CO5-1 Determination of Particulate, Inorganic and Organic Gaseous Halogens in the Atmosphere
H. Tsukada, A. Takeda, H. Kakiuchi and N. Akata

activation analysis using the KUR reactor (Pn-3) at athermal neutron flux rate of 4.9 × 1016 n m-2 s-1 for 150
s.

Department of Radioecology,
Institute for Environmental Sciences

RESULTS: Table 1 shows the collection efficiencies ofinorganic and organic gaseous halogens calculated withthree stages. The collection efficiencies of inorganic andorganic I ranged from 82.1 to 93.4% with a mean of
87.5±4.9% and from 91.3 to 100.0% with mean of
96.6±3.6%, respectively. And collection efficiencies ofinorganic and organic Br ranged from 100.0 to 101.7%
with mean of 100.3±0.3% and from 80.2 to 93.4% withmean of 88.5±5.4%, respectively. Inorganic and organic
Cl were collected 100% by this system, because Cl ofeach third stage filters weren’t detected. Although thecollection efficiency of I is the lowest among halogens,recoveries of inorganic and organic gaseous I in this system were more than 80%. And, atmospheric concentrations of course (> 2.0 m) and fine (< 2.0 m) particulate
I, inorganic and organic gaseous I from September toDecember 2006 ranged 0.17 to 0.52, 0.46 to 1.38, 1.50 to
3.44 and 1.66 to 5.94 ng m-3, respectively. We clarify theseasonal variation of each chemical form of halogens in
the atmosphere and inorganic gas-fine particle conversion
in future studies.

INTRODUCTION: Chemical species of atmospherichalogens are classified into particulate, inorganic andorganic forms. We applied a simple method for determination of particulate, inorganic and organic gaseous halogens in the atmosphere by means of simultaneously
sampling at three types of filters. In this study, we reported simple method for sampling and analysis of particulate, inorganic gaseous and organic gaseous halogens,
Cl, Br and I, in the atmosphere.
EXPERIMENTS: The sampling system consisted ofnine filters of 47 mm , which were supported in NILU
filter holders (NL-0-009) connected in a series (Figure 1).
Fine and course particulate halogens were separately collected with fluoropore filters (AF07P, Sumitomo Electric;
DOP: 0.3 m, collection efficiency: 99.99%) by cascade
impactor and backup stage. Inorganic gaseous halogens
were sampled with three cellulose filters (Whatman 41)
impregnated with 1 M LiOH in a 10% glycerol water
mixture[1]. Organic gaseous halogens were absorbed inthree activated carbon paper filters (STV-505, Kynol).
Outdoor sample air was passed at the flow rate of 10 L
min-1 during approximately two weeks. After sample collection, each filter sample was separately sealed in a polyethylene bag, and analyzed for Cl, Br and I by neutron

REFERENCES:[1] K.A. Rahn, R.D. Borys, R.A. Duce, Science, 192(1976) 549

NILU filter folder (NL-0-009)
: 66 mm

270 mmAir

Poreflon filter paper(AF07P, Sumitomo Electric)
LiOH in glycerol-water impregnated
Cellulose filter paper (Whatman41)
Activated carbon paper filter(STV-505, Kynol)

1
2
3
4
5
6
7
8
9

Pump

10 L min-1

Fig.1 Configuration figure of routine air sampling system by NILU filter folder with cascade impactor
Table 1 Collection efficiencies (%) of inorganic and organic gaseous halogens (n=5)

I
Br
Cl

Inorganic
Range
Mean ± S.D.
82.1 - 93.4
87.5 ± 4.9
100.0 - 101.7
100.3 ± 0.8
100.0
100.0

Organic
Range
Mean ± S.D.
91.3 - 100.0
96.6 ± 3.6
80.2 - 93.4
88.5 ± 5.4
100.0
100.0

採択課題番号 23002
環境中におけるヨウ素の移行動態に関する研究（財団法人環境科学技術研究所）塚田祥文，武田晃，柿内秀樹，赤田尚史（京都大・原子炉）高宮 幸一, 福谷哲，高橋知之

共同通常CO5-2

Radiometric Dating for Paleoenvironmental Study of East Asia

N. Hasebe, K. Ito, S. Ohishi1 Y. Nakano1 and M. Ogata2
Institute of Nature and Environmental Technology, Kanazawa University
1
Graduate School of Natural Science and Technology,
Kanazawa University
2
College of Science and Engineering, Kanazawa University
INTRODUCTION: Luminescence dating observes thenatural accumulated radiation damage caused by radioisotopes such as U and Th as the form of glow after stimulation by heating or lightening. The luminescence isobserved at various wavelengths and emission color of
luminescence can be recorded easily by using thermoluminescence color image (TLCI) analysis for samples artiﬁcially irradiated with gamma-rays [1]. TLCI information is then used to set luminescence dating protocol.
To date calcite veins within bentonite deposit distributedin Luzon, Philippines, where geological processes expected in a deep geological repository of radioactive
wastes from nuclear reactors are observed in natural condition, TLCI was obtained and luminesce dating was
performed.
SAMPLES: A deep geological repository of radioactive wastes from nuclear reactors is composed of several
barriers including cement and bentonite. High alkaline
groundwater might be produced through the alternationof the cement, thus the stability of bentonite during theinteraction with high alkaline groundwater is one of theimportant issues to be studied as bentonite plays an important role to prevent an outflow of the contaminatedgroundwater to the environment owing to its cation exchange and swelling properties.
To understand bentonite-alkaline groundwater reaction
with the geological timescale, it is useful to investigate asimilar phenomenon occurred in nature. There is an ophiolite suites covered with bentonite layer in Luzon, Philippines. High alkaline groundwater originated probably
from the serpentinization of mafic rocks has been circulating along cracks in a rock and bentonite layers [2]. To
determine the timescale of fluid-bentonite interaction,
calcite precipitated from high alkaline groundwater wasdated using the thermoluminescence dating method.
EXPERIMENTS: First, thermoluminescence color of
calcite samples was investigated. Samples were irradiated by gamma-ray from Co-60 with dose rate of about
1.467kGy/h at Kyoto University Research Reactor Institute. The total gamma dose were 36 kGy given for 24.5
hours on the irradiation stage, which stand off 20cm fromthe radiation source. They emit red luminescence. Paleodose was measured using this red thermoluminescenceand SARA (single-aliquot regeneration and added dose[3]) method was applied to evaluate sensitivity change of
calcite occurred through repeated heating of samples. In
annual dose measurement, we measured radioactive element concentrations of calcite and a surrounding mafic
sample using XRF, EPMA, LA-ICP-MS analyses. A
cosmic ray contribution to annual dose was calculated byan equation of [4].
To know the annual dose of a heterogeneous sample,
detailed three-dimensional rock distributions around thesample is necessary. Unfortunately, the analyzed sample
was very small in size, therefore we do not know accurate
distribution of surrounding rock facies. By assuming theratio of calcite and the surrounding mafic rock, the age of
calcite was calculated (Fig.1).
RESULTS: The order of calcite age is ~10ka(younger
than 100ka and older than 20ka). For accurate dating, it isnecessary to consider errors in added dose, exact distribution of rock which contributes the annual dose, anddevelopment of a method to estimate an annual dose for aheterogeneous sample.

Fig. 1. Age estimates under the assumption of basalt content.

REFERENCES:[1] T. Hashimoto et al., Nucl. Tracks, 16 (1989) 3-10.
[2] E.E. Geary, R.W. Kay, J.C. Reynolds and S.M. Kay,
Tectonophysics, 168 (1989) 43-63.
[3] V. Mejdahl and L. Bøtter-Jensen, Quat. Sci. Rev., 13(1994) 551-554.
[4] J.R. Prescott and J.T. Hutton., Rad. Meas., 23(1994) 497-500.

