FY2018 (2018.4‐2019.3) NSEC
Annual Report

Nuclear Science and Engineering Center
Nuclear Science Research Institute, Sector of Nuclear Science Research
Japan Atomic Energy Agency

September 2019

This report is issued by Japan Atomic Energy Agency.
Inquiries about availability and/or copyright of this report should be addressedto the Research Coordination and Promotion Office of the Nuclear Science andEngineering Center, Japan Atomic Energy Agency.
2‐4 Shirakata, Tokai‐mura, Naka‐gun, Ibaraki‐ken 319‐1195 Japan.
E‐mail: nsed‐web@jaea.go.jp© Japan Atomic Energy Agency, 2019

Table of Contents

Preface........................................................................................... 1

R&D Highlights............................................................................... 2Group Activities.............................................................................. 9

Organization of NSEC··············································································································· 10

Nuclear Data and Reactor Engineering Division ······························································· 11
Nuclear Data Center
Research Group for Reactor Physics and Standard Nuclear Code System
Research Group for Nuclear Sensing
Fuels and Materials Engineering Division ·········································································· 14
Research Group for Corrosion Resistant Materials
Research Group for Radiation Materials Engineering
Research Group for High Temperature Science on Fuel Materials
Nuclear Chemistry Division ···································································································· 17
Research Group for Radiochemistry
Research Group for Analytical Chemistry
Environment and Radiation Sciences Division ·································································· 19
Research Group for Environmental Science
Research Group for Radiation Transport Analysis
LWR Key Technology Development Division ····································································· 21
Development Group for Thermal-Hydraulics Technology
Development Group for LWR Advanced Technology
Partitioning and Transmutation Technology Division ····················································· 23
Research Group for Partitioning
Research Group for Nuclear Transmutation System Technology
Research Group for MA Transmutation Fuel Cycle

Publication List............................................................................. 26

FY2018 NSEC Annual Report

PrefaceAkira ENDO
Director General, Nuclear Science and Engineering Center

It is our great pleasure to present to you the first annual report of the Nuclear Science andEngineering Center (NSEC) of the Japan Atomic Energy Agency (JAEA). This report provides ourresearch highlights and an overview of the research groups’ activities for Fiscal Year 2018.
The NSEC aims to conduct research and development to advance the science and technologythat supports the use of nuclear energy and radiation. As such, we conduct varied research from
elucidating various phenomena using our innovative techniques to developing computer
simulation codes and databases. These cover nuclear data and reactor engineering, nuclear fueland material engineering, nuclear chemistry, and environment and radiation sciences.
Through such knowledge and technologies, the NSEC contributes to solving various issues. Since
the accident at the TEPCO Fukushima Daiichi Nuclear Power Plant, we have focused on researchand development that contributes to the (1) accident response (promoting facility
decommissioning and environmental restoration), (2) improvement of light water reactors’safety performance, and (3) steady implementation of the treatment and disposal of radioactive
waste. Additionally, we disseminate our innovative technologies to resolve challenges in various
fields, such as industry, environment and medicine.
We strive to become a leading center for research collaboration and use our fundamental
research and development capabilities to contribute to advances in science and technology. We
hope this annual report will increase your understanding of the NSEC.

September 2019
1

FY2018 NSEC R&D Highlight

FY2018 NSEC R&D Highlights
The following 6 highlights are selected among various outcomes of the R&D
activities accomplished by the NSEC’s 6 divisions in FY2018.
 Nuclear Data and Reactor Engineering Division:“Theoretical prediction of transmutation by deuteron”
 Fuels and Materials Engineering Division:“Computer design of high toughness alloys – A study for Mg –” Nuclear Chemistry Division:“Chemical bonding between metal ion and separation reagent reveals
Am/Cm selectivity”
 Environment and Radiation Sciences Division:“Prediction of scintillation light yield by micro-dosimetry”
 LWR Key Technology Development Division:“A numerical simulation code JUPITER for melting behavior in nuclear
reactors based on computational fluid dynamics”
 Partitioning and Transmutation Technology Division:“Development of the “SELECT Process” to separate radioactive waste”

2

FY2018 NSEC R&D Highlight

Theoretical prediction of transmutation by deuteron
Shinsuke Nakayama,1 Naoya Furutachi,1 Osamu Iwamoto,1 and Yukinobu Watanabe2
1 Nuclear Data Center, 2 Kyushu University
Among radionuclides produced in a nuclear reactor,
those with long half-lives require long-term
management and hence it is strongly desired toconvert them into stable or short-lived ones.
Spallation reaction is one of the candidates especiallyfor transmutation of long-lived fission products(LLFPs). In recent years, it has been suggested that theuse of deuteron as an incident particle improves theefficiency of transmutation, compared to othercharged particles such as proton.
For the feasibility study of transmutation system witha deuteron primary beam, accurate cross section dataof deuteron-induced reactions over a wide range oftarget mass numbers and incident deuteron energies
are indispensable. However, the amount of currently
available experimental data of deuteron-induced
reactions do not necessarily meet the requirement. In
such a case, reliable theoretical model calculations
play a key role in providing the necessary cross section
data by interpolating or extrapolating experimental
ones.
Under the above situations, we have been developinga code system dedicated for deuteron-induced
reactions, called DEURACS [1]. In the present study [2],we improved DEURACS and applied it to thecalculation of deuteron-induced spallation reactions
on typical LLFPs. In deuteron-induced reactions, three
types of composite nuclei can be formed by theabsorption of either neutron or proton in the incident
deuteron, or the absorption of the incident deuteronitself. In DEURACS, a calculation considering this effectis performed. On the other hand, in the conventional
codes for nucleon-induced reactions, such as CCONE,
it is assumed that composite nuclei are formed only
from the deuteron absorption.
Figure 1 shows the calculated and experimental
isotopic production cross sections for the 93Zr+dreaction at the incident deuteron energy of 210 MeV.
For comparison, we also present the calculation
results with the CCONE code, in which the deuteronbreakup processes are not taken into account. As
shown in the figure, obvious differences are seen
between the two calculations, and DEURACS
reproduces the experimental data well in the wide
range of mass number. Moreover, we have confirmedthat the calculated values of DEURACS are in good
agreement with the experimental ones also for the107
Pd+d reactions at the incident deuteron energies of
236 and 392 MeV.
From these results, it can be concluded that theframework of the improved DEURACS is applicable todeuteron-induced spallation reactions on LLFPs.
These results also demonstrate that consideration of
the breakup processes is essential to predict
deuteron-induced spallation reactions.
Research and development on a transmutation
system using a deuteron primary beam will makegreat progress by the present work. In addition, theresult of the present work is expected to make a large
contribution to various fields related to deuteroninduced reactions, such as production of medical
radioisotopes, radioactivity evaluation in deuteronaccelerator facilities, and so on.
This work was funded by ImPACT Program of Council
for Science, Technology and Innovation (Cabinet
Office, Government of Japan).
Reference
1) S. Nakayama et al., Phys. Rev. C 94, 014618 (2016).
2) S. Nakayama et al., Phys. Rev. C 98, 044606 (2018).

Fig.1 Calculated and experimental isotopic
production cross sections for the 93Zr+dreaction at 210 MeV.
The closed circles are the experimental data.
The solid and the dashed curves represent thecalculation results of DEURACS and CCONE,
respectively.

3

FY2018 NSEC R&D Highlight

Computer design of high toughness alloys –A study for Mg–
Tomohito Tsuru
Research Group for Radiation Materials Engineering
Mg alloys are promising candidates for next
generation lightweight structural materials, especiallyfor transportation equipment in terms of energy andenvironmental conservation. However, widespread
application of wrought Mg alloys is limited because of
their low formability at room temperature. The low
formability of Mg alloys is caused by their low ductility
and fracture toughness. The former is because of theirstrong plastic anisotropy originating from theirhexagonal close-packed (HCP) structure and the latter
is attributed to the intrinsic feature of their electronic
structure.
An important property to improve the formability is
the fracture toughness because pure Mg isintrinsically brittle, where local strain concentration
occurs at twin boundaries (TBs) and cracks mainly
propagate along these boundaries. We havesystematically investigated the fracture toughness of
Mg-M binary alloys from the viewpoint of the effectof solute elements. In the present study, we introduce
an electronic-structure-based approach combinedwith fracture mechanics to understanding the effectof solute elements on interfacial fracture of Mg alloys.
Rather than solely focusing on the segregation energy
at the surface and interface, we focus on thecomprehensive mechanism caused by the electronic
structure, which dominates cohesion or decohesionof the interfacial fracture.
Figure 1 shows atomic models of typical TBs observedin experiments. We constructed several types of TB
configurations to investigate the effect of various
solute elements on the ideal work of interfacial
separation. Three different TBs were constructed toinvestigate the difference in the type of boundary,including energetically stable and unstableboundaries. We calculated the surface energy of freesurface was evaluated as well as the interfacial energy
and applied the energy-based Griffith criterion forcrack propagation [1]. The theory and computational
procedure are described in our paper.
The difference in the ideal work of interfacial
separation between the Mg-M alloys and pure Mg interms of the site occupancy at the TB site for the(1012) TBs is summarized in Fig. 2 (a), where positive
value corresponds to solute with toughness andnegative to solutes with embrittlement. The values for
Li, Ca, Sn, and Pb are very small or negative, whichindicates that these elements cause segregationinduced embrittlement at the interface. On the other
hand, the other solutes show positive values and Zr
has the highest among them. Finally, we compare thecalculated values with experiments in Fig. 2 (b), where

our prediction shows good agreement with theexperimental values and the toughness is indeed
improved by Zr solute. We conclude that theelectronic interactions of both the bulk and thesurface and their difference characterize the fracture
toughness of binary alloys [2]. We hopecomputational simulations plays more important rolein the effective approach for new alloy design.
This work is supported by “JSPS KAKENHI (Grant Nos.
16K06714, 16K06783)” and “the U.S. Office of Naval
Research under Grant N00014-16-1-2304”.
Reference
1) A.A. Griffith, Philos. Trans. R. Soc. A, 221, 582–593, (1921).
2) T. Tsuru, et al., Acta Mater., 151, 78–86, (2018).

Reprinted from JAEA R&D Review 2018-19, 47,(2019)

Fig.1 Atomic models of the interfaces. Atomic
configurations of the various interfaces.

Fig. 2 (a) Energy of interfacial separation in terms of
the site occupation. (b) Relationships between
experiments and calculations.

4

FY2018 NSEC R&D Highlight

Chemical bonding between metal ion and separation reagent reveals Am/Cm
selectivity
Masashi Kaneko
Research Group for Radiochemistry

In order to reduce the toxicity of high-level radioactive
liquid waste (HLLW), the partitioning of minor
actinides (MAs), which are extremely long-lived, andthe transmutation to short-lived nuclides, partitioning
and transmutation, has been developed. In thepartitioning process, the separation of americium(Am) from curium (Cm) has been required due to theheat generating property of Cm. However, thesimilarity of chemical properties between Am and Cm
has made it difficult to separate them. JAEA has
developed the separation process of Am from HLLW—SELECT process—to succeed in the selective
separation of Am from Cm by using
alkyldiamideamine (ADAAM) reagent1. This study
revealed why the ADAAM reagent shows the high Am
selectivity over Cm by using density functional theory
calculation2.
Am and Cm exist as a trivalent ion, Am3+ and Cm3+, andform the complex with reagents. First, I modeled thecomplex, consisting of the metal ion (M3+), nitrate ion(NO3–), and ADAAM reagent, as [M(ADAAM)(NO3)3]
by referring to the result of the previous separation
experiment1 (Fig. 1). Second, I calculated the Gibbs
energy difference of the formation of each complex.
The comparison of the stability between the Am and
Cm complexes indicated that the Am complex is morestable than the Cm complex. The calculated value ofthe separation factor of Am from Cm was 6.2 andreproduced the experimental value, 5.5.
I focused on the coordination bonds between themetal ion and ADAAM reagent to understand the Am
selectivity over Cm of the ADAAM reagent. The
ADAAM acts as tridentate ligand, one amine nitrogen
atom and two carbonyl oxygen atoms. The
comparison of the bond length between the metal ion
and ADAAM reagent indicated that the metal-N bondlength was 2.91 and 2.94 Å for Am and Cm complexes,
respectively. Furthermore, I analyzed the covalentinteraction of the coordination bonds by calculating
the overlap of electron orbitals between the metal ion
and nitrogen atom (in arb. unit). The orbital overlapof Am–N bond was larger than that of Cm–N bond (Fig.
2). This result indicated that the Am–N bond isstronger than the Cm–N bond. These results impliedthat the difference in the strength of the covalentbond between a metal ion and ADAAM reagent is a
key to understand the Am/Cm selectivity. This study is
expected to contribute to fundamental chemical

aspects; such as understanding the bonding
properties of f-block coordination compounds, as well
as applied chemical aspects; such as the developmentof the MA partitioning process by theoreticallydesigning extraction reagents with high and efficient
MA selectivity.
This work was supported by JSPS KAKENHI Grant
Number JP17K14915.
Reference
1)
2)

H. Suzuki, et al., Anal. Sci., 33, 239-242 (2017).
M. Kaneko, et al., Inorg. Chem., 57, 14513-14523(2018).

ADAAM

R2N
O

N
R'

NR2
O

+ M3+
+ NO3–ADAAM
M3+

Fig.1 AAA (10pt, タイトルは太字)
NO3–Fig. 1 Structure of model complex consisting of
metal ion, ADAAM reagent, and NO3− ions.

Fig. 2 Chemical bonding analysis of metal ion and
ADAAM reagent.

5

FY2018 NSEC R&D Highlight

Prediction of scintillation light yield by micro-dosimetry
Tatsuhiko Ogawa1, Tetsuya Yamaki2, Tatsuhiko Sato1
1 Research Group for Radiation Transport Analysis, 2 Takasaki Advanced Radiation Research Institute,
National Institutes for Quantum and Radiological Science and Technology
Scintillators detect radiation by converting thedeposited energy to photons (= scintillation light),
which are subsequently converted to electric signals.
One of the advantages of scintillators is linearity ofthe scintillation light yield to the deposited energy;
therefore scintillators are applied to measure theparticle energies or to identify the particle species.
However, it was known that the linearity is broken
in case of high-LET (linear energy transfer) particle
incidence because of the quenching effect. Birks’ law[1] was commonly used to estimate the light output
of scintillators with consideration for quenchingeffect. It assumes that light yield per unit particle
flight path is described as a function of LET; therefore,
it is not adequate for neutral particles, to which LET
cannot be defined.
Since the quenching effect is a result of theinteraction between excited fluorescent molecules,
the following calculation procedures were combinedin this study to estimate quenching effect universally[2]: 1, transport of radiation down to a few eV. 2,
energy transfer between fluorescent molecules. 3,
dissipation of the energy, which was excessively
deposited to one molecule. In procedure 1, thedelta-rays produced by the incoming radiation or its
secondary particle were transported until they reacheV range by using RITRACKS code [3]. Procedure 2
was calculated on the basis of dipole interaction(Förster effect) between the excited fluorescentmolecules. After procedure 2, all the excitedmolecules were assumed to emit one photon. Even if
some molecules received excitation energy morethan once, they deexcited non-radiatively to the 1st
excitation state and emitted one photon likewise
other molecules.
Figure 1 shows the light yield of NE-102A, one of
the most common plastic scintillators, irradiated with
protons or electrons of various energies. All
calculated data were normalized for 1 MeV electrons(i.e. the light intensity owing to 1 MeV electrons is 1
MeVee). Both the calculated and the measured lightyields due to electrons increase linearly with theincident energy because energy deposition byelectrons is so sparse that quenching is weak. By
contrast, the light yield due to protons is suppressedstrongly by quenching.
The light yield was also calculated for heavy ionsand compared with earlier measurement data [4] inFigure 2. Our model reproduced the light yield by
various particles from protons to 81Br in the low

energy range, where quenching effect is strong.
The method developed in this study is useful topredict the response of scintillators as well as
designing detector systems, such as telescope
detector to distinguish particle species.
We wish to acknowledge Dr. Ianik Plante of NASA
Johnson Space Center for the upgrade of RITRACKS
for transport of ions heavier than Ni.
Reference
1) J.B. Birks, Proc. Phys. Soc. A, 64(10) 874, (1951).
2) T. Ogawa, T. Yamaki, T. Sato, PLoS ONE 13(8), e0202011(2018)
3) I. Plante, et al., 18. Monte-Carlo Simulation of Ionizing
Radiation Tracks (in “Applications of Monte Carlo
Methods in Biology, Medicine and Other Fields ofScience (Edited by Charles J. Mode)”), IntechOpen(2011).
4) F.D. Becchetti, et.al., Nuclear Instruments and Methods,
138, 93-104, (1976).

