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81.
Mizuno Makoto Imai Satoshi Tsukada Minoru Hida Eiki Naka Ken-Ichi 《IEEE transactions on bio-medical engineering》1985,(1):56-60
A microcomputer system was developed to measure visual spatiotemporal receptive fields. The system performs three functions: 1) generation of a binary spatiotemporal white-noise stimulus, 2) acquisition of spike discharges from retinal ganglion cells, and 3) extraction of the linear part of the spatiotemporal receptive flelds by cross correlating the input against the output. We have applied this system to the measurement of the spatiotemporal receptive fields of cat and catfish retinal ganglion cells. 相似文献
82.
Rong-Jun Xie Naoto Hirosaki Mamoru Mitomo Takayuki Suehiro Xin Xu Hidehiko Tanaka 《Journal of the American Ceramic Society》2005,88(10):2883-2888
Rare-earth-doped Ca-α-SiAlON phosphors, with the compositions of (Ca1−3/2 x RE x ) m /2 Si12− m − n Al m+n O n N16− n (RE=Ce, Sm, and Dy, 0.5≤ m =2 n ≤3.0), were prepared by sintering at 1700°C for 2 h under 10 atm N2 . The concentration of rare earths varied from 3 to 30 at.% with respect to Ca. The photoluminescence (PL) properties were investigated as functions of the composition of the host matrix (i.e., m ) and the concentration of rare earths (i.e., x ). The results show that the emission properties can be optimized by tailoring m and x . The Ce3+ luminescence originating from the 4 f –5 d interconfigurational transitions is greatly affected by the environment surrounding the Ce3+ ions, which differs from the Sm3+ or Dy3+ luminescence arising from the 4 f –4 f intraconfigurational transitions. X-ray diffraction and scanning electron microscopy were used to explain the composition and concentration dependence of PL properties. 相似文献
83.
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85.
Chie Ando Toshimasa Suzuki Youichi Mizuno Hiroshi Kishi Sayuri Nakayama Mamoru Senna 《Journal of Materials Science》2008,43(18):6182-6192
In an attempt to obtain finest possible microparticles of BaTiO3 (BT) with highest possible tetragonality via a solid state route, starting mixtures comprising BaCO3 and TiO2 were subjected to various pretreatments including addition of glycine and mechanical activation. Reaction processes were
monitored by the changes in the weight, crystallinity, and morphology in detail. While mechanical activation with glycine
significantly increased the rate of reaction and homogeneity of the particle size of the product, BT, simultaneous particle
growth of BT was intolerably acute for micro-electronic devices. The fast particle coarsening was predominated by the coalescence
of BT tiny particles formed around titania. A mixture with higher homogeneity was attained by using finer starting materials
under wet mixing, avoiding significant mechanical stressing. Particle growth of BT was suppressed to ca. 100 nm to obtain
fully crystallized BT particles without significant loss of tetragonality and, hence, close to meet our requirements for MLCCs. 相似文献
86.
Okumoto M. Rajanikanth S. Katsura S. Mizuno A. 《Industry Applications, IEEE Transactions on》1998,34(5):940-944
Direct methanol synthesis from CH4 and O2 has been experimentally studied using pulsed discharge plasma in concentric-cylinder-type reactors. The methanol production becomes efficient with an increase in the average electric field strength of the reactor. A combination of the pulsed discharge and catalysts was tested and was proved to be effective in increasing both the production and selectivity of methanol. In the present stage, about 2% of CH4 can be converted into other hydrocarbons, and a methanol yield of around 0.5% and selectivity of 38% can be obtained when a catalyst of V2O5+SiO2 is combined with the pulsed discharge plasma 相似文献
87.
We have experimentally studied the high-lateral-field carrier velocity near the source edge in sub-0.1 μm MOSFETs. It is demonstrated that the high-field electron velocity and hole velocity have universal low-field mobility dependence. This shows that the hole velocity is lower than the electron velocity due to the hole's lower mobility. Moreover, we have investigated the low-power CMOS operation using the velocity overshoot. It is verified that there is a most suitable supply voltage for improving the CMOS operation using velocity overshoot. The most suitable supply voltage is shown to be about 1 V. Therefore, the velocity overshoot will be very useful for low voltage CMOS operation in the future 相似文献
88.
Conditions for synthesizing acicular fine particles of goethite with high aspect ratio were devised by oxidizing mixed slurry
comprising ferrous carbonate and hydroxide after neutralizing by alkali carbonate. By bubbling N2 after neutralization into the slurry containing FeCO3 and Fe(OH)2, dissolved CO2 is ejected. As a consequence, the relative concentration of CO32− decreases and that of hydroxide increases. These favor the increase of the aspect ratio of the goethite particles via two
factors, i.e., (1) decrease in the critical size of the nuclei and (2) suppression of growth inhibition at the tip of needle-like
particles due to CO32− adsorption. We propose a reaction scheme for the entire processing. 相似文献
89.
A district heating and cooling system (DHC) is expected to be a promising energy-saving measure for high-density business areas in Japan. However, it has not been verified what advantages of the DHC are important for energy conservation. The clarification of this issue is supposed to contribute to improving the energy efficiency of the DHC. 相似文献
90.
Jungo Kondo Aoki K. Kondo A. Ejiri T. Iwata Y. Hamajima A. Mori T. Mizuno Y. Imaeda M. Kozuka Y. Mitomi O. Minakata M. 《Photonics Technology Letters, IEEE》2005,17(10):2077-2079
We present a novel thin-sheet X-cut LiNbO/sub 3/ optical modulator structure which can be fabricated by precise polishing and lapping to obtain a thinner LiNbO/sub 3/ substrate for a lower driving voltage in addition to velocity matching and impedance matching. We demonstrated that the fabricated modulator had a driving voltage V/spl pi/ of 2 V and zero chirp for 40-Gb/s operation and had a high potential for suppressed dc drift, and long-term reliability. 相似文献