研究者詳細 - 小山　佳一

論文 - 小山　佳一

分割表示 496 件中 161 - 180 件目／全件表示 >>

K. Koyama, Y. Mitsui, E.S. Choi, Y. Ikehara, E. Palm, and K. Watanabe . Controlled Equilibrium State of Ferromagnetic MnBi by High Magnetic Fields . Proceedings of the 22nd International Workshop on Rare-Earth Permanent Magnets and their Applications, (Nagasaki, 2012) 110 - 113 2012年9月

T. Inomata, M. Matsukawa, D. Kimura, Y. Yamato, S. Kobayashi, R. Suryanarayanan, S. Nimori, K. Koyama, K. Takahashi, K. Watanabe, N. Kobayashi . Suppression of the low-temperature phase-separated state under pressure in (Eu1-xGdx)0.6Sr0.4MnO3 (x= 0, 0.1) . J. Magn. Magn. Mater.324 3863 - 3869 2012年7月査読

折橋広樹、満永大輔、廣井政彦、三井好古、高橋弘紀、渡辺和雄、小山佳一 . 強磁場 X 線回折実験による Mn1.8Co0.2Sb の磁場中結晶評価 . 日本金属学会誌76 ( 4 ) 246 - 250 2012年4月査読

S. Ebisu, K. Koyama, T. Horikoshi, M. Kokita, S. Nagata . Extremely broad hysteresis in the magnetization process of α-Dy <inf>2</inf>S<inf>3</inf> single crystal induced by high field cooling . Journal of Physics: Conference Series400 ( PART 3 ) 2012年

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：Journal of Physics: Conference Series

α-Dy2S3 possesses orthorhombic crystal structure having two crystallograpically inequivalent Dy sites. Magnetization process of α-Dy2S3 single crystal after cooling in the high magnetic field of 18 T has been investigated. The magnetization under the field of 18 T along the α-axis on the cooling process from 150 K shows step-like rises at 70 and 40 K and reaches about 9 μB per one Dy3+ at 1.5 K. This value, which corresponds to 90 % of full saturation moment of Dy3+, is much larger than 6 μB obtained at the same conditions after cooling in no magnetic field (zero-field cooling; ZFC). After cooling to 1.5 K, the magnetization while decreasing field shows abrupt drops at 3.0 and 1.7 T, and then comes to 0 μB at 0 T. Subsequently, while increasing field, the magnetization demonstrates a similar curve to that obtained after ZFC without step-like rise below 13.1 T. At μ0H = 13.1 T, the magnetization rises suddenly and agrees with the curve for the decreasing process. This irreversible magnetization process yields extremely broad hysteresis having width of μ0ΔH = 11.4 T. Broader hysteresis and narrower one are also observed at 4.2 and 10 K, respectively.

DOI： 10.1088/1742-6596/400/3/032010

Web of Science

Scopus

折橋広樹, 満永大輔, 廣井政彦, 三井好古, 高橋弘紀, 渡辺和雄, 小山佳一 . 強磁場 X 線回折実験による Mn<sub>1.8</sub>Co<sub>0.2</sub>Sb の磁場中結晶評価 . 日本金属学会誌76 ( 4 ) 246 - 250 2012年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：公益社団法人日本金属学会

Measurements of magnetization, electrical resistivity and high field X-ray powder diffraction (XRD) were carried out for polycrystalline Mn 1.8Co 0.2Sb in magnetic fields up to 5 T in 4.2-300 K temperature range, in order to investigate the structural properties affected by magnetic fields. In a zero field, the compound shows the first-order magnetic transition from the ferrimagnetic (FRI) to antiferromagnetic (AFM) states at T t = 145 K with decreasing temperature. By applying magnetic fields of 5 T, T tdecreased to 60 K with thermal hysteresis of 35 K. From the XRD measurements, not only the AFM phase but also the residual FRI phase was confirmed even at 10 K in cooling process under 5 T. Results obtained indicate that the residual FRI phase is kinetically arrested. © 2012 The Japan Institute of Metals.

DOI： 10.2320/jinstmet.76.246

Web of Science

Scopus

CiNii Research

Y. Mitsui,K. Koyama,K. Takahashi, and Kazuo Watanabe . Development of an x-ray diffraction camera used in magnetic fields up to 10 T . Rev. Sci. Instrum.82 125104(1) - 125104(6) 2011年12月査読

廣井政彦、小山佳一、伊藤昌和、重田出 . ヘリウム液化装置 . 鹿児島大学理学部紀要44 27 - 32 2011年12月

Ito M., Nagi Y., Kado N., Urakawa S., Ogawa T., Kondo A., Koyama K., Watanabe K., Kindo K. . Magnetic properties of spinel FeCr<inf>2</inf>S<inf>4</inf> in high magnetic field . Journal of Magnetism and Magnetic Materials323 ( 24 ) 3290 - 3293 2011年12月査読

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Magnetism and Magnetic Materials

We studied temperature and magnetic field dependence of magnetization, M(T) and M(B), on thiospinel FeCr2S4. We observed a step-like anomaly at TOO∼9K for M(T) attributed to an orbital order transition in magnetic field 0 <B≤7T. Furthermore, also for M(B), the step-like anomaly appears at Bc∼5.5T below TOO. This suggests an existence of a magnetic phase boundary at Bc in T<TOO. Because the anomaly at Bc of M(B) exists in the orbital ordered phase, the spin structure of FeCr2S4 in T<TOO is strongly coupled with the lattice of the system. © 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2011.07.041