Fig.1
Comparison of scintillation light yield owing to
MeV-class protons and electrons

Fig.2 Comparison of scintillation light yield owing toheavy ions6

FY2018 NSEC R&D Highlight

A numerical simulation code JUPITER for melting behavior in nuclear reactors
based on computational fluid dynamics
Susumu Yamashita1, Kenichi Tada2 and Hiroyuki Yoshida1
Development Group for Thermal-Hydraulics Technology, 2Research Group for Reactor Physics and1Standard Nuclear Code System

material, Zry, is located at the upper part. This
distribution is given by mechanistic estimation formelt relocation and solidification based upon thephysical governing equations.
In addition, we try to evaluate the re-criticality of fueldebris in the pedestal using the continuous-energyneutron-transport Monte Carlo code MVP with thisfuel-debris distribution by JUPITER. In an ordinary
criticalicality analysis, it is assumed that the fueldebris is uniformly mixed, and effects of debris
distribution are neglected. Here, with the distribution
given by JUPITER, re-criticality can be calculated
under more realistic conditions. As a result, we
confirmed effects of nonuniform distribution of thedebris on the re-criticality analysis.
Recently, JUPITER has been released at PRODAS [2].
We are continuously improving JUPITER to enhance
the light water reactor safety. In addition,
decommissioning of Fukushima-Daiichi NPS by
evaluating the characteristics and re-criticality of fueldebris through updating the numerical models andcalculating the melting behaviors under severe
accident conditions.

Melting and relocation processes of reactor core
structures (control rod, fuel assembly, etc.) are quite
important to the accident scenario and debris
distribution during severe accidents (SAs). However,melting behaviors still have a lot of uncertainties andare not yet fully understood. Although conventional
SA-analysis codes have been attempting tounderstand melting behavior, detailed melting
behavior of such structures was not revealed yet
because of uncertainties of numerical models, e.g.,assumptions about the phenomena and simplify theshapes of reactor-core structures, in SA analysis-codes.
And there is no detailed melting behavior simulation
code until now.
Therefore, we have developed a numerical-simulation
code for melting and relocation behavior called
JUPITER, based upon a mechanistic methodology.
JUPITER can simulate melting and relocation without
assumptions or simplification using basic equations
governing the thermal-hydraulic behavior of the fluids
in Eulerian grid system. Besides the fluid dynamics
models, chemical reaction such as an eutectic
reaction and oxidation model can also be taken into
account, which is based on material science.
Therefore, the melting behavior induced by oxidationand eutectic reaction is estimated mechanistically inthe fully Eulerian grid system.
Because melting phenomena in a nuclear reactor arecomplicated, huge computational resources will be
required. In order to realize the massively parallel
computing in the state-of-the-art supercomputer,high-efficient parallel computing techniques werealso implemented to JUPITER. Then, parallel
computation using more than two hundred thousand
cores was performed successfully.
By using JUPITER, we simulated melt-relocation fromthe bottom of reactor pressure vessel to the lower
part of the primary containment vessel (pedestal) [1].
In this simulation, we assumed the highest density
material, molten UO2, should be poured first,
followed by the lower density materials stainless steel,Zry, and B4C. Fig.1 shows a cross-sectional view of thedebris in the pedestal along its center to illustrate theaccumulation state inside the sump pits. The meltnear the wall of the pedestal is solidified by heattransfer to the wall. The highest density material, UO2,
is located at the bottom and the lowest density

Reference
1) S. Yamashita et.al., Trans. of AESJ, 17, 99-105, (2018) (inJapanese).
2) PRODAS (PROgram and Database retrieval System),
http://www.rist.or.jp/nucis/

Fig.1 Interior distribution of accumulated debris(numerical result)

7

FY2018 NSEC R&D Highlight

Development of the "SELECT Process" to separate radioactive waste
Tatsuro Matsumura
Research Group for Partitioning
process is shown as Fig. 1. SELECT process consists ofthe following four steps: (i) recovery of U and Pu from
dissolution solution of spent nuclear fuels, (ii)
recovery of Am, Cm, and rare earth elements (REs)from HLW, (iii) separation of REs from Am and Cm, and(iv) separation of Am and Cm.
We conducted a continuous counter-current
experiment using mixer-settler extractors installed ina hot cell at NUCEF (NUclear fuel Cycle safety
Engineering research Facility) at the Nuclear Scienceand Research Institute to evaluate the applicability of
TDdDGA as an extractant for the 2nd step (Fig. 2). The
experiment was performed successfully over a
cumulative operation time of 10 h. TDdDGA
effectively extracted Am and Cm. More than 98% of
Am and Cm were recovered and not detected in theraffinate. The recovery of Y, La, Nd, and Eu were 94.0%,
99.9%, 99.9%, and 86.9%, respectively. Furthermore,
the recovered MAs and REs had no remarkablecontamination with fission products such as Sr, Cs, Zr,
Mo, Ru, Rh, and Pd.
The present results demonstrated that TDdDGA canbe used as the extractant in the 2nd step, andpromoted the development of SELECT process.

Partitioning and transmutation (P&T) has been
proposed as one of measures to reduce theradioactive toxicity and the volume of radioactive
waste generated from the reprocessing of spent
nuclear fuels by hydrometallurgical method. To thisend, highly toxic radionuclides should be separated
from high-level radioactive liquid waste, and studies
for developing practical partitioning processes havebeen carried out. The former processes proposed todate demonstrated excellent performance toseparate fission products (FPs), rare earths (REs) andminor actinides (MAs), however, some processes
employed the reagents consisted of phosphorus or
sulfur which cannot be decomposed into gases byincineration.
Thus, we have been developing the extractantsconsisting of carbon, hydrogen, oxygen, and nitrogenatoms (so-called CHON principle) in that such
extractants can be decomposed into gases byincineration and this leads to decrease in the volumeof the secondary waste. Recently, we have proposed
a hydrometallurgical method called SELECT (Solvent
Extraction from Liquid-waste using Extractants of
CHON-type for Transmutation) aiming at recycle useof nuclear materials and separating actinides fortransmutation. A conceptual flow sheet of SELECT

Reference
1) Y. Ban, et al., Solvent Extraction and Ion Exchange, 37(1),27-37, (2019).

Dissolution solution of spent nuclear fuelStep 1 U and Pu recovery
DEHDMPA

DEHBA

U, Pu

Step 2 Recovery of Am, Cm, and rare earths
TDdDGA

FPs otherthan REs

Step 3 Separation of REs from Am and Cm
HONTA
Step 4 Separation of Am and Cm
ADAAM(EH)

REs
Am
Fig.2 Mixer-settler extractors used in thecontinuous counter-current experiment to recover
Am, Cm, and rare earths by TDdDGA.

Cm

Fig.1 A conceptual flow sheet of SELECT process andproposed extractants in each step8

FY2018 NSEC Group Activity

FY2018 NSEC Group Activities
The NSEC of JAEA consists of 15 Groups.

9Organization of NSEC10NSEC URL: https://nsec.jaea.go.jp/en_index.html（as of September 2019）

FY2018 NSEC Annual Report

FY2018 NSEC Group Activity

Nuclear Data Center
Revision of the data of structure material is one ofmain targets, because they are important forneutron transportation in material and also for
their activations. Neutron cross sections were
evaluated for Zr and Cu isotopes using the state-ofthe-art nuclear reaction model code CCONE
developed at JAEA. The available experimental dataof various nuclear reactions, elastic scattering
angular distributions, secondary neutron emission
spectra were consistently analyzed by CCONE anddeduced the reliable evaluated data3,4).

The mission of Nuclear Data Center is to provide
reliable nuclear data which are required in various
applications such as nuclear reactors, accelerators,
medical use of radiations, and so on. To achieve it,
we engage in research works on nuclear datameasurement, nuclear theories, and nuclear data
evaluation related to nuclear reaction and structure
collaborating with nuclear data researchers andorganizations in Japan as well as in the world. The
evaluated nuclear data have been compiled into
databases called JENDL and are available from our
website http://wwwndc.jaea.go.jp.

Reference

1) K. Terada et al., J. Nucl. Sci. Technol, 55, 1198-1211, (2018).
2) S. Nakamura et al., J. Nucl. Sci. Technol, 56, 123-129,(2018).
3) A. Ichihara, J. Nucl. Sci. Technol, 55, 1087-1098, (2018).
4) S. Nakayama, J. Nucl. Sci. Technol, 55, 614-622, (2018).

Measurement of MA cross sections

Cross sections of minor actinide (MA) are importantin estimating production of MA in nuclear reactors
and also needed in research on reduction of MA bynuclear transmutation. Total and capture crosssections of neutron reaction on 241Am were
measured in high accuracy with ANNRI installed at
MLF in J-PARC1). In this work, uncertainty originatedfrom amounts of the Am samples was significantly
reduced by the utilization of a calorimeter which
could measure decay heat of samples precisely. The
total cross section was determined from 4 meV to
2 eV and capture cross section from 10 meV to 100
eV by time-of-flight method. The thermal capture
cross sections were obtained with uncertainties of
4.1% which is nearly a half of current uncertainty ofevaluated data of JENDL. Obtained capture crosssection is shown in Fig.1.

10,000

Cross section (b)

1,000
100
10
1

0.01

0.10

1.00
10.00
Neutron Energy (eV)100.00

Fig.1 Am-241 neutron capture cross section

Measurement of γ-ray emission
probability of Am

The γ-ray emission probability Iγ is a basic propertyof nucleus and important to determine the amountof radiative material. The Iγ of 244gAm were
measured by the activation method using neutron
capture reaction on 243Am at Kyoto University
Research Reactor Institute2). Using the known
decay scheme, the absolute value of Iγ for the
principal transition was precisely determined withthe uncertainties of a few % which was remarkably
reduced from almost 30% in the latest version of
Table of Isotopes. Obtained emission probabilities
are shown in Table 1.

Energy Eγ

Emission(keV)

probabilities (%)

153.86317.1 ± 1.2

538.400<0.42

743.971

66.5 ± 1.1

897.84828.0 ± 1.0

Table 1 γ-ray emission probability of 244gAm

Contact (Group Leader):Osamu IWAMOTO
iwamoto.osamu@jaea.go.jp

Evaluation of Cross Sections

Next version of JENDL is under development.

11

FY2018 NSEC Group Activity

Research Group for Reactor Physics and Standard Nuclear Code System
continuous energy Monte Carlo codes such as
PHITS and MCNP. The FRENDY version 1 wasreleased in March 2019 as an open source softwarefrom our group’s home page.5)

The role of nuclear codes is increasing because of
rapid advancement of computer technology. It
enables to evaluate in details the energy and spatial
distribution of neutrons and photons emitted after
fission reaction in a nuclear reactor. Key properties
such as criticality, decay heat, and radioisotope
production rate etc. can be deduced from theseneutronics calculations by these nuclear codes.
We are developing standard nuclear codes tosupport and advance the peaceful use of nuclear
energy and technology. The main codes we aredeveloping are MVP, MARBLE, and FRENDY. The
advancements of each code in 2018 JFY aresummarized below.
We are also collaborating tightly with nuclear data
center to validate the next version nuclear datalibrary JENDL-5, which will be processed andutilized in these nuclear codes.

Reference

1)
2)
3)
4)
5)

Y. Nagaya et al., JAEA-Data/Code, 2016-018, (2017).
https://rpg.jaea.go.jp/main/en/program_mvp/
K. Yokoyama et al., JAEA-Research, 2018-011, (2019).
K. Tada et al., JAEA-Data/Code, 2018-014, (2019).
https://rpg.jaea.go.jp/main/en/program_frendy/MVP

MVP realizes fast and accurate Monte Carlosimulation of neutron and photon transport
processes. The version 3 of MVP1) was released in2018 JFY and available from RIST in Japan andOECD/NEA data bank as NEA-1673 MVP/GMVP V.3.
The cross section library for MVP3 was produced as
MVPLIB2017 for user convenience from JENDL-4.0,
3.3, 3.2, JENDL/AC-2008, ENDF/B-VII.1, VII.0, VI.8,
JEFF-3.2, 3.1.2, 3.1, 3.0, 2.2 and MVP photo atomic,
photonuclear and dosimetry libraries. The
MVPLIB2017 can be downloaded from our group’s
home page.2)

MARBLE

MARBLE is a versatile reactor analysis code system.
The version 2 of MARBLE enables one to executealmost all analysis functions of the JAEA’s
conventional neutronics code system for fast
reactors with the unified user interface. By utilizing
this function of the MARBLE-2, a new unified crosssection set ADJ2017 has been developed3). The
ADJ2017 is based on JENDL-4.0 and adjusted using
a total of 620 integral experimental data set. The
ADJ2017 is expected to be utilized as a standard
database of FBR core design.

Fig.1 Role of FRENDY bridging nuclear data libraries
such as JENDL and various nuclear calculation codessuch as PHITSFRENDYFRENDY is a new nuclear data processing code. The
role of the code is schematically shown in Fig.1. It
enables to process nuclear data such as JENDL in
ENDF-6 format. Users can easily utilize the
FRENDY’s functions in their own codes. The firstversion of the FRENDY treats the ENDF-6 format
and generate the ACE files which is used forContact (Group Leader):Hideo HARADA
harada.hideo@jaea.go.jp
12

FY2018 NSEC Group Activity

Research Group for Nuclear Sensing
and improved. By using the NDA techniques, wehave been developing a new NDA systemcapable of quantifying fissile (U, Pu) masscontained in highly radioactive nuclear
materials2). In 2018, we mainly designed DDA
and PGA system using Monte Carlo simulations.
The DDA is one of active neutron measurement
technique based on active interrogation of
nuclear material samples by external neutrons.
The detection limit of the newly developed DDA
system for the analysis of a large sample such asa MOX can container (2 liter) was investigated by
the Monte Carlo simulation studies andexperimental tests. As the results, it was foundthat the DDA system could detect less than 10
mg of 239Pu, and the optimum thickness of thecylindrical HDPE polyethylene moderator isaround 3cm-5 cm3).
Although one of the main targets is a spent fuelwith a pellet shape, there is little knowledge of
how well NRTA determines the amount of SNMs
in a pellet fuel. In order to investigate the effectof the sample shape in the NRTA measurement,
NRTA experiments were made with simulated
spent fuel pellets (W, Ag, In, Rh) at a 10-mtransmission station of the GELINA facility of
EC-JRC in Geel. Measured transmission spectrum
clearly shows resonance dips derived from theindividual nuclei. The obtained abundances
agree with expected ones within 7.5%,
suggesting the potential of a compact NRTA
system to measure the amount of SNMs innuclear fuels4).
This research was implemented under thesubsidiary for nuclear security promotion of
MEXT.