採択課題番号 23003	
 	 	  東アジアにおける古環境推定のための放射年代測定	
 
一般通常	
 
（金沢大・環日本海域セ）長谷部徳子、伊藤一充、（金沢大院・自然）大石新之介、中野靖幸（金沢大・理工学域）小形学	 CO5-3

Determination of Trace Amount of Cl, Br and I in Sedimentary Rock Samples

M. Ebihara and S. Sekimoto1
Graduate School of Science, Tokyo Metropolitan University
1
Research Reactor Institute, Kyoto University
INTRODUCTION: It is important to know the elemental composition in meteorite samples for discussing
the classification, formation mechanism and metamorphism of those samples in terms of cosmochemistry.
However, the behavior of Cl, Br and I, that is, the halogen elements in the formation and metamorphism of meteorites have rarely been studied in detail because accurate and reliable data about the abundances of the halogens, which mean Cl, Br and I hereafter, in meteorites
have scarcely been obtained.
The shortage of accurate and reliable data about theabundances of halogens in cosmochemical and also geological samples is due to difficulty in determination of
trace amount of halogen elements by using convenient
and/or conventional analytical method. In igneousrocks and sedimentary rocks, which are commerciallyavailable in National Institute of Advanced Industrial
Science and Technology, generally their Cl, Br and I
contents were reported as only preferable values or havenever been reported.
In this work, trace amount of Cl, Br and I were determined by radiochemical neutron activation analysis(RNAA) using Kyoto University Reactor (KUR) in geochemical reference samples, “Sedimentary rock series”
where recommended values are not given, but preferable
values are only given. Since, in sedimentary rock series,
only preferable values have been reported by Imai et al.
[1] for Cl, and only those preferable values [1] and experimental values using ICP-MS by Chai and Muramatsu[2] for Br and I, it is very meaningful to present reliablevalue of Cl, Br and I using RNAA, which has never beenused for analysis of sedimentary rocks.
EXPERIMENTS: Trace amount of Cl, Br and I in
sedimentary rocks and rhyorite samples were determinedby (RNAA). The preparation of reference chemical
standards, the neutron irradiation, the radiochemical separation scheme, the chemical yield determination and thedata reduction for RNAA used in this work were essentially the same as that described in Ebihara and Sekimoto[3].
RESULTS: In the nine sedimentary rocks and the threerhyorite samples, Cl, Br and I contents were determined
three to five times independently within the uncertaintiesof 2-13% for Cl, 3-13% for Br and 2-22% for I, respectively. The uncertainties quoted in the above Cl, Br and
I contents mainly depend on counting statistics in the
γ-ray measurements. The original data obtained by three
to five times RNAA in each sample are transformed, byvariance analysis, into a new set of values with uncertainties of one standard deviation, which are shown in Table
1. The halogen contents of the three rhyorites (JR-1, JR-2
and JR-3) obtained in this work are approximately consistent with the previous values by RNAA using the
JRR-4 reactor of the Japan Atomic Energy Agency,
whose thermal neutron flux is 3.2x1013 n cm-2 s-1 under
3.5MW operation [4]. In spite of the reactor characteristics and the irradiation conditions; thermal neutron flux,
irradiation time and so on, it is confirmed that the resultsof RNAA for the halogens is reproducible. We expectthat the halogen contents in the nine sedimentary rocks
are successfully obtained by RNAA in this work.
Comparing the halogen contents of the nine sedimentary rocks obtained in this work to the preferable values
reported by Imai et al. [z], our analytical values tend to belower than the preferable values except for Br contents in
JSd-1 and JSd-3. Since those preferable values are thecompiled data provided by only two or three independent
determination, the confidence level of those data is low.
Our analytical values with the uncertainties of 2-22% aremuch more reliable than those preferable values.
Table 1. Measured contents of Cl, Br and I in thenine sedimentary rocks and three rhyorites

SampleCl (ppm)

Br (ppm)

I (ppb)

JLk-1

59±2

7.83±0.53

9090±640

JLs-1

17±2

105±12 ppb

319±29

JDo-1

36±6

623±50 ppb

789±39

JSL-1

14±2

123±15 ppb

108±8

JSL-2

7.58±0.74

60±6 ppb

97±9

JSd-1

64±7

1.85±0.11090±90

JSd-2

23±2

1.13±0.04

674±63

JSd-3

26±1

3.92±0.084220±330JCh-1

4.75±0.25

27±5 ppb

115±13JR-1

982±712.07±0.06

84±3

JR-2

789±391.64±0.12

86±15

JR-3

134±120.577±0.045

482±37

REFERENCES:[1] N. Imai et al., Geostandards Newsletter, 20, 165-216(1996).
[2] J.Y. Chai and Y. Muramatsu, Geostandards andGeoanalytical Research, 31, 143-150 (2007).
[3] M. Ebihara and S. Sekimoto, KURRI PROGRESSREPORT (2010) CO5-9[4] H. Ozaki and M. Ebihara., Anal. Chim. Acta 583,
384-391 (2007).

採択課題番号 23012 隕石中期試料中の微量ハロゲン(Cl, Br, I)の中性子放射化（首都大学東京・大学院・理工）海老原 充（京大・原子炉）関本 俊

共同通常

CO5-4

Study of Earth and Planetary Matters by Thermoluminescence

Department of Applied Physics, Okayama University of
ScienceTL OF ORDINARY CHONDRITES: Induced TL(thermoluminescence), the response of a luminescentphosphor to a laboratory dose of radiation, reflects themineralogy and structure of the phosphor, and provides
valuable information on the metamorphic and thermal
history of meteorites. Especially the sensitivity of theinduced TL is used to determine petrologic subtype of
unequilibrated ordinary chondrites [1]. Natural TL, theluminescence of a sample that has received no irradiationin the laboratory, reflects the thermal history of the meteorite in space and on Earth. Natural TL data thus provide
insights into such topics as the orbits of meteoroids, theeffects of shock heating, and the terrestrial history of meteorites [2]. Natural TL properties are usually applied tofind paired fragments [3-5]. This time we measured induced and natural TL properties of twenty-eight Yamato
unequilibrated ordinary chondrites (LL3: 2, L3: 12, H3:14) from Japanese Antarctic meteorite collection. Sampling positions of these chondrites were measured byGPS.
PRIMITIVE ORDINARY CHONDRITES: Most of
the chondrites had TL sensitivities over 0.1 (Dhajala=1),
corresponding to petrologic subtype 3.5-3.9. Four chondrites, Y982042 (L3), Y982240 (L3), Y981664 (H3) andY981744 (H3) were revealed to be primitive ordinarychondrites as shown in Fig.1, petrologic subtype 3.2, 3.3,
3.2-3.3 and 3.4, respectively. It is particularly significant in understanding the nature of primitive material in
the solar system.
3.1

3.2

3.3

3.4

3.5

3.6

3.7

3.8

3.9

200

Peak Temperature (℃)

180

3mm

Fig.2. CL color image of Y-86004.
5
4
3
2
1
0

TL Subtype
3.0

Purple, blue, and red CL were recognized from inner side
to outside with concentric structure. Moreover, there is a
black layer of fusion crust at outermost region. It is suggested that this structure was made by heating during
atmospheric passage from occurrence of the fusion crust.
This time we measured raman spectra of the Y-86004.
The results were shown in Fig 3. The minerals, whichshowed these Purple, blue, and red CL, were all enstatite.

Intensity

K. Ninagawa

H3

100

300

500

700

900

1100

1300

1500

Raman Shift (cm-1)

L3
LL3

Y982042160

Fig.3. Raman spectra of the Y-86004.

140
120
100

Y982240
Y981621
Y981744

80
60
40
0.001

Y981664

0.01

0.1

1

10

TL Sensitivity (Dhajala=1)

Fig.1. Induced Peak Temperature vs. TL Sensitivity tosearch primitive ordinary chondrites

ENSTATITE CHONDRITE:
Fe-poor forsterite,
Fe-poor enstatite and feldspar in meteorites have a phosphorous characteristics to exhibit the cathodoluminescence (CL) [6]. Y-86004 (EH melt rock) was reported
that it had CL zoning [7]. Fig.2 shows it’s color CL image.

採択課題番号 23016

RERERENCES:[1] D. W. G. Sears et al. 1991. Proceedings of Lunar andPlanetary Science 21:493-512.
[2] P. H. Benoit et al. 1991. Icarus 94: 311-325.
[3] K. Ninagawa et al. 1998. Antarctic Meteorite Research 11:1-17.
[4] K. Ninagawa et al. 2002. Ant-arctic Meteorite Research 15:114-121.
[5] K. Ninagawa et al. 2005. Antarctic Meteorite Research 18:1-16.
[6] Steele (1990): In Specrtoscopic characterization ofminerals and their surfaces. (ed. Coyne et al.), pp.
150-164. American Chemical Society.
[7]K. Ninagawa et al., 2000. 25th Symposium on Antarctic Meteorites (NIPR, Tokyo), 114-116.

