Yang, Z.*; Wang, G.-J.*; Wu, J.-J.*; Oka, Makoto; Zhu, S.-L.*
Journal of High Energy Physics (Internet), 2023(1), p.058_1 - 058_19, 2023/01
Combining the quark model, the quark-pair-creation mechanism and interaction, we have investigated the near-threshold -wave states in the framework of the Hamiltonian effective field theory. With the heavy quark flavor symmetry, all the parameters are determined in the sector by fitting the lattice data. The masses of the bottom-strange partners of the and are predicted, which are well consistent with the lattice QCD simulation. The two -wave states are the mixtures of the bare core and component. Moreover, we find a crossing point between the energy levels with and without the interaction Hamiltonian in the finite volume spectrum in the case, which corresponds to a CDD (Castillejo-Dalitz-Dyson) zero in the -matrix of the scattering. This CDD zero will help deepen the insights of the near-threshold states and can be examined by future lattice calculation.
Ebihara, Kenichi; Sekine, Daiki*; Sakiyama, Yuji*; Takahashi, Jun*; Takai, Kenichi*; Omura, Tomohiko*
International Journal of Hydrogen Energy, 14 Pages, 2023/00
To understand hydrogen embrittlement (HE), which is one of the stress corrosion cracking of steel materials, it is necessary to know the H distribution in steel, which can be effectively interpreted by numerical simulation of thermal desorption spectra. In weld metals and TRIP steels, residual austenite significantly influences the spectra, but a clear H distribution is not well known. In this study, an originally coded two-dimensional model was used to numerically simulate the previously reported spectra of high-carbon ferritic-austenitic duplex stainless steels, and it was found that H is mainly trapped at the carbide surface when the amount of H in the steel is low and at the duplex interface when the amount of H is high. It was also found that the thickness dependence of the H desorption peak for the interface trap site is caused by a different reason than the conventional one.
Kimizuka, Hajime*; Thomsen, B.; Shiga, Motoyuki
Journal of Physics; Energy (Internet), 4(3), p.034004_1 - 034004_13, 2022/07
Artificial neural network-based interatomic potential for a system of palladium and hydrogen was developed, and path integral molecular dynamics simulations were performed to study the quantum diffusion of hydrogen isotopes in palladium crystals. Diffusion coefficients of light and heavy hydrogen were calculated over a wide temperature range of 50-1500 K to clarify the difference in diffusion mechanisms at low and high temperatures.
Osamura, Naohiro*; Gubler, P.; Yamanaka, Nodoka*
Journal of High Energy Physics (Internet), 2022(6), p.072_1 - 072_30, 2022/06
Uno, Kenta*; Tanida, Kiyoshi; Belle Collaboration*; 181 of others*
Journal of High Energy Physics (Internet), 2021(10), p.19_1 - 19_12, 2021/10
Li, L. K.*; Tanida, Kiyoshi; Belle Collaboration*; 187 of others*
Journal of High Energy Physics (Internet), 2021(9), p.75_1 - 75_21, 2021/09
Tanaka, Nobuyuki; Takegami, Hiroaki; Noguchi, Hiroki; Kamiji, Yu; Myagmarjav, O.; Kubo, Shinji
International Journal of Hydrogen Energy, 46(55), p.27891 - 27904, 2021/08
The thermochemical water-splitting iodine-sulfur (IS) process enables producing hydrogen. In a previous operation procedure, after the components of the unit operations were individually started, they were connected at the same time. However, it was challenging to stably interconnect the components. This study introduces a new loop operation, subdividing the process configuration into four sections before transferring the continuous operation. The proposed loop operation was validated analyzing the material and heat balances of each section. The calculated results showed that the material balances of respective loop sections were closed. The loop operation mode would transfer to the continuous operation by connect all sections. Regarding the switching of operation modes, the material and heat balance showed no or little difference, indicating that two operation modes could only be changed by switching the pipelines. Consequently, the loop sections could be individually operated to stabilize the IS process system, and the loop operation could be smoothly transferred to the continuous operation.
Myagmarjav, O.; Shibata, Ai*; Tanaka, Nobuyuki; Noguchi, Hiroki; Kubo, Shinji; Nomura, Mikihiro*; Takegami, Hiroaki
International Journal of Hydrogen Energy, 46(56), p.28435 - 28449, 2021/08
Noguchi, Hiroki; Kamiji, Yu; Tanaka, Nobuyuki; Takegami, Hiroaki; Iwatsuki, Jin; Kasahara, Seiji; Myagmarjav, O.; Imai, Yoshiyuki; Kubo, Shinji
International Journal of Hydrogen Energy, 46(43), p.22328 - 22343, 2021/06
An iodine-sulfur process offers the potential for mass producing hydrogen with high-efficiency, and it uses high-temperature heat sources, including HTGR, solar heat, and waste heat of industries. R&D tasks are essential to confirm the integrity of the components that are made of industrial materials and the stability of hydrogen production in harsh working conditions. A test facility for producing hydrogen was constructed from corrosion-resistant components made of industrial materials. For stable hydrogen production, technical issues for instrumental improvements (i.e., stable pumping of the HIx solution, improving the quality control of glass-lined steel, prevention of I precipitation using a water removal technique in a Bunsen reactor) were solved. The entire process was successfully operated for 150 h at the rate of 30 L/h. The integrity of components and the operational stability of the hydrogen production facility in harsh working conditions were demonstrated.
