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41.
Yoshihiro Imai Tadashi Tokumasu Hidehiro Nagamura Kiyoshi Miyaike Hisakazu Matsumoto Hiroshi Hasegawa Hiroshi Kusafuka Masatoyo Shibuya Ryukichi Takahashi 《Electrical Engineering in Japan》2007,160(2):30-38
In the combined‐cycle power plant generators are started by using the igniting arrangement up to the ignition rotational speed of the gas turbine. On the other hand, in the case of using the superconducting generator, it is difficult to apply the igniting arrangement used to generate electricity on the combined cycle for the structure as is. We examined the induction motor starting method for the superconducting generator by using the 70‐MW‐class quick‐response excitation superconducting model generator and the VVVF power supply. From the examination, we confirmed the ability to raise the rotational speed from 6 to 360 rpm. Moreover, it was found to be able to start 200‐MW‐class superconducting generators by the induction motor starting method with the analysis. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(2): 30– 38, 2007; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20283 相似文献
42.
Ogura T. Yamada J. Yamada S.-I. Tan-No M.-A. 《Solid-State Circuits, IEEE Journal of》1989,24(4):1014-1020
A 20 kb (512 words×40 b) CMOS associative-memory LSI is described. This LSI performs large-scale parallelism for highly efficient associative operations in artificial intelligence machines. Relational search, large-bit-length data treatment, and quick garbage collection are realized on the single-chip associative-memory LSI. A cell array structure has been designed in order to reduce the chip area. A newly designed simple accelerator circuit allows for high-speed search operations. The LSI is fabricated using 1.2 μm double-aluminium-layer CMOS process technology. 284000 devices have been integrated on a 5.3×7.9 mm2 chip. The measured minimum cycle time and power dissipation at 10 MHz operation are 85 ns and 250 mW, respectively. The associative memory, with its highly efficient associative operation capabilities, promises to be a large step toward the development of high-performance artificial intelligence machines 相似文献
43.
We present a method for combining two bilingual dictionaries to make a third, using one language as a pivