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41.
Satoru Maegawa Takao Mizusaki Yutaka Hirayoshi Tadashi Kusumoto Akira Hirai 《Journal of Low Temperature Physics》1980,39(1-2):151-171
Nuclear spin-lattice relaxation properties of hcp solid 3He with 4He impurities have been studied. At temperatures below the exchange plateau region, three kinds of relaxation time were observed. To analyze the data, a phenomenological four-bath model was developed, the four baths being the Zeeman bath, the phonon bath, an X-bath, and a Y-bath. The X-bath consists of the exchange bath and a part of the 4He-4He elastic interaction bath. The Y-bath is the main part of the elastic interaction bath. We measured the concentration dependence of the energy constants of all the baths, as well as the temperature and concentration dependences of the three kinds of relaxation time. The relaxation behavior corresponding to the process between the X-bath and the Y-bath could not be expressed by a single exponential function of time and the relaxation rate was strongly dependent on the concentration. This process may be related to the internal thermal equilibrium process within the elastic interaction bath. The impurity-dependent relaxation time between the X-bath and the phonon bath had a temperature dependence of T
–n with n = 7.4±0.3. 相似文献
42.
Fujiyoshi T. Shiratake S. Nomura S. Nishikawa T. Kitasho Y. Arakida H. Okuda Y. Tsuboi Y. Hamada M. Hara H. Fujita T. Hatori F. Shimazawa T. Yahagi K. Takeda H. Murakata M. Minami F. Kawabe N. Kitahara T. Seta K. Takahashi M. Oowaki Y. Furuyama T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):54-62
A single-chip H.264 and MPEG-4 audio-visual LSI for mobile applications including terrestrial digital broadcasting system (ISDB-T / DVB-H) with a module-wise, dynamic voltage/frequency scaling architecture is presented for the first time. This LSI can keep operating even during the voltage/frequency transition, so there is no performance overhead. It is realized through a dynamic deskewing system and an on-chip voltage regulator with slew rate control. By the combination with traditional low power techniques such as embedded DRAM and clock gating, it consumes only 63 mW in decoding QVGA H.264 video at 15 frames/sec and MPEG-4 AAC LC audio simultaneously. 相似文献
43.
Jun Koyanagi Hideo Nagayama Satoru Yoneyama Takahira Aoki 《Mechanics of Time-Dependent Materials》2016,20(2):219-232
This paper presents the time dependence of the mesoscopic strain of a triaxial woven carbon-fiber-reinforced polymer under creep loading measured using digital image correlation (DIC). Two types of DIC techniques were employed for the measurement: conventional subset DIC and mesh DIC. Static tensile and creep tests were carried out, and the time dependence of the mesoscopic strain distribution was investigated by applying these techniques. The ultimate failure of this material is dominated by inter-bundle decohesion caused by relative rigid rotation and relating shear stress. Therefore, these were focused on in the present study. During the creep tests, the fiber directional strain, shear strain, and rotation were monitored using the DIC, and the mechanism for the increase in the specimen’s macro-strain over time was investigated based on the results obtained by the DIC measurement. 相似文献
44.
Satoru Okamoto 《机械工程与自动化:英文版》2014,(10):770-780
The tendency for air column resonance generation in structures with a constant volume behind a tube array like that of an exhaust gas economizer has been reported, but many points remain unclear with respect to the mechanism and conditions that generate acoustical resonance. When acoustical resonance is generated, in reality, prevention and suppression measures are implemented by inserting a baffle plate into the ducts through a process of trial and error. The purpose of this study is to clarify the mechanism of generation of acoustical resonance, and to establish an appropriate measure to prevent such resonance. Noise generated in an exhaust gas economizer was correlated with the flow inside the tube array and experimentally analyzed, and the mechanism for resonance generation was considered. In addition, the effectiveness of a baffle plate positioned in order to prevent resonance was investigated. We have successfully employed a single baffle plate to suppress resonance. 相似文献
45.
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47.
Isao Tsuyumoto Yuya Nakakura Satoru Yamaki 《Journal of the American Ceramic Society》2014,97(11):3374-3377
Nanosized‐layered rock‐salt LiVO2 was prepared by a new method from peroxo‐polyvanadic acid. The X‐ray diffraction pattern was well fitted with the space group R?3m in the Rietveld analysis and the crystallite size was estimated at 47 nm. The electrochemical properties as cathode materials for lithium ion batteries were investigated. The specific capacity of LiVO2 was greatly improved to 149 mAh/g under the current density of 149 mA/g, in comparison with that of the conventional LiVO2 below 50 mAh/g prepared by the solid‐state reactions. 相似文献
48.
Ag nanoporous structure has been fabricated by dealloying of Al–20 at.%Ag in 2 M HCl at room temperature. We describe the changes of phase constitution and microstructural morphology during the dealloying. The bi-phase structure of α-Al and γ-Ag2Al was obtained using melt-spinning, and considerable amount of γ-Ag2Al was suppressed. According to the phase quantitative analysis, 5.6 % γ-Ag2Al was precipitated at the grain boundary and inside the grain. At the early stage of dealloying process, the deep channel occurred at the interface of α-Al and γ-Ag2Al due to concentration gradient of Ag; and then, α-Al was preferentially dealloyed with comparison to γ-Ag2Al and formed 3-dimensional nanoporous structure which showed the open-pore/ligament bi-continuous structure. After 720 min, γ-Ag2Al was dealloyed and formed 2-dimensional pored-wall structure. At the end of dealloying reaction, the initial grain/intermetallic wall structure was maintained. The Ag nanoporous structure was gradually coarsened with the increase of dealloying time, from 25 ± 5 nm at 20 min to 113 ± 22 nm at 720 min. The calculated coefficient of surface diffusion of Ag was 2.34 × 10?17 m2/s. The surface diffusivity of Ag obtained in this study showed two orders of magnitude higher than the Au dealloyed from Au–Ag precursor at the similar temperature. 相似文献
49.
Boron and nitrogen-incorporated graphene thin films were grown on polycrystalline Ni substrates by thermal chemical vapor deposition using separate boron- and nitrogen-containing feedstocks. Boron and nitrogen atoms were incorporated in the film in almost equal amounts and the total content reached ∼28%. The film predominantly consisted of separate graphene and boron nitride domains. Carrier concentration in the graphene domains was estimated to be about 1 × 10−3 e/atom (3.8 × 1012 cm−2) from G band shift in Raman spectra. 相似文献
50.
Satoshi?KameokaEmail author Satoru?Wakabayashi Eiji?Abe An?Pang?Tsai 《Catalysis Letters》2016,146(7):1309-1316