Non-destructive analysis (NDA) is a key tool for
nuclear safeguards, nuclear security, nuclear
waste
management
andnucleardecommissioning. However, new and advanced
NDA techniques are still required to address
nuclear material accountancy of Special Nuclear
Materials (SNMs) and Minor Actinides (MA) inhighly radioactive nuclear materials, because
high levels of radiation make it very difficult tomeasure the amount of SNMs and MA.
Developments of low-cost, accurate and practical
NDA systems are also needed for effective
implementation. We have therefore developed
NDA system and related methodologies. The
following are a part of our group activities in
2018.

NDA system for the fuel debris

In decommissioning of Fukushima Daiichi
Nuclear Power Plant, material accountancy of
SNMs in fuel debris produced in the nuclear
accident is required. Since the fuel debris
contains many different materials, it is hard tomeasure SNMs. We have developed the Fast
Neutron Direct Interrogation (FNDI) method thatcan measure a variety of nuclear materials
nondestructively with reducing the inﬂuence ofsample matrices. In order to quantify theamount of SNMs in the fuel debris, we designed
a measurement system based on the FNDI
method. In particular, we developed a fast
response detector bank for fast neutron
measurements using Monte Carlo simulations.
The new detector bank has more than one orderof magnitude faster response compared to thestandard ones. Then we evaluated thenondestructive measurements of SNMs in thefuel debris. The results show that SNMs in thefuel debris can be measured accurately in manycases because the influence of the sample
matrices can be reduced by using the designed
system1).

Reference

1) M. Maeda et al., J. Nucl. Sci. Tech., Vol56, 617-628,
20192) Y. Toh et al., Proceedings of INMM 59th Annual
Meeting, 2018
3) A. Ohzu, et al., Proceedings of the 2018 IEEE NSS &MIC conference record, Sydney, 20184) H. Tsuchiya, et al., Proceedings of INMM 59th Annual
Meeting, 2018

NDA system for nuclear security

With the aim of establishing an active neutron
NDA system for useful applications in the field of
nuclear non-proliferation and nuclear security,
active neutron NDA techniques: Differential
Die-Away Analysis (DDA), Prompt Gamma-ray
Analysis (PGA), Neutron Resonance Capture
Analysis(NRCA),
NeutronResonance
Transmission Analysis (NRTA) and Delayed
Gamma-ray Analysis (DGA), have been studied

Contact (Group Leader):Yosuke TOH
toh.yosuke@jaea.go.jp
13

FY2018 NSEC Group Activity

Research Group for Corrosion Resistant Materials
3.53. We concluded that acidification occurred in atight crevice and resulted in localized corrosion ofstainless steel.

We have been researching on corrosion of metalmaterials used for nuclear facilities. If the corrosion
occurs, the components of the nuclear facility will
degrade, which may cause holes and cracks.
Therefore, we are focusing on the corrosion
mechanism to develop the methods of corrosion
prediction and prevention. Through these research
activities, we contribute to improving the reliabilityof nuclear facilities.

Reference
1)

2)

E.Irisawa et.al., J. Nuc. Sci. and Tech., 56, 337–344,(2018).
Y.Soma et.al., Zairyou-to-Kankyo, 67, 381-385, (2018).

Researches on corrosion
mechanisms of nuclear fuelreprocessing plant materials

Reprocessing plant materials will be corroded
intricately by the reprocessing solution whichcontaining severe corrosive nitric acid and several
varieties of highly oxidizing metallic cations derived
from spent nuclear fuels. The critical factor for the
corrosion is "re-oxidizing" behavior of the cations.
These cations cause intergranular corrosion in
stainless steel because oxidizing cations shift thecorrosion potential to noble (Fig.1). The reoxidation rate constants of oxidizing cations, such
as Cr, V, Pu, and Np, were analyzed and werediscussed in terms of the effect on timedependencies of the corrosion rate. Our data
showed that the cations with a high re-oxidation
rate constant, such as Np, could keep the corrosion
rate at a significant level continuously for the long
immersion duration.

Researches on corrosion
mechanisms of Boiling
Reactor (BWR)

Fig. 1 Polarization curves of SS (SUS310Nb) in theboiling 3 M-HNO3 containing oxidizing cations1).

Water

Fig. 2 Schematic illustration of crevice specimen
with sensors.

Stainless steels (SS), such as type 316L, show stresscorrosion cracking susceptibility in boiling water
reactor environments. It’s important to understandthe corrosion behavior of the crack tip in order tomake the mechanism of SCC clear. The in-situ
measurement of electrical conductivity of solution
within crevice of type 316L in 288 °C water has been
conducted with a newly developed electrochemicalsensor system. The sensor consists of an electrode(φ ≈250 μm stainless steel) and an insulator (highpurity alumina) directory imbedded into crevice
former plate. The sensors were installed at different
positions within tapered crevice of SUS316L(Fig.2).
The sensor measures local electrical conductivity(k) of crevice solution beneath the electrode withelectrochemical impedance method. At sensor-A
position with gap ≈ 4.4 μm, k increased with timeand localized corrosion occurred in the vicinity ofthis position (Fig.3). Thermodynamic equilibrium
calculation based on oxide in the crevice showedthat the pH value of crevice solution can reach toFig. 3 Change in κ as a function of time in 288 °C
pure water with 32 ppm concentration on
dissolved oxygen.2)

Contact (Group Leader):Chiaki KATO
Kato.chiaki16@jaea.go.jp

14

FY2018 NSEC Group Activity

Research Group for Radiation Materials Engineering
We are conducting several kinds of researches todeepen the understanding of material
degradation mechanism under radiation
environment. A study on stress corrosion
cracking (SCC) of low carbon austenitic stainlesssteel (SS) is one of the representative research
topics in our research group. This researchsubject is still recognized as a significant issue onmaterial degradation because some crucial
questions remain unanswered. Besides, we arealso making the most use of computational
atomistic simulations to clarify the unrevealed
mechanism of material deterioration.

by dislocation nucleation from the GBs.
Reference

1) S. Aoki, et al., “Effect of long-term thermal aging on
SCC initiation susceptibility in low carbon austenitic
stainless steels“, Proc. 18th International Conference on
Environmental Degradation of Materials in Nuclear
Power Systems –Water Reactors, p.1879, Springer(2018)-Published 7 October 2017.
2) T. Tsuru, “Origin of tension-compression asymmetry inultrafine-grained fcc metals”, Phys. Rev. Materials 1,033604-Published 9 August 2017.

Unanswered questions on SCC

In spite of extensive studies on SCC in low carbon
SSs, the initiation and propagation mechanisms
have not been fully understood yet. The
depletion of Cr concentration in the vicinity ofgrain boundaries (GBs) is considered to be themain cause of the standard grade of SS. However,such sensitization phenomenon was notconfirmed irrespective of the investigation of a
Type 316L SS sample extracted from a cracked
core shroud of a Japanese boiling water reactor.
In order to approach the degradation mechanism
such as cracking occurred in low carbon SSs, theeffect of long-term thermal aging (LTA) on SCC
initiation susceptibility was investigated using
Type 316L SS with different material parameterssuch as cold working (CW) and LTA. Figure 1
showed the number of surface cracks initiatedduring creviced bend beam (CBB) testing at
288 °C for 1000 hours. Type 316L CW
demonstrated resistance to cracking, whereas
Type 316L CW + LTA indicated the high SCC
initiation susceptibility [1].

Fig.1 Number of surface cracks in Type 316L SS
initiated during CBB testing.

Computational materials sciencebased on atomistic simulation

A mechanism of anomalous tension-compression(T-C) asymmetry in ultrafine-grained (UFG)
aluminum (Al) and copper (Cu) is proposed usinglarge-scale atomistic simulations and dislocation
theory. Unlike coarse-grained metals, UFG Al
exhibits remarkable T-C asymmetry of the yieldstress. Figure 2 showed stress-strain curves and
T-C asymmetry in UFG Al and Cu with different
dislocation densities under uniaxial stress. The
yield stress σy was defined as the maximum
stress in these curves. The yield stress decreased
with increasing dislocation density under bothtension and compression [2]. The atomistic
simulations reveal that the yield event is not
related to intergranular dislocations but caused

Fig.2 Stress-strain curves and T-C asymmetry in
UFG metals: (a) Cu under tension, (b) Cu undercompression, (c) Al under tension, and (d) Al
under compression.

Contact (Group Leader):Shinichiro YAMASHITA
yamashita.shinichiro@jaea.go.jp
15

FY2018 NSEC Group Activity

Research Group for High Temperature Science on Fuel Materials
We treat issues on nuclear fuel materials for lightwater reactors and advanced reactors in the
future. Experimental works on uranium and nonradioactive surrogate materials are performed in
the Research Building No. 4 with various heating
devices, analytical equipment, and material
property measurement apparatus. Those ontransuranium elements (TRU: Pu and minor
actinides) are performed at the TRU-HITEC in
NUCEF, consisting of specially designed hot cells
and glovebox with highly purified argon
atmosphere. We also take advantage ofcomputer science to understand or predict
phenomena concerning the fuel materials. Fuelperformancecode
andthermodynamic
calculation code are strong tools, so we makesustained efforts to upgrade the fuel material
properties database and thermodynamic
database having high practicality.

have been studying on characteristics of the fueldebris from the aspects of laboratory scale
experiments and thermodynamic evaluation. Theinteraction tests between UO2 and Zr were
performed at around 2173 K using UO2 crucible
and Zr metal pellet. From the results of thesurface microanalysis, we explained themechanisms of uranium diffusion and fueldegradation from thermodynamic perspective(Fig. 2).2)
Reference

1) M. Takano, “Material challenges for future nuclear fuelcycles –R&D on nitride fuel cycle for MA
transmutation,“ NuMat 2018, Oct. 2018, Seattle.
2) N. Shirasu, M. Kurata et al., “High-temperatureinteraction between zirconium and UO2,” in proc. FDR
2019, paper No. FDR2019-1067.

R&D on MA transmutation fuelFor the volume and radiotoxicity reduction in thehigh-level radioactive wastes, partitioning andtransmutation of minor actinides (MA: Np, Am,Cm) are key technologies. We have been
engaged in R&D on the MA-bearing nitride fuelfor accelerator driven system (ADS) as our main
mission in these two decades. The potential fuelforms are (MA,Pu,Zr)N single phase solid
solution pellet or (MA,Pu)N/TiN dispersion pellet,
in which ZrN and TiN are inert matrices to dilute
TRU. Since 2016 a big project “R&D on nitride
fuel cycle for MA transmutation to enhancesafety and economy” has been carried out by acompetitive fund of the MEXT through FY2019.
This project covers the elemental technologies
needed for engineering scale fuel fabrication andthe fuel behavior data needed for safety analyses
under irradiation. The annual topic on fuelfabrication in 2018 is the sol-gel process to
obtain sphere particles of the oxide and finecarbon powders as precursor for carbothermic
nitridation. By using Dy as surrogate material,
the appropriate process parameters such as feedsolution composition, viscosity, dropping nozzle
size, and frequency were determined. These
results enabled us to obtain excellent shape ofparticles with controlled diameter (see Fig. 1).
Details of the R&D project and progress were
presented at NuMat 2018 international
conference as an invited lecture.1)

Fig.1 Dy2O3+C mixed particles (φ 0.33 mm)
calcined from the gel particles (φ 0.47 mm).

Fig.2 Cross section of test piece and ternary phase
diagram of U-Zr-O system at 2173 K.

Contact (Group Leader):Masahide TAKANO
takano.masahide@jaea.go.jp

Thermodynamics of fuel materials

In order to contribute to decommissioning of the
Fukushima Daiichi Nuclear Power Station, we

16

FY2018 NSEC Group Activity

Research Group for Radiochemistryorganic or aqueous phases, so that the Eu3+
structure at the interface is unique.
ReferenceRadiochemistry provides fundamental information
about the essential materials in developing nuclear
technology by identification of the chemical
reaction of radioactive materials by measurement
and chemical separation. We chemically resolve
various issues arisen from nuclear industry by
developing new technique of measurement andcomputational method.

1) Kumagai, Y. et al., Journal of Nuclear Materials, vol.497,
p.54–59, 2017.
2) Kusaka, R. et al., Physical Chemistry Chemical Physics,
vol.20, issue 4, p.2809–2813, 2018.

Chemical Reactivity of Nuclear FuelWe have shown that uranium dioxide (UO2)
becomes chemically stable by forming solid
solution containing zirconium (Zr). The stabilization
by Zr indicates that the molten fuel debris in
TEPCO’s Fukushima Dai-ichi Nuclear Power Plants(1F) would be stable against dissolution by chemical
reactions and would remain in the reactors until it
is retrieved.
The results on the dissolution of U in the simulated
fuel debris by H2O2 are shown in Fig.11). It issignificantly inhibited by the incorporation of Zr. In
this experiment, U oxide containing Zr was used assimulated fuel debris, because the fuel debris is
expected to contain Zr by melting with the fuelcladding material. When the simulated debris was
exposed to H2O2, the reaction of H2O2 proceeded at
a rate comparable with that of UO2. However, thedissolution of U was significantly inhibited (Fig.1).

Fig.1 Comparison of the H2O2 reaction kinetics
between UO2 and the simulated fuel debrisInterfacial
Spectroscopy
for
Nuclear Engineering Chemistry

We have been developing advanced laser
spectroscopy, so-called Sum Frequency Generation(SFG) spectroscopy which can identify the chemical
structure on the surface and interface in thematerials. In the nuclear industry, solvent
extraction is one of the promising chemical
techniques for isolating specific elements in such asradioactive waste or spent nuclear fuel. We address
the SFG to improve the efficiency of solvent
extraction. As a representative example of common
solvent extraction system, for instance, theinterface vibrational spectra of extraction of
europium ions (Eu3+) using di-2-ethylhexyl
phosphate extractant (HDEHP) were obtained(Fig.2)2). As the concentration of Eu3+ increases, thepositive sign of the water signal becomes negative.
Positive and negative indicates that interfacial
water molecules pointing upward (hydrogen-up)change to a downward (hydrogen-down)orientation as Eu3+ is adsorbed to the interface.
That is, interfacial water molecules are bonded toEu3+ with hydrogen-down orientation (Fig.2). The
structure of Eu3+ sandwiched between HDEHP andwater molecules has not been reported so far in theFig.2 Vibrational spectra of the interface obtained byadvanced laser spectroscopy: heterodyne-detectedvibrational sum frequency generation spectroscopy

Contact (Group Leader):Masayuki WATANABE
watanabe.masayuki@jaea.go.jp

17

FY2018 NSEC Group Activity

Research Group for Analytical Chemistry
amorphous hydroxide to crystalline oxide. As
chemical form affect the aggregation of particles, it
is important factor for elucidation of the migration
behavior in environmental water.

Accurate analyses of radioactive substances arefundamental technologies supporting the nuclear
usage. Removal of interference elements prior to
instrumental analysis and control of the chemical
state of the analyte are key techniques for the highprecision chemical analysis. The research group for
analytical chemistry is developing practicalanalytical methods for actinide and fission products
based on studies of elucidation of chemical reaction
and ion separation phenomena such as adsorption,
precipitation, aggregation, etc.

