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141.
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Mito I. Kitamura M. Kaede K. Odagiri Y. Seki M. Sugimoto M. Kobayashi K. 《Electronics letters》1982,18(1):2-3
Using a new LPE growth technique, an InGaAsP/InP planar buried heterostructure laser diode (PBH-LD) has been realised in 1.3 and 1.5 ?m wavelength regions. As a result of the effective carrier confinement, CW threshold currents as low as 8.5 mA and 13 mA have been obtained in 1.3 and 1.5 ?m PHB-LDs, respectively, at room temperature. 相似文献
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146.
Sugimoto Y. Torikai T. Makita K. Ishihara H. Minemura K. Taguchi K. Iwakami T. 《Electronics letters》1984,20(16):653-654
Planar-structure InP/InGaAsP/InGaAs avalanche photo-diodes have been realised by using a VPE-growth technique and a Be+ implanted guard ring. Sensitivity measurement has been performed at 1.3 ?m and 1.8 Gbit/s. The minimum average received level required for 10?9 BER was ?31.3 dBm, which was 1.2 dB better than the value for the Ge-APD. 相似文献
147.
T. Inagaki Y. Doi H. Hirabayashi Y. Kato K. Kawano H. Sato S. Sugimoto K. Takamatsu E. Takasaki T. Tsuru H. Yoshimura O. Asai T. Satow 《低温学》1984,24(2):83-89
Benkei, which was a large window frame conventional magnet at KEK has been converted to a superconducting magnet. In the conversion, the pole gap has been doubled from 0.5 m to 1.0 m retaining an analysing power at 2 T m. Several new techniques were applied to coil windings and cryostat fabrication. The superconducting Benkei has shown satisfactory performances for long term operation. 相似文献
148.
Addition of [FeII(MeCN)24+(ClO−4)2 to solutions of hydrogen peroxide in dry acetonitrile (MeCN) catalyzes a rapid disproportionation of H2O2 via the initial formation of an adduct, [FeII(HOOH)↔Fe(O)(OH2)]2+, which oxidizes a second H2O2 to dioxygen. This intermediate also cleanly oxidizes substituted hydrazines, alcohols, aldehydes, and thioethers by a two-electron process. The products for these H2O2 oxidations are consistent with those that result from catalase- and some peroxidase-catalyzed processes. In the same aprotic medium (MeCN) anhydrous FeIIICl3 catalyzes the demethylation of N,N-dimethylaniline, the epoxidation of olefins, and the oxidative cleavage of 1-phenyl-1,2-ethanediol (and other 1,2-diols) by hydrogen peroxide. A mechanism is proposed in which an initial Lewis acid-base interaction of FeIIICl3 with H2O2 generates a highly electrophilic FeIII-oxene species as the reactive intermediate. For each class of substrate the products closely parallel those that result from their enzymatic oxidation by cytochrome P-450. Because of (a) the close congruence of products, (b) the catalytic nature of the FeIIICl3/H2O2 reaction mimic, and (c) the similarity of the dipolar aprotic solvent (acetonitrile) to the proteinaceous lipid matrix of the biomembrane, the form of the reactive intermediate may be the same in each case. This is in contrast to the prevailing view that cytochrome P-450 acts as a redox catalyst to generate an Fe(V)-oxo species or an Fe(IV)-oxo cation radical as the reactive intermediate. 相似文献
149.
To assess the frictional properties at the wedge of a toroidal field coil of a tokamak fusion reactor, friction tests were conducted using structural steel, JN2, against various materials in a vacuum at low temperatures under a normal load of 10 N and a peak-to-peak sliding amplitude of 100 μm. The temperature was mainly ≈ 5 K and the ambient pressure ≈ 10−3 Pa. The relationship between the frictional characteristics and the number of cycles depends on both the material combination and temperature. Two typical patterns of behaviour were observed at 5 K depending on the combination; fairly constant friction and very high and fluctuating friction. The high friction was caused by severe adhesion between surfaces. Temperature dependence of friction was also observed for JN2-copper. 相似文献
150.
Kosaka H. Kurihara K. Uemura A. Yoshikawa T. Ogura I. Numai T. Sugimoto M. Kasahara K. 《Photonics Technology Letters, IEEE》1994,6(3):323-325
Vertical-to-surface transmission electrophotonic devices with a vertical-cavity are described. The individually accessed 12×4 arrays are characterized and demonstrated to have uniform room-temperature continuous-wave operating characteristics for a threshold current of ~2.8±0.15 mA and a slope efficiency of ~0.18±0.012 W/A with a single transverse mode. Both low threshold and high efficiency with 5% and 7% deviation, respectively, are achieved simultaneously. These devices can be used to constructing two-dimensional massively parallel optical interconnections 相似文献