CO5-1

Central Diameters and Concentrations of Element in the
Atmospheric Aerosols at Sakai,Osaka

From relations between the d50 and elemental
concentrations we have found that Zn, V, Br, Mo,Sb,As
Radiation Research Center, Osaka Prefecture University, have fine d50 (<=2.5μm) those are Zn(0.9～1.8μm),
1Research Reactor Institute, Kyoto University
V(0.28～0.48μm), Br(0.34～0.59μm), Mo(0.24～1.1μm),
Sb(0.957～0.94μm), As(0.53～1.5μm).
Central diameters and concentrations of
Al,Na,Fe,Ca,Ti,Ba,Cr,Ce,Co,Th,Hf,Eu have coarse
elements(Na,Al,Cl,K,Ca,Ti,V,Cr,Mn,Fe,Co,Ni,Zn,As,Br, d50(>=2.5μm) those are Al(4.6～6.0μm), Na(3.7～4.3μm),
Fe(3.5～5.1μm), Ca(4.7～6.2μm), Ti(4.0～5.9μm), Ba(2.2
Rb,Mo,Sb,Cs,Ba,La,Ce,Sm,Eu,Hf,W and Th) in the～4.1μm), Cr(2.6～4.9μm), Ce(3.0～4.7μm),Co(2.4～
atmospheric aerosols collected at Sakai, Osaka in 2012
have been obtained. We have collected aerosols separated 4.6μm), Th(4.0～6.2μm), Hf(4.5～5.4μm),Eu(4.4～by the 9 diameter ranges(<0.43,0.43～0.65,0.65～1.1,1.1～ 5.6μm),. Cl,K,Mo,Ni,W, La,Cs have coarse and fine d50
2.1,2.1～3.3,3.3～4.7,4.7～7.0,7.0～11,>11μm) using
depending on the sampling period. The variation causechanges of the main constituents in fine d50 depending onAndersen sampler on one week periods (P1:Feb.14-21,
P2:Apr.03-10, P3:Jun05-12, P4:Aug.07-14, P5:Oct.09-16, the sampling period like that, K, Zn,Mn on P1 , Zn on P2 ,P6Dec.11-18: in 2012).To collect the samples completely K ,Zn on P3, Zn on P4, K, Zn on P5, Cl,K,Zn on P6 .
and reduce an affect of contamination we have put
In the fine d50 elements ordered by high to lowpolyethylene sheet(80mmΦ, ～1mg/cm2) on the each stage concentration are Cl,K,Zn,Mn,V,Br,Ni,Mo,Sb,As, W, La ofof the sampler.
which order changes on the sampling period.
The element concentrations were analyzed by neutron
activation analysis using Kyoto University Nuclear Reactor
on following irradiation conditions ( In Pn1 120sec for
Al,Cl,Ca,V,Mn, In Pn2 30min for Co, Ni, Zn, As,Br, Rb,
Mo,Sb,Cs,Ba,La,Ce,Sm,Eu,Hf,W,Th).Gamma ray
spectrum from each irradiated samples were measured by
Ge-Solid state detector and 4096channel multiple pulse
height analyzer. The measuring time(2000～20000sec) andstarts of measurements are determined by the gamma rayintensity of each sample.
From the concentration results in each particle diameter
range we have determined the central diameter(d50) which
is a diameter of 50% accumulation concentration summingby the each particle diameter range concentration(Fig.1).
From the concentrations in each diameter range we get ascatter graph of d50 and total concentrations of eachelement on 6 sampling periods(Fig.2).
N.Ito, A.Mizohata , R Okumura1 and Y Iimura
Iinuma11

Fig.2 Scatter graph of d50 and total
concentrations for each elements in theaerosols collected 2012 at Sakai.

Fig.1 Example of accumulation curve and central
diameter(d50) on concentrations of K(Feb14-21 2012)by aerosol diameter in 9 size ranges.

採択課題番号 26011
大気エアロゾル粒子のキャラクタリゼーション( 大阪府大地域連携 ) 伊藤憲男、溝畑 朗 ( 京大原子炉 ) 奥村良、飯村勇人
奥村良、飯沼勇人
116

通常採択
共同通常

CO5-2

Study of Earth and Planetary Matters by Thermoluminescence
The induced TL of unequilibrated ordinary chondrites
has been usually measured above room temperature.
Then this time low temperature TL (-150~ 0 oC) were
investigated to distinguish TL properties between primitive chondrites and secondary altered chondrites. TL
glow curves of a primitive ordinary chondrite ofA881244 (L3.0) and remarkable shocked chondrite ofA8811255 is shown in Fig.1. TL glow curves of a primitive ordinary chondrite of A881357 (L or LL 3.3-3.4) anda moderate shocked chondrite of A880708. There are two
peaks near -120 and -80oC lower than room temperature.
However we could not find clear difference in TL propertied between primitive chondrites and secondary alteredchondrites.

K. Ninagawa, H. Nishido and S. Hamada
Okayama University of Science
LOW TEMPERATURE TL OF ORDINARY
CHONDRITES: Induced TL (thermoluminescence), theresponse of a luminescent phosphor to a laboratory doseof radiation, reflects the mineralogy and structure of thephosphor, and provides valuable information on themetamorphic and thermal history of meteorites. Thermal
metamorphism causes the production of feldspar, themajor TL phosphor in ordinary chondrites, by the devitrification of feldspathic mesostasis. Primitive chondrites of
petrologic subtype ≦ 3.4 with coefficient of variations( as a percentage of the mean) over 50%, of fayalite in
the olivine have low TL sensitivities under 0.1. The sensitivity of the induced TL is usually used to determine
petrologic subtype of unequilibrated ordinary chondrites[1]. On the other hand, TL sensitivity decreases 10-foldafter shock-loading to 25-32 GPa [2], and terrestrial
weathering makes TL sensitivity decrease 16-fold at
maximum in Antarctic chondrites [3]. Then some secondary altered chondrites were reported to have low TL
sensitivities, equivalent to primitive chondrites [4].