Reference

1) Asai et.al., Talanta, 185, 98-105, 2018
2) Asai et. al., Anal. Bioanal. Chem., 411, 973–983, 2019

Radioanalytical chemistry

We have been committed to the development of awide range of analytical techniques for thedetermination of long-lived radionuclides.
Estimating the risks associated with radiation fromlong-lived radionuclides in radioactive waste is
essential to ensure the long-term safety ofpotential disposal sites. Our research focuses ondeveloping analytical techniques based on
inductively-coupled plasma mass spectrometry(ICP-MS) along with its preparation procedures
using solid phase extraction (SPE) materials. We
utilized an in-house microvolume SPE cartridge forthe sample preparation of ICP-MS determination of
93Zr1), achieving rapid and reliable measurement(Fig. 1). Another research interest is laser ablation(LA), one of the hyphenation techniques to ICP-MS,
allowing direct measurement of a solid sample. We
employed LA-ICP-MS to 107Pd determination2) (Fig.
2). The solid Pd sample was obtained as precipitate
by laser-induced photo reduction. These unique
techniques have a capability to reduce operatingtime, radiation exposure to workers, and secondary
waste.

Fig. 1 Microvolume SPE cartridge
The Zr separation can be completed by 1.2 min.
Almost all other elements originally contained in the
spent nuclear fuel sample have been removed.

Electrochemistry of Actinide

In the decommissioning of Fukushima Daiichi
Nuclear Power Plant, there is concern about
internal exposure due to scattering of alphanuclides contained in debris. In order to predict
transfer of the radionuclides into the contaminatedstagnant water, it is necessary to accurately
understand the chemical state and reaction of theradionuclides in the water of environmental
condition. Redox of actinide ions in weakly acidic
solution is complex reaction due to the formationof precipitate. We tried to elucidate their reaction
mechanism by electrochemical impedance
measurement. Electric resistances of the electrodesurface covered with the uranium and neptunium
deposits exhibit a change in chemical form from

Fig. 2 Direct measurement of 107Pd by LA-ICP-MS

Contact (Group Leader):Yoshihiro KITATSUJI
kitatsuji.yoshihiro@jaea.go.jp
18

FY2018 NSEC Group Activity

Research Group for Environmental Sciencedispersion simulation showed that most of thattransferred to the ocean by direct release ordeposition from the atmosphere existed in thesurface layer (0 to 211 m from the sea surface)shortly after the 1F accident. However, as time
passed, it was transported from the surface layer
to deeper layers (Fig.2). The 137Cs amounts in thesurface, intermediate (211 to 510 m), deep (510
to 1,050 m), and bottom layers (deeper than
1,050 m) one year after the 1F accident were 71,
19, 4, and 0.8 % of the total release amount,respectively.
This study suggests that the accident-derived
137Cs was dispersed widely into the North Pacificand gradually dispersed from the surface to thedeeper layers, regardless of the different
ocean-current data.

We are conducting research and development inorder to upgrade the migration and assessment
technology of environmental radioactive
materials, required for environmental impact
assessment of various radionuclides releases andenvironmental pollution events. As anapplication to the global environmental problem,
we participate in the project "Climate Change
Research Using Nuclear Science and Technology"of the Forum for Nuclear Cooperation in Asia
(FNCA), and leading the research in Japan.

Prediction of the dispersion ofradionuclides released into theocean

Cesium-137 was released to the ocean by theaccident at the Fukushima Daiichi Nuclear Power
Station (1F) of the Tokyo Electric Power Company
Holdings, Inc. In this study, we applied theoceanic-dispersion
model(SEA-GEARN)
developed at JAEA. Input oceanic data were
calculated by oceanic general-circulation modelsof the Japan Marine Science Foundation (JMSF),
the Japan Agency for Marine-Earth Science andTechnology (JAMSTEC), the MeteorologicalResearch Institute (MRI) of the Japan
Meteorological Agency (JMA), and the National
Oceanic and Atmospheric Administration (NOAA).
The data-assimilation method was applied tothese oceanic general-circulation models to
assimilate observed data into numericalsimulations. The direct-release rate of 137Cs into
the ocean was estimated using the observed sea
surface 137Cs concentrations near the northernand southern discharge channels of 1F. To
provide the 137Cs-deposition amounts at the sea
surface, we conducted an atmosphericdispersion simulation using the latest-estimated137Cs release rate into the atmosphere.
Compared to the simulation with a lower
horizontal resolution, the higher-resolution
137Cs
simulation
reproduced welltheconcentration observed in the coastline andoffshore of Fukushima prefecture. The 137Cs was
suggested to have been spread along the coast in
the north–south direction during the first few
months after the 1F accident. The simulations forthe western part of the North Pacific and thewhole North Pacific reproduced the main ocean
current favorably using the data-assimilation
method, despite the relatively low resolution.
This suggests that the Kuroshio Extension plays alarge role in the transport process of 137Cs fromthe coast to the outer ocean (Fig.1).
Analysis of the depth distribution of 137Cs by the

Reference

1) Kawamura, H. et al., Journal of Environmental
Radioactivity, 180, 36–58, (2017).

Fig.1 Averaged surface 137Cs concentrations in
April 2011

Fig.2 Time series of the ratios (%) of 137Cs amounts
at the calculation domain

Contact (Group Leader):Takuya KOBAYASHI
Kobayashi.takuya38@jaea.go.jp
19

FY2018 NSEC Group Activity

Research Group for Radiation Transport Analysis
analyses of radiation dose to an aircraft crew due
to a solar flare event 2). The improved system candetermine the model parameters to characterize
the profiles of ground level enhancement (GLE)event, when GLE event is detected. The
performance of the system was examined byanalyses of major GLE events in the 21st century.
This study is carried out under collaboration withother institutes and universities and partially
supported by JSPS KAKENHI grants (26106006,
15H 05813, 15H05815, 16H01180, and 17K05671).

Nowadays, a computer simulation technique that
can analyze radiation transport in a material isessential for research and development in thefield of nuclear and radiation sciences. We
develop a radiation transport simulation code,
Particle and Heavy Ion Transport code System(PHITS), and apply it to industrial, scientific, andmedical studies. In addition, we also conduct
studies on radiation protection and effects.

Upgrade of PHITS code

PHITS has been upgraded to improve its
reliabilities and expand areas to be applied. In
FY2018, we released PHITS versions 3.08 and3.10. The major upgraded features for these
versions are as follows. Please access PHITS
homepage 1), if you have an interest in further
information on the latest edition.
/ High energy nucleus-nucleus interaction model(JAMQMD2) is developed and implemented.
/ Neutrino interaction model is newly developedand implemented.
/ We establish a procedure for coupling PHITS withthermal analysis software such as ANSYS.
In recent years, “Track-structure Mode” has beendeveloped to consider all ionization andexcitation events explicitly, in addition toaveraged energy deposition that has been
calculated by many users. Track-structure Modeis available for electron and positron in thecurrent version of PHITS. In FY2018, we haveupdated the mode to be applied to proton andall kinds of carbon ions. The updated mode can
explicitly simulate carbon ion track in water andplot the position where ionization and excitation
events might occur (Fig.1). We will implement
the updated mode to a future version of PHITS.

Internal dosimetry for insolublecesium-bearing particles

Lung absorbed dose (mGy)

An insoluble cesium-bearing particle withradioactivity can move as a single particle in ahuman body after intake of these particles. In
this case, it is impossible to estimate the numberof radioactive cesium disintegrations in the bodyby an existing method in which the averagebehavior of countless nuclei in the body is taken
into account. Then, a new method wasdeveloped to simulate the behavior of theparticle in the body stochastically 3). We derived
internal doses based upon the number ofdisintegrations calculated by the developed
method. As a result, uncertainty originating in
the insolubility of cesium particles was negligibly
small for the exposure level of 1 mGy in lungabsorbed dose (Fig.2).
101
100

10-1
10-2
10-3
10-4
10-5
10-6

10-7
100

99th percentile value
Arithmetic mean
Median101
102
103
Number of inhaled particles

104

Fig. 2 Variation of lung dose with thenumber of inhaled particles
Reference

1) PHITS homepage, https://phits.jaea.go.jp/
2) T. Sato et.al, Space Weather, 16(7), p.924 - 936, (2018).
3) K. Manabe et.al., J. Nucl. Sc. Technol., 56(1), p.78 – 86
(2019).

Fig.1 C6+ ion track around 1 MeV/u in water.

Contact (Group Leader):Fumiaki TAKAHASHI

Development of WASAVIESWe improved WASAVIES (WArning System for
AVIation Exposure to Solar energetic particles(SEP)) to be capable of real-time and automatic

takahashi.fumiaki@jaea.go.jp20

FY2018 NSEC Group Activity

Development Group for Thermal-Hydraulics Technology
radioactive aerosol by water droplets, the direct
observation method of the capturing behavior wasdeveloped, and observed the capturing behavior of
the particles to consider the removal mechanisms.
We proved that an inertial impact of aerosol
particles to a droplet occurs as one of physicalmechanisms of removal radioactive aerosol by theabove Venturi scrubber.

For the establishment of thermal-hydraulics
numerical simulation method for large-scale twophase flow and multi-phase flow, we are developing
two-phase flow and multi-phase flow numericalsimulation codes for large-scale computers, TPFIT
and JUPITER (please see the highlight), performing
thermal-hydraulics experiments to constructvalidation databases and developing measurement
techniques to obtain detailed thermal-hydraulics
data. These developed techniques are applied to
the research works for improving the safety of the
LWRs and considering the decommissioning
process of the Fukushima-Daiichi nuclear power
station.

2)

TPFIT

3)

Reference

1)

TPFIT (Two-Phase Flow with Interface Tracking) isdeveloped in JAEA for two-phase flow analysis inreactor systems, and can be applicable tocomputational fluid dynamics simulation including
two-phase flow in any systems. TPFIT adopts theadvanced interface tracking method, and can beapplied to the detail numerical simulation of twophase flow including movement and deformationof the interface.
As one of examples, the process of bubble
coalescence in boiling phenomena for light water
reactors was simulated in this method (Fig.1) 1). This
numerical study contributed the establishment of aphysical model to predict the critical heat flux.
TPFIT can be also applicable to high-speed
compressible two-phase flow, such as two-phaseflow in Venturi scrubber, whose maximum velocity
is more than 150 m/s. In the snapshot of numericalresults, small droplets in high velocity gas flow were
simulated directly (Fig.2). Recently, TPFIT has beenreleased at PRODAS2).

A. Ono et al., Proceedings of 12th International Topical
Meeting on Nuclear Reactor Thermal-Hydraulics,
Operation and Safety (NUTHOS-12), No.1068, (2018).
2) PRODAS (PROgram and Database retrieval System),
http://www.rist.or.jp/nucis/
S. Uesawa et al., Proceedings of 12th International
Topical Meeting on Nuclear Reactor ThermalHydraulics, Operation and Safety (NUTHOS-12), No.964,
t=2.0 mst=4.0 mst=6.0 mst=8.0 ms

t=10.0 ms

t=12.0 ms

Fig.1 SIMULATION OF BUBBLE COALESCENCE
Water

Water film

Gas
150 m/s
Water

Experiment and measurement

Gas

Water

150
m/sWaterIn addition to developing TPFIT and JUPITER, ourresearch group performs various experiments tovalidate those simulations and construct basic
physical models. As one of experiments, we
perform the thermal-hydraulics experiment of
Venturi scrubber3). The Venturi scrubber is one of
the components of the filtered venting systems andremoves fission products in venting gas under severaccidents. We have performed the visualize
experiment of two-phase flow and the numericalsimulation with TPFIT to understand the detailed
decontamination mechanism (Fig.2). In addition, toelucidation of the removal mechanism of

Water film
5 mm

Fig.2 TWO-PHASE FLOW BEHAVIOR IN VENTURISCRUBBER(TOP: SIMULATION, BOTTOM: EXPERIMENT)(2018).

Contact (Group Leader):Hiroyuki YOSHIDA
Yoshida.hiroyuki@jaea.go.jp
21

FY2018 NSEC Group Activity

Development Group for LWR Advanced technology
chemisorption model in ECUME to the SA analysis
code. It is expected to result in more accurate
estimation of Cs amount retained in reactor
pressure vessel of 1F.

We are conducting a fundamental research on LWR
advanced technology to provide fundamental
knowledge for the improved safety performance of
LWR by contributing to improving the scientificrationality for regulation standard, safety margin
enlargement for accident management design, anddecommissioning and dismantling of Fukushima
Dai-ichi Nuclear Power Station (1F). Main research
themes are the fission product (FP) behaviors, andfuel/material behaviors under conditions fromnormal operation to severe accident (SA).

Accident tolerant fuel (ATF)

For the reduction of the accident risk and thefurther improvement of safety of the existing LWRs,
ATFs with higher reliability are being developedwith a focus on enhanced tolerance to hightemperature steam under SA. FeCrAl steel
strengthened by the dispersion of fine oxide
particle for BWR and SiC fiber reinforced SiC matrix
composite (SiC) for BWR and PWR were selected as
major ATF cladding concepts. SA analyses are
performed for PWR with SiC fuel cladding in order
to confirm the advantage of SiC fuel cladding
compared to current fuel cladding in terms of time
to core melt and hydrogen generation2. In the SA
analyses, small break LOCA sequences are selected
because of dominant sequences of PWR. According
to the SA analyses using the MELCOR code, the timeof the core melt for SiC fuel cladding is delayed afew hours compared to current fuel cladding. The
hydrogen generation for SiC fuel cladding is also
reduced compared to current fuel cladding as
shown in Fig.2. Hence the merit of SiC fuel cladding
is shown for small break LOCA sequences.

Fission product behavior

We are conducting a fundamental research on FP
behavior in a reactor during LWR SA. The objective
is to construct a database of FP chemistry named
ECUME (Effective Chemistry database of fission
products Under Multiphase rEaction)1. ECUME
consists of dataset for chemical reaction kinetics,
elemental model set, and thermodynamic dataset.
ECUME is being constructed based on systematic
experiments and analyses by using uniqueexperimental apparatus (TeRRa, CREST) andanalysis tools (CHASER) (Fig. 1). The TeRRa can
reproduce temperature profiles and steam
environment in a reactor during LWR SA. The
CHASER is based on the 3D-CFD analysis tool, which
can make the analysis of FP transportation with finespace resolution possible. These experiments andanalyses can provide data on detailed andconsecutive FP chemistry during transportationfrom reactor core to environment in LWR SA.

*This study was funded by Ministry of Economy, Trade andIndustry (METI) of Japan.

Fig.2 Hydrogen generation mass for current fuelcladding and SiC fuel cladding2

Fig.1 Experimental apparatus and analysis tool for
more detailed simulation of FP behaviors

Reference
1)
2)

ECUME can be reflected to the improvement ofphysical/chemical models applied to a SA analysis
code. ECUME covers important phenomena
revealed after the 1F SA, namely effect of BWR
control material boron on cesium (Cs) and iodine
chemistry, chemical reaction of Cs with structural
materials (Cs chemisorption), and Cs aerosol
behavior at reactor building. As an example ofpractical application, we incorporated the Cs

S. Miwa et al., Proc of ICONE-27, ICONE27-1993, (2019).
Y. Yamakoshi et al., Proc of TOPFUEL2018, A0076 (2018).

Contact (Group Leader):Masahiko OSAKA
ohsaka.masahiko@jaea.go.jp
22

FY2018 NSEC Group Activity

Research Group for Partitioning
the outside of the extraction solvent. The
calculation indicated that the influence of beta-ray
and gamma-ray transmitted from the nuclides in
the feed solution contacted to the extraction
solvent could not be disregarded.
N,N,N’,N’,N’’,N’’-Hexaoctyl-nitrilotriacetamide(HONTA) is one of the extractants complied with
CHON principle. HONTA was proposed as an
extractant to separate MAs from REs in SELECT
process, and the effect of gamma-ray irradiation on
HONTA was studied. Dioctylamine, dioctylformamide, and dioctylacetamide were observed
as the main degradation products after irradiationof gamma-ray by a 60Co source. From theconcentration change of HONTA with respect to theabsorbed dose (Fig. 1), the decay constant and theG-value for the degradation of HONTA wereobtained as 2.8 × 10-6 Gy-1 and 0.37 μmol/J,
respectively.
Using the calculated absorbed dose and theobtained G-values, the radiolysis of the extractant
in SELECT process could be predicted quantitatively.
Reference

Our research group has been developing
partitioning processes by hydrometallurgicalmethod as one of measures for managing high-level
radioactive liquid waste (HLLW) generated from
reprocessing of spent nuclear fuels.