熱ルミネッセンスによる地球惑星物質の研究（岡山理大・理）蜷川清隆、田原吏、内川 貴浩、西戸

裕嗣、鹿山

一般通常
雅裕、土屋

裕太

CO5-5Size Distribution of Metal Elements in the Atmospheric Aerosols at Sakai, Osaka

N.Ito, A.Mizohata and Y. Nakano1
Radiation Research Center, Osaka Prefecture University,
1Research Reactor Institute, Kyoto University
The fine particle in the atmosphere in which someelements are toxic and can enter the human lung causes
the healthy effects. So we observed the element in thefine particles at Sakai, Osaka. This report shows the size
distribution of V, Ni, Zn , the concentration ration of fineand coarse particles and the difference of concentration
between the soil and particles.
Table 1. Analysis factors in neutron activation analysis
using KUR
Irradiation
SystemIrradiation timesec

V, Al, Ca, Cl, Mn

PN1

120

Na, K, Cr, Fe, Ni,Zn

PN2

7200

Elements

The particles in the atmosphere were collected by the lowpressure Andersen sampler with which the particles wereseparated on 13 stage by the particle size . The sampler

have collected the samples in 2 weeks at Osaka
Prefecture University, Sakai, Osaka. 4 samples whichwere collected in 2011 were analyzed for the element
concentrations by the neutron activation analysis using
Kyoto University Nuclear Reactor(Table 1). The gammarays emitted from irradiated samples were measured by
Ge solid state detector and 4096 channel pulse height
analyzer system.
In this report we show the results of the size distribution
on V, Cr and Zn in the aerosols that were collected in
May 2011 at Sakai, Osaka(Fig.1). The median of these islocated at the fine particle range (<2.1μm) and these
medians differ in the position, 0.21～0.51μm(V), 0.13～
0.21μm (Ni) and 0.51～0.22μm(Zn).
We compere the rations of these elements between the
average in soil and the rations in the coarse(>2.1μm) andfine particles(<2.1μm)(Fig.2). The ration of V,Cr, Ni and
Zn to Fe in the soil are less than 1/500. By the contrast in
the aerosols, the ration raise more than 2 times, especially
Zn raises more than 10 times. This raise could be causedby the metallic fine particles from the metal productindustry , the incinerator or oil burning.

採択課題番号 大気エアロゾル粒子のキャラクタリゼーション共同通常( 大阪府大産学官 ) 伊藤憲男、溝畑 朗、 ( 京大原子炉 ) 中野幸廣

CO5-6

Estimation of Fe Vacancies of Natural Magnetite in San'in Coast Region
by Mössbauer Spectra

H. Matsuyama, K. Shinoda and Y. Kobayashi1
Department of Geosciences,
Graduate School of Science, Osaka City University
1
Research Reactor Institute, Kyoto University
INTRODUCTION: Magnetite is a typical magnetic
mineral which is widely included in natural rocks andsands. The crystal structure of magnetite is inverse
spinel type. Chemical compositions of magnetite varyfrom [Fe3+]A[Fe3+, Fe2+]BO4 to [Fe3+]A[Fe3+5/3, □1/3]BO4,
where □ indicates vacancy in B site. Since the vacancy is controlled by oxygen fugacity, quantitative analyses of vacancy of natural magnetite are of interest to
estimate rock's environments. Experimental methods tomeasure vacancies of magnetite are X-ray diffraction
analyses and Mössbauer spectra measurements. In thisstudy, vacancies of natural magnetites included in granites and sands distributed in San'in coast region ofSouth-West Japan are estimated from X-ray and Mössbauer analyses.
EXPERIMENTS: Natural magnetites in San'in regionof 18 different localities were separated. The occurrencesof natural magnetite are fresh granite, weathered granite,
river sand and sea sand. Chemical compositions of 18
natural magnetites were measured using SEM-EDS.

TiO2 and Al2O3 were detected as solid solution components. Mössbauer spectra of natural magnetite were
measured at Seto Lab. Powdered magnetite of 10mg
were mixed well with powdered agarose of 100mg andpressed into a pellet. The pellet was exposed to γ-ray
generated from 57Co for 24 hours. By fitting the measured spectra by Lorentz function, peak area due to Fe in
A and B sites are calculated. Vacancy ratio was estimated from the ratio of peak area of A and B sites. In
the estimation of vacancies of natural magnetite, which
often contain TiO2, it was assumed that the ulvöspinelcomponent do not contribute to the magnetic splitting.
RESULTS:
Fig.1 indicates vacancies in mol% of 18 magnetites.
Numbered samples are from granite. Last 3 samples arefrom river sand and 2 sea sands, respectively. Circled
plots are from weathered occurrences judged by theirappearances. All 18 samples showed vacancies below
10%. Among 18 samples, magnetites in weathered occurrence tend to show slightly high vacancy as much as
5%. In contrast, magnetites in fresh granite tend toshow very low vacancy. This results imply that vacancy
in magnetite is a possible indicator of weathering ofrocks.

Fig.1 vacancies of natural magnetites in San'in coast region.

採択課題番号 23029	
 メスバウアースペクトル測定による
山陰海岸地域の天然の磁鉄鉱の空孔量測定（大阪市大・理）松山寛、篠田圭司（京大・原子炉）小林康浩	
 

共同通常	
 

CO5-7

Determination of Abundance of Rare Metal Elements
in Seafloor Hydrothermal Ore Deposits by INAA Techniques

J. Ishibashi, M. Ooki, T. Yamanaka1, Y. Furuzawa1,
T. Noguchi2, R. Okumura3 and K. Takamiya3
Faculty of Science, Kyushu University
1
Faculty of Science, Okayama University
2
Center for Advanced Marine Core Research,
Kochi University
3
Research Reactor Institute, Kyoto University
INTRODUCTION: To meet recent increased demand
for rare metal elements as mineral resources, high sensitive multi-element analysis becomes more important as
geochemical tools for mineral exploration. Instrumental
neutron activation analysis (INAA) has the advantage of
non-destructive analysis and is free from problems thatconcentrate of a specific element is often included in residue during acid dissolution. Previous studies havedemonstrated that INAA enables rapid abundance determination for multi elements in ore samples collectedfrom active seafloor hydrothermal fields that consist ofvariety of sulfide/sulfate/silicate minerals [1,2]. In order
to extend the range of application of this technique, westarted preliminary studies using samples of hydrothermal sulfides and hydrothermal sediment.
EXPERIMENTS: Two groups of natural samples were
provided for this study. One was hydrothermal sulfide/sulfate ores collected from active hydrothermal
fields in the Okinawa Trough, and the other was hydrothermal sediments collected from Wakamiko submarine
crater in the Kagoshima Bay.
For analysis of long-lived nuclides (110mAg, 59Fe, 203Hg,
124
Sb, 65Zn) and mid-lived nuclides (76As, 198Au, 131Ba),
samples were irradiated at Pn-1 (thermal neutron flux =3.86×1012 n/cm2/sec at 1 MW) for 4 hours, and the gamma ray activity was measured for 3 hours after around 30
days cooling and for 50 minutes after 3-10 days cooling,respectively. For analysis of short-lived nuclides (66Cu,
56Mn), samples were irradiated at Pn-3 (thermal neutron
flux = 4.86× 1012 n/cm2/sec at 1 MW) for 1-3 minutes,
and the gamma ray activity was measured for 5 minutes
after 10-30 minutes cooling. Concentration of each element was calculated by comparison of gamma ray intensities between the sample and standard materials; Na forshort-lived nuclides measurement and Co for mid- andlong-lived nuclides measurement.
RESULTS: Fig. 1 shows compilation of abundance ofgold (Au) and silver (Ag) in ore samples collected fromseafloor hydrothermal fields. Results obtained by thisstudy well agree with previous studies [1,2]. Not a few
ores from the Okinawa Trough showed notable enrichment in silver (Ag).

Fig. 1 Abundance of Au and Ag in ore samples collected from active hydrothermal fields in the Okinawa
Trough, with data compilation from other active hydrothermal fields.

Fig. 2 shows an example of vertical profiles of elemental
abundance in hydrothermal sediment collected from
Wakamiko crater. The profile of gold (Au) content
showed good correlation with those of arsenic (As) andantimony (Sb).

Fig. 2 Vertical profiles of As, Sb and Au concentrations
in sediment samples collected from Wakamiko submarine crater.