LOW TEMPERATURE TL OF UREILITE: The
ureilites are a major group of primitive achondrites. They
are high fractionated rocks from an achondrite parent
body. Ureirites are olivine-pyroxene rocks with interstitial C (graphite and microdiamonds) mixed with metal,
sulfides, and minor silicate. Most ureilites are essentiallydevoid of feldspar [6]. This time we measured induced
TL of five ureilites to check TL properties of ureilites.
Fig.3 shows TL glow curve of Dar al Gani 319 andNWA3223. There were two large peaks at -100 and 0oC.
Ureilite

A881244 (L3.0)
A881125 remarkable shocked

700

12000
TL Intensity (cps)

TL Intensity (cps)

600
500
400
300
200

-100

-50

0

50

100

150

200

250

300

6000
4000

A880708 moderate shocked

3500
3000
2500
2000
1500
1000
500
0

50

100

150

200

250

300

350

Temperature (oC)Fig.2. TL glow curves of A881357 and moderate shockedchondrite of A880708. The different peaks at 50 and 150
o
C reflected to disordering of feldspar.

採択課題番号 26024

0

50

100

150

200

250

300

350

REFERENCES:[1] Sears et al., Proceedings of Lunar and Planetary Science 21 (1991) 493-512.
[2] Hartmetz et al., Proc. 17th Lunar Planet. Sci. Conf. (J.
Geophysical Research), 91, (1986) E263-E274.
[3] Benoit and Sears, J. Geophys. Res., 104, (1999)
14159-14168.
[4] K. Ninagawa et al., Antarctic Meteorite Research, 15(2002) 114-121.
[5] K. Ninagawa et al., Antarctic Meteorite Research 18(2005) 1-16.
[6] Weisberg et al. Meteorites and the early solar System
II, The University of Arizona Press, (2006) 19-52.

A881357 (L or LL3.3-3.4)

-50

-50

Fig.3. TL glow curve of ureilites, Dar al Gani 319 andNWA3223.

4000

-100

-100

Temperature (oC)Fig.1. TL glow curves of a primitive ordinary chondriteof A881244 (L3.0) and remarkable shocked chondrite ofA8811255.

TL Intensity (cps)

8000

0
-150

350

Temperature (oC)0-150

NWA 3223

10000

2000

100
0
-150

Dar al Gani 319

14000

800

熱ルミネッセンスによる地球惑星物質の研究（岡山理大）蜷川清隆，西戸裕嗣，濱田聖矢

117

通常採択

CO5-3

Evaluation of Redox Conditions at Dredged Trenches in Tokyo Bay
by the Concentrations of Elements in the Sediments

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

trations of Fe and Mn in sediments were almost constantfrom the surface to the lower layers. It is well-known factthat the concentrations of Fe and Mn in sediments decrease due to eluviations of Fe2+ and Mn2+ when condition of seawater is reductive like hypoxia. The results
indicate that the redox conditions of the surface of sediments were not so reductive as those in August 2011 [4].
On the other hand, we calculated Th/U and Ce/U ratios
likewise Honda et al [5], and the depth profiles of theratios in sediment are shown in Figure. The Th/U andCe/U ratios in the upper layers (7-8 cm from the surface)were comparatively high, and the ratios settled down toalmost constant lower values below 8 cm in depth at mostsites. It is known that the concentrations of Th and Ce in
sediments increase when condition of seawater is oxidative, and the concentration of U increases when conditionof seawater is reductive. It is considered that the sedimentary environment of the upper layers is more oxidative than that of the lower layers. And focusing on theredox potential around U(VI)/U(IV), the method using
Th/U and Ce/U ratios is well reflecting the redox states,
because those of U, Th, Ce are thought to be preserved
from the time of sedimentation.
As mentioned above, the method measuring the concentrations of various elements by INAA and focusing on
different redox potentials of the elements is very useful toevaluate the sedimentary environment related to redox
conditions.

Graduate School of Arts and Sciences, The Univ. of Tokyo
1
Research Reactor Institute, Kyoto University
INTRODUCTION: Hypoxia is water mass with little dissolved oxygen (DO) [1]. In Tokyo Bay there aremany large and deep dredged trenches, especially off thecoast of Makuhari, Chiba. In dredged trenches severe
hypoxia has been observed in summer, but the influenceof dredged trenches on hypoxia is not revealed yet.
Therefore, it is important to estimate the positional andseasonal variations of hypoxia by analyzing sediments.
To estimate the sedimentary environment related toredox conditions, various elements have been used. For
example, Fe and Mn are used because their various
chemical states on Eh-pH diagrams have become clear[2]. And U is used for the evaluation of weak reductive
conditions because the redox potential of U(VI)/U(IV) is
between Mn(IV)/Mn(II) and S(VI)/S(-II) [3]. We haveapplied the elements to evaluate the sedimentary environment in dredged trenches, which are under specificcondition. In this study, sediment cores were collectedfrom the Makuhari dredged trenches and concentrationsof Fe, Mn, U, Th, and Ce in sediments were analyzed byinstrumental neutron activation analysis (INAA).
EXPERIMENTS: The sediment samples were collected at a dredged trench (water depth 17.2 m) and reference site (non-dredged seabed, water depth 9.5 m) off
the coast of Makuhari in Tokyo Bay in August 2013.
Sediments were collected by a core sampler and water
quality data were also obtained.
All cores were cut in the vertical direction at 0.6-3.0
cm intervals in the laboratory, and the samples were desalted and freeze-dried within a week.
Approximately 30 mg of sediments were packed indouble polyethylene film bags to perform INAA. All
samples were irradiated with neutrons at the pneumatictube, Kyoto University Research Reactor. Three types ofgamma-ray measurement were carried out corresponding
to half-lives of elements. For analysis of Mn, samples
were irradiated for 10 seconds at 1 MW, and then gamma-ray was measured for 600 seconds by Ge detector
after 600 seconds cooling. Regarding U, samples were
irradiated for 20 minutes at 1 MW or 4 minutes at 5 MW,
and then gamma-ray was measured for 1200 seconds by
Ge detector after 3-5 days cooling. Regarding Th and Ce,
samples were irradiated for 20 minutes at 1 MW or 4
minutes at 5 MW, and the measuring time of gamma-ray
was for 9000 seconds after 2-4 weeks cooling.
RESULTS: At the dredged trench surface water (< 9m water depth) had DO about 6 mg/L, and bottom water(> 12 m water depth) had no DO. At both sites, concen-