R & D on SELECT process

Separation performance of partitioning processes
depends largely on the extractants used in eachprocess. Many extractants have been developed
and/or studied in our research group and some ofthem extracted target metals effectively. Amongthese extractants, we have focused on theextractants that comply with CHON principle(extractants consisted of carbon, hydrogen, oxygen,and nitrogen atoms), and have proposed ahydrometallurgical method called SELECT (Solvent
Extraction from Liquid-waste using Extractants of
CHON-type for Transmutation) aiming at recycle
use of nuclear materials and separating actinides
for transmutation. We have performedexperiments with genuine HLW and radioactive
nuclides such as U, Pu, Am, and Cm in a hot cell
and/or glove boxes. The obtained results havesupported the validity of SELECT process from theviewpoint of the separation performance of metalelements. The extractants used in SELECT process
are exposed to high radiation dose, and thus wehave been conducting the studies on radiation
effect to develop practical separation processes.

1) T. Sato et al., J. Nucl. Sci. Technol. 55, 684-690 (2018)2) T. Toigawa et al., “Simulation of energy transfer toextraction solvent by radiation in minor actinides
separation process”, 15th OECD/NEA Information
Exchange Meeting on Actinide and Fission ProductPartitioning and Transmutation (IEMPT-15), UK (2018)3) T. Toigawa et al., “Gamma Radiolysis of an Extractant for
Minor Actinides, HONTA, in Dodecane Diluent”, QST
Takasaki Annual Report 2016, 74(2018)

Radiation effect on SELECT process

Extraction solvents will receive radiation energy
from various kinds of radioactive nuclides during
the separation. To evaluate the radiation effects in
SELECT process, the radiation energy transfer to theextraction solvent should be evaluated in terms ofeach radiation type emitted from the radioactive
nuclides. Monte Carlo Particle Transport code
(PHITS) was employed to calculate the doseabsorbed by an extraction solvent containing adiclycolamide which was proposed as an extractant
to recover minor actinides (MAs) and rare earths(REs) from HLLW in SELECT process. The dose rate
to the extraction solvent during the separation was
estimated up to 3.16 kGy/h by the calculation, of
which 2.60 kGy/h was due to energy deposition by
primary and secondary electrons corresponding to
low LET radiations. It is well known that
diglycolamide compounds also extracts beta-ray
emitters such as Y and Pm, however, the dose rates
of 1.07 kGy/h in mixing part and 0.301 kGy/h insettling part were due to the radiation came from

Fig.1 Effects of absorbed dose on concentrationof HONTA.

Contact (Group Leader):Tatsuro MATSUMURA
matsumura.tatsuro@jaea.go.jp
23

FY2018 NSEC Group Activity

Research Group for Nuclear Transmutation System(LEU)/Pb systems was constructed1). The validation
in LEU/Pb system was successfully done as shownin Fig.2, while that in HEU/Pb system needs further
investigation. HEU/Pb system was re-examinedwith a new device that can guarantee the gap
reproducibility with a higher accuracy and precision.
Furthermore, construction of plutonium (Pu)/Pb
system has been completed using two kinds ofplutonium plates from the Zero Power Physics
Reactor (ZPPR). We will valuate Pb cross sections
systematically using these data obtained in various
systems and confirm availability of present Pb
nuclear data for ADS design.

Research Group for Nuclear Transmutation System
is developing Accelerator Driven System (ADS)
devoted to transmutation of Minor Actinide (MA)
into short-lived or stable nuclide. Present R&D level
on ADS is at maturing of conceptual design andtesting by small-scale equipment for eachcomponent and material. To improve ADS design,
we are developing analysis system consisting ofparticle transport, thermal-hydraulics, material andplant behavior.
As small-scale R&D, we areconducting validation of nuclear data for particle
transport analysis using zero-power reactor.

Validation of nuclear data for ADS

Nuclear data of probability of reactions between Pb
and neutron is important for ADS design in whichhuge amount Pb is used as coolant coupled with Bi.
It can be validated by measuring difference of
criticality between two core configurations: withand without Pb region. The difference is called leadvoid reactivity worth. To measure it, a series ofintegral experiments are conducted as part of acollaboration with the Los Alamos National
Laboratory in the United States. In this series
experiment, several different experimental systemsof fuel composition were examined on the Comet(Fig.1) critical assembly of the National Criticality
Experiments Research Center. To provide
systematical data for validation, a high-enricheduranium (HEU)/Pb and a low-enriched uranium

Fig.1

Reference

1) M. Fukushima, et al., “Lead Void Reactivity Worth in
Two Critical Assembly Cores with Differing Uranium
Enrichments”, Nuclear Sci. Eng. 189, 93-99 (2018).

Contact (Group Leader):Kenji NISHIHARA
nishihara.kenji@jaea.go.jp

Comet

Comet is zero-power reactor
consisting of thin disks of fuel(U, Pu) or moderator (Pb, Al,etc.). Disks are replaced toeach other and criticality
differences, i.e. reactivity
were measured.
(National Criticality
Experiments Research Center(https://www.nnss.gov/pages/facilities/NCERC.html))

Fig.2 Comparison of experimental and calculated lead-void-reactivity
worth in the LEU/Pb systems

The results of this series experiment appear as green triangles（▲）.
The analytical results using the evaluated nuclear-data librarydeveloped by JAEA (Japanese Evaluated Nuclear Data Library, JENDL4.0) and the United States (Evaluated Nuclear Data File/B-Versions,
ENDF/B-VII.1) are indicated as red circles（●） and blue squares（■）, respectively. In the LEU/Pb systems, the experimental andanalytical results overlap, indicating good agreement.

24

FY2018 NSEC Group Activity

Research Group for MA Transmutation Fuel Cycle
decreasing the impurities existing in the product.
Nitride formation reaction of 2 wt.% Gd-Cd alloys
was studied using an apparatus developed for
100 g-Cd scale nitridation tests. Experiments
were carried out by heating the alloy sample
under vacuum at 693 K to distill Cd, followed byheating in N2 gas flow at 1073 K for nitridation.
The product having small amounts of anintermediate compound GdCd2, was crashed andheated again in vacuum followed by in N2 gas
flow to obtain pure GdN (Fig. 2), in which thecontent of Cd impurity decreased to 0.07 wt.%
[1].

Feasibility study on transmutation system showsthat only 20 % of minor actinides (MA) in the fuelcan be transmuted in one burning cycle of about
2 years. To increase the transmutation ratio,
reprocessing of spent MA transmutation fuels
and reuse of MA elements existing in the spent
MA transmutation fuels are necessary. Therefore,
fuel fabrication, transmutation, and reprocessing
should be repeated in the MA transmutation fuelcycle. We have been carrying out research anddevelopment of the technology on reprocessingof spent MA transmutation fuel to recover andreuse MAs in the spent fuels. One of ourconcerns is on pyrochemical treatment
technology, in which molten salts and liquid
metals are used as solvents; this technique issuitable for treatment of MA transmutation
nitride fuels.

Reference

1) H.Hayashi et.al., Recent Progress on Development of
Pyroprocessing Technology for Minor Actinide
Transmutation Nitride Fuels, Proc. Global2019 (2019).

Electrorefining process

Detailed design study of the flowsheet for theelectrorefining process of spent MA nitride fuelwas carried out [1]. The flowsheet contains therecycling process of the molten salt used in theelectrorefiner (Fig.1). Multistage counter current
reductive extraction using molten salt/Cd phases
and zeolite treatment of the molten salt areincluded in the salt recycling process which aims
at removing FP elements from the molten saltbath to keep the purity of the actinides
recovered in Cd cathode. The processparameters were determined to meet the target
recovery yield of MAs (> 99.9 %) which is one of
the condition enable to transmute 99 % of MA
contained in high level waste (HLW). The othertarget is the acceptable impurity level of rareearth (RE) fission products in the recoveredmaterial (RE/MA < 5 wt.%). Our study shows that
it is possible to meet the targets by purifying
2-3 % from 1000 kg molten salt in theelectrorefiner.

Intensity（a.u.）

Fig.1 A detailed flowsheet for the electrorefining
process.

Renitridation process

The nitridation-distillation combined method
was developed for renitridation process.
Actinides (An) recovered in a Cd phase byelectrolysis or reductive extraction, areconverted to nitride by heating the An-Cd alloys
in N2 gas stream. Technical feasibility had been
proved with small scale experiments using TRU
elements. Our recent studies contain thescale-up of the apparatus for this process and●: GdN2θ（deg.）Fig.2 XRD profile of the GdN product.

Contact (Group Leader):Hirokazu HAYASHI
hayashi.hirokazu55@jaea.go.jp25

FY2018 NSEC Publications

Publication list
（added in March 2020）

Nuclear Data and Reactor Engineering Division
Nuclear Data Center
Papers1) Measurements of neutron total and capture crosssections of 241Am with ANNRI at J-PARC, K.
Terada, A. Kimura, T. Nakao, S. Nakamura, K.
Mizuyama, N. Iwamoto, O. Iwamoto, H. Harada,
T. Katabuchi, M. Igashira, T. Sano, Y. Takahashi,
C.-H. Pyeon, S. Fukutani, T. Fujii, T. Yagi, K.
Takamiya & J. Hori, J. Nucl. Sci. Tech. 55(10),1198 (2018).
2) Role of breakup processes in deuteron-induced
spallation reactions at 100–200 MeV/nucleon, S.
Nakayama, N. Furutachi, O. Iwamoto & Y.
Watanabe, Phys. Rev. C 98(4), 044606 (2018).
3) Neutron energy dependence of delayed neutron
yields and its assessments, F. Minato, J. Nucl. Sci.
Tech. 55(9), 1054 (2018).
4) Theoretical calculation of neutron cross sections
for 90,91,92,94,96Zr in the incident energy range
between 200 keV and 20 MeV, A. Ichihara, J.
Nucl. Sci. Tech. 55(9), 1087 (2018).
5) Evaluation of neutron capture cross section on
205Pb with photonuclear data, N. Iwamoto & T.
Shizuma, EPJ Web of Conferences 178, 06004(2018).
6) Measurements of gamma-ray emission
probabilities in the decay of americium-244g, S.
Nakamura, K. Terada, A. Kimura, T. Nakao, O.
Iwamoto, H. Harada, A. Uehara, K. Takamiya &T. Fujii, J. Nucl. Sci. Tech. 56(1), 123 (2019).
7) Developing reliable reaction gamma-ray data, P.
Dimitriou, T. Belgya, Y.-S. Cho, D. Filipescu, R.
Firestone, S. Goriely, N. Iwamoto, T. Kawano, J.
Kopecky, M. Krticka, V. Plujko, S. Siem, R.
Schwengner, H. Utsunomiya, V. Vlarlamov, M.
Wiedeking & R. Xu, EPJ Web of Conferences
178, 06005 (2018).
8) Dipole strength distribution in 206Pb for theevaluation of the neutron capture cross section of
205Pb, T. Shizuma, N. Iwamoto, A. Makinaga, R.
Massarczyk, R. Schwengner, R. Beyer, D.
Bemmerer, M. Dietz, A. Junghans, T. Kögler, F.
Ludwig, S. Reinicke, S. Schulz, S. Urlaß & A.
Wagner, Phys. Rev. C 98(6), 064317 (2018).

9) Experimental validation of the brightness
distribution on the surfaces of coupled anddecoupled moderators composed of 99.8%
parahydrogen at the J-PARC pulsed spallation
neutron source, M. Harada, M. Teshigawara, M.
Ohi, E. Klinkby, L. Zanini, K. Batkov, K. Oikawa,Y. Toh, A. Kimura, Y. Ikeda, Nucl. Inst. &Methods in Phys. Res., A 903, 38 (2018).
10) 7Be(n,p)7Li Reaction and the Cosmological
Lithium Problem: Measurement of the Cross
Section in a Wide Energy Range at n_TOF at
CERN, L. Damone, et al. (The n_TOF
Collaboration (H. Harada & A. Kimura)), Phys.
Rev. Lett. 121(4), 042701 (2018).
11) Cutting-edge studies on Nuclear Data for
Continuous and Emerging Need (8); Evolution of
the nuclear data library JENDL, O. Iwamoto, K.
Shibata, N. Iwamoto & G. Chiba, J. the Atomic
Energy Soc. Jpn 60(6), 357 (2018) (in Japanese).
12) Measurement of 73Ge(n,γ) cross sections andimplications for stellar nucleosynthesis, C.
Lederer-Woods, et al. (The n_TOF Collaboration(H. Harada & A. Kimura)), Phys. Lett. B 790, 458(2019).
13) Cross section measurements of 155,157Gd(n,γ)
induced by thermal and epithermal neutrons, M.
Mastromarco, et al. (The n_TOF Collaboration(H. Harada & A. Kimura)), Eur. Phys. J. A 55, 9(2019).
14) Gamma-ray spectrum from thermal neutron
capture on gadolinium-157, K. Hagiwara, T.
Yano, T. Tanaka, M. Singh Reen, P. Kumar Das,
S. Lorenz, I. Ou, T. Sudo, Y. Yamada, T. Mori, T.
Kayano, R. Dhir, Y. Koshio, M. Sakuda, A.
Kimura, S. Nakamura, N. Iwamoto, H. Harada,
M. Wurm, W. Focillon, M. Gonin, A. Ali & G.
Collazuol, Prog. Theor. Exp. Phys. 2019, 023D01(2019).
15) ACE library of JENDL-4.0/HE, N. Matsuda, S.
Kunieda, T. Okamoto, K. Tada & C. Konno,
Progress in Nucl. Sci. & Tech. 6(Proc. ISORD-9),
225 (2019).

JAEA Reports
1) Present Status and Future Plan of JENDL, O.

Iwamoto, JAEA-Conf 2018-001 (Proc. the 201726

FY2018 NSEC Publications
spectrometry, Y. Shibahara, A. Uehara, T. Fujii, S.
Nakamura, A. Kimura, B. Hales & O. Iwamoto,
JAEA-Conf 2018-001 (Proc. the 2017
Symposium on Nuclear Data; November 16-17,
2017, iVil, Tokai-mura, Ibaraki, Japan), 205(2018).
4) Measurement of the Neutron Capture Cross
Section of 237Np using ANNRI at MLF/J-PARC,
G. Roviral, T. Katabuchi, K. Tosaka, A. Kimura& S. Nakamura, JAEA-Conf 2018-001 (Proc. the2017 Symposium on Nuclear Data; November
16-17, 2017, iVil, Tokai-mura, Ibaraki, Japan),
125 (2018).