As demonstrated above, INAA provided useful information for discussion on potential of mineral resources ina seafloor hydrothermal field.
REFERENCES:[1] T. Noguchi et al., Geochem. J. 41, 141-148 (2007)[2] T. Noguchi et al., J. Mineral. Petrol. Sci., 106, 26-35(2011)

採択課題番号 23039
海底熱水鉱床中の微量元素存在度の解明（九州大・理）石橋純一郎、大城光洋（岡山大・理）山中寿朗、古澤祉子（高知大・コア研）野口拓郎（京大・原子炉）奥村 良、高宮幸一

共同通常

ESR Study on -Irradiated Agricultural Wastes for Arsenic Absorber

M. Minagawa, M. Shimizu, and N. Sato1
Graduate School of Science and Engineering, Yamagata
University
1
Research Reactor Institute, Kyoto University
INTRODUCTION: We have conducted the following
two different experiments emerging from previous cooperative venture in this period: (1) solid state polymerization of acrylonitrile (AN) by electron bombardment (EB)and (2) -irradiation on wasted agricultural products. In
this report, we describe the latter topic selectively.
Since some agricultural wastes are known to absorb hazardous molecules such as Arsenic (As), this topic hasserious meaning from a point of view of environmental
science in the 21st century. Our previous studies revealed that -irradiation enhances such capability. Here
we report ESR results of -irradiated agricultural wastes
to investigate the effect of radical concentration.
EXPERIMENTS: Three kinds of agricultural products
were used (rice chaff, its heat-treated one, and green tea).
These were packed in glass bottle and -irradiated atroom temperature in Koga Isotope Co. Ltd. (Shiga Prefecture). The total irradiation dose rate was 100 and
200 kGy. ESR measurements were carried out by ESR
spectrometer installed at KURRI to estimate the radical
concentration in the bulk sample, the extent of which is
directly proportional to the adsorption capacity of poisonous As contained in contaminated drinking waterfrom the earth (underground) [1]. As adsorption property was evaluated by using color identification test established by Merck Co. Ltd.
RESULTS AND DISCUSSION: When the agricultural products were heated up to a high temperature(>400 °C) under imperfect oxidative conditions by using
an electric furnace, they turned from yellow to black in
its color with the increase of temperature. The radical
concentration was evaluated in terms of a calibration
curve of ESR (DPPH/KBr, internal standard). That is,
the radical concentration was dependent strongly on theheating rate employed. In general, the slower the heating rate, the higher the radical concentration, up to theheating upper-limit 400 °C. Other independent experiments showed that the absorption capacity of poisonous
As by heat-treated agricultural products is directly proportional to the radical concentration in the bulk sample[1]. The higher the radical concentration, the larger theabsorption capacity. Therefore, -irradiation effect on
the efficiency of absorption capacity would be expected.
Fig.1 shows ESR intensity against the dose of
-irradiation. It is apparent that original rice chaff(symbol A) is very strong against -irradiation, since its
radical concentration is very low and is little affected.
In the case of heat-treated rice chaff (~350 °C) (B), intensity became larger. Radical concentration increased
gradually at lower doses and became saturated at higher
doses.
In green tea (C), the intensity much larger andthe concentration increased linearly. From Fig.1, we
can evaluate what kind of behavior is observed byheat-treatment and to what extent the radical concentration varies by -irradiation according to the difference of
the kinds of agricultural products. Namely, in order toobtain some specified radical concentration one can understand what kinds of operation should be taken from apoint of functional design of wasted agricultural products.

C
ESR signal intensity

CO5-8

B

A
0

100

200

Dose / kGy
Fig.1 The effect of -irradiation on the signal intensity of ESR of three kinds of agricultural products ( A,rice chaff; B, heat-treated rice chaff; C, Green tea).
REFERENCES:[1] M. Minagawa, W. Katsumi, M. Shimizu, T. Matsuyama, N. Sato, to be published in Spring Conference of
MLS Society, 2013.
Acknowledgement: Special thanks are expressed toProf. T. Yoshiie for his kind help in EB experiments.

採択課題番号 23㪇41
放射線を利用したアクリロニトリルの固相重合反応（山形大院・理工）皆川雅朋、清水 信、（京大・原子炉）佐藤信浩

共同通常

CO5-9 Measurement of Environmental Radioactivity and Heavy Metal in Seaweed Samples
T. Ohta, T. Kubota1, Y. Mahara1, T. Fujii1, S. Fukutani1, S. 2.1 Measurement of 137Cs in algae samples by gamSekimoto1 and K. Takamiya1
ma-ray spectrometer
After seaweed samples were stored into U-8 plastic botFaculty of Engineering, Hokkaido University
1tle
and/or Steel container, Cs-137 in seaweed samples
Research Reactor Institute, Kyoto University
were measured by gamma-ray spectrometer (Isotope
INTRODUCTION: The devastating tsunami caused center, Hokkaido Univ.).
by the great earthquake (Mw = 9.0) off the coast of 2.2 Neutron irradiation
northeastern Honshu on 11 March 2011 destroyed large About 10 – 100 mg of algal sample was sealed in clean
areas along the coasts of Eastern Honshu in Japan. At plastic bag. The samples and reference standard samples
Fukushima NPP, however, the standby power system was were packed in an irradiation capsule. Neutron irradiation
destroyed by the tsunami, disabling the cooling systems was carried out for 3-5 minutes using a pneumaticof the reactors. The loss of cooling resulted in the release transport system (Pn-1) at the Research Reactor Institute,of radionuclides, including 131I (T1/2 = 8.1 days), 134Cs Kyoto University (KUR). After irradiation, γ-rays emit(T1/2 = 2.1 years), and 137Cs (T1/2 = 30 years), into the ted from the samples were successively measured by a
Ge detector. The iodine concentration in the samples was
atmosphere from the Fukushima NPP.
The iodine content in seawater consists mainly of two determined by counting γ-rays emitted from correspondisotopes, 127I and 129I. 129I (half-life 15.7 million years) is ing nuclides produced by (n,γ) reactions.
129 127a radionuclide produced by cosmic-ray-induced spalla- 2.3 Measurement of I/ I ratio by AMS
tion of Xe in the atmosphere and by spontaneous fission The iodine isotopes 127I and 129I were isolated
from marine algal samples to obtain 129I/127I ratiof uranium in the Earth’s crust.
129 127
In the pre-nuclear era (i.e., before 1945), the I/ I os by means of accelerator mass spectrometry
ratio in natural seawater was reported to be less than 10-11. (Mutsu, JAEA, Japan, and Malt, Tokyo Univ.). The deHowever, after 1945, the amount of 129I in seawater in- tailed separation and measurement of 129I/127I in seacreased substantially owing to the release of this isotope weed was written by Mahara et al. and Ohta et al. [1,2].
from nuclear fuel reprocessing plants and nuclear weap137
ons testing; consequently, the 129I/127I ratios in seawater RESULTS: The Cs in seaweed samples in 2009 andand in marine algae have increased by several orders of 2010 were observed to be detection limit, while after
Fukushima Nuclear disaster 66 Bq/kg in Ibaraki prefecmagnitude compared to pre-1945 values.
129 127
137
In this study, we measured I/ I and Cs in marine ture and 545 Bq/kg in Fukushima prefecture. The
129I/127I ratios observed in algae collected fromalgae before and after Fukushima Nuclear disaster.
1928 to 1987 ranged from 10-13 to 10-10. The
129
EXPERIMENTS: Seaweed samples were collected
I/127I ratio in algae collected from 1987 was 100
at Easter part of Japan from 2009 to 2011. (Fig. 1)- 1000 times as high as the ratio measured in algae from before 1945. This dramatic increase in
129I/127I ratio after 1945 was attributed to humanactivity.
REFERENCES:[1] Y. Mahara, T. Ohta, T. Tokunaga, H.
Matsuzaki, E. Nakata, T. Nakano, T. Kubota, and H. Yasuda, Nucl.Instr. Meth. Phys. Res. B (2012) (accept).
[2] T. Ohta, Y. Mahara, T. kubota, T. Abe, H. Matsueda, T.
Tokunaga, H. Matsuzaki, Nucl. Instr. Meth. Phys. Res. B(revise).
A part of this study is the result of “Kurashini manabu
monodukuri ”carried out under Sekisui Kgaku Co Ltd.

採択課題番号23053 現世から過去 100 年間の海藻中の環境放射能と重金属類の測定 共同通常
（北大・工学研究院）太田朋子、（京大・原子炉）馬原保典、窪田卓見、福谷 哲、藤井俊行、
関本 俊、高宮幸一

CO5-10

Cathodoluminescence Study of Nanodiamond Formation in Meteorites

H. Nishido
Research Institute of Natural Sciences,
Okayama University of Science,
INTRODUCTION: Diamonds play a key role not only
in material sciences, but also in the Earth and Planetarysciences. Natural and experimentally grown diamonds aswell as their cathodoluminescence properties have been
described from different origin such as metamorphic
rocks, Chemical Vapor Deposition, High-Pressure
High-Temperature (HPHT), Ultradispersive Detonation
Diamonds (UDD), meteorites and meteoritic craters.
They have clearly demonstrated that cathodoluminescence permits a rapid, non-destructive method of detecting defect symmetries in diamond samples from different
origin.
Commonly, nanodiamond characterization has focusedon chemical and physical properties with only limited
luminescence spectroscopic investigations. In this study
neutron implication experiments were conducted ongraphite to clarify the formation mechanism of nanodiamonds by assuming neutron irradiation process at the
KURRI. Here, we present the results of a study of scanningelectronmicroscope-cathodoluminescence(SEM-CL) microscopy and spectroscopy of micro-and
nanodiamonds from different origin. The purpose of thesemeasurements is to investigate the capability of the
SEM-CL technique to document temperature-related effects on diamond samples at room (RT) and liquid nitrogen (LNT) temperature, if there is a systematic differencein CL properties between diamond samples of different
sources, to determine whether CL characteristics of diamond could be indicative of the astromineralogical application [1].
SAMPLES AND METHODS: The samples for CL
measurements were mounted in two-component epoxy
resin with non-luminescence. Their polished thin sections
with 20 μm thickness were preliminary examined under apolarized microscope to clarify the textures indicating
carbon materials. Their surfaces were finished using silicon colloidal with a grain size of 100 nm, and coatedwith amorphous carbon.
CL spectra were obtained using a scanning electron microscope-cathodoluminence (SEM-CL), which comprises
the SEM (JEOL: JSM-5410) combined with a grating
monochromator (Oxford: Mono CL2). The SEM-CL system was operated at 15 kV accelerating voltage and acurrent of 1.5 nA. CL spectra were recorded in the rangeof 350-800 nm and a dwell time of 1 second per step byphoton counting. All CL spectra were corrected for total
instrumental response. Raman spectra were obtained
from the polished samples using a laser Raman microscope (JASCO: NRS-2100) located at the KURRI.

RESULTS & DISCUSSION: Cathodoluminescence
spectra of the natural diamond sample show a significant
broad band centered at 541 nm at both room (RT) andliquid nitrogen (LNT) temperature. Compared to CL
spectrum obtained at RT, an additional weak shoulder
peak appears at 488 nm at the LNT with a relatively highpeak intensity. The grain sizes of these diamond samples
fall into a few hundred micrometers.The RT-CL spectrumof the synthetic diamond (HPHT) is dominated with abroad band centered at 540 nm, whereas the LNT-CL
spectrum shows a broad band at 590 nm. Both CL spectra
have two additional bands at around 445 (448 nm at RT
and 444 nm at LNT) and 729 nm, which became dominant at the LNT spectrum.
The CVD diamond sample is dominated by a noisy broadband ranging from 370 to 400 nm in otherwise almost no
CL spectral features obtained at room temperature. A
broad band centered at 509 nm with a shoulder peak at
489 nm is dominant in the CL spectrum CVD specimen
at LNT. The maximum grain size of these diamond samples is around 250 nm.
All CL spectra (RT) of the UDD samples are dominatedby two broad bands at 388 and 462 nm, whereas spectra
obtained at LNT exhibit only one but a significant broadpeak, which is centered at around 540 nm. It is important
to note that as a function of increasing size of thenanodiamond particles, there is a gradual change of thepeak intensities.In contrast to the HPHT and CVD samples, CL spectrum of the meteoritic nanodiamond from
Boroskino sample shows a broad band centered at 540
nm at RT.
The agglomerates are called A-Centers when occur aspairs of nitrogen atoms, which centered at around 390 nm
in CL spectra, especially in type IaA diamonds. The
B-centers as four nitrogen atoms surrounding a common
vacancy and mixtures of them may also occur mostly inthe type IaB diamonds. Type Ib – mostly represented insynthetic diamonds but very rare (about 0.1%) among
natural diamonds – contain nitrogen as isolated single
nitrogen atoms called C- Centers (centered at around 450nm). In some cases, type I diamonds may also containclusters of three nitrogen atoms called N3-Centers.
CL spectra from these nanodiamonds show substantial
similarities but also some slight differences, whereas theassignment of emission bands at around 535 nm is notalways straightforward, but corresponding to dislocation
defects associated with nitrogen atoms. Although it was
not possible to define exactly the aggregation status of
nitrogen atoms, the CL spectra suggest a low concentration of nitrogen in the nanodiamonds and give some indications for distinguishing diamonds. A nitrogen content
typically less than 20 ppm can be sufficient to provide theluminescence of diamond.
Reference:[1] Gucsik, A, Nishido, H., Ninagawa, K., Microscopy &Microanalysis (in print).

採択課題番号  ‫ޓ‬隕石ナノダイアモンドの形成に関する研究（岡山理大）西戸裕嗣、蜷川清隆、鹿山雅裕、土屋裕太、田原吏（京大炉）徐虬౒หㅢᏱ

CO5-11

Determination of the Uranium Content in Moldavite
for the Absolute Evaluation of Fission-track Ages

T. Suzuki , K. Takamiya 1 and R. Okumura 1
1

Faculty of Education, Kagoshima University
Research Reactor Institute, Kyoto University

INTRODUCTION: Absolute evaluation of fissiontrack ages for geological glasses instead of the socalled isothermal (or isochronal) plateau method ortrack-size correction method which uses the thermal
annealing of fission tracks, have been tentatively
applied to moldavite, a candidate age standard [1]. In
this study, reactor neutron irradiation was employed
only for uranium determination. Fission-track ages ofmoldavite and other glass materials can be calculatedusing the effective range of spontaneous fission tracks
and the uranium content data. The effective range of
tracks can be estimated from etch-pit parameters withthe general etching rate for a polished surface
according to the measurement of natural tracks onsilicone replicas using a confocal laser ablation
scanning microscope. These procedures allow thefission-track ages of geological glasses to be
determined without direct handling of neutronirradiated materials.
EXPERIMENTS: The uranium content of samples
was estimated from normal fission-track analysis ofseparate fragments of samples using a polycarbonate
external detector and IRMM-540R uranium monitor
glass. Fission-track analysis remains an excellent andconvenient method for uranium microanalysis ofnatural glasses. M oldavite samples collected from
Jankov in southern Czech Republic were provided by
Dr. G. Biggazzi (CNR, Pisa, Italy). Neutron irradiation
was carried out using the pneumatic tube of TC
graphite facility at the KUR Kyoto University Reactor(5 MW/h) for 2–4 h. Polished and nonirradiatedmoldavite samples were etched in 46% HF at 20˚C for
15 min and polycarbonate films were etched in 6 N
NaOH at 20˚C for 12 min.

moldavite determined in this study was 2.11 +/– 0.04
and 2.21 +/– 0.04 μg/g for the two samples according
to a comparison of track counting data between thesamples and IRMM-540R monitor glass. The age ofthe moldavite was estimated at about 14 M a using
these uranium content data and etch-pit parameters.
The results are in good agreement with the reference
values and data obtained employing the normal
fission-track method with the thermal annealing of
tracks.

Fig.1. Spontaneous fission tracks in moldavite
Scale bar: 10 μm

Fig.2. Induced tracks on polycarbonate film
Scale bar: 10 μm
REFERENCES:[1] M.L. Balestrieri et al. in Van den haute, P. & De
Corte, F. (eds.), Advances in Fission Track
Geochronology (1998) 287–304. Kluwer Academic
Publishers, Dordrecht.

RESULTS: Examples of spontaneous fission tracks inmoldavite and induced tracks on polycarbonate films
are shown in Fig. 1 and Fig. 2. The uranium content of

採択課題番号 23067 FT 法によるテクタイトおよびアパタイト標準試料のウラン定量（鹿児島大・教育）鈴木達郎，（京大・原子炉）高宮幸一、奥村 良

一般通常CO5-12

Determination of Nb and Zr in Geological Standard Rock Samples
by Instrumental Photon Activation Analysis

N. Shirai, S. Sekimoto1, S. Otsuka and M. Ebihara
Department of Chemistry, Tokyo Metropolitan University
Research Reactor Institute, Kyoto University

