FY2021 (2021.4‐2022.3) NSEC
Annual Report

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

November 2022

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, 2022

FY2021 NSEC Annual Report

Table of Contents

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

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

Organization of NSEC∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙ 10

Nuclear and LWR Engineering Division∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙ 11

Nuclear Data Center
Research Group for Reactor Physics and Standard Nuclear Code System
Research Group for Nuclear Sensing
Development Group for Thermal‐Hydraulics Technology
Fuels and Materials Engineering Division∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙ 15

Research Group for Corrosion Resistant Materials
Research Group for Radiation Materials Engineering
Research Group for High Temperature Science on Fuel Materials
Development Group for LWR Advanced Technology
Nuclear Chemistry Division ∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙ 19
Research Group for Radiochemistry
Research Group for Analytical Chemistry
Environment and Radiation Sciences Division ∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙ 21
Research Group for Environmental Science
Research Group for Radiation Transport Analysis
Partitioning and Transmutation Technology Division ∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙∙ 23
Research Group for Partitioning
Research Group for Nuclear Transmutation System
Research Group for MA Transmutation Fuel Cycle

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

FY2021 NSEC Annual Report

PrefaceKUGO TeruhikoDirector General, Nuclear Science and Engineering Center

The Nuclear Science and Engineering Center (NSEC) of the Japan Atomic Energy Agency (JAEA)
aims to conduct research and development to advance the science and technology that supports
the use of nuclear energy and radiation. This annual report provides research highlights and an
overview of the research groups’ activities in the NSEC for Fiscal Year 2021. We hope this annual
report will increase your understanding of the NSEC.
The use of nuclear energy and radiation is supported by the underlying basic science and various
technologies that link science and engineering. As such, we conduct fundamental research toelucidate various phenomena involving atomic nuclei, radiation, and radioactive materials using
our innovative techniques for measurement and analysis. Based on modeling of the observed
phenomena, we develop computer simulation codes and databases for predicting the behavior
of energetic particles, heat and fluid in a reactor core, performance of nuclear fuel and reactor
structural materials, properties and functions of radioactive materials related to their physicaland chemical states, migration behavior of radionuclides in the environment, and the effects ofradiation on the human body.
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 (1) the 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 are applying our innovative technologies to resolve challenges in various
fields, such as industry, environment and medicine.
In 2020, JAEA formulated a vision for the future, JAEA2050+, in order to identify our direction
moving forward. To realize JAEA2050+, the NSEC will serve as a leading center for researchcollaboration and use our research and development capabilities to contribute to advances inscience and technology. We seek your understanding, support, and encouragement in our
research and development activities.

July 2022
1

FY2021 NSEC R&D Highlight

FY2021 NSEC R&D Highlights

The following 6 highlights are selected among various outcomes of the R&D
activities accomplished by the NSEC's 5 divisions in FY2021.

 Nuclear and LWR Engineering Division:"Development of A Low‐Cost Transportable Device for Detecting Nuclear
Materials""Development of Nuclear Data Processing System FRENDY Version 2"
 Fuels and Materials Engineering Division:"Radiation Damage Mechanism in Ceramics Irradiated with Swift Heavy
Ions"
 Nuclear Chemistry Division:"Experimental Approach to Oxidative Degradation of Nuclear Fuel Debris
Induced by Water Radiolysis"
 Environment and Radiation Sciences Division;"Development of Local‐Scale High‐Resolution Atmospheric Dispersion
and Dose Assessment System" Partitioning and Transmutation Technology Division:"Nuclear Fuel Cycle Simulator NMB4.0 Released"

2

FY2021 NSEC R&D Highlight

Development of A Low-Cost Transportable Device for Detecting Nuclear
Materials
KOMEDA Masao, TOH Yosuke
Research Group for Nuclear Sensing
The threat of terrorism is increasing worldwide,and security inspections for radioactive materials
are being conducted at airports and ports. Notably,
terrorism using nuclear materials is much concern
because of its serious damage to society, andnuclear material detection equipment for nuclear
security is becoming increasingly important. The
active method is one of the promising detection
methods. In the method, the object including
nuclear materials is irradiated by the radiation,such as neutron, and induces nuclear reactions. It
detects nuclear materials by measuring theradiation from the nuclear reaction in the object.
While this method has superior detection
sensitivity and accuracy compared to the passive
method, the active device has significant drawbackof being massive and expensive because it requiresa radiation generator with periodically oscillating
intensity.
In this study, we developed a new radiation
generator to realize a low-cost and transportabledevice. In an active device, the intensity of theirradiated radiation must vary periodically.
Therefore, we developed an irradiation device inwhich a radiation source is rotated in order toperiodically change intensity. Californium-252 (Cf252), which emits neutrons, was used as theradiation source.
The developed irradiation device (Fig.1)
incorporates a 31-cm-diameter disk with aradiation source (Cf-252) attached to its periphery,
which can rotate up to 3,000 times per minute. The
irradiation device is much less expensive (about 4
million yen) than conventional radiation generators(which cost about 30 million yen or more because
they use accelerators). In addition, its compact
dimensions (43 cm in width, 35 cm in depth, and 57
cm in height) allow it to be easily moved towherever it is needed.
In order to explain the basic principle of thedetection using a rotating irradiation device,schematics of measurements are shown in Fig.2.
Irradiation neutrons from the radiation source(blue line on the left side of Fig.2) pass through theobject and are measured directly by the detector,
whereas neutrons emitted by the fission reaction(red line on the left side of Fig.2) are measured by
the detector with a slight "delay" at slow rotation
speed because neutrons must be slowed down
before a fission reaction occurs. As the speed

increases (e.g., 3,000 rpm), the "delay" becomes
more noticeable, and the distortion of measured
neutron spectrum can be observed (right side of
Fig.2), which means nuclear materials can be foundby detecting the distortion. A demonstration
experiment was conducted using the developed
irradiation device at Kyoto university, and it was
confirmed that 57 g of uranium-235, which is well
below the IAEA’s significant quantity of uranium235 of 25 kg, could be detected.

Detector
ObjectCf-252(a)(b)
Rotating
irradiation device(c)Fig.1 (a) Device arrangement, (b) Rotating irradiation
device, (c) Disk and radiation source

Fig.2 Schematics of measurements

Reference
1) M. Komeda, et al., Annals Nucl. Energy 159, 108300(2021).

3

FY2021 NSEC R&D Highlight

Development of Nuclear Data Processing System FRENDY Version 2
TADA Kenichi
Research Group for Reactor Physics and Standard Nuclear Code System
The nuclear calculation codes have been used
for many purposes, e.g., reactor design, andshielding analysis. The nuclear data processing
system generates a cross section file which is usedin these nuclear calculation codes. JAEA has
developed the nuclear data processing system
FRENDY to process the Japanese Evaluated Nuclear
Data Library (JENDL) and other nuclear datalibraries since 2013. The first version of FRENDY
was released in March 2019 as an open source
software under the 2‐clause BSD license. FRENDY is
widely used in the world and the OECD/NEA Data‐
Bank uses it to process their evaluated nuclear datalibrary JEFF.
We continued to develop the new functions of
FRENDY, e.g., multi‐group cross section generation
function1), statistical uncertainty quantification forthe probability tables, and perturbation of the ACE
file. Especially, the implementation of the multi‐group cross section generation function for thereactor design code has been required by many
processing code users. We released FRENDY
version 2 including these functions in Jan. 2022
(https://rpg.jaea.go.jp/main/en/program_frendy/).
As shown in Fig.1, FRENDY version 2 cangenerate a multi‐group cross section file from an
ACE file1). The ACE file is used for many continuous
energy Monte Carlo codes, e.g., MCNP, PHITS, andSerpent. Furthermore, many institutes release ACE
files from their website. The users can generate themulti‐group cross section files from these existing
ACE files.
Critical benchmark calculations and a PWR pin‐cell calculation were used for the verification of themulti‐group cross section generation function in
FRENDY. The multi‐group cross section files weregenerated by FRENDY and NJOY using identicalprocessing conditions. The comparison of the k‐effective values using the multi‐group cross section
files processed by FRENDY and NJOY is shown in
Table 1. As shown in Table 1, the k‐effective values
using cross section files processed by FRENDY show
good agreement with those by NJOY.
We implemented unique functions in FRENDY
version 2, e.g., automatic setting of the backgroundcross section and explicit consideration of theresonance interference effect. These features will
increase the value of FRENDY and attract not only
current users but also new users.

Evaluatednuclear data file
Linearization

FRENDY Version 2

FRENDY Version 1…
Probability‐table
generation
ACE file generation
ACE file
Multi‐group XS
generation
Multi‐group XS fileFig.1 Processing flow of multi‐group cross section(XS) generation in FRENDY version 2.

Table 1 Comparison of k‐effective values using themulti‐group cross section files processed by
FRENDY and NJOY.
Experiments /Calculation case

FRENDY

NJOY

Relativedifference

Jezebel

0.99832

0.998290.003%

Jezebel-Pu

0.998420.998380.004%

Godiva0.99777

0.997760.001%

Jezebel-233

0.99932

0.99934-0.002%

Flattop-U

0.997430.997230.020%

Flattop-Pu

0.998440.998270.017%

Flattop-233

0.998140.99801

0.013%

Thor

0.997850.99790-0.005%PWR pin-cell1.40755

1.40751

0.003%

Reference
1) A. Yamamoto, K. Tada, et al., J. Nucl. Sci. Tech. 58(11),1165 (2021).

4

FY2021 NSEC R&D Highlight

Radiation Damage Mechanism in Ceramics Irradiated with Swift Heavy Ions
ISHIKAWA Norito1, TAGUCHI Tomitsugu2, OKUBO Nariaki1
1 Research Group for Radiation Materials Engineering
2 National Institutes for Quantum Science and Technology (QST)
When ceramics are irradiated with swift heavy
ion beams (having more than tens of MeV energy),
nanostructures called ion tracks are created along
the ion paths. In many ceramics the size of the ion
tracks can be predicted by the thermal spike theory.
However, in some ceramics the size of the ion
tracks observed by the experiment was found to besmaller than that predicted by the theory.
Surprisingly, such size discrepancy was remarkablein ceramics having high radiation‐resistance. Whatis the reason for the failure of the theory? Oursystematic study of surface nanostructure(nanohillock) has revealed the reason1).
According to our transmission electron
microscopy observation (Fig.1)1), the ion track size
is smaller than the nanohillock size in CeO2 which isone of the highly radiation‐resistant ceramics,
while the size difference is very small in ceramics
having low radiation‐resistance.
A likely process in ceramics having low
radiation‐resistance is described in Fig.2(a)2). Firstly,(1) a part of the surface protrudes during local
melting along the ion path and secondly, (2) themolten region turns into damaged region during
rapid cooling. This process is very likely, since thenanohillock size is found to be similar to the ion
track size in ceramics having low radiation‐
resistance3).
In contrast, in ceramics having high radiation‐
resistance (Fig.2(b)2)), (1) a part of the surface
protrudes during local melting along the ion path,(2) the molten region partially recrystallizes
resulting in shrinkage of the damaged region andfinally (3) the protruded part near surface
recrystallizes. This hypothesis can be validated by
Fig.1 showing that the ion track is smaller than the
nanohillock. This means that ion tracks rapidly
shrink in highly radiation‐resistant ceramics owing
to extremely fast recrystallization. It also showsthat the recrystallization process is not assumed in
the conventional theory1,4). The well‐aligned
atomic layers inside nanohillocks (Inset of Fig.1)
further support the recrystallization process which
is depicted in the third process of Fig.2(b). In
conclusion, the origin of the high radiation‐
resistance is high recrystallization capability.

Fig.1 Nanostructure created in CeO2 irradiated withswift heavy ions.2) The inset shows themagnified image of a nanohillock.

Fig.2 Nanostructure formation process by highenergy heavy ions in (a) ceramics having low
radiation‐resistance and in (b) ceramics having
high radiation‐resistance.2)

Reference
1) N. Ishikawa, et al., しょうとつ J. Atomic Collision Res.
18(3), 43 (2021) (in Japanese).
2) N. Ishikawa, et al., Quantum Beam Sci. 4(4), 43 (2020).
3) N. Ishikawa, et al., J. Applied Phys. 127, 055902 (2020).
4) N. Ishikawa, et al., Nanotechnology 28(44), 445708(2017).

This work was supported by JSPS KAKENHI Grant
Number 20K05389.

5

FY2021 NSEC R&D HighlightExperimental Approach to Oxidative Degradation of Nuclear Fuel Debris
Induced by Water Radiolysis
KUMAGAI Yuta1, KUSAKA Ryoji1, NAKADA Masami2, WATANABE Masayuki1, AKIYAMA Daisuke3,
KIRISHIMA Akira3, SATO Nobuaki4, SASAKI Takayuki5
1 Research Group for Radiochemistry
2 Collaborative Laboratories for Advanced Decommissioning Science (CLADS)
3 Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
4 Center for Fundamental Research on Nuclear Decommissioning, Tohoku University
5 Department of Nuclear Engineering, Kyoto University
U-Zr oxide solid solution proceeded to aremarkable degree (USZrO21600-O) showed muchless U dissolution and no Raman signal of uranyl
peroxides. This finding indicates that formation of
the oxide solid solution of Zr with UO2 improves the
durability of fuel debris against H2O2 reaction.

Fuel debris generated in the accident at
TEPCO’s Fukushima Daiichi Nuclear Power Station
remains in the reactors, and substantial time andeffort will be required until retrieval of the debris.
The debris has been most likely exposed to water
since the accident. The contact with water would
bring on degradation of the debris matrix due tothe radiolysis of water. The water radiolysis
generates oxidants such as hydrogen peroxide(H2O2), which can oxidize uranium to hexavalent
U(VI). According to previous studies of uranium(IV)oxide (UO2) and spent fuels1), the U oxidation
proceeds at the interface to water and the matrix
gradually dissolves because U(VI) has higher watersolubility than U(IV). Hence, to examine possible
degradation processes of fuel debris, we carriedout leaching experiments using simulated fueldebris2).
The simulated debris samples were preparedfrom powders of UO2, stainless steel (SUS304), andzirconium metal (Zr) or oxide (ZrO2) by heat
treatments under various conditions (Table 1).
After analyzing the phase composition of thesamples, the simulated debris samples were
immersed in aqueous H2O2 solution for up to 30
days. H2O2 was added since it is the oxidant
generated by water radiolysis that has major
impact on the U oxidation. After certain periods ofimmersion, the samples were analyzed by Raman
spectroscopy as well as chemical analysis of theleached elements.
The analysis of the leached elements showedsignificant dissolution of U from the samples. The
reaction of H2O2 concurrently induced precipitationof uranyl peroxides, UO2(O2)·nH2O (n = 2 or 4).
These two processes made the dissolved U
concentration once increase and then decrease
with leaching time (Fig.1(a)). The formation of
uranyl peroxides was clearly confirmed by the
Raman spectroscopy (Fig.1(b)). These results
demonstrate that uranyl peroxides are possible
alteration products of fuel debris from H2O2
reaction.
In contrast, the sample in which formation of aThis work was supported by the Japan Atomic
Energy Agency Nuclear Energy S&T and Human
Resource
Development
Project
throughconcentrating
wisdom,
Grant
Number[JPJA18P18071886].
Table 1 Examples of simulated debris samples
prepared in this study.

Fig.1 (a) U concentrations in the leachate and (b)Raman spectra of uranyl peroxides formed on
USZr1600-O.

Reference
1) T.E.Eriksen, et al., J Nucl. Mater. 420(1-3), 409 (2012).
2) Y. Kumagai, et al., J. Nucl. Sci. Tech. 59(8), 961 (2022).

6

FY2021 NSEC R&D Highlight

Development of Local-Scale High-Resolution Atmospheric Dispersion andDose Assessment System
NAKAYAMA Hiromasa
Research Group for Environmental Science
We developed a local-scale high-resolution
atmospheric dispersion and dose assessment
system (LHADDAS)1) for safety and consequenceassessment of nuclear facilities and emergency
response to nuclear accidents or deliberate
releases of radioactive materials in built-up urban
areas in cooperation with Center for Computational
Science and e-Systems (CCSE).
This system comprises of three parts: 1)
Preprocessing of input files, and main calculation
by a local-scale high-resolution atmosphericdispersion model using large-eddy simulation(LOHDIM-LES)2). 2) A real-time urban dispersion
simulation model based on a lattice Boltzmann
method (CityLBM)3). 3) Postprocessing of dose
calculation by a simulation code powered by latticedose-response functions (SIBYL)4).
We examined the performance of LHADDAS
using the following two application cases from ourprevious studies. The first case involved acontrolled tracer plume dispersion in the vicinity ofan actual nuclear facility and building arrays. The
second was about tracer gas dispersion in an actual
central urban district. Here, we showed the first
application case of the LOHDIM-LES simulation of
the actual tracer plume dispersion of radionuclides
released from the nuclear fuel reprocessing plant in
Rokkasho, Japan as an example. The simulation
period was from 09:00–19:30 Japan Standard Time
(JST) on 17 June 2008. Figure 1 shows an
instantaneous shot of the tracer plume released
into the atmosphere from a stack at 10:40 JST on
17 June. Figure 2 compares the LOHDIM-LES resultswith the monitoring post (MP) data. Consequently,
the outcome demonstrated an intermittent
increase in the air dose rates at MP2. These rates
frequently showed higher peaks at MP3 than thoseat MP2. Therefore, the main part of the plume wastransported above MP3. These time variation
patterns at the different MPs were simulated wellby LOHDIM-LES integrated with the SIBYL module.
The model performance of LOHDIM-LES and
CityLBM was also demonstrated with the datacollected during the urban field experiments forthe second application case.
LHADDAS has broad functionalities andperforms extremely well in simulating turbulent
flows, plume dispersion, and dry deposition underrealistic meteorological conditions. It can simulate
real-time tracer dispersion using a locally mesh-refined lattice Boltzmann method. Moreover, it canestimate the air dose rates of radionuclides from airconcentration and surface deposition taking into
consideration the influence of individual buildings.