Symposium on Nuclear Data; November 16-17,
2017, iVil, Tokai-mura, Ibaraki, Japan), 87(2018).
2) Progress of neutron-capture cross-section
measurements Promoted by ImPACT Project at
ANNRI in MLF of J-PARC, S. Nakamura, A.
Kimura, B. Yamada Hales, O. Iwamoto, Y.
Shibahara, A. Uehara & T. Fujii, JAEA-Conf
2018-001 (Proc. the 2017 Symposium on Nuclear
Data; November 16-17, 2017, iVil, Tokai-mura,
Ibaraki, Japan), 199 (2018).
3) Analysis of 135Cs/137Cs isotopic ratio for samples
used for neutron capture cross section
measurement project by thermal ionization mass

Research Group for Reactor Physics and Standard Nuclear Code System
PapersCharacteristics of Next-Generation Fast Reactors,
K. Takino, K. Sugino, K. Yokoyama, T. Jin & S.
Ohki, Proc. ICAPP 18, 1214 (2018).
8) Improvement of Probability Table Generation
using Ladder Method for a New Nuclear Data
Processing System FRENDY, K. Tada, Proc.
PHYSOR 2018, 2929 (2018).
9) 炉定数調整法と拡張バイアス因子法の理論
統合, K. Yokoyama, 炉物理の研究 70 (2018)(in Japanese).
10) Research and development roadmap for reactor
physics 2017 ~future of reactor physics projectedby next generations~, A. Yamamoto, G. Chiba, K.
Kirimura, Y. Miki & K. Yokoyama, J. the Atomic
Energy Soc. Jpn 60(4), 242 (2018) (in Japanese).
11) 第 30 回 NEA 核データ評価国際協力ワー
キ ン グ パ ー テ ィ （ WPEC ） 会 合 報 告 , O.
Iwamoto, N. Iwamoto, A. Kimura, K. Yokoyama,
K. Tada, 核データニュース 120, 35 (2018) (inJapanese).
12) IAEA Technical Meeting “Nuclear Data
Processing” に関する会合報告, K. Tada, 核データニュース 122, 9 (2019) (in Japanese).
13) 純 国 産 次 世 代 核 デ ー タ 処 理 コ ー ド
FRENDY の開発, K. Tada, 炉物理の研究 71(2019) (in Japanese).

1) AMPX MG library of JENDL-4.0, C. Konno,
Progress in Nucl. Sci. & Tech. 6(Proc. ISORD-9),
117 (2019).
2) Effect of IAEA patch for TRANSX2.15, C.
Konno, S. Kwon & G. Fischer, Proc. ANS
RPSD2018, 25264 (2018).
3) Generalized formulation of extended crosssection adjustment method based on minimum
variance unbiased linear estimation, K.
Yokoyama & T. Kitada, J. Nucl. Sci. Tech. 56(1),87 (2019).
4) Comparative Study on Prediction Accuracy
Improvement Methods with the Use of Integral
Experiments for Neutronic Characteristics ofFast Reactors, K. Yokoyama & T. Kitada, Proc.
ICAPP 18, 1221 (2018).
5) ACE library of JENDL-4.0/HE, N. Matsuda, S.
Kunieda, T. Okamoto, K. Tada & C. Konno,
Progress in Nucl. Sci. & Tech. 6(Proc. ISORD-9),
225 (2019).
6) Coupled Analysis of Fuel Debris Distribution andRecritiality by both Multiphase/Multicomponent
Flow and Continuous Energy Neutron Transport
Monte Carlo Simulations, S. Yamashita, K. Tada,
H. Yoshida & K. Suyama, Trans. the Atomic
Energy Soc. Jpn 17(3/4), 99 (2018) (in Japanese).
7) Investigation of the Core Neutronics Analysis
Conditions for Evaluation of Burn-up Nuclear

JAEA Reports
JAEA-Research 2018-011 (2019) (in Japanese).
3) Applicability of Statistical Geometry Model toLight Water Moderating Systems, T. Mori, K.
Kojima & K. Suyama, JAEA-Research 2018-010(2019) (in Japanese).

1) Nuclear data processing code FRENDY version
1, K. Tada, S. Kunieda & Y. Nagaya, JAEAData/Code 2018-014 (2019).
2) Development of the Unified Cross-section Set
ADJ2017, K. Yokoyama, K. Sugino, M. Ishikawa,
S. Maruyama, Y. Nagaya, K. Numata & T. Jin,

27

FY2018 NSEC Publications

Research Group for Nuclear Sensing
Papers1) Termination of Electron Acceleration in
ThundercloudbyIntracloud/IntercloudDischarge, Y. Wada, G.S. Bowers, T. Enoto, M.
Kamogawa, Y. Nakamura, T. Morimoto, D.M.
Smith, Y. Furuta, K. Nakazawa, T. Yuasa, A.
Matsuki, M. Kubo, T. Tamagawa, K. Makishima& H. Tsuchiya, Geophys. Res. Lett. 45(11), 5700
(2018).
2) Experimental validation of the brightness
distribution on the surfaces of coupled anddecoupled moderators composed of 99.8%
parahydrogen at the J-PARC pulsed spallation
neutron source, M. Harada, M. Teshigawara, M.
Ohi, E. Klinkby, L. Zanini, K. Batkov, K. Oikawa,Y. Toh, A. Kimura, Y. Ikeda, Nucl. Inst. &Methods in Phys. Res., A 903, 38 (2018).
3) Development of Active Neutron NDA System for

Nuclear Materials, Y. Toh, A. Ohzu, H. Tsuchiya,
K. Furutaka, F. Kitatani, M. Komeda, M. Maeda,
M. Koizumi, J. Heyse, C. Paradela, W.
Mondelaers, P. Schillebeeck, T. Bogucarska, K.
Abbas, B. Pederson, Proc. INMM-59 (2018).
4) Development of differential die-away techniquein an integrated active neutron NDA system fornuclear non-proliferation and nuclear security, A.
Ohzu, M. Maeda, M. Komeda, Y. Toh, M.
Koizumi & M. Seya, Conf. Record 2017 IEEE
NSS/MIC (2018).
5) Neutron Resonance Transmission Analysis for
Measurement of Nuclear Materials, H. Tsuchiya,
F. Kitatani, Y. Toh, C. Paradela, J. Heyse, S.
Kopecky & P. Schillebeeck, Proc. INMM-59(2018).

Fuels and Materials Engineering Division
Research Group for Corrosion Resistant Materials
PapersAnalysis 51(12), 1207 (2019).
6) Effect of re-oxidation rate of additive cations on
corrosion rate of stainless steel in boiling nitricacid solution, E. Irisawa, M. Yamamoto, C. Kato,
T. Motooka & Y. Ban, J. Nucl. Sci. Tech. 56(4),337 (2018).
7) Establishment and Amendment of Test Standards
for Evaluating Stress Corrosion Cracking
Initiation in High temperature Water, R. Ishibashi,
K. Fujimoto, C. Kato, Y. Miyahara, K. Kako, K.
Takeda, Y. Sakakibara & Y. Watanabe, Zairyo-toKankyo 67(11), 442 (2018) (in Japanese).
8) Mass transfer inside narrow crevice of SUS316L
in high temperature water, M. Yamamoto, Y.
Soma, T. Igarashi & F. Ueno, Proc. EUROCORR
2018, 103467 (2018).
9) Investigation of the effects of irradiation on
corrosive
environmentsusingin-situelectrochemical measurements during gammaray irradiation, T. Sato & F. Ueno, Proc.
EUROCORR 2018, 115387 (2018).
10) Effects of dissolved oxygen and ion irradiationon the corrosion of FeCrAl-ODS in hightemperature water simulating BWR operating
conditions, T. Sato, Proc. TOPFUEL 2018,
A0083 (2018).

1) Localized Corrosion in Crevice of SUS316
Stainless Steel in Oxygenated High Temperatureand High Purity Water, Y. Soma & F. Ueno,
Zairyo-to-Kankyo 67(5), 222 (2018) (inJapanese).
2) In-situ Measurement of Electrical Conductivityof Solution within Crevice of Stainless Steel inHigh Temperature and High Purity Water, Y.
Soma, A. Komatsu & F. Ueno, Zairyo-to-Kankyo
67(9), 381 (2018) (in Japanese).
3) Computational Analysis on Relation between
Iron Surface Condition and Surface Potential
Change, T. Igarashi, A. Komatsu, M. Yamaguchi,
K. Ebihara & F. Ueno, Proc. APCCC18 (18thAsian Pacific Corrosion Control Conference),
FA-022 (2018).
4) IV. Electrochemical Measurements in Various
Environments – Nuclear Power Plant I(Electrochemical Measurement in Nuclear Power
Plant) –, F. Ueno, Zairyo-to-Kankyo 68(1), 2(2019) (in Japanese).
5) Auger electron spectroscopic analysis ofcorrosion products formed on A3003 aluminumalloy in model fresh water with different Zn2+
concentration, K. Otani, Md. Saiful Islam, M.
Sakairi & A. Kaneko, Surface and Interface28

FY2018 NSEC Publications

Research Group for Radiation Materials Engineering
Papers1) First-principles calculations of interaction
between solutes and dislocations in tungsten, T.
Tsuru, T. Suzudo, Nucl. Mater. Ener. 16, 221(2018).
2) Positronium in room temperature ionic liquids, T.
Hirade, Positron Sciences 11, 33 (2018) (inJapanese).
3) Quantum Beats on Triplet-Positronium Reactionsin Water, T. Hirade, JPS Conf. Proc. 25, 011021(2019).
4) Reaction between Spin-correlated Triplet
Positronium and OH Radical in Water, T. Hirade,
JPS Conf. Proc. 25, 011022 (2019).
5) Fluoropolymer-based nanostructured membranes
created by swift-heavy-ion irradiation and theirenergy and environmental applications, T.
Yamaki, N. Nuryanthia,b, A. Kitamura, H.
Koshikawa, S. Sawada, K.-O. Voss, D. Severin &C. Trautmann, Nucl. Inst. & Methods in Phys.
Res., B 435, 162 (2018).
6)
Researchon
Nanostructure-Controlled
Functional Membranes Using High-Energy Ion
Beams: Fluoropolymer-Based Porous and IonExchange Membranes, T. Yamaki, A. Kitamura,
S. Sawada & H. Koshikawa, Bull. Soc. Sea Water
Sci. Jpn 72(2), 62 (2018) (in Japanese).
7) First-principles calculation of multiple hydrogensegregation along aluminum grain boundaries, M.
Yamaguchi, K.-I. Ebihara, M. Itakura, T. Tsuru,
K. Matsuda & H. Toda, Comp. Mater. Sci. 156,
368 (2019).
8) Interpretation of thermal desorption spectra ofhydrogen from aluminum using numericalsimulation, K. Ebihara, M. Yamaguchi, T. Tsuru& M. Itakura, J. Jpn Inst. Light Metals 68(11),596 (2018) (in Japanese).
9) Surface energy reduction by dissociativehydrogen adsorption on inner surface of pore inaluminum, M. Yamaguchi, T. Tsuru, K. Ebihara& M. Itakura, J. Jpn Inst. Light Metals 68(11),588 (2018) (in Japanese).
10) Microstructure evolution in a hydrogen charged
and aged Al–Zn–Mg alloy, A. Bendo, K. Matsuda,
S.-w. Lee, K. Nishimura, H. Toda, K. Shimizu, T.
Tsuru & M. Yamaguchi, Materialia 3, 50 (2018).
11) First-principles study of solvent-solute mixed
dumbbells in body-centered-cubic tungsten
crystals, T. Suzudo, T. Tsuru & A. Hasegawa, J.
Nucl. Mater. 505, 15 (2018).
12) Evaluation of the effect of spent fuel layout on
SFP cooling with MAAP5.04, S. Nishimura, M.

Satake, Y. Nishi, Y. Kaji & Y. Nemoto, Proc.11th
Korea-Japan Symposium on Nuclear Thermal
Hydraulics and Safety (NTHAS-11), N11P0172(2018).
13) Vaporlike phase of amorphous SiO2 is not aprerequisite for the core/shell ion tracks or ion
shaping, H. Amekura, P. Kluth, P. Mota-Santiago,
I. Sahlberg, V. Jantunen, A.A. Leino, H. Vazquez,
K. Nordlund, F. Djurabekova, N. Okubo & N.
Ishikawa, Phys. Rev. Mater. 2(9), 096001 (2018).
14) Effect of elastic collisions and electronic
excitation on lattice structure of NiTi bulk
intermetallic compound irradiated with energetic
ions, M. Ochi, H. Kojima, F. Hori, Y. Kaneno, S.
Semboshi, Y. Saitoh, Y. Okamoto, N. Ishikawa &A. Iwase, Nucl. Inst. & Methods in Phys. Res., B
427, 14 (2018).
15) Ag nanoparticles embedded in Nd:YAG crystals
irradiated with tilted beam of 200 MeV Xe ions:
optical dichroism correlated to particle reshaping,
R. Li, C. Pang, H. Amekura, F. Ren, R. Hübner,
S.-q. Zhou, N. Ishikawa, N. Okubo & F. Chen,
Nanotechnology 29(42), 424001 (2018).
16) Swift heavy ion irradiation to ZnO
nanoparticles: Steep degradation at low fluences
and stable tolerance at high fluences, H. Amekura,N. Okubo, F. Ren & N. Ishikawa, J. Applied Phys.
124(14), 145901 (2018).
17) Structure analysis of the defects generated by athermal spike in single crystal CeO2: A molecular
dynamics study, Y. Sasajima, N. Ajima, R.
Kaminaga, N. Ishikawa & A. Iwase, Nucl. Inst. &Methods in Phys. Res., B 440, 118 (2019).
18) Structure of nitride layer formed on titanium
alloy surface by N2-gas exposure at hightemperatures, Y. Takeda, K. Iida, S. Sato, T.
Matsuo, Y. Nagashima, N. Okubo, K. Kondo & T.
Hirade, JPS Conf. Proc. 25, 011023 (2019).
19) Effect of long term thermal aging on the SCC
initiation susceptibility of L-grade austenitic
stainless steel, K. Kondo, T. Hirade, S. Aoki, S.
Yamashita & Y. Kaji, Proc. FONTEVRAUD 9(International Symposium on Contribution ofMaterials Investigations and Operating
Experience to Light Water NPPs’ Safety,
Performance and Reliability), 000154 (2018).
20) Study on oxidation model for Zircalloy-2
cladding in SFP accident condition, Y. Kaji, Y.
Nemoto, T. Onizawa, T. Kanazawa, K.
Nakashima & M. Tojo, Proc. EUROCORR 2018,
113517 (2018).

29

FY2018 NSEC Publications

Research Group for High Temperature Science on Fuel Materials
Papers1) Lattice expansion in ZrN and Dy0.3Zr0.7N
irradiated by 200 MeV Xe ions, S. Takaki, M.
Takano & N. Ishikawa, Progress in Nucl. Sci. &Tech. 5(Proc. Actinides 2017), 204 (2018).

2) Chemical state analysis of simulated corium
debris by EXAFS, Y. Okamoto & M. Takano,
Progress in Nucl. Sci. & Tech. 5(Proc. Actinides2017), 200 (2018).

1) 6.2 R&D for minor actinides transmutation, M.
Takano, 我が国将来世代のエネルギーを担ー 安 全 保 障 ～ (NSA/commentaries, No.24),

Book

163 (2019) (in Japanese).

う核燃料サイクル～脱炭素社会のエネルギ

Nuclear Chemistry Division
Research Group for Radiochemistry
Papers1) Mutual separation of trivalent lanthanide andactinides by hydrophilic and lipophilic
multidentate diamides, Y. Sasaki & K. Morita,
Progress in Nucl. Sci. & Tech. 5(Proc. Actinides2017), 27 (2018).
2) Mechanism of phase transfer of uranyl ions: avibrationalsumfrequency
generation
spectroscopy study on solvent extraction in
nuclear reprocessing, R. Kusaka & M. Watanabe,
Phys. Chem. Chem. Phys. 20(47), 29588 (2018).
3) A Spectroscopic technique for analysis developedin the field of nuclear energy, R. Kusaka, J. theSpectroscopical Soc. Jpn 67(6), 239 (2018) (inJapanese).
4) Theoretical Elucidation of Am(III)/Cm(III)
Separation Mechanism with Diamide-type
Ligands Using Relativistic Density Functional
Theory Calculation, M. Kaneko, H. Suzuki & T.
Matsumura, Inorg. Chem. 57(23), 14513 (2018).

