Consequence analysis of a postulated nuclear excursion in BWR spent fuel pool using 1/ spectrum model of randomization

Simanullang, I.; Yamane, Yuichi; Kikuchi, Takeo; Tonoike, Kotaro

Annals of Nuclear Energy, 147, p.107675_1 - 107675_6, 2020/11

https://doi.org/10.1016/j.anucene.2020.107675

Identified charged hadron production in collisions at = 200 and 62.4 GeV

Adare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.

Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06

https://doi.org/10.1103/PhysRevC.83.064903

Transverse momentum distributions and yields for , and in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as and scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.

Corrosion behavior of SUS316 clad in alkalis molybdate melt

Nagai, Takayuki; Kikuchi, Kotaro*; Kano, Yoshiharu*; Fukushima, Mineo

Nihon Genshiryoku Gakkai Wabun Rombunshi, 7(4), p.370 - 379, 2008/12

https://doi.org/10.3327/taesj.J07.050

Study of a new pyrochemical processing using alkaline molybdate melt has been carrying out as a candidate reprocessing process for spent oxide fuels. In our previous study, we had confirmed that melting of UO pellet into a molten NaMoO-MoO and electrolytic recovering of UO from the melt included uranyl ions. In this report, the corrosion behavior of the SUS316 cladding tube in molten NaMoO-MoO was evaluated, and we confirmed the dissolution of SUS316 elements into the melt when the amount of additional MoO was excess. And, it is necessary to understand an appropriate amount of additional MoO since the result of this study.

Kinetic parameter measurement on low enriched uranyl nitrate solution with single unit cores (600, 280T, 800) of STACY

Tonoike, Kotaro; Miyoshi, Yoshinori; Kikuchi, Tsukasa*; Yamamoto, Toshihiro

Journal of Nuclear Science and Technology, 39(11), p.1227 - 1236, 2002/11

https://doi.org/10.3327/jnst.39.1227

Kinetic parameter of low enriched uranyl nitrate solution was measured by the pulsed neutron source method in the STACY. This measurement was repeated systematically over several uranium concentrations from 193.7 gU/ to 432.1 gU/. Used core tanks were two cylindrical tanks whose diameters are 600 mm and 800 mm and one slab tank which has 280 mm thickness and 700 mm width. In this report, experimental data such as solution conditions, critical solution level for each solution condition, subcritical solution levels where measurements were conducted, measured decay time constants of prompt neutron and extrapolated values are described as well as basic principle of the pulsed neutron source method. values were evaluated also by computation with the diffusion code CITATION in SRAC and the nuclear data library JENDL 3.2. Both experimental and computational values show good agreement.

Cyclic voltammetry for high concentration lanthanide ions in molten LiCl-KCl eutectic

Nagai, Takayuki; Kikuchi, Kotaro*; Hirano, Hiroyasu; Fukasawa, Kazuhito*; Uehara, Akihiro*; Yamana, Hajimu*

no journal, , 

In the dry reprocessing process for spent nuclear fuel by the electro-metallurgical method, we are studying the online monitoring technique of dissolved ion concentration in molten LiCl-KCl eutectic. In this study, the cyclic voltammetry was carried out in the molten LiCl-KCl eutectic added lanthanide chlorides (NdCl, etc.) and we confirmed that the peak current density by the reductive reaction of dissolved ions increased in proportion to the dissolved ion concentration until about 4 mol%.

Corrosion behavior of Fe, Cr, and Ni in molten sodium molybdate

Nagai, Takayuki; Kikuchi, Kotaro*; Kano, Yoshiharu*; Hirano, Hiroyasu

no journal, , 

On the dry reprocessing process study by using a molten sodium molybdate, the SUS316 stainless steel of clad material was dissolved into the melt. In this study, we carried out the immersed corrosion test of Fe, Cr, and Ni in molten sodium molybdate, and estimated the corrosion behavior of these material and dissolution content in the melt.

Corrosion behavior of SUS316 stainless steel in molten sodium molybdate

Nagai, Takayuki; Kikuchi, Kotaro*; Kano, Yoshiharu*; Fukushima, Mineo

no journal, , 

The study of a pyrochemical process by using molten alkaline molybdate has been carried out as a candidate reprocessing process for spent oxide fuels. In this study, the immersed corrosion tests of SUS316 tube were carried out in molten NaMoO-MoO mixtures with MoO mole fractions. Results showed that the concentration of dissolved iron and nickel species in the melt increased with the increase of the MoO mole fraction, whereas the concentrations of dissolved chromium species remained constant at low values, independent of the MoO content. It is found that the corrosion of SUS316 specimens in molten NaMoO-MoO mixtures proceeds with the iron and nickel preferably dissolved into the melt and with chromium-rich corrosion films formed at the surface.