Fig.1 Instantaneous plume dispersion field at
Rokkasho Reprocessing Plant at 10:40 JST 17
June.

Fig.2 Time series of the air dose rate at the MPs
during the period from 09:00 JST to 19:00 JST 17
June 2008.

Reference
1) H. Nakayama, et al., J. Nucl. Sci. Tech. 59(10), 1314 (2022).
2) H. Nakayama, et al., J. Nucl. Sci. Tech. 58(9), 949 (2021).
3) N. Onodera, et al., Boundary-Layer Meteor. 179(2), 187(2021).
4) D. Satoh, et al., PLoS ONE 16(1), e0245932 (2021).

7

FY2021 NSEC R&D Highlight

Nuclear Fuel Cycle Simulator NMB4.0 Released
NISHIHARA Kenji1, OKAMURA Tomohiro2, KATANO Ryota1, OIZUMI Akito1, NAKASE Masahiko2,
ASANO Hidekazu2, TAKESHITA Kenji2
1 Research Group for Nuclear Transmutation System
2 Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology
Currently in Japan, various reactor types andreprocessing technologies to reduce the waste load
are being developed for future nuclear power
utilization. In order to start full-scale development
for the realization of these technologies, it isnecessary to evaluate whether future introduction
scenarios can be envisioned and how much thebenefits and costs would be if they were introduced.
For this evaluation, future scenarios with various
technologies are set up, and quantity is evaluatedassuming these scenarios, which are called nuclear
fuel cycle simulations. So far, there are no publicly
available general-purpose simulators in Japan, andmany excellent simulators in other countries are
not open. JAEA and Tokyo Tech have jointly
developed NMB4.01) (NMB stands for Nuclear
Material Balance), a (1) fast, (2) versatile, and (3)flexible simulator, and we released it on thewebsite (https://nmb-code.jp). The features of thissimulator are described below.
(1) High speed: Conventional simulators havemainly analyzed the burnup changes of about 20 to
30 nuclear materials such as uranium in a nuclear
reactor, but in order to accurately evaluate thegeneration and disposal of radioactive waste, theNMB can analyze about 150 fission products. To
analyze the burnup changes of these materials, afast solution method has been developed andequipped.
(2) Versatility: The NMB can analyze almost allprocesses in nuclear power generation (Fig.1). For
reactors, the database has been developed to allow
analysis of light water reactors and future-type
reactors. For the nuclear fuel cycle, an extensive
analytical model and database for temperature ingeological disposal of radioactive waste have beendeveloped, which is not included in most of theother simulators. This model allows to evaluate
repository size.
(3) Flexibility: The future of nuclear power
utilization in Japan is very ambiguous due touncertainties in the replacement of light water
reactors, delays in the development of fast reactors,
and difficulties in selecting a geological disposal site.
Therefore, we have designed the NMB capable ofanalyzing a variety of scenarios, such as withdrawal
or continuation of nuclear power utilization, andchanges in the timing of FBR introduction. (Analysis

example: Fig.2)
We are now calling for a wide range of users
and developers to join Team NMB. The team islooking for users such as universities, research
institutes, manufacturers, and electric power
utilities, etc., to help us plan R&D and
implementation strategies for future nuclear
reactors and nuclear fuel cycle technologies for thesustainable use of nuclear energy.

MA Inventory（t）

Capacity（GWe）

Fig.1 Nuclear fuel cycle handled by NMB4.0
60
50
40
30
20
10
0
200

MOX in LWR

50

ADS 5 units

FBR

LWR

Case without ADS

150
100

FR

ADS fuel cycle
MOX SF from LWR
UO2SF

MA storage
Pu storage
FBR fuel cycle
Glass waste

0

2150
2140
2130
2120
2110
2100
2090
2080
2070
2060
2050
2040
2030
2020
2010
2000

Fig.2 Example of analysis (reduction of minor
actinides by ADS in FBR transition scenario)

Reference
1) T. Okamura, R. Katano, et al., EPJ Nucl. Sci. Tech. 7, 19(2021).

8

FY2021 NSEC Group Activity

FY2021 NSEC Group Activities

The NSEC of JAEA consisted of 15 Groups in FY2021.

Since April 2022, the NSEC has been re‐organized from 15 Groups of 5 Divisions to 11
Groups of 3 Divisions: “Research Group for Reactor Physics and Standard Nuclear Code System” and“Development Group for Thermal‐Hydraulics Technology” have been merged
into “Research Group for Reactor Physics and Thermal‐Hydraulics Technology”;“Nuclear and LWR Engineering Division” has been renamed “Nuclear Scienceand Reactor Engineering Division”;
 “Development Group for LWR Advanced Technology” has been splited andmerged into “Research Group for Radiation Materials Engineering” and“Research Group for High Temperature Science on Fuel Materials”;
 “Research Group for Radiochemstry” and “Research Group for Analytical
Chemistry” have been merged into “Research Group for Nuclear Chemistry”;“Nuclear Chemistry Division” and “Environment and Radiation Sciences Division”
have been merged into “Chemistry, Environment, and Radiation Division”;
 “Partitioning and Transmutation Technology Division” has been abolished; “Research Group for Partitioning” and “Research Group for MA
Transmutation Fuel Cycle” have been merged into “Research Group for
Nuclear Fuel Cycle Science” of “Fuels and Materials Engineering Division”;
 “Research Group for Nuclear Transmutation System” has been transferredto “Nuclear Science and Reactor Engineering Division”.

9FY2021 NSEC Annual Report

Organization of NSEC

（as of October 2022）

URL: https://nsec.jaea.go.jp/organization/en_index.html
10

FY2021 NSEC Group Activity

Nuclear Data Center
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 themission, we engage in research works on nuclear
data measurement, nuclear theories, and nuclear
data evaluation related to nuclear reaction andstructure, collaborating with nuclear data
researchers and organizations in Japan as well as in
the world. The evaluated nuclear data have been
compiled into databases called JENDL (Japanese
nuclear data library). The JENDL files are available
from our website ( http://wwwndc.jaea.go.jp ).

accumulated but their uncertainties are still large.
With the theoretical models of relativistic
quasiparticle random-phase approximation forbeta-decay and a statistical model for neutron
emission, the delayed neutron branching ratios
were calculated for neutron rich unstable nuclei
over the periodic table. The calculated results werein good agreement with available experimental
data with reducing the root mean square deviationcomparing with the preceding works.3) This work is
expected to contribute to further studies on the
nucleosynthesis as well as the accuracy
improvements of delayed neutron emission data
for fission products.

Neutron Capture Cross Section
Measurement with Activation
MethodRelease of JENDL-5
JENDL-5, the latest version of JENDL, wassuccessfully released in December 2021. It was amain target of the 3rd midterm (2015-2021) plan of
Nuclear Data Center. JENDL-5 aimed to meetvarious needs in nuclear energy applications not
only for nuclear reactor development but also for
nuclear backend issues such as decommissioning ofreactors and nuclear waste management. Largeamount of neutron induced reaction data from lightto heavy nuclides were revised and the number of
nuclides nearly doubled. The performance fornuclear reactor and neutron shielding was
improved by feedback of repeated benchmark tests.
To meet additional needs of radiation applications,its previously released special-purpose libraries
were revised and integrated into JENDL-5. JENDL-5
consists of 11 sublibraries that include data ofneutron, charged-particle and photon induced
reactions; neutron thermal scattering law, fission
yield and decay data; and atomic related data.

Neutron irradiated data using a fast neutron source
reactor ‘YAYOI’ were revisited. By the analysis of
gamma-rays from irradiated samples, the neutron
capture reaction rates of technetium(Tc)-99 werededuced. The present measurement had a large
sensitivity on the cross sections in the neutronenergy region of 10-100 keV, where the recent
nuclear data libraries of ENDF/B-VII.0, ENDF/BVIII.0 and JENDL-4.0 provided rather inconsistentcross sections. The obtained data revealed that theevaluated cross section in JENDL-4.0 was the mostfavorable among them.1)

TOF Measurement of Neutron
Induced Reactions with ANNRI
Resonance parameters of niobium(Nb)-93 below
400 eV were deduced from measurements ofneutron capture and transmission ratios with
ANNRI installed at J-PARC with a time of flight (TOF)
method. The Nb neutron capture cross section isimportant in activation evaluation because Nb isused in stainless steel for reinforcement andcreates long-lived radioactive Nb-94 with half-life of
20 thousand years by neutron capture reaction. The
present results suggested JENDL-4.0 evaluation of
the neutron capture cross section at thermal
neutron energy was overestimated by 18 %.2) The
obtained resonance parameters were adopted in
JENDL-5.

Reference
1) S. Nakamura, et al., J. Nucl. Sci. Tech. 58(12), 1318 (2021).
2) S. Endo, et al., J. Nucl. Sci. Tech. 59(3), 318 (2022).
3) F. Minato, et al., Phys. Rev. C 104(4), 044321 (2021).

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

Theoretical Model Prediction for
Beta-delayed Neutron Emission
Beta-delayed neutron emission is important not
only for nuclear reactors but also for
nucleosynthesis in the universe. Experimental data
for the delayed neutron emission have been

11

FY2021 NSEC Group Activity

Research Group for Reactor Physics and Standard Nuclear Code
SystemThe role of nuclear codes is increasing with rapid
progress in computer technology. It enables toevaluate in detail the energy and spatial
distribution of neutrons and photons emitted after
fission reactions in a nuclear reactor. Important
properties such as criticality and radioisotope
production rate etc. can be deduced from theseneutronics calculations by these nuclear codes.
We are developing standard nuclear codes tosupport and advance nuclear energy technology.
The main codes are MVP and FRENDY. We are also
performing integral tests for the JENDL project withthe codes. We are also developing an advanced
neutronics/thermal-hydraulics coupling simulation
system for enhanced safety of light water reactors(LWRs) and improvement of LWR design. The
project started from 2020 JFY. This fiscal year wehave developed an Interface Program to
Accommodate
Coupling
Simulationforneutronics/thermal-hydraulics IPACS.

gives better than or the same prediction accuracy
as JENDL-4.07) in many test cases for the critical andshielding experiments.8)

IPACS

IPACS9) is an interface program for the advanced
neutronics/thermal-hydraulics coupling simulation
system. A prototype simulation system
MVP/NASCA was developed by using IPACS. Thissystem is the first step for the development of theadvanced coupling simulation system. The
objectives of this system are to find the issues ofcoupling simulations and to implement the current
methodology used for neutronics (MVP) andthermal-hydraulics (NASCA) coupling. NASCA10) is a
subchannel analysis code for thermal-hydraulics
analysis. As the next step, we will replace thesubchannel code with a CFD code such as
JUPITER11) developed at JAEA. IPACS can beobtained from RIST.
Reference

FRENDY

1) K. Tada, et al., JAEA-Data/Code 2018-014 (2019).
2) https://rpg.jaea.go.jp/main/en/program/ (accessed2022-11-08).
3) https://rpg.jaea.go.jp/main/en/program_frendy/(accessed 2022-11-08)4) https://wwwndc.jaea.go.jp/jendl/j5/j5.html (accessed2022-11-08)5) https://www.oecdnea.org/jcms/pl_24498/international-criticality-safetybenchmark-evaluation-project-icsbep (accessed 202211-08)
6) K. Yokoyama, et al., JAEA-Research 2018-011 (2019) (inJapanese).
7) K. Shibata, et al., J. Nucl. Sci. Tech. 48(1), 1 (2011).
8) K. Yokoyama, 2022 Annual Meeting of AESJ, 1A_PL04(2022) (in Japanese).
9) https://rpg.jaea.go.jp/main/ja/program/ (in Japanese)(accessed 2022-11-08).
10) A. Hotta & K. Nozaki, Trans. Jpn. Soc. Mech. Eng. B
76(763), 454 (2010).
11) S. Yamashita, et al., Mech. Eng. J. 4(3), 16-00567 (2017).

FRENDY is a nuclear data processing code.1) It
enables processing of evaluated nuclear data suchas JENDL. FRENDY version 1 was released in March
2019 as an open-source code from our website.2)
FRENDY version 1 generates the ACE files which areused for Monte Carlo codes such as PHITS and
MCNP. FRENDY version 23) was released in January
2022. It implements new capabilities: theestimation of statistical uncertainty in probability
table generation for unresolved resonance crosssections, the generation of multigroup constants,
etc. FRENDY version 2 can be also downloaded fromour website.3)

Integral Tests for JENDL-5

JENDL-5 was released in December 2021.4) Since
2018, we have performed integral tests ofpreliminary and release versions of JENDL-5 forcritical and shielding experiments. The test
calculations were done for experiments mainly in
the International Criticality Safety Benchmark
Evaluation Project (ICSBEP)5) handbook andconducted at JAEA. The test calculations for middleand large-sized fast systems were done for integral
experiments used for generation of the unified
cross section data set of ADJ2017.6) The shielding
benchmark tests were done mainly for FNS
experiments at JAEA and OKTAVIAN experiments at
Osaka University. We have confirmed that JENDL-5

Contact (Group Leader):NAGAYA Yasunobu
nagaya.yasunobu@jaea.go.jp

12

FY2021 NSEC Group Activity

Research Group for Nuclear Sensing
Neutron is a powerful tool in the non-destructive
analysis (NDA), since it has exceptional ability topenetrate high-density materials, and can induce
fission and radiative capture reaction. Despite
being a mature technique, further improvements in
NDA are required and enable us to meet thedistinctive demands in many fields. We have,therefore, developed the NDA techniques using theneutron interrogation to apply for nuclear andradioactive materials.

This research was implemented under thesubsidiary for nuclear security promotion of MEXT.

Non-destructive Quantitative
Analysis of the Difficult-tomeasure radionuclides: 107Pd and99
Tc
For radioactive material waste management,
reliable quantification of radioactive nuclides is
especially important. A non-destructive analyticalscheme applicable to the difficult-to-measurenuclides of 107Pd and 99Tc, which emit no or almost
no decay gamma-rays and whose half-lives are toolong to be decayed out during a human lifetime,
was developed. The analytical scheme is composedof a sophisticated instrument named ANNRI, which
can perform measuring of gamma rays by a Ge
detector array coupled with Time of Flight (TOF)
measurement, and a high-intensity pulsed neutron
beam generated at the Japan Proton Accelerator
Complex (J-PARC) and can simultaneously perform
TOF-PGA as well as PGA. The analytical capability
was evaluated by applying to simulated samples of
the Tc-platinum group metals obtained by thegroup partitioning process of spent nuclear fuels. It
was confirmed that, although PGA cannot
accurately analyze either of the nuclides in thesimulated samples, TOF-PGA can analyze 107Pd aswell as 99Tc3). The TOF-PGA measurement
technique could be widely used for the nondestructive analysis of 107Pd and 99Tc in nuclear
wastes.

Development of an Active Neutron
Non-destructive Analysis System:
Active-N
The different analytical methods give us
complementary information, which are particularly
useful for the quantification of special nuclear
materials and minor actinides (MA) in highly
radioactive nuclear materials (HRNM), including
spent fuel and MA transmutation fuel. JAEA and the
Joint Research Centre of the European Commission
are collaborating to develop an active neutron NDA
system for nuclear non-proliferation and nuclear
security. We have developed a novel NDA system:
Active-N (Fig.1)1) by combining active neutron
methods, as listed below, to deal with the difficult
problem of measuring HRNM.
(1) Differential Die-away Analysis (DDA)(2) Prompt Gamma-ray Analysis (PGA)(3) Neutron Resonance Transmission Analysis(NRTA)The Active-N system was deployed at nuclear fuelcycle safety engineering research facility in JAEA.
The Active-N system performance was evaluated bymeasuring of a simulated HRNM2). The results
indicate that the Active-N system has enoughcapabilities to detect and quantify of HRNM.

