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141.
Hiroshi Sugaya Takafumi Arai Youichi Ueda 《Journal of magnetism and magnetic materials》1993,120(1-3):106-111
A contact printing model is introduced to explain the re-recording dip in overwrite recording. The first signal on a recording medium is transferred to the medium surface, where the second signal increases the susceptibility to transfer the S-1 signal magnetically with opposite phase. The output signal of S-1 will be compensated by the transferred signal, and will be zero, which is supposed to be the re-recording dip. The contact printing model is confirmed by experiments. 相似文献
142.
Takafumi Seto Kenji Koga Hiroyuki Akinaga Fumiyoshi Takano Takaaki Orii Makoto Hirasawa 《Journal of nanoparticle research》2006,8(3-4):371-378
Monodispersed CoPt alloy nanoparticles were synthesized by a pulsed laser ablation (PLA) technique coupled with a low-pressure operating differential mobility analyzer (LP-DMA). The CoPt alloy nanoparticles were generated by laser ablating a solid Co–Pt target. In CoPt alloy nanoparticles synthesized from a target with a Co composition of 75 at%, the nanoparticle surfaces were covered by an oxide layer and exhibited a core-shell structure. In contrast, no shell was observed in particles generated from a target with a Co:Pt ratio of 50:50 at%. According to an EDX analysis, the compositions of the individual nanoparticles were almost the same as that of the target material. Finally, the magnetic hysteresis loops of the CoPt alloy nanoparticles exhibited ferromagnetism. 相似文献
143.
Yuji Sano Kotaro Shirai Naoto Takahata Takafumi Hirata Neil C Sturchio 《Analytical sciences》2005,21(9):1091-1097
Concentrations of minor (Mg and Sr) and trace (Ba and U) elements in four natural calcium carbonate samples were first analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after chemical dissolution and calibrated against a standard dolomite. Their homogeneities were checked by in situ laser ablation (LA) ICP-MS with 10-20 spots. The carbonate samples were measured by using a high lateral resolution secondary ion mass spectrometer (Nano-SIMS NS50). A approximately 4 nA O- primary beam was used to sputter a 5-6-microm diameter crater on the sample surface, and secondary positive ions were extracted for mass analysis using an accelerating voltage of 8 kV and a Mattauch-Herzog geometry. A multi-collector system was adjusted to detect 26Mg+, 43Ca+, 88Sr+, 138Ba+, 238U16O+ and 238U16O2+ ions at the same time. A resolving power of 2500-5000 at 10% peak height was attained by an entrance slit set at 40 microm, and each exit slit at 50 microm with adequate flat-topped peaks. The observed 26Mg/43Ca, 88Sr/43Ca, 138Ba/43Ca and 238U16O2/43Ca ratios agreed well with those measured by LA-ICP-MS. Foraminifera shells were analyzed at 5-6 microm scale by Nano-SIMS. There was a large variation of the Mg/Ca ratios, up to +/- 38%, even in a single fragment of the shell, suggesting that although the ratios provide a useful paleoceanographic proxy at bulk scale, they may reflect a more complex pattern at < 10 microm scale. 相似文献
144.
M. Matsui M. Suzuki K. Mizuno K. Funabiki S. Okada T. Kobayashi M. Kadowaki 《Liquid crystals》2004,31(11):1463-1467
Novel dichroic fluorescent 2- and 2,7-disubstituted perfluorophenazines exhibit emission maxima in the range 570-600 nm in MLC-2039. The order parameter of fluorescence was observed in the range 0.29-0.49. 相似文献
145.
146.
A formal total synthesis of (±)-gibberellin A12 (1) was achieved by employing methyl (±)-7,16-dioxo-17-norkauran-19-oate (13) as a relay compound. 相似文献
147.
Takafumi Isogai 《Annals of the Institute of Statistical Mathematics》1985,37(1):289-301
Summary Some extension of Haldane's multivariate median is carried out by minimization principle of a specified distance function.
Then, making use of the median, three types of measures of multivariate skewness are introduced and their asymptotic null
distributions are obtained. 相似文献
148.
Jun Hosoi Tetsuo Oikawa Masao Inoue Yoshio Matsui Tadashi Endo 《Journal of Electron Spectroscopy and Related Phenomena》1982,27(3):243-254
An interband π plasmon and π* edge have been observed in the spectrum of hexagonal boron nitride (h-BN). This result is in good agreement with that 相似文献
149.
150.