5) The role of surface-bound hydroxyl radicals in
the reaction between H2O2 and UO2, A.B. Fidalgo,
Y. Kumagai & M. Jonsson, J. Coord. Chem.
71(11-13), 1799 (2018).
6) Variation of half-life and internal-conversion
electron energy spectrum between 235mU oxideand fluoride, Y. Shigekawa, Y. Kasamatsu, Y.
Yasuda, M. Kaneko, M. Watanabe & A.
Shinohara, Phys. Rev. C 98(1), 014306 (2018).
7) On/off spin-crossover phenomenon and controlof the transition temperature in assembled
Iron(II) complexes, S. Nakashima, M. Kaneko, K.
Yoshinami, S. Iwai & H. Dote, Hyperfine Interact.
239(1), 39 (2018).
8) Computational chemical analysis of Eu(III) andAm(III) complexes with pnictogen-donor ligands
using DFT calculations, T. Kimura, M. Kaneko,
M. Watanabe, S. Miyashita & S. Nakashima,
Dalton Trans. 47(42), 14924 (2018).

Research Group for Analytical Chemistry
PapersK.-i. Ishimori, Y. Kameo & S. Saito, Anal. Chim.
Acta 1032, 188 (2018).
3) In Situ Time-Resolved XAFS Studies on LaserInduced Particle Formation of Palladium Metal in
an Aqueous/EtOH Solution, M. Saeki, D.
Matsumura, T. Yomogida, T. Taguchi, T. Tsuji, H.
Saitoh & H. Ohba, J. Phys. Chem. C 123(1), 817(2018).
4) Electrochemistry of actinide, Y. Kitatsuji,
RADIOISOTOPES 67(10), 483 (2018) (inJapanese).
5) Development of separation technique for1) Determination of 107Pd in Pd purified by selective
precipitation from spent nuclear fuel by laser
ablation ICP-MS, S. Asai, M. Ohata, T.
Yomogida, M. Saeki, H. Ohba, Y. Hanzawa, T.
Horita & Y. Kitatsuji, Anal. Bioanal. Chem.
411(5), 973 (2019).
2) Safe and rapid development of capillaryelectrophoresis for ultratrace uranyl ions inradioactive samples by way of fluorescent probe
selection for actinide ions from a chemical library,
T. Haraga, K. Ouchi, Y. Sato, H. Hoshino, R.
Tanaka, T. Fujihara, H. Kurokawa, M. Shibukawa,30

FY2018 NSEC Publications
platinum-group metals from radioactive liquid
waste utilizing laser-induced particulate

formation, M. Saeki, S. Asai & H. Ohba, Bunseki
2018(4), 138 (2018) (in Japanese).

Environment and Radiation Sciences Division
Research Group for Environmental Science
Papers(2018).
10) Fukushima 137Cs releases dispersion modellingover the Pacific Ocean. Comparisons of models
with water, sediment and biota data, R. Periáñeza,R. Bezhenar, I. Brovchenko, K.T. Jung, Y.
Kamidara, K.O. Kim, T. Kobayashi, L. Liptak, V.
Maderich, B.I. Min & K.S. Su, J. Environmental
Radioactivity 198, 50 (2019).
11) Atmospheric Modeling of 137Cs Plumes From
the Fukushima Daiichi Nuclear Power Plant—
Evaluation of the Model Intercomparison Data of
the Science Council of Japan, K. Kitayama, Y.
Morino, M. Takigawa, T. Nakajima, H. Hayami,
H. Nagai, H. Terada, K. Saito, T. Shimbori, M.
Kajino, T.T. Sekiyama, D. Didier, A. Mathieu, D.
Quélo, T. Ohara, H. Tsuruta, Y. Oura, M. Ebihara,
Y. Moriguchi & T. Shibata, J. Geophys. Res.:
Atmospheres 123(14), 7754 (2018).
12) Spectral reflectance and associated photographof boreal forest understory formation in interior
Alaska, H. Kobayashi, R. Suzuki, W. Yang, H.
Ikawa, T. Inoue, H. Nagano & Y. Kim, Polar
Data J. 2, 14 (2018).
13) Links between annual surface temperature
variation and land cover heterogeneity for aboreal forest as characterized by continuous,
fibre-optic DTS monitoring, K. Saito, G. Iwahana,
H. Ikawa, H. Nagano & R.C. Busey, Geosci.
Instrum. Method. Data Syst. 7(3), 223 (2018).
14) Model Intercomparison of Atmospheric 137Cs
From the Fukushima Daiichi Nuclear Power
Plant Accident: Simulations Based on Identical
Input Data, Y. Sato, M. Takigawa, T.T. Sekiyama,
M. Kajino,H. Terada, H. Nagai, H. Kondo, J.
Uchida, D. Goto,D. Quélo, A. Mathieu, A. Quérel,S. Fang, Y. Morino, P. von Schoenberg, H. Grahn,
N. Brännström, S. Hirao, H. Tsuruta, H.
Yamazawa & T. Nakajima, J. Geophys. Res.:
Atmospheres 123(20), 11748 (2018).
15) In Situ Observations Reveal How Spectral
Reflectance Responds to Growing Season
Phenology of an Open Evergreen Forest in
Alaska, H. Kobayashi, S. Nagai, Y. Kim, W. Yang,
K. Ikeda, H. Ikawa, H. Nagano & R. Suzuki,
Remote Sensing 10(7), 1071 (2018).

1) Submesoscale Mixing on Initial Dilution ofRadionuclides Released From the Fukushima
Daiichi Nuclear Power Plant, Y. Kamidaira, Y.
Uchiyama, H. Kawamura, T. Kobayashi & A.
Furuno, J. Geophys. Res.: Oceans 123(4), 2808
(2018).
2) Impacts of anthropogenic source from thenuclear fuel reprocessing plants on global
atmospheric iodine-129 cycle: A model analysis,
M. Kadowaki, G. Katata, H. Terada, T. Suzuki, H.
Hasegawa, N. Akata & H. Kakiuchi, Atmospheric
Environment 184, 278 (2018).
3) Radiocesium distribution in aggregate-size
fractions of cropland and forest soils affected by
the Fukushima nuclear accident, J. Koarashi, S.
Nishimura, M. Atarashi-Andoh, T. Matsunaga, T.
Sato & S. Nagao, Chemosphere 205, 147 (2018).
4) Vertical distribution of 129I released from the
Fukushima Daiichi Nuclear Power Plant in the
Kuroshio and Oyashio current areas, T. Suzuki, S.
Otosaka, J. Kuwabara, H. Kawamura & T.
Kobayashi, Marine Chem. 204, 163 (2018).
5) Distribution and fate of 129I in the seabedsediment off Fukushima, S. Otosaka, Y. Satoh, T.
Suzuki, J. Kuwabara & T. Nakanishi, J.
Environmental Radioactivity 192, 208 (2018).
6) Importance of root uptake of 14CO2 on 14C
transfer to plants impacted by below-ground
14CH
4 release, M. Ota & T. Tanaka, J.
Environmental Radioactivity 201, 5 (2019).
7) Low 137Cs retention capability of organic layers
in Japanese forest ecosystems affected by the
Fukushima nuclear accident, J. Koarashi & M.
Atarashi‑Andoh, J. Radioanal. Nucl. Chem.
320(1), 179 (2019).
8) Factors controlling 134Cs activity concentrations
in sediment collected off the coast of Fukushima
Prefecture in 2013–2015, M. Fukuda, T. Aono, S.
Yamazaki, T. Ishimaru, J. Kanda, J. Nishikawa &S. Otosaka, Geochemical J. 52(2), 201 (2018).
9) Analysis of the Ozone Reduction Event Over theSouthern Tip of South America in November
2009, H. Akiyoshi, M. Kadowaki, H. Nakamura,T. Sugita, T. Hirooka, Y. Harada & A. Mizuno, J.
Geophys. Res.: Atmospheres 123(22), 12523

31

FY2018 NSEC Publications16) A Biological network around Okinawa Island
analyzed with a coupled high-resolution ocean
circulation and lagrangian particle tracking
model, Y. Uchiyama, T. Miyagawa, S. Odani & Y.
Kamidaira, J. Jpn Soc. Civil Eng., Ser. B2(Coastal Eng.) 74(2), I_1291 (2018).

17) Influences of the Kuroshio on Interisland
Remote Connectivity of Corals Across the Nansei
Archipelago in the East China Sea, Y. Uchiyama,
S. Odani, M. Kashima, Y. Kamidaira & Satoshi
Mitarai, J. Geophys. Res.: Oceans 123(12), 9245
(2018).

JAEA Report1) Submesoscale Eddy Mixing in Coastal and Shelf
Seas (Thesis), Y. Kamidaira, JAEA-Review 2018-

021 (2018) (in Japanese).

Research Group for Radiation Transport Analysis
Papers1) Depth Distributions of RBE-weighted Dose andPhoton-isoeffective Dose for Boron Neutron
Capture Therapy, T. Sato, S. Masunaga, H.
Kumada & N. Hamada, Radiation Protection
Dosimetry 183(1-2), 247 (2019).
2) Real Time and Automatic Analysis Program for
WASAVIES: Warning System for Aviation
Exposure to Solar Energetic Particles, T. Sato, R.
Kataoka, D. Shiota, Y. Kubo, M. Ishii, H. Yasuda,
S. Miyake, I.-C. Park & Y. Miyoshi, Space
Weather 16(7), 924 (2018).
3) Measurement of displacement cross sections ofaluminum and copper at 5 K by using 200 MeV
protons, Y. Iwamoto, M. Yoshida, T. Yoshiie, D.
Satoh, H. Yashima, H. Matsuda, S. Meigo & T.
Shima, J. Nucl. Mater. 508, 195 (2018).
4) Nowcast and forecast of galactic cosmic ray(GCR) and solar energetic particle (SEP) fluxes
in magnetosphere and ionosphere – Extension of
WASAVIES to Earth orbit, T. Sato, R. Kataoka,
D. Shiota, Y. Kubo, M. Ishii, H. Yasuda, S.
Miyake, Y. Miyoshi, H. Ueno & A. Nagamatsu, J.
Space Weather Space Climate 9, A9 (2019).
5) Measurement of neutron-production doubledifferential cross sections of natC, 27Al, natFe, andnatPb by 20, 34, 48, 63, and 78 MeV protons in the
most-forward direction, D. Satoh, Y. Iwamoto &T. Ogawa, Nucl. Inst. & Methods in Phys. Res., A
920, 22 (2019).
6) Three-dimensional analysis using polygons in
Particle and Heavy Ion Transport code System(PHITS), T. Furuta, Proc.ANS RPSD2018, 25504(2018).
7) Estimation method of systematic uncertainties inMonte Carlo particle transport simulation basedon analysis of variance, S. Hashimoto & T. Sato,
J. Nucl. Sci. Tech. 56(4), 345 (2019).
8) Development of a stochastic biokinetic method
and its application to internal dose estimation for
insoluble cesium-bearing particles, K. Manabe &M. Matsumoto, J. Nucl. Sci. Tech. 56(1), 78(2019).

9)Integrated Simulation of Fragmentation,
Evaporation, and Gamma-decay Processes in theInteraction of Cosmic-ray Heavy Ions with the
Atmosphere using PHITS, T. Ogawa, S.
Hashimoto, T. Sato, K. Niita & T. Kamae, Proc.
ICPPA 2017, 391 (2018).
10) Cluster formation in relativistic nucleus-nucleus
collisions, T. Ogawa, T. Sato, S. Hashimoto & K.
Niita, Phys. Rev. C 98(2), 024611 (2018).
11) Analysis of scintillation light intensity by
microscopic radiation transport calculation and
Förster quenching model, T. Ogawa, T. Yamaki &T. Sato, PLoS ONE 13(8), e0202011 (2018).
12) Establishment of a Novel Detection System for
Measuring Primary Knock-on Atoms, P.-E.Tsai,Y. Iwamoto, M. Hagiwara, T. Sato, T. Ogawa, D.
Satoh, S.-I. Abe, M. Ito & H. Watabe, Conf.
Record 2017 IEEE NSS/MIC (2018).
13) Internal doses from radionuclides and theirhealth effects following the Fukushima accident,
T. Ishikawa, M. Matsumoto, T. Sato, I.
Yamaguchi & M. Kai, J. Radiol. Prot. 38(4),1253 (2018).
14) Radiation Dose Nowcast for the Ground Level
Enhancement on 10–11 September 2017, R.
Kataoka, T. Sato, S. Miyake, D. Shiota & Y. Kubo,
Space Weather 16(7), 917 (2018).
15) A New Standard DNA Damage (SDD) Data
Format, J. Schuemann, A.L. McNamara, J.W.
Warmenhoven, N.T. Henthorn, K.J. Kirkby, M.J.
Merchant, S. Ingram, H. Paganetti, K.D. Held, J.
Ramos-Mendez, B. Faddegon, J. Perl, D.T.
Goodhead, I. Plante, H. Rabus, H. Nettelbeck, W.
Friedland, P. Kundrát, A. Ottolenghi, G. Baiocco,
S. Barbieri, M. Dingfelder, S. Incerti, C.
Villagrasa, M. Bueno, M.A. Bernal, S. Guatelli,
D. Sakata, J.M.C. Brown, Z. Francis, I. Kyriakou,
N. Lampe, F. Ballarini, M.P. Carante, M.
Davídková, V. Štěpán, X. Jia, F.A. Cucinotta, R.
Schulte, R.D. Stewart, D.J. Carlson, S. Galer, Z.
Kuncic, S. Lacombe, J. Milligan, S.H. Cho, G.
Sawakuchi, T. Inaniwa, T. Sato, W. Li, A.V.

32

FY2018 NSEC Publications
Event Upsets in 65-nm UTBB SOI SRAMs, S.
Manabe, Y. Watanabe, W. Liao, M. Hashimoto, K.
Nakano, H. Sato, T. Kin, S.-I. Abe, K. Hamada,
M. Tampo & Y. Miyake, IEEE Transactions on
Nucl. Sci. 65(8), 1742 (2018).
22) Estimation of the therapeutic effect of BNCT
based on the dose distributions in cellular scale,
T. Sato, Isotope News 760, 2 (2018) (in Japanese).
23) Radiation Damage Calculation in PHITS andBenchmarking Experiment for Cryogenicsample High-energy Proton Irradiation, Y.
Iwamoto, H. Matsuda, S. Meigo, D. Satoh, T.
Nakamoto, M. Yoshida, Y. Ishi, Y. Kuriyama, T.
Uesugi, H. Yashima, T. Yoshiie, T. Shima & R. M.
Ronningen, Proc. HB2018, 116 (2018).
24) Cutting-edge studies on nuclear data forcontinuous and emerging need, 7; Challenge tohigh energy area, N. Shigyo, H. Iwase, Y.
Iwamoto & T. sato, J. the Atomic Energy Soc. Jpn60(5), 294 (2018) (in Japanese).
25) Review of the performance of a car-borne
survey system, KURAMA-II, used to measure
the dose rate after the Fukushima Dai-ichi
Nuclear Power Plant accident, S. Tsuda, M.
Tanigaki, T. Yoshida & K. Saito, 放 射 線
Ionizing radiation 44(3), 109 (2018).
26) 2018 Annual Meeting of AESJ, Joint Session of
Nuclear Data Subcommittee and Sigma Special
Advisory Committee; Present status and future of
nuclear data evaluation code in Japan, 4; Role andimprovement of nuclear reaction models in the
PHITS code, S. Hashimoto, T. Sato, Y. Iwamoto,T. Ogawa, T. Furuta, S.-I. Abe & K. Niita, 核データニュース 120, 26 (2018) (in Japanese).