Reference
1) Y. Toh, et al., Proc. the INMM & ESARDA Joint Annual
Meeting (2021).
2) K. Furutaka, et al., Proc. the INMM & ESARDA Joint Annual
Meeting (2021).
3) Y. Toh, et al., Anal. Chem. 93(28), 9771 (2021).

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

Fig.1 Active neutron non-destructive analysis
system: Active-N

13

FY2021 NSEC Group Activity

Development Group for Thermal-Hydraulics Technology
For the establishment of thermal-hydraulics
numerical simulation methods for multi-phase flow,
we are developing multi-phase CFD numericalsimulation codes, TPFIT, ACE-3D, and JUPITER, andmeasurement techniques to obtain thermalhydraulics data. In addition, we are performing
thermal-hydraulics experiments to constructvalidation databases. These advanced techniques
are applied to the research activities for improving
the safety of the LWRs and providing informationon the decommissioning process of TEPCO's
Fukushima Daiichi NPS.

Research of Hydraulics Behavior in
Venturi Scrubber
The filtered venting system is used to prevent therelease of radioactive materials in severe accidents.
We developed a numerical simulation method
based on TPFIT to evaluate the performance of the
Venturi scrubber, which is one of the componentsof the filtered venting system. In addition, we
performed various experiments to validate thedeveloped simulation method. Figure 2 shows anexample of the predicted result in the Venturi
scrubber2). The result of visualized experiments is
also shown. In the visualized result, the injectedliquid formed a liquid bridge. We confirmed theformation of the same liquid bridge by thenumerical simulation. This liquid bridge captures
small radioactive particles effectively; therefore,
the prediction of liquid bridge formation isimportant to evaluate the performance of the
Venturi scrubber. We will evaluate thedecontamination factor for the Venturi scrubber byusing these results.

Numerical Simulation of Oxidation
under Severe Accident Conditions
JUPITER can simulate fuel debris melting andrelocation behavior without assumptions or
simplification. Besides, JUPITER can performchemical reactions such as zirconium-water andeutectic reactions. As one of the examples ofcalculation by JUPITER, we performed a numericalsimulation of oxidation simulation on the zircaloy
surface (Fig.1)1). This simulation evaluated the time
evolution of the oxide layer thickness on thezircaloy by the newly developed oxidation
simulation model. In Fig.1, we visualized the growthof the oxide layer thickness. The oxide layer
thickness increases as time proceeds, and thesteam concentration decreases as the growth ofthe oxide layer. We confirmed that the modified
JUPITER reasonably simulates the fundamentaloxidation process.

Fig.2 Predicted and Visualized HydraulicBehavior in Venturi Scrubber
Reference
1) S. Yamashita, et al., Proc. NURETH-19 35516 (2021).
2) S. Uesawa, et al., 2022 Annual Meeting of AESJ 1E15
(2022) (in Japanese).

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

Fig.1 The time change of the oxide layer
thickness

14

FY2021 NSEC Group Activity

Research Group for Corrosion Resistant Materials
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 focus on the corrosion mechanism todevelop the methods of corrosion prediction andprevention. Through these research activities, we
contribute to the improvement of the reliability of
nuclear facilities.

phenomena of ions quantitatively reproduced thisbehavior. It was indicated that in the low potential
range (see Fig.2), Cl- was considered to be the majoranionic species transported into the crevice andσcrev increased with Eext. In high potential range,transpassively generated HCrO4− began to migrate
into the crevice. Since HCrO4− act as strong oxidizer
and oxidize metal cation to precipitate them as
metal oxide eventually decreased σcrev value.

Researches on Corrosion Behaviorof Tantalum in Sodium Hydroxide
Solution
The corrosion behavior of tantalum used in nuclear
fuel reprocessing equipment in sodium hydroxide(NaOH) solution, which is expected to be used indecontamination to reduce worker radiation
exposure, was investigated by immersion corrosion
tests, and the mechanism of aging degradation wasstudied. The immersion corrosion tests showedthat the corrosion rate (CR) increased with NaOH
concentration. Moreover the CR peaked and thendecreased with immersion time (Fig.1). The time topeak was shorter for higher NaOH concentrations.
Scanning electron microscopy, Raman analyses and
X-ray diffraction patterns of the surface of thespecimens after the tests showed the corrosion
product (Na8Ta6O19) film formation and the film
growth with immersion time. And ourelectrochemical measurement suggested that thechange in CR with time should be explained by thefilm growth and concluded that the film growth
inhibits corrosion reactions.

Fig.1 Corrosion rate of Ta in NaOH solution.

Researches on Corrosion Behaviorof Stainless Steel in HighTemperature Water

Fig.2 Change in electrical conductivity within
the crevice and potential with time.

The effects of electrochemical corrosion potential(ECP) on the water chemistry within a crevice ofType-316L stainless steel was investigated. In-situ
measurements of the electrical conductivity of thesolution within a 15-μm-gap crevice (σcrev) wereconducted in high temperature water (288 °C
containing 10 ppb of Cl− as major anionic
impurities). An increase in the ECP at the externalsurface of the crevice specimen (Eext) fromapproximately −0.49 V to 0.15 V resulted in an
increase in σcrev (measured at 21 mm from thecrevice mouth) from 12 μS/cm to >300 μS/cm(Fig.2). A further increase in Eext led to a decline inσcrev. Finite element model analysis of the crevice
water chemistry taking into account theelectrochemical reaction and transportation

Reference
1) Y. Ishijima, et al., Mater. Trans. 63(4), 538 (2022).
2) Y. Soma, et al., Corrosion 78(6), 503 (2022).

Contact (Group Leader):KATO Chiakikato.chiaki16@jaea.go.jp
15

FY2021 NSEC Group Activity

Research Group for Radiation Materials Engineering
In our group, a wide variety of nuclear materials,
including the materials which are under theconsideration of future use, have been studied forthe purpose of deepening the understanding on
their radiation tolerance. In-situ observation is oneof the most useful techniques for material
irradiation studies. Especially, for modeling of the
microstructural evolution of irradiated materials,
systematic irradiation studies have been
performed1),2). In addition, in order to apply foradvanced nuclear systems, we are exploring not
only a novel advanced material but also an
innovative technology for material fabrication3).

which were fabricated by AM in order tounderstand the effect of high dose ion irradiation
on microstructural evolution. Figure 2 (a) and (b)show the cross-sectional TEM images after
irradiation at 773 K up to over 300 dpa, indicatingthat small cavities with the size of less than 10 nm
formed in both arc-melted and selective laser
melted (SLMed) MEAs. By comparing this resultwith that of arc-melted and SLMed 316L SSs, thecavity formation was suppressed significantly.

Point-defect migration investigatedusing in situ high-voltage electron
microscopy
Modeling the microstructural evolution ofirradiated materials requires knowledge of the
migration energies of point defects, which are
induced by the impact of energetic particle
radiation. In our group, we have estimated themigration energies of interstitials and vacancies
formed as point defect pairs by observing theevolution behavior of self-interstitial atom (SIA)
clusters in electron-irradiated α-iron using an insitu high-voltage electron microscopy. According toa rate-theory analysis, the interstitial or vacancy
migration energy can be estimated from thetemperature dependence of the peak cluster
number density or the cluster growth rate,
respectively. Figure 1 (a) and (b) show theestimated interstitial1) and vacancy2) migrationenergies, respectively. The values are concordant
with those calculated from the first-principles
studies.

Fig.1 Estimation of migration energies of (a)interstitials (Eim)1) and (b) vacancies (Evm)2) in α-iron.
Fitting conditions: (a) above 200 K, whereinterstitials are thermally mobile, and (b) the
maximum growth rate of isolated SIA clusters at
each temperature.

Fig.2 Cross-sectional TEM image of ion-irradiated
MEAs fabricated by (a) arc-melting, (b) selective
laser melting.

Ion irradiation study on additive
manufactured low activation
medium entropy alloys

Reference
1) Y. Abe, et al., Philos. Magazine 101(14), 1619 (2021).
2) Y. Abe, et al., Philos. Magazine 102(12), 1173 (2022).
3) “Development of new reduced activation HEAs by additive

Some concentrated solid solution alloys (CSAs) andmedium entropy alloys (MEAs) have attractive
properties such as a high radiation tolerance andcorrosion resistance at elevated temperatures.
These new alloys are, therefore, expected to be a
promising candidate as structural materials foradvanced nuclear systems. On the other hand,additive manufacturing (AM) is an emerging
technology that can provide many benefits such as
freedom of design, waste minimization and theability to manufacture complex structures, and theactive use of AM in the nuclear fields is now underconsideration. In this study, we focused on MEAs

manufacturing method”, JFY2021 progress report.
* This work was supported by MEXT Innovative Nuclear Research and Development
Program Grant Number JPMXD0220354336.

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

16

FY2021 NSEC Group Activity

Research Group for High Temperature Science on Fuel Materials
We treat issues on nuclear fuel materials for bothlight water reactors and advanced reactors in the
future. Experimental work on uranium and nonradioactive materials is carried out in the Researchbuilding No.4, with various heating devices andanalytical apparatus. That on transuranium
elements (TRU: Pu and minor actinides) is
performed at TRU-HITEC, consisting of speciallydesigned hot cells and glove box with highly
purified argon atmosphere. We also take advantage
of computer science to understand or predict
phenomena concerning the fuel materials at hightemperatures and under irradiation conditions.

Example of the temperature curve and the laser
power pattern of a sintered Er0.3Zr0.7N specimen isshown in Fig.2. The advantages of this method arevery short measurement time (0.1 sec) and thesmall specimen size (3 mm in diameter), as well as
no crucible. Now we apply this system to thelanthanide-zirconium nitride solid solutions todetermine the liquefaction temperature asfunctions of composition and nitrogen partialpressure, aiming for application to the TRU nitride
fuel in near future.

Advanced Technique for Melting
Temperature Measurement
For the safety analysis of fuel materials, melting
point (Tm) is one of the essential properties. In caseof the nitride fuel for minor actinide transmutation
containing ZrN or TiN as inert matrices, its Tm is
expected to be extra high (over 3,000 °C) andcannot be measured by the conventional method
using induction furnace and tungsten crucible
because of the mutual reaction between the
crucible and nitride specimen. In addition, melting(liquefaction) of the nitrides is not congruent but
decomposition into liquid metal saturated withnitrogen and N2 gas. Therefore, the liquefaction
temperature strongly depends on the nitrogenpartial pressure of the system. Recent advanced
technique for Tm measurement using laser spot
heating and high-speed infrared spectrometer is aunique method that can solve the above problem.
The measurement system was assembled in
Research building No.4 for optimization of
measurement conditions and analysis method.1)
Schematic of the system and the appearance areshown in Fig.1. YAG laser shot forms a liquid phasein the limited area (a few mm in diameter) on thesurface of disk-shaped specimen, and the radiation
spectrum of this area is recorded at high speed.
Semiconductor laser is used for preheating thespecimen to avoid fracture by thermal shock.
The key technique of this method is to determine
the emissivity and temperature simultaneously byanalyzing the spectrum. The monochromaticradiation thermometer is used only to determine
the timing of liquid phase formation (thermal arreston the temperature curve). After optimization of
the analysis, we successfully demonstrated the Tm
measurement of tantalum and molybdenum,
known as high Tm metals, within the uncertainty ofseveral ten degrees Celsius.

Fig.1 Schematic and appearance of the melting
point measurement system.

Fig.2 Example of temperature curve and laser
power pattern as a function of time.
Vertical axis does not show the actual
specimen temperature.
Reference
1) T. Iwasa & T. Arima, JAEA-Tech. 2021-036 (2022) (inJapanese).

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

17

FY2021 NSEC Group Activity

Development Group for LWR Advanced technology
Our group has been conducting research programs to
improve LWR safety by evaluating the rationality of
regulation standards, safety margin estimation,
accident management, etc., from a scientific point ofview. Through this, we aim to advance the safety
technology in LWR, and also contribute to accelerationof the decommissioning of Fukushima Dai-ichi Nuclear
Power Station (1F). We mainly focus on fission product(FP) behaviors under severe accident (SA) conditions,and development of accident tolerant fuel (ATF)
cladding.

coated cladding with 10 micrometer thickness of Cr
phase on its outer surface, were cut into 20 mm lengthand applied for the tests*. To investigate the oxidation
behavior after cladding burst in the hypothetical lossof coolant accident (LOCA) condition, we conductedoxidation tests in high temperature (650-1,150 oC)
steam flow using thermobalance.
Figure 2 shows an example of the mass gain(oxidation) profile during oxidation tests at 1,150 oC
and cross section of the samples after 1,200 s of thetests. Oxidation on the Cr-coated outer surface wassuppressed and macroscopic mass gain was halved
compared to the bare sample.
This result indicates that Cr coating on the Zr alloy
cladding outer surface may suppress the oxidation in
the accidental condition, and would be beneficial toenhance the accident tolerance of the cladding in thistemperature range, even after burst of the cladding.
*The samples were provided by Mitsubishi Nuclear
Fuel Co., Ltd.

Fission product behavior

Radioactive cesium (Cs) is one of the principal
radiation sources and information on the Cs
distribution within reactor pressure vessel (RPV) is of
crucial importance to make a reasonable safetyassessment for the fuel debris retrieval and thereactor decommissioning at 1F. Especially, a large
amount of Cs can be present in the upper region of
the RPV owing to chemical reactions of Cs vapor
species with structures, known as chemisorption.
Thus, a chemisorption model is incorporated intocurrent SA analysis codes. However, the existingchemisorption models cannot accurately reproduce
experimental results. Then, an improved model called
ECUME model was constructed by clarifying effects ofchemically affecting elements (i.e., silicon content in
stainless steel and gaseous Cs concentration).
Furthermore, ECUME (Effective Chemistry database offission products Under Multiphase rEaction) model
was incorporated into SA analysis code, SAMPSON(Severe Accident analysis code with Mechanistic,
Parallelized Simulations Oriented towards Nuclear
Fields), which is developed under the collaboration
with the Institute of Applied Energy (IAE), and theexperiment in the TeRRa (Test bench for FP Releaseand tRansport) facility with the temperature gradienttube to simulate SA conditions such as temperature
decrease and aerosol formation was analyzed.
Consequently, the SAMPSON with ECUME model
successfully reproduced the experimental results(Fig.1). This result indicates that ECUME model andthe analytical method such as models of aerosol
formation and the calculation method of saturated
CsOH vapor pressure can be applicable to the analysis
of Cs chemisorption behavior. From these results, theamount of chemisorbed Cs can be estimatedaccording to the SA analysis conditions.

Fig.1

Comparison of experimental andcalculated masses of chemisorbed Cs

Fig.2 Oxidation profiles during the test, and crosssection of the samples after the tests

Reference
1) H. Karasawa, et al., 2021 Fall Meeting of AESJ 3E03 (2021)(in Japanese).
2) Y. Nemoto, et al., 2022 Annual Meeting of AESJ, 2J05
(2022) (in Japanese).

Accident Tolerant Fuel (ATF)

For improvement of safety of the conventional LWRs,
we are conducting fundamental studies on ATF
cladding candidates to promote the developments inindustries. Chromium (Cr)-coated zirconium (Zr) alloy
cladding for PWR is one of the major ATF cladding
concepts. In this research, bare cladding and Cr-

Contact (Group Leader):NEMOTO Yoshiyuki
nemoto.yoshiyuki@jaea.go.jp

18

FY2021 NSEC Group Activity

Research Group for RadiochemistryRadiochemistry provides fundamental information
about the essential materials in developing nuclear
technology by identification of the chemical
reaction of radioactive materials. We chemicallyresolve various issues arisen from the nuclear
industry by developing new technique of
measurement and computational method. The
following two topics are our remarkableachievements of 2021.

release of radioisotopes is predicted to proceed via
interaction of groundwater with spent fuelresulting in dissolution. The dissolution will dependon the nature of the spent fuel surface, waterchemistry of the groundwater, and oxidants
generated by radiolysis. In this study, thedissolution of an oxidised form of uranium, U3O8, in
bicarbonate solution upon H2O2 addition wasinvestigated.
The dissolution of U was found to increase withbicarbonate concentration (Fig.2)2). This was
attributed to an increase in the oxidative
decomposition of H2O2 at the U3O8 surface, where
the oxidation reaction U(V) → U(VI) + e- is driven by
the reduction of H2O2. The oxidation reaction
destabilises the U3O8 lattice leading to dissolution:
U3O8 + H2O2 → 3UO22+(aq). As bicarbonate forms
stable complexes with U(VI), increasing thebicarbonate concentration drives the dissolution of
U3O8.
The 2nd topic was performed as part of "Project on
Research and Development of Spent Fuel Direct
Disposal as an Alternative Disposal Option (2020FY)”
under the contract with Ministry of Economy, Tradeand Industry (METI) (Grant Number: JPJ007597).

