Muon spin relaxation in mixed perovskite (LaAlO)(SrAlTaO) with

Ito, Takashi; Higemoto, Wataru; Koda, Akihiro*; Nakamura, Jumpei*; Shimomura, Koichiro*

Interactions (Internet), 245(1), p.25_1 - 25_7, 2024/12

https://doi.org/10.1007/s10751-024-01866-5

Thermophysical properties of americium-containing barium plutonate

Tanaka, Kosuke; Sato, Isamu; Hirosawa, Takashi; Kurosaki, Ken*; Muta, Hiroaki*; Yamanaka, Shinsuke*

Journal of Nuclear Science and Technology, 52(10), p.1285 - 1289, 2015/10

https://doi.org/10.1080/00223131.2015.1029554

Polycrystalline specimens of americium-containing barium plutonate have been prepared by mixing the appropriate amounts of (PuAm)O and BaCO powders followed by reacting and sintering at 1600 K under the flowing gas atmosphere of dry-air. The sintered specimens had a single phase of orthorhombic perovskite structure and were crack-free. The elastic moduli were determined from the longitudinal and shear sound velocities. The Debye temperature was also determined from the sound velocities and lattice parameter measurements. The thermal conductivity was calculated from the measured density at room temperature, literature values of heat capacity, and thermal diffusivity measured by laser flash method in vacuum. The thermal conductivity of americium-containing barium plutonate was roughly independent of the temperature and was almost the same magnitude as that of BaPuO and BaUO.

Addendum to CaMnO rqrq

Machida, Akihiko; Moritomo, Yutaka*; Oyama, Kenji*

Journal of the Physical Society of Japan, 72(5), P. 1312, 2003/05

In order to investigate interrelation between the lattice structure and the magnetic structure, we have performed Rietveld structural analysis on the neutron powder patterns for TbCaMnO at low temperature. In the concentration range of , we observed the Bragg reflections due to the CE-like- and C-type structures. In this range, the powder patterns were reproduce by the two-phase model with and symmetries. The fractions of these phases change against concentration . This variation of the fraction for the phase is similar to the variation of the integrated intensities of the CE-like-type magnetic Bragg reflections. This indicates that the phase is responsible for the CE-like spin-ordering. Furthermore, we discussed interrelation between the detailed lattice structure and magnetic structure.

Bulk-sensitive photoemission spectroscopy of FeMoO double perovskites (=Sr, Ba)

Kang, J.-S.*; Kim, J. H.*; Sekiyama, Akira*; Kasai, Shuichi*; Suga, Shigemasa*; Han, S. W.*; Kim, K. H.*; Muro, Takayuki*; Saito, Yuji; Hwang, C.*; et al.

Physical Review B, 66(11), p.113105_1 - 113105_4, 2002/09

https://doi.org/10.1103/PhysRevB.66.113105

The electronic structures of SrFeMoO (SFMO) and BaFeMoO (BFMO) double perovskites have been investigated using Fe 2p-3d resonant photoemission spectroscopy (PES) and the Cooper minimum in the Mo 4d photoionization cross section. The states close to the Fermi level are found to have a strongly mixed Mo–Fe t character, indicating that the Fe valence is far from pure 3+. The Fe 2p x-ray absorption spectroscopy spectra reveal the mixed-valent Fe –Fe configurations, and a larger Fe component for BFMO than for SFMO, suggesting an operative double exchange interaction. The valence-band PES spectra reveal good agreement with the local-spin-density-approximation (LSDA+U) calculation.

Influence of TiO and NaO additives on properties synthetic rock of fly ash from municipal waste incinerator

Mitamura, Hisayoshi; Bamba, Tsunetaka; Maeda, Toshikatsu

Nihon Seramikkusu Kyokai Gakujutsu Rombunshi, 110(1277), p.55 - 59, 2002/01

https://doi.org/10.2109/jcersj.110.55

Influence of additives and hot-pressing temperature on properties of the synthetic rock was investigated, which was developed for making harmless and stabilizing fly ash from municipal waste incinerator. Sintering test at 1200C for 16 h revealed that addition of 20 and 1.5 wt% of TiO and NaO, respectively, is necessary for preparation of dense products. X-ray diffractometry showed that these additives promoted the formation of perovskite (CaTiO) and gehlenite (CaAlSiO) minerals. During hot pressing, bulk density of the synthetic rock increased steeply with temperature between 1000 and 1100C. On the other hand, its open porosity decreased rapidly with temperature between 1050 and 1150C. These facts imply that the temperature of 1100150C is practical in hot pressing of fly ash.

Synthesis and magnetic properties of LnTiO(Ln=Pr and Nd)

Yoshii, Kenji

Journal of Solid State Chemistry, 149(1), p.354 - 359, 2000/01

no abstracts in English

Moessbauer spectroscopic study on Eu-Nb complex oxides

Saeki, Masakatsu; Nakada, Masami; ; Nakamura, Akio

SIF Conf. Proc., Vol. 50 (ICAME-95), 0, p.119 - 122, 1996/00

no abstracts in English

Positive muons in SrTiO; Electronic structure of the hydrogen-like defects and their potential use in depth-resolved detection of oxygen vacancies

Ito, Takashi; Higemoto, Wataru; Koda, Akihiro*; Shimomura, Koichiro*

no journal, ,