1

INTRODUCTION: Cations like Zr, Nb, Hf and Ta are
relatively small in size and high in charge, and aregrouped into high field strength elements (HFSE). Suchelements pairs as Zr-Hf and Nb-Ta, which have similar
ionic radius at the same valency states, are well known tobehave in a similar way during igneous processes such as
partial melting and fractional crystallization. As theseelements are classified into refractory elements in cosmochemistry, element pairs represented by Zr-Hf and
Nb-Ta behave similarly during cosmochemical processes.
However, recent studies using improved analyticalmethods such as ICPMS indicate that the fractionationsof Zr-Hf and Nb-Ta in cosmochemical and geologicalsamples can occur [e.g., 1]. Therefore, Zr/Hf and Nb/Ta
ratios provide useful information about condensation
processes and igneous processes.
Various analytical methods represented by XRF, INAA,
IPAA, ICP-AES and ICP-MS were applied for determination of HFSE. Among these analytical methods,
ICP-MS has been increasingly used. There are some analytical problems when analytical method accompanying
acid digestion such as ICP-MS is used. HFSE often involve in creating analytical problems such as incompleteacid digestion and instability in solution. As Nb is monoisotopic element, it is difficult to obtain accurate Nbvalues by using ICP-MS. In this study, we used IPAA for
determination of Zr and Nb abundances for cosmochemical and geological samples. As IPAA is non-destructive
methods, this is exempted from above-mentioned analytical problems for analytical method accompanying aciddigestion. The aim of this study is to evaluate our Zr and
Nb data for geological samples and cosmochemical samples compared with their literature values.
EXPERIMENTS:
Five GSJ standards materials
namely JA-2 (andesite), JB-1 (basalt), JB-3 (basalt), JG-1
(granodiorite) and JR-1 (rhyolite) were analyzed by
IPAA. For cosmochemical sample, Allende meteorite
was used. Chemical reagent sample, Fe2O3 (99.999 %,Soekawa Chemical Co., Ltd), was irradiated to correct
the spectral interference of 52Mn formed by the54
Fe(γ,pn)52Mn reaction. For determination of Nb and Zr,
SPEX solutions for Nb and Zr were dropped on the filter
paper. Samples were taken into a sample container (9mmφ) made of highly Al foil (Al: 99.5 %, Niraco Co.,
Ltd.). Five to ten samples were stacked, among whichthin foil disk (9 mmφ) of Au as a monitor of the intensityof photon are placed. Samples in a block were put in aquartz tube. We used a linear electron accelerator at the

Research Reactor Institute, Kyoto University. Electrons
were accelerated by the linear accelerator to about 30
MeV. After irradiation (about 30 hours), samples weretaken into new Al foil and measured at the Laboratory ofRadioisotopes, Tokyo Metropolitan University.
RESULTS: Niobium and Zr abundances were determined by using the 909.2 and 934.5 keV gamma-ray of89
Zr and 92mNb, respectively. As reported by Kato andMatsumoto [2], 934.5 keV peak of 92mNb were caused bya spectral interference for 935.5 keV peak of 52Mn. Its
contribution was corrected by using 934.5 and 1434.1
keV peak of chemical reagent (Fe2O3). Contributions of52
Mn were about 3 % for JB-1, 45 % for JB-3, 7 % for
JA-2, 0 % for JR-1 and 8 % for JG-1. Our Zr and Nb
abundances for five geological standard materials werecompared with their reported values in Table 1. Our Nb
and Zr values for five geological standard materials except for JB-3 are in good agreement with the corresponding reported values. Discrepancy for Nb of JB-3 isdue to the relatively high spectral interference from 52Mn.
As shown in Table 1, there is difference of Zr abundance
for JG-1 between ICP-AES and ICP-MS, and othermethods. Analytical methods with acid digestion represented by ICP-AES and ICP-MS reported the lower Zrabundances in JG-1 compared with those of other methods. In consideration that granodiorites such as JG-1
contain zircon as accessory minerals and Zr is more partitioned into zircon than other minerals. As zircon is anacidic refractory material, it is hardly dissolved underacid digestion. As a result, Zr values from ICP-AES and
ICP-MS are lower than those from other methods (e.g.,
IPAA). Our Zr values for JG-1 are significantly higher
than literature values obtained from ICP-AES and
ICP-MS and are consistent with reported values obtained
from IPAA. Except for Nb for JB-1 and Zr for JG-1, theprecision expressed as the relative standard is 4 % for Nb
and Zr. The relatively high RSD for Nb of JB-3 is due tohigh spectral interference from 52Mn. Our RSD value for
Zr in JG-1 is higher. It is likely that zircon is heterogeneously distributed in JG-1.
Table 1. Analytical results for geological standard materials for Nb and Zr.
JB-1
JB-3
JA-2
JG-1
This work* 36.4 (3.6)
1.95 (25)
9.16 (2.6)
12.9 (3.6)
2.40
12.0
PAA
35.0
Nb (ppm)
ICPES
32.9
2.73
9.30
10.2
34.91
2.10
9.27
11.5
ICPMS
XRF
30.5
2.58
9.33
12.4
This work* 134 (1.9)
87.5 (0.7)
88.8
PAA
134
ICPES
146
96.4
Zr (ppm)
135
95.5
ICPMS
INAA
168
93.5
XRF
147
96.5
*The values in brakets are RSD (n = 3).

104 (0.4)
120
110
111
114

138 (20)
135
59.2
27.7
135
113

JR-1
15.1 (3.4)
16.9
16.1
15.3
15.1
105 (3.6)
102
93.7
98.1
127
100

REFERENCES:[1] C. Münker et al., Science, 301 (2003) 84-87.
[2] T. Kato and K. Matsumoto Geostand. Newsl., 5(1981) 167-170.

採択課題番号 23074	
 宇宙化学的試料の光量子放射化分析	
 （首都大学東京・大学院・理工）白井	  直樹（京大・原子炉）関本	
  俊	
 
	
 

共同通常	
 

Determination of Iron and Manganese in the Sediments
under Hypoxia with High Time Resolution

Graduate School of Arts and Sciences, The University ofTokyo
1
Research Reactor Institute, Kyoto University
INTRODUCTION: Hypoxia, known as dead zones
with little dissolved oxygen (DO) in the bottom watermass, has expanded since the 1960s on sea coasts all over
the world and has greatly influenced ecosystems and inshore fisheries [1]. At the seabed in Tokyo Bay, vast
dredged trenches have been formed sporadically along
the coasts by reclamation of the foreshore since the 1970s[2]. Although the water depth of the coastal Tokyo Bay isfrom 5 to 10 meters, the water depth of some dredged
trenches reaches 30 meters. In particular, the dredged
trench off Makuhari has the maximum area and depth,and strong hypoxia has been observed there due to thestagnation of water currents. In this study, sediment cores
were collected from the Makuhari dredged trench andconcentrations of iron and manganese in sediments wereanalyzed by activation analysis with high time resolution.

water is oxidative condition, i.e. winter season, on theother hand, concentrations have decreased due toeluviations of Fe2+ and Mn2+ when condition of seawater
is anoxic like hypoxia. Figure 2 shows vertical distributions of iron and manganese in the sediments collected atboth dredged and non-dredged area. Each layer corresponds to ca. 0.5 year age of sedimentation. At station
OC (●) and OD (■) which were dredged area, concentrations of both elements decreased near the surface. On theother hand, at station OE (△) which was non-dredgedarea, concentrations of both elements were almost constant at the surface. During the sampling periods, it wassuch anoxic condition that blue tide had occurred all overthe coast of Tokyo bay. This fact indicated that strong
hypoxia occurred at dredged area had been recorded at
the surface of sediments.
Tokyo light beacon
Dredged trench

14
12
-1

K. Shozugawa, T. Okoshi, T. Yamagata, R. Okumura1, K.
Takamiya1 and M. Matsuo

Dissolved Oxygen / mgL

CO5-13-1

under 3.6mgL : hypoxia

10
8
6
4
2

EXPERIMENTS: In the dredged trench (station OC
and OD, water depth was over 25 m), the seabed was
muddy and DO level of bottom water was 0 mg∙L-1 under
5 m. In contrast, the non-dredged seabed (station OE,
water depth was less than 10 m) was sandy. Both cores
were cut in the vertical direction at 0.6 - 3.0 cm intervals
after freezing. 50mg of dried (110°C, 2 hours) sediments
were packed in double polyethylene film bags. All samples were irradiated at the pneumatic tube, Kyoto University Reactor (KUR). Gamma-ray measurements wereapplied to 2 methods depending on half-lives of 56Mn and
59
Fe. For analysis of 56Mn, samples were irradiated for 10
seconds at 1MW, and then gamma-ray was measured for
600 seconds (live time) by Ge detector. Regarding 59Fe,
irradiated for 20 min at 1MW. Measurement time of
gamma-ray of 59Fe was for 9000 seconds (live time) after
2 weeks cooling.
RESULTS: Figure1 shows the DO in the bottom water atdredged area and at an observatory (non-dredged) near
the Tokyo light beacon. Seawater above the dredged
trench had the following features: 1) vertical circulation
is weak in summer, and 2) horizontal currents are thesame as in other areas. That is, the Makuhari dredged
trench underwent a localized low DO event caused by
rapid DO consumption such as microbial respiration. It is
well-known fact that concentrations of iron and manganese in sediments have increased when condition of sea-0
1974/01/01

1984/01/01

1994/01/01

2004/01/01

date (yyyy/mm/dd)

Fig. 1. Variation in DO of bottom water mass over decades in the dredged area (full) and the Tokyo beacon(dashed).

