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71.
A magnetic vortex core in a ferromagnetic circular nanodot has a resonance frequency originating from the confinement of the vortex core. By the micromagnetic simulation including the spin-transfer torque, we show that the vortex core can be resonantly excited by an ac (spin-polarized) current through the dot and that the resonance frequency can be tuned by the dot shape. The resistance measurement under the ac current successfully detects the resonance at the frequency consistent with the simulation. 相似文献
72.
Abstract It was investigated that, when an Al evaporated layer on a GaP (GaAs, GaAs1?y P y ) substrate was bombarded with total fluences of 0.1?1.0 × 1018 electrons cm?2 at 7 MeV and at 50°C, a thin heteroepitaxial layer of Al x Ga1?x P (Al x Ga1?x As, Al x Ga1?x As1?y P y ) crystal was grown on S-doped (111), (100) and (110) GaP [(110) Cr, O-doped GaAs, (100) Te-doped GaAS1?y P y ] substrates. Evidence for the creation of the epilayers before annealing was obtained from measurements using an X-ray diffractometer, an X-ray photoelectron spectrometer, a reflection high-energy electron diffractometer, a transmission electron microscope and a scanning transmission electron microscope. In the case of Al/GaP, the epitaxial layers of Al~0.25Ga~0.75P, Al~0.5Ga~0.5P and Al~0.75Ga~0.25P were grown on (111), (100) and (110) GaP substrates, respectively. Their compositions did not vary with the total electron fluence. 相似文献
73.
Toshiaki Yamaguchi Sota Shimizu Toshio Suzuki Yoshinobu Fujishiro Masanobu Awano 《Electrochemistry communications》2008,10(9):7656-1383
A high performance small-scale solid oxide fuel cell supported by a microtubular cathode was successfully developed via the extrusion of a (La0.8Sr0.2)0.97MnO3 cathode support and subsequent surface coating with a (La0.8Sr0.2)0.97MnO3–Ce0.9Gd0.1O1.95 activation layer followed by Sc2O3-doped ZrO2 electrolyte and NiO–Ce0.9Gd0.1O1.95 anode slurries. The cell was electrochemically evaluated in a humidified hydrogen (3% H2O) atmosphere, and exhibited a stable open circuit voltage above 1.05 V in the temperature range from 550 to 750 °C. Maximum power densities of 46.5, 163.2 and 452.8 mW cm−2 were generated at 550, 650 and 750 °C, respectively. The results indicate the realization of a stable and high performance cathode-supported micro SOFC. 相似文献
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Daisuke Onoshima Noritada Kaji Manabu Tokeshi Yoshinobu Baba 《Analytical sciences》2008,24(2):181-183
We have developed a fluorescence resonance energy transfer (FRET) probe based on the conjugation of a quantum dot (QD) with dye (YOYO-3) intercalated DNA. The FRET-inducing electrostatic coupling of DNA and the QD made structural changes to the QD-DNA conjugates, which significantly prevented an enzymatic reaction between the DNA and a conventional restriction endonuclease (EcoRI). 相似文献
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Takashi Uemura Nobuyuki Okuda Hiroya Kirmura Yasuko Okuda Yoshinobu Ueba Tuguru Shirakawa 《先进技术聚合物》1997,8(7):437-442
Electroluminescent(EL) devices have been fabricated using four different polymers with different glass transition temperatures (Tg) dispersed with N,N′-bis-(3-methylphenyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (TPD) as a hole transport layer and tris(8-hydroxyquinoline) aluminum (Alq3) as an emitting layer. It was found that the higher the Tg of the polymer, the longer the lifetime of the device. From observations of TPD-doped polymer films with optical microscope and atomic force microscope, dispersing TPD in the polymers was found to suppress the crystallization that causes the roughness of the film surface. It was also observed that the higher the Tg of the host polymers, the more difficult TPD crystallization was. The property of the EL device with polyethersulfone (PES) dispersed with TPD was also investigated. The lifetime of EL device with the TPD doped PES film was improved more than five times at a current density below 10 mA/cm2 compared with the device with a conventional TPD hole transport layer. © 1997 John Wiley & Sons, Ltd. 相似文献
79.
Hyoe Hatakeyama Takanori Yoshida Yoshinobu Izuta Shigeo Hirose Tatsuko Hatakeyama 《Macromolecular Symposia》1999,144(1):313-321
Cellulose-based polycaprolactone (CAPCL) sheets were prepared from cellulose acetate (CA) and ϵ-caprolactone (CL). Thermal properties of the obtained CAPCL's were studied by differential scanning calorimetry (DSC), thermogravimetry (TG) and TG-Fourier transform infrared spectrometry (TG-FTIR). The glass transition temperatures (Tg 's) of CAPCL decreased with increasing CL/OH ratio, until CL/OH ratio reached 15 and then increased above that ratio. Melting of CAPCL was observed when CL/OH ratio was over 10. The thermal degradation temperatures (Td 's) of CAPCL increased from ca. 350 °C to 390 °C with increasing CL/OH ratio. The results obtained by TG-FTIR analysis of CAPCL showed that gases with OH, CH, C=O, C-O-C groups evolved by thermal degradation. 相似文献
80.