Figure. Depth profiles of Th/U (left) and Ce/U
(right) ratios in the sediments collected from Tokyo
Bay in August 2013.
REFERENCES:[1] R.J. Diaz et al., Science, 321 (2008), 926-929.
[2] D.G. Brookins, in Eh-ph diagrams for geochemistry(Springer-Verlag, 1988).
[3] D.R. Turner et al., Geochim. Cosmochim. Acta, 45(1981), 855-881.
[4] T. Yamagata et al., J. Radioanal. Nucl. Chem., 303(2015), 1179.
[5] T. Honda et al., Bull. Soc. Sea Water Sci., Japan, 57(2003), 166-180 (in Japanese).

採択課題番号 26028
汽水域および沿岸域堆積物の放射化分析
通常採択（東大・大学院総合）松尾基之、小豆川勝見、山形武広、堀まゆみ、青木隆太朗、渡邊利奈、徐放、
山本駿（京大・原子炉）高宮幸一、奥村良118

CO5-4Characteristics of Synthetic Calcite Thermoluminescence Studied for
Paleoenvironmental Reconstruction of East Asia

N. Hasebe, K. Ito, K., K. Miura1 and M. Ogata1

tration to emit luminescence. The TLCI with small
amount of Fe show colored pixels. However, these pixels may be noises because they are found in all colorzones. Mg added samples emitted no luminescence.
Therefore, Mg would not play significant role in luminescence characteristics.

Institute of Nature and Environmental Technology, Kanazawa University
1
Graduate School of Natural Science and Technology,
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. Thermally stimulated
luminescence from calcite shows strong red emission [1].
However, thermoluminescence dating of calcite is lesspopular because of some unknown problems; e.g., sensitivity change of calcite occurred through repeated heatingof samples, possible anomalous fading, difference incharacteristics of luminescence response against different
kinds of radiation (e.g., gamma-ray, beta-ray, alpha-ray,and X-ray). When thermoluminescence characteristics
of calcites are examined using natural occurring calcite,
their response to the various radiations depends on minor
chemistry (Fe, Mg, Mn and Sr). In this study, calciteswith controlled impurity concentrations were synthesized and analyzed to evaluate relationship between multiple impurity concentration and thermoluminescence properties quantitatively.

Fig. 1. The amount of elements measured by
LA-ICP-MS is proportional to the amount of added
elements

EXPERIMENTS: Calcite were synthesized from sodium carbonate (>99.8wt%) and calcium chloride (>95wt%). Iron (II) chloride (>99.0-102.0 wt%), magnesium
chloride (>98.0wt%), and manganese chloride (>99.0wt%) were added at different levels to produce calciteswith different amount of impurity. Chemical compositionof resultant calcite were measured by LA-ICP-MS.
Gamma irradiation was carried out at the 60Co gamma
irradiation facility at Kyoto University Research Reactor.
Then luminescence images were captured by the digital
camera (Inagaki et al., 2010) and luminesce color andintensity were analyzed (Ogata et al., 2014).

$                    
#!"

RESULTS: Except for added elements, all of synthetic
calcite contain ~30 ppm of strontium and ~6 ppm of barium. These elements must be contained in original reagent calcium chloride. Mn-added calcites include molybdenum which amount is proportional to the amount ofadded Mn. Mo must be contaminated to the reagent
manganese chloride. As shown in Fig. 1, measured
amount of impurity is proportional to the amount ofadded impurity.
When thermoluminescence color image (TLCI) was captured, Mn added samples emitted strong red luminescence (Table 1). A sample with high impurity emit noluminescence. There may be some criteria in Mn concen-

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



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

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

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

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Table 1. The results of TLCI investigation. Number of pixels in each color zone is counted. R stands
for red, Y for yellow, G for green, B for blue, andgap for other color.
REFERENCES:[1] A. Inagaki et al., J. Geol Soc. Japan 116 (2010)
XIX-XX[2] M. Ogata, Sci. Rep. Kanazawa Univ. 58 (2014) 1-12

採択課題番号 26029	
  東アジアにおける古環境推定のための放射年代測定	 （金沢大・環日本海域セ）長谷部徳子、伊藤健太郎、(金沢大院・自然)三浦知督、小形学	
 
	
 

119

通常採択	
 

CO5-5 Fission Track Ages of Sedimentary Rocks from Accretionary Belt in the Kii Peninsula
H. Ohira and A. Takasu

with that the “Yanase Fault” is important thrust system
which dividing complexes of this area and the Hanazono
complex was exposed to relatively higher temperature
due to deep burial. Almost FT grain ages from the Yukawa complex show entirely older than the estimated depositional period, indicating that sample was not affectedby heating up to enough temperature to reset FT ages. On
the contrary, the youngest age component in the Ryujin
complex (59Ma) is significantly younger than the limit ofdepositional period (68-78Ma). This result probably indicates that most of FT grain ages of Ryujin complex
were reset by thermal affect during burial process to a
deeper level, or the depositional age of the Ryujin complex is actually younger than previous interpretation.
Detail track length measurement will be required for thesolution of above discussion.

