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61.
Fine particles of -FeO(OH) were prepared using the56Fe isotope and the surfaces of the particles were coated with extremely thin57Fe(III) layers. Mössbauer results show that the Fe(III) ions in the top surface layer are involved in the magnetic order and occupy two kinds of surface sites. Both of the two exchange field at surface sites, estimated from the temperature dependences of the hyperfine fields, are smaller than the bulk value. The decrease of exchange fields at the surface sites corresponds to the reduced number of neighboring magnetic ions at each site. 相似文献
62.
By means of a Carleman estimate, we obtain several observability inequalities by internal observation for hyperbolic equations with lower-order terms. Also, we apply our observability results to an exact controllability problem and an inverse wave source problem. 相似文献
63.
Papadimitriou V Barker A Briere RA Gibbons LK Makoff G Patterson JR Somalwar S Wah YW Winstein B Winston R Woods M Yamamoto H Swallow EC Bock GJ Coleman R Enagonio J Hsiung YB Ramberg E Stanfield K Tschirhart R Yamanaka T Gollin GD Karlsson M Okamitsu JK Debu P Peyaud B Turlay R Vallage B 《Physical review D: Particles and fields》1991,44(3):R573-R576
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Bond IA Budding E Conway MJ Fenton KB Fujii H Fujii Z Fujimoto M Hasegawa H Hayashida N Honda M Hotta N Humble JE Kabe S Kasahara K Kifune T Masaike A Matsubara Y Mitsui K Miura Y Mori M Murakami K Muraki Y Nagano M Nakamura K Nakamura T Norris PM Ohashi Y Okada A Saito T Sakata M Sato H Shibata S Shima M Storey JR Tanimori T Teshima M Torii S Uchino K Watase Y Woodhams MD Yamamoto Y Yock PC Yuda T 《Physical review letters》1988,61(20):2292-2295
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Y. Yamamoto K. Fujisawa T. Takemura S. Kita 《International Journal of Infrared and Millimeter Waves》1988,9(1):29-40
Measurements have been done in the millimeter wave region on a composite waveguide which comprises a dielectric rod waveguide connecting two metal rectangular waveguides. Such a waveguide has been used by us in a Josephson harmonic mixer installed in a small metal cryostat, to prevent the thermal invasion from outside environment and to transmit both signal and LO waves with small losses. The measured transmission loss, that is caused mainly by the coupling loss between metal rectangular waveguides (TE10 mode) and a dielectric rod waveguide (HE11 mode), has been less than 2dB in the frequency range of 52–104 GHz. 相似文献
70.
S Tonegawa K Hashimoto K Ikada YH Lin H Shishido Y Haga TD Matsuda E Yamamoto Y Onuki H Ikeda Y Matsuda T Shibauchi 《Physical review letters》2012,109(3):036401
We report the first observation of cyclotron resonance in the hidden-order phase of ultraclean URu_{2}Si_{2} crystals, which allows the full determination of angle-dependent electron-mass structure of the main Fermi-surface sheets. We find an anomalous splitting of the sharpest resonance line under in-plane magnetic-field rotation. This is most naturally explained by the domain formation, which breaks the fourfold rotational symmetry of the underlying tetragonal lattice. The results reveal the emergence of an in-plane mass anisotropy with hot spots along the [110] direction, which can account for the anisotropic in-plane magnetic susceptibility reported recently. This is consistent with the "nematic" Fermi liquid state, in which itinerant electrons have unidirectional correlations. 相似文献