Jia, S.*; Tanida, Kiyoshi; Belle Collaboration*; 186 of others*
Journal of High Energy Physics (Internet), 2021(6), p.160_1 - 160_13, 2021/06
Mizuk, R.*; Tanida, Kiyoshi; Belle Collaboration*; 188 of others*
Journal of High Energy Physics (Internet), 2021(6), p.137_1 - 137_35, 2021/06
Park, S.-H.*; Tanida, Kiyoshi; Belle Collaboration*; 217 of others*
Journal of High Energy Physics (Internet), 2021(4), p.191_1 - 191_15, 2021/04
Reinecke, E.-A.*; Takenaka, Keisuke*; Ono, Hitomi*; Kita, Tomoaki*; Taniguchi, Masashi*; Nishihata, Yasuo; Hino, Ryutaro; Tanaka, Hirohisa*
International Journal of Hydrogen Energy, 46(23), p.12511 - 12521, 2021/03
The safe decommissioning as well as decontamination of the radioactive waste resulting from the nuclear accident in Fukushima Daiichi represents a huge task for the next decade. At present, research and development on long-term safe storage containers has become an urgent task with international cooperation in Japan. One challenge is the generation of hydrogen and oxygen in significant amounts by means of radiolysis inside the containers, as the nuclear waste contains a large portion of sea water. The generation of radiolysis gases may lead to a significant pressure build-up inside the containers and to the formation of flammable gases with the risk of ignition and the loss of integrity. In the framework of the project "R&D on technology for reducing concentration of flammable gases generated in long-term waste storage containers" funded by the Japanese Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT), the potential application of catalytic recombiner devices inside the storage containers is investigated. In this context, a suitable catalyst based on the so-called intelligent automotive catalyst for use in a recombiner is under consideration. The catalyst is originally developed and mass-produced for automotive exhaust gas purification, and is characterized by having a self-healing function of precious metals (Pd, Pt and Rh) dissolved as a solid solution in the perovskite type oxides. The basic features of this catalyst have been tested in an experimental program. The test series in the REKO-4 facility has revealed the basic characteristics of the catalyst required for designing the recombiner system.
Choudhury, S.*; Tanida, Kiyoshi; Belle Collaboration*; 221 of others*
Journal of High Energy Physics (Internet), 2021(3), p.105_1 - 105_19, 2021/03
Journal of Energy and Power Engineering, 14(8), p.251 - 258, 2020/08
Thermal expansion behavior was investigated for evaluation of the core support plate expansion reactivity in the Unprotected Loss of Heat Sink reactor trip failure event. A possibility of mechanical restraint was investigated in thermal expansion of the core structure for the prototype fast breeder reactor Monju. The reactor core expansion was simulated in a three-dimensional finite element analysis model of the reactor vessel considering detailed temperature distribution of the sodium coolant based on the thermal-hydraulic analysis result of the whole core model. It was found that the thermal expansion of the core was not restrained in the ULOHS evert, although part of the core structure is mechanically restrained.
Tanaka, Nobuyuki; Noguchi, Hiroki; Kamiji, Yu; Takegami, Hiroaki; Kubo, Shinji
International Journal of Hydrogen Energy, 45(35), p.17557 - 17561, 2020/07
The thermochemical water-splitting iodine-sulfur (IS) process requires corrosion-resistant materials owing to usage of a mixture of HI-I-HO. Fluoropolymers, such as PTFE and PFA, are adaptable as lining materials for protecting plant components. However, there has been a concern: PTFE and PFA have the ability to permeate various permeants. From the viewpoint of corrosion, the permeation of HI and I should be evaluated to improve the integrity of the IS process. In this study, permeation tests on PTFE and PFA membranes were performed to measure the permeated fluxes of HI and I, and the effects of the operating conditions on them were investigated. The introduction of a permeability parameter could be successful for normalizing the permeated fluxes for a specific membrane thickness and a vapor pressure. Then, the empirical formula of the permeability was given as an Arrhenius-type equation to use as a plant design.
Ito, Etsuko*; Nagai, Yuki
Journal of High Energy Physics (Internet), 2020(7), p.7_1 - 7_31, 2020/07
no abstracts in English
Sawada, Shinichi*; Kimura, Takehiro*; Nishijima, Haruyuki*; Kodaira, Takahide*; Tanaka, Nobuyuki; Kubo, Shinji; Imabayashi, Shinichiro*; Nomura, Mikihiro*; Yamaki, Tetsuya*
International Journal of Hydrogen Energy, 45(27), p.13814 - 13820, 2020/05
An electrochemical membrane Bunsen reaction using a cation exchange membrane (CEM) is a key to achieving an iodine-sulfur (IS) thermochemical water splitting process for mass-production of hydrogen. In this study, we prepared both the radiation-grafted CEM with a high ion exchange capacity (IEC) and the highly-porous Au-electroplated anode, and then used them for the membrane Bunsen reaction to reduce the cell overvoltage. The high-IEC grafted CEM exhibited low resistivity for proton transport, while the porous Au anode had a large effective surface area for anodic SO oxidation reaction. As a result, the cell overvoltage for the membrane Bunsen reaction was significantly reduced to 0.21 V at 200 mA/cm, which was only one-third of that of the previous test using the commercial CEM and non-porous anode. From the analysis of the current-voltage characteristics, employment of the grafted CEM was found to be more effective for the overvoltage reduction compared to the porous Au anode.
Tokunaga, Tomoharu*; Kuno, Kohei*; Kawakami, Takumi*; Yamamoto, Takahisa*; Yoshigoe, Akitaka
International Journal of Hydrogen Energy, 45(28), p.14347 - 14353, 2020/05
To understand the catalytic behavior of graphite and carbon black with mainly 6-membered rings with sp bonds for H production by CH decomposition, fullerenes with 6-membered rings and also those comprising 5- and 7-membered rings with sp bonds was investigated using gas chromatography, XPS and TEM analysis. From these analysis, it is anticipated that the ring structures without 6-membered rings in carbon materials with sp bonding contribute to the catalytic behavior for CH decomposition at a low temperature of 400C.