Web of Science

Scopus

K. Oikawa, Y. Mitsui, K. Koyama, K. Anzai . Thermodynamic Assessment of the Bi-Mn System . MATERIALS TRANSACTIONS52 ( 11 ) 2032 - 2039 2011年11月査読

M. Yamamoto, S. Sekida, T. Fukuda, T. Kakeshita, K. Takahashi,K. Koyama, H. Nojiri . A new type of FCT martensite phase in single-crystalline Fe(3)Pt Invar alloy . JOURNAL OF ALLOYS AND COMPOUNDS509 ( 34 ) 8530 - 8533 2011年8月査読

Yamamoto M., Sekida S., Fukuda T., Kakeshita T., Takahashi K., Koyama K., Nojiri H. . A new type of FCT martensite phase in single-crystalline Fe<inf>3</inf>Pt Invar alloy . Journal of Alloys and Compounds509 ( 34 ) 8530 - 8533 2011年8月査読

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Alloys and Compounds

Martensitic transformation in a highly ordered Fe3Pt has been investigated by magnetization and X-ray diffraction measurements. We confirmed that a new type of face-centered tetragonal (FCT) martensite phase appears below 60 K in Fe3Pt with a degree of order S = 0.88. The tetragonality c/a gradually increases with decreasing temperature, and is approximately 1.005 at 10 K. This is in contrast to the tetragonality c/a < 1 generally observed in the FCT martensite with a degree of order less than 0.8. The spontaneous magnetization increases in association with the transformation. © 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2011.06.035

Web of Science

Scopus

H. Kato,K. Koyama, K. Takahashi . Crystallization of Nd-Co-B nanocomposite ribbons in high magnetic fields . JOURNAL OF APPLIED PHYSICS109 ( 7 ) 07A726 2011年4月査読

Y. Murano, M. Matsukawa, S. Ohuchi, S. Kobayashi, S. Nimori, R. Suryanarayanan, K. Koyama, N. Kobayashi . Effect of pressure on the magnetic, transport, and thermal-transport properties of the electron-doped manganite CaMn1-xSbxO3 . Phys. Rev. B 83 ( 5 ) 54437 - -13 2011年2月査読

K. Koyama, Y. Mitsui, E.S. Choi, Y. Ikehara, E.C. Palm, K. Watanabe . Change of the equilibrium state of ferromagnetic MnBi by high magnetic fields . J. Alloys. Comp.509 L78 - L80 2011年1月査読

R.Y. Umetsu K. Ito, K. Koyama, T. Kanomata, K. Ishida and R. Kainuma, . Kinetic arrest behavior in martensitic transformation of NiCoMnSn metamagnetic shape memory alloy . J. Alloys and Comp.509 1389 - 1393 2011年1月査読

M. Ito, Y. Nagi,N. Kado, S. Urakawa,T. Ogawa, A. Kondo,K. Koyama, K. Watanabe, K. Kindo . Magnetic properties of spinel FeCr(2)S(4) in high magnetic field . JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS323 ( 24 ) 3290 - 3293 2011年査読

Koshi Takenaka, Takashi Shibayama, Kazuko Asano, Keiichi Koyama . Magnetostructural Correlations in Nitrogen-Deficient Antiperovskite Mn3CuN1-delta . JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN79 ( 7 ) 2010年7月査読

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PHYSICAL SOC JAPAN

Ferromagnetic shape memory effects of antiperovskite Mn3CuN are markedly altered by nitrogen deficiency. The martensitic transformation occurs at a lower temperature than ferromagnetic ordering for nitrogen-deficient Mn3CuN0.8, although they both occur simultaneously for stoichiometric Mn3CuN. In the martensitic phase, Mn3CuN0.8 contracts in a direction parallel to the magnetic field, in contrast to the expansion observed in Mn3CuN, implying that the easy axis is converted from the longer a axis in Mn3CuN to the shorter c axis in Mn3CuN0.8. The operating magnetic field for magnetostriction drastically decreases for Mn3CuN0.8, suggesting a possible supermagnetostriction around the critical compositional region for the easy-axis conversion.

DOI： 10.1143/JPSJ.79.073706

Web of Science

H Nishihara, Y Furutani, T Wada, T Kanomata, K Kobayashi, R Kainuma, K Ishida, K Koyama, K Watanabe . Hyperfine coupling constant for 59Co estimated from a high-field susceptibility and high-field NMR shift in ferromagnetic Co2TiGa and Co2VGa . J. Phys. Conf. Ser.200 32052 2010年1月査読

K. Takenaka, T. Shibayama, K. Asano and K. Koyama . Magnetostructural Correlations in Nitrogen-Deficient Antiperovskite Mn3CuN1-δ . J. Phys. Soc. Jpn.79 73706 2010年査読

Y.Mitsui, K. Koyama, W. Ito, R.Y. Umetsu, R. Kainuma, K. Watanabe . Observation of Reverse Transformation in Metamagnetic Shape Memory Alloy Ni40Co10Mn34Al16 by High-Field X-Ray Diffraction Measurements . Materials Transactions51 1648 - 1650 2010年査読

　前のページ - 次のページ　

<小山 佳一>

論文 - 小山 佳一

<小山　佳一>

論文 - 小山　佳一