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81.
Yuta Nabatame Tsuyoshi Matsumoto Yuki Ichige Takashi Komine Ryuji Sugita Masayuki Murata Yasuhiro Hasegawa 《Journal of Electronic Materials》2013,42(7):2172-2177
In this study, we have numerically analyzed the transport properties of Bi-Sb nanowires, taking into account wire boundary scattering. Wire boundary scattering slightly decreased the Seebeck coefficient of Bi-Sb nanowires. This effect is due to the observation that boundary scattering and the mobility ratio of L-point electrons to T-point holes in the nanowires are smaller than those in bulk Bi-Sb because the wire boundary scattering suppresses the mobilities of L-point electrons and heavy holes. The largest Seebeck coefficient for all wire diameters was obtained when the Sb concentration was 5 at.%. The effective mass approached zero near 5 at.% Sb, and the small effective mass led to a large subband shift in each band. Thus, a small effective mass enhances the quantum effect at a fixed wire diameter, even if wire boundary scattering is taken into account. 相似文献
82.
83.
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85.
Tsuyoshi Nishiwaki Atsushi Yokoyama Zen-ichiro Maekawa Hiroyuki Hamada 《Composite Structures》1995,32(1-4):635-640
Localized impact problems for composite structures have recently become important. In this study, some elastic wave velocities in 7-ply GFRP laminate with [02/903/02] ply orientation after low speed impact was investigated by using both experimental methods and finite element methods. For the finite element simulation, the quasi-three-dimensional model was used. Comparing the results, the validity for the application of this model to the dynamic problem was estimated. Moreover the quasi-three-dimensional model is applied to the GFRP plates with interlaminar delamination. The relationship between the elastic wave velocities and delaminated states is discussed. 相似文献
86.
Jun Sawai Tsuyoshi Nakai † Atsushi Hashimoto & Masaru Shimizu 《International Journal of Food Science & Technology》2004,39(9):967-974
The apparent reaction rate constants (k) of the reaction that generates reducing sugar (presented as mg maltose equivalents) from raw sweet potato starch by using β‐amylase were determined by varying enzyme concentration, starch concentration and pH. The Arrhenius plot of the k‐value reached a peak at approximately 86 °C; the activation energy and frequency factor were also determined. Moreover, the amount of reducing sugar produced in sweet potato heated by infrared irradiation was estimated by using the values of k and the kinetic parameters. The calculated amounts of reducing sugar produced generally agreed with the experimental values. These results indicate that the amount of reducing sugar produced in heat‐treated sweet potato can be predicted by the methodology described in this study. 相似文献
87.
Masahiko Yamada Shoichiro Fukusako Tsuyoshi Kawanami 《International Journal of Refrigeration》2002,25(2)
For the purpose of determining the optimum operation condition of liquid-ice thermal storage system, the performance analysis has been carried out. The target system was consisted of refrigerator, its auxiliary devices, liquid-ice production device, piping system, and thermal load section. The system performances were widely investigated analytically for the variety of operation conditions including the cycle performance of a refrigerator. The optimum operation condition of the liquid-ice thermal storage system from the viewpoint of coefficient of performance and the performance of heat release were discussed. 相似文献
88.
Hidero Unuma Koh Miura Tsuyoshi Furusaki Kohei Kodaira 《Journal of the American Ceramic Society》1991,74(6):1291-1295
Crystallization of Li-Al-Si-O-N oxynitride glasses based on the β-spodumene composition and the properties of the resultant glass-ceramics have been studied. The onset of the precipitation of metastable high-quartz solid solution and its transformation to β-spodumene shift to higher temperatures with increasing nitrogen content of the oxynitride glasses. Nitrided glass-ceramics crystallized at 1200°C have negative thermal expansion coefficients, since high-quartz structure is maintained up to 1000° and 1200°C. Knoop hardness and density of the glass-ceramics increase with increasing nitrogen content. There was evidence that part of the nitrogen atoms were incorporated into the high-quartz solid-solution structure and that a small amount of the minor phase of Si2 N2 O was precipitated in highly nitrided glass-ceramics. 相似文献
89.
90.
Tsuyoshi Saotome Hansang Kim David Lashmore H. Thomas Hahn 《Bulletin of Materials Science》2011,34(4):615-622
We describe in this paper a transparent conducting film (TCF). It is a fibrous layer of multiwalled carbon nanotubes (MWNTs),
labeled a dilute CNT mat, that was prepared and unidirectionally stretched to improve both the optical and electrical properties.
After stretching by 80% strain, transmittance at 550 nm wavelength was improved by 37% and sheet resistance was reduced to
71% of the original value. The improvement of the transmittance can be explained by increased area of the CNT mat after stretch,
and the reduced sheet resistance can be explained by increased density of the CNT alignment in lateral direction due to contraction.
Based on the microscopic observation before and after stretch, models to describe the phenomena are proposed. By further expanding
on this method, it may be possible to obtain a transparent conducting carbon nanotube film which is crack-resistant for solar
cell applications. 相似文献