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排序方式: 共有493条查询结果,搜索用时 27 毫秒
11.
M. Yoshida H. Ishibashi K. Susa T. Ogura E. Akiba 《Journal of Alloys and Compounds》1995,230(2):100-108
The crystal structure, hydrogen absorbing properties and electrode performance of Laves phase alloy systems, Sc---Zr---Ni---Mn and Sc---Ni---V systems, were studied by optical and scanning electron microscopy, X-ray powder diffraction, pressure-composition isotherm and electrochemical measurements. C14 and C15 Laves phases and minor ScNi-related phase were found in the Sc---Zr---Ni---Mn alloy system. The ScNi-related phase was composed of Sc, Zr and Ni elements. Two kinds of minor phase, BCC and ScNi-related phases, were identified in addition to the C15 phase in the Sc---Zr---Ni---V alloy system. The BCC contained mainly the element V. The ScNi-related phase contributed to an increase in the hydrogen capacity, but those in the V alloy system did not. The multiphase anode with a large amount of the ScNi-related phase showed a low durability against the KOH electrolyte. The substitution of Zr by Sc led to an improvement in the initial activation of the anode, but there was not a clear correlation between the presence of the multiphase in the anode and the rate capability. 相似文献
12.
Abstract. This paper proposes a highly parallel Hough transform algorithm for real-time straight-line extraction and its hardware implementation
on a content-addressable memory (CAM). To achieve high-speed processing, incrementation for voting, which composes the Hough
transform, and calculations for coordinate updating are carried out for the every scan line, not every edge pixel, and extracting
maxima in Hough space is executed by parallel comparing. Moreover, variously weighted voting achieves more accurate line extraction
in spite of the quantization error and noise in the image space. In the implementation, the CAM acts as a PE (processing-element)
array that effectively performs highly parallel processing for the Hough transform and also as a memory for two-dimensional
Hough space, and both voting and peak extraction are directly executed by the CAM. Evaluations of CAM hardware size, processing
time and the accuracy of line extraction show that a real-time and high-resolution Hough transform for a 256256 picture can be achieved using a single CAM chip with current VLSI technology. This CAM-based Hough transform algorithm
promises to be an important step towards the realization of a real-time and compact image-understanding system.
Received: 15 August 1998 / Accepted: 15 March 2000 相似文献
13.
Toshio Ogasawara Yuichi Ishida Takashi Ishikawa Takahira Aoki Toshiyuki Ogura 《Composites Part A》2006,37(12):2236-2240
Helium gas permeability of silicate clay (montmorillonite) particles/epoxy nanocomposites was examined. The incorporation of increasing amounts of montmorillonite particles reduced the helium gas permeability. Based on Fick’s law, gas permeation behavior of the nanocomposite was evaluated. With the increase of montmorillonite loading, gas diffusivity decreased, while gas solubility increased. Helium diffusion behavior is in agreement to the numerical results based on the Hatta–Taya–Eshelby theory. It has been revealed that dispersion of nanoscale platelets in polymer is effective in improving gas barrier property. 相似文献
14.
An InGaAs/InAlAs quantum wire photo-FET has been fabricated on a V-grooved (311) InP substrate by atomic hydrogen assisted molecular beam epitaxy. The room-temperature photosensitivity of the quantum wire photo-FET reached 350 kA/W near a wavelength of 700 nm at a drain-source voltage of 1 V. 相似文献
15.
Shinya Takata Tomo Ogura Eiichi Ide Toshiaki Morita Akio Hirose 《Journal of Electronic Materials》2013,42(3):507-515
The effects of reducing solvents on the bonding process using silver oxide paste in a copper joint were investigated. Three solvent types were tested: diethylene glycol (DEG), triethylene glycol (TEG), and polyethylene glycol (PEG). The strength of the joints was assessed by fracturing, which occurred at the interface of the copper oxide layer and the copper substrate in DEG and TEG samples and at the bonded interface in the PEG sample. Analysis of the samples revealed that, in the DEG and TEG samples, the copper substrate was oxidized during the bonding process, which compromised the shear strength of the joints. In contrast, the PEG sample exhibited nonuniform sintering of the silver layer while retaining good shear strength. It was found that the combination of DEG and PEG produced optimum shear strength in the copper joint, as PEG suppressed the growth of copper oxide and DEG promoted the formation of a dense sintered silver layer. The bonding strength achieved was higher than that of the gold-to-gold joint made using standard Pb-5Sn solder. 相似文献
16.
Michio Tajima Masatoshi Ikebe Yoshio Ohshita Atsushi Ogura 《Journal of Electronic Materials》2010,39(6):747-750
We investigated the effect of Fe contamination on the electronic properties of dislocation clusters in relation to oxygen
precipitation in multicrystalline silicon (mc-Si). Photoluminescence (PL) spectroscopy and mapping were performed at room
and liquid-He temperatures on mc-Si wafers before and after Fe contamination. PL spectra consisted of the band-edge emission,
the 0.78-eV emission associated with oxygen precipitates, and the dislocation-related D-lines. The Fe contamination increased
the electrically active dislocation clusters. Part of these clusters acted as preferential oxygen precipitation sites, and
their electronic properties were not further influenced by the Fe contamination. 相似文献
17.