Department of Geoscience, Shimane University
INTRODUCTION: Fission track dating was applied for
sedimentary rocks of Kii peninsula, Wakayama prefecture. The aim of this study is to estimate depositional
periods and thermal histories of sedimentary rocks inrelation with burial-uplift processes during accretion
process. In recent study, the Cretaceous Shimanto Belt inthis area is newly divided into several accretionary complexes showing zonal structure, Ryujin, Miyama, Yukawa and Hanazono complexes, from the south to north[1]. FT age variations across the Shimanto belt in the Kii
region and relationship between FT ages and thermal andburial/uplift history has been precisely discussed mainly
for areas of the north side including a part of Hanazono
complex [2].
EXPERIMENTS: Samples collected from each units of
the Shimanto belt were crashed and sieved and heavy
minerals were concentrated by common method. Zircon
and apatite were abundant in almost samples but lessamounts in the Miyama complex. Zircons were mounted
in PFA Teflon, and then polished to reveal entire internalsurface. Samples were etched in a NaOH-KOH eutectic
melt at 225˚C [3] for 20-32 hours and were irradiated atpneumatic tube of graphite facility (Tc-pn) of Kyoto
University Reactor (KUR). FT densities were measured
using optical microscope at 1000× magnification with adry objective 100×．FT ages were calculated by trackkey
program [4].
RESULTS: Fission track grain ages show wide variations in each sample but the youngest modes in histograms show a systematical tendency from south to north,probably corresponding to depositional period and thermal histories during burial-uplift process of each geological unit. Ranges and modes in histograms for each complexes are as follows; Ryujin (53-92Ma; 60Ma), Miyama(57-197Ma; 68Ma), Yukawa (94-300Ma; 126Ma), andHanazono (55-93; 68Ma). FT ages become old fromsouthernmost Ryujin complex toward the northern Yukawa complex, but the Hanazono complex in northernmost district show young age again. The gap of age between the Yukawa and Hanazono complex and rejuvenation of FT age in the Hanazono complex is compatible

Fig.1 FT age histogram and geological map with each complex
boundary [5].

[1] Suzuki H. and Nakaya S., 2012, The Assoc. Geological Collaboration in Japan, Monograph 59, 273-282(in Japanese with English abstract).
[2] Hasebe N. and Tagami T., 2001, Tectonophysics 331,247-267.
[3] Gleadow A.J.W. et al., 1976, Earth and Planetary
Science Letter, 33, 273-276.
[4] Dunkle, I., 2002, Computer & Geosciences, 28, 3-12.
[5] Suzuki H., 2012, The Assoc. Geological Collaboration in Japan, Monograph 59, 101-110 (in Japanesewith English abstract)

採択課題番号 26036 フィッション・トラック年代測定法による岩石の熱履歴解明に関する研究 通常採択
（島根大・総合理工）大平寛人，高須 晃
120CO5-6 Trace Amounts of Halogens (Cl, Br and I) in Manganese Nodule Reference Materials
M. Ebihara and S. Sekimoto1

Our RNAA data for Nod-P-1 and Nod-A-1 are not consistent with the literature data obtained by ICP-SFMS for
both bromine and iodine. As for iodine the ICP-SFMS
values are lower than the RNAA values. Such an inconsistency between RNAA values and ICP-SFMS values
also may be derived from the loss of iodine in the aciddigestion procedure with heating by the microwave. To
prevent the loss of iodine, the digestion solution should
not be heated in principle, or heating of the digestion solution must be achieved with extreme care. Regarding
bromine, on the other hand, the ICP-SFMS values arehigher than the RNAA values by a factor of about three tofive. Such an inconsistency between RNAA values and
ICP-SFMS values may be due to the ability of thisICP-SFMS instrument, especially to background [4].
Bromine is determined by ICP-SFMS and/or ICPMS
using the isotope 79Br and 81Br. The mass of those twobromine isotopes is next and very close to the biatomic(40Ar40Ar)+ molecule of mass 80. Since argon is so abundant in the plasma of the ICP-SFMS and/or ICPMS, thecombination of two 40Ar ions causes a large peak at mass
80 whose peak tail could interfere with either stable isotope of bromine. Additionally, there are several potential
interferences on 79Br and 81Br; (40Ar39K)+, (63Cu16O)+ and(40Ar38Ar1H)+ interference with 79Br and (40Ar41K)+,(65Cu16O)+ interference with 81Br signals, respectively [4].
To quantify 79Br successfully without interference of(40Ar39K)+ and (63Cu16O)+ nor of (40Ar38Ar1H)+, the
ICP-SFMS instrument should be operated in resolution(m/m) of >10000 or >5000, respectively. (A required
resolution for successful quantification of 79Br is explained in the Supporting Information.) In case of theliterature values for bromine, however, the ICP-SFMS
instrument was operated in medium resolution mode(m/m=4500) for 79Br, and interference of (40Ar39K)+ and(63Cu16O)+ cannot be removed from 79Br signal. A possible explanation of higher bromine values in ICP-SFMS
than in RNAA could be an overestimation due to the interference at mass 79 in the ICP-SFMS instrument. Since
the ICP-SFMS operation in high resolution mode (HRM)
is generally the operation in resolution (m/m) of
9000-10000, it is fundamentally impossible to quantify
79
Br successfully without interference of (40Ar39K)+ and63( Cu16O)+ even using the HRM. This suggests that bromine-separation as a pretreatment of samples is essential
for bromine-determination using ICP-SFMS and/or
ICPMS.