Fig. 2. Vertical distribution of Fe (left) and Mn (right) inthe sediments. Stations OC (●) and OD (■) were locatedat dredged area, station OE (△) was located at
non-dredged area.
REFERENCES:[1] Diaz R.J., Rosenberg R., Science, 321 (2008)
926-929.
[2] Sasaki, J., Kawamoto, S., Yoshimoto Y., Ishii, M.
Kakino, J., J. Coastal Res., 56 (2009) 890-894.

採択課題番号 23075
汽水域および沿岸域堆積物の放射化分析
一般通常（東大・大学院総合）松尾基之、小豆川勝見、山形武広、小森昌史、下元類、陳品彧、添盛晃久、
田畑昇人 (京大・原子炉）高宮幸一、奥村 良

Instrumental Neutron Activation Analysis of Crystalline Schist Boulders
from the Upper Cretaceous Onogawa Group, Eastern Kyushu, Japan

T. Suzuki , K. Takamiya 1 and R. Okumura 1
Faculty of Education, Kagoshima University
Research Reactor Institute, Kyoto University

1

INTRODUCTION: Metamorphic rock of crystalline
schist ranging from boulders to pebbles have found in
the Upper Cretaceous Onogawa Group [1, 2] which isdeveloped closely with Sanbagawa metamorphic rockin eastern Kyushu, south-western Japan. However,
Isozaki and Itaya [3] used K-Ar dating to determine
the Early Jurassic ages of two boulders of these schist
clasts and suggested that the boulders were derived notfrom Sanbagawa but from Sangun metamorphic rocks.
Other while, several recent studies have insisted that
Sanbagawa metamorphic rocks are metamorphic faciesof the Lower Shimanto Group [4]. The purpose of thisstudy is to clear the chemical characteristics of
crystalline schist boulders in the Upper Cretaceous
Onogawa Group, psammitic Sanbagawa metamorphic
rock, psammitic rock of the Cretaceous Shimanto
Groups and psammitic Sangun metamorphic rock withthe rocks from Asaji, Asakura and Nagasaki innorthern Kyushu.
EXPERIMENTS: Instrumental neutron activation
analysis is a convenient and accurate method ofmultielemental analysis for a large number ofgeological samples. Neutron irradiation was carried out
using the Pn-2 facility at KUR Kyoto University
Reactor (1 MW/h) for 1–2 h. Gamma-ray spectrometry
was conducted at the Radio Isotope Laboratory of
Kagoshima University. In all, 106 irradiated samples
made from 39 rock specimens and working standardsof GSJ JB1a and JR1 were analyzed.
RESULTS: Because the analysis reported in this study
is still underway owing to the long life of the nuclides,
partial experimental results are presented here with thedata already given for the Shimanto Group as theaverage values for about 100 samples. Figure 1 shows
the relation between the abundance of La and that of
Th normalized by the Sc content. Figure 2 shows thelanthanoid pattern for the rocks analyzed. The
Sanbagawa crystalline schist boulders in this study areslightly pelitic.
From the data of the trace element abundance, theorigin of crystalline schist boulders in the Onogawa
Group remains unclear. Further investigations using
additional samples and parameters are required.

Upper Shimanto
Group
Saiki Sub-Group,
L. Shimanto G.

10.0

Kamae Sub-Group,
L. Shimanto G.

8.0

La/Sc

CO5-14

Psammitic Schist
Boulders

6.0

Asaji Metamorphic
Rocks

4.0

Sangunn
Metamorphic Rocks

2.0
0.0

AsakuraMetamorphic Rocks
0.0

1.0

2.0

3.0

Th/Sc

NagasakiMetamorphic Rocks
SanbagawaPsm.Schist

Fig.1. Relation between La/Sc and Th/Sc.

100

10

1
La Ce

Sm Eu

Tb

Yb Lu

Fig.2. Lanthanoid pattern of psammitic rocks.
Bold line: Crystalline schist boulders in the Upper Cretaceous
Onogawa Group.

REFERENCES:[1] N. Kanbe and Y. Teraoka, Geology of the Usuki
district, Geol. Surv. Japan (1968) , 40p.
[2] K. Miyazaki and T. Yoshioka, Geology of theSaganoseki district, Geol. Surv. Japan (1994) , 63p.
[3] Y. Isozaki and T. Itaya, Jour. Geol. Soc. Japan, 95(1989) 361–368.
[4] S. Otoh et al., Jour. Geogr., 119 (2010) 333–346.

採択課題番号 23077 九州白亜系大野川層群に関する INAA と FT 年代測定
（鹿児島大・教育）鈴木達郎 （京大・原子炉）高宮幸一、奥村 良

共同通常

CO5-15 Natural Analogue Study Using Trace Elements in Rock Alteration Zones
T. Honda, T. Hagiwara and S. Sekimoto1
Graduate School of Engineering, Tokyo City University
1
Research Reactor Institute, Kyoto University
INTRODUCTION:
High level radioactive waste(HLW) can remain highly radioactive for tens of thousands of years. As a method of HLW disposal, geologic
disposal has been employed in Japan. Under this method,
it is assumed that the radioactive substances included in
HLW will be contained by an artificial barrier for several
thousand years and by a natural barrier for tens of thousands of years thereafter. Some observers, however, havepointed out safety issues. In deep strata, groundwater
generally flows slowly but, in cases in which such strata
has many fractures and faults, can flow quite rapidly,
raising concern that radionuclides can leach into the environment sooner than expected. In this study, we evaluate the distribution and behavior of natural analogue elements in altered rocks. We examine the trace elements
uranium (U), thorium (Th), and the lanthanoids as natural
analogues to minor actinoids. The chemical properties ofthe lanthanoids are similar to those of minor actinoids,
such as americium (Am) and curium (Cm); by understanding the behavior of these analogues in altered rockover long periods, we should thus be able to evaluate thelikely behavior of minor actinoids under similar conditions.
EXPERIMENTAL:
Table 1. Profile of samples
Seven rock samples were collected from boreholes drilled Group Samples Lithofacies
TGP1-1-1
Parentunder the direction of researchTGP1-1-2
Parenters from the Tono Geosciences TG1 TGP1-2 Parent
TGP1-3
ParentCenter of the Japan Atomic EnTGP1-4
Parentergy Agency. Sample examinaTGA2-1 Alteration
Alteration
tion, primarily macroscopic ob- TG2 TGA2-2
TGA2-3 Alteration
servation, centered on feldspar
TGP3-1
Parentand biotite alteration zones. TG3 TGP3-2 Parent
TGP3-3
ParentNon-alteration and alteration
TGP4-1
ParentTG4
TGP4-2
Parentzones were identified in this
Alterationmanner (Table 1). Trace ele- TG5 TGA5-1
TGA5-2 Alteration
ments, namely, U, Th, and the TG6 TGA6-1 Alteration
TGA6-2 Alteration
lanthanoids, were measured byneutron activation analysis (NAA) of pulverized samples.
Neutron irradiation was performed at the Kyoto University Research Reactor (KUR; Table 2).
Table 2. Irradiation conditions at KUR
Half-life

Irradiation
facility

long
short

PN-2
PN-3

Output(MW)
1

Max thermal
neutron flux
(n/cm2・s)

Irradiationtime

5.5×1012
4.68×1012

4h
40sec.

RESULTS: Similar results were obtained for all samples
except for those in the TG2 group. Light lanthanoids(lanthanum (La) to europium (Eu)) were found to be in-corporated into mainly silicate minerals but also incorporated to some degree into oxide or carbonate minerals.
Heavy lanthanoids (gadolinium (Gd) and lutetium (Lu))
were found to be incorporated into mainly silicate minerals but also partly into oxide etc.. U and Th were foundto behave similarly to the heavy lanthanoids. As for the
TG2 group samples, it is thought that light lanthanoids
are incorporated into mainly oxide (and into sulfide andphosphate minerals in the case of TGA2-2 only), withsome slight incorporation into carbonate minerals. Heavylanthanoids were found to be incorporated into mainly
silicate minerals. However, the abundance of heavy lanthanoids in silicates was lower than that in the parent
rock, and the abundance in other minerals (oxide, carbonate minerals) increased. U and Th were found to behave similarly to the heavy lanthanoids.
From the above, in the alteration zones, the abundance oflanthanoids is lower in silicates than in other minerals.
Therefore, it is possible that lanthanoids precipitated in
the alteration zone upon an infusion of lanthanoidbearing groundwater.
We next consider the behavior of minor actinoids in lightof the above findings regarding their natural analogues.
Lanthanoids were found to be contained in clay and carbonate minerals formed by alteration. Clay has a layered
structure; and, as each layer is negatively charged, cations
are thus drawn to them. Many radioactive substances(Am, Cm, etc.) are positively charged. It has been reported that radioactive substances are incorporated into
clay through ion exchange. Indeed, we find that lightlanthanoids had been incorporated into clay within thealteration zones. Because the ionic radii of light lanthanoids (98 to 122 pm) are similar to those of Am and Cm(107 and 99 pm), we infer that those two elements arealso readily incorporated. In addition, it has been reported
that light lanthanoids are also readily incorporated into
carbonate minerals because the ionic radii of those elements are similar to that of the carbonate constituent Ca2+
(106 pm)1). This is consistent with our finding that lightlanthanoids are incorporated into the carbonate minerals
within both the alteration zones and the parent rock. Because light lanthanoids are readily incorporated into carbonate minerals, we infer that Am and Cm are likewise
readily incorporated into those minerals. We also foundthat light lanthanoids are incorporated into oxide andphosphate minerals, leading us to infer that Am and Cm
are also incorporated into oxide and phosphate minerals.
We also found that many light lanthanoids accumulate inalteration zones. From this we infer that Am and Cm
similarly accumulate in alteration zones.
REFERENCES:[1] R. Dobashi et al., Geochemistry, 42 (2008)79.

