANSO, 16PerkinElmer,
17
JAB)
Following the mega earthquake, tsunami,
and the accident at the Fukushima Daiichi nuclear
power plant on 3.11.2011, a massive amount ofradioactive nuclides were released into theenvironment in Japan. The emergency situation
required urgent measurements of radioactive
isotopes in environmental samples and foodsamples for human health. It was required that thecertified reference material of food sample forvalidation of measurement of radioactive
isotopes because the certified reference material
is essential for accurate and precise measurementof radioactive isotopes in these samples. We havedeveloped and supplied the certified referencematerial of food and environmental samples. The
developed certified reference materials are brownrice grain, beef flake, soybean powder, shiitake
mushroom powder, in which certified massic
activities (Bq kg-1) of 134Cs, 137Cs and 40K. In thispaper, we described the development of certified
reference material of fish bone ash (90Sr, 134Cs,
137
Cs and 40K). These new certified referencematerials are useful for validation of Jray
spectrometry of 134Cs, 137Cs and radiochemical
analysis of 90Sr in fish sample.

1A07 Development for fish bone ash certified
reference material for 90Sr analysis (2) the
results of inter-laboratory experiments
MIURA, T.,1 MINAI, Y.,2 HIRAI, S.3,
IWAMOTO, H.4, YONEZAWA, C.5, KAKITA,
K.6, KOJIMA, I.6, OKADA, A.7, OKADA, Y.8,
SANADA,
T.9,
SHIBUKAWA,
M.10,
TAKAGAI, Y.11, ARAKAWA, F.12, MAEYAMA,
K.13, YAMADA, T.14, OTA, H.15, FURUKAWA,
M.16, UEMATSU, Y.17
(1NMIJ/AIST, 2Musashi Univ., 3Tokyo City Univ.,
4
Enivironmental Technology Service, 5CPDNP,
6
JSAC, 7Toshiba Environmental Solution, 8Tokyo
City Univ. Atomic Energy Research Lab.,
9
Hokkaido Univ. of Sci., 10Saitama Univ.,
11
Fukushima Univ., 12NH Foods R&D center,
13
JCAC, 14JRIA, 15KANSO, 16PerkinElmer,
17
JAB)
In this presentation, we will present theresults of inter-laboratory experiments forcertification of massic activities of 90Sr in thecandidate material for fish bone ash certified
reference material. The 14 laboratories in Japanand 7 overseas laboratories participated on theinter-laboratory experiments. The analyticalresults of 90Sr in the candidate material by
Japanese laboratories were consistent with eachother. The certified value of 90Sr in the fish boneash certified reference material was determinedby the analytical results of Japanese laboratories.
The analytical results of 90Sr by overseas
laboratories were in good agreement with thecertified value.

1A08 Investigation of selective extraction of Cs,
Sr by using solvent extraction II
SHIRASAKI, K., NAGAI, M., SAKAMOTO, K.,
YAMAMURA, T.
(Institute for Materials Research, Tohoku
University)
Previously, we discussed the ability of152

selective extraction of Sr(II) ion from aqueous
solution by using crown ether and Perfluoro-1,11trioxaundecane-2,10-dioic acid (PFTOUDA) as
co-extractant, and HFC as diluent. In the present
work, 9 compounds, 2,2,3,3,4,4,5,5-Octafluoro1,6-hexyldiacrylate (No. 1), 2,2,3,3,4,4,5,5Octafluoro-1,6-hexyldimethacrylate (No. 2),
Dimehyldodecafluorosuberate(No.
3),
Dimehylhexa decafluorosebacate (No. 4),
Perfluoro-3,6,9-trioxadecanoic acid (No. 5),
Dimethylperfluoro-1,10-decanedicarboxylate(No. 6), Perfluoro-1,10-decanedicarboxylic acid(No. 7), Dodecafluorosuberic acid (No. 8) andHexadecafluorosebacic acid (No.9) were used asco-extractants with crown ethers in expectation ofcooperative effects. In the experiment (1), thesolubility of these co-extractans in HFC wasstudied in room temperature. Thought, No.7 toNo.8 compounds were difficult to dissolve in
HFC media, even other compounds weredissolved over 0.02 M. In the experiment (2), thesolvent extraction of strontium by Dicyclohexyl18-crown-6 ether with dissolvable 6 coextractans as extractant, and HFC as diluent
was studied.

1A09 Analysis of time-course change of Sr-90
and Cs-137 in environment by radioactive
concentration in teeth of cattle as an indicator.
KOARAI, K.1, KINO, Y.1, NISHIYAMA, J.1,
TAKAHASHI, A.2, SUZUKI, T.2, 3, SHIMIZU,
Y.2, CHIBA, M.2, OSAKA, K.2, 3, SASAKI, K.2,
FUKUDA, T.3, ISOGAI, E.3, OKA, T.1, 5,
SEKINE, T.1, 5, FUKUMOTO, M.6 and
SHINODA, H.2(1 Department of Chemistry, Tohoku University,
2
Graduate School of Dentistry, Tohoku University,
3
International Research Institute of Disaster
Science, Tohoku University, 4Graduate School of
Agricultural Science, Tohoku University,
5
Institute for Excellence in Higher Education,
Tohoku University, 6Institute of Development,

Aging and Cancer, Tohoku University, Japan)
The concentrations of Sr-90 and Cs-137 of
the teeth of abandoned cattle that were released
into the fields in the evacuation area following the
Fukushima-Daiichi Nuclear Power Plant (FNPP)
accident were determined. The Sr-90 and Cs-137
concentrations varied from 25 to 235 mBq (g Ca)1
and 1 to 8 mBq (g Ca)-1. They showed a positive
relationship to pollution degrees of the areas
where the cattle resided after the accident. The Sr90 concentrations of each tooth was different
even for the same individual, and its difference
was related to the tooth development stage at thetime of the accident: a higher Sr-90
concentrations was found in teeth that were in theearly development stage, while a lower Sr-90
concentrations was given in teeth in the latedevelopment stage. The findings demonstrate that
Sr-90 is an excellent indicator to record timecourse of 90Sr pollution in the environment. On
the other hand, there is no difference of Cs-137
concentrations of teeth between early and latedevelopment stage. The mechanism of Cs-137
incorporation in teeth differ that of Sr-90
incorporation and it is required to observe forindicator to record time course of Cs-137
pollution in the environment.

and pure water injected for emergency corecooling. Consequently, fission products leachedfrom the fuel debris, which generated hugeamount of contaminated water. In addition,
limited concentration of actinide elements aredetected in the contaminated water, which may
give an impact for the future waste management.
Since seawater contains a lot of salts, colloids andsuspended matters, the leaching behavior withseawater is expected to be different from that withpure water. In this work, therefore, simulated fueldebris consisting of UO2-ZrO2 solid solution
doped with 137Cs, 236Pu, 237Np and 241Am tracers
were synthesized by a heat treatment, anddevoted for an agitated leaching test in natural
seawater or distilled water for comparison. Afterthe leaching test, leaching ratios were determinedby alpha or gamma ray spectrometries. Cs wasleached to seawater 30~40% but the leachingratio of actinides were very low (0.1% or less).
The effect of UO2 and ZrO2 ratio on the leachingratios were also investigated.

1A11 Atmosphere Dependence of Formation
Process of Oxygen Vacancies in Zinc Oxide
Doped with Al and In Impurities
KOMATSUDA, S.1,SATO, W.2, OHKUBO, Y.3(1Nat. Inst. Tech., Ichinoseki College, 2Inst. Sci.
Eng., Kanazawa Univ., 3Res. Reactor Inst., Kyoto
Univ.)
Thermal behavior of Al and In impurities
doped in zinc oxide (ZnO) was investigated bymeans of the time-differential perturbed angularcorrelation (TDPAC) method with the 111In(→
111Cd) probe. In one of our previous TDPAC
studies, we observed contrasting atmospheredependence of the stability of aggregations of111
In and Al impurities doped in 100 ppm Aldoped ZnO: (i) Al and In impurities associatewith each other by their thermal diffusion in air,and (ii) the 111In probe is detrapped from the Al
aggregations in high-temperature vacuum,

1A10 Leaching Behavior of Actinide Elementsfrom Fuel Debris
Hirano M.1, Kirishima A.2, Akiyama D.2, Sasaki
T.3, Sato N.2(1Tohoku Univ., 1Tohoku Univ. IMRAM, 3 Kyoto
Univ.)On March 2011, the loss of coolant
accident occurred at Fukushima Daiichi NPS,
because of the mega earth quake and the big
Tsunami. At the reactor cores, the melted fuels
were thought to have reacted with Zr claddings.
As a result, a solid solution of uranium andzirconium oxides called fuel debris were
expected to be formed (=ZryU1-yO2). Seawater153

resulting in substitution at defect-free Zn sites.
Detailed investigation of the thermal behavior of
the impurities has revealed that the dissociation
reaction is triggered by the formation of oxygen
vacancies. Furthermore, the formation energyof oxygen vacancy was evaluated from thetemperature variation of the rate constants, which
was estimated from the annealing timedependence of TDPAC spectrum. In the session,
based on the further investigation of TDPAC
spectra for Al-doped ZnO obtained by isochronalannealings in Ar gas atmosphere, we discuss theatmosphere dependence of the formation energyof oxygen vacancy.

1A12 First detection of a missing spinel
ZnIn2O4 formed as nanostructures in ZnOSATO, W.1, KOMATSUDA, S.2, YAMADA, Y.3,
OHKUBO, Y.4(1Inst. Sci. Eng., Kanazawa Univ., 2Nat. Inst.
Tech., Ichinoseki College, 3Dep. Chem., Tokyo
Univ. Sci., 4Res. Reactor Inst., Kyoto Univ.)
Zinc oxide (ZnO) is an intrinsic n-typesemiconductor, and its physical properties arevariable with the presence of dilute impurities.
For future applications of this compound, it isthus important to investigate the way they are in
ZnO matrix. In a series of this work, we applied
time-differential perturbed angular correlation(TDPAC) spectroscopy with the 111Cd(←111In)
probe to a study of local fields in 0.5 at.% Indoped ZnO, and found that In ions form a uniqueminute structure dispersed in ZnO matrix. The
perturbation pattern of the TDPAC spectra
obtained for the In-doped ZnO allowed us to inferthat the unique structure is of a type of spinel. For
the purpose of obtaining further information on
the structure, in the present study, a DFT
calculation was performed for the evaluation of
the hyperfine parameters obtained by the above
experiments. It was found that the values of theelectric field gradient and its asymmetry

154

parameter at the Cd nucleus in the energetically
optimized structure show excellent agreementwith the experimental values within theiruncertainties. This result indicates the first
synthesis and detection of a binary spinel ZnIn2O4,
whose structure and property have been discussed
only in theory.

1A13 Annealing-Temperature
DependentInteraction of Vacancy-Type Defects with
Impurity Hydrogen in Single Crystal ZnO
Probed by Means of Positron Annihilation
Lifetime Spectroscopy
SHIMIZU, H.1, FUJISAWA, T.1, MIHARA, M.2,
SATO, W.1,3(1Grad. School Nat. Sci., Tech. Kanazawa Univ.,
2
Grad. School Sci., Osaka Univ., 3Inst. Sci. Eng.,
Kanazawa Univ.)
Zinc Oxide (ZnO) is well known to show
electrical conductivity. Because of its transparecy,
therefore, single crystal ZnO is highly expected
for applications to light emitting devices,transparent electrodes and so on. In general,commercially available ZnO is an n-typesemiconductor because hydrogen atoms
unwantedly mixed into ZnO through crystal
growth process work as a donor in ZnO. It isconsidered that the impurity hydrogen atoms
form complexes with zinc vacancy (VZn),
represented by VZn + nH, by coulombic attraction
between them, which could be a cause ofinactivation of VZn as an important contributor top-type semiconductivity of ZnO. The electricalconductivity of ZnO can be controlled by thevariation of the concentration of the hydrogen, i.e.
the carrier density, and it is thus essential toexamine interacting nature of VZn and impurity
hydrogen.
In this work, we introduced hydrogen ions
1 +( H ) into ZnO single crystal and observed thestate of the hydrogen atoms as impurities bymeans of positron annihilation lifetimespectroscopy. In the present session, we discuss
annealing-temperature dependent interaction
between VZn and 1H+ based on results of electricalconductivity measurements as well.

moiety.
On the other hand, we developed anexperimental method of replacing CH2Cl2 withother organic solvated molecules (Sol) in
forming
Fe3O(C6F5CO2)6(C5H5N)3·CH2Cl2,
Fe3O(C6F5CO2)6(C5H5N)3·Sol,
where Sol =benzene, toluene, xylene, pyridine, and so on.
In the present work, the Mössbauer spectra andpowder XRD patterns were measured forFe3O(C6F5CO2)6(C5H5N)3·Sol, in order to clarify
furthermore such relationship between thevalence-fluctuation and the Fe3O structures.

1A14 Mössbauer spectroscopic study ofvalence-trapping/detrapping in mixed-valence
trinuclear
iron
pentafluorobenzoate
complexes, forming two polymorphs andhaving crystalline solvated molecules
SAKAI, Y.1, OGISO, R.1, NAKAMOTO, T.2,1,
KAWASAKI, T.3, KITAZAWA, T.3,
TAKAYAMA, T.1, TAKAHASHI, M.3(1Daido Univ., 2Toray Research Center, 3Toho
Univ.)We have studied valence-fluctuation
behaviors in mixed-valence trinuclear ironpentafluorobenzoate
complex57
Fe3O(C6F5CO2)6(C5H5N)3 by Fe Mössbauer
spectroscopy. This electrically-neutral complex
was synthesized with dichloromethane as a
crystalsolvatemolecule,
Fe3O(C6F5CO2)6(C5H5N)3·CH2Cl2, which wasreported to be a novel compound by us in 2012,
together with the Mössbauer data.
It wasrevealed in our recent work that the
Fe3O(C6F5CO2)6(C5H5N)3·CH2Cl2 complex have
two polymorphs; hexagonal and orthorhombic
forms. By single crystal X-ray structure analysis,in the former three bond lengths (Fe-O) and bondangles (Fe-O-Fe) in a central Fe3O moiety wereshown to be equivalent one another, while in thelatter they ware proved to be non-equivalent.
Mössbauer measurements showed that the roomtemperature valence-state of three iron cations in
the hexagonal form is detrapped, i.e., only
averaged-valence iron Fe2.7+ being observed, andthat the valence-trapped state (Fe3+ and Fe2+
observed discretely) is found in the orthorhombic
form at room temperature. This finding implies
that the iron-valence fluctuation should be
influenced by structures of the central Fe3O

1A15 Spatial variation of the FDNPP-derived
Cs in coastal/offshore areas of Niigata
UEMURA, H(LLRL, Kanazawa Univ.)
We collected a total of 13 marine sedimentcore (10 cm) samples in the coastal and offshore
areas (40-520 m depths) in the Sea of Japan-sideof central of Honshu Island in July 2014 during
the R/V Soyo Maru expedition and examinedlateral and vertical profiles for concentrations of137
Cs (half-life: 30.2 y) and 134Cs (half-life: 2.06y) in this area. The concentration of 134Cs (0-7
Bq/kg-dry) at the surface (0-1 cm depth)
decreased sharply towards the offshore area andalong the coastline from the vicinity of an estuaryof Agano River. Near an estuary of Agano River,134
Cs has reached to 10 cm depth within 3 y after
the Fukushima Dai-ichi Nuclear Power Plant
accident.
134

1A16 Chemical species of cesium in suspended
particles in seawater
MIURA, H.1, KURIHARA, Y.1, HIGAKI, S.1,
ISHIMARU, T.2, KANDA, J.2, TAKAHASHI, Y.
1(1The Univ. of Tokyo, 2Tokyo Univ. Marine Sci.
Technol.)Chemical species of radiocesium adsorbed

155

on sinking particles and suspended particles inseawater and that in river water was studied. In
particular, their affinity to Cs was examined
before and after the removal of organic matterassociated with the particles by leachingexperiments, Cs speciation by EXAFS, andcharacterization of organic matter by scanningtransmission X-ray microscope (STXM). It was
found that Cs-137 newly added and adsorbed tothe particles can be leached by the addition of 1
M NH4Cl solution.
However, the leachedfraction decreased when Cs-137 was adsorbed on
the particles after the removal of organic matterfrom particles by hydrogen peroxide solution.
Solid-water distribution coefficient (Kd) of Cs on
the particles increased and inner-sphere complexof Cs in the particles increased by the removal oforganic matter from the particles, showing that Cs
affinity for the organic-free particles, presumably
clay minerals, is high.
Original Cs-137
incorporated in the particles was not leached by 1
M NH4Cl solution both in the absence andpresence of organic matter, which shows that Cs137 was adsorbed on the particles before its
migration into seawater.

radioactivity in water samples at fixed stations(Date and Iwanuma) in the lower Abukuma River,Japan after the Fukuhsima Dai-ichi Nuclear
Power Plant accident.
The radiocesium activity concentration had
a decreasing trend with increasing time at normal
flow condition during May 2011- February 2015
after the accident, though the highest radiocesium
activity concentrations were observed after rain
events. The percentage of 134Cs and 137Cs
associated with riverine suspended solids was 2989% with an average of 70 ± 18% at normal flow
condition, but ranged from 84 to 99% and an
average of 96 ± 6% at high flow condition due torain events. These results indicate that rain events
are a main factor controlling the transport flux ofradiocesium associated with suspended solids inriver waters from the lower Abukuma River.

1A17 Study on transport behavior ofradiocesium in the lower Abukuma River after
the Fukushima Dai-ichi Nuclear Power Plant
accident
NAGAO, S. 1, SHIMAMURA, A. 1, TADOU,
S. 1, UEMURA, H. 1, KANAMORI, M. 1,
MIYATA, Y. 1, OCHIAI, S. 1, KIRISHIMA, A.
2(1Kanazawa Univ., 2Tohoku Univ.)
The secondary radioactive dispersion ofradiocesium from the contaminated watershed to
the river waters is important to understand themigration behavior of 134Cs and 137Cs in river
systems running through the areas with widely
various radiocesium deposition on groundsurfaces. This study investigated 134Cs and 137Cs

156

1A18 Relationship between radiocesium
interception potential (RIP) and various
factors such as cation exchange capacity,
specific surface area, organic carbon content,
and mineral composition for suspended
sediment in river water
TAKAHASHI, Y.1, KURIHARA, Y.1, FAN, Q.1,
TANIGUCHI, K.2, MIURA, H.1, ONDA, Y.2(1The Univ. of Tokyo, 2Univ. of Tsukuba)
Characterization of 62 suspended sediment
samples collected from rivers in Fukushima andMiyagi Prefectures were conducted including
solid-water distribution coefficient (Kd),radiocesium interception potential (RIP), cationexchange capacity (CEC), specific surface area(SA), organic carbon content (OC), and mineralcomposition (in particular, mica (M) and quartz(Q) ratio). The correlation of RIP with Kd, CEC,
SA, OC and M/Q ratio were examined bymultiple regression analysis. It was found that
RIP is positively correlated with CEC, SA, and
M/Q, while negatively correlated with OC, which
was not clearly observed by 1:1 correlation of RIP

to each parameter.

first experimental determination of the IP valuesof Fm and Md.