Solvent Extraction Mechanism ofLanthanide Ions
The transport mechanism of metal ions through theliquid–liquid oil/water interface in solvent
extractions remains unclear. Since the transport ofmetal ions between the oil and aqueous phases isclosely related to the extraction kinetics, theunderstanding of the transport mechanism ofmetal ions can contribute to the improvement of
the solvent extraction process. In our recent study1),
the adsorption process of trivalent lanthanide ionsfrom the aqueous phase to the interface in thesolvent
extraction
withthedi-(2ethylhexyl)phosphoric acid (HDEHP) extractant wasinvestigated through a model interface: water
surface covered with HDEHP (air/HDEHP/aqueousinterface) by using vibrational sum frequency
generation (VSFG) spectroscopy. The symmetric
POO– stretch vibrational signals of HDEHP at theinterface observed by VSFG spectroscopy anddensity functional theory (DFT) calculations
demonstrated that 1:1 lanthanide-HDEHP
complexes were formed at the air/HDEHP/aqueousinterface. The formation of the interfacial complex
could be an elementary chemical process occurring
just before the transfer of lanthanide ions to theside of the organic phase (Fig.1).

Fig.2 The relationship between the oxidative
decomposition of H2O2 on U3O8 and thedissolution of U into bicarbonate solution.
* Reproduced from Ref.2 with permission fromthe Royal Society of Chemistry.

Reference
1) R. Kusaka, et al., J. Phys. Chem. B 125(24), 6727 (2021).
2) J. McGrady, et al., RSC Adv. 11(46), 28940 (2021).

Fig.1 Proposed extraction mechanism of lanthanide
ions by di-(2-ethylhexyl)phosphoric acid
(HDEHP) extractant.

Contact (Group Leader):WATANABE Masayuki

Dissolution of U3O8 in Bicarbonate
Solution with H2O2 Addition

watanabe.masayuki@jaea.go.jp

In the event of nuclear waste canister failure, the19

FY2021 NSEC Group Activity

Research Group for Analytical Chemistry
Accurate analyses of radioactive substances arefundamental technologies supporting nuclear
science. We are developing practical analyticalmethods for radionuclides based on studies of
elucidation of chemical reactions and separation
phenomena such as adsorption, precipitation,
aggregation, etc. The separation techniques werealso applied to the development of radioactive
isotope isolation for alpha therapy. In thedecommissioning of the TEPCO’s Fukushima Daiichi
Nuclear Power Station (1F), our micro-analysis
technique was applied to elucidation of forms ofparticulate alpha emitter in a stagnant water in 1F.

centrifugation (Fig.2). The Pd recovery from thesimulated HLLW solution reached up to 50 %, while
99.5 % of the other 13 elements were separated.
The Pd precipitate could be separated fromradioactive elements (Sr, Cs, and Ba) and theinterfering elements for the ICP-MS determinationof 107Pd (Zr and Ru). These results show theapplicability of the proposed separation techniqueto HLLW samples.

Design of a Resin-packed MicroChannel for Uranium Separation
To reduce the radiation exposure risk andproduction of secondary radioactive wastes during
uranium (U) quantification, we are studying scaleddown separation method using a microchip.
Microchannels were designed to densely pack withresins, and effect of channel shape was examined1).
An ideal separation performance could be obtainedby arranging more than approx. 10 resins along thedepth and width of the microchannels as shown in
Fig.1. Then, the separation performance of the
microchannel for the seawater standard added 431
ppb Cs-133 (simulated 1F retained water) was
evaluated. The measured value of U in the seawater
sample was in good agreement with the certified
value. It indicates that the microchip column issufficiently practical. The size of the separation site
was scaled down to <1/5000 compared tocommonly used counterparts. The radiation
exposure risk and secondary radioactive wastes canbe reduced to 1/10 and 1/800, respectively, using aresin-packed microchannel.

Fig.1 Diagrams of resin-packed microchannels
with an ideal separation performance.

Fig.2 Formation of Pd precipitate by Xe lamp
irradiation.

Selective Pd Separation from
Simulated Radioactive Liquid
Waste by Precipitation using
Xenon Lamp Irradiation

Reference
1) K. Ouchi, et al., Anal. Sci. 37(12), 1789 (2021).
2) T. Yomogida, et al., Anal. Sci. 37(12), 1843 (2021).

Inventory estimation of 107Pd, which is one of thelong-lived fission products in high-level radioactive
liquid waste (HLLW) is indispensable for the longterm safety assessment of geological repository.
We have developed a simple and one-step Pd
separation technique based on photoreduction
with Xe lamp irradiation for the determination ofradioactive 107Pd in highly radioactive samples2). A
simulated HLLW solution was used to evaluate theseparation performance. The Pd precipitate wasformed by Xe lamp irradiation and recovered byContact (Group Leader):KITATSUJI Yoshihiro
kitatsuji.yoshihiro@jaea.go.jp20

FY2021 NSEC Group Activity

Research Group for Environmental Sciences
year after the accident. In terms of the 137Cs
adsorption on the seabed sediments, there was adifference among particle size classes, where clay
was the most effective in adsorption. The study alsosuggested that the seabed sediments were a
probable source releasing 137Cs into the seawater
after several months since the accident.
We will further improve the oceanic dispersion
model developed in this study. We should continue
the environmental assessment of radionuclides
caused by the accident by utilizing this model in the
future.

We research the dynamics of radionuclide transfer
in the atmospheric, terrestrial, and oceanic
environments to improve assessment technology
of environmental impact of radionuclides.
Computer models are developed and validated to
predict radionuclide transfer in the environments.
In particular, we develop the atmosphericprediction systems (WSPEEDI-II and WSPEEDI-DB)
and an oceanic prediction system (STEAMER). We
also conduct field survey to obtain environmental
data, and analyze the data with advanced
technology. The data is utilized to understand the
dynamics of radionuclide transfer and to validate
computer models.

Simulation on the dispersion andsedimentation of radionuclides in
the ocean off Fukushima
We developed a sophisticated oceanic dispersion
model considering interactions of radionuclides inseawater with multiscale suspended particles andseabed sediments1).
Oceanic dispersion hindcast was conducted byadoptingadouble-nested
downscaling
configuration for high resolution calculation in the
coastal ocean2) to validate the model’s accuracies
and analyze the 137Cs transfer caused by the
TEPCO’s Fukushima Daiichi Nuclear Power Plant(FNPP1) accident. The direct release of 137Cs into
the ocean was imposed in the model based on 137Cs
measurement data in the seawater. In addition, theatmospheric 137Cs deposition was also incorporated
into the sea surface, which was calculated by
WSPEEDI-II. Three size classes (sand, silt, and clay)
were considered as suspended particles andseabed sediments.
Comparison between model and observation
demonstrated that oceanic structure and the 137Csconcentrations in seawater and seabed sediments
were appropriately reproduced in the coastal ocean
off Fukushima. The study suggested that 137Cs was
mainly distributed along the coastal bottom
bathymetry (Fig.1). Shear stress effecting theresuspension of the seabed sediments was mainly
generated by waves in the nearshore area and byocean currents in the offshore area. The 137Cs
distribution in the seabed sediment off Fukushima
was mainly formed due to adsorption from thedissolved phase over several months since theaccident when the direct release of 137Cs was
remarkable. On the other hand, 137Cs transfer fromthe suspended phase resulted in a small effect on
the distribution in the seabed sediment of 137Cs one

Fig.1 Simulated annual mean 137Cs concentrationin the seabed sediments one year after the
FNPP1 accident. Dotted lines indicate thedepth of bottom bathymetry.
Reference
1) Y. Kamidaira, et al., J. Environ. Radioactivity 238-239,
106724 (2021).
2) Y. Kamidaira, et al., J. Geophys. Res.: Oceans 123(4), 2808
(2018).

Contact (Group Leader):KAWAMURA Hideyuki
kawamura.hideyuki@jaea.go.jp

21

FY2021 NSEC Group Activity

Research Group for Radiation Transport Analysis
Nowadays, computer simulation techniques that
can analyze radiation transport in materials are
essential tools for research and development in thefield of nuclear and radiation sciences. We havedeveloped a radiation transport simulation code,
the Particle and Heavy Ion Transport code System(PHITS), and applied it to industrial, scientific, andmedical studies. PHITS has been upgraded to
improve its higher reliability and to extend its area
to be applied. In addition, we also conduct studies
on radiological protection and radiation effects.
This paper presents our progresses in FY2021:
upgrades of PHITS and the development of aradiation dose estimation system for public
exposure.

The users can exactly reproduce the data of the
EXFOR in radiation transport analyses by PHITS.

RT-PHITS(User support function - -version - )RT-PHITS (RadioTherapy
package based on PHITS)
has been developed
under the support of the
National Institutes for
Quantum Science andTechnology(QST).
DICOM (Digital Imaging
and Communications in
Medicine) data, such as
PET-Image and CTImage, can be converted
to an input file for thedose calculation by RT- Fig.1 Interactive setting
PHITS. We have newly through GUI in RT-PHITS
introduced a -versionof Python Tkinter GUI. The users can interactively
define a condition of radiation dose analysis
through the GUI, as depicted in Fig.1.

Upgrades of the PHITS CodeThe major upgraded features are as follows in thenewest version (v 3.27) that was released in FY 2021.
Please check the PHITS homepage1).

Generalized track structure mode
ITSART (Ion Track Structure calculation model for
Arbitrary Radiation and Targets) has been
implemented to simulate nano-scale transport ofprotons and arbitrary ions in arbitrary matter.

Radiation Dose Estimation System
for Public Exposure
In FY 2020, we analyzed the impact of body sizes onorgan doses due to external neutron irradiation byhuman models. After that, a radiation dose
database was prepared by the analyses. In FY 2021,
radiation dose estimation system was developed
based upon the radiation dose database for public
exposure. Effective dose can be rapidly obtained forneutron (1x10-9 MeV to 1x104 MeV) and photon(1x10-2 MeV to 2x101 MeV) exposures by taking
account for physique of adults, ages (6 age groups)
of infants or children and an irradiation geometry.

Treatment of nuclear data
We upgraded the treatment of nuclear data in thenewest version of PHITS.
 The memory for containing nuclear data ischanged from static to dynamic one so thatPHITS can read extremely large nuclear data
without increasing a parameter for total
memory usage of PHITS.
 Functions to read nuclear data libraries in the
A Compact Evaluated nuclear data file format(ACE format) are implemented for deuteron,alpha particle, and photon. Here, the datalibrary for deuteron, JENDL/DEU-2020 iscontained in PHITS. Deutron will be applied tointensive fast neutron sources using deuteronaccelerators.
 A new function is introduced to automaticallydetermine the maximum energy of nuclear
data library for each nucleus from an address
file. The users do not have to define themaximum energy for each nucleus and caneasily use high energy nuclear data libraries,
such as JENDL-4.0/HE.
 A new function (named as ‘Exfor2frag’) is
introduced to convert the experimental crosssection data in the EXFOR (Experimental
Nuclear Reaction Data) to a data file in PHITS.

Reference
1) PHITS homepage, https://phits.jaea.go.jp/ (accessed2022-11-08).

Contact (Group Leader):
TAKAHASHI Fumiaki
takahashi.fumiaki@jaea.go.jp

22

FY2021 NSEC Group Activity

Research Group for Partitioning
Partitioning and transmutation has been proposed
as a strategy for managing high-level radioactive
waste (HLW) generated by reprocessing of spent
nuclear fuels via a hydrometallurgical method. HLW
consists of many elements with different
radiotoxicities and chemical properties, and thus itis reasonable to separate the elements into groups.
To this end, our research group has beendeveloping several extractants and proposed anovel hydrometallurgical process called SELECT(Solvent Extraction from Liquid waste using
Extractants of CHON-type for Transmutation) torecycle nuclear materials and separate actinides. A
conceptual flow sheet of SELECT is shown in Fig.1.
This process consists of the following four steps:(i) recovery of U and Pu from dissolution solution of
spent nuclear fuels by monoamides,(ii) recovery of Am, Cm, and rare earth elements(REs) from HLW by tetradodecyldiglycolamide(TDdDGA),(iii) separation of Am and Cm from REs by hexaoctyl
nitrilotriacetamide (HONTA), and(iv) separation of Am and Cm by alkyl diamide
amine (ADAAM).
The extractants used in this process consist ofcarbon, hydrogen, oxygen, and nitrogen, and thus
can be decomposed into gases by incineration. This
contributes to reducing the volume of secondary
solid waste.

TDdPTDA complex depended on the polarity of thediluents. Furthermore, TDdPTDA showed sufficient
separation performance not only in nitrobenzene
and F-3 but also in n-dodecane. This property also
supports the practicality of TDdPTDA in thatcommercially operating reprocessing plants haveused aliphatic hydrocarbons such as n-dodecane.
The studies on PTDAs are ongoing, and we will
synthesize novel PTDAs with different side chains,
investigate the extraction properties, and evaluate
the separation performance to enhance the SELECT
process.

Fig.1 Conceptual flow sheet of SELECT process

Studies on a Novel Extractant,
TDdPTDA
Although the former studies showed theapplicability of the extractants used in the current
SELECT process, we have been developing novel
extractants for further improvement in the process.
We focused on phenanthroline diamides (PTDAs) as
alternative extractants to HONTA for the separationof REs from Am and Cm, and single-stage batch
experiments were carried out using TDdPTDA(Fig.2) which is one of PTDAs1,2).
According to the time dependencies of Am, Cm,
and Eu extraction, the extraction reaction reachedequilibrium within 30 seconds indicating that theextraction rate of TDdPTDA exhibited was fastehough for practical use rather than that of HONTA,
and this leads to improvement of the separation
process. Effects of diluents such as 3nitrobenzotrifluorite (F-3), nitrobenzene, and ndodecane on the extraction behavior of Am, Cm,and lanthanides were evaluated with various
concentrations of TDdPTDA and nitric acid. The
results indicated that the structure of metal-

Fig.2 Structure of N,N,N',N'-tetradodecyl-1,10phenanthroline-2,9-dicarboxamide (TDdPTDA)
Reference
1) N. Tsutsui, et al., Anal. Sci. 36(2), 241 (2020).
2) N. Tsutsui, Doctoral Dissertations (Tokyo Institute of Tech.)(2022).

Contact (Group Leader):BAN Yasutoshi
ban.yasutoshi@jaea.go.jp

23

FY2021 NSEC Group Activity

Research Group for Nuclear Transmutation System
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 embodying the upper radiation shielddesign and the subcriticality monitoring system.

Subcriticality monitoring
We have proposed a safe and efficientmethodology to make the ADS approach a target
subcriticality during fuel loading2). In thismethodology, we need to perform the pulse
neutron source (PNS) measurement for theabsolute value of the subcriticality (Fig.2) at theinitial state to give a calibration point for
subsequent subciriticality monitoring.
As a feasibility study, we have explored practicalparameters of the accelerator with 1.5 GeV protons
for the PNS measurement. Considering
uncertainties derived from the dead-time, thestatistical error and the practical measurement
time (<10 h), we have deduced accelerator
parameters with which the measurement
uncertainty satisfies a given upper error bound(=2%): 200 Hz of pulse repetition with 10 µs of pulse
width and 3 mA of peak current.

Radiation shielding design
Since the ADS core is connected with beamtransport equipment via a beam duct andbackscattering of high-energy particles becomes asignificant issue, the design of ADS upper structure
requires a detailed assessment of radiation doses
around the beam duct and radioactivity of theequipment for radiation protection. We haveanalyzed them using the Monte Carlo transport
code system PHITS and proposed the upper
structure of ADS1). Figure 1 illustrates the proposed
structure with the upper shield to reducebackscattered neutron, the neutron dump toreceive high energy neutron and the additionalshield to mitigate neutron and gamma ray in upperarea. This structure enables to reduce the radiationdose to sufficiently low level at the site boundary of
ADS.

Fig.2 Schematic view of PNS measurement
Reference
1) H. Iwamoto, et al., JAEA-Res. 2021-012 (2022) (inJapanese).
2) T. Okamura, K. Nishihara, et al., JAEA-Data/Code 2021016 (2022) (in Japanese).

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

Fig.1 Proposed design of ADS upper structure24

FY2021 NSEC Group Activity

Research Group for MA Transmutation Fuel Cycle
formed in ZrN-based MA transmutation nitride
fuels. In our future work, stability of suchintermetallic compounds will be clarified todevelop the technology for reprocessing the MA
transmutation nitride fuels.

Since the ratio of minor actinides (MAs) which canbe transmuted in the accelerator-driven system(ADS) core is limited, residual MAs in the spenttransmutation fuels should be separated andreused to transmute MAs effectively. Therefore, wehave been carrying out research and developmentof the technology for reprocessing MA
transmutation fuels. Regarding U-free inert matrix
MA nitride fuels, studies on pyrochemical
reprocessing and nitridation of recovered
transuranium elements (TRU: MAs and Pu) havebeen carried out.

