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81.
Masakazu Katsuno Noboru Ohtani Tatsuo Fujimoto Hirokatsu Yashiro 《Journal of Electronic Materials》2005,34(1):91-95
The effect of off-orientation growth has been investigated in terms of stacking fault formation during physical vapor transport
(PVT) growth of silicon carbide (SiC) single crystals on the (11
0) seed crystal surface. Occurrence of stacking fault formation is largely dependent on the direction of off-orientation,
and basal plane stacking fault density is significantly reduced by growing the crystals on a (11
0) seed crystal off-oriented toward 〈0001〉. The density of the basal plane stacking faults rapidly decreases from 100–150
cm−1 to ∼10 cm−1 as the degree of off-orientation is increased from 0 to 10 deg. The results are interpreted in the framework of microscopic
facet formation during PVT growth, and the introduction of off-orientation of seed crystal is assumed to prevent (01
0) and (10
0) microfacet formation on the (11
0) growing surface through modification of the surface growth kinetics and to suppress the stacking fault formation.
An erratum to this article is available at . 相似文献
82.
An in-line type compact micropulse lidar (MPL) with an annular beam was developed for low-altitude cloud measurement. An optical circulator and a couple of axicon prisms for an annular beam were installed on the lidar optics. The advantage of using the in-line MPL is its ability to obtain a near-range measurement with a narrow field of view of 0.1 mrad and to obtain a depolarization measurement of the orthogonally polarized echoes caused by ice crystals of a low-altitude cloud. The total insertion loss of the lidar optics was 3 dB. Detectors such as avalance photodiode detectors can be operated in an analog mode near the breakdown voltage because of the high isolation of the optical circulator. The ideal lidar echo variation from the nearest distance was verified by measuring the mountain echoes at various distances. The depolarization measurement of a low-altitude ice cloud was also demonstrated. 相似文献
83.
A series of boroxine polymers (BP) with different backbone lengths were synthesized. Polymer electrolytes prepared by blending poly(ethylene oxide) (PEO) and BP with Li(N(SO 2CF3)2) (LiTFSI) were evaluated. Better performance was observed by addition of BP in the PEO based polymer electrolyte. The effect of the backbone length of BP on electrochemical properties of PEO–BP–LiTFSI electrolyte systems was investigated. Compared with the PEO–LiTFSI system, about five times higher ionic conductivity at low temperature and five times higher lithium ion transference number at 70°C were achieved by incorporation of long chain BP in the electrolyte. Short chain BP exhibited outstanding performance in decreasing interfacial resistances on both anode and cathode surfaces. Good battery performance was also observed for these BP containing hybrid polymer electrolytes. 相似文献
84.
Tatsuo Tashiro 《应用聚合物科学杂志》1974,18(10):2903-2916
Hydrolysis resistance and mechanism of reaction products of hydroxymethylated 2-substituted (X) 4,6-diamino-s-triazines (MXT) with cotton fabrics has been studied. Finishing reagents used were MXT having the following substituents: X = CH3O? (MMT), (CH3)2CHO? (MIPT), CH3? (MAG), C2H5NH? (MEM), HOC2H4NH? (MHEM), and (HOC2H4)2N? (MBHEM). For comparison, trimethylolmelamine (TMM), dimethylolurea (DMU), dimethylolethyleneurea (DMEU), and dimethylol-ethyltriazone (DMET) were used. Hydrolysis was carried out in buffer and NaOH solutions of various pH's for 30 min at 80°C. The order of hydrolysis resistance of crosslinked reagents was determined from the nitrogen contents retained. It was as follows: pH 1, MROT < MRNT < MRT; pH ≧ 2, MROT > MRT > MRNT; pH ≦ 13, MROT > MRNT; pH 14, MROT < MRT < MRNT, where MROT is hydroxymethylated 2-alkoxy (MMT, MIPT), MRT is hydroxymethylated 2-alkyl (MAG), and MRNT is hydroxymethylated 2-alkylamino-4,6-diamino-s-triazine (MEM, MHEM, MBHEM). This fact can be explained in terms of the basicity constant (pKb) of crosslinked MXT with cotton (approximately pKb) of 2-substituted 4,6-diamino-s-triazine (XT). The hydrolysis rates of crosslinked MMT, MAG, and MEM were determined at pH 2. The activation energies were 21.8 for MMT, 20.9 for MAG, and 21.0 kcal/mole for MEM. 相似文献
85.
86.
87.
Lorenz-Peter Schmidt Tatsuo Itoh 《Journal of Infrared, Millimeter and Terahertz Waves》1981,2(3):427-436
Generalized fin-lines are analyzed which consist of slots located on more than one interface between dielectric layers inserted in parallel with the E-plane of a waveguide. The analysis is based on a simplified formulation technique based on the spectral domain immittance matrix followed by a Galerkin's method. It allows as many slots as one desires at each interface, and the locations and the widths of these slots are arbitrary. The numerical process to carry out the present analysis is rather efficient. Some numerical data, including propagation constants of the propagating modes as well as characteristic impedances are presented for several structures considered useful for millimeter-wave circuit applications. 相似文献
88.
D. B. Marshall Tatsuo Noma A. G. Evans 《Journal of the American Ceramic Society》1982,65(10):c175-c176
A simple indentation technique for measuring the hardness-to-modulus ratio of elastic/plastic materials was developed. The method, which is based on measurement of the elastic recovery of the in-surface dimensions of a Knoop indentation, allows ready evaluation of the hardness-to-modulus ratio to an accuracy better than 10%. 相似文献
89.
Bukhari Abdul R. S. Narumi Jun Suma Kozo Togawa Tatsuo 《IEEE transactions on bio-medical engineering》1982,(5):359-361
The sequence of excitation of cardiac muscles is greatly affected by any abnormality in the conduction system of the heart. Epicardial mapping for the measurement of activation time at different points is helpful for the diagnosis of such abnormalities. For the measurement of activation time at different points of the epicardial surface, a number of sophisticated instruments, including microcomputer-based ones, have been reported. However, the need for a reliable, low-cost, and easy to operate instrument cannot be denied. In this note, such a cardiac arrival time analyzer is described. 相似文献
90.
Satoshi Matsumoto Tatsuo Kawamura 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(1):97-101
As the higher impulse testing voltage, residual inductance of the test circuit or the stray capacitance of the test object increases with size. This means that the overshoot superposed on standard lightning impulse voltage would not be neglected because of its larger value during the lightning test. This paper describes the analysis of overshoot and oscillation based on the equivalent circuit containing a residual inductance. The waveform parameters such as relative overshoot magnitude, oscillation frequency are also derived to evaluate the influence of the residual inductance in the impulse testing circuit. The oscillating impulse waveform is related to the base curve of the standard lightning impulse. Furthermore, the base curve for oscillating impulse is proposed by the analysis. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献