採択課題番号23080 岩石変質部における微量元素を対象としたナチュラルアナログ研究(都市大院・工)本多照幸、萩原武司 (京大・原子炉)関本 俊

共同通常

Comparison of Determination Accuracy of NAA in KUR and JRR-3

Graduate School of Science, Kyoto University
S.H.I. Examination & Inspection, LTD.
1
Research Reactor Institute, Kyoto University
INTRODUCTION: Neutron Activation Analysis (NAA)
in Japan has been performed mainly at KUR of Kyoto
University Research Reactor Institute and JRR-3 of Japan
Atomic Energy Agency. However, a comparison between
sensitivities in performing NAA with KUR and that with
JRR-3 had not been discussed. Then we carried out comparison experiments for stabilities of neutron flux andneutron spectrum. And examinations of determining thestandard material of NIST SRM 1633b were performedby k0-NAA between KUR and JRR-3 for an analysis of
air particulate matter [1].
EXPERIMENTS: Gold standard foils were irradiatedfor 3 minutes at Pn-3 to evaluate neutron flux deviationby every 10 min. And Au and Zr standard foils were irradiated together for 5 minutes at Pn-3 for evaluate neutronenergy spectrum. About 1 day after irradiation, the Au
and Zr standards were measured for 150 and 5000 seconds, respectively. The neutron flux deviation of Pn-3
were evaluated from activity of Au standards, and neutron energy spectrum were evaluated from the value of f(rate of thermal/epithermal neutron fluxes) and  (deviation of neutron energy spectrum from 1/E) calculated bytriple monitor method. NIST SRM1633b was irradiatedfor 1 minute by Pn-3 (1MW) for measurements of short
lived nuclides, and 40 minutes by Pn-2 (5MW) for measurements of long lived nuclides. Interference correction
from nuclear reaction of 27Al(n, p)27Mg, 27Al(n, )24Na,
and 56Fe(n, p)56Mn were carried out using results obtained by irradiation experiments for pure Al and Fe
samples.

lar, but the neutron energy spectrum at Pn-3 of KUR was
more unstable than that at PN-3 of JRR-3. And differences between determined values and certified values of
NIST SRM1633b are within 10% for 20 elements. Although energy spectrum was unstable in comparison with
JRR-3, qualitative analysis by k0-NAA method using
KUR is available.

Neutron flux deviation from average

S. Miyata, Y. Matsumoto, H. Sakane, K. Takamiya1
and R. Okumura

1.2
1.1
1
0.9
0.8
15:30

16:00

16:30

17:00

17:30

18:00

(a)
Neutron flux deviation from average

CO5-16

1.2
1.1
1
0.9
0.8
9:30

10:30 11:30 12:30 13:30 14:30 15:30 16:30(b)Fig. 1. Neutron flux deviation from average
about KUR(a) and JRR-3(b).

30%
20%
10%

RESULTS: The relative standard deviations of neutron
fluxes at Pn-3 KUR are 1.5% (Fig. 1a) and 1.8% at PN-3
in JRR-3 (Fig. 1b), which means neutron flux deviation at
Pn-3 of KUR is similar level as PN-3 of JRR-3. The deviations of f and  values are 22% and 166% in KUR,
respectively. In JRR-3, f deviation is 6.4%. It shows thatthe neutron energy spectrum at Pn-3 of KUR is moreunstable than that at PN-3 of JRR-3. Difference between
determined values and certified values of NIST
SRM1633b was within 10% in 20 elements (Fig.2)
CONCLUSION: The stabilities of neutron fluxes atneutron irradiating position of KUR and JRR-3 are simi-

0%
-10%
-20%
-30%

Na Al K Ca Ti V Mn Ga As Ba Na K Sc Cr Fe Co Zn As Sb Cs Ce Eu W Hf Th
Na

Al

K

Ca

Ti

V

Short life

Mn

Ga

As

Ba

Na

K

Sc

Cr

Fe

Co

Zn

As

Sb

Cs

Ce

Eu

W

Hf

Th

Long life

Fig. 2. Deviation of analytical results from certified value.

REFERENCES:[1] S. Miyata et al., Bunseki kagaku, 689 (2006)

採択課題番号 23081 ＫＵＲとＪＲＲ－３による放射化分析法による定量精度の比較（住重試験検査）宮田賢、松本洋平、坂根仁（京大・原子炉）高宮幸一、奥村良共同通常

CO5-17

Geochemical Mapping for the Upper Ara-river System Area,
Saitama Prefecture by Neutron Activation Analysis

T. Fukuoka, Y. Saito1, M. Ishimoto2 and H. Kusuno

Fieldwork to collect samples

Faculty of Geo-environmental Science, Rissho University
1
College of Science and Engineering, Aoyama Gakuin
University
2
School of Engineering, The University of Tokyo

Dehydration of samples
at room temperature
110℃
900℃

INTRODUCTION: Geochemical maps can express
areal distributions of chemical elements in the earth’s
land surface and give information about the chemical
background in the natural environment to assess the artificial environmental changes [1, 2]. In this study, we report the geochemical mapping for the upper Ara-river
system, Chichibu Mountains area, Saitama in 2011.
Cosmo-Geochemistry Lab., Rissho University has been
making up the geochemical maps since 2000.
EXPERIMENTS: We analyzed the stream sediments
which had been collected as a sample representing thegeochemical characters in each drainage basin. A sampling site 1 per 1 km2 was selected in the area which a
mountain ridge was surrounding and at 100m upperstream in the branch from the junction of main stream to
avoid the contamination by floods. The stream sediment
was sieved to 80 mesh (<180 ㎛) on site and the fine
fraction was reserved for analysis. 47 elements in collected samples are analyzed by X-ray Fluorescence
Analysis (XRF), Laser Ablation Inductively Coupled
Plasma Mass Spectrometry (LA-ICP-MS), Prompt
Gamma-ray Analysis (PGA) and Instrumental Neutron
Activation Analysis (INAA) (Fig. 1 and 2). INAA has
great advantage for Au, As and Sb analyses comparedwith ICP-MS, because of their high ionization potential.
RESULTS: Figure 3 indicates as an example of geochemical map of Au resulted from this study. In previous
studies of geochemical map of this area, western area
indicate highest contents of Au, As and Sb. The geochemical maps of As and Sb indicate similar distributionof these elements and similar to Au. Gold mine was operated formerly in this area.
In this study, we found new high Au content point (No.
1121 point in Fig.3). In this sampling point, Au content issurprisingly high, but As and Sb contents are normal. So,
we have to clear the reason why it doesn’t agree with
geochemical behavior of three elements, in No. 1121
sampling point. Possible answer is analytical contamination. Because recently Au distributes widely in our living
environment such as cosmetics, electrical connector etc.

1.3g

XRF
LA-ICP-MS

Fig. 1

0.7 g

PGA

Flowchart of analytical procedure.

Fig. 2 Elements analyzed by XRF, LA-ICP-MS, PGA
and INAA.

Fig. 3 The gold geochemical map of the upper-Ara
River System.

REFERENCES:[1] Darnley, A. G. et al. (1995) 19, UNESCO Publishing,Paris.K.
[2] Johnson, C. C., Brown, S. E. and Lister, T. R.

(2003) Initernal Report, IR/03/096N. British
Geological Survey, Keyworth, Nottingham.

採択課題番号 23083
中性子放射化分析による地球化学図の作成
一般通常（立正大・地球）福岡孝昭、楠野葉瑠香（青山学院大・理工）齋藤裕子、（東大院・工）石本光憲