Fission product (FP) compounds inthe spent MA nitride fuels
Recovery yield of MAs should be high to minimize
the amounts of MAs in the radioactive waste which
is discharged by reprocessing MA transmutation
fuels1). Target recovery yield is 99.9 % to transmute
99 % of MAs received into the transmutation fuelcycle1). To develop the technology for reprocessing
the spent fuels, stability of the FP compounds
formed in the fuels should be considered.
In UN and (U,Pu)N fuels, platinum group metals(PGMs: Ru, Rh, Pd) tend to precipitate out as theintermetallic
compounds
suchas(U,Pu)(Ru,Rh,Pd)32). Molten salt electrorefining
experiments using burnup-simulated UN samples
showed that thermodynamically stable UPd3 was
not dissolved at the anode3). To treat such anoderesidues, we have proposed a chlorination method
using CdCl2. This method was proved to be effective
for surrogates of TRUPd3 (e.g., GdPd3) and NpPd34).
Solid solution type ZrN-based nitride fuel,(TRU,Zr)N has been chosen as the first candidate for
MA transmutation fuel for ADS in JAEA1). But eventhe chemical compounds formed by the reaction of(TRU,Zr)N with PGMs have not been studied.
Therefore, chemical reaction behavior of (Gd,Zr)N
with PGMs have been investigated regarding Gd as
a surrogate of TRU. The mixture of Gd0.25Zr0.75N and
Pd (molar ratio 4:3.1) heated at 1,323 K in Ar gas
atmosphere was analyzed5). The X-ray diffraction(XRD) profile showed the existence of a phasewhich was isostructural to cubic GdPd3 and its
lattice constant was smaller than that of GdPd3(Fig.1)5). The difference should be due to thesubstitution of Zr atoms for Gd atoms to form
(Gd,Zr)Pd3. Figure 2 shows a SEM image of thesample; (Gd,Zr)Pd3 phase was identified by EDS
analyses as well5). Based on the results, wepresume that compounds like (TRU,Zr)Pd3 can be

Fig.1 XRD profiles of the samples

Fig.2 SEM image of Gd0.25Zr0.75N+Pd sample
after the reaction

Reference
1) H.Tateno, T. Sato, et al., J. Nucl. Sci. Tech. 57(3), 224 (2020).
2) Y. Arai, “3.02 Nitride Fuel” in Comprehensive Nucl. Mater.
Vol.3 (Elsevier), 41 (2012).
3) T. Satoh, et al., J. Nucl. Sci. Tech. 46(6), 557 (2009).
4) H. Hayashi, et al., 2021 Annual Meeting of AESJ 3H13
(2021) (in Japanese).
5) R. Mishima, et al., 2022 Annual Meeting of AESJ 2I11
(2022) (in Japanese).

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

FY2021 NSEC Publications

Publication list
* Works with underlined numbers were published before
FY2021 (not included in the lists of previous NSEC reports).

Nuclear and LWR Engineering Division
Nuclear Data Center
Papers‐delayed neutron‐emission and fission
calculations within relativistic quasiparticle
random‐phase approximation and a statisticalmodel, F. Minato, T. Marketin & N. Paar, Phys. Rev.
C 104(4), 044321 (2021).
2) Theoretical Study of Deuteron‐Induced
Reactions in the Nuclear Data Field, S. Nakayama,
O. Iwamoto, Y. Watanabe & K. Ogata, Few‐Body
Systems 63, 4 (2022).
3) Neutron capture and total cross‐section
measurements and resonance parameter
analysis of niobium‐93 below 400 eV, S. Endo, A.
Kimura, S. Nakamura, O. Iwamoto, N. Iwamoto,G. Rovira, K. Terada, S.‐i. Meigo, Y. Toh, M.
Segawa, M. Maeda & M. Tsuneyama, J. Nucl. Sci.
Tech. 59(3), 318 (2022).
4) Thermal‐neutron capture cross‐section
measurement of Tantalum‐181 using graphite
thermal column at KUR, S. Nakamura, Y.
Shibahara, S. Endo & A. Kimura, J. Nucl. Sci. Tech.
58(10), 1061 (2021).
5) Integral experiments of technetium‐99 using
fast‐neutron source reactor ‘YAYOI’, S. Nakamura,
Y. Hatsukawa, A. Kimura, Y. Toh & H. Harada, J.
Nucl. Sci. Tech. 58(12), 1318 (2021).
6) Integral experiment of 129I(n, γ) reaction using
fast neutron source in the ‘YAYOI’ reactor, S.
Nakamura, Y. Toh, A. Kimura, Y. Hatsukawa & H.
Harada, J. Nucl. Sci. Tech. 59(7), 851 (2022).
7) Neutron beam filter system for fast neutron
cross‐section measurement at the ANNRI
beamline of MLF/J‐PARC, G. Rovira, A. Kimura, S.
Nakamura, S. Endo, O. Iwamoto, N. Iwamoto, T.
Katabuchi, K. Terada, Y. Kodama, H. Nakano, J.‐i.
Hori & Y. Shibahara, Nucl. Inst. & Methods in Phys.
Res., A 1003, 165318 (2021).
8)
KeV‐neutron
capturecross‐section
measurement of Au‐197 with a Cr‐filteredneutron beam at the ANNRI beamline of MLF/J‐
PARC, G. Rovira, A. Kimura, S. Nakamura, S. Endo,
O. Iwamoto, N. Iwamoto, T. Katabuchi, Y. Kodama,

H. Nakano, Y. Sato, J.‐i. Hori, Y. Shibahara & K.
Terada, J. Nucl. Sci. Tech. 59(5), 647 (2022).
9) Calculation of recoil nucleus spectrum in thepresence of multi‐particle emission in nuclear
reaction with Monte Carlo method as anextension of CCONE code, O. Iwamoto, J. Nucl.
Sci. Tech. 59(10), 1232 (2022).
10) KeV‐region analysis of the neutron capture
cross‐section of Np‐237, G. Rovira, T. Katabuchi,
K. Tosaka, S. Matsuura, Y. Kodama, H. Nakano, O.
Iwamoto, A. Kimura, S. Nakamura & N. Iwamoto,J. Nucl. Sci. Tech. 59(1), 110 (2022).
11) Energy‐dependent angular distribution ofindividual γ rays in the 139La(n, γ) 140La∗ reaction,
T. Okudaira, S. Endo, H. Fujioka, K. Hirota, K.
Ishizaki, A. Kimura, M. Kitaguchi, J. Koga, Y.
Niinomi, K. Sakai, T. Shima, H.M. Shimizu, S.
Takada, Y. Tani, T. Yamamoto, H. Yoshikawa & T.
Yoshioka, Phys. Rev. C 104(1), 014601 (2021).
12) G‐HyND: a hybrid nuclear data estimator with
Gaussian processes, H. Iwamoto, O. Iwamoto &S. Kunieda, J. Nucl. Sci. Tech. 59(3), 334 (2022).
13) Benchmark study of particle and heavy‐ion
transport code system using shielding integral
benchmark archive and database for accelerator‐
shielding experiments, Y. Iwamoto, S. Hashimoto,T. Sato, N. Matsuda, S. Kunieda, Y. Çelik, N.
Furutachi & K. Niita, J. Nucl. Sci. Tech. 59(5), 665(2022).
14) Isomer production ratio of the 112Cd(n, γ) 113Cd
reaction in an s‐process branching point, T.
Hayakawa, Y. Toh, A. Kimura, S. Nakamura, T.
Shizuma, N. Iwamoto, S. Chiba & T. Kajino, Phys.
Rev. C 103(4), 045801 (2021).
15) Large scale production of Cu‐64 and Cu‐67 via
the 64Zn(n, p)64Cu and 68Zn(n, np/d)67Cu
reactions using accelerator neutrons, M.
Kawabata, S. Motoishi, A. Ohta, A. Motomura, H.
Saeki, K. Tsukada, S. Hashimoto, N. Iwamoto, Y.
Nagai & K. Hashimoto, J. Radioanal. Nucl. Chem.
330(3), 913 (2021).

1)

26

FY2021 NSEC Publications16) Measurements of the neutron capture crosssection of Am‐243 around 23.5 keV, Y. Kodama, T.
Katabuchi, G. Rovira, A. Kimura, S. Nakamura, S.
Endo, N. Iwamoto, O. Iwamoto, J.‐i. Hori, Y.
Shibahara, K. Terada, H. Nakano & Y. Sato, J. Nucl.
Sci. Tech. 58(11), 1159 (2021).
17) Nondestructive Quantitative Analysis ofDifficult‐to‐Measure Radionuclides Pd‐107 andTc‐99, Y. Toh, M. Segawa, M. Maeda, M.
Tsuneyama, A. Kimura, S. Nakamura, S. Endo &M. Ebihara, Anal. Chem. 93(28), 9771 (2021).
18) Investigation of radioactive samples forneutron capture reaction measurements using
energy‐resolved neutron imaging, M. Segawa,Y.Toh, T. Kai, A. Kimura & S. Nakamura, Annals
Nucl. Energy 167, 108828 (2022).
19) Measurement of the 72Ge(n, γ) cross section
over a wide neutron energy range at the CERN
n_TOF facility, M. Dietz, et al. (The n_TOF
Collaboration (H. Harada & A. Kimura)), Phys. Rev.
C 103(4), 045809 (2021).
20) Measurement of the 76Ge(n, γ) cross section at
the n_TOF facility at CERN, A. Gawlik‐Ramięga, etal. (The n_TOF Collaboration (H. Harada & A.
Kimura)), Phys. Rev. C 104(4), 044610 (2021).
21) Constraints on the dipole photon strength forthe odd uranium isotopes, J. Moreno‐Soto, et al.
(The n_TOF Collaboration (A. Kimura)), Phys. Rev.

C 105(2), 024618 (2022).
22) Estimated Isotopic Compositions of Yb in
Enriched Yb‐176 for Producing Lu‐177 with HighRadionuclide Purity by 176Yb(d,x)177Lu, Y. Nagai,
M. Kawabata, S. Hashimoto, K. Tsukada, K.
Hashimoto, S. Motoishi, H. Saeki, A. Motomura,
F. Minato & M. Itoh, J. Phys. Soc. Jpn. 91, 044201(2022).
23) CO2‐2 Thermal‐Neutron Capture Cross‐Section
Measurement of Np‐237 Using Graphite Thermal
Column, S. Nakamura, S. Endo, A. Kimura & Y.
Shibahara, KURNS PROGRESS REPORT 2020, 94(2021).
24) Extraction test of stopped Bi isotopes in PALIS
gas cell, T. Sonoda, I. Katayama, M. Wada, H.
Ishiyama, V. Sonnenschein, H. Tomita, R.
Terabayashi, K. Hattori, H. Iimura, S. Iimura, T.M.
Kojima, M. Rosenbusch, A. Takamine, N. Fukuda,
T. Kubo, S. Nishimura, Y. Shimizu, T. Sumikawa, H.
Suzuki, H. Takeda, M. Tanigaki & K. Yoshida,
RIKEN Accel. Prog. Rep. 54, 91 (2021).
25) Improvement of evacuation time of RI fromargon gas cell, T. Sonoda, M. Wada, K. Hattori, H.
Iimura, S. Iimura, H. Ishiyama, T.M. Kojima, M.
Rosenbusch, V. Sonnenschein, R. Terabayashi, A.
Takamine & H. Tomita, RIKEN Accel. Prog. Rep. 54,
92 (2021).

Research Group for Reactor Physics and Standard Nuclear Code System
Papers1) Improvements in Computational Efficiency for
Resonance Calculation Using Energy Spectrum
Expansion Method, R. Kondo, T. Endo, A.
Yamamoto, S. Takeda, H. Koike, K. Yamaji & K.
Asano, Nucl. Sci. Eng. 196(7), 769 (2022).
2) Adaptive setting of background cross sections forgeneration of effective multi‐group crosssections in FRENDY nuclear data processing code,
A. Yamamoto, T. Endo & K. Tada, J. Nucl. Sci. Tech.
58(12), 1343 (2021).
3) Problems on neutron production data of Be‐9 in
TENDL‐2017 and ‐2019 deuteron sub‐libraries, S.
Kwon, C. Konno, M. Ohta & S. Sato, Annals Nucl.
Energy 169, 108932 (2022).
4) Benchmark study of particle and heavy‐ion
transport code system using shielding integral
benchmark archive and database for accelerator‐

shielding experiments, Y. Iwamoto, S. Hashimoto,T. Sato, N. Matsuda, S. Kunieda, Y. Çelik, N.
Furutachi & K. Niita, J. Nucl. Sci. Tech. 59(5), 665(2022).
5) Adjoint‐weighted correlated sampling for k‐eigenvalue perturbation in Monte Carlocalculation, D. Tuya & Y. Nagaya, Annals Nucl.
Energy 169, 108919 (2022).
6) Nuclear data processing code FRENDY: A
verification with HTTR criticality benchmark
experiments, N. Fujimoto, K. Tada, H.Q. Ho, S.
Hamamoto, S. Nagasumi & E. Ishitsuka, Annals
Nucl. Energy 158, 108270 (2021).
7) Multi‐group neutron cross section generation
capability for FRENDY nuclear data processing
code, A. Yamamoto, K. Tada, G. Chiba & T. Endo,
J. Nucl. Sci. Tech. 58(11), 1165 (2021).

JAEA Report
1) Carrying‐out of whole nuclear fuel materials in

Plutonium Research Building No.1, J. Inagawa, Y.

27

FY2021 NSEC Publications
Tachihara, T. Kida & M. Watanabe, JAEA‐Tec.
2021‐001 (2021) (in Japanese).

Kitatsuji, H. Otobe, M. Nakada M. Takano, H. Akie,
O. Shimizu, M. Komuro, H. Ohura, I. Nagai, K.
Harada, K. Suzuki, R. Morita, J. Ishikawa, O.

Research Group for Nuclear Sensing
Papers1) First demonstration experiment of the neutron
rotation method for detecting nuclear material,
M. Komeda, Y. Toh, K. Tanabe, Y. Kitamura & T.
Misawa, Annals Nucl. Energy 159, 108300 (2021).
2) Nondestructive Quantitative Analysis of Difficult‐to‐Measure Radionuclides Pd‐107 and Tc‐99, Y.
Toh, M. Segawa, M. Maeda, M. Tsuneyama, A.
Kimura, S. Nakamura, S. Endo & M. Ebihara, Anal.
Chem. 93(28), 9771 (2021).
3) Investigation of radioactive samples for neutron
capture reaction measurements using energy‐
resolved neutron imaging, M. Segawa, Y. Toh, T.
Kai, A. Kimura & S. Nakamura, Annals Nucl.
Energy 167, 108828 (2022).
4) Isomer production ratio of the 112Cd(n,)113Cd
reaction in an s‐process branching point, T.
Hayakawa, Y. Toh, A. Kimura, S. Nakamura, T.
Shizuma, N. Iwamoto, S. Chiba & T. Kajino, Phys.
Rev. C 103(4), 045801 (2021).
5) Neutron capture and total cross‐section
measurements and resonance parameter
analysis of niobium‐93 below 400 eV, S. Endo, A.
Kimura, S. Nakamura, O. Iwamoto, N. Iwamoto,G. Rovira, K. Terada, S.‐i. Meigo, Y. Toh, M.
Segawa, M. Maeda & M. Tsuneyama, J. Nucl. Sci.
Tech. 59(3), 318 (2022).
6) Integral experiments of technetium‐99 using
fast‐neutron source reactor ‘YAYOI’, S. Nakamura,
Y. Hatsukawa, A. Kimura, Y. Toh & H. Harada, J.
Nucl. Sci. Tech. 58(12), 1318 (2021).
7) Integral experiment of 129I(n, γ) reaction using
fast neutron source in the ‘YAYOI’ reactor, S.
Nakamura, Y. Toh, A. Kimura, Y. Hatsukawa & H.
Harada, J. Nucl. Sci. Tech. 59(7), 851 (2022).
8) Meteorological Aspects of Gamma‐Ray Glows in
Winter Thunderstorms, Y. Wada, T. Enoto, M.
Kubo, K. Nakazawa, T. Shinoda, D. Yonetoku, T.
Sawano, T. Yuasa, T. Ushio, Y. Sato, G.S. Diniz & H.
Tsuchiya,
Geophys.
Res.
Lett.
48(7),

e2020GL091910 (2021).
Characteristics of Low‐Frequency Pulses
Associated With Downward Terrestrial Gamma‐
Ray Flashes, Y. Wada, T. Morimoto, Y. Nakamura,
T. Wu, T. Enoto, K. Nakazawa, T. Ushio, T. Yuasa &H. Tsuchiya, Geophys. Res. Lett. 49(5),e2021GL097348 (2022).
10) Multiple Gamma‐Ray Glows and a Downward
TGF Observed From Nearby Thunderclouds, S.
Hisadomi, K. Nakazawa, Y. Wada, Y. Tsuji, T. Enoto,
T. Shinoda, T. Morimoto, Y. Nakamura, T. Yuasa &H. Tsuchiya, JGR Atmospheres 126(18),e2021JD034543 (2021).
11) Catalog of gamma‐ray glows during four winterseasons in Japan, Y. Wada, T. Matsumoto, T.
Enoto, K. Nakazawa, T. Yuasa, Y. Furuta, D.
Yonetoku, T. Sawano, G. Okada, H. Nanto, S.
Hisadomi, Y. Tsuji, G. S. Diniz, K. Makishima & H.
Tsuchiya, Phys. Rev. Res. 3(4), 043117 (2021).
12) High sensitivity determination of iridium
contents in ultra‐basic rocks by INAA withcoincidence gamma‐ray detection, M. Ebihara, N.
Shirai, J. Kuwayama & Y. Toh, Nucl. Eng. Tech.
54(2), 423 (2022).
13) Development of An Integrated Active Neutron
Non‐Destructive Analysis System: Active‐N, Y.
Toh, A. Ohzu, H. Tsuchiya, K. Furutaka, F. Kitatani,
M. Komeda, M. Maeda & M. Koizumi, Proc. theINMM & ESARDA Joint Annual Meeting (2021).
14) The design and implementation of the PGA
measurement system in an integrated Active
Neutron non‐destructive analysis system,“Active‐N”, K. Furutaka, A. Ohzu & Y. Toh, Proc.
the INMM & ESARDA Joint Annual Meeting(2021).
15) CO8‐1 Developments for an innovative method
to detect nuclear materials, M. Komeda, Y. Toh, Y.
Kitamura, T. Misawa & K. Tanabe, KURNSPROGRESS REPORT 2020, 199 (2021).
9)