Graduate School of Science, Tokyo Metropolitan University
1
Research Reactor Institute, Kyoto University
INTRODUCTION: Accurate and reliable data of halogen abundance have been rarely reported for terrestrial
samples, such as manganese nodule materials. Since halogens differ in volatility from element to element, theircontent and relative abundance are highly informative
when discussing the petrogenesis of such samples. Recently, we have improved the radiochemical neutron activation analysis (RNAA) procedure for trace amounts of
halogens (Cl, Br and I) [1]. In this study, our RNAA wasapplied to two manganese nodule materials that areavailable in U.S. Geological Survey (USGS) and then,our RNAA values were compared with the literature values.
EXPERIMENTS: Trace amounts of Cl, Br and I in thetwo manganese nodules (Nod-P-1 and Nod-A-1) were
determined by RNAA. The RNAA procedure is described
elsewhere [1-2]. Those samples were repeatedly analyzed
more than two times.
RESULTS: The two manganese nodules (Nod-P-1 andNod-A-1) analyzed using RNAA in this study were also
analyzed using inductively coupled plasma double focusing sector field mass spectrometry (ICP-SFMS) [3]for bromine and iodine. Our RNAA values and the
ICP-SFMS values are shown in Table 1. Before analysis
by ICP-SFMS, the nodule materials were subjected to theacid digestion procedure, in which the nodule materials
are heated with the mixture of concentrated nitric, hydrochloric and hydrofluoric acids by using microwave.
The digestion solution was diluted appropriately and thenintroduced into the ICP-SFMS instrument.
Table 1: Cl, Br and I contents in USGS manganese nodule materials analyzed by RNAA in this studya and fromthe LiteraturesampleNod-P-1

Nod-A-1a

RNAA(n = 4)
ICPSFMS15RNAA(n = 2)ICPSFMS15

Cl(mg kg-1)
1380 ± 140

Br(mg kg-1)
5.93 ± 0.76

I(mg kg-1)
157 ± 17-b30.3 ± 2.2

31.4 ± 0.3

4410 ± 160

14.8 ± 0.5

367 ± 9b40.9 ± 0.7

47.7 ± 3.2-

REFERENCES:[1] S. Sekimoto and M. Ebihara, Anal. Chem., 85 (2013)
63366341.
[2] S. Sekimoto and M. Ebihara, in preparation.
[3] M.D. Axelsson et al., Analyst, 127 (2002) 76-82.
[4] J. Hammerli et al., Chem. Geol., 337-338 (2013)75-87.

Mean values followed by standard deviations (1) (n=3,4). Mean values followed by an uncertainty which issimply the value calculated from two individual uncertainty values. (n=2) bNot reported.

採択課題番号 26043

宇宙・地球化学試料中の微量ハロゲン(Cl, Br. I)の中性子放射化分析（首都大学東京・大学院・理工）海老原 充、白井直樹（京大・原子炉）関本 俊
121

通常採択

CO5-7

Application of Neutron Activation Analysis to Micro Gram Scale of Solid Samples

S. Sekimoto, N. Shirai1, M. Ebihara1

using Allende and JB-1 as reference samples. Hereafter,these experimental runs named run-2 [1] and run-3 [2]are discussed in comparison with the present study, whichis named run-1. It is meaningful to compare the activityof radioactive nuclides used in INAA for two different
reference samples. We discuss the gamma rays counting
rate per unit mass for each target element, hereafter
gamma-ray intensity, among three runs. The gamma rays
counting rate is gamma ray counts per second and correspond to gamma ray energies designated for individual
nuclides (24Na, 46Sc, 59Fe, 140La, 153Sm, 58Co, 60Co, 65Zn
and 51Cr). Those nine nuclides were determined both forAllende and JB-1. Relative gamma-ray intensities of 24Na,
46
Sc and 59Fe in both reference samples are highly consistent for the three runs. Such a consistency can also beseen for Fe reagents. Kong and Ebihara [3] evaluated theconsistency in elemental contents in the mg size of JB-1
and confirmed that JB-1 is well homogenized for its use
in mg. We confirm that Allende can also be used as areference sample for mg scale of sample at least for Na,
Sc and Fe. On the other hand, Allende and JB-1 show asmall inconsistency, most of which may be due to poor
counting statistics for either sample. For example, Allende tends to have relatively low contents of rare earth elements (La and Sm), whereas JB-1 has a low content of
Ni and Zn. Depending upon elemental contents, either
Allende or JB-1 may be used for a reference sample.
There appears an apparent inconsistency in Cr data between the two reference samples, with JB-1 having systematically higher gamma-ray intensity. This isundoubtfully due to an erroneous reference value (425
mg kg-1) of Cr for JB-1. If a proposed value (475 mg
kg-1) [3] is instead used, an excellent consistency can beseen as shown in Fig. 1 for 51Cr.

