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991.
Suzuki Y Kubota H Tulapurkar A Nozaki T 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2011,369(1951):3658-3678
Efficient control and detection of spins are the most important tasks in spintronics. The current and voltage applied to a magnetic tunnel junction may exert a torque on the magnetic thin layer in the junction and cause its reversal or continuous precession. The discovery of the giant tunnelling magnetoresistance effect in ferromagnetic tunnelling junctions using an MgO barrier enabled us to obtain a large signal output from the magnetization reversal and precession. Also, the interplay of large spin configuration-electric conduction coupling provides highly nonlinear effects like the spin-torque diode effect. The negative resistance effect and amplification using it are predicted. A new discovery about a voltage-induced magnetic anisotropy change in Fe ultrathin films is also discussed. 相似文献
992.
Yasuhiro Hamada Kiyotaka TakedaRyuichiro Goto Hideki Kubota 《Energy and Buildings》2011,43(12):3680-3684
This paper describes field experiments and numerical simulations on hybrid utilization of renewable energy and fuel cells for a residential energy system. It presents results of empirical testing and evaluation of hybrid utilization involving solar energy. First, field experiments were conducted on an electric power and domestic hot water supply system that uses both solar energy and fuel cells. The system achieved a large amount of reduction in primary energy consumption compared with conventional systems. Secondly, a simulation was performed on the optimum scale and effect of introduction of the system. The simulation results proposed the optimum capacities of the solar energy utilization and fuel cells to minimize primary energy consumption of the system. 相似文献
993.
ABSTRACT: The aroma property of boiled squid was quantitatively described using 10 sensory attributes. From screening experiments based on a Plackett-Burman design, pH and parts of squid were selected as significant factors for generating the "cooked squid" aroma. Squid samples prepared according to a 3-level full-factorial design for pH and parts showed that "sweet,""roasted shrimp,""cooked fish," and "cooked squid" scores were higher in both muscle and muscle with skin at pH 6.5. Response surface models calculated for each of the attributes showed how pH and parts influenced their strength. Partial least squares regression analysis applied to the sensory and GC-MS data revealed that every attribute could be predictable (R2 ≥ 0.956) using a small number of informative peaks. 相似文献
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995.
T. Takabatake R. W. McCallum M. Kubota F. Pobell 《Journal of Low Temperature Physics》1984,55(1-2):111-125
The low-temperature magnetic properties of EuMo6S8 and EuMo6Se8 have been investigated by means of the151Eu Mössbauer effect between 0.06 and 300 K and by measuring dc and ac magnetic susceptibilities between 0.017 and 3 K. A sharp deviation of the dc susceptibility from Curie-Weiss behavior indicates that EuMo6S8 and EuMo6Se8 order magnetically at 0.40 and 0.85 K, respectively. A drastic broadening of the Mössbauer linewidth of both compounds occurs at 0.9 K. The broadening above the magnetic ordering temperature for EuMo6S8 is explained in terms of slow relaxation effects arising from the depopulation of higher crystal field levels of Eu2+ ions. The combination of Mössbauer and susceptibility results indicates that the magnetically ordered states of EuMo6S8 and EuMo6Se8 are strongly affected by the crystal field. 相似文献
996.
Awatsuji Y Tahara T Kaneko A Koyama T Nishio K Ura S Kubota T Matoba O 《Applied optics》2008,47(19):D183-D189
We propose a parallel two-step phase-shifting digital holography technique capable of instantaneous measurement of three-dimensional objects, with a view toward measurement of dynamically moving objects. The technique is based on phase-shifting interferometry. The proposed technique carries out the two-step phase-shifting method at one time and can be optically implemented by using a phase-shifting array device located in the reference beam. The array device has a periodic two-step phase distribution, and its configuration is simplified compared with that required for three-step and four-step parallel phase-shifting digital holographies. Therefore the optical system of the proposed technique is more suitable for the realization of a parallel phase-shifting digital holography system. We conduct both a numerical simulation and a preliminary experiment in the proposed technique. The results of the simulation and the experiment agree well with those of sequential phase-shifting digital holography, and results are superior to those obtained by conventional digital holography using the Fresnel transform alone. Thus the effectiveness of the proposed technique is verified. 相似文献
997.
H. Kubota T. Yamashita Y. Tanaka T. Makita 《International Journal of Thermophysics》1989,10(3):629-637
The vapor pressures of four fluorocarbons have been measured at the following temperature ranges: R123 (2,2-dichloro-l,l,l-trifluoroethane), 273–457 K; R123a (1,2-dichloro-1,1,2-trifluoroethane), 303–458 K; R134a (1,1,1,2-tetrafluoroethane), 253–373 K; and R132b (l,2-dichloro-l,l-difluoroethane), 273–398 K. Determinations of the vapor pressure were carried out by a constant-volume apparatus with an uncertainty of less than 1.0%. The vapor pressures of R123 and R123a are very similar to those of R11 over the whole experimental temperature range, but the vapor pressures of R134a and R132b differ somewhat from those of R12 and R113, respectively, as the temperature increases. The numerical vapor pressure data can be fitted by an empirical equation using the Chebyshev polynomial with a mean deviation of less than 0.3 %. 相似文献
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