PatentJapanese Patent(2021.10.22)

1) Segawa M., Maeda M. & Toh Y., “Method andapparatus for analysis of radioactive isotopes”,

28

Application

2021‐173289

FY2021 NSEC Publications

Development Group for Thermal‐Hydraulics Technology
Papers1) NUMERICAL SIMULATION OF TWO‐PHASE FLOWIN THE FUEL ASSEMBLIES WITH THE SPACER
GRID, A. Ono, S. Yamashita, T. Suzuki & H. Yoshida,
Proc. NURETH‐19 (19th International Topical
Meeting on Nuclear Reactor Thermal Hydraulics)(2022).
2) DEVELOPMENT OF DISPERSED PHASE TRACKINGMETHOD FOR TIME‐SERIES 3‐DIMENSIONALINTERFACE SHAPE DATA, N. Horiguchi, S.
Yamamura, K. Fujiwara, A. Kaneko, H. Yoshida &Y. Abe, Proc. NURETH‐19 (19th International
Topical Meeting on Nuclear Reactor Thermal
Hydraulics) (2022).
3) DEVELOPMENT OF NUMERICAL SIMULATIONMETHOD FOR OXIDATION UNDER SEVERE
ACCIDENT CONDITIONS USING JUPITER, S.
Yamashita, T. Sato, Y. Nagae, M. Kurata & H.
Yoshida, Proc. NURETH‐19 (19th International
Topical Meeting on Nuclear Reactor Thermal
Hydraulics) (2022).
4)
EXPERIMENTALAND
NUMERICALINVESTIGATIONS OF SPLASHING DURING SINGLE
DROP IMPACT ONTO A LIQUID FILM, T. Okawa, K.
Kawai, K. Kubo, S. Yamashita & H. Yoshida, Proc.
NURETH‐19 (19th International Topical Meetingon Nuclear Reactor Thermal Hydraulics) (2022).
5) CFD ANALYSIS OF NATURAL CIRCULATION IN LBE‐
COOLED ACCELERATOR‐DRIVEN SYSTEM, T.
Sugawara, K. Ichihara, K. Hanzawa, K. Nishihara,
N. Watanabe & A. Ono, Proc. NURETH‐19 (19thInternational Topical Meeting on Nuclear
Reactor Thermal Hydraulics) (2022).
6) Toward mechanistic evaluation of Critical Heat
Flux in nuclear reactors (2) Recent studies andfuture challenges toward mechanistic andreliable CHF evaluation, Res. Committee for
Mechanistic Evaluation of CHF for Nuclear
Reactors, J. the Atomic Energy Soc. Jpn. 63(12),820 (2021).
7) Core Thermal‐Hydraulic Analysis During Dipped‐
Type Direct Heat Exchanger Operation in Natural
Circulation Conditions, E. Hamase, N. Doda, A.
Ono, Y. Miyake, Y. Imai & M. Tanaka, Proc.
ICONE28, ICONE28‐63380 (2021).
8) Measurement of Liquid Film Thickness forAnnular Two‐Phase HFC134a Gas‐Liquid Ethanol
Flow in the Vertical Tube, H. Zhang, T. Hisano, S.
Mori & H. Yoshida, Proc. ICONE28, ICONE28‐
63488 (2021).
9) Liquid Film Behavior of Bottoming Liquid Jet in a
Shallow Pool Measured by 3D‐LIF, S. Yamamura,
H. Yoshida, N. Horiguchi, A. Kaneko & Y. Abe, Proc.
ICONE28, ICONE28‐64733 (2021).
10) Iterative methods with mixed‐precisionpreconditioning for ill‐conditioned linear
systems in multiphase CFD simulations, T. Ina, Y.
Idomura, T. Imamura, S. Yamashita & N. Onodera,
Proc. 2021 12th WS on Latest Advances in
Scalable Algorithms for Large‐Scale Systems(ScalA) (2021).

Fuels and Materials Engineering Division
Research Group for Corrosion Resistant Materials
PapersRate of Carbon Steel in Air/solution Alternating
Condition, K. Otani, F. Ueno & C. Kato, 材料と環境 Zairyo‐to‐Kankyo 71(2), 40 (2022) (inJapanese).
4) Mechanism of Deoxidization Effect by Hydrazine
under Gamma‐ray Irradiated Condition, M.
Yamamoto, T. Motooka & T. Sato, 材料と環境
Zairyo‐to‐Kankyo 70(12), 392 (2021) (inJapanese).
5) Corrosion of Carbon Steel in the Simulated
Air/Solution Interface Environment, K. Otani & C.

1) Modeling and Simulation of Atmospheric
Corrosion of Carbon Steel Considering
Environmental Factor, T. Igarashi, A. Komatsu, C.
Kato & M. Sakairi, 鉄 と 鋼 Tetsu‐to‐Hagane
107(12), 998 (2021) (in Japanese).
2) Three‐dimensional Computational Modeling and
SimulationofIntergranularCorrosion
Propagation of Stainless Steel, T. Igarashi, A.
Komatsu, T. Motooka, F. Ueno & M. Yamamoto,
Corrosion Sci. Tech. 20(3), 105 (2021).
3) Effect of Oxygen Concentration on Corrosion

29

FY2021 NSEC Publications
Kato, 材 料 と 環 境 Zairyo‐to‐Kankyo 70(12),480 (2021) (in Japanese).
6) Effect of Gamma‐ray Irradiation on Corrosion of
Stainless Steel Contacted with Zeolite Particle, C.
Kato, I. Yamagishi, T. Sato & M. Yamamoto, 材料と環境 Zairyo‐to‐Kankyo 70(12), 441 (2021) (inJapanese).
7) Effect of Oxidants on Corrosion of Carbon Steelunder Irradiation Conditions, T. Sato, A. Komatsu,
J. Nakano & M. Yamamoto, 材料と環境 Zairyo‐
to‐Kankyo 70(12), 457 (2021) (in Japanese).
8) Development of atmospheric corrosion model
considering meteorological data and airborne
sea salt, T. Igarashi, A. Komatsu, C. Kato & M.
Sakairi, 防 錆 管 理 Rust prevention & control
65(10), 365 (2021) (in Japanese).
9) Time Dependence of Corrosion Behavior on Ta in
NaOH Solutions, Y. Ishijima, F. Ueno & H. Abe,
Mater. Trans. 63(4), 538 (2022).
10) Polarization Characteristics and Evaluation ofCorrosion Rate of Stainless Steel in Nitric Acid
Solution Containing Np‐237, E. Irisawa, C. Kato,

N. Yamashita & N. Sano, 材料と環境 Zairyo‐to‐Kankyo 71(3), 70 (2022) (in Japanese).
11) Positron Annihilation Lifetime Spectroscopy
Investigation of Thermal Aging Effect for the
Mechanical Properties of Hydrogen‐Absorbed
Tantalum, Y. Ishijima, K. Yokoyama, F. Ueno & H.
Abe, Mater. Trans. 63(4), 592 (2022).
12) Study on the free corrosion potential at aninterface between an Al electrode and an acidic
aqueous NaCl solution through density
functional theory combined with the reference
interaction site model, K. Kano, S. Hagiwara, T.
Igarashi & M. Otani, Electrochimica Acta 377,
138121 (2021).
13) Corrosion Monitoring of Carbon Steel in Non‐
Irradiated, Humidity‐Controlled Environments
Simulating Gamma‐Ray Irradiation, A. Omori, S.
Ajito, H. Abe, K. Hata, T. Sato, Y. Kaji, H. Inoue, M.
Taguchi, H. Seito, E. Tada, S. Suzuki & E. Akiyama,
材 料 と 環 境 Zairyo‐to‐Kankyo 70(11), 358(2021) (in Japanese).

Patent1) Otani K. & Kato C., “ANTI‐CORROSION AGENT
AND ANTI‐CORROSION METHOD IN WATERSYSTEM”, Japanese Patent 6932409 (2021.8.20)

Research Group for Radiation Materials Engineering
Papers1) Radiation damage mechanism in ceramics
irradiated with swift heavy ions, N. Ishikawa, T.
Taguchi & N. Okubo, し ょ う と つ J. Atomic
Collision Res. 18(3), 43 (2021) (in Japanese).
2) Geometries and electronic states of iron trimer(Fe3) by CCSD and CCSD(T) calculations, T.
Nakazawa, AIP Adv. 11(4), 045032 (2021).
3) Effect of Irradiation on Corrosion Behavior of
316L Steel in Lead‐Bismuth Eutectic withDifferent Oxygen Concentrations, N. Okubo, Y.
Fujimura & M. Tomobe, Quantum Beam Sci. 5(3),27 (2021).
4) Dislocation core structure and motion in puretitanium and titanium alloys: A first‐principles
study, T. Tsuru, M. Itakura, M. Yamaguchi, C.
Watanabe & H. Miura, Computational Mater. Sci.
203, 111081 (2022).
5) Synergetic effect of Si addition on mechanicalproperties in face‐centered‐cubic high entropy
alloys: a first‐principles study, T. Tsuru, I.
Lobzenko & D. Wei, Modelling & Simulation inMater. Sci. Eng. 30(2), 024003 (2022).
6) Vacancy migration in α‐iron investigated using insitu high‐voltage electron microscopy, Y. Abe, Y.
Satoh & N. Hashimoto, Philosophical Magazine
102(12), 1173 (2022).
7) Dislocation‐climbing bypass over dispersoids
with different lattice misfit in creep deformationof FeCrAl oxide dispersion‐strengthened alloys, S.
Ukai & S. Yamashita, J. Mater. Res. Tech. 16, 891(2022).
8) Temperature dependence of positronannihilation lifetime in near‐surface and bulk ofroom‐temperature ionic liquid observed by aslow positron beam, T. Hirade, K. Michishio, Y.
Kobayashi & N. Oshima, Chem. Phys. Lett. 795,
139507 (2022).
9) Migration energy of a self‐interstitial atom in α‐iron estimated by in situ observation ofinterstitial clusters at low temperatures using
high‐voltage electron microscopy, Y. Abe, Y.
Satoh & N. Hashimoto, Philosophical Magazine30

FY2021 NSEC Publications
101(14), 1619 (2021).
10) Development of accident tolerant FeCrAl‐ODS
fuel cladding for BWRs in Japan, K. Sakamoto, Y.
Miura, S. Ukai, N.H. Oono, A. Kimura, A. Yamaji,
K. Kusagaya, S. Takano, T. Kondo, T. Ikegawa, I.
Ioka & S. Yamashita, J. Nucl. Mater. 557, 153276(2021).
11) Orientation dependence of yield strength in a
new single crystal‐like FeCrAl oxide dispersion
strengthened alloy, S.M.S. Aghamiri, T. Sugawara,
S. Ukai, N. Oono, K. Sakamoto & S. Yamashita,
Mater. Characterization 176, 111043 (2021).
12) Effects of Helium Production and Displacement
Damage on Microstructural Evolution andMechanical Properties in Helium‐Implanted
Austenitic
StainlessSteelandFerritic/Martensitic Steel, E. Wakai, S. Nogami, A.
Hasegawa, N. Okubo, S. Takaya, T. Tanno, Y.
Nagae, T. Suzudo, H. Abe, M. Yamaguchi & K.
Aoto, Mater. Sci. Forum 1024, 53 (2021).
13) Positron annihilation studies of defect structureof (TiZrHfNbV)N nitride coatings under Xe14+ 200
MeV ion irradiation, A.D. Pogrebnjak, A.A.
Bagdasaryan, P. Horodek, V. Tarelnyk, V.V.
Buranich, H. Amekura, N. Okubo, N. Ishikawa &V.M. Beresnev, Mater. Lett. 303, 130548 (2021).
14) Nanopore Formation in CeO2 Single Crystal by
Ion Irradiation: A Molecular Dynamics Study, Y.
Sasajima, R. Kaminaga, N. Ishikawa & A. Iwase,
Quantum Beam Sci. 5(4), 32 (2021).
15) Blue‐shift in optical bandgap of sprayed
nanocrystalline Cu2ZnSnS4 thin films induced by
200 MeV Xe swift heavy ions irradiation, M.
Khoualed, F.Z. Boutebakh, A. Chettah, H.
Amekura, N. Ishikawa, S. Ghemid, N. Attaf & M.S.
Aida, J. Mater. Sci.: Mater. Electron. 32, 25516(2021).
16) Combined effect of flux pinning by three‐directional columnar defects in a field‐angularregion of high‐Tc superconductors, T. Sueyoshi, R.

Enokihata, Y. Hidaka, M. Irie, T. Fujiyoshi, Y.
Okuno
&
N.
Ishikawa,
Physica
C:
Superconductivity and its Applications 582,
1353824 (2021).
17) Summation of Flux Pinning by Columnar
Defects Tilted at Different Angles in YBCO Thin
Films, T. Sueyoshi, R. Enokihata, H. Yamaguchi, T.
Fujiyoshi, Y. Okuno & N. Ishikawa, IEEE
Transactions on Applied Superconductivity 31(5),8000305 (2021).
18) Artificial neural network molecular mechanics
of iron grain boundaries, Y. Shiihara, R. Kanazawa,
D. Matsunaka, I. Lobzenko, T. Tsuru, M. Kohyama& H. Mori, Scripta Mater. 207, 114268 (2022).
19) Inclination of self‐interstitial dumbbells inmolybdenum and tungsten: A first‐principles
study, T. Suzudo & T. Tsuru, AIP Adv. 11(6),065012 (2021).
20) Perspectives on multiscale modelling andexperiments
toacceleratematerials
development for fusion, M.R. Gilbert, K. Arakawa,
Z. Bergstrom, M.J. Caturla, S.L. Dudarev, F. Gao,
A.M. Goryaeva, S.Y. Hu, X. Hu, R.J. Kurtz, A.
Litnovsky, J. Marian, M.‐C. Marinica, E. Martinez,
E.A. Marquis, D.R. Mason, B.N. Nguyen, P. Olsson,
Y. Osetskiy, D. Senor, W. Setyawan, M.P. Short, T.
Suzudo, J.R. Trelewicz, T. Tsuru, G.S. Was, B.D.
Wirth, L. Yang, Y. Zhang & S.J. Zinkle, J. Nucl.
Mater. 554, 153113 (2021).
21) Hydrogen‐Trapping Energy in Screw and Edge
Dislocations in Aluminum: First‐Principles
Calculations, M. Yamaguchi, M. Itakura, T. Tsuru& K.‐i. Ebihara, Mater. Trans. 62(5), 582 (2021).
22) Variation in formation and migration of self‐interstitial atom clusters in electron irradiatedcopper with material purity and specimen
preparation method, Y. Satoh, Y. Abe, K. Ohkubo& T. Tanioka, Philosophical Magazine 102(12),1152 (2022).

Books
1)

“Positron annihilation age momentum
correlation (AMOC) measurement” of “Chapter
4 positoron – two photons angular correlation”,
T. Hirade, Positron Sciences ‐from Basic to
Application‐ / Jpn. Positron Sci. Soc. (2021) (inJapanese).
2) "Chapter 2.4, First principles calculations of
dislocation cores" of "2 Simulation of plastonand plaston induced phenomena", T. Tsuru, The
Plaston concept; Plastic deformation in
structural materials / Springer (2021).