Research Reactor Institute, Kyoto University
1
Graduate School of Science, Tokyo Metropolitan University
INTRODUCTION: Since instrumental neutron activation analysis (INAA) is a non-destructive and multi-elemental analysis method, it is suitable for precious
samples and, especially, for such specimens as thosehighly desired to be neither physically decomposed nor
chemically dissolved. Meteorites are the best example forsuch samples. Chondritic meteorites (chondrites) and ironmeteorites contain relatively high contents of Co and Ir
compared with those in the earth crust. As Co and Ir havehigh sensitivity in NAA, they can be good markers forthe identification of such extraterrestrial materials. In
NAA of chondrites, a few tens mg of specimen is commonly used. For such a case, a few hundred μg kg -1 of Ir
and a few hundred mg kg-1 of Co can be reliably determined. When an extremely small size (e.g., micro gram)of samples such as micrometeorites recovered on the
Earth surface and tiny particles returned from extraterrestrial asteroids are to be analyzed by INAA, the conventional INAA procedure used for a few tens mg is notsuitable. For such tiny samples, neutron irradiation withhigh neutron flux and long irradiation time (namely, highneutron dose) is required. For the irradiation with highneutron dose, polyethylene bags for holding samples are
not usable because they are prone to radiation damage.
Polyethylene bags are also not suitable for holding tiny
grain samples. It is, therefore, very important to design anappropriate sample holder for irradiating small grain
samples. As we use a relative method for quantification,in this report, the preparation of reference samples andthe evaluation for their suitability are described in detail.

Gamma-ray intensity[108] 40

EXPERIMENTS: Two reference samples with different elemental compositions were used; the Allende meteorite powder (1.66 mg) prepared by the Smithsonian Institution (USMN 3529; split 22 and position 6) and thebasaltic rock reference sample JB-1 prepared by Geological Survey of Japan (1.12 mg). Each sample was sealed
into a synthesized quartz tube (1 mm inner  and 2.7 mm
outer  x 35 mm length), which was then wrapped with
Al foil for the safety. The neutron irradiation was performed for 45 hours at the hydro-irradiation port of Kyoto University Reactor (KUR) in Kyoto University Research Reactor Institute (KURRI) under 1MW operation.

20

AllendeJB-1
JB-1[3]

51

Cr

10

Run-1
Run-2
Run-3
Fig. 1. Gamma-ray intensities of 51Cr in referencemonitors for run-1, run-2 and run-3.
REFERENCES:[1] M. Ebihara et al., Meteorit. Planet. Sci., 50 (2015)
243-254.
[2] M. Ebihara et al., Science, 333 (2011) 1119-1121.
[3] P. Kong and M. Ebihara, Geochem. J., 31 (1997)
339-344.

RESULTS: For quantification in INAA, two reference
samples (the Allende meteorite and the JB-1 basalt) having different elemental contents were used. We haveconducted similar INAA experiments where tiny grain
samples collected by the spacecraft were analyzed by

採択課題番号 26048 京大炉(KUR)における微小隕石及び標準岩石試料の中性子放射化分析 通常採択
（京大・原子炉）関本俊（首都大院理工）海老原充、白井直樹(九大院理)岡崎隆司
122CO5-8Probability distribution of SEL occurred on on-board computer (OBC)
mounted on small-scale satellite
from the ground test is 2.8x105 to 1.4x106 times the
cross-section derived from the on-orbit data.

H. Masui, T. Tomioka, K. Taniwak, M. Cho and K.
Takamiya1
Kyushu Institute of Technology
Research Reactor Institute, Kyoto University

1

INTRODUCTION: Recently universities and venturebusinesses actively develop small-scale satellites. For thesmall-scale satellites, many COTS (Commercial-off-the-shelf) components are used. The COTS components are
not enough durable for space radiation environment. In
particular, a microprocessor embedded to OBC suffers aproblem of Single Event Latch-up (SEL). Horyu-2 was
the small-scale satellite developed by Kyushu Institute ofTechnology (KIT) and actually suffered many on orbit
anomalies due to SEL[1-2]. Therefore, the radiation test
is important for small-scale satellite using the COTS tocharacterize the radiation effect and to find most durable
COTS. However, a radiation test using an accelerator is
not readily available. Since 2012, KIT has been conducting radiation test using 252Cf for small-scale satellite. In
this report, recent radiation tests, using 252Cf, has beenreported. This ground experiment data was analyzed andcompared with the on-orbit data acquired from Horyu-2
in order to investigate the nature of anomaly.

Fig. 1 Test configuration

EXPERIMENTS: Figure 1 shows the schematic oftest configuration. A microprocessor, as device under test
(DUT), was set in a vacuum chamber. The pressure during the test was approximately 30 Pa. The model numberof microprocessor was HD64F36057FZJV and its plastic
cover was removed. The same model microprocessor was
mounted on Horyu-2. The radiation source of 252Cf was
mounted on XYZ stage. By changing a distance from thetest sample to 252Cf, radiation flux was calculated andcontrolled. DAQ and PC1 measured a voltage and currentof the microprocessor. PC2 monitored the operation of
microprocessor with RS232 communication. Just after
the SEL occurred each time, a reset command was sent to
the microprocessor. If the microprocessor was not recovered due to SEL, power was turned off.

Fig. 2 Probability of SEL occurrence for various fluxes
Table 1 Comparison between 252Cf test andon-orbit anomaly
252
Cf test
Orbit
Flux, 1/cm2/s
37
13
6.4
64
Simple average
3.4x106
19.3 42.2 86.3
time, s
Cross section of
1.3x10-6
1.3 1.8
1.8
SEL, x 10-3 cm2

RESULTS: 100 times SELs were observed and the time
between SELs was measured for each flux condition.
Figure 2 shows the probability distribution of a SEL occurrence with respect to time[3] at three different distances. As shown in Fig. 2, the time between SLEs is
increased with increasing of the flux and the probability
follows the Poisson distribution. Table 1 shows a SEL
occurrence time and the cross-section for ground experimental. On-orbit data from 2012 to 2015 is also shown. A
simple average SEL occurrence time was 1.2x107 sec (=139 days) from the orbit data. The cross-section derived

REFERENCES:[1] M. Cho et al., The Japan Society for Aeronautical andSpace Sciences, 12(0), 17-24, 2013.
[2] Y. Seri et al., SSC13-X-8, Small Satellite Conference,
August, 2013.
[3] T. Tomioka et al., Acta Astronautica, submitted for
publication.