1B01 Measurement of the first ionizationenergies of fermium (Fm, Z=100) andmendelevium (Md, Z=101)
SATO, T. K.1, ASAI, M.1, KANEYA, Y. 1,2,
TSUKADA, K. 1, TOYOSHIMA, A. 1, TAKEDA,
S.3, MITSUKAI, A. 1,2, NAGAME, Y. 1,
ICHIKAWA, S.4, MAKII, H.1, OSA, A.1,
SAKAMA, M.3, OOE, K.5, SATO, D.5,
SHIGEMATSU, Y.6, STORA, T.7, DÜLLMANN,
Ch. E.8, SCHÄDEL, M.1, KRATZ, J. V.8(1JAEA, 2Ibaraki Univ., 3Tokushima Univ.,
4
RIKEN, 5Niigata Univ., 6Osaka Univ., 7CERN,
8
Univ. of Mainz)
The first ionization energies (IPs) of heavy
elements with atomic numbers Z > 100 have notbeen measured due to their short half-lives andlow production rates. In order to determine IPs ofheavy elements experimentally, we havedeveloped a novel measurement method based ona surface ionization technique coupled to a
He/CdI2 gas-jet transport system in the Isotope
Separator On-Line (ISOL) at the JAEA tandem
accelerator facility. In this work, we havedetermined IP values of Fm (Z = 100) and Md (Z= 101). In a surface ionization process, anionization efficiency of an atom depends on its IP.
To obtain a relationship between IP and
ionization efficiency in the present system, we
measured ionization efficiencies of short-lived
isotopes, 80Rb, 157Er, 162Tm, 168Lu, 142,143Eu,
143m
Sm, 148Tb, 153,154Ho, 165Yb, and 49Cr.
Ionization efficiencies of 249Fm and 251Md,
produced in the 243Am(11B, 5n) and 243Am(12C,4n) reactions, respectively, were also measured.
Measured ionization efficiencies of 249No and251
Md were 1.2 %. From these ionization
efficiencies of Fm and Md, their IP values were
determined based on the relationship between of
IPs and ionization efficiencies in the present
system. In the presentation, we will report on the

1B02 Adsorption Behavior of Elements in
Surface Ionization: Towards Measurement of
Adsorption Enthalpy of Lawrencium (Lr)
KANEYA, Y.1,2, SATO, K, T.2, ASAI, M.2,
TSUKADA, K.2, TOYOSHIMA, A.2, NAGAME,
Y.1,2, OOE, K.3, MIYASHITA, S.4, OSA, A.2,
EICHLER, R.5,
(1Ibaraki Univ., 2Japan Atomic Energy Agency,
3
Niigata Univ., 4Hiroshima Univ., 5Paul Scherrer
Institute)
Due to strong relativistic effects, theground state electronic configuration of theheaviest actinide, lawrencium (Lr), is predicted to
be [Rn]5f147s27p1/2, which is different from thatof the lanthanide homolog Lu [Xe]4f146s25d.
According to the semi-empirical calculations
based on the electronic configuration, thevolatility of Lr is higher than that of Lu. Here wehave investigated adsorption behavior of Lr
together with various short-lived lanthanide
isotopes using a surface-ionization technique thatare produced in heavy-ion induced nuclear
reactions at the JAEA tandem accelerator. The
results suggest that the adsorption of Lr on a Ta
surface is smaller than that of Lu, indicating thatthe volatility of Lr is higher than that of Lu as
expected.

1B03 Spectroscopy of low-energy conversion
electrons to investigate the deexcitation
process of 235mU
SHIGEKAWA, Y. 1, KASAMATSU, Y. 1,
YASUDA, Y. 1, SHINOHARA, A. 1
(1Grad. Sch. Sci., Osaka Univ.)
The 235mU nuclide has very low excitationenergy (76.8 eV) and decays predominantly by
the internal conversion process. The deexcitation157

of 235mU involves the interaction between the
nucleus and outer-shell electrons. Indeed, thevariation of the decay constant of 235mU
depending on its chemical environment wasreported. We are aiming to clarify thedeexcitation process of 235mU by measuring the
decay constants and the energy spectra of theinternal-conversion electrons for various
chemical forms. In this work, we fabricated aspectrometer of low-energy conversion electronsof 235mU. The spectrometer is retarding-field type,and electrons can be detected at high efficiency.
We evaluated the performance of thespectrometer by measuring auger electrons of51
Cr and 48V. Then we prepared 239Pu sources,
and tried to measure decay constants and energy
spectra with the spectrometer for 235mU samples
collected from the 239Pu sources to Cu plates by
the Collection Apparatus for Recoil Products.
The decay constants were determined for
different 235mU samples.

different chemical forms: fluoride and hydroxide.
Thorium-229m was separated from its mothernuclide, 233U, by anion-exchange separation.
Then, 229mTh was coprecipitated with samarium
and the photon detection was performed in theenergy range 4-10 eV. For the hydroxide andfluoride samples of 229mTh grown for about 2 h,no significant photon emission was observed. In
the case of the 229mTh samples grown for about 13h, the photon counts decaying for time weredetected. However, these decaying photons
possibly originate from the daughter nuclides,
such as Bi or Pb. Indeed, photons were notobserved for purified 229mTh samples. In addition,
we tried photon detection for 229mTh implanted
into MgF2 glass.

1B04 Search for the vacuum ultraviolet
photons emitted from 229mTh samples
Yasuda, Y.1, Kasamatsu, Y.1, Shigekawa, Y.1,
Takamiya, K.2, Ohtsuki, T.2, Mitsugashira, T.3,
Shinohara, A.1(1Grad. Sch. Sci., Osaka Univ., 2Res. Reactor Inst.,
Kyoto Univ., 3The Oarai-branch, Inst. Materials
Res., Tohoku Univ.)
Thorium-229m lies in extremely low
energy level, 7.8 ± 0.5 eV, and this excitationenergy corresponds to vacuum ultraviolet light.
Because of such a low energy, it is expected that229m
Th deexcites interacting with its outer orbital
electrons, and the half-life and even the decay
mode of 229mTh depend on its chemical
environments. Recently, photon emissions fromthe 229mTh sample implanted into MgF2 glass
were reported and its half-life was evaluated to beabout 6 h. In this study, we report the results ofphoton detections of 229mTh samples with158

1B05 Ion-exchange experiments of Nb and Ta
in HF/HNO3 solution for identification offluoride species of Db
TOYOSHIMA,
A.1,
MITSUKAI,
A.1,2,MURAKAMI, M.3, SATO, D.3, MOTOYAMA,
R.3, KOMORI, Y.4, HABA, H.4, ASAI, M.1,
TSUKADA, K.1, SATO, T. K.1, KANEYA, Y.1,2,
NAGAME, Y.1(1JAEA, 2Ibaraki Univ., 3Niigata Univ., 4RIKEN)
We have so far studied the anion-exchange
behavior of dubnium (Db) in 14 M HF and 0.3 M
HF/0.1 M HNO3 solutions; the adsorption
probability of Db was lower than those of Nb and
Ta in the former solution and was close to that of
Nb in the latter. In the present study, for
identification of fluoride species of Db, wefurther studied anion-exchange behavior ofgroup-5 element Nb and Ta in 1.0-24 M HF/2.0
M HNO3. In the experiment, carrier-free 95gNb
and 179Ta radioisotopes produced in the natZr(p,xn) and natHf(p, xn) reactions, respectively, wereseparated from the target materials by an ionexchange method. Batch-wise experiments with
95g
Nb and 179Ta were carried out in 1.0 - 24 M
HF/2.0 M HNO3 using the anion-exchange resin

CA08Y. Results showed that adsorption
probability of Nb on the resin sharply increases at> 6 M HF/2.0 M HNO3 while that of Ta gradually
decreases with increasing HF concentration. Thisbehavior suggests that Nb forms [NbF6]- and[NbF7]2- from [NbOF5]2- at > 6 M HF and Ta
exists as [TaF6]- and [TaF7]2- in the solution. In
conclusion, it is expected that chemical species of
Db could be identified with the anion-exchange
chromatography under the present conditions.

time (10–60 s) by using AMBER. After the
extraction, we measured alpha-particle for the
samples by using an automated rapid D/SF
detection system. We succeeded in theobservation of the equilibration of the extraction
reaction of Rf. The obtained Kd values of Rf wereclearly different from those of Zr, Hf, and Th.

1B06 Determination of the distribution
coefficients in the extraction of anionicchloride complexes of rutherfordium
YOKOKITA,
T.1,
KASAMATSU,
Y.1,
SHIGEKAWA Y.1, YASUDA, Y.1, NAKAMURA,
K.1,
KINO,
A.1,
TOYOMURA,
K.1,
TAKAHASHI, N.1, HABA, H.2, KOMORI, Y.2,
MURAKAMI, M.3, YOSHIMURA, T.4,
SHINOHARA, A.1(1Grad. Sch. Sci., Osaka Univ., 2Nishina Center,
RIKEN, 3Fac. Sci., Niigata Univ., 4Radioisotope
Res. Center, Osaka Univ.)
To investigate chloride complexation ofelement 104, rutherfordium (Rf), we studied
extraction behaviors of its homologous elements(Zr and Hf) and pseudo homologue (Th) in an
Aliquat 336/HCl system. In addition, wedeveloped a batch-type solid-liquid extraction
apparatus for online use(AMBER) to
investigate time dependences of the extraction
behavior of Rf and determine the distribution
coefficient (Kd) of it. In this study, we performed
online solid-liquid extraction experiment of 261Rf
and 169Hf in an Aliquat 336/HCl system. These
nuclides were simultaneously produced in thebombardment of 248Cm and natGd mixture target
with 18O beams delivered from an AVF cyclotron
at RIKEN. The products were continuouslytransported to the chemistry room with a He/KCl
gas-jet system. We performed solid-liquid
extraction of these elements with various shaking

159

1B07 Development of a flow solvent
extraction apparatus coupled to the GARIS
gas-jet system for aqueous chemistry ofsuperheavy elements
KOMORI, Y.1, HABA, H.1, OOE, K.2 ,TOYOSHIMA,
A.3,
MITSUKAI,
A.3,
MURAKAMI, M.2, SATO, D.2, MOTOYAMA,
R.2, YANOU, S.1, WATANABE, K.1,
SAKAGUCHI,
A.4,
KIKUNAGA,
H.5,
OMTVEDT, J. P.6(1Nishina Center, RIKEN, 2Grad. School of Sci.
and Technol., Niigata Univ., 3JAEA, 4Univ. of
Tsukuba, 5ELPH, Tohoku Univ., 6Oslo Univ.)
Toward aqueous chemistry of the heaviest
superheavy elements such as element 106, Sg andelement 107, Bh, we have been developing a
rapid solvent extraction apparatus which consistsof a continuous dissolution apparatus (Membrane
DeGasser: MDG), a Flow Solvent Extractor(FSE), and a flow liquid scintillation detector for
α/SF-spectrometry. As a preseparator for thischemistry apparatus, we plan to use the RIKEN
GAs-filled Recoil Ion Separator (GARIS). In thiswork, we studied the performance of MDG using
90m,g
Nb (m: T1/2 = 18.8 s; g: T1/2 = 14.6 h) and178a
Ta (T1/2 = 2.36 h) produced in the natZr(d,xn)
and natHf(d,xn) reactions, respectively, at the
RIKEN AVF cyclotron. It was found that the
dissolution efficiency of the short-lived 90mNb isaround 50% while those of the relatively longlived 90gNb and 178aTa are as high as over 80%.
FSE consists of a Teflon capillary and a phaseseparator with a membrane filter. We also studied
solvent extraction behavior of 95mTc (T1/2 = 61 d)

As a result, 160 D events (8.00-8.40 MeV)
from Rf and its daughter nuclide 257No wereobserved in 1001 cycles of the column
chromatography experiment. The percent
adsorption value of Rf was constant at around
60% at [F]  5.0u104 M and then steeply
dropped at [F] = 9.0u104 M, while those of Zr
and Hf showed decreases at [F] ! 4.0 u 105 M.
This suggests that the cationic fluoride complexesof Rf more stably exist than those of Zr and Hf at[F] ! 4u105 M.

and 183Re (T1/2 = 70 d) into tri-n-octylamine(TOA) in toluene from nitric acid solutions.
Distribution ratios of 95mTc and 183Re obtainedwith FSE were consistent with those by a batch
method.

261

1B08 Dependence on F concentration of
cationic fluoride complexation of super-heavy
element rutherfordium by using TTAreversed-phase chromatography
FUKUDA, Y.1, KITAYAMA, Y.1, HABA, H.2,
TOYOSHIMA, A.3, TSUKADA, K.3, KOMORI,
Y.2, MURAKAMI, M.2,4, KIKUNAGA, H.5, M.
H. HUANG.2, OOE, K.4, MITSUKAI, A.3,6,
UENO, S.1, TANIGUCHI, T.1, HAYASHI, K.1,
YATSU, Y.1, CHIYONISHIO, I.7, MURAKAMI,
K.7, OOE, S.7, MORIYA, K.7, YOKOYAMA, A.7(1Grad. School Nat. Sci. Tech., Kanazawa Univ.,
2
Nishina Center, RIKEN., 3JAEA., 4Grad. School
Sci. Tech., Niigata Univ., 5Research Center for
Elec. Photon Sci., Tohoku Univ., 6Grad. School
Sci. Tech., Ibaraki Univ., 7Inst. College. Sci. Eng.,
Kanazawa Univ.)
We have so far developed a reversedphase-chromatography technique with TTA as achelating extractant to clarify properties of acationic fluoride-complex of rutherfordium (Rf).
In this study, we studied elution behavior of Rf in
HF/HNO3 solutions by this technique. 261Rf was
produced in the 248Cm(18O, 5n)261Rf reaction at
the RIKEN K70 AVF cyclotron. 89m,85Zr and
175,169
Hf, short-lived nuclides of lighter homologsof Rf, were also produced in the natY(d, xn)89mZr,nat
Gd(18O, xn)85Zr, natLu(d, xn)175Hf, natGd(18O,xn)169Hf reactions, respectively. Reaction
products were rapidly transported with a KCl/He
gas-jet system to the chemistry laboratory.
TTA-chromatographic behavior was investigatedin HF/0.01M HNO3 solutions using theautomated rapid chemistry apparatus (ARCA)
and the rapid D/SF detection system for aqueous
chemistry of super-heavy elements at RIKEN.

1B09 Extraction behavior of Mo and W from
H2SO4 into toluene with Aliquat336 as modelexperiments for seaborgium (Sg)MITSUKAI,
A.1,2,TOYOSHIMA,
A.2,
KANEYA, Y.1,2, OOE, K.3, SATO, D.3,
MURAKAMI, M.3, KOMORI, Y.4, HABA, M.4,
ASAI, M.2, TSUKADA, K.2, SATO, T.K.2,
NAGAME, Y.2(1Grad. Sch. Sci. and Eng., Ibaraki Univ., 2JAEA,
3
Grad. Sch. Sci and Tech., Niigata Univ.,
4
RIKEN)We have started studying sulphatecomplex formation of a transactinide element,
seaborgium (Sg). In this study, we report on theextraction behavior of carrier-free radioisotopes
93m
Mo (T1/2 = 6.85 h) and 181W (T1/2 = 121.8 d)which are lighter homologs of Sg, from aqueous
H2SO4 solution with amine extractant,Aliquat336, dissolved in toluene by a batch
method. These radioisotopes were produced in
the natZr(α, 2n) and 181Ta(d ,xn) reactions at the
RIKEN K70 AVF cyclotron. Results of theextraction experiments showed that the
distribution ratios of Mo and W increase sharply
above ~ 3.0 M H2SO4. Based on the slope analysis
separately carried out, it was indicated thatanionic sulphate-complex of [MO2(SO4)2]2- (M =Mo, W) are formed in > 5 M H2SO4. These results
suggest that the present system is applicable tothe extraction of Sg. In the symposium, we will

160

Technology, 4National Metrology Institute ofJapan)
Pu leaching with nitric acid is widely
employed to determine global fallout Pu in solid
samples, i.e. soil and sediment. At sampling
ashing step to decompose organic matter, various
temperatures (400 – 900˚C) are used. However,
the effect of temperature on the accurate Pu
analysis has not been well investigated. In thisstudy, we used two standard reference soils(IAEA-soil-6 and IAEA-375) and Pu
determination was carried out after ashing at
various temperatures from 375-600˚C. The
results showed that 239+240Pu activity was lower
than the certified value when the ashingtemperature exceeded 450˚C, and the 239+240Pu
activity continue to decrease as the ashingtemperature raised. Approximately 40% Pu could
not be leached out by concentrate HNO3 after
ashing for 4 h at 600˚C. The Pu loss was
attributed to the formation of refractory materials,
which are insoluble in HNO3 solution. Thishypothesis was confirmed by the XRD analysisof ashed soil samples which revealed thatplagioclase-like silicate materials were formed
after high temperature ashing. To ensure the Pu
release efficiency in HNO3 leaching, we
recommend 450˚C as the ideal ashingtemperature.

also show the present status of the developmentof a new solvent extraction apparatus for future
Sg experiments.

1B10 Estimation of Carbon Transfer from Soil
to Plant using Stable Isotope Ratio
TAGAMI, K.1, UCHIDA, S.1, ISHII N.1(1National Institute of Radiological Sciences)
The aim of this study is to estimate soil
carbon-14 (14C, half-life: 5730 y) transfer to crop
considering deep underground TRU waste
disposal because 14C is an important radionuclide
in the radiation dose assessment. The soil to planttransfer factor (TF) is used in the assessment and
TF is calculated as a ratio of concentration in crop
divided by that in soil. For the case of carbon, TF
was calculated from stable carbon mass so thatthe value was extremely high; however, it did notreflect the real carbon cycle, i.e. plant
photosynthesizes CO2 from the air, and the effectfrom soil to plant was not clear. Moreover, only alimited numbers of radiotracer experiment data
were available. To obtain TF in the field
conditions, we measured stable carbon isotope
ratio, G13C, in crop and associated soil samples to
identify whether we could find any correlations
between soil G13C and crop G13C. There was nocorrelation for leafy vegetables and tubers, andonly a low correlation was found for rice. Thus
we concluded that only a negligible amount ofsoil carbon would be used in plants. We didfurther analysis and the results on estimatedcarbon TFs will be presented.

1B12 Radiocesium accumulation and Pu
isotopes source identification in sedimentsfrom Lake Inba, Japan after the Fukushima
Daiichi Nuclear Power Plant accident
CAO, L.1,2, ISHII, N.1, ZHENG, J.1, TAGAMI,
K.1, UCHIDA, S1., KAGAMI, M.3(1Natl. Inst. Radiol. Sci., 2Nanjing Univ., 3Toho
Univ.)
To investigate the vertical distributions of137
Cs and Pu in lake sediments after the
Fukushima Daiichi Nuclear Power Plant(FDNPP) accident, two sediment cores were

1B11 Effect of ashing temperature on accurate
determination of plutonium in soil samples
WANG, Z.T.1, YANG, G.S.1, ZHENG, J1, CAO,
L.G.1,2, YU, H.J.3, ZHU, Y.B.4, TAGAMI, K.1,
UCHIDA, S.1(1National Institute of Radiological Sciences,
2
Nanjing Univ., 3Beijing University of161

collected on 11 August 2011 (Core-1) and 30 July2012 (Core-2) at the same position in Lake Inba.
Radiocesium (134Cs, 137Cs) were measured by aGe-detecting system, and Pu isotopes (239Pu,
240Pu) were analyzed by SF-ICP-MS afterradiochemical separation. The 134Cs/137Cs activity
ratios of upper layers in the two sediment cores
were approximately 1 (decay corrected to 15
March 2011), suggesting that the FDNPP
accident-derived radiocesium have contaminatedthe samples. For Core-1, 137Cs inventory wascalculated to be 32300 ± 660 Bq/m2. For core-2,
collected about one year later, the 137Cs inventory
did not change much with the value of 37500 ±330 Bq/m2. The activities of 239+240Pu ranged
from 0.007 to 0.298 Bq/kg, which wascomparable with that of freshwater lake andmarine sediments around Japan before FDNPP
accident. The atom ratios of 240Pu/239Pu around0.18 indicated that global fallout was the main
source for Pu contamination in lake sediments.

aerosols and spontaneous fission source toelucidate a roll of chemical and physical effects
in a generation mechanism of radioactive
aerosols. Attachment ratios of fission products on
the solution aerosols were compared among theaerosols generated by different solutions. It was
found that proportional relationship exists
between the attachment ratios and the total
surface area. In comparison of slopes of therelationship, there found a significant difference
according as a solute of solution aerosols. The
difference according to the solute shown in thepresent work suggests the existence of chemical
effect in the attachment behavior of fission
products on solution aerosols.

1B14 Survey of contamination of radionuclide
released from the Fukushima DNPP accident Construction of database Saito-Kokubu, Y.1, Momoshima, N.2, Hirose, K.3,
Tagami, K.4, Takamiya, K.5(1JAEA-Tono, 2Isotope center, Kyushu Univ.,
3
Sophia Univ., 4Natl. Inst. Radiol. Sci., 5Res.
Reactor Inst., Kyoto Univ.)
Just after an accident at the Fukushima
Daiichi Nuclear Power Plant (FDNPP), data ofradionuclides released from the FDNPP were
measured for environmental samples by someresearchers at individual research institute anduniversity. However a comprehensive databaseincluding these data is not constructed now.
Working group of the Japan Society of Nuclear
and Radiochemical Sciences decided to construct
a comprehensive database of data of theradionuclides in environmental samples. This
database contains data such as sampling location,
sampling method, sampling times, type ofmeasurement system, concentrations of theradionuclides
andothersinthepublications/reports and unpublished issues.
Researchers input the data in a dedicated Excel
sheet. The working group verifies and registers

1B13 Attachment behavior of fission products
on solution aerosol
TANAKA, T.1, TAKAMIYA. K.2, NITTA, S.1,
SEKIMOTO, S.2, OKI, Y.2, OHTSUKI, T.2(1Grad. School of Eng., Kyoto Univ., 2 Res.
Reactor Inst., Kyoto Univ.)
Various characteristics such as size
distribution,
chemicalcomponent
andradioactivity have been analyzed for radioactive
aerosols released from Fukushima Daiichi
Nuclear Power Plant. Measured results forradioactive aerosols suggest that the potential
transport medium for radioactive cesium was
non-sea-salt sulfate. This result indicates that
cesium isotopes would preferentially attach withsulfate compounds. In the present work theattachment behavior of fission products on
aqueous solution aerosols of various salts, such as
NaCl, NaBr, NaI, KCl and CsCl, has been
observed using a generation system of solution

162

327 mg/cm2) in order to evaluate a production
yield of 67Cu and a quality of the purified 67Cu.
Under the present experimental condition, theyield of 67Cu was 4.0 MBq μA–1h–1. We estimatedthat about 1 GBq of 67Cu could be distributed
after a 3-days irradiation with a 10-μA deuteronbeam, followed by 3 days for chemical separationand shipment.

the data in the database, and then summarizes
them in a scientific report.
As the first stage of the construction of thedatabase, data containing the concentrations of
the radionuclides in airborne particles is handled.
The concentrations of the FDNPP-derived
radionuclides in surface air were measured at
Chiba, Saitama, Ishikawa, Aichi and Fukuoka.
Temporal variation of their concentrations let us
estimate atmospheric motion of radioactive
plume released from the FDNPP.