PatentRADIATION DETECTOR
DETECTOR”,
Japanese(2021.10.22)

1) Hirade T., Ando T., Manabe K. & Ueda D.,“POSITRON
ANNIHILATION
LIFETIME
MEASURING DEVICE, ADJUSTMENT METHOD OF

31

AND RADIATION
Patent6964877

FY2021 NSEC Publications

Research Group for High Temperature Science on Fuel Materials
Papers1) High temperature reaction of multiple eutectic‐
component system: The case of solid metallic Zr
and molten stainless steel‐B4C, T. Sumita, M.
Kobata, M. Takano & A. Ikeda‐Ohno, Materialia
20, 101197 (2021).
2) Direct in‐situ temperature measurement forlamp‐based heating device, T. Sumita, A. Sudo, M.

Takano & A. Ikeda‐Ohno, Sci. Tech. Advanced
Mater.: Methods 2(1), 50 (2022).
3) Concepts and basic designs of various nuclear
fuels (4) : Metallic fuels for fast reactors andnitride fuels for ADS, T. Ogata & M. Takano, J. theAtomic Energy Soc. Jpn. 63(7), 541 (2021) (inJapanese).

JAEA Reports
1) Development of high melting temperature
measurement system by laser spot heating, T.
Iwasa & T. Arima, JAEA‐Tech. 2021‐036 (2022) (inJapanese).
2) Re‐examinations of MA fuel composition for
accelerator‐driven system and its heat removal,
T. Sugawara, D. Moriguchi, Y. Ban, Y. Tsubata, M.
Takano & K. Nishihara, JAEA‐Res. 2021‐008(2021) (in Japanese).
3) Carrying‐out of whole nuclear fuel materials in
Plutonium Research Building No.1, J. Inagawa, Y.
Kitatsuji, H. Otobe, M. Nakada M. Takano, H. Akie,
O. Shimizu, M. Komuro, H. Ohura, I. Nagai, K.
Harada, K. Suzuki, R. Morita, J. Ishikawa, O.
Tachihara, T. Kida & M. Watanabe, JAEA‐Tec.
2021‐001 (2021) (in Japanese).

Development Group for LWR Advanced Technology
Papers1) Study on solubility of cesium iodide and cesium
molybdate in water at around room temperature,
J. Imoto, K. Nakajima & M. Osaka, Trans. theAtomic Energy Soc. Jpn. 20(4), 179 (2021) (inJapanese).
2) Revaporization Behavior of Cesium and Iodine
Compounds from Their Deposits in the Steam–
Boron Atmosphere, M. Rizaal, S. Miwa, E. Suzuki,
J. Imoto, M. Osaka & M. Gouëllo, ACS Omega
6(48), 32695 (2021).
3) Formation of Type A glassy cesium‐bearing
microparticles from HEPA filter materials in Unit
3 during Fukushima Dai‐ichi NPS accident; From
viewpoint of similarity in silicate glass
composition, A. Hidaka, Proc. ICAPP 2021 (2021).
4) A new method of measuring ruthenium activity
in ruthenium‐containing alloys by using
thermogravimetric analysis, J. Liu, K. Nakajima, S.
Miwa, N. Shirasu & M. Osaka, J. Nucl. Sci. Tech.
59(4), 484 (2022).
5) Phase stability of Cs‐Si‐O and Cs‐Si‐Fe‐O
compounds on stainless steel, C. Suzuki, K.
Nakajima & M. Osaka, J. Nucl. Sci. Tech. 59(3),345 (2022).
6) Cesium Chemistry in the LWR severe accident
and towards the decommissioning ofFukushima Daiichi Nuclear Power Station, M.
Osaka, M. Gouëllo & K. Nakajima, J. Nucl. Sci.
Tech. 59(3), 292 (2022).
7) Development of accident tolerant FeCrAl‐ODS
fuel cladding for BWRs in Japan, K. Sakamoto, Y.
Miura, S. Ukai, N.H. Oono, A. Kimura, A. Yamaji,
K. Kusagaya, S. Takano, T. Kondo, T. Ikegawa, I.
Ioka & S. Yamashita, J. Nucl. Mater. 557, 153276(2021).
8) How the Cesium‐bearing microparticles weregenerated? ; Inference of an interdiscipinary
researcher, A. Hidaka, J. the Atomic Energy Soc.
Jpn. 63(9), 679 (2021) (in Japanese).
9) Toward evaluation of cesium chemistry duringtransportation in a boiling water reactor : Effects
of boron on cesium chemistry, S. Miwa, N.
Miyahara, K. Nakajima, J. Imoto & E. Suzuki, J. theAtomic Energy Soc. Jpn. 63(12), 825 (2021) (inJapanese).

32

FY2021 NSEC Publications

Nuclear Chemistry Division
Research Group for Radiochemistry
Papers7) Solvent Extraction of Cesium Using DtBuDB18C6
into Various Organic Solvents, Y. Sasaki, K. Morita,
Y. Kitatsuji, K. Ito & K. Yoshizuka, Solvent Extr. Res.
Dev., Jpn. 28(2), 121 (2021).
8) Radiation Chemistry Provides Nanoscopic
Insights into the Role of Intermediate Phases in
CeO2 Mesocrystal Formation, Z. Li, D. Piankova, Y.
Yang, Y. Kumagai, H. Zschiesche, M. Jonsson, N.V.
Tarakina & I.L. Soroka, Angewandte Chemie (Int’lEd.) 61(6), e202112204 (2022).
9) Density functional study on Am(III)/Eu(III)selectivity using crown ether type ligands, Y.
Fukasawa, M. Kaneko & S. Nakashima, J.
Radioanal. Nucl. Chem. 329(1), 77 (2021).
10) Synergistic solvent extraction of lanthanide ionswith mixtures of D2EHPA and MIDPA in
phosphonium‐based ionic liquids, M. Matsumiya,
D. Nomizu, Y. Tsuchida & Y. Sasaki,
Hydrometallurgy 199, 105539 (2021).
11) Recovery of tungsten compounds from spent
tungstophosphate catalyst using leaching,solvent extraction with phosphonium‐basedionic liquids and precipitation, T. Igosawa, M.
Matsumiya & Y. Sasaki, Hydrometallurgy 208,
105803 (2022).
12) Separation of Light and Middle Lanthanides
Using Multistage Extraction with Diglycolamide
Extractant, T. Matsutani, Y. Sasaki, S. Katsuta,
Anal. Sci. 37(11), 1603 (2021).
13) Density functional study aiming to elucidate
separation mechanisms of minor actinides andrare earths, M. Kaneko, J. the Atomic Energy Soc.
Jpn. 64(1), 30 (2022) (in Japanese).

1) Uranium dissolution and uranyl peroxide
formation by immersion of simulated fuel debris
in aqueous H2O2 solution, Y. Kumagai, R. Kusaka,
M. Nakada, M. Watanabe, D. Akiyama, A.
Kirishima, N. Sato & T. Sasaki, J. Nucl. Sci. Tech.
59(8), 961 (2022).
2) Zeolite‐assisted radiolysis of aromatic chlorides
mitigating influence of coexisting ions in water
matrix, Y. Kumagai, A. Kimura, M. Taguchi & M.
Watanabe, Radiat. Phys. Chem. 191, 109831(2022).
3) The kinetics and mechanism of H2O2
decomposition at the U3O8 surface inbicarbonate solution, J. McGrady, Y. Kumagai, M.
Watanabe, A. Kirishima, D. Akiyama, A. Kitamura& S. Kimuro, RSC Adv. 11(46), 28940 (2021).
4) Stoichiometry of Lanthanide–Phosphate
Complexes at the Water Surface Studied Using
VibrationalSum
Frequency
Generation
Spectroscopy and DFT Calculations, R. Kusaka &M. Watanabe, J. Phys. Chem. B 125(24), 6727
(2021).
5) Prediction of Stability Constants for Novel
Chelates Design in Minor Actinides Partitioning
over Lanthanides Using Density Functional
Theory Calculation, M. Kaneko, Y. Sasaki, E. Wada,
M. Nakase & K. Takeshita, Chem. Lett. 50(10),1765 (2021).
6) Density Functional Theory Study on the Ir‐193
Mössbauer Spectroscopic Parameters of Vaska’sComplexes and Their Oxidative Adducts, M.
Kaneko & S. Nakashima, Inorg. Chem. 60(17),12740 (2021).

Book(II)‐Method and practice‐/ Tohoku Univ. Press(2021) (in Japanese).

1) N. Sato, A. Kirishima, M. Watanabe, T. Sasaki, A.
Uehara & S. Takeda, The Chemistry of Uranium

Patents
1) Inokuchi Y., Hirata S., Meiji S., Kusaka R. &Watanabe M., “Sample table for infrared
spectroscopy”, Japanese Patent Application
2021‐161781 (2021.9.30)

2) Sasaki Y., Suzuki S., Ito K., Takahashi Y., Kaneko M.,
Omori T. & Asano K., “METHOD FOR SEPARATINGMETAL FROM EACH OTHER”, Japanese Patent
6886616 (2021.5.19)

33

FY2021 NSEC Publications

Research Group for Analytical Chemistry
Papers1) Design of Microchannel Suitable for Packing withAnion Exchange Resins: Uranium Separationfrom Seawater Containing a Large Amount ofCesium, K. Ouchi, T. Tsukahara, A. Brandt, Y. Muto,
N. Nabatame & Y. Kitatsuji, Anal. Sci. 37(12),1789 (2021).
2) Selective Pd Separation from SimulatedRadioactive Liquid Waste by Precipitation Using
Xenon Lamp Irradiation for a Simplified
Procedure, T. Yomogida, M. Saeki, S. Morii, H.
Ohba & Y. Kitatsuji, Anal. Sci. 37(12), 1843 (2021).
3) Dense radical formation in L‐alanine‐3,3,3‐d3
and L‐alanine‐d4 by 1.5 keV soft X‐ray irradiation,
S. Nakagawa, T. Oka, K. Fujii & A. Yokoya, Radiat.
Phys. Chem. 192, 109884 (2022).
4) Design for detecting recycling muon after muon‐
catalyzed fusion reaction in solid hydrogenisotope target, K. Okutsu, T. Yamashita, Y. Kino, R.
Nakashima, K. Miyashita, K. Yasuda, S. Okada, M.
Sato, T. Oka, N. Kawamura, S. Kanda, K.
Shimomura, P. Strasser, S. Takeshita, M. Tampo,
S. Doiuchi, Y. Nagatani, H. Natori, S. Nishimura, A.
Datt Pant, Y. Miyake & K. Ishida, Fusion Eng.
Design 170, 112712 (2021).
5) Time evolution calculation of muon catalysed
fusion: Emission of recycling muons from a two‐layer hydrogen film, T. Yamashita, K. Okutsu, Y.
Kino, R. Nakashima, K. Miyashita, K. Yasuda, S.
Okada, M. Sato, T. Oka, N. Kawamura, S. Kanda,
K. Shimomura, P. Strasser, S. Takeshita, M. Tampo,
S. Doiuchi, Y. Nagatani, H. Natori, S. Nishimura, A.
Datt Pant, Y. Miyake & K. Ishida, Fusion Eng.
Design 169, 112580 (2021).
6) Rapid analysis of Sr‐90 in cattle bone and tooth

samples by inductively coupled plasma mass
spectrometry, K. Koarai, M. Matsueda, J. Aoki, K.
Yanagisawa, M. Terashima, K. Fujiwara, Y. Kino, T.
Oka, A. Takahashi, T. Suzuki, Y. Shimizu, M. Chiba,
K. Osaka, K. Sasaki, T. Sekine, M. Fukumoto, H.
Shinoda, A. Kitamura & H. Abe, J. Anal. At.
Spectrom. 36, 1678 (2021).
7) Radioactivity and radionuclides in deciduous
teeth formed before the Fukushima‐Daiichi
Nuclear Power Plant accident, A. Takahashi, M.
Chiba, A. Tanahara, J. Aida, Y. Shimizu, T. Suzuki,
S. Murakami, K. Koarai, T. Ono, T. Oka, J. Ikeyama,
O. Kaneko, M. Unno, K. Hirose, T. Ohno, Y. Kino, T.
Sekine, K. Osaka, K. Sasaki & H. Shinoda, Sci. Rep.
11, 10335 (2021).
8) Solvent Extraction of Cesium Using DtBuDB18C6
into Various Organic Solvents, Y. Sasaki, K. Morita,
Y. Kitatsuji, K. Ito & K. Yoshizuka, Solvent Extr. Res.
Dev., Jpn. 28(2), 121 (2021).
9) Dispersive XAFS Study on the Laser‐Induced
Reduction of a Rh3+ Ion Complex: Presence of a
Rh+ Intermediate in Direct Photoreduction, M.
Saeki, D. Matsumura, R. Nakanishi, T. Yomogida,
T. Tsuji, H. Saitoh & H. Ohba, J. Phys. Chem. C
126(12), 5607 (2020).
10) Development of dose estimation method using
wild animal teeth for low dose exposure, Y.
Mitsuyasu, T. Oka, A. Takahashi, K. Koarai, Y. Kino,
K. Okutsu, T. Sekine, T. Yamashita, Y. Shimizu, M.
Chiba, T. Suzuki, K. Osaka, K. Sasaki, Y. Urushihara,
M. Suzuki, M. Fukumoto & H. Shinoda, Proc.
22nd WS on Environ. Radioactivity, 91 (2021) (inJapanese).

JAEA Report
Harada, K. Suzuki, R. Morita, J. Ishikawa, O.
Tachihara, T. Kida & M. Watanabe, JAEA‐Tec.
2021‐001 (2021) (in Japanese).

1) Carrying‐out of whole nuclear fuel materials in
Plutonium Research Building No.1, J. Inagawa, Y.
Kitatsuji, H. Otobe, M. Nakada M. Takano, H. Akie,
O. Shimizu, M. Komuro, H. Ohura, I. Nagai, K.

34

FY2021 NSEC Publications

Environment and Radiation Sciences Division
Research Group for Environmental Science
PapersCs‐137 fallout, M. Ota & J. Koarashi, Sci. the Total
Environ. 816, 151587 (2022).
8) Development of local‐scale high‐resolution
atmospheric dispersion model using large‐eddy
simulation part 6: introduction of detailed dose
calculation method, H. Nakayama, D. Satoh, H.
Nagai & H. Terada, J. Nucl. Sci. Tech. 58(9), 949(2021).
9) Development of local‐scale high‐resolution
atmospheric dispersion and dose assessment
system, H. Nakayama, N. Onodera, D. Satoh, H.
Nagai, Y. Hasegawa & Y. Idomura, J. Nucl. Sci. Tech.
59(10), 1314 (2022).
10) Soil microbial community responding tomoderately elevated nitrogen deposition in a
Japanese cool temperate forest surrounded byfertilized grasslands, H. Nagano, M. Nakayama, G.
Katata, K. Fukushima, T. Yamaguchi, M.
Watanabe, T. Kondo, M. Atarashi‐Andoh, T.
Kubota, R. Tateno & J. Koarashi, Soil Sci. Plant
Nutrition 67(5), 606 (2021).
11) Dynamics of radiocaesium within forests inFukushima—results and analysis of a modelinter‐comparison, S. Hashimoto, T. Tanaka, M.
Komatsu, M.‐A. Gonze, W. Sakashita, H. Kurikami,
K. Nishina, M. Ota, S. Ohashi, P. Calmon, F.
Coppin, N. Imamura, S. Hayashi, K. Hirai, P.
Hurtevent, J. Koarashi, T. Manaka, S. Miura, Y.
Shinomiya, G. Shaw & Y. Thiry, J. Environ.
Radioactivity 238‐239, 106721 (2021).
12) Distribution, dynamics, and fate of radiocesium
derived from FDNPP accident in the ocean, S.
Otosaka, Y. Kamidaira, T. Ikenoue & H. Kawamura,
J. Nucl. Sci. Tech. 59(4), 409 (2022).
13) Atmospheric dispersion database system
WSPEEDI‐DB; Quicker calculation of atmosphericdispersion of radioactive materials under various
meteorological and release conditions, H. Terada& H. Nagai, Isotope News 775, 44 (2021) (inJapanese).