採択課題番号 26053	
 カリフォルニウム線源を使用した衛星搭載用
通常採択
オンボードコンピュータに発生するシングルイベントの模擬試験および試
験方法の確立	 （九工大・先端）増井博一、冨岡孝裕、谷脇康洋、趙孟佑（京大・原子炉）高宮幸一	
 123CO5-9Instrumental Photon Activation Analysis of Geological and Cosmochemical Samples

N. Shirai, S. Sekimoto1, M. Ebihara

celerator at the Research Reactor Institute, Kyoto University. Electrons were accelerated by the linear accelerator to about 30 and 20 MeV. After irradiation (about 30
hours), samples were taken into new Al foil and measured at the Laboratory of Radioisotopes, Tokyo Metropolitan University. For comparative method, JB-1 wasused as reference standard.
RESULTS: Table 1 shows the interfering reactions andtheir contributions to nuclides produced by corresponding
reactions for activation with 20 MeV and 30 MeV electrons. As shown in Table 1, significant contributions
from interfering reactions were found in activation with
30 MeV electrons. Thus, determinations of Cr, Co and
Mn abundances need the correction of corresponding
interferences. As expected, contributions from interfering
reactions with 20 MeV electrons were lower than those inactivation with 30 MeV electrons.

Department of Chemistry, Tokyo Metropolitan University
Research Reactor Institute, Kyoto University

1

Normalized to reference values

INTRODUCTION: Bulk chemical compositions forterrestrial and cosmochemical materials are significantly
important to elucidate the formation, evolution processes
and magmatism of planetary bodies. Compared to geological samples, cosmochemical samples pose several
severe requirements to their analytical methods forchemical compositions. High sensitivity and accuracy foras many as elements as possible are required for analytical methods applied to such samples because of the limitation of sample amounts usable for analysis.
Non-destructive analysis for many elements is equallyfavorable. Nuclear analytical methods represented byprompt gamma-ray analysis (PGA), instrumental neutron
activation analysis (INAA) and instrumental photon activation analysis (IPAA) meet almost all these requirements. Among these nuclear analytical methods, INAA
has been commonly used as an analytical tool in comomochemistry for a long time, while PGA and IPAA havenot been very often applied to cosmochemical samples.
	  In IPAA, (γ,n) reaction is used for the determination ofelemental abundances which is an opposite reaction usedin INAA. Thus, IPAA could determine elemental abundances which cannot or hardly be determined by INAA.
Usually samples are irradiated by using 30MeV electronsin IPAA. However, corrections of interferences caused bysecondary nuclear reactions such (γ,p) and (γ,pn) arenecessary. Although the sensitivity obtained by activation
with 20MeV electrons are suppresses compared with theactivation with 30MeV electrons, activation with 20MeV
electron reduces the degree of such interference reactions.
In this study, we performed IPAA by using a linear electron accelerator at Kyoto University Research Reactor
Institute (KURRI) and compared the results obtained by
the activation with 20 MeV with those with 30 MeV.
EXPERIMENTS: Three GSJ standards materials namely JA-2 (andesite), JB-3 (basalt) and JR-1 (rhyolite) and
one cosmochemical sample (Allende meteorite) wereanalyzed by IPAA. Chemical reagent sample, Fe2O3
powder and Cr, Mn and Ni metals were also irradiated tocorrect the interference reactions. Samples and chemical
reagents were taken into a sample container (9 mmφ)
made of highly Al foil. Five to ten samples were stacked,
among which thin foil disk (9 mmφ) of Au as a monitor
of the intensity of photon are placed. Samples in a block
were put in a quartz tube. We used a linear electron ac-

1.2
1.1

JR-1

JA-2

JB-3

Allende

1
0.9
0.8
0.7
0.6
0.5
0.4

Figure 1. Our Mn values obtained by using 20 and 30 MeV electrons
are compared with the corresponding reference values. Solid andopen symbols represent that data are determined by using 30 and
20 MeV electrons, respectively.

	  A total of 17 elements (Ca, Sc, Ti, Cr, Mn, Fe, Co, Ni,
Zn, As, Rb, Y, Zr, Nb, Cs, Ba and Ce) were determinedin geological reference materials and the Allende meteorite. Our Cr and Mn values obtained from activation with
30 MeV electrons were different from literature values.
Our Mn values obtained by using 20 and 30 MeV electrons are compared with reference values in Figure 1. For
four samples, Mn values obtained by using 20 MeV electrons are consistent with reference values, while those byusing 30 MeV electron are lower than literature values.
Differences of Mn values in JB-3 and Allende between
30 and 20 MeV electrons are more remarkable than thosein JR-1 and JA-2. Fe/Mn ratios of JR-1, JA-2, JB-3 andAllende are 8.1, 52, 60 and 162, respectively. In consideration of Fe/Mn ratios, overcorrections of the interfering
reactions were responsible for these differences. For other elements, there were no differences between the two
sets of our values obtained from the activations with 20
and 30 MeV electrons, which were consistent with literature values.