1B16 Production and Purification of Medical
Radioisotope Y-90 with accelerator neutrons
by deuterons
TSUKADA, K. 1, SATO, T. K. 1, HASHIMOTO,
K. 1, SAEKI, H. 1, HATSUKAWA. Y. 1, NAGAI,
Y. 1, WATANABE, S. 1, ISHIOKA, N. S. 1,
TAKEDA, S. 2
(1Japan Atomic Energy Agency, 2 Dep. of HealthBio. Sci., Univ. of Tokushima)
A new system has been proposed for thegeneration of radioisotopes with accelerator
neutrons by deuterons, especially the productionof 90Y (T1/2 = 64 h), which has been used for the
nuclear medicine. Enriched 90Zr nitrate samples
were irradiated with neutrons, which wereobtained by the natC(d,n) using 40 MeV deuterons
provided from the TIARA cyclotron. 90Y wassuccessfully produced via the (n, p) reaction, andseparated from the Zr nitrate target by threecolumns method with a hydrochloric acid. The
chemical procedure was done within 6 hours, andthe chemical yields was about 85%. The
separation factor between Y and Zr was obtained
to be <2x10-5 by using a J-ray spectrometry. Afterthe separation 90% of the target material wasrecovered from the column with 4 M HNO3
solution for the next irradiation. After the
purification, a labelling of DTPA with 90Y had
been performed. In this result, the yield was about
90% under >2.5 PM of DTPA, although the yields
were decreased at the DTPA concentration below
2.5 PM.

1B15 Production of 67Cu using the70
Zn(d,αn)67Cu reaction
YANO, S.1, HABA, H. 1, SHIBATA, S. 1,
KOMORI, Y. 1, TAKAHASHI, K. 1, WAKITANI,
Y. 2, YAMADA, T. 2, MATSUMOTO, M. 2
(1RIKEN Nishina Center, 2Japan Radioisotope
Association)
Since 2007, we have distributed purified
radioisotopes such as 65Zn, 85Sr, 88Y, and 109Cd
prepared at RIKEN Nishina Center for the
purpose of contribution to society throughout
industrial application of accelerator basedscience. Copper-67 (T1/2 = 61.83 h, Iβ- = 100%) is
one of the promising radioisotopes forradiotherapy and radiodiagnosis. In this work, forthe future distribution of 67Cu, we investigated anovel procedure to prepare the purified 67Cu
using the 70Zn(d,αn)67Cu reaction.
Radiotracers of 61Cu, 66Ga, and 69mZn were
produced in the natZn(d,X) reactions with a 24MeV deuteron beam delivered from the RIKEN
AVF cyclotron. After the irradiation, wedeveloped the two-step chromatographic
separation with Eichrom Cu resin and Dowex
1X8 anion-exchange resin. A chemical yield of
Cu was 93%, and decontamination factors of Ga
and Zn were > 2.6×104 and > 1.6×104,
respectively. A separate irradiation was
performed for an enriched 70ZnO target (70Zn
isotopic abundance: 96.87%; target thickness:

163

2

IMRAM, Tohoku Univ.)
DNA is an important substance that carries
genetic information of living organisms. WhenDNA is exposed to intense radiation, the DNA
strands break. This may cause a wrong
transcription of its base sequence and eventuallyharmful influence on a human body. The concern
on radiation-induced DNA strand break is
growing rapidly but its mechanism remains
unclear at a molecular level, leading todifficulties in scientific discussions on radiation
damage.
Various model DNAs which have a small
number of base pairs and two linkers bridging theends of the short strands have been synthesized as
prototypes of DNAs. In this work, we performed
chemical reaction dynamics simulations for
short-strand DNAs to elucidate the mechanismsof strand breaks. For example, we optimized thestructure of a model DNA composed of 4
adenine-thymine base pairs and gave initially athermal energy of 0.4 eV/atom excluding linkers.
We found that single-strand breaks, which mainly
occur on the thymine side, consisted of two bondbreaking processes:(i) Hydrogen transfer from a sugar and toan adjacent phosphate followed bycleavage between the sugar and its
adjacent thymine(ii) Cleavage between the sugar and thephosphate induced by energy and chargetransfers from other nucleotides

1B17 Studies on PET imaging of cancer using
Cu-64 ions
SUGO, Y.1, OHSHIMA, Y.1, YAMAGUCHI, A.2,
HANAOKA, H.2, ISHIOKA, N. S.1(1JAEA, 2Gunma Univ.)
Copper-64 (64Cu) is an attractive
radionuclide for positron emission tomography(PET) imaging due to its half-life (12.7 h) anddecay characteristics. We proposed a new
approach to the PET imaging of cancer using 64Cu
ions without any labeling process. In this study
the usefulness of 64Cu ions as a PET imaging
agent was evaluated.
No-carrier-added 64Cu was produced by the
nuclear reaction of 64Ni(p,n)64Cu at high specificactivity, using the AVF cyclotron of Takasaki Ion
Accelerators for Advanced Radiation Application
facility at Japan Atomic Energy Agency.
The twelve kinds of cancer cells routinely
cultured were each incubated with 64Cu ions in
the medium at 37ºC. After incubation the cells
were thoroughly washed and their radioactivity
was measured. The specific cellular uptake of64
Cu ions was observed in the several kinds ofcancer.
The cancer-bearing mice were prepared by
subcutaneous injection of the cancer cells. The
mice were subjected to a small-animal PET
imaging at different time points after injection of64
Cu ions via the tail vein. The biodistribution
study was further performed. It was demonstrated
that the cancer could be successfully visualizedon the PET images due to the quite high uptakeof 64Cu in the cancer tissue.

2A01 Productionofneutron-deficient
rutherfordium isotopes in the 208Pb + 48,50Ti
reactions
AONO, R.1,2, GOTO, S.2, KAJI, D.1,
MORIMOTO, K.1, HABA, H.1, MURAKAMI,
M.2, OOE, K.2, KUDO, H.3(1RIKEN Nishina Center, 2Grad. Sch. Sci. Tech.,
Niigata Univ., 3Fac. Sci., Niigata Univ.)
In order to clarify a nuclear fission

1B18 DNA strand break caused by charge andvibrationalenergytransfer
between
nucleotides: Reaction dynamics approach
HISHINUMA, N.1, KANNO, M.1, KINO, Y.1,
AKIYAMA, K.2, KONO, H.1(1Dept. Chem., Grad. Sch. Sci., Tohoku Univ.;

164

nucleus 261Rf was produced with the248
Cm(18O,5n) reaction at the JAEA Tandem
accelerator facility. Reaction products weretransported with a gas-jet transport technique to arotating-wheel alpha-gamma detection system.
Two gamma lines associated with the alpha decayof 261Rf were clearly observed, and more precisealpha-energy spectrum than before were obtained.
It was found that the literature value (8.28 MeV)of the alpha-transition energy of 261Rf wasincorrect, and that the alpha-decay scheme of261
Rf should contain several low-energy cascade
gamma transitions. On the basis of these results
and literature data of 261mRf , we will discuss
nuclear structure of superheavy nuclei around thisregion as well as the level structure of 261Rf andits daughter nucleus 257No.

mechanism, our group is planning a systematic
study of fission characteristics of Rf that has
relatively a large number of spontaneously
fissioning isotopes. In this study, we measured
decay events of especially neutron-deficient Rf
isotopes under low background.
Experiments were performed at the RIKEN
linear accelerator (RILAC) facility using a gasfilled recoil ion separator, GARIS. Rf isotopes
were produced in the reaction of 208Pb + 48,50Ti.
208
Pb targets of approximately 300 μg cm–2 inthickness were prepared by vacuum evaporation
on a 60 μg cm–2 carbon foil. The beam energies
of 48Ti and 50Ti were 224.7-239.2 MeV and
203.5-270.0 MeV, respectively. The averageintensities of 48Ti and 50Ti were 350 pnA and 570
pnA, respectively. The sixteen targets were put ona wheel of 30 cm in diameter and the wheel was
rotated at 2000 rpm. In this experiments, we
adopted a target ID system to simultaneously
observe reactions at four beam energies using Al
degraders (0, 0.8, 2.0, and 3.0 μm) which were
installed on the beam upstream of the targets. Rf
nuclides produced in the 208Pb(48Ti, xn) and208
Pb(50Ti, xn) reactions were separated from thebeam particles and nuclear reaction byproducts
using GARIS, and were measured with a focal
plane detector box composed of a position
sensitive detector (PSD) and four silicondetectors (SSD). A preliminary analysis showsthat some events of 253Rf and 254Rf were observedin the reaction of 208Pb + 48Ti.

2A03 Study on hot fusion reaction of
Cm+48Ca→296Lv* using GARISKAJI, D.1, MORIMOTO, K.1, HABA, H.1,
WAKABAYASHI, Y.1, TAKEYAMA, M.1,2,
YAMAKI, S.1,3, TANAKA, K.1,4, HUANG, M.1,
KOMORI, Y.1, KANAYA, J.1, MURAKAMI,
M.1,5, KATORI, K.1, HASEBE, H.1, YONEDA,
A.1, YOSHIDA, A.1, TOKANAI, F.1,6,
YOSHIDA, T.1,6, YAMGUCHI, T.3, ASAI, M.7,
GAN, Z.8, Ma, L.8, GEISSEL, H.9, HOFMANN,
S.9, MAURER, J.9, FUJITA, K.1,10, NARIKIYO,
Y.1,10, TANAKA, T.1,10, YAMAMOTO, S.1,10,
MORITA, K.1,10(1Nishina Center, RIKEN, 2Grad. Sch. of Sci. andEng., Yamagata Univ, 3Grad. Sch. of Sci. andEng., Saitama Univ., 4Grad. Sch. of Sci. and Tech.,Tokyo Univ. of Sci., 5Grad. Sch. of Sci. and Tech.,
Niigata Univ., 6Fac. of Sci., Yamagata Univ.,
7
JAEA, 8IMP, 9GSI, 10Fac. of Sci., Kyushu Univ.)
In 2013, a gas-filled recoil ion separator
was employed to study the production of Lv(Z=116) isotopes in the hot fusion reaction of248
Cm+48Ca at the beam energy Elabo = 261.6 MeV.
As a result, five correlated decay chains were248

2A02 Alpha-decay spectroscopy of 261Rf
ASAI, M.1, TSUKADA, K.1, SATO, N.1, SATO,
T.K.1, TOYOSHIMA, A.1, ISHII, T.1,
MIYASHITA, S.1, KANEYA, Y.1, SHIMA, Y.2,
SHIBATA, M.3(1JAEA, 2,3Nagoya Univ.)
Alpha-gamma coincidence and highresolution alpha fine-structure measurements
were performed for the alpha decay of 261Rf. The

165

observed. On the basis of the assignments of theprecedent studies by both Dubna-Livermore
collaboration and GSI SHIP collaboration, one of
the events was attributed to the decay of 293Lv(3n), and three of them were assigned to the
decays of 292Lv (4n).
With the aim of clear identification of these
nuclides, we started to measure the excitation
function. The 248Cm target was irradiated with a
258 MeV 48Ca11+ beam from RIKEN heavy-ion
linear accelerator. Total beam dose was 5.0×1018
during a net irradiation time of 14.2 days. As aresult, two correlated decay chains were observed.
One of the events is attributed to the decay of293
Lv. The other is not able to assign clearly,
although it is decay chain originating from thereaction of 248Cm+48Ca→296Lv*.
We will report about the decay propertiesof observed chains and the excitation function
including performance of background level andtransmission of GARIS for hot fusion reaction.

2A04 Measurement of (g,p)/(g,n) reaction
yield ratios and comparison of the results withcalculated values
KIKUNAGA, H., TSUKADA, K., SUDA, T.
(ELPH, Tohoku Univ.)
The (g,p) reactions play an important rolein the production of carrier-free radioisotopes
from targets irradiated with bremsstrahlung.
However, there is not enough experimental dataon the cross sections of the (g,p) reactions toestimate the amount of radioactivity produced in
the bremsstrahlung irradiation. In this study, we
have compared the experimental and calculated
reaction yield ratios of (g,n) to (g,p) reactions
which occur from a same nuclide to make surethat the cross section prediction code is used forthe estimation of the amount of the photonuclear
reaction
products.
The
bremsstrahlung
irradiations to the metal or oxide targets of 28Ni,
38Sr, 40Zr, 44Ru, 50Sn, 56Ba, 58Ce, 60Nd, 64Gd, 70Yb,

74W,

78Pt

were carried out using the linear
accelerator of Tohoku University. The accelerator
was operated at electron energies of 30 and 50
MeV with a mean current of around 0.03 mA.
After the irradiation, those targets were subjected
to gamma-spectroscopy to determined (g,n) and(g,p) reaction yield. We observed a wide range of(g,n)/(g,p) reaction yield ratios from 0.45 for 58Ni
to 127 for 176Yb at 50 MeV irradiation. The
comparison between the experimental andcalculated values is still in the process of analysis.

2A05 Half-life of Technetium-98
KOBAYASHI, T.
(College of Humanities and Sciences, Nihon
Univ.)The half-life of 98Tc was re-measured using
the isotope dilution method for determining thenumber of atoms, and J-ray spectrometry for
determining the absolute disintegration rate. The
proposal half-life is 6.2±0.6×106 y. The branchingration of EC to E- decay for 98Tc estimated to beless than 0.3% from the J-ray spectrometry.
In this work, two kind of samples wereprepared. First sample is a 99Tc source (37MBq)
purchased from Amersham Co. (TCS1). It was
prepared from fission products and contained 98Tc.
And the other sample was produced by 97Mo(d,n)98Tc reactions. A enriched 97Mo(92.9%) selfsupporting target was irradiated by the 14Mev d
beam for 12 hours in the cyclotron.

2A06 Elemental analysis of clay minerals
sample using Prompt Gamma ray Activation
Analysis method.
HATSUKAWA, Y., SUZUKI, S., YAITA, T.,
PAUL, R1.,
(JAEA, NIST1)
Research on desorption mechanism ofcesium ions in the clay mineral has been progress
on decontamination of radioactive cesium in166

Fukushima. In this investigation, trace elements
in clay minerals samples were determined using
prompt gamma ray activation analysis method
which is very sensitive multi-elemental
simultaneous determination method. The
experiments carried out at the research reactor in
the National Institute of Standards andTechnology (NIST). 25 clay mineral samples
including 6 standard samples were analyzed, and16 elements in the samples were determined. The
correlation of these elements will be discussed in
the conference.

clear peaks on the PGA and TOF spectra. On theother hand, a large number of peaks caused
interference with other peaks in simulated
samples. In this study, we will provide moredetails of analysis and experimental results.
This work was supported in part by Grantsin-Aid for Scientific Research (25246038).

2B01 Possibility of radiocarbon dating tobronze implement: Application to the metal
fittings installed in the rafter of main shrine of
Izumo-taisha
ODA, H.1, TSUKAMOTO, T.2, YAMADA, T 2(1Cen. Chronological Res., Nagoya Univ.,
2
Gangoji Institute Res. Cultural Property)
Verdigris is rust generated in bronze
implement. It is produced from Cu contain inbronze and CO2 in the atmosphere. Onceverdigris is formed, it has the property which
prevents formation of a new verdigris more. If
extraction and radiocarbon dating of the carbon
contained in verdigris become possible, the age inwhich the rust was formed is obtained, and also
estimation of the age for which bronze ware wasused may be realized. In this study, therefore, we
searched for the condition of carbon extraction
from verdigris. Verdigris is decomposed byheating in an evacuated glass tube. As the result,it became clear by heating at 1 h and 250℃ or
more that CO2 was extracted with 90% or moreof yield. Next, the verdigris samples wereextracted from the metal fittings installed in therafter of main shrine of Izumo-taisya and theradiocarbon dating of them was performed.
Between the calibrated radiocarbon age and age
when they were made, there was a time lag of
only 4 years. This result shows that the time lag
can be neglected and that verdigris is a suitablesample for radiocarbon dating.

2A07 Feasibility of time-of-flight prompt
gamma-ray analysis of a radionuclide sample
TOH, Y.1,HUANG, M.1, EBIHARA, M.2,
SEGAWA, M.1, KIMURA, A.1, NAKAMURA,
S.1(1 Nucl. Sci. and Eng. Center, JAEA, 2Dep. ofChem., TMU)
The Accurate Neutron-Nucleus Reaction
Measurement Instrument (ANNRI), which islocated at the beamline No. 04 at the Materials
and Life Science Experimental Facility (MLF) of
the Japan Proton Accelerator Research Complex(J-PARC), has been designed and developed forprompt gamma-ray analysis (PGA), nuclear
cross-section data measurement, and nuclear
astrophysics.
We have developed a novel techniquewhich combines PGA with time-of -flighttechnique (TOF-PGA), and attempted to apply
TOF-PGA to the specific detection of radioactive
isotopes in simulated samples of platinum groupmetals in four-group partitioning process. The Ge
detector array, a combination of two cluster-Ge
detectors, seven large coaxial-Ge detectors and
BGO anti-Compton shields surrounding clusterGe and coaxial Ge detectors, is installed at theflight path length of 21.5 m in ANNRI, and isused for measurement of the simulated samples.
Pure metal samples of platinum group provided

2B02 Stream-water organic carbon export

167

from a mountainous forested catchment
TAKEUCHI, E., ATARASHI-ANDOH, M.,
KOARASHI, J., NISHIMURA, S., MUTO, K.,
TSUDUKI,K.,
NAKANISHI,T.,
MATSUNAGA, T.
(Japan Atomic Energy Agency)
Stream-water organic carbon export is an
important pathway for carbon (C) loss frommountainous forest ecosystems and thus
understanding the seasonal changes, mechanisms,
and sources of C export are necessary. We
continuously monitored dissolved organic carbon(DOC) and particulate organic carbon (POC) in asmall river in a mountainous forest in Ibaraki,
Japan, using a monitoring system we developed
previously.
POC samples were collected monthly withcartridge filters installed in the system, whichwere separated by particle size and then analyzed
for C and nitrogen isotopes. DOC concentrations
were determined based on UV absorbancemeasured continuously for passing water in thesystem and a close correlation between DOC
concentration and the UV absorbance.
In general, DOC concentration increased
with increasing water flow in the river. However,the degree of the increase in the concentration
varied depending on the amount of rainfall andthe preceding rainfall pattern. The plot of DOC
concentration vs. water discharge showed two
typical shapes: (1) the DOC concentration
increased with the water discharge, but plateaued
during high water discharge; and (2) the DOC
concentration showed a sharp, linear response to
the water discharge and reached a higher
concentration than in (1). These different
responses were probably caused by thedifferences in rainwater routes to the river.

2B03 Development of uranium age-dating
using 234Th/230Th ratios
OKUBO, A., SHINOHARA, N., MAGARA, M.

168(Japan Atomic Energy Agency)
The uranium age-dating is a nuclear
forensics analysis techniques, by measuring the230
Th / 234U isotope ratio in uranium sample, toestimate the elapsed time from being separated
and purified. We have determined 230Th and 234U
using isotope dilution mass spectrometry method,it has conducted for uranium age-dating. Act toperform the isotope analysis after the addition aknown quantity of the isotope (spike) to thesample, after spiking, analytical sample isassumed to be in the state of isotopic equilibrium.
However, the samples which have complex
speciation of uranium and thorium are analyzed,
may not sufficiently reach to the state of isotopic
equilibrium has been suggested from theexperimental results. In this study, without theaddition of a spike, from the measurement resultsof the uranium isotope ratios and thorium isotope
ratio in the sample, it was investigated a method
for calculating the 230Th / 234U isotope ratio.
The state of radioactive equilibrium
between 238U and 234Th in the sample was utilized
in the 234Th / 230Th method. The 230Th / 234U ratio
was calculated using measured 234Th / 230Th
isotope ratio, 234U / 238U isotope ratio and 234Th /238
U ratio in the radioactive equilibrium.

