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排序方式: 共有1398条查询结果,搜索用时 15 毫秒
121.
W. Shin T. Nakashima M. Nishibori T. Itoh N. Izu I. Matsubara Y. Nakagawa A. Yamamoto H. Obara 《Journal of Electronic Materials》2011,40(5):817-822
The performance of a microcombustor thermoelectric generator device based on a thermopile using p-type Bi0.3Sb1.7Te3 (BST) and n-type Pt films has been investigated. The BST films were prepared by two different methods—pulsed laser deposition (PLD) and
sputter deposition—on Si3N4/SiO2 multilayers on Si substrate. The ceramic catalyst combustor was patterned on the thermopile end on a thin membrane fabricated
by back-side bulk etching of the silicon substrate. At 138°C the thermoelectric power factors of the PLD and sputter-deposited
films were 3.6 × 10−3 W/mK2 and 0.22 × 10−3 W/mK2, respectively. The power from the generator with the sputter-deposited film was 0.343 μW, which was superior to that of the device with the PLD film, which provided 0.1 μW, for combustion of a 200 sccm flow of 3 v/v% hydrogen in air. 相似文献
122.
Masanari Okuno Hideaki Kano Philippe Leproux Vincent Couderc Hiro-o Hamaguchi 《Optical Fiber Technology》2012,18(5):388-393
We describe and characterize a multiplex CARS microspectroscopic system that uses a nanosecond supercontinuum generated from a photonic crystal fiber and a sub-nanosecond pulse laser. This system has a high spectral resolution (<0.1 cm?1) and an ultrabroadband spectral coverage (>2500 cm?1). The estimated spatial resolutions are 0.45 μm (lateral) and 4.5 μm (axial), respectively. This system enables us to obtain CARS spectra and corresponding images in the fingerprint region as well in the CH stretch region. Using this system, we have successfully obtained label-free and multi-mode vibrational images of a yeast cell. 相似文献
123.
Hideaki Araki Yuki Kubo Aya Mikaduki Kazuo Jimbo Win Shwe Maw Hironori Katagiri Makoto Yamazaki Koichiro Oishi Akiko Takeuchi 《Solar Energy Materials & Solar Cells》2009,93(6-7):996-999
Cu2ZnSnS4 (CZTS) thin films were prepared by sulfurizing precursors deposited by electroplating. The precursors (Cu/Sn/Zn stacked layers) were deposited by electroplating sequentially onto Mo-coated glass substrates. Aqueous solutions containing copper sulfate for Cu plating, tin sulfate for Sn plating and zinc sulfate for Zn plating were used as the electrolytes. The precursors were sulfurized by annealing with sulfur at temperatures of 300, 400, 500 and 600 °C in an N2 gas atmosphere. The X-ray diffraction peaks attributable to CZTS were detected in thin films sulfurized at temperatures above 400 °C. A photovoltaic cell using a CZTS thin film produced by sulfurizing an electroplated Sn-rich precursor at 600 °C exhibited an open-circuit voltage of 262 mV, a short-circuit current of 9.85 mA/cm2 and an efficiency of 0.98%. 相似文献
124.
Takao Kume Yoichi Ikeda Takaya Iseki Hisataka Yakabe Hiroyuki Tanaka Hideaki Hikosaka Yasuhiro Takagi Masaya Ito 《International Journal of Hydrogen Energy》2013
We have been developing a hydrogen production module with a Pd-based membrane on catalyst (MOC) from natural gas. The MOC module is expected to be more compact and cheaper than the conventional hydrogen production module. To evaluate the hydrogen production performance of the MOC module and to clear the factor that dominates the effective hydrogen production, we compared the reforming performance of the catalytic support without hydrogen permeable membrane and the MOC module at various reaction conditions. As a result, it was cleared that hydrogen permeation through the membrane improves the methane conversion drastically in the MOC module by comparing with the support only module and changing the experimental conditions. 相似文献
125.
Kazuhiro Kimura Kota Sawada Hideaki Kushima 《Transactions of the Indian Institute of Metals》2010,63(2-3):123-129
Creep deformation properties of creep strength enhanced ferritic steels were investigated. Good linear relationships between creep strain vs. time and creep rate vs. time were observed within a transient stage in a double logarithmic plot. It was appropriately expressed by a power law rather than exponential law, logarithmic law and Blackburn’s equation. With decrease in stress, a magnitude of creep strain at the onset of accelerating creep stage decreased from about 2% in the short-term to less than 1% in the long-term. Life fraction of the time to specific strain of 1% creep strain and 1% total strain, to time to rupture tended to increase with decrease in stress. A time to 1% total strain, that is a parameter for design of high temperature components, was observed in the transient creep stage in the short-term regime, however, it shifted to the accelerating creep stage in the long-term regime. Difference in stress dependence of the minimum creep rate was observed in the high- and low-stress regimes with a boundary condition of 50% of 0.2% offset yield stress. Stress dependence of the minimum creep rate in the high stress regime was equivalent to a strain rate dependence of flow stress observed in tensile test, and a magnitude of stress exponent, n, in the high stress regime decreased with increase in temperature from 20 at 550°C to 10 at 700°C. On the other hand, n value in the low stress regime was about 5, and creep deformation in the low stress regime was considered to be controlled by dislocation climb. 相似文献
126.
127.
128.
H Eisaki H Takagi S Uchida H Matsubara S Suga M Nakamura K Yamaguchi A Misu H Namatame A Fujimori 《Canadian Metallurgical Quarterly》1990,41(10):7188-7191
129.
M Kohsaka N Fukuda R Kobayashi H Honma S Sakakibara E Koyama O Nakano H Matsubara 《Canadian Metallurgical Quarterly》1998,52(2):252-253
Subjective sleep feelings and motor activity were measured in seven healthy elderly subjects for 6 days. The subjects were exposed to bright light (6000 lux) for 30 min in the morning or instructed to sit in front of a desktop lighting device without light. The average level of motor activity during the night was significantly decreased in the bright light condition, compared with the controlled condition. However, daytime motor activity did not show significant differences between the two conditions. From these findings, even a short duration of morning bright light is effective in maintaining sleep without changing daytime activity. 相似文献
130.
Watanabe M. Mukai S. Matsubara K. Yajima H. 《Quantum Electronics, IEEE Journal of》1993,29(12):2855-2858
Cross-coupled-mode operation in a twin-stripe laser is analyzed with particular concern for interstripe gain. When the interstripe gain of a twin-stripe laser is high, cross-coupled-mode operation is obtained with a cavity longer than the coupling length of the twin-stripe waveguide. The far-field pattern is single peaked and deflected to the low carrier density side. These characteristics are in contrast to those of the previous model without interstripe gain 相似文献