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91.
A design for composite-channel structures consisting of an InGaAs channel and an InP subchannel for use as heterostructure field-effect transistors is presented for the first time. This novel channel structure takes advantage of both the high drift velocity and low impact ionization of InP at high electric fields as well as the high electron mobility of InGaAs at low electric fields. It is shown that the doping density of the InP subchannel is the key parameter to realize the advantages of the composite channel. A very high transconductance of 1.29 S/mm and a current gain cutoff frequency of 68.7 GHz are achieved with 0.6 and 0.7 /spl mu/m gates, respectively. The average velocity of electrons in the composite channel is 2.9/spl times/10/sup 7/ cm/s. The devices have no kink phenomena in their I-V characteristics possibly due to low impact ionization in the InP subchannel.<> 相似文献
92.
The noise characteristics of semiconductor laser amplifiers (SLAs) in the Ga1-xInxAs/GaInAsP/InP strained quantum well (QW) system are theoretically calculated and analyzed using density-matrix theory and taking into account the effects of band mixing on both the valence subbands and the transition dipole moments. The numerical results show that a reduced noise figure can be obtained in both tensile and compressively strained QW structures due to the increase in differential gain and the decrease in transparent carrier density. From a comparison among compressively strained (x=0.70), unstrained (x=0.53), and tensile strained (x=0.40) QW SLAs at a fixed carrier density and optical confinement factor, it is found that the noise figure of the tensile strained QW reaches its lowest value of 3.4 dB at average input optical power of -20 dB 相似文献
93.
Hosomi Ryota Otsuka Ren Arai Hirofumi Kanda Seiji Nishiyama Toshimasa Yoshida Munehiro Fukunaga Kenji 《Food science and biotechnology》2016,25(1):107-112
In an effort to clarify whether the lipid-lowering effect of hemoglobin is due to globin protein or heme, this study investigated the effects of dietary porcine hemoglobin (PH) and porcine globin (PG) on lipids contents of serum, liver, and feces in rats. Five-week-old male Wistar rats were divided into 3 dietary groups of 7 rats each, with one group receiving a control diet and the other groups receiving diets containing 1.25% (w/w) PH or 1.18% (w/w) PG for 4 weeks. The PH diet decreased triacylglycerol content in serum and cholesterol in serum and liver, whereas the PG diet reduced triacylglycerol content in serum and cholesterol in liver. Fecal lipid excretion in the PH group was significantly higher than in the PG group. Therefore, PH affected lipid excretion to feces due to globin protein as well as heme. 相似文献
94.
Arai M. Kondo T. Matsutani A. Miyamoto T. Koyama F. 《IEEE journal of selected topics in quantum electronics》2002,8(4):811-816
We carried out the growth of highly strained GaInAs-GaAs quantum wells (QWs) on a patterned substrate for extending emission wavelength on a GaAs substrate. We examined the shift of photoluminescence wavelength of the QWs and showed a large wavelength shift due to the spatial modulation in well thickness and indium composition. We demonstrated a single-mode multiple-wavelength vertical-cavity surface-emitting laser (VCSEL) array on a patterned GaAs substrate covering a new wavelength window of 1.1-1.2 /spl mu/m. By optimizing pattern shape, we achieved multiple-wavelength operation with widely and precisely controlled lasing wavelengths. The maximum lasing span is as large as 77 nm. We carried out a data transmission experiment through 5-km of single-mode fiber with a 2.5 Gb/s/channel. The total throughput reaches 10 Gb/s. The VCSEL-based wavelength-division-multiplexing (WDM) source would be a good candidate for WDM-LAN beyond 10 Gb/s. 相似文献
95.
96.
An investigation on users' requirements for future passive microwave scanning radiometers, especially the advanced microwave scanning radiometer (AMSR), which is one of the Earth Observing System instruments, has been conducted together with a preliminary design of the AMSR system. As a result, mission parameters for the AMSR have been determined while the feasibility of the electronically scanning type of AMSR has been confirmed. In particular, it is found that a beam-switching antenna system that was developed makes possible multifrequency measurement, and multiple beam conical scanning, while preserving polarization purity 相似文献
97.
Photocatalytic activities of CdS crystallites embedded in TiO2 gel as a stable semiconducting matrix 总被引:2,自引:0,他引:2
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
98.
In order to improve device robustness of buried-stripe type 980-nm laser diodes against excess current injection even under high temperature operation, we have introduced a current injection window delineated by a SiNx layer to suppress current injection near the facets. The devices showed complete thermal rollover characteristics at temperatures up to 150°C with 800-mA continuous-wave current injection while devices without the layer failed due to front facet degradation during high temperature tests. We think the improvement of device robustness with a SiNx layer is attributable to suppression of nonradiative recombination of carriers overflowing from the active layers near the facet and to reduced light absorption at the facet brought about by suppression of carrier-induced bandgap shrinkage 相似文献
99.
Carminati Maria Nella; van Gompel Roger P. G.; Scheepers Christoph; Arai Manabu 《Canadian Metallurgical Quarterly》2008,34(5):1098
Two visual-world eye-movement experiments investigated the nature of syntactic priming during comprehension--specifically, whether the priming effects in ditransitive prepositional object (PO) and double object (DO) structures (e.g., "The wizard will send the poison to the prince/the prince the poison?") are due to anticipation of structural properties following the verb (send) in the target sentence or to anticipation of animacy properties of the first postverbal noun. Shortly following the target verb onset, listeners looked at the recipient more (relative to the theme) following DO than PO primes, indicating that the structure of the prime affected listeners' eye gazes on the target scene. Crucially, this priming effect was the same irrespective of whether the postverbal nouns in the prime sentences did ("The monarch will send the painting to the president") or did not ("The monarch will send the envoy to the president") differ in animacy, suggesting that PO/DO priming in comprehension occurs because structural properties, rather than animacy features, are being primed when people process the ditransitive target verb. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Fluorometric determination of nitrite with 4-hydroxycoumarin 总被引:2,自引:0,他引:2