2B04 Search for supernova signature of 60FeKINOSHITA, N.1, WALLNER, A.2, TIMS, S.2,
FIFIELD, K.2, PAUL, M.3, HONDA, M.4,
YAMAGATA, T.5, MATSUZAKI, H.6(1Shimizu Corp., 2Australian Nat. Univ., 3Hebrew
Univ., 4Univ. Tsukuba, 5Nihon Univ., 6Univ.
Tokyo)
Iron-60 with a half-life of 2.60 My is
produced in the explosive environment with highneutron density such as core collapse supernovae.
The nuclide is hardly produced by nuclear
reactions with cosmic rays in atmosphere. The
Fe-60 atoms were present in the early solar
system but now extinct because of its short life

time. Hence, presence of the live Fe-60 indicatessignature from supernovae which occurred atvicinity of the solar system. Knie (2004) detected
the 60Fe in a manganese crust collected at theeastern Pacific. We attempted to detect the 60Fe
from manganese crusts, nodules, and deep-sea
sediment collected from different location to
verify the previous work.
Ages of the crusts were determined from10
the Be/Be ratio. In measurement of the 60Fe withan AMS, we have achieved detection limit of
4×10–17 for the 60Fe/Fe ratio. We found a 60Fe
peak with the ratio of (2–3)×10–15 from both crustand sediment samples in layers with ages of 1.7–
3.2 Ma. Another peak was observed in layers withage of 6.5–8.7 Ma from one crust sample. The
enhancement in 60Fe is thus observed in 1.7–3.2
Ma from all samples collected from different
location.

and Eu complexes in aqueous solution
corresponds to the Eu / Am selectivity. The
carbonyl oxygen donor as an ester selects Eu(III)ion, whereas, the carbonyl oxygen donor as aketone or an amide selects Am(III) ion. These
results imply that the modification of carbonylgroup enables us to control the Eu / Am
selectivity.

2B05 Ligand strategy for the separation ofminor-actinides and its theoretical evaluation
KANEKO,
M.1,
MIYASHITA,
S.2,
NAKASHIMA, S.1,2(1Grad. Sch. Sci., Hiroshima Univ., 2N-BARD,
Hiroshima Univ.)
We have investigated the bonding state andstability of Eu / Am complexes in order to achieve
the Partitioning and Transmutation strategy ofhigh-level radioactive waste. Our previous workby means of DFT calculation revealed that thecontribution of f-electron to the bonding property
depending on donor atoms determines the Eu /Am selectivity. We aim to introduce the effective
donor group into a TPEN ligand to give a higher
selectivity of Am. The present study evaluates theperformance of a carbonyl donor to Eu / Am
separation with a diglycolamide (DGA) typeligand.
Thecalculation
model,
3+[M(DGA)(H2O)6] , was prepared by themodification of X-ray coordinates of [M(H2O)9]3+.
We assume that the relative stability between Am

169

2B06 Structuraltransformationofcyclouranyl(VI) complex by addition andelimination of proton
NAKAGUCHI, M.1, MORIMOTO, K.1,
YOSHIMURA, T.2(1Graduate School of Science, Osaka Univ.,
2
Radioisotope Research Center, Osaka Univ.)
In the present study, the P3-O and P3-OH
bridged trinuclear uranyl(VI) complexes,(Et3NH)2[(UO2)3O(t-Busap)3](1)
and(Et3NH)[(UO2)3OH(t-Busap)3](2)
were
synthesized by the reactions of UO2(NO3)2・6H2O,
1 equiv. of t-BusapH2 and triethylamine (TEA) in
THF. The complex 1 was obtained by theaddition of 3 equiv. of TEA, and 2 was affordedby 2 equiv. of TEA. The structures of 1 and 2
were determined by single crystal X-ray
diffraction analysis. The U…U distance is av.
3.83 Å for 1 and av. 3.97 Å for 2, respectively.
The U-P3-O distance in 1 (av. 2.23 Å) is much
shorter than that in 2 (av. 2.43 Å). The U-P3-O-U
angle in 1 is 117~119°, suggesting that the P3-O
is sp2 type. On the other hand, the U-P3-O-U
angle in 2 is 110°, which indicates that P3-O in 2
is sp3 type. With the help of DFT calculations, wecharacterized that 1 is P3-O bridged and 2 is P3OH bridged complexes, respectively. The
transformation reactions between 1 and 2 were
investigated.

2B07 Electrode Reaction of Np in a weakly
acidic solution

209

209
Bi(7Li,6n)210Rn
andBi(7Li,p5n)210At
reactions. Irradiation was carried out with 7Li3+
beams of 60 MeV from the JAEA tandem
accelerator at Tokai. Bismuth targets, aluminumbacking and cover sheets were placed at a watercooled Faraday cup. Beam current was controlled
to be approximately 150-200 nA during theirradiation of 2-3 hours. The beam current wascollected by the Faraday cup and was monitored
on-line by using a current integrator module. The
excitation function of 209Bi(7Li,5n)211Rn reaction
is in good agreement with the previously reported
values by Meyer and Lambrecht, and it exhibits
the maximum cross section of 733.8 ± 6.7 mb at
52.4 ± 0.3 MeV. On the other hand, the excitation
function of 209Bi(7Li,p5n)210At reaction, which
was deduced as an independent yield, was lower
than the previously reported one, which wasmeasured as a cumulative yield by Meyer andLambrecht.

KITATSUJI Y., OUCHI K., OTOBE H.
(JAEA)
Electrolytic reactions of Neptunium ions ina weakly acid solution were investigated by using
gold electrode. It was reported previously thatelectrolytic reduction of Neptunium (V) ion
based on mediator reaction with Np(III)/Np(IV)couple was observed in the acidic solution whenbulk electrolysis was carried out at the potential
around -0.2 V versus Ag/AgCl referenceelectrode. The reduction of Np(V), however, was
not observed at the pH higher than 2. This is
attributable to low reaction rate of electron
exchange reaction between Np(V) and Np(III).
Electrode reaction of Np(V) at more negative
potential was investigated by cyclic voltammetry.
The current peak due to reduction of Np(V) was
observed at ca. -0.75 V, and oxidation current wasappeared at +0.5 V. The reactions was determined
to be reduction of Np(V) and oxidation ofdeposited species of reduction product of Np on
the electrode. It was found that stripping current
due to oxidation of deposit was saturated in spiteof longer preelectrolysis time. This phenomenon
is different from uranium.

3A01 Optimisation of the production
parameters of 211At via the 209Bi(7Li, 5n)211Rn
reaction
WASHIYAMA, K.1, MAEDA, E.2, NISHINAKA,
I.3, YOKOYAMA, A.2, HASHIMOTO, K.4,
MAKII, H.3(1Sch. of Health Sci., College of Med., Pharma.
Health Sci., Kanazawa Univ., 2Inst. Sci. Eng.,
Kanazawa Univ., 3ASRC, Japan Atomic Energy
Agency, 4QBSC, Japan Atomic Energy Agency)
Radon-211 (T1/2 = 14.7 h), which is a parentof an alpha-emitter 211At (T1/2 = 7.2h), is a key
isotope for R&D of targeted alpha therapy using
211
At. In order to make a 211Rn with an appropriate
irradiation condition, herein we determined the
209
cross
sectionsofBi(7Li,5n)211Rn,

170

3A02 Production of 211At for alpharadiotherapy via 209Bi(7Li, 5n)211Rn
NISHINAKA,
I.1,
WASHIYAMA,
K.2,
MAEDA,E.2,
YOKOYAMA,
A.2,
HASHIMOTO, K.1, MAKII, H.1(1Japan Atomic Energy Agency, 2Kanazawa
Univ.)A 211Rn/211At generator has been proposed
to supply a radiotracer 211At with a half-life (T1/2= 7.2 h) for medical applications. To establish atechnology of the 211Rn/211At generator, 211Rn(T1/2 = 14.7 h) has to be produced through the209
Bi(7Li, 5n)211Rn reaction without melting
bismuth metal targets due to heat produced by theirradiation of 60 MeV 7Li ion beams. In this work,
we have studied the effects of a He gas coolingsystem of an irradiation chamber constructed forthe production of 211Rn.
Irradiations were carried out at the JAEA
tandem accelerator using the irradiation chamberequipped with the He gas cooling system. The

MIYAZAWA T, 1OYA Y.2(1Sizuoka Univ. Divi. of Tech. Serv., 2Shizuoka
Univ. Divi. Grad. Sch.of Sci.)
The tardigrades belong to a group whichhave a close relationship to an arthropoda and areaquatic animal with a length of 1mm or less.
Tardigrades are with remarkable abilities towithstand harsh physical conditions such as
dehydration or exposure to harmful highly
energetic radiation. An animal in such a conditionis called a tun. But aquatic tardigrades have hightradiation tolerance. We investigated the effects ofindirectactionbyGamma-raysinTardigrades(Milnesium tardigradum). We foundthat aquatic tardigrades withstand 6500Gy
Gamma-rays and be affected byindirectaction.We found temperature effect and dose
effect. H2O2 concentration is affected by survival
rate from 60mM to 80mM.
We will investigate effct of indirect action in
Tardigrades.

results show that the He gas effectively cools thetargets and the cooling efficiency is nearly
independent of the pressure (> 1 kPa) and theflow rate (~20 L/min) of the He gas. Increase intemperature of the bismuth targets was slightly
large compared with that of the aluminum target
owing to the difference of their thermal
conductivity.

3A03 Developments of quantitative imaging
system for alpha-emitting radioisotope 211AtSEGAWA, M.1, NISHINAKA, I. 1, INOUE, T. 1,
HASHIMOTO, K. 1, KURETA, M. 1
(1Japan Atomic Energy Agency)
Radio nuclide therapy using D-particle
emitted from 211At is of current interest because
a-particles have higher LET. Recently, theestablishment of effective technique to generate
211
At is required. Here, quantitative imaging
techniques to analyze the 211At and otherradioactive materials generated at the same time
will be great help for the establishment ofeffective technique. Thus, we has developed
quantitative imaging system adjusted for
relatively low activity a-particles of 211At whichis generated in the research phase. The present
system consist of D-particle scintillator, industrial
camera, macro-lens and control computer. 211At
was generated by 209Bi (7Li, 5n) 211Rn Î 211At
reaction at Japan Atomic Energy Agency. The
consecutive images were obtained with use of211
At as sample. The brightness on 211At images
decreased with increase in the measurement time.
The deduced half-life of 211At from obtained
images agreed with the known value (7.22 h)within 5% error. We confirmed that the present
system could visualize the consecutive images forthe decreasing 211At sample with great accuracy.

3B01 Attempt of Total Synthesis for 14C
labeled C60
AKIYAMA, K., TADAI, T., KUBUKI, S.
(Tokyo Metropolitan Univ.)
Recently, C60 and their derivatives arenoted as an active ingredient owing to highradical scavenging ability and anti-HIV activity.
Considering about the application to thepharmaceuticals and cosmetics, it is necessary to
study the pharmacokinetics of C60. A radioactivetracer method is one of the most effective method
for such research. For the synthesis of 14C labeled
C60 (C60[14C]), the arc discharge method using
carbon electrodes adsorbing 14C labeled
compounds is employed. However, this method
has many problem such as the inconsistency inthe specific radioactivity of the produced C60[14C]
and resulting large amount of radioactive soot asa byproduct. In the recent years, the synthetic
approach to the production of C60 has been

3A04 Effects of indirect action by Gammarays in Tardigrades

171

studied by many organic chemists. If it is possible
to apply these approaches to the production ofC60[14C] some problems mentioned above would
be solved. In this session, we will report theattempt of total synthesis C60[14C].

3B02 Synthesis and Characterization ofPromethium Endohedral Metallofullerenes
MIYAUCHI, S.1, AKIYAMA, K.1, KIKUNAGA,
H.2, KUBUKI, S.1(1Tokyo Metropolitan Univ., 2ELPH, Tohoku
Univ.)
Endohedral metallofullerenes (EMFs),
which are fullerenes including metal atoms, haveattracted interest because of their unique physicaland chemical properties. It is known that various
metal atoms, especially for lanthanides without
Promethium (Pm), are included in the fullerene
cage. Pm is known as an artificial radio element
whose atomic number is smaller than 82. The
chemical properties of Pm are considered to bealmost same as neighboring lanthanides of Nd
and Sm. However, it has been reported that theoxidation state of Sm and Nd in the fullerene cageare +2 and +3, respectively, although the moststable oxidation state is +3 in aqueous solution.
Considering about the chemical properties of Pm,
it is very important to investigate the valence stateof Pm in fullerene cage.
In order to study the properties of Pm@C2n,
we produced Pm by photo nuclear reaction andsynthesized Pm@C2n with DC arc discharge
method. As a result of HPLC analysis of Pm@C2n,
it was found that oxidation state of Pm in thefullerene is +3 from the similarity of HPLC
behavior to other metallofullerenes encapsulating
trivalent lanthanide metal atom.

3B03 Improvement in production yield ofradioactive strontium endohedral fullerene
using nuclear recoil

172

AKIYAMA,
K.1,
MIYASHITA,
Y.1,
HATSUKAWA, Y.2, KUBUKI, S. 1
(1Tokyo Metropolitan Univ., 2JAEA.)
Considering
about
the
radio
pharmaceutical application of metallofullerenes,
the production methods using nuclear recoil
phenomena is very useful because specificradioactivity of products is higher than thatobtained by other methods. Due to theseadvantages, this production method has been
attracted and examined using various nuclear
reactions so far. However, reported production
yields of radioactive metallofullerenes were notenough because of the radiation damages of atargeted fullerene molecule caused by incident
charged particles. One of the promising method
to improve the production yield of radioactive
metallofullerenes is ion implantation using thenuclear recoil induced by nuclear reaction with
fast neutrons. In this study, we will report thesynthesis of 85Sr endohedral fullerene using thenuclear recoil of 86Sr (n, 2n) 85Sr reaction with 14
MeV fast neutron produced by DT reaction.
As a result, the radioactivity of 85Sr
observed in the aniline solutions derived from85
Sr endohedral fullerene was estimated to beabout 6.8% at the best for those before extraction.
Generally, production yield of metallofullerenes
by the standard arc discharge method is about
0.1% or less. Therefore, observed production
yield of 85Sr endohedral fullerene in this study isfound to be extremely efficient compared to thestandard methods.

3B04 Liquid scintillation counting methodwith little liquid organic waste
Furuta, E1, Iwasaki, N.1, Kato, Y.2, Furusawa, T.2,
Yoshimura, T.2(1Ocha Univ., 2Hitachi-Aloka Medical Ltd.)
Low energy beta-ray emitters are generally
measured by a liquid scintillation counter (LSC)
because of its high counting efficiency. However,the LSC method has a demerit for generating
liquid organic wastes after measurement. To
avoid generation of liquid organic wastes, plastic
scintillators (PSs) has been used for measurementof tritium compounds with a conventional LSC.
PSs are a sheet type for nonvolatile compoundand pellets type for volatile compound like HTO.
0.5-mm-thick PS-sheet of BC-400 (SaintGobain) was cut in 13 mm width and 50 mm
height. A PS-pellet of EJ-200 (G-tech Co.) isapprox. 3 mm in a diameter and 3 mm in a length.
Both types of PS were used to check stablecounting efficiency with elapsed time, andlinearity between activities and count rate. For
example, the counting efficiency of 3Hmethionine with the PS-sheets was 43.6 ± 0.3%,
which was same as liquid scintillator use. Also,
the counting efficiency of HTO with the PSpellets was 48.1±0.9%, which was higher thanthat of liquid scintillator. Additionally, both PS
could be reused by rinsing after measurement. So,
there were little wastes. However, these methods
had a limit for applying a large sample volume.

particle shape analysis by electron microscope,and nuclear forensics library) performed in Japan
Atomic Energy Agency are reported. Nuclear
forensics laboratory is one of the components fornuclear forensics regime, where the facilities foranalysis and storage of seized samples areincluded. Quality assurance system for thelaboratory is needed in order to certify thereliability of the analyzed data as evidence.
Japan’s capability on nuclear forensics and therole of radiochemistry are also discussed in the
Symposium from the points of view ofinternational
nuclearsecurity,scientificknowledge necessary to infer the nuclear
attribution by interpretation of the characteristics
of nuclear and radioactive materials, andcultivation of nuclear forensics specialists.

P01 Development of correction methods fortime-of-flight prompt gamma-ray analysis at
ANNRI
HUANG M.1, TOH Y.1, EBIHARA M.2,
KIMURA A.1, NAKAMURA S.1(1Japan Atomic Energy Agency, 2Tokyo
Metropolitan Univ.)
The Accurate Neutron-Nucleus Reaction
measurement Instrument has been available fortime-of-flight (TOF) prompt gamma-ray analysis.
However, the specific relationship between thenumber of detected events and the sample weight
is not entirely clear. In this study, a set of standard
Fe and Ag samples were measured to investigate
the factors which affect the gamma counts and
TOF counts. It is found that live time ofacquisition (τ), data acquisition efficiency in live
time (δ), neutron attenuation (NA) and gammaray attenuation (GA) are the main contributing
factors. An empirical formula is proposed for thecalibration of δ. Simulation models are built for
the evaluations of NA and GA by the PHITS
program. The values of corrected gamma and
TOF counts are simply proportional to the sample

3B05 Nuclear Forensics and Radiochemistry
SHINOHARA, N., KIMURA, Y., OKUBO, A.
(Japan Atomic Energy Agency)
Nuclear forensics is the analysis ofintercepted illicit nuclear or radioactive material
and any associated material to provide evidence
for nuclear attribution by determining origin,history, transit routes and purpose involving suchmaterial. Because the nuclear forensics
methodologies provide hints of the origin of thenuclear materials used in illegal dealings or
nuclear terrorism, it contributes to identify andindict offenders, hence to enhance deterrent effectagainst such terrorism. In the 59th Symposium onRadiochemistry, the results of research anddevelopment of fundamental nuclear forensics
technologies (analysis of isotopic composition,
impurity analysis, age dating of nuclear material,

173

142

Nd(p,J)143Pm and 143Nd(p,n)143Pm reactionsat astrophysically relevant energies: Study forunderstanding isotopic abundance of p-nuclei
144
Sm
HAYASHI, K.1, UENO, S.1, KINOSHITA, N.2,
TAKAHASHI, N.3, YOKOYAMA, A.4(1Grad. School Nat. Sci. Tech., Kanazawa Univ.,
2Inst. Tech., Shimizu Co., 3Grad. School Nat. Sci.,
Osaka Univ., 4Inst. Sci. Eng., Kanazawa Univ.)
The majority of heavy elements which arepresent in the solar system now were synthesized
by neutron capture reaction. However, there is agroup of neutron deficient nuclei, the p-nuclei,
which cannot be created in such reactions. We
have attempted to clarify abundance of the pnuclei with a mass number of 130150 by proton
capture reactions. In the present work, wedetermined cross sections of 142Nd(p,J) and143
Nd(p,n) reactions which are pathway for the
nucleosynthesis of p-nuclei, 144Sm. In addition,
abundance of the 144Sm in stellar environment
was estimated with a network calculation
employing evaluated cross sections.
Targets of 142Nd and 143Nd wereindividually irradiated with low-energy protonbeam. We obtained experimental cross sections of142
Nd(p, J) and 143Nd(p, n) in energies between
4.1 and 7.6 MeV. The experimental cross sectionsof (p, J) reaction showed 3 times greater values atlower energies than theoretical prediction using
TALYS code. On the other hand, the (p, n) crosssections correspond well with the theoreticalprediction.
Abundance of 144Sm created by the proton
capture reactions on pre-existing s-seed nuclei ofneodymium in explosive environment wasestimated with a network calculation. If there is
proton with a density of 1000 g/cm3 at atemperature of 1.5×109 K for example, evaluatedcross sections provide duration of 3 seconds forthe nucleosynthesis.

weight. An accuracy of typically 5% has beenachieved for the corrected result of a standard
sample. It is sufficient for quantitative analysis.