1) Large‐Eddy Simulation of Plume Dispersion in theCentral District of Oklahoma City by Couplingwith a Mesoscale Meteorological Simulation
Model and Observation, H. Nakayama, T. Takemi& T. Yoshida, Atmosphere 12(7), 889 (2021).
2) Toward Development of a Framework for
Prediction System of Local‐Scale Atmospheric
Dispersion Based on a Coupling of LES‐Databaseand On‐Site Meteorological Observation, H.
Nakayama, T. Yoshida, H. Terada & M. Kadowaki,
Atmosphere 12(7), 899 (2021).
3) Evaluation of uncertainties derived frommeteorological forecast inputs in plumedirections predicted by atmospheric dispersion
simulations, T. Yoshida, H. Nagai, H. Terada, K.
Tsuduki & H. Sawa, J. Nucl. Sci. Tech. 59(1), 55(2022).
4) Validity of the source term for the Fukushima
Dai‐ichi Nuclear Power Station accident
estimated using local‐scale atmosphericdispersion simulations to reproduce the large‐
scale atmospheric dispersion of Cs‐137, M.
Kadowaki, A. Furuno, H. Nagai, H. Kawamura, H.
Terada, K. Tsuduki & H. El‐Assad, J. Environ.
Radioactivity 237, 106704 (2021).
5) A modeling study on the oceanic dispersion andsedimentation of radionuclides off the coast of
Fukushima, Y. Kamidaira, Y. Uchiyama, H.
Kawamura, T. Kobayashi & S. Otosaka, J. Environ.
Radioactivity 238‐239, 106724 (2021).
6) Spatial variations in radiocesium deposition andlitter–soil distribution in a mountainous forest
catchment affected by the Fukushima nuclear
accident, M. Atarashi‐Andoh, J. Koarashi, K.
Tsuduki, E. Takeuchi, S. Nishimura, K. Muto & T.
Matsunaga, J. Environ. Radioactivity 238‐239,
106725 (2021).
7) Contamination processes of tree components inJapanese forest ecosystems affected by the
Fukushima Daiichi Nuclear Power Plant accident

JAEA Report1) Ocean current data obtained by Acoustic
Doppler Current Profiler across the Tsugaru Strait(Joint research), H. Kawamura, N. Hirose, T.

Nakayama & T. Ito, JAEA‐Data/Code 2021‐004(2021).

35

FY2021 NSEC Publications

Research Group for Radiation Transport Analysis
Papers1)

Implementation of simplified stochastic
microdosimetric kinetic models into PHITS for
application to radiation treatment planning, T.
Sato, S. Hashimoto, T. Inaniwa, K. Takada &H.
Kumada, Int. J. Radiat. Biol. 97(10), 1450 (2021).
2) Benchmark study of particle and heavy‐ion
transport code system using shielding integral
benchmark archive and database for accelerator‐
shielding experiments, Y. Iwamoto, S. Hashimoto,T. Sato, N. Matsuda, S. Kunieda, Y. Çelik, N.
Furutachi & K. Niita, J. Nucl. Sci. Tech. 59(5), 665(2022).
3) ANALYSES OF H*(10) DOSE RATES MEASURED IN
ENVIRONMENTCONTAMINATED
BY
RADIOACTIVE CAESIUM: CORRECTION OF
DIRECTIONAL DEPENDENCE OF SCINTILLATION
DETECTORS, S. Tsuda, M. Tanigaki, T. Yoshida, R.
Okumura & K. Saito, Radiat. Protection
Dosimetry 193(3‐4), 228 (2021).
4) Improvements in the particle and heavy‐ion
transport code system (PHITS) for simulating
neutron‐response functions and detection
efficiencies of a liquid organic scintillator, D.
Satoh & T. Sato, J. Nucl. Sci. Tech. 59(8), 1047
(2022).
5) Medical application of particle and heavy ion
transport code system PHITS, T. Furuta & T. Sato,
Radiol. Phys. Tech. 14, 215 (2021).
6) Variation of Internal Doses Caused byDifferences in Physical Characteristics between
the Average Japanese and the ICRP’s Reference
Man Which Is Based on the Standard Data of
Caucasians in the Dosimetric Methodology inConformity to the 2007 Recommendations, K.
Manabe, K. Sato & F. Takahashi, J. Nucl. Sci. Tech.
59(5), 656 (2022).
7) Development and validation of proton track‐
structure model applicable to arbitrary materials,
T. Ogawa, Y. Hirata, Y. Matsuya & T. Kai, Sci. Rep.
11, 24401 (2021).
8) Verification of KURBUC‐based ion track structuremode for proton and carbon ions in the PHITS
code, Y. Matsuya, T. Kai, T. Sato, T. Liamsuwan, K.
Sasaki & H. Nikjoo, Phys. Med. Biol. 66(6),06NT02 (2021).
9) Oxygen enhancement ratios of cancer cells after
exposure to intensity modulated x‐ray fields:
DNA damage and cell survival, Y. Matsuya, S.J.
McMahon, K.T. Butterworth, S. Naijo, I. Nara, Y.
Yachi, R. Saga, M. Ishikawa, T. Sato, H. Date & K.M.

Prise, Phys. Med. Biol. 66(7), 075014 (2021).
10) Track‐structure modes in particle and heavy ion
transport code system (PHITS): application toradiobiological research, Y. Matsuya, T. Kai, T.
Sato, T. Ogawa, Y. Hirata, Y. Yoshii, A. Parisi & T.
Liamsuwan, Int. J. Radiat. Biol. 98(2), 148 (2022).
11) Theoretical and experimental estimation of therelative optically stimulated luminescence
efficiency of an optical‐fiber‐based BaFBr:Eu
detector for swift ions, Y. Hirata, T. Sato, K.
Watanabe, T. Ogawa, A. Parisi & A. Uritani, J. Nucl.
Sci. Tech. 59(7), 915 (2022).
12) Japanese pediatric and adult atomic bomb
survivor dosimetry: potential improvements
using the J45 phantom series and modern Monte
Carlo transport, K.T. Griffin, T. Sato, S. Funamoto,
K. Chizhov, S. Domal, C. Paulbeck, W. Bolch, H.M.
Cullings, S. Egbert, A. Endo, N. Hertel & C. Lee,Rad. Environ. Biophys. 61(1), 73 (2022).
13) Probabilistic risk assessment of solar particle
events considering the cost of countermeasures
to reduce the aviation radiation dose, M. Fujita,
T. Sato, S. Saito & Y. Yamashiki, Sci. Rep. 11, 17091(2021).
14)
PSTEP:
projectforsolar–terrestrial
environment prediction, K. Kusano, K. Ichimoto,
M. Ishii, Y. Miyoshi, S. Yoden, H. Akiyoshi, A. Asai,
Y. Ebihara, H. Fujiwara, T.‐N. Goto, Y. Hanaoka, H.
Hayakawa, K. Hosokawa, H. Hotta, K. Hozumi, S.
Imada, K. Iwai, T. Iyemori, H. Jin, R. Kataoka, Y.
Katoh, T. Kikuchi, Y. Kubo, S. Kurita, H.
Matsumoto, T. Mitani, H. Miyahara, Y. Miyoshi, T.
Nagatsuma, A. Nakamizo, S. Nakamura, H.
Nakata, N. Nishizuka, Y. Otsuka, S. Saito, S. Saito,
T. Sakurai, T. Sato, T. Shimizu, H. Shinagawa, K.
Shiokawa, D. Shiota, T. Takashima, C. Tao, S.
Toriumi, S. Ueno, K. Watanabe, S. Watari, S.
Yashiro, K. Yoshida & A. Yoshikawa, Earth, Planets& Space 73, 159 (2021).
15) Space weather benchmarks on Japanesesociety, M. Ishii, D. Shiota, C. Tao, Y. Ebihara, H.
Fujiwara, T. Ishii, K. Ichimoto, R. Kataoka, K. Koga,
Y. Kubo, K. Kusano, Y. Miyoshi, T. Nagatsuma, A.
Nakamizo, M. Nakamura, M. Nishioka, S. Saito, T.
Sato, T. Tsugawa & S. Yoden, Earth, Planets &Space 73, 108 (2021).
16) Development of local‐scale high‐resolution
atmospheric dispersion model using large‐eddy
simulation part 6: introduction of detailed dose
calculation method, H. Nakayama, D. Satoh, H.

36

FY2021 NSEC Publications
Nagai & K. Hashimoto, J. Radioanal. Nucl. Chem.
330(3), 913 (2021).
21)
4‐Methylumbelliferone
administration
enhancesradiosensitivityof
human
fibrosarcoma by intercellular communication, R.
Saga, Y. Matsuya, R. Takahashi, K. Hasegawa, H.
Date & Y. Hosokawa, Sci. Rep. 11, 8258 (2021).
22) Estimated Isotopic Compositions of Yb in
Enriched Yb‐176 for Producing Lu‐177 with HighRadionuclide Purity by 176Yb(d,x)177Lu, Y. Nagai,
M. Kawabata, S. Hashimoto, K. Tsukada, K.
Hashimoto, S. Motoishi, H. Saeki, A. Motomura,
F. Minato & M. Itoh, J. Phys. Soc. Jpn. 91, 044201(2022).
23) Track‐structure mode for electrons, protons
and carbon ions in the PHITS code, Y. Matsuya, T.
Kai, T. Ogawa, Y. Hirata & T. Sato, 放射線化学
Rad. Chem. 112, 15 (2021) (in Japanese).
24) Model development for estimating effects ofboron neutron capture therapy, H. Fukunaga & Y.
Matsuya, 放 射 線 生 物 研 究 Rad. biol. res.
communications 56(2), 208 (2021) (in Japanese).

Nagai & H. Terada, J. Nucl. Sci. Tech. 58(9), 949(2021).
17) Development of local‐scale high‐resolution
atmospheric dispersion and dose assessment
system, H. Nakayama, N. Onodera, D. Satoh, H.
Nagai, Y. Hasegawa & Y. Idomura, J. Nucl. Sci. Tech.
59(10), 1314 (2022).
18) Technical Note: validation of a material
assignment method for a retrospective study ofcarbon‐ion radiotherapy using Monte Carlosimulation, W. Chang, Y. Koba, T. Furuta, S. Yonai,
S. Hashimoto, S. Matsumoto & T. Sato, J. Radiat.
Res. 62(5), 846 (2021).
19) Influence of distant scatterer on air kerma
measurement in the evaluation of diagnostic X‐
rays using Monte Carlo simulation, M. Tominaga,
Y. Nagayasu, M. Sasaki, T. Furuta, H. Hayashi, M.
Oita, Y. Nishiyama & A. Haga, Radiol. Phys. Tech.
14, 381 (2021).
20) Large scale production of Cu‐64 and Cu‐67 via
the 64Zn(n, p)64Cu and 68Zn(n, np/d)67Cu
reactions using accelerator neutrons, M.
Kawabata, S. Motoishi, A. Ohta, A. Motomura, H.
Saeki, K. Tsukada, S. Hashimoto, N. Iwamoto, Y.

JAEA Report
1)

K. Manabe, JAEA‐Res. 2021‐001 (2021) (inJapanese).

Internal dose coefficients for various
gastrointestinal absorption fractions (Contract
research), J. Hirouchi, Y. Tokashiki, S. Takahara &Partitioning and Transmutation Technology Division
Research Group for Partitioning
PapersAntimony in nitric acid solution using TDdDGA, Y.
Nakamura, S. Ogawa, S. Takahashi, C. Kato, S.
Fukutani, T. Matsumura, H. Suzuki & T. Fujii,
KURNS PROGRESS REPORT 2020, 205 (2021).

1) Solvent Extraction of Cesium Using DtBuDB18C6
into Various Organic Solvents, Y. Sasaki, K. Morita,
Y. Kitatsuji, K. Ito & K. Yoshizuka, Solvent Extr. Res.
Dev., Jpn. 28(2), 121 (2021).
2) CO9‐3 The solvent extraction behavior of

JAEA Reports
2) Re‐examinations of MA fuel composition for
accelerator‐driven system and its heat removal,
T. Sugawara, D. Moriguchi, Y. Ban, Y. Tsubata, M.
Takano & K. Nishihara, JAEA‐Res. 2021‐008(2021) (in Japanese).

1) Evaluation of the mass transfer coefficients forthe minor actinide separation; Evaluation by thesingle drop method, A. Sakamoto, S. Kibe, K.
Kawanobe, K. Fujisaku, Y. Sano, M. Takeuchi, H.
Suzuki, Y. Tsubata, Y. Ban & T. Matsumura, JAEA‐
Res. 2021‐003 (2021) (in Japanese).

37

FY2021 NSEC Publications

Research Group for Nuclear Transmutation System
Papers1) G‐HyND: a hybrid nuclear data estimator with
Gaussian processes, H. Iwamoto, O. Iwamoto &S. Kunieda, J. Nucl. Sci. Tech. 59(3), 334 (2022).
2) Subcriticality determination methodology during
fuel loading of accelerator‐driven system, R.
Katano, J. Nucl. Sci. Tech. 59(3), 368 (2022).
3) Non‐proliferation features in partitioning andtransmutation cycle using accelerator‐driven
system, 2; Evaluation of “Material Attractiveness”
of uranium in ADS fuel assembly, A. Oizumi, T.
Sugawara & H. Sagara, Proc. the 42nd INMMJ
Annual Meeting (2021) (in Japanese).
4) CFD ANALYSIS OF NATURAL CIRCULATION IN LBE‐
COOLED ACCELERATOR‐DRIVEN SYSTEM, T.
Sugawara, K. Ichihara, K. Hanzawa, K. Nishihara,
N. Watanabe & A. Ono, Proc. NURETH‐19 (19thInternational Topical Meeting on Nuclear
Reactor Thermal Hydraulics) (2022).
5) Material attractiveness evaluation of fuelassembly of accelerator‐driven system fornuclear security and non‐proliferation, A. Oizumi,
T. Sugawara & H. Sagara, Annals Nucl. Energy 169,
108951 (2022).
6) NMB4.0: development of integrated nuclear fuelcycle simulator from the front to back‐end, T.
Okamura, R. Katano, A. Oizumi, K. Nishihara, M.

Nakase, H. Asano & K. Takeshita, EPJ Nucl. Sci.
Tech. 7, 19 (2021).
7) Experimental Analyses of Am‐243 and U‐235
Fission Reaction Rates at Kyoto University Critical
Assembly, C.H. Pyeon, A. Oizumi & M. Fukushima,
Nucl. Sci. Eng. 195(11), 1144 (2021).
8) CO3‐4 Measurements of Np‐237 and Am‐243
Fission Reaction Rates in Lead Region at A‐coreof KUCA, A. Oizumi, R. Katano, R. Kojima, M.
Fukushima, K. Tsujimoto & C.H. Pyeon, KURNSPROGRESS REPORT 2020, 104 (2021).
9) CO3‐2 Void reactivity measurements of lead andbismuth in the KUCA‐A core, R. Katano, A. Oizumi,
M. Fukushima & C.H. Pyeon, KURNS PROGRESSREPORT 2020, 102 (2021).
10) Session of Sub‐committee on Nuclear Data;
Application of advanced data science to nuclear
data, 3; Application of machine learning to
nuclear‐data evaluation study and high‐energy
particle transport calculation, H. Iwamoto, Nucl.
Data News 129, 19 (2021) (in Japanese).
11) Material Attractiveness Evaluation of Actinides
in Pyroprocessing Facility for Partitioning andTransmutation Cycle, A. Oizumi & H. Sagara, Proc.
the INMM & ESARDA Joint Annual Meeting(2021).

JAEA Reports
Japanese).
3) User manual of NMB4.0, T. Okamura, K.
Nishihara, R. Katano, A. Oizumi, M. Nakase, H.
Asano & K. Takeshita, JAEA‐Data/Code 2021‐016(2022) (in Japanese).
4) Determination of accelerator parameters for
subcriticality measurement of accelerator‐driven
system before operation, R. Katano, K. Nishihara,
Y. Kondo & S.‐i. Meigo, JAEA‐Res. 2021‐016(2022) (in Japanese).

1) Re‐examinations of MA fuel composition for
accelerator‐driven system and its heat removal,
T. Sugawara, D. Moriguchi, Y. Ban, Y. Tsubata, M.
Takano & K. Nishihara, JAEA‐Res. 2021‐008(2021) (in Japanese).
2) Radiation shielding analysis of the upper
structure of an accelerator‐driven system, H.
Iwamoto, S.‐i. Meigo, K. Nakano, B. Yee‐Rendon,
R. Katano, T. Sgawara, K. Nishihara, T. Sasa & F.
Maekawa, JAEA‐Res. 2021‐012 (2022) (inResearch Group for MA Transmutation Fuel Cycle
Paper1) Electrochemical recovery of Zr and Cd frommolten chloride salts for reprocessing of used

nitride fuels, T. Murakami & H. Hayashi, J Nucl.
Mater. 558, 153330 (2022).

38

FY2021 NSEC Publications

Nuclear Science and Engineering Center
Paper1) Improvement of Engineer Ethics Education Using
Resilience Engineering Concept, K. Oba, A.

Yoshizawa & M. Kitamura, J. JSEE 69(3), 3_3(2021) (in Japanese).

39Editorial Board‐ Chief Editor:
HAYASHI Hirokazu‐ Editors:
TADA Kenichi, TAKAKI Seiya, KUMAGAI Yuta,
OGAWA Tatsuhiko, SATO Takumi,
KATO Chiaki, NAKAHARA Yukio

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/