Table 1. Interfering reaction and correction rate for interference.
Reaction used forInterfering
Correction rate
determination
reaction
30 MeV
20 MeV
52Cr(γ,n)51Cr
56Fe(γ,αn)51Cr
0.036 mgCr/gFe
59Co(γ,n)58Co
60Ni(γ,pn)58Co
3.7 mgCo/gNi
0.88
mgCo/gNi
55Mn(γ,n)54Mn
56Fe(γ,pn)54Mn
6.2 mgMn/gFe
0.1 mgMn/gFe	
 採択課題番号
26067	
 放射化分析による宇宙・地球化学的試料の元素組成の定量	 （	 (首都大学東京理工）白井直樹、海老原充（京大・原子炉）関本俊	
 

124

通常採択

CO5-10Decomposition of Perfluorooctane Sulfonate by Gamma Ray Irradiation

A. Hashiguchi, M. Yoneda, Y. Fujikawa1

pyl alcohol (IPA) and alkaline potassium persulfate
solutions. Both solutions were purged with nitrogengas before the irradiation. The use of persulfate wastested because the substance is a known radical initiator that produces sulfate radical throughS2O82-→2SO4-・reaction. As a control, ethanol (a radical
scavenger) spiked with PFOS was also irradiated. The
IPA and persulfate solution was subjected to solid phaseextraction by Oasis HLB (strongly hydrophilic and lypophilic, Waters) resin prior to determination of PFOS.
Direct photolysis of solid PFOS by gamma-ray was investigated by irradiation of a 20μL drop of PFOS (concentration: 1g/L-methanol), dried on a microscope slide,and covered with a cover glass.
Irradiation dose was estimated by ceric sulfate dosimeter
utilizing the reduction of Ce4+ to Ce3+ by the radiation, or
the calculation considering the distance and angle fromthe 60Co radiation source. Concentrations of PFOS in
sub-samples collected before and after the irradiation
were determined by UPLC-MS/MS (Waters).
RESULTS: Fig.1 shows the decrease in the numbers of
PFOS molecules after gamma-ray irradiation of the dried
residue of PFOS solution. The decrease of PFOS molecules was roughly proportional to the adsorbed dose. Interestingly, the rate of decrease was strongly dependent
on the dose rate,
3E+16
and was faster at
2.5E+16
0.7‐0.9 kGy/h y = ‐2E+14x + 2E+16
the higher dose rate.
R² = 0.8352
2E+16
Since the genera1.5E+16
y = ‐8E+15x + 2E+16
tion of radicals in
R² = 0.9346
1E+16
the dried residue is
5E+15
negligible, the de1.5 kGy/h0composition
of
0
10
20
30
kGy
PFOS is attributed
Fig. 1 Decomposition of dried PFOS residue with time (kGy)to photoexcitationof PFOS followed by its decomposition. It has been
known that upon irradiation with UV, perfluorooctanoic
acid (PFOA), one of the PFCs known for its refractoriness, was decomposed, and the mechanism of decomposition was ascribed to direct photolysis rather than toradical reaction [1]. On the other hand, the decompositionof PFOS by UV has not been found so far. The present
result indicates that high energy photon (1.16 and 1.33
MeV γ ray from 60Co in this case) was probably needed
to induce the direct photolysis of PFOS.
The decomposition of PFOS in ethanol was 30% (initially 2.3× 1015 molecules) after 42 kGy (dose rate 2.7
kGy/h) of irradiation. After 38 kGy (dose rate 0.67
kGy/h) of irradiation, only 6 % of PFOS was decomposed in alkaline persulfate, while in IPA, 85% of PFOS
was decomposed, due probably to the radical reactions.
REFERENCES:[1] R. R. Giri et al., Water Sci. & Technol., 63 (2011)276-282.

Graduate School of Engineering, Kyoto University
1
Research Reactor Institute, Kyoto University

採択課題番号 26074（京大・原子炉）藤川

PFOS molecules

INTRODUCTION:
Perfluoro compounds (PFCs),
characterized by high chemical and thermal stability,
have been widely used in the world as water and oil repellent, car wax and fire extinguisher, etc. Among various
PFCs, perfluorooctane sulfonate (PFOS), a linear perfluoroalkyl sulfonate with eight carbon-chain length, hasbeen noted for its high bioaccumulation potential to wildlife and persistence in the environment. Among the various environmental problems associated with this recalcitrant substance, we were most interested in development of a practical technology that could be used
to polish-up the wastewater containing PFOS.
Existing practical treatment methods for removal of
PFOS from sewage effluent or wastewater are membrane filtration (especially reverse osmosis), or adsorption using activated carbon. Use of these methods
has a figure of merit as they are already installed inmany treatment plants, and the operation and management protocols for various micro-pollutants are
fairly well established. On the other hand, PFOS is notdecomposed by these methods, only concentrated in
the reject or adsorbents. A technique that can decompose PFOS in the concentrate is needed.
Photo-assisted methods have been known to be effective for decomposition of pollutants in air and water.
The treatment is done either via direct photoexcitationof the pollutant or mediated processes involving highly
reactive radicals generated by photolysis. UV light iscommonly used for the technology, but for particularly
recalcitrant pollutants such as PCBs and chloro-fluoro
aliphatic carbons, γ ray irradiation has been proved tobe most effective. The OH radical, solvated electron,and radical or cation of isopropyl alcohol (added as asource of organic radicals), produced in the mediumby γ ray, degraded the pollutants through reductive
dehalogenation processes.
In our study, we irradiated the PFOS in various media
withγray to investigate the possibility of decomposition of PFOS via direct photolysis or radical reactions.
EXPERIMENTS: A 414 TBq (as of February, 2008)60
Co in γ ray irradiation facility in KURRI was used asa γ ray source. All the reagents used were Japan Industrial Standard reagent grade unless stated otherwise.
Known amount of PFOS powder purchased from
Wako Chemical Industry was dissolved in methanol(HPLC grade), and was used to spike alkaline isopro-

難分解性有機フッ素化合物のγ線照射・分解実験
陽子（京大院・工）橋口 亜由未、米田 稔

125

通常採択