Solov'yov, E. Surdutovich, M. Durante, K.M.
Prise & S.J. McMahon, Radiation Res. 191(1), 76(2019).
16) Dosimetric Impact of a New Computational
Voxel Phantom Series for the Japanese Atomic
Bomb Survivors: Children and Adults, K. Griffin,
C. Paulbeck, W. Bolch, H. Cullings, S. Egbert, S.
Funamoto, T. Sato, A. Endo, N. Hertel & C. Lee,
Radiation Res. 191(4), 369 (2019).
17) A scalable and deformable stylized model of theadult human eye for radiation dose assessment, D.
El Basha, T. Furuta, S. S R Iyer & W.E Bolch,
Phys. Med. Biol. 63(10), 105017 (2018).
18) Transient ionization of the mesosphere duringauroral breakup: Arase satellite and ground-based
conjugate observations at Syowa Station, R.
Kataoka, T. Nishiyama, Y. Tanaka, A. Kadokura,
H.A. Uchida, Y. Ebihara, M.K. Ejiri, Y.
Tomikawa, M. Tsutsumi, K. Sato, Y. Miyoshi, K.
Shiokawa, S. Kurita, Y. Kasahara, M. Ozaki, K.
Hosokawa, S. Matsuda, I. Shinohara, T.
Takashima, T. Sato, T. Mitani, T. Hori & N.
Higashio, Earth, Planets & Space 71, 9 (2018).
19) Multi-threading performance of Geant4,
MCNP6, and PHITS Monte Carlo codes fortetrahedral-mesh geometry, M.C. Han, Y.S. Yeom,
H.S. Lee, B. Shin, CH. Kim & T. Furuta, Phys.
Med. Biol. 63(9), 09NT02 (2018).
20) Measurement and Mechanism Investigation of
Negative and Positive Muon-Induced Upsets in
65-nm Bulk SRAMs, W. Liao, M. Hashimoto, S.
Manabe, Y. Watanabe, S.-I. Abe, K. Nakano, H.
Sato, T. Kin, K. Hamada, M. Tampo & Y. Miyake,
IEEE Transactions on Nucl. Sci. 65(8), 1734(2018).
21) Negative and Positive Muon-Induced Single

LWR Key Technology Development Division
Development Group for Thermal-Hydraulics Technology
PapersPlate of Fuel Bundle to Evaluate Spray Cooling
Capability in Spent Fuel Pool, T. Nagatake, Y.
Koizumi, M. Shibata, H. Yoshida, Y. Nemoto &Y. Kaji, Proc. ICAPP 18, 414 (2018).
4) Development of Numerical Simulation Method
to Evaluate Molten Material Behaviors in
Nuclear Reactors: Estimation of Fuel Debris
Distribution in the Pedestal, S. Yamashita & H.
Yoshida, Proc. ICONE26, 82088 (2018).
5) Numerical Study on Effect of Pressure on
Behavior of Bubble Coalescence by Using
CMFD Simulation, A. Ono, T. Suzuki & H.

1) Validation of free-convective heat transfer
analysis with JUPITER to evaluate air-cooling
performance of fuel debris in dry method, S.
Uesawa, S. Yamashita, M. Shibata & H. Yoshida,
Mechanical Eng. J. 5(4), 18-00115 (2018).
2) Coupled Analysis of Fuel Debris Distribution andRecritiality by both Multiphase/Multicomponent
Flow and Continuous Energy Neutron Transport
Monte Carlo Simulations, S. Yamashita, K. Tada,
H. Yoshida & K. Suyama, Trans. the Atomic
Energy Soc. Jpn 17(3/4), 99 (2018) (in Japanese).
3) Study of CCFL Two-Phase Flow at Upper Tie

33

FY2018 NSEC Publications
Yoshida, Proc. ICONE26, 82564 (2018).
6) Development of Numerical simulation for Jet
Breakup Behavior in Complicated Structure of
BWR Lower Plenum (9) Evaluation of Effects ofFluids Properties on Jet Shape and Diameter ofFragments, T. Suzuki, H. Yoshida & Y. Abe, Proc.
ICONE26, 82580 (2018).
7) Numerical study on effect of nucleation site
density on behavior of bubble coalescence byusing CMFD simulation code TPFIT, A. Ono, T.
Suzuki & H. Yoshida, Proc. 12th International
Topical Meeting on Nuclear Reactor ThermalHydraulics, Operation and Safety (NUTHOS-12),
No.354 (2018).
8) Free convective heat transfer experiment tovalidate air-cooling performance analysis of fueldebris, S. Uesawa, S. Yamashita, M. Shibata & H.
Yoshida, Proc. 11th Korea-Japan Symposium on
Nuclear Thermal Hydraulics and Safety(NTHAS-11), N11P0027 (2018).
9) Development of numerical simulation method forsmall particles behavior in two-phase flow by
combining interface and Lagrangian particle
tracking methods, H. Yoshida, S. Uesawa, N.
Horiguchi, N. Miyahara & Y. Ose, Proc. 11th
Korea-Japan Symposium on Nuclear Thermal
Hydraulics and Safety (NTHAS-11), N11P0064(2018).
10) Numerical simulation of thermal hydraulics
around a beam window in accelerator-driven
system, S. Yamashita & H. Yoshida, Proc. 11th
Korea-Japan Symposium on Nuclear Thermal
Hydraulics and Safety (NTHAS-11), N11P0015(2018).
11) Penetration Behavior of Liquid Jet Falling Intoa Shallow Pool, F. Kimura, H. Yoshida, A.
Kaneko & Y. Abe, Proc. ICONE26, 81993 (2018).
12) Development of Numerical Simulation Method
to Evaluate Molten Material Behaviors in
Nuclear Reactors: Preliminary numericalsimulation for molten core relocation behavior in
BWR and PWR cores, Y. Ose, S. Yamashita & H.
Yoshida, Proc. ICONE26, 82565 (2018).

13) Liquid Film Flow on Vertical and Successive
Inclined Plate Modeling Flow Channel of Molten
Control Rod in Severe Accident, Y. Hihara, H.
Monji, Y. Abe, H. Yoshida & S. Yamashita, Proc.
ICONE26, 81690 (2018).
14) Evaluation of electronic state of Cs-adsorbed
clay minerals by NEXAFS analysis using DFT
calculations, C. Suzuki, T. Yaita, S. Suzuki, J.
Pacold, A.B. Altman, S.G. Minasian, T.
Tyliszczak, D.K. Shuh, H. Yoshida & M. Osaka,
J. Phys. Chem. Solids 127, 169 (2019).
15) Observation of dry patch behavior on copper
heat transfer surface and measurement of surface
temperature distribution in nucleate pool boiling,
S. Uesawa, A. Ono, Y. Koizumi, M. Shibata & H.
Yoshida, Proc. 55th National Heat Transfer
Symposium, G135 (2018) (in Japanese).
16) Development of Numerical Simulation Method
for Capturing Behavior of Aerosol Particles on
Gas-liquid Interface based on Interface Tracking
Method, H. Yoshida, S. Uesawa, N. Horiguchi, N.
Miyahara & Y. Ose, Proc. 23rd National
Symposium on Power & Energy Systems, B233
(2018) (in Japanese).
17) Observation of Capturing Behavior of Aerosol
Particles on Gas-liquid Interface, S. Uesawa, N.
Horiguchi, N. Miyahara & H. Yoshida, Proc. 23rd
National Symposium on Power & Energy
Systems, B234 (2018) (in Japanese).
18) Development of simultaneous evaluation
method of bubble behavior and electric field
distribution around WMS by using TPFIT and
EMSolution, S. Uesawa, T. Suzuki & H. Yoshida,
Proc. National 2018 Symposium on Multiphase
Flow, 0119 (2018) (in Japanese).
19) Simultaneous Measurement of Dry Patch
Behavior and Surface Temperature Distribution
for Copper Heat Transfer Surface with
Deposition Layer in Nucleate Pool Boiling, S.
Uesawa, A. Ono, Y. Koizumi, M. Shibata & H.
Yoshida, Proc. the Thermal Engineering
Conference 2018, A133/0111 (2018) (inJapanese).

Development Group for LWR Advanced Technology
Papers1) Chemical reaction kinetics dataset of Cs-I-B-MoO-H system for evaluation of fission productchemistry under LWR severe accident conditions,N. Miyahara, S. Miwa, N. Horiguchi, I. Sato &M. Osaka, J. Nucl. Sci. Tech. 56(2), 228 (2019).
2) Visualized measurement of extremely high-speed
droplets in Venturi scrubber, N. Horiguchi, H.
Yoshida & Y. Abe, J. Nucl. Sci. Tech. 56(3), 278(2019).
3) Effect of atmosphere on the vaporization

behavior of CsFeSiO₄, E. Suzuki, K. Nakajima &M. Osaka, Progress in Nucl. Sci. & Tech. 5(Proc.
Actinides 2017), 165 (2018).
4) An experimental investigation for atmosphericeffects on Cs chemisorption onto stainless steel,K Nakajima, E. Suzuki, N. Miyahara & M. Osaka,
Progress in Nucl. Sci. & Tech. 5(Proc. Actinides2017), 168 (2018).
5) Evaluation of electronic state of Cs-adsorbed
clay minerals by NEXAFS analysis using DFT34

FY2018 NSEC Publications
calculations, C. Suzuki, T. Yaita, S. Suzuki, J.
Pacold, A.B. Altman, S.G. Minasian, T.
Tyliszczak, D.K. Shuh, H. Yoshida & M. Osaka,
J. Phys. Chem. Solids 127, 169 (2019).
6) Modelling of Cesium Chemisorption under
Nuclear Power Plant Severe Accident Conditions,F. Miradji, C. Suzuki, S. Nishioka, E. Suzuki. K.
Nakajima & M. Osaka, Proc. 9th European

Review Meeting on Severe Accident Research(ERMSAR2019), 047 (2019).
7) Synthesis and Characterization of CeO2-Based
Simulated Fuel Containing CsI, Y. Takamatsu, H.
Ishii, Y.Ohishi, H. Muta, S. Yamanaka, E. Suzuki,
K. Nakajima, S. Miwa, M. Osaka & K. Kurosaki,
Trans. the Atomic Energy Soc. Jpn 17(3/4), 106(2018) (in Japanese).

Partitioning and Transmutation Technology Division
Research Group for Partitioning
Papers1) Uranium-based TRU multi-recycling withthermal neutron HTGR to reduce environmental
burden and threat of nuclear proliferation, Y.
Fukaya, M. Goto, H. Ohashi, X. Yan, T. Nishihara,
Y. Tsubata & T. Matsumura, J. Nucl. Sci. Tech.
55(11), 1275 (2018).
2) Theoretical Elucidation of Am(III)/Cm(III)
Separation Mechanism with Diamide-type
Ligands Using Relativistic Density Functional
Theory Calculation, M. Kaneko, H. Suzuki & T.
Matsumura, Inorg. Chem. 57(23), 14513 (2018).
3) Mechanism of Palladium(II) Adsorption from

Nitric Acid Solutions by a StyreneDivinylbenzene Copolymer Functionalized with
N,N,N-Trimethylglycine, T. Suzuki, H. Narita, T.
Ogata, H. Suzuki, T. Matsumura, T. Kobayashi,
H. Shiwaku & T. Yaita, Solvent Extr. Res.
Develop., Jpn 26(1), 11 (2019).
4) Mutual separation of trivalent lanthanide andactinides by hydrophilic and lipophilic
multidentate diamides, Y. Sasaki & K. Morita,
Progress in Nucl. Sci. & Tech. 5(Proc. Actinides2017), 27 (2018).

JAEA report
1) Comparison of Potential Radiotoxicity ofActinide Elements – Data for Consideration of
Optimum Recovery of Actinide Elements –, Y.

Morita, K. Nishihara & Y. Tsubata, JAEAData/Code 2018-017 (2019) (in Japanese).

Research Group for Nuclear Transmutation System Technology
Papers1) Investigations of accelerator reliability and decay
heat removal for accelerator-driven system, T.
Sugawara, H. Takei & K. Tsujimoto, Annals Nucl.
Energy 125, 242 (2019).
2) Estimation of sensitivity coefficient based onlasso-type penalized linear regression, R. Katano,
T. Endo, A. Yamamoto & K. Tsujimoto, J. Nucl.
Sci. Tech. 55(10), 1099 (2018).
3) Estimation Method of Prompt Neutron Decay
Constant Reducing Higher Order Mode Effect byLinear Combination, R. Katano, Nucl. Sci. Eng.
193(4), 431 (2019).
4) Count-loss effect in determination of prompt
neutron decay constant by neutron correlation
methods that employ two sets of neutron
counting systems, Y. Kitamura & M. Fukushima,
Annals Nucl. Energy 125, 328 (2019).
5) Experimental analyses of bismuth sample

reactivity worth at Kyoto University Critical
Assembly, C.H. Pyeon, M. Yamanaka, A. Oizumi,
M. Fukushima & K. Tsujimoto, J. Nucl. Sci. Tech.
55(11), 1324 (2018).
6) Design Study of Beam Window for AcceleratorDriven System With Subcriticality Adjustment
Rod, T. Sugawara, Y. Eguchi, H. Obayashi, H.
Iwamoto, H. Matsuda & K. Tsujimoto, Proc.
ICONE26, 81233 (2018).
7) Evaluation of Heat Removal During the Failureof the Core Cooling for New Critical Assembly,
Y. Eguchi, T. Sugawara, K. Nishihara, K.
Tsujimoto & Y. Tazawa, Proc. ICONE26, 82012(2018).
8) PR9-3 Measurement of MA Reaction Rates
Using Spallation Neutron Source, A. Oizumi, M.
Fukushima, K. Tsujimoto, M. Yamanaka, T. sano
& C.H. Pyeon, KURRI Progress Report 2017, 50

35

FY2018 NSEC Publications(2018).

JAEA Reports
1)

Measurement experiment of oxygen
concentration in liquid lead-bismuth eutectic;
Basic Tests and estimation of gamma-ray
irradiation effect, T. Sugawara, S. Kita, H.
Yoshimoto & N. Okubo, JAEA-Technology 2018008 (2018) (in Japanese).

2) Comparison of Potential Radiotoxicity ofActinide Elements – Data for Consideration of
Optimum Recovery of Actinide Elements –, Y.
Morita, K. Nishihara & Y. Tsubata, JAEAData/Code 2018-017 (2019) (in Japanese).

Research Group for MA Transmutation Fuel Cycle
Paper1) Dissolution and chemical analysis of Zr-basedlanthanide nitrides, H. Hayashi & R. Chiba,

Progress in Nucl. Sci. & Tech. 5(Proc. Actinides2017), 196 (2019).

Nuclear Science and Engineering Center
Papers1) Lessons Learned from the Process Focusing on
Achieving the State of Cold Shutdown ofFukushima Daiichi Nuclear Power Plant
Accident, A. Yoshizawa, K. Oba & M. Kitamura,
Japanese J. Ergonomics 54(3), 124 (2019) (inJapanese).

2) Introduction of AESJ Ethics Committee activities
and issues, K. Oba, IPEJ J. 30(8), 16 (2018) (inJapanese).

36Editorial Board‐ Chief Editor:
Fumiaki TAKAHASHI‐ Editors:
Masao KOMEDA, So AOKI, Masashi KANEKO,
Akiko FURUNO, Shinichiro UESAWA, Keisuke MORITA,
Kyoko OBA, Masatoshi KURETA, Yukio NAKAHARA

Nuclear Science and Engineering Center (NSEC)Japan Atomic Energy Agency (JAEA)
2‐4 Shirakata, Tokai‐mura, Naka‐gun, Ibaraki
319‐1195. JapanE‐mail : nsed‐web@jaea.go.jp
U R L : https://nsec.jaea.go.jp/