P02 A study on element concentration andacid neutralization capacity of soil at urban
areas
XU, F., SHOZUGAWA, K., MATSUO, M.
(Graduate School of Arts and Sciences, Univ. ofTokyo)In this study, in order to tell the differenceof acid neutralization capacity (ANCc) in urban
areas and the proportion of ANCc in the totalelement concentration in the soil, we took soil
samples from urban areas such as Beijing,
Shanghai and Tokyo. To compare with urban
areas, we also took soil from natural areas such as
Yakushima and Mount Takao. Instrumental
neutron activation analysis (INAA) was used tomeasure the total Ca, Mg, Na and K in soil. We
used inductively coupled plasma atomic emission
spectroscopy (ICP-AES) to measure the ANCc of
soil.
Although plenty of Ca, Mg, Na and K arefound in soil, over 90% exchangeable cations
came from Ca and Mg in all samples while Na
and K made little contribution to the ANCc. The
result shows that Beijing had the biggest ANCc
among 3 cities because a lot of loess moved to
Beijing through dust storm in North China. On
the contrary, soil in Yakushima was made of
granite so that it was lack of both ANCc and thetotal element concentration. According to theorganic compound content in soil, we can see 2
different ways of supplement between urban
areas and natural areas. In urban areas (especially
Beijing), ANCc revive through inorganic salts
primarily. But in natural areas, ANCc revives
through the leaves of deciduous trees.

P03

Cross

sectionmeasurement

of

174

P04 Utilization of BiCl3 as standard for gas
phase chemistry of superheavy elements
Shirai, K. 1, Asai, T. 1, Namba, Y. 1, Aono, R. 1,
Goto, S. 1, Ooe, K. 1, Kudo, H. 2
(1Grad. Sch. Sci. Tech., Niigata Univ., 2Fac. Sci.,
Niigata Univ.)
In the study of super heavy elements, atechnique of an isothermal gas chromatography
has often been used to determine the value of anadsorption enthalpy of volatile compounds. In
many cases, the adsorption enthalpy is derived
from the Monte Carlo simulation which simulates
behaviors of molecules in a column under certain
conditions to reproduce experimental results.
However, the enthalpy has more or lessuncertainty, because it is difficult to estimate
exact
apparatus
constants,
experimental
conditions, etc. In this study, we consider whether
volatile BiCl3 can be utilized as a standard
compound in an isothermal gas chromatography,
because 212Bi, descendant in thorium series, isallowed to use for a tracer. It was found that BiCl3
is volatile and pass through an isothermal column
at a suitable temperature. We will report theresults of macro and tracer-scale experiments anddiscuss more detailed chromatographic behaviorof BiCl3.

extraction behavior of zirconium (Zr) andhafnium (Hf) as lighter homologs of Rf usingdi(2-ethylhexyl)phosphoric acid (HDEHP) as achelate extractant. Radiotracers of 88Zr (T1/2 =83.4 d) and 175Hf (T1/2 = 70 d) were produced byirradiating 89Y and natLu targets with proton ordeuteron beams using the AVF cyclotrons at
Tohoku University and RIKEN. Aqueous
solution of 1 M HClO4 containing the radiotracers
was mixed with an equal volume of HDEHP intoluene, and then the mixture was shaken for 2
hours. After centrifugation, the aliquot of eachphase was subjected to γ-ray spectrometry using
Ge detector. In general, the distribution ratio (D)of Zr is almost the same as or greater than that ofHf, while the order of D value was reversed in
extraction with HDEHP from 1 M HClO4 (DHf >DZr). This shows that extraction study of Rf with
HDEHP is very interesting.

P06 Extraction behaviors of chloride
complexes of Nb and Ta with triisooctyl amine
for chemical experiment of dubnium (Db)
MOTOYAMA, R.1, OOE, K.1, MURAKAMI,
M.1, HABA, H.2, GOTO, S.1, KUDO, H.3(1Grad. Sch. Sci. Tech., Niigata Univ., 2RIKEN
Nishina Center, 3Fac. Sci., Niigata Univ.)
We carried out the solvent extraction ofchloride complexes of niobium (Nb) andtantalum (Ta) with triisooctyl amine for chemical
experiment of dubnium (Db). It has been reported
that the extraction yield of Nb is greater than thatof Ta in this system. Radiotracers, 95gNb and 179Ta,
were produced in the natZr(d,xn) and natHf(d,xn)
reactions, respectively, using the AVF cyclotron
at RIKEN. These radiotracers were chemicallyisolated by an anion-exchange method. The
tracers were preserved in concentrated HCl (stock
solution). Aqueous solution of 8-10 M HClcontaining the tracers was mixed with an equalvolume of TiOA in xylene solution, and the
mixture was shaken for fixed time. The

P05 Solvent extraction behavior of Zr and Hf
with HDEHP for aqueous chemistry of Rf
YAMADA, R.1, OOE, K.1, MURAKAMI, M.1,
HABA, H.2, KOMORI, Y.2, KIKUNAGA, H.3,
GOTO, S.1, KUDO, H.4(1Grad. Sch. Sci. and Tech., Niigata Univ.,
2
RIKEN Nishina Center, 3Research Center Elec.
Photon Sci., Tohoku Univ., 4Fac. Sci., Niigata
Univ.)
Studies on chemical properties ofrutherfordium (Rf) have been carried out mainly
using inorganic ligands such as halide ions, while
few experiments with organic ligands have beenreported. In this study, we investigated solvent

175

radioactivity of each phase was measured by a Ge
detector. The results showed that the distribution
ratio (D) of Nb was approximately 102 times
greater than that of Ta. However, the distribution
ratio of Ta decreased with the lapse of time fromthe preparation of the stock solution. To
investigate a cause of the behavior, we examinedvarious preparation methods of the tracer. It was
found that the distribution ratio and the recovery
rate of Ta exhibit various values depending on the
preparation methods of the tracer.

performed to determine initially added
radioactivity. After shaking and filtration, eachsupernatant was separately collected in a sample
tube, and was subjected to γ-ray spectrometry to
deduce the distribution coefficient (Kd). In theexperiment, the Kd values of 179Ta on the 32 wt%
Aliquat 336 resin were decreased with increasing
HF concentration, while those of 95gNb showed
minimum at 10 M HF. In the presentation, results
on a slope analysis to deduce extracted species
and the comparison with the results of ourprevious liquid-liquid extraction will bepresented.

P07 Solid-liquid extraction of Nb, Ta with
Aliquat 336 resin from hydrofluoric acidsolution for chemical experiment of element
105, Db
SATO, D.1, MURAKAMI, M.1, OOE, K.1,
MOTOYAMA, R.1, HABA, H.2, KOMORI, Y.2,
TOYOSHIMA,
A.3,
MITSUKAI,
A.3,
KIKUNAGA, H.4, GOTO, S.1, KUDO, H.5(1Grad. Sch. Sci. and Tech., Niigata Univ.,
2
Nishina Center for Accelerator Based Science,
RIKEN., 3Japan Atomic Energy Agency.,
4
Research Center for Electron Photon Science,
Tohoku Univ., 5Department of Chemistry, Niigata
Univ.)We have studied the liquid-liquid
extraction behavior of Nb and Ta for the chemical
experiment of Db. Because we are planning to use
ARCA for Db experiment, an Aliquat 336 resin
was prepared and liquid-solid extraction of Nb
and Ta with the prepared resin were carried out.
Radiotracers of 95gNb and 179Ta were produced by
the proton or deuteron bombardments on natZr andnat
Hf metallic foil targets, respectively, using the
AVF cyclotrons at RIKEN and Tohoku University.
These radiotracers were chemically isolated by anion-exchange method. The tracers were dissolved
in HF solutions of various concentrations andthen were mixed with the Aliquat 336 resin in asyringeless filter tube. Control experiments
without the Aliquat 336 resin were also

176

P08 Feasibility study to determine ofamericium activity in plutonium particles byalpha-ray spectrometry
YASUDA, K., SUZUKI, D., KANAZAWA, K.,
MIYAMOTO, Y., ESAKA, F., MAGARA, M.
(JAEA)We are applying a screening technique withalpha-ray spectrometry to the analysis of particles
containing nuclear materials in swipe samples. In
the present study, individual plutonium particles
with known purification dates prepared from astandard reference material (NBS SRM947) were
measured with alpha-ray spectrometry. The
obtained (241Am+238Pu)/(239+240)Pu activity ratios
for the particles with the diameters of more than
1 micrometer were consistent with the reference
values within the uncertainties. These results
indicate that alpha spectrometry can be applied tothe quantitative analysis of 241Am in individual
plutonium particles.

P09 A simple 40K-removal water leachingcombined with AMP method for detection of
low-levels of radiocesium in marine products
YAMASHITA, S.1, INOUE, M.1 , FUJIMOTO,
K.2, NAGAO, S.1, KOFUJI, H.1, HAMAJIMA,
Y.1, YAMAMOTO, M.1

(1Kanazawa Univ., 2Nat. Res. Inst. Fish. Sci.)
The 2011 Fukushima Dai-ichi Nuclear
Power Plant (FDNPP) accident resulted in thewidespread release of large amounts ofradiocesium to sea environments over a wide
region in the eastern Japan. For radioactive
monitorings, 134Cs (half-life: 2.06 y) and 137Cs(half-life: 30.2 y) have been extensively
determined for various marine products overjapan after the FDNPP accident. Within 4 years
from the accidents, concentrations of radiocesium(particularly for shorter-lived 134Cs) in many
marine product samples are gradually decreasing
to “below Detectable level” by conventional γspectrometry except for samples collected fromthe coastal/offshore around Fukushima areas. In
γ-spectrometry of the marine biologicalmonitoring samples non-destructively or after
ashing, a Compton continuum caused by 1461
keV γ-ray of 40K disturbs the determination of
low-levels of radionuclides. In the present study,
to evaluate low-levels of 134Cs and 137Csconcentrations correctly, we developed a simple
40
K removal water leaching treatment and appliedthese procedures to marine products.

operation of domestic RPs and the accident ofFukushima Dai-ichi NPP. 85Kr activity
concentrations of
2.97 Bq/m3 at Chiba and3.95 Bq/m3 at Sapporo were observed in 2006,
which were estimated to be the influence ofdomestic RPs (Tokai and Rokkasho). Several
days after the Fukushima Dai-ichi NPP accident
in 2011, 85Kr activity concentration of 17.7 Bq/m3
was observed at Chiba. It was higher than 10times of the normal level, and it took 3 weeks toreturn to normal.
Atmospheric 85Kr activity concentrations
reached the maximum in 2007. After that, they
showed level or decreasing trend. The yearly
discharges (2006-2012) from RPs in Europe
decreased compared to those before 2006. Fromthese results, a relationship was confirmed
between 85Kr concentration in Japan and theyearly discharges from RPs in Europe. The
relatively high range of 85Kr concentration (1.37- 1.60) in 2014 was estimated to be caused by theincrease of the yearly discharge in 2013.

P11 Continuous observation of atmosphericradionuclides at Kawasaki, JapanSHIOBARA, R. 1, SUZUKI, R. 1, KURIHARA, Y.
2, NAKAMURA, T. 1, KOIKE, Y. 1
(1 Grad. Sch. of Sci. and Tec., Meiji Univ., 2 Org.
Strategic Coordination Res. Intellect. Prop., Meiji
Univ.)
Continuous observations of atmosphericradionuclides were carried out at Kawasaki,
Japan. Atmospheric concentrations of natural(7Be, 208Tl, 210Pb, 212Bi, 212Pb, 214Bi, 214Pb, 226Ra)
and artificial (131I, 134Cs, 137Cs) radionuclides
were observed with aerosol samples collected in
Kawasaki, Japan. The seasonal variations ofseveral radionuclides during the period from
April 2014 to January 2015 were shown in similar
to past variations observed at the present
observation site.
In order to discussatmospheric behavior of radon- and thoron-

P10 Nationwide survey of atmospheric 85Kr
activity concentration in Japan
MATSUBARA, H., NITTA, W., ISOGAI, K.
(Japan Chemical Analysis Center)
Considerable amount of 85Kr is expected tobe discharged into the atmosphere from the
Rokkasho nuclear fuel reprocessing plant (RP)once it begins full operation. Prior to thebeginning of full operation, a nationwide surveyof atmospheric 85Kr has been carried out since2006. Five areas located at different latitudes
were selected for air sampling.
Atmospheric 85Kr activity concentrationsin Japan ranged from 1.31 to 1.60 Bq/m3 (mean±standard deviation(1σ):1.45±0.054 Bq/m3)
except for the temporary increases caused by the177progeny, seasonal variations of radionuclides will
be determined continuously.

of in situ pre-concentration by Powdex resin fromlarge volume of freshwater samples and simple
BaSO4 coprecipitation method was examined.

P12 Development of automatic analysis
system of Strontium-90 in environmental
samples
NOJIMA, T.1, FUJITA, H.1, NAGAOKA, M.1,
OSAWA, T.1, YOKOYAMA, H.1, ONO, H.2(1JAEA, 2Kantogiken Co.Ltd.)An automatic analysis system wasdeveloped to analyze radioactive strontium (90Sr)
radioactivity in environmental samples. The
analysis method was followed to the manualcompiled by the Ministry of Education, Culture,
Sports, Science and Technology, to determine
low level of 90Sr radioactivity concentration inenvironmental samples. In this research, theprocedure of the Sr analysis before milking
procedure of 90Y was automated except for a partof the analysis. The analysis system wasconsisted by the following three apparatuses. Wet
dissolution apparatus was constructed with robot,
hotplate, reagent supply pump and monitor.
Chemical separation apparatus was constructedwith robot, hotplate, pH meter, filter device andreagent supplier. Ion exchange apparatus wasconstructed with ion exchange column, reagent
supplier and monitor. The three systems were
controlled by an original program under the
LabVIEW. Various kinds of ashed environmental
samples were used in performance tests of theautomatic system. These tests were successful
without system trouble. Finally, Sr recoveries
were about 40-70 % to whitebait analyses.

P14 Particle size and chemical form ofradioactive aerosols of 7Be
HIWATASHI, M.1, MURAMATSU, H.2,
KONDO, A.2(1Graduate School of Education, Shinshu
University, 2Department of Chemistry, Faculty of
Education, Shinshu University)
Radioactive materials were released to theenvironment due to the Fukushima Daiichi
Nuclear Power Plant accident in March of 2011.
It is important for us to solve the problems
concerning migration and diffusion processes ofradioactive materials in the environment. So we
tried to estimate the particle size distributions ofatmospheric aerosols attached 7Be and thechemical state of atmospheric aerosol particles asa carrier of radioactive materials. Average
particle size of 7Be was expected to range from0.55 to 0.83 μm. We found that there mainly exist
F-, Cl-, NO3- and SO42- in aerosol particles in air,as far as anions included are concerned. Average
particle size of aerosols including SO42- wasestimated to be in between 0.55 and 0.83 μm. In
addition, it was found that the particle size
distribution of aerosols including SO42- closely
resembles that of 7Be-aerosols. So, we conjecturethat sulfate would be the potential transport
medium for 7Be.

P15 Advance of pretreatment method using
supercritical fluid extraction
NAGAOKA, M.1, FUJITA, H.1(1Japan Atomic Energy Agency)
The radioactivity concentrations in theenvironmental samples are analyzed to confirm
whether radioactivity released from the nuclear
facilities influence on the environment. The

P13 An examination of Ra isotope analysis
from large volume of freshwater samples
TOMITA, J.
(Japan Atomic Energy Agency)
An analytical method of low-level radiumisotopes by J-ray spectrometry with combination

178

pretreatment of radioactive nuclides of alpha andbeta emitters in the environmental samples isperformed with acid regents to decompose
organic matters and extract target nuclides suchas strontium-90, uranium and plutonium.
However, the pretreatment has bad influence on
workers, facilities and environment. Therefore,
we try to develop to the new pretreatment method
using supercritical fluid instead of acid regents.
In this research, we investigate the extraction
yields of stable Sr and 238U into the solvent fromsoil using the supercritical water oxidation(SCWO) reaction on various conditions such asreaction temperature, pressure and duration. The
yields of stable Sr were at most about 60%, while
238
U were less than 1%S. In the future, we try toapply addition of catalyst into the SCWO toimprove the yield of extraction.

Institute)
The radioactive nuclei containing fission
products (FP’s) released from Fukushima Daiichi
Nuclear Power Plant accident were spread as
aerosol particles. It has been reported thataerosols containing radioactive caesium weregenerated as non-sea-salt sulfate aerosols, while
such a selective generation mechanism has notbeen revealed. To understand the generation
mechanism of radioactive aerosols, a generation
system for solid aerosols by heating metal salts
has been developed and attachment behaviors ofFP’s to solid aerosols have been studied in thepresent work.
Powders of sodium chloride or caesium
chloride were heated at various temperatures byelectric furnace and solid aerosols were produced.
Their size distributions were measured by SMPS.
The solid aerosols were injected into a chamberin which spontaneous fission nucleus 248Cm wasinstalled. Radioactive aerosols generated byattaching FP’s were collected by polycarbonate
filters to be subjected to J-ray spectrometry andattachment ratios of FP’s on solid aerosol
particles was estimated.
The attachment ratios do not depend on the
total surface area of aerosol particles clearly but
the chemical species of aerosols. This result
suggests that the chemical interaction plays animportant role in generating radioactive aerosols
by attachment of FP’s on solid aerosol particles.

P16 Influence of the radon for environmental
radioisotopes measurement
KAWASAKI, N.1, YAMANAKA, J.1, TAMARI,
T.1(1Kyusyu
Environmental
Evaluation
Association)For
thestrictmeasurementofenvironmental radioisotopes, it is important toevaluate the background of Rn-220 and Rn-222daughters. The experiments were carried out toestimate Rn-220 and Rn-222-daughters in several
laboratories. Also, the backgrounds of liquid
scintillation counter and Ge detector were
measured under N2 gas purge and, or not. N2 gas
purge was helpful to reduce the interference byradon daughters.

P18 Development of degradation method foranalysis of chlorine-36, iodine-129 andtechnetium-99 in soil samples
Maki, H.1, Keisuke, S.2, Aya, S. 2, Kimikazu, S. 2,
Hiroyuki, M. 3
(1Grad. Sch. Pure Appl. Sci. Univ. of Tsukuba, 2Pure Appl. Sci. Univ. of Tsukuba, The Univ.
Museum, The Univ. of Tokyo)
The safety management for final disposalof spent nuclear fuel will include a search for the

P17 Attachment Behavior of Fission Productsto Aerosol Generated by Heating Metal Salts
NITTA, S.1, TANAKA. T.1, SEKIMOTO, S.2,
TAKAMIYA, K.2, OKI, Y.2, OHTSUKI, T.2(1Kyoto Univ., 2Kyoto Univ. Research Reactor179behavior of 36Cl, 129I and 99Tc in the biosphere.
Behavior of these nuclides in the environment isof great interest because of their high mobility.
The pyrohydrolysis is one of the conventional
decomposition methods for bulk analysis ofchlorine, iodine and technetium in soil samples.
However, this method has some disadvantages. In
this study, we attempt to construct more reliable
and accurate analytical method for 36Cl, 129I and99
Tc in soil samples including degradation
process. In this method, the soil sample is treatedunder subcritical water condition in closed
vessels. Furthermore, we examined anotherdegradation solution of tetramethyl ammoniumhydroxide under the same condition with water
degradation. The isotopic ratios of 129I/127I and36
Cl/Cl in the extracted solution were measured
by AMS. 99Tc concentration was determined bytriple quadrupole ICP-MS. The analytical resultof the degradation method in the case of 127I
showed 31% of that obtained by thepyrohydrolysis method. It was 60% for 129I. As
for the degradation method using TMAH solution,
the result was 81% for 127I and 132% for 129I,
respectively.

P19 The study for measurement of Ra-226
through radon progenies by Ge detector
YAMANAKA, J.1, KAWASAKI, N.1, TAMARI,
T.1
Environmental
Evaluation(1Kyusyu
Association)
Generally, the measurements of Ra-226 insoil by Ge detector are based on the detection of
Pb-214 or Bi-214 that reached equilibrium with
Ra-226. The sample must be sealed up so that Rn
is not lost. The experiment was carried out using
the sample container of different materials toevaluate leakage of the Rn. The result showedthat Rn will leak through the junction of cap
mainly, not through the material itself.

P20 Separation and determination of uranium
and thorium series nuclides in environmental
samples by solid phase extraction method
KURIHARA, Y.1, YOSHITAKE, A.2, FUKUDA,
D.2, FUJII, K.2, NAKAMURA, T.3, KOIKE, Y.3(1Organization for the Strategic Coordination of
Research and Intellectual Properties, Meiji
University, 2Undergraduate school of Scienceand Technology, Meiji University, 3Graduate
school of Science and Technology, Meiji
University,)
A procedure based on a solid phaseextraction method for the separations of U- andTh-series nuclides has been developed. The
procedure was performed with stacked UTEVAResin®, Sr Resin® and DGA Resin® cartridges
from Eichrom Technologies. Sample solution(containing uranium isotopes and thorium-series
nuclides, 8 M HNO3 media) was passed throughthe stacked column at a flow rate of 1-2 mL/min
to extract uranium and thorium isotopes, leadisotopes, and actinium isotopes to UTEVAResin®, Sr Resin®, and DGA Resin®, respectively.
Radium isotopes were separated by the stacked
column, and uranium and thorium isotopes, leadisotopes, and actinium isotopes sequentiallyseparated and purified by UTEVA Resin®, Sr
Resin®, and DGA Resin®, respectively. The
radiochemical recoveries were 95% for uranium
and thorium isotopes, and almost 100% forradium, lead and actinium isotopes.

P21 Study on uranium in coral skeleton Isotopic composition and speciation by
wavelength dispersive XAFS analysesSAKAGUCHI, A.1, MORI, C.2, SASAKI, K.3,
TANIMIZU, M.4, URUGA, T.5, TAKAHASHI,
Y.6(Univ. of Tsukuba, Hiroshima Univ., KanazawaGakuin Univ., Kuwanseigakuin Univ., JASRI,
The Univ. of Tokyo)

180

Age determination of coral sample isgenerally based on the combination of activity
ratios of 234U/238U and 230Th/234U in theskeleton. Validity of the age determination is
confirmed by calculation for initial 234U/238U
activity ratios. However, inconsistency between
calculated initial activity ratios from coral and theratio of modern seawater has been reported. In
this study, chemical speciation of U in coral has
been investigated together with 234U/238U ratio
to serve as an aid to clarify this issue. Based on
the results from XRD analysis and observation ofskeleton structure by electron microscopes, somekinds of coral samples, which have different ages
and species, were analyzed by ICP-MS, EPMA,
MC-ICP-MS, and wavelength dispersive XAFS
after the appropriate pre-treatment for eachanalysis. Uranium concentration in calcite sample
has inverse correlation with Sr content. It might
be due to the transformation of crystal structurefrom aragonite to calcite with diagenesis. The
wavelength dispersive XAFS showed that U
existed as hexavalent form for all coral samples.
The age-corrected values for 234U/238U initialactivity ratio were uniform and showed themodern seawater value regardless of crystal
structures, ages, and species of coral samples.
Thus, the transformation could be occurred
without isotopic fractionation for U. As a resultof this study, it might be suggested that variability
for initial 234U/238U activity ratio is not causedby the coral condition such as species and crystal
structure.

Thin disk-shaped sources of natural radionuclides
were prepared using chemical reagents, KCl
including 40K and Lu2O3 including 176Lu, forgamma-ray spectrometry. Each chemical reagent
was dissolved and a gelatin was added in thesolution. Gelling solutions gelatinized withgelatin were dropped upon filter papers and driedup slowly at low temperatures. Radionuclides
on these sources were distributed uniformly byusing gelatinizer. Several radionuclides inenvironmental samples were determined with
disk-shaped sources prepared using chemical
reagents and gelatinizer. The present method
using commercially available chemical reagentsis applicable to measurements of various
radionuclides concentrated on solid phaseextraction disk out of a radiation controlled area.

P23 The radiocesium measurement of edible
mushrooms and transfer reduction to a fruit
body
MURANOI, T.1, IRISAWA, A.1, KINO, Y.1,
ITABASHI, Y.2, NAKAJIMA, T.2, KORIYAMA,
S.2, KIMURA, E.2, SHIGIHARA, T.2(1Depart. of Chem., Tohoku Univ., 2Kinokkusu
Co.)
The amount of the radiocesium shifted to a
fruit bodies could be reduced from a cultivation
culture medium more compared with zeoliteelement use by using zeolite and potassium
compound as a culture medium additive in
nameko mushroom cultivation .Also we foundthat effect on increased productivity can also be
expected. Therefore we considered whether we
could expect a similar effect in other edible
mushrooms.
We understood that a fruit body could
reduce quantity of the radiocesium which shiftedin comparison with zeolite simple substance use
more by using potassium sulfate together withzeolite in a velvet shank, Hatake champignon, thePleurotus ostreatus like Pholiota nameko.

P22 Preparation of natural radionuclides
source using gelatinizer for gamma-ray
spectrometry
SUZUKI, R.1, KURIHARA, Y.2, Shiobara,R.1,
Saito,T.3, NAKAMURA, T.1, KOIKE, Y.1(1 Grad. Sch. of Sci. and Tec., Meiji Univ., 2 Org.
Strategic Coordination. Res. Intellect. Prop.,
Meiji Univ., 3 Shokei Gakuin Univ.)

181

However, it was admitted the tendency that
became slightly higher a shift coefficient
adversely without being able to confirm the
combination effect with potassium sulfate withother several kinds.

perturbed angular correlation (PAC) technique.
Because the half-life of 19O is as short as 26.9s,
however, it is difficult to introduce the nuclides
into samples by usual chemical treatments.
Therefore, we have developed an online PAC
measurement system coupled to an accelerator,
where recoil 19O nuclei produced by the nuclear
reaction of 18O(d, p)19O can be implanted
kinetically in the sample of interest. For an
operation check of the system, we measured
cascade γ rays emitted from a standard 133Ba
source during beam irradiation. Althoughbackground rate became higher as compared withthat measured without beam irradiation, the halflife of the intermediate state (T1/2=6.27 ns) was
successfully observed. Because the level ofradioactivity of 133Ba is about the same as the
production rate of 19O, it was found that thesystem can be applied to the measurement of19F(←19O) probe. However, we have not beenable to observe the half-life of the second excitedstate of 19F (T1/2 = 89.3 ns). One of the reasons
could be the fact that the recoil 19O nuclei did notcome out of the collimator. Improvement of themeasurement system is now underway.

P24 Radioactive cesium decontamination ofwild mushrooms
YABU, U.1, KINO, Y.2(1Sendai Mushroom Society, 2Department ofChemistry, Tohoku University)
It has been known that mushrooms
accumulate larger amount of radioactive Cs thanagricultural products. Since Fukushima Daiichi
Nuclear Power Plant accident we have collected
over 200 species of wild mushrooms in Miyagi
prefecture that locates on the north of Fukushima
prefecture. Radioactive Cs concentrations in themushrooms were measured with highly pure Ge
detectors and we have reported concentrations ofradioactive Cs in mushrooms. However, thequantities are different from the cookedmushroom. We examined the decontamination ofradioactive Cs from the mushroom. More than
65% of radioactive Cs was removed by boiling,
and nearly 100% was removed by keeping in salt.
K showed the same behavior as radioactive Cs.

P26 Mössbauer spectra and magnetic propertyof diluted Fe doped Perovskite, SrSn1-xFexO3 G
SUZUKI, S.1, KOIKE, Y.1, NOMURA, K.1,2,
KOBAYASHI, Y.3, LI, K.4(1Meiji Univ., 2Tokyo univ. of Science, 3Kyoto
univ., 4Tokyo univ.)
SrSnO3 doped with dilute magnetic ionshas the potential application to spintronicmaterials. Our purpose is the development of new
dilute magnetic at room temperature.
SrSn(1-x)FexO3 (x = 0.005 - 0.15) wereprepared by using a sol-gel method and heating at
400 qC for 2 hours, 850 qC for 2 hours and 1000
qC for 4 hours or 400 qC for 2 hours, 1000 qC for
2 hours.These oxides were investigated by X-ray
diffractionmetry (XRD), a vibrating sample

P25 Improvement of an Online Perturbed
Angular Correlation Measurement System forthe Determination of an Electric Quadrupole
Moment of the Short-Lived 19F(←19O) Probe
FUJISAWA, T.1, SHIMADA, M.1, TAKENAKA,
S.2, MIHARA, M.3, SATO, W.1,2(1Grad. School Nat. Sci. Tech., Kanazawa Univ.,
2Inst. Sci. Eng., Kanazawa Univ., 3Grad. School
Sci., Osaka Univ.)
We have been working on precise
measurement of the quadrupole (Q) moment of
the second excited state of 19F (I = 5/2) fed
through the β- decay of 19O by means of the182

magnetometer
(VSM)
and
Mössbauer
spectrometry. Perovskite oxides with less than 60
nm in diameter were obtained and the lattice
parameters decreased with the increase of Fe
doping rates. Some samples showed theferromagnetism although any oxides were not sostrong. Two doublets and two or four magnetic
sextets were observed in the Mössbauer spectraof SrSnO3 doped with more than 8 % Fe. The two
or four sextets may be attributed to the Fe3+
occupied at the octahedral and tetrahedral sites offerrites
precipitated,
respectively.
Onlyparamagnetic doublets were observed for SrSnO3
doped with less than 2 % Fe although the VSM
results showed a weak ferromagnetism. This may
be due to the induced magnetic defects. Twoparamagnetic doublets may be observed by thedifferent configuration between oxygen vacancy
and substituted Fe ions.

germanium detector.
The characteristic muonic copper X-rays
were successfully detected. Muonic X-ray
spectrum for 84 minutes muon irradiation gave aclear μCu (4-3) X-ray peak with 7% statistic error.
A good S/N ratio as 5 in μCu (4-3) peak was
obtained. In RCNP-MuSIC, additional shield is
now constructing to use a stronger incident protonbeam, and various application studies using
intense muon beam will soon be possible.

P27 Measurements of characteristic muonic
X-rays using RCNP-MuSIC muon source
INAGAKI, M.1, NINOMIYA, K.1, YOSHIDA,
G.1,
SATO,
A.1,
KAWASHIMA,
Y.2,
KOHNO,Y.1,
MATSUMOTO,
Y.1,
NAKAZAWA,
Y.1,
TAKAHISA,
K.2,
SHIMOMURA, K.3, HIGEMOTO, W.4,
SHINOHARA, A.1(1Grad. Sch. Sci., Osaka Univ., 2RCNP, Osaka
Univ., 3KEK, 4JAEA)
MuSIC, the intense DC muon-beam facility,
have been constructed at the Research Center for
Nuclear Physics (RCNP) in Osaka University,and a beam commissioning have been performed
for starting of research use. We performed
preliminary experiments of characteristic muonic
X-ray measurement at RCNP-MuSIC.
The experiment was performed at MuSICM1 beam line. The copper plate was irradiated by
the muon beam decelerated by the aluminum
plate, and characteristic muonic X-ray emitted
from muonic atom was measured by high purity

183

P28 Compositional Study of Iron-Containing
Mineral in an Ordinary Chondrite Saratov by
Mössbauer Spectroscopy
NAKAGAWA, M.1, KANO, Y.1 , EBIHARA,
M.3 , SATO, W.1,2(1Grad. School Nat. Sci. Tech., Kanazawa Univ.,
2Inst. Sci. Eng., Kanazawa Univ.,
3
Grad. School Sci. Eng., Tokyo Metropolitan
Univ.)
Chondrites are the most primary source ofplanetary bodies; compositional studies onmineral containing iron, the main component
element of chondrite, are therefore very importantfor obtaining information on the formation
process of our solar system. In this work, we
carried out a Mössbauer spectroscopic study onan ordinary chondrite Saratov (L4). A Mössbauer
spectrum for Saratov has already been shown by
Oshtrakh et al; however, information aboutmagnetism of each mineral is insufficient because
the measurement was performed only at room
temperature. We thus introduced a lowtemperature Mössbauer spectrometer andobtained a spectrum for Saratov at 10 K. The
spectrum consists only of components related toprimary minerals of chondrite (olivine, pyroxene,
FeS, and Fe-Ni), and even at this low temperature,
new sextet arising from phase transition ofsuperparamagnetic doublet expected by Oshtrakh
et al. was not detected, revealing that Fe3+ ionsdo not to exist in our sample. This observationsuggests that the mineral containing Fe3+ wasoxidized by weathering on the earth after its
falling on the ground.

reduction current of U(V). In this study, weinvestigated the relationship between reduction
process and formation of aggregates bymeasuring electrochemical quartz crystal
microbalance(EQCM).
When
EQCM
measurements of the reduction of U(V) to U(IV)in weakly acid solution were performed, thefrequency was changed negatively. This indicatesthat aggregates of U(IV) were formed on theelectrode. We consider that aggregates form in thethree steps from the deposition rate; the induction
step (~start deposition), early stage aggregation
step (deposition amount ~4 nmol) and secondary
stage aggregation step (deposition amount >4nmol). The pH dependence of the reduction anddeposition rate was investigated. The U(IV)aggregates formed at more than pH 3.1. When pH
was higher, the induction time was fast, andaggregation rates at early and secondary stage
were high. This suggests that a U hydroxide
relates to the formation of aggregates.

P29 Characterization of the stable isomers for
U(IV) and U(V) complexes with Schiff-baseligands
YOSHIMURA, T.1, MORIMOTO, K.2(1Radioisotope Research Center, Osaka Univ.,
2
Graduate School of Science, Osaka Univ.)
For characterization of stable isomers foreight coordinate U(IV) and U(V) with Schiffbase ligands, DFT calculations were performed tosquare-antiprismatic U(IV) and U(V) complexes
and to dodecahedral U(IV) and U(V) complexes.
In the geometrically optimized structures of thecomplexes, the U-O and U-N bond distanceswere similar to those determined by single crystal
X-ray diffraction analysis. The total bonding
energies for the U(IV) isomers indicate that themore stable isomer is the complex having asquare-antiprismatic structure. The squareantiprim U(IV) is 7~8 kJ/mol more stablecompared with the dodecahedral structures. In thecase of U(V), the total bonding energies of theisomers revealed that the dodecahedral structure
is more stable than the square-antiprismatic
structure. The results by DFT calculations areagreed well with the results obtained fromexperiments.

P31 Selective extraction of cesium andstrontium〜solvent extraction III by risk-free solvent〜
NAGAI, M., SHIRASAKI, K., SAKAMOTO, K.,
YAMAMURA, T.
(Laboratory of Alpha-Ray Emitters IMR Tohoku
Univ.)High level nuclear waste includes 137Cs and90
Sr, both are one of the most important longlived fission products. Recently solvent
extraction has been studied in order to remove
these nuclides from the high level nuclear waste.
The solvent extractions are one of the most useful
separation methods of metal ions. Using 1,2dichloroethane, 1-octanol or chloroform as adiluent and crown ethers can functions as
extractants of cesium and strontium from acidsolutions[1][2]. The diluents have risks of fires,
explosions and environmental soundness. In ourprevious works, the solvent extraction of uranium

P30 Investigation of the process for aggregate
formation with the reduction of uranium
OUCHI, K.1, OTOBE, H.1, KITATSUJI, Y.1(1Japan Atomic Energy Agency)
It is important to understand the behaviorof actinide ion in nature environment. In previous
study, it was found that aggregates of U(IV)formed in reduction process of U(V) enhanced
the rate of the disproportionation of U(V) and the184

from nitric acid solution was conducted by HFC43-10mee（DuPont; Vertrel XF）-TBP system.
The diluents show excellence in thenoninflammability, the low toxicity, and chemical
stability.
In this study, we investigated the use ofazeotrope of HFC-43-10mee as a diluent. We will
present the results alkali metals and alkaline earth
metals from acid solution by dicyclohexano-18crown-6-ether as an extractant in this diluent.

and TG/DTA. The extraction experiments oflanthanide series elements except for promethium
were performed with changing the nitric acidconcentration, the ligand concentration and theorganic phase compositions. The concentrationsof lanthanides in aqueous phases were measured
by ICP-MS. UV-Vis spectroscopic titrations for tPhen with Eu3+ or H+ in acetonitrile solution was
also performed. Other details for substituent
effect for three ligands will be presented in ourposter.

[1] R. A. Sachleben, et al., Sep. Sci. Technol.,32(1997)275.
[2] K. K. Gupta, et al., Sol. Extr. Ion Exch.,
21(2003)53.

P33 Structure and stability of EDTMP and
DOTMP complex with Th(IV) for nuclear
medicine
YAMAMURA, T.1, SHIRASAKI, K.1, FURUYA,
M.1, KITABAYASHI, K.1, WASHIYAMA, K.2,
AMANO, R.2, OHTSUKI, K.3(1Tohoku Univ., 2Kanazawa Univ., 3Kyoto Univ.)
In our experiments where Th-227 labeled
EDTMP was administered to mice, the selective
accumulation of daughter nuclides Ra-223 andRb-221 to bones, and the clearance from nontarget organs have been found. On the basis of
this result showing that Th-EDTMP is collectedby bones at high ratio, we are studying thecomplexes of EDTMP and DOTMP with alpharay emitting nuclides.
In this study the stability constants of thecomplexes of EDTMP and DOTMP with Th(IV)was determined. In the titration experiments
using a series of metal ions, DOTMP shows larger
l logKML values for d transition metals, because
the number of nitrogen donor atoms are larger by
two in DOTMP than EDTMP. In contrast to dtransition metals, Th shows similar behaviors to
Ca, rather than to d transition metals, in values of
logKML and logKMHL. This is indicative that thecoordination by nitrogen donor atoms is rather
weak.
Also, the bond lengths between Th anddonor atoms were elucidate by crystallography. In

P32 Synthesisofmono-triazinylphenanthroline derivatives for MA/Ln
partitioning and the performance evaluationin lanthanide series elements.
KAMEZAWA, A.1, SUZUKI, S.2, KOBAYASHI,
T.2, SAKAGUCHI, A.3, SUEKI, K.3(1Grad. School of Pure and Appl. Sci., Univ.
Tsukuba., 2JAEA., 3Faculty of Pure and Applied
Science, Univ. Tsukuba.)
It is one of the essential issue to separate
Minor Actinides (MA) and lanthanides from highlevel radioactive waste from the aspect ofPartition & Separation (P&T). However, thepractical/appropriate methods have not been
constructed. In this study, we focused on solvent
extraction using 2-(1,2,4-triazine-3-yl) 1,10phenanthroline (t-Phen) which may containtridentate coordination site. The performance
evaluation such ligands are hardly investigated.
T-Phenligands,
havingdifferent
substituents (methyl group, ethyl group, phenylgroup) at 5,6-position of each triazine ring, weresynthesized
from
1,10-phenanthroline-2carboxamidehydrazone
with
α-diketone
following known procedures. All the ligands
were obtained as hydrates identified by 1HNMR

185

the DOTMP complex, the coordination is muchstronger than in the EDTMP complexes. However,
Th-N bond length is the longest among the known
complexes.

P34 Production of 67Cu for cancer therapy
with accelerator neutrons by deuterons
HASHIMOTO, K.1, KAWABATA, M.2, SAEKI,
H.2, SATO, S.2, TSUKADA, K.1, HATSUKAWA,
Y.1, NAGAI, Y.1, WATANABE, S.1, ISHIOKA, N.
S.1(1 Japan Atomic Energy Agency, 2 Chiyoda
Technol Corporation)
Copper-67 is an attractive radionuclide forcancer therapy, because of emissions of medium
energy beta particle (a mean energy of 141 keV)and gamma rays (91, 93, 185 keV) suitable for
imaging, and its appropriate half-life (62 hours).
However, the use of 67Cu in clinical research has
been limited due to the difficulty in obtaining asufficient amount of 67Cu. In this study, we haveinvestigated the production of 67Cu by the68
Zn(n,x)67Cu reaction (x=n’p, d) using fastneutrons from natC(d,n) or natBe(d,n) reaction. The
highly purified 67Cu was obtained from a
considerable amount (33 g) of ZnO sample bytwo columns (chelate resin chelex-100 and anion
exchange resin AG1-X8). By using the obtained67
Cu solution, the labelling of DOTA and TETA
which are useful bifunctional ligands for thelabelling monoclonal antibodies was succeededin more than 97% yield. In addition, we
successfully developed a recycling process of theused 68ZnO sample by precipitating 68Zn(OH)2
from the separated Zn fraction. It was confirmedthat the recycled sample did not include the extra
impurities inhibiting the labelling reaction of
DOTA or TETA.

P35 Recovery and purification of 99mTc
isolated from 99MoO3 using a thermal

186

separation technique
KAWABATA, M.1, HASHIMOTO, K.2,
MOTOISHI, S.1, SAEKI, H.1, SHIINA, T.1,
OHTA, A.1,TAKEUCHI, N.1, NAGAI, Y.2,
(1Chiyoda Technol Corporation, 2Japan Atomic
Energy Agency)
99m
Tc is a daughter nuclide of 99Mo and is
the most widely used radionuclide in nuclear
medicine diagnosis. The thermo-separation of99m
Tc from 99Mo produced using accelerator
neutrons has been found to be a promising
method to obtain a high purity 99mTc from 99Mo
offering a constant high efficiency. Irradiated100
MoO3 samples are heated in a tube furnace
where 99mTc alone is thermally separated from thesamples. Post-separation procedures involved
washing the deposited 99mTc from the quartz tube
wall in the low temperature region. The collected99m
Tc was loaded onto an alumina column whichis then eluted with a small quantity of saline
solution to obtain 99mTc as TcO4-. This waspreviously performed with 0.1 mM NaOH
solution to allow 99mTc adsorption onto analumina column (SepPak Alumina N Plus Light,
Waters), however the washing efficiency was
erratic (50-90%) affecting the total yield. In thisstudy the 0.1 mM concentration of NaOH wassubstituted by 0.1-0.05 M to increase thesolubility of 99mTc in the solution, which was thenneutralized by a cation-exchange column(Dionex OnGuard II-H, Thermo Fisher Scientific,Inc.) coupled with an alumina column for 99mTc
adsorption. As a result, a high 99mTc washingefficiency (> 95%) was consistently obtained
leading to a high total 99mTc yield using thethermo-separation system.