Hirobumi Shibata Tomoaki Morita Taku Ogura Keishi Nishio Hideki Sakai Masahiko Abe Mutsuyoshi Matsumoto 《Journal of Materials Science》2009,44(10):2541-2547
Mesostructured zirconia particles having monoclinic-type crystalline walls were prepared using a low-temperature crystallization
technique. Crystalline zirconia particles with highly-ordered mesostructures were obtained through the sol–gel process of
zirconium sulfate tetrahydrate at 333 K in the presence of molecular self-assemblies of cetyltrimethylammonium bromide (CTAB)
or mixtures of CTAB and anionic molecules such as sodium dodecyl sulfate and sodium p-toluenesulfonate. Variations in the molar ratios of CTAB and the chemical species of anionic molecules led to the variations
in the periods of highly-ordered zirconia having crystalline walls. Calcination of the mesostructured zirconia particles prepared
using templates consisting solely of CTAB yielded crystalline mesoporous zirconia particles. 相似文献
18.
Kiyoyuki Yambe Hiroki Saito Kazuo Ogura 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(6):614-618
We present a measurement method of the plasma current and density in an atmospheric‐pressure plasma generated using a quartz tube, helium gas, and copper foil electrode by applying a high RF voltage. The plasma in the form of a bullet is released as a plume or jet into the atmosphere. To study the characteristics of the atmospheric‐pressure plasma, the plasma current is measured using a current probe, and the drift velocity of plasma plume is measured using a photodetector. The current of the plasma plume is estimated by subtracting the ground line current from the power line current in the circuit. The density of plasma plume n is estimated from the plasma plume current I and the drift velocity v as I = envS, where S is the cross section of plasma plume. The density of the released plasma into the atmosphere is estimated as ∼1018 m−3 by the method. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
19.
Isamu Ogura Mari Kotake Hiromu Sakurai Kazumasa Honda 《Aerosol science and technology》2016,50(8):846-856
The flat surface of Nuclepore filters is suitable for observing collected particles with a scanning electron microscope (SEM). However, experimental data on surface-collection efficiency are limited because surface-collection efficiencies cannot be measured directly using aerosol measuring instruments. In this study, the surface-collection efficiencies of Nuclepore filters were determined by establishing the ratio of the number of particles deposited on the surface of the filter visually counted with an SEM to the number of inflow particles counted by a condensation particle counter, using monodispersed polystyrene latex particles (30–800 nm) and silver particles (15–30 nm). Because Nuclepore filters with smaller pore sizes would be expected to produce higher minimum surface-collection efficiency and a higher pressure-drop, 0.08 and 0.2 µm Nuclepore filters were chosen as the test filters in view of both collection efficiency and pressure drop. The results showed that the minimum surface-collection efficiencies of the 0.08 µm pores at face velocities of 1.9 and 8.4 cm·s?1 were approximately 0.6 and 0.7, respectively, and those of the 0.2 µm pores at face velocities of 1.5 and 8.6 cm·s?1 were approximately 0.8 and 0.6, respectively. Because the pressure drop of the 0.2 µm pore filter was lower than that of the 0.08 µm pore filter under the same flow-rate conditions, the 0.2 µm pore filter would be more suitable considering the pressure drop and collection efficiency. The obtained surface collection efficiencies were quantitatively inconsistent with theoretical surface-collection efficiencies calculated using conventional theoretical models developed to determine the collection efficiency of filters with larger pores.© 2016 American Association for Aerosol Research 相似文献
20.
Tomah Sogabe Akio Ogura Mitsuyoshi Ohba Yoshitaka Okada 《Progress in Photovoltaics: Research and Applications》2015,23(1):37-48
Spectral response of multi‐junction solar cell is complicated because of the interplay between external measurement conditions such as bias light intensity, monochromatic light intensity, bias voltage, and intrinsic electrical properties of series interconnected subcells. In this paper, we report an experimental study on the bias voltage‐dependent spectral response (SR) for multi‐junction solar cell. A self‐consistent iteration loop was developed from a nonlinear least square Powell hybrid algorithm that was used for curve fitting the experimental SR versus bias voltage data of each subcell. We demonstrated for the first time that this approach enabled us to derive the electrical parameters such as dark saturation currents (J0), shunt resistance (Rsh), series resistance (Rs), and spectra response (Jphoto) for each subcell of a Ga0.99In0.01As/Ge dual junction solar cell with stable convergence. The accuracies of the fitting results were confirmed by the agreement between the J–V curves calculated on the basis of these parameters and the experimental J–V curve of multi‐junction solar cell measured under AM1.5 and 1 sun condition. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献