P36 Extraction experiment in a closed systemusing syringes for a simulation of 211Rn/211At
generator
MURAKAMI, K. 1, OOE, S1., TANIGUCHI, T.1,
HASHIMOTO, K.2, MAKII, H.2, NISHINAKA,

I.2,WASHIYAMA, K.1, YOKOYAMA, A.1(1Kanazawa Univ., 2 JAEA)The 211At isotope (T1/2= 7.2 h), an α emitter,has attracted attention as a nuclear medicine forthe treatment of cancer. Because α-particles are
expected to make higher therapeutic effect thanβ-particles due to high linear energy transfer.
There is also a feature that can be treated without
damaging the normal cells around a tumor. The
half-life of 211At is, however, not long enough to
use in areas remote from the production facilities.
We produced 211Rn (T1/2= 14.6 h) in the reactionof 209Bi(7Li,5n)211Rn using the JAEA-Tokai
tandem accelerator to study the establishment ofa generator technology that enables the remotelocation use by milking an 211At isotope as adaughter nuclide of the generator. In this study,
we devised a generator of a complete closed
system by using two syringes, and performed atrial for milking of 211At from 211Rn by solvent
extraction.

We have produced the following RI for
nuclear medicine to date using the AVF cyclotron
and ring cyclotron at RCNP. The 52Fe (T1 / 2 = 8.28h), 62Zn (T1 / 2 = 9.26 h), 65Zn (T1 / 2 = 244.1 d),
99
Mo (T1 / 2 = 65.94 h), 99mTc (T1 / 2 = 6.01 h), 124I
(T1 / 2 = 4.18 d), 191Pt (T1 / 2 = 2.91 d), 210At (T1 / 2= 8.14 h), and 211At (T1 / 2 = 7.21 h) were prepared.

P38 Production of medical radioisotope 90Y at
a zirconium target irradiated by fast neutrons
in the 9Be(p,n) reaction
TAKEDA, S.1,2, TSUKADA, K.2, SATO, T.K.2,
ASAI, M.2, NAGAI, Y.2, SAKAMA, M.3,
MATSUMOTO, E.1(1Tokushima Univ., 2JAEA, 3Depart. Radiological
Science, HBS, Tokushima Univ.)
Today in nuclear medicine, many kinds ofradioisotopes play an important role inradiological diagnosis and therapy of a specificdisease such a cancer. In particular, for yttrium90 it is well-known that the90Y-labeled
radiopharmaceutical such as ibritumomab
tiuxetan (ZEVALIN®) are widely used for thetreatment of non-Hodgkin’s lymphoma (NHL) in
the world. We have ever investigated theexcitation function of90mY associated with the
production of90Y on a zirconium target by a fastneutron beam, and also estimated the optimized
production condition of the90mY nuclides withrespect to primary proton-induced beam energies,
target condition and productions of by-products(89Zr,87mSr and so on). Each of fast neutron beams
was generated along with 15 to 30 MeV protoninduced reactions on a beryllium target using a
cyclotron accelerator such a medical PET
cyclotron currently in use. The purpose of thiswork is to reproduce distributions relative to fastneutron fluxes around the target position alongwith each of the primary proton-induced energies
using the Monte Carlo simulation code of PHITS,
and also to estimate the productions of90mY andthose by- products on the assumptions of various

P37 Production of Radioisotopes for Nuclear
Medicine Diagnosis and Therapy at RCNP
Osaka University
TAKAHASHI, N., HAYASHI, Y., KANDA, H.,
NAKAI, K., SHINOHARA, A., FUKUDA, M.,
HATANAKA, K., IKEDA, H., HATAZAWA, J.
(1Grad. Sch. Sci., Osaka Univ., 2RCNP Osaka
Univ., 3Grad. Sch. Med., Osaka Univ.)
Today, the use of different RI with thediversification of the nuclear medicine
diagnostics and therapy have been made. Almost
all of the 99mTc that are used in SPECT rely on
imports, but has been studied much be produced
using domestic accelerators. Also in the PET
diagnostic 18F but is being used to keep a numberof facilities at home and abroad, the use of β +emitting nuclides of long life has been demanded.
Furthermore lest therapy with α-ray has also beenstudied, 211At has been taken up as its promising
nuclide.

187

Meiji University, 2Organization for the Strategic
Coordination of Research and Intellectual
Properties, Meiji University)
The leaching behavior of Ra isotope frompitchblende, radioactive mineral, was observed
along pH of HCl aqueous solutions in contact.
The activity ratios of 223Ra/226Ra in the leachates
were observed to be larger than that in the mineraland tended to increase with an increase in pH of
the HCl aqueous solutions. This tendency
indicates that 223Ra is preferentially leached ascompared with 226Ra. Radium-226 and 223Ra
are formed through three alpha decays from theparent nuclides which 238U and 235U, respectively.
The extent of damage around a nuclide isassumed to be proportional to the total alphaenergy released in the formation of the nuclide.
The summation of all alpha energy released intransformations from 235U to 223Ra is larger thanthat in the transformations from 238U to 226Ra.
Therefore, the difference in leaching efficiency of223
Ra and 226Ra was estimated to be due to thedifference in total alpha energy released in theformation of the nuclide.

source and tally conditions based on ourdeveloped production reaction system using the
DCHAIN-SP2014 program included into the
PHITS code package.

P39 Lateral distribution and seasonalvariation of 228Th/228Ra ratio in surface
seawaters of the East China Sea and the Sea ofJapan
SHIROTANI, Y.1, INOUE, M. 1, NAGAO, S. 1,
YAMAMOTO, M. 1, HAMAJIMA, Y. 1,
FURUSAWA, Y. 1, KOFUJI, H. 1, HONDA, N.2,
MORIMOTO,
A.3,
TAKIKAWA,
T.4,
FUJIMOTO,K.2, HAYAKAWA, K. 1
(1Kanazawa Univ., 2Fish. Res. Agency. 3Ehime
Univ., 4Nat. Fish. Univ.)
A total of ~100 surface seawater samples
were collected with in the Sea of Japan and theEast China Sea (ECS) in 2008-2014, and lateraland seasonal variations of 228Th (t1/2 = 19.1y)/228Ra (t1/2 = 5.75 y) ratio were examined by
low-background gamma-spectrometry. In earlysummer, within the ECS, the 228Th/228Ra ratio of
the continental shelf water-rich surface waters
was markedly lower relative to the Kuroshio
water, being due to preferentially removal of228
Th from the surface by a high flux of biogenic
particles. The 228Th/228Ra ratio at surface in the
Sea of Japan exhibited small variation with therange of the eastern ECS. Combining with theseasonal variation of 228Th/228Ra ratio and shortlived 234Th (t1/2 = 24 d), we discuss the scavenging
mechanisms and behaviors of reactive
components at surface within the Sea of Japan.

P42 Cross section measurement of 80 MeV
neutron induced reaction for meteorite
constituent elements
NINOMIYA, K.1, NANBU, A.2, SHIGEKAWA,
Y.1, TAKAHASHI, N.1, SHINOHARA, A.1,
SEKIMOTO, S.3, YASHIMA, H.3, SHIMA, T.4,
HAGIWARA, M.5, IWAMOTO, Y.6, SHIBATA,
S.7, CAFFEE, M. W.8, NISHIIZUMI, K.9(1Grad. Sch. Sci., Osaka Univ., 2Sch. Sci., Osaka
Univ., 3Kyoto Univ. Res. Reactor Inst., 5RCNP,
Osaka Univ., 4KEK, 5JAEA, 6RIKEN, 7Purdue
Univ., 8Univ. California Berkeley)
The determination of cross-sections byneutron-induced nuclear reaction is very
important in the view point of space and planetarysciences to investigate the history of cosmic ray
exposure. These data are also required for

P40 Leaching of uranium and thorium series
nuclides from pitchblende
KOMATSUBARA, K.1, KURIHARA, Y.2,
SHIOBARA, R.1, NAKAMURA, T.1, KOIKE,
Y.1(1Graduate school of Science and Technology,188estimation of residual radioactivities inaccelerator facilities. However, cross section
measurements in the energy region have scarcely
been limited due to difficulty in obtaining highenergy monoenergetic neutrons. Our group has
developed a method to extract the component ofhigh energy monoenergetic neutrons at the
Research Center for Nuclear Physics (RCNP),
Osaka University. This method is based on two
neutron irradiation experiments produced by Li(p, n) reaction with two different angles for theaxis of the primary proton beam to correct thecontribution of the low energy neutron reaction.
In this study, high-energy monoenergetic
neutron-induced reactions with 80 MeV havebeen studied for meteorite constituent elements,
and cross sections of short-lived radionuclides
were determined by gamma-ray spectrometry.

P43 Measurement of radioactive Cs in monkey
cartilages collected in Minamisoma city
NISHIYAMA,J1.,KOARAI,K1.,KINO,Y1.,SHIMIZU,Y2.,TAKAHASHI,A2.,SUZUKI,T2,3.,CHIB
A,M2.,OSAKA,K2,3.,SASAKI,K2.,FUKUDA,T4.,
ISOGAI,E4.,OKA,T1,6.,SEKINE,T1,6.,FUKUMO
TO,M6.,SHINODA,H2(1Department of Chemistry, Tohoku University,
2
Graduate School of Dentistry, Tohoku University,
3
International Research Institute of Disaster
Science, Tohoku University, 4Graduate School of
Agricultural Science, Tohoku University,
5
Institute for Excellence in Higher Education,
Tohoku University, 6Institute of Development,
Aging and Cancer, Tohoku University, Japan)
We determined Cs-137 concentrations ofcartilages and bones in monkeys that inhabited in
Minamisoma City. The concentrations ofcartilages and bones were 6631±14 Bq/kg and3725±14.46 Bq/kg in young monkey and415.4±5.16 Bq/kg and 178.4±1.94 Bq/kg in childmonkey. The concentrations of cartilages werehigher than that of bones.
Stable Cs concentration of cartilages andbones were also determined to be 769±37 ppb and373±19 ppb in young monkey and 47.3±1.4 ppb
and 29.3±1.0 ppb in child monkey. The stable Csconcentrations of cartilages were higher than thatof bones the same as the Cs-137 concentrations.
Specific activities of Cs-137 of cartilages andbones were 9.45±0.24 Bq/μg Cs and 8.67±0.36
Bq/μg Cs in young monkey and 10.1±0.3 Bq/μg
Cs and 6.70±0.24 Bq/μg Cs in child monkey.
The specific activities of Cs-137 wereconstant between the cartilages and bones. The
result showed that the differences of the Cs-137
concentrations between the cartilages and bones
don’t depend on the Cs-137 pollution at theresided area of monkeys. The cartilages containedlarge amount of Cs-137 because the cartilages
contained more stable Cs than the bones and Cs137 incorporated into cartilages with stable Cs.

P42 Seasonal variation of radioactive cesium
concentration in Fukushima City
NINOMIYA, K.1, ZHANG, Z.1, MATSUNAGA,
S.1, SUZUKI, A.1, FUJITA, M.2, YAMAGUCHI,
Y.3, WATANABE, A.4, TSURUTA, H.5, KITA,
K.6, SHINOHARA, A.1(1Grad. Sch. Sci., Osaka Univ., 2Sch. Sci., Osaka
Univ., 3RI Res. Center, Osaka Univ., 3Fukushima
Univ., 4Univ. Tokyo, 3Ibaraki Univ.,)
A large amount of radioactive nuclides
were released in the environment by the accident
at the Fukushima Daiichi Nuclear Power Plants(FDNPP) in March 2011. We have beencollecting air-dust on a filter using high volume
air sampler at Fukushima city (Fukushima Pref.),
Marumori town (Miyagi Pref.) and Hitachi city
(Ibaraki Pref.) just after the accident. We
identified the radioactivities of 134Cs and 137Cs in
the filters using HPGe detector. In this paper, time
variation among three sampling point and air-dust
size distribution of radioactive concentrations
will be discussed.

189half-life radionuclide, 137Cs was transported
through the atmosphere mainly as the aerosol
form and deposited to the forests in Fukushima
prefecture. For evaluation of behavior of 137Cs invegetation system, fundamental data fordeposition and uptake process of sulfate aerosol
was desired. In this study, we developed aerosol
generation system for simulating the dry
deposition and the foliar uptake behaviors ofaerosol in the different chemical constitutions. In
this system, the method of aerosol generation
based on the spray drying. Solution was send to anozzle by a syringe pump and spraying with ahigh speed air flow. The sprayed mist was
generated in a chamber in the relatively hightemperature. The solution in the mist was dried
quickly, and micro size solid aerosols weregenerated. The experimental condition, such as
the size of chamber, chamber temperature,solution flow rate, air flow rate and so on, were
optimized. In the presentation, we will discuss theperformance of the aerosol generation system.

P44 Evaluation of Influence of the Fukushima
Dai-ichi Nuclear Accident on EnvironmentalJ-ray Dose Rate in Miyagi Prefecture
ISHIKAWA, Y.1, ARAI, Y. 2, KIMURA, A. 1,
SATO, K. 1, KAYANO, M. 1, MINATO, S. 3
(1Miyagi Pref. Environ. Rad. Monitoring Center,2
Miyagi Pref. Nucl. Safety Div., 3Radiation Earth
Sci. Lab)In this paper, evaluation of radiocesium(Cs-134+137)-contribution in air-absorbed γ-ray
dose rate observed in Miyagi Pref., adjacent toFukushima Pref., was discussed in order toestimate the influence of the Fukushima Dai-ichi
Nuclear Accident. Environmental γ-ray spectra
were measured in Miyagi Pref. by using a 3”φ×3”
NaI(Tl) detector and the data were processed bya G(E)-function method and a 49×49 response
matrix (RM)-method, which was speciallydeveloped to evaluate radiocesium dose
contribution.
Inevaluating
radiocesium
contribution, the RM-method needs only onetime spectrum measurement, though the G(E)function method needs natural background doserate data before contaminated by radiocesiums
from the Fukushima Dai-ichi Nuclear Accident.
In our study, about 20-100 nGy/h in total 40-140
nGy/h were evaluated as radiocesium dose
contribution. Total and radiocesium dose rates
obtained by the RM-method agreed with those of
the G(E)-function method, within 5% and 15%,
respectively.

P46 Vertical distribution of radioactive
cesium in the sediments of Tokyo-bay andChiba’s urban river released by the
Fukushima Dai-ichi nuclear power plant
accident
SOEMORI, A., SHOZUGAWA, K., MATSUO,
M.
(Univ. of Tokyo)
To make clear the behaviors of radioactive
cesium in hydrosphere released by the FDNPP
accident, we measured its vertical distribution in
the two groups of sediments, in Tokyo-bay
located off Makuhari and in Chiba’s urban river
including Hanami-river and Shinkawa. For
analysis in Tokyo-bay, two types of sediments (anartificial deeper site and a natural shallower site)were compared from February ’13 to August ’13.
Radioactive Cs in both sediments had gone
deeper and deeper, reaching 40 cm layer in thisP45 Development of the aerosol generation
system for simulating the dry deposition
behavior of radioaerosol emitted by theaccident of FDNPPZHANG.Z, NINOMIYA.K, SHINOHARA.A(Graduate School of Science, Osaka University)
A large amount of radioactivity wasdischarged by the accident of FDNPP. The long190

area, while more than 90 % of Cs in soil isrecognized to stay in the upper 5 cm layer. In
addition, the inventory of Cs had increased. The
phenomenon was especially observed moreclearly at the deeper site than at the shallower site.
It is supposed that the deeper site in Tokyo-bay
have the feature of collecting Cs. On the other
hand, about the urban river, Cs had also gone todeeper sediments in some areas, reaching about
30 cm to 50 cm layers. Moreover, theconcentration of Cs in each layer of the river’s
sediments is clearly higher than Tokyo-bay’s. It issuggested that urban rivers behave not only as Cscarrier to sea but also as Cs-storage in themselves.

P48 Dispersion of radioactive cesium released
from the Fukushima Dai-ichi NPP in coastal
area off Fukushima Prefecture
BABA, H.1, NAGAO, S.2, MIYATA, Y.2, INOUE,
M.2, TOMIHARA, S.3, TANAKA, K.4,
OTOSAKA, S.5(1Graduate School of Natural Sci. Technol.,Kanazawa Univ., 2Institute of Nature andEnvironmental Technology, Kanazawa Univ.,
3
Fukushima Marine Science Museum Foundation,
4
Atmosphere and Ocean Research Institute, theUniv. of Tokyo, 5Japan Atomic Energy Agency)
Nuclear accident occurred on 11 March2011 from stopping the cooling system and power
supply at the Fukushima Dai-ichi Nuclear Power
Plant (NPP) by the Great East Japan Earthquake
and tsunami. Radioactive cesium (134Cs, 137Cs)
was released from the NPP into the environment.
The dispersion of radiocesium added to the ocean
is essential to understand the impact ofradiocesium to the coastal ocean off the
Fukuhisma Prefecture. Therefore we determined
the spatial and temporal variations of radiocesiumin the Fukushima coastal areas and evaluated thehorizontal and vertical variations by measuring
the concentration of radioactive cesium in the
periodic sampling of coastal seawater at Iwaki off
the coast by the Fukushima Marine Science
Museum Foundation, and the seawater that wascollected by Tansei-Maru research expeditions inAugust 2012 (KT-22-12) and in January 2013
(KT-13-01).134Cs concentration of the KT-13-01
samples showed an approximately 200-times
higher value at the maximum (in the case ofcomparing the C03 and J10) than those of the KT12-22 samples. The results of periodic sampling
will be also used for discussing the situation ofdiffusion behavior of radiocesium.

P47 Rapid Determination Method for 90Sr in
Seawater from 90Y Measurement Through
Yttrium Phosphate Coprecipitation and
Purification with DGA Resin
SAKAI, H.1, UESUGI, M.2, YOKOYAMA, A.3(1Grad. School Nat. Sci. Tech., Kanazawa Univ.,
2Adv. Sci. Res. Cent., Kanazawa Univ., 3Inst. Sci.
Eng., Kanazawa Univ.)
Strontium 90 is one of the nuclides thathave been released to the environment by the
Fukushima Daiichi nuclear power plant accident.
The radioisotope has been leaking to theunderground and released into the ocean withcontaminated water. The rapid measurement of90
Sr in seawater is necessary for environmental
monitoring in Fukushima. It requires separationand purification of either of 90Sr and 90Y. We havebeen engaged in examination to improve theprocedures of radioactive Sr analysis. In thisstudy, Sr and Y were separated through yttrium
phosphate coprecipitation. Y was purified
through DGA resin solid phase extraction and
DDTC solvent extraction. Radioactivity of 89Sr
can be estimated by using combination of
measured radioactivities of Sr (89Sr + 90Sr) using
Sr Rad-Disk method and 90Sr by 90Y
measurement.

P49 Environmental dynamics of dissolved

191

radionuclides and ions in riverine waterflowing urban area after the FDNPP accident
TOMITA, R.1, MATSUNAKA, T.2, HONDA,
M.1, SATOU, Y.1, MATSUMURA, M.2,
SAKAGUCHI,
A.3,
TAKAHASHI,
T.2,
MATSUZAKI, H.4, SASA, K.2, 3, SUEKI. K.3(1Grad. School of Pure and Appl. Sci., Univ.
Tsukuba, 2Res. Facility Center for Sci. and Tec.,
Univ. Tsukuba, 3Pure and Appl. Sci., Univ.
Tsukuba, 4MALT, The Univ. Museum, The Univ.
Tokyo)
To observe the fate/dynamics ofradionuclides, which has been dispersed from
FDNPP, in river water flowing through denselypopulated area, we investigated the concentrationof dissolved radiocesium 137Cs and radioiodine
129
I and their stable isotopes (133Cs and 127I) in
riverine water, Japan. Water samples werecollected at 6 stations in the Ohori River system,
Chiba (about 200 km away from the FDNPP).
Additional two inflow waters to this river were
sampled at the same time. These samples were
filtrated with membrane filter (pore size 0.20 µm),
and the radioactivity of 137Cs in the filtrated water
was determined by HP-Ge gamma-spectrometry.
Dissolved 129I was measured by accelerator mass
spectrometry (AMS) at MALT, The University ofTokyo after the appropriate treatment of samples.
Other dissolved elements were determined by
ICP-MS. The average dissolved 137Cs
radioactivity decreased by 77% through 2012 to2015 in this river. The concentration for 137Cs
could be affected by the inflow to this river, thatis, the concentration for 137Cs was diluted with
input water which has lower concentrationcompared with that of the Ohori River. 129I andmajor cation (Ca2+ and Mg2+) concentrations insoluble fraction showed the good correlation withthose of 137Cs.

P50 Simple characterization of radiocesiumin sand sample combined with the imaging

192

plate
OCHI, K.1, KURIHARA, Y.2, TAKAHASHI, M3,
NAKAMURA, T4, KOIKE, Y4(1Grad. Sch. of Sci. and Tech., Meiji Univ.,
2Org. Strategic Coordination Res. Intellect. Prop.,
Meiji Univ., 3Dept. Admin. Safety Hygiene.
Osaka Univ., 4 Sch. of Sci. and Tech., Meiji
Univ.)A sand sample collected at the sandbox ina park at Fukushima was selected to know the
behavior of radiocesium. Fukushima-derived
radiocesium (137Cs) in the sand sample wereanalyzed by a sequential extraction procedure.
The radioactive cesium isotopes were divided
into five fractions by the procedure based on
Tessier’s method. The characterization ofradioactive cesium in the sample was achieved by
γ-ray spectrometry for each extraction residues.
About 66% of the radiocesium existed in freeoxides, organic-bound and residual material. To
acquire a two-dimensional image of sand particle,
radioactive materials in the sieved sand sample
were measured using the imaging plate for 1 day.
The radioactive materials were distributed spotty,suggesting that the number of radioactive
particles was relatively small but that theiractivity levels were relatively high. The result
indicates that radiocesium in sand sample will
have been retention to soil particle.

P51 Temporal changes in atmospheric 137Csconcentrations in Namie Town, Fukushima
OCHIAI, S.1, HASEGAWA, H.1, KAKIUCHI,
H.1, AKATA, N.2, UEDA, S.1, TOKONAMI, S.3,
HISAMATSU, S.1(1Institute for Environmental Sciences, 2National
Institute for Fusion Science, 3Hirosaki
University)
The temporal changes of atmospheric 137Csconcentration in the area with relatively highcontamination by the Fukushima Dai-ichi
Nuclear Power Plant accident were investigatedto reveal the factors affecting the concentration ofre-suspended 137Cs in the air. Aerosol samples
with larger and smaller than 1.1 Pm diameter
were separately collected during one month using
a high volume air sampler at the MinamiTsushima District in the western area of Namie
Town during October 2012 to December 2014.
The observed total atmospheric 137Csconcentrations ranged 0.042-1.1 mBq m-3 andshowed clear seasonal fluctuation with high 137Csconcentration during summer-autumn and low
during winter-spring. Most of atmospheric 137Cs
was contained in larger particles than 1.1 Pm
during summer-autumn, suggesting thatfluctuation of large particles is related to theseasonal change in the total atmospheric 137Csconcentration in this area. During the high andlow atmospheric 137Cs concentration interval,
easterly and westerly winds were dominant,respectively. The 137Cs inventory on the ground
was reported as relatively high in east direction
from the measurement site and low in west. Those
results suggest that the atmospheric 137Csconcentration at the measurement site wasstrongly influenced by larger particles from thearea with relatively high contamination.
This work was performed under contract
with the government of Aomori Prefecture, Japan.

P52 Dosimetry using milk teeth of Japanesechildren by measuring CO2 radical
OKA, T.1,2, TAKAHASHI, A.3, KOARAI, K. 2,
KINO, Y. 4, SEKINE, T. 1, SHIMIZU, Y. 3,
CHIBA, M. 3, SUZUKI, T. 3, OSAKA, K. 3,
SASAKI, K. 3, SHINODA, H. 3
(1Institute for Excellence in Higher Education,
Tohoku University, 2Graduate School of Science,
Tohoku University, 3Graduate School of
Dentistry, Tohoku University, 4Department ofChemistry, Tohoku University)
The releases of radioactive materials fromthe nuclear plant and/or from the military193

program activities result in an ionization radiation
exposure to animals and people, the precise dose
assessment is required on the point of view of theradiation protection, radiation safety, and so on.
Electron spin resonance (ESR) method is one ofa powerful tool that has been used in the study of
dosimetry of animals, especially measuring CO2
radicals of teeth which produced by the exposureof the radioactive materials and UV light. In thiswork, enamel of the milk teeth of Japanesechildren were isolated from dentine and crashedinto a grain, and then irradiated with 60Co
gamma-ray in air at room temperature with anabsorbed dose up to 1 Gy. From the dose response
curve, the detection limit of our ESR system wasestimated to be 34 mGy (+- 16 mGy).
A part of this study is the result of"Establishment of the dosimetry protocol using
milk teeth of children" carried out under theStrategic Promotion Program for Basic Nuclear
Research by the Ministry of Education, Culture,
Sports, Science and Technology of Japan.

P53 Distribution of radiocaesium in the wild
Japanese monkey (Macaca fuscata) after theaccident of Fukushima Daiichi Nuclear Power
Plant.
Urushihara, Y.1,2, Suzuki, T.3, Shimizu, Y.3, Fujita,
S.3, Kuwahara, Y.2, Suzuki, M.2, Fukumoto, M.2,
Hayashi, G.2, Abiko, R.2, Washio, R.2, Yamashiro,
H.4, Abe, Y.5, Kino, Y.6, Sekine, T.7, Shinoda, H.3
and Fukumoto, M.2(1NIRS, 2IDAC, Tohoku Univ., 3Grad. Sch. Dent.,4Fac. Agric., Niigata Univ., 5NRCPD Obihiro
Univ. Agric. Vet. Med., 6Grad. Sch. Sci., Tohoku
Univ., 7IEHE Tohoku Univ.)
We have set up a study group for theassessment of radiation effects of the accident ofFukushima Daiichi Nuclear Power Plant. In thisstudy, we collected 18 organs (femoral muscle,
longissimus muscle, masseter muscle, tongue,
diaphragm, heart, lung, liver, spleen, kidney,mBq/kg and 129I was reduced from 1124nBq/kg
to 307nBq/kg. The 129I/137Cs ratio did not change
between 2013and 2014.

pancreas, bladder, testis, brain, adrenal gland,
submandibular gland, thyroid gland and thymus
gland), peripheral blood, bile and urine from wild
Japanese monkey (Macaca fuscata) in
Fukushima prefecture and determined the activity
concentration of radionuclides in these organs.
The deposition of only 134Cs and 137Cs wasobserved in all the organs examined. The
radioactive caesium level in the skeletal muscle
was the highest and that in the thyroid gland waslowest among all the organs studied. The mean
radiocaesium concentration of skeletal muscle inmonkeys captured in Fukushima was 3,066.5 +/7,911.6 Bq/kg, in the range of 61.6 +/- 1.5 to
82,586.4 +/- 75.5 Bq/kg. There is no great
difference in the radiocaesium concentration ofskeletal muscle in each monkey which captured
in same area. Based on these results, we are now
estimating the dose of internal and external
exposure to radiocaesium in monkeys in
Fukushima.

P54 137Cs and 129I concentrations in seawater
off Fukushima Prefecture in 2013-2014
YOSHIDA, I. 1, MORIMOTO, M.1, TSUJITA,
K.1, YAMAGATA, T.2, NAGAI, H.2, TAZOE, H.3,
MATSUZAKI, H.4(1Graduate School of integrated Basic Sciences,
Nihon University., 2College of Humanities andSciences, Nihon University., 3Institute ofRadioation Emergency Mediation, Hirosaki
University, 4The University Museum, The
University of Tokyo.)Concentrations of 134Cs, 137Cs and 129I inseawater samples collected off Fukushima during
the R/V Umitaka-Maru UM-13-05 cruise in May
2013 and R/V Sinnsei-Maru KS-14-6 cruise in
May 2014, after the Fukushima Daiichi Nuclear
Power Plant (F1NPP) accident, were measured.
For concentrations of 137Cs and 129I in surface
seawater at 5km away from F1NPP in 2013-2014,137
Cs was reduced from 36.8 mBq/kg to 12.5

194

P55 Examination of the radiocesium excretion
effect by the lactic acid bacteria
OKABE, T., MORITA-MURASE, Y.
(Keio Univ.)
For the purpose of the removal of 137Csfrom the human body, the adsorption ability of thelactic acid bacterium preparation for 137Cs was
examined and evaluated. Lactic acid bacterium
preparation and 137Cs (ca.1 kBq) were introduced
into water, pH 6.8 fluid and pH 1.2 fluid,
respectively, and shaken. After 1-6 hours, the137
Cs adsorption rate of
the preparation
reached the maximum value, that is, 46% in water,
21% in pH6.8 fluid, 17% in pH1.2 fluid. By
adding potassium to the lactic acid bacterium
preparation, until 20 mmol L-1 the 137Cs
adsorption rate was reduced. However, above thisconcentration, the 137Cs adsorption rate wasalmost unchanged.
These results show the lactic acidbacterium preparation have adsorption ability for137
Cs in stomach and intestines. Therefore, theproposed method will be one of the effectivemeans to prevent radiation emergency by 137Cs.

P56 Syntheses of Novel Organic Composite
Adsorbents and Its Application for
Simultaneous Separation of Various Types ofRadioactive Nuclides in Seawater
TACHIBANA, Y.1, SUZUKI, T.1, Mohammad, C.
A.2(1Nagaoka University of Technology, 2Zhejiang
University)
Triggered by the great Tohoku earthquake
and tsunami on March 11, 2011, an enormous
amount of contaminated water containing
radioactive nuclides such as cesium, strontium,and iodine was generated by means of sustained
injections of water or seawater for emergency
cooling of nuclear cores in Fukushima Daiichi
Nuclear Power Station. Thus, promisingadsorbents for effective separation of various
types of radioactive nuclides under various
environments have been required for nuclear
severe accidents. Based on this viewpoint, novel
tannic acid-type resin combined with strongly
basic anion-exchange resin, named improved
tannic acid-type resin (ITA-02 resin) was
synthesized successfully and the adsorption
behavior of various types of radioactive nuclides
such as cesium, strontium, lanthanides, actinides,
and iodine on ITA-02 resin have been studied inseveral types of seawater at a temperature rangeof 278 - 318 K, compared with those of sometypical resins. As a result, it was found that ITA02 resin can adsorb strongly these species inseawater at room temperature. From these results,
we have proposed that ITA-02 resin is suitable forselective separation of typical radioactive
nuclides in contaminated seawater containing
radioactive nuclides from nuclear severe
accidents.

media consisting of hydrochloric acid, nitric acid,acetic acid, and hydrofluoric acid. An automatic
system assembled for this work sequentiallyseparated the elements of interest for 6.5 h. This
automatic separation system (CASSUAL) was
served for the elemental and isotopic analyses ofultra-trace elements in the tree ring samples.

P58 Trial production for gamma-ray emitting
source applied by SLA 3D printer.
SAITO, T. 1, KOIKE, Y.2, SUZUKI, R.2,
TAKAHASHI, M.3(1Shokei Gakuin Univ., 2Sch. Sci. & Tech., Meiji
Univ., 3DASH, Osaka Univ.)
When the radioactivity in environmental
samples was quantified by gamma-ray
spectrometry, geometric conditions of the sample
greatly affect the measurement.
There is a very valuable sample in theenvironmental samples. Therefore, it cannot bemeasured by physical destruction. And so, it
was attempted that the dummy gamma-ray source
is manufactured by using a 3D scanner andstereolithography apparatus (SLA) type 3Dprinter.
As a result, with the use of a reagent
involving natural radionuclide, it was possible tocreate a detection efficiency curve to match theshape of the dummy gamma-ray source.
Therefore, it has become possible to create
dummy gamma-ray source with high accuracy ina short period of time.

P57 Development and Application ofsequential separation technique for ultra-trace
multi-elements including Pu
MIYAMOTO, Y., YASUDA, K., MAGARA, M.
(Research Group for SG Analytical Chemistry,
JAEA)
Abundance and isotopic ratios of trace
uranium, thorium, lead and lanthanides inenvironmental samples play a key role toinvestigate features of the samples. Plutonium is
an artificial element which originates from
nuclear bomb tests and accidental releases from
nuclear power plants. The authors accomplishedthe development of technique for sequential
separation of U, Th, Pb, the lanthanides, and Pu
using a single anion-exchange column and mixed

P59 Radiation degradation of cable coatings
examined by positron annihilation lifetime
spectroscopy
ONODERA, K.1, OKA, T.2,1, KINO, Y.1,
SEKINE, T.2,1(1Department of Chemistry, Tohoku University,
2
IEHE, Tohoku University.)
Polyethylene is widely used for covering

195

cables in radiation environments. The radiation
degradation of polyethylene is important for thesafety of nuclear power plants and accelerators.
Nanostructure change of such polymers is
required to investigate because it correlates withthe macroscopic structure and sample properties.
In this work, we measured the change ofnanostructure (free volume) by positronannihilation lifetime spectroscopy (PALS).
High density polyethylene and low density
polyethylene were used. Electron beam wasirradiated up to 1000 kGy under vacuum at room
temperature. After the irradiation, samples were
exposed and stored in air. The change of the freevolume and the chemical structure were
measured by PALS and micro-Fourier transform
infrared (micro-FT-IR) spectroscopy.
The results of PALS suggest that there are
two type of free volume in polyethylene, whichwerecrystalline-amorphous
regionandamorphous region. Free volume size wasunchanged during the long-term storage but
positron annihilation relative intensity changed.
In HDPE, positron annihilation relative
intensitiesofthecrystalline-amorphousintermediate region decreased during long-term
storage, whereas that of the amorphous region
was unchanged. On the other hand, micro-FT-IR
results show that the amount of carbonyl groups
increased during long-term storage in particularfor HDPE. These results suggest that the differentchanges of positron annihilation relative
intensities in two regions are probably due to thedifference of the mobility of the oxidized polymer
chain.

Excellence in Higher Education, Tohoku Univ.)
A positron is an antiparticle of electron, andwhen it’s bound with an electron, it generates a
positronium (Ps). The kinetic energy of Ps
depends on that of positron, which is justgenerated. Our goal is to develop a low-energy Ps
source by applying the electric field to highpressure gas. We made a positron source bydripping 22NaCl in a metal rod (2 mm in diameter,
17 cm in length). We use a cylindrical electrode,and attach the positron source in the center. Ps
formation amount in the gas is secured, andpositron can efficiently accelerate. We estimates
positron annihilation ratio in the electrode bypositron annihilation lifetime measurement, bywhich we measure the positron lifetime by thetime difference between when a positron injects
and when it is annihilated with an electron. We
also investigate the Doppler broadening of theannihilation gamma ray in the electrode by
germanium semiconductor detector.

P60 Positron source for a positronannihilation lifetime measurement cell under
an electric field
MICHIMATA, T.1, SANO, Y.1, OKA, T.2,1, KINO,
Y.1, SEKINE, T.2(1Grad. Sch. Sci., Tohoku Univ., 2Institute for

196

P61 Structures of positronic and muonic alkali
atoms
YAMASHITA, T., KINO, Y.
(Tohoku Univ.)
Positron, which is an anti-particle ofelectron, and positive muon, which has about 207
times heavier mass, have been used as uniqueprobes and tracers for material science andatomic/molecularphysics.
The
positron
represents a large quantum effect and delocalizes
around atoms. Since annihilation gamma rays,
emitted when the positron encounters an electron,
reflect the electron momentum, the positron has
been a sensitive probe for widely distributed
electrons with low momentums. The positive
muon has about 2.2 µs and emits a positron. The
behavior is like a hydrogen nucleus, but thequantum distribution rised from the smaller mass
than the hydrogen nucleus is crutial to theresolution of muon analysis, which utilizes thelarge magnetic moment of the muon. In this work,
we calculated quantum distributions andwavefunction structures of bound and resonancestates of positronic and muonic alkali atoms.
These systems can be general models forinteractions between a positron/positive muon
and an atom because we can describe precisely
positron/muon active reactions with the valence
elecron and static interactions with inner shellelectrons. Radial distribution functions andstructures of wavefunctions of the positron/muonare revealed by non-adiabatic three-body
calculation. This work is a fundamental
investigation for positron/muon probe analysis.

obtained σm in the Ps kinetic energy ranged from
2.0 to 3.8 eV for the first time. Present result
agreed with the experimental result (below 2 eV)
and calculation. In Ar gas at a pressure of 7.5
MPa, Ps formed with the kinetic energy of 3.7 eV
and thermalized for 3 ns.

P63 Profile measurements of bremsstrahlung
γ-ray for radioactive isotope production via
photonuclear reaction at Research Center forElectron Photon Science, Tohoku University
TAKAHASHI, K., KIKUNAGA, H., TUKADA,
K., MUTO, T., KASHIWAGI, S., TOKOKU, C.,
NANBU, K., NAGASAWA, I., HINODE, F.,
KOBAYASHI, E., HAMA, H.
Nuclear chemistry and radioactive analysis
is one of the major research fields in ResearchCenter for Electron Photon Science, Tohoku
University. Radioactive isotopes have been
produced by photonuclear reaction with using
electron linac. Bremsstrahlung γ-ray is created by
the electron beam with the averaged current morethan 100 μA injected to platinum or tungsten
target. To answer various experimental
requirements, the profiles of Bremsstrahlung γrays were studied with the current experimental
configuration. It was obtained at the target
position by irradiating Nickel films with 10 μm inthickness. An energy range of measured γ-rays
was from 10 to 35 MeV within whichphotonuclear cross section of Nickel exists. 57Ni
Intensity and distribution were measured by a Ge
Semiconductor detector and Phosphor imaging
plates.
Measured FWHM of Bremsstrahlung γ-ray
is 12 mm at the target position by injecting
electron beam with FWHM width 7 mm to two 1
mm thickness Tungsten converters. The
irradiation efficiency is approximately 7 % for thecurrent sample size of a radioactive isotope
production. By Geant4 simulation with (γ, n)cross section, the radioactivity of 57Ni after the

P62 Age-momentum correlation measurementof Ps thermalization process in Argon gas
SANO, Y.1, KINO, Y.1, OKA, T.2,1, SEKINE, T.2(1Department of Chemistry Tohoku Univ., 2IEHE
Tohoku Univ.)
Positronium (Ps) consisting of a positron
and an electron is the lightest atom. Recently,
demand for the slow Ps is further increasing, due
to developing of the Ps experimental such as
production of anti-hydrogen, QED test and Ps
BEC. In this study, we investigated the Ps
thermalization process in Argon gas by the Agemomentum correlation measurement in which
positron annihilation lifetime spectroscopy andtime dependence of Doppler broadening (DB) of
annihilation photon are simultaneously obtained.
We used p-Ps annihilation gamma rays because
the intrinsic lifetime of the p-Ps (0.125 ns) ismuch shorter than the slowing down process.
Since the DB of the p-Ps is narrower than thosefrom other annihilation processes, we could
extract the p-Ps component from the energy
spectrum of annihilation photons.
The Ps slowed down from 3.7 eV to 0.6 eV
for 0.8 ns. Comparing with a kinetic model of Ps
slowing down, we determined momentum
transfer cross sections (σm) below 3.7 eV. We

197

irradiation is estimated as 1 MBq integrating all
irradiated area.

P64 Primary processes of radiolysis of suband super-critical water
Radiolytic products of coolant material understrong radiation field in water-cooled reactors are
known to give undesirable effects on nuclear
structural materials. Understanding of thefundamental processes will be of great
importance for various application fields in waterchemistry. Ionization and excitation of watermolecules by ionizing radiations initiate very fastphysical and chemical processes. Because of sohigh reactivity (short lifetime), it was difficult toobserve experimentally the temporal behaviors(spatially inhomogeneous reactions, called spur
diffusion reactions). In this work, thefundamental processes of the radiolysis of waterat high temperature and pressure conditions(HTHP) were investigated by a newly developed
picosecond time-resolved pulse radiolysis system,
and also by numerical analyses. The results
indicated that the hydrated electron (e-aq) in the
spur reaction process mainly reacts with OH atroom temperature, while that with H3O+
becomes also competitive in subcritical water.
Taking the cumulative yield variations (∆Gmolec./100eV) into account, it is suggested that
historically defined primary G-value of thehydrated electron in subcritical water (G ~ 3.6
molec./100eV) will be appropriately reexamined
to the lower value below 2.7 in neutral pH
condition, while it is rather close to it in basic
condition.

198

2015 日本放射化学会年会・第 59 回放射化学討論会
研究発表要旨集編集・発行：
2015 日本放射化学会年会・第 59 回放射化学討論会
実行委員会（代表：関根

勉）

事務局：
東北大学大学院理学研究科化学専攻 放射化学研究室内木野康志、岡壽崇（〒980-8578 仙台市青葉区荒巻字青葉6-3）
発行日：2015年9月12日（オンライン）※承諾・許可なしに本要旨集の全部もしくは一部の転載、翻訳、複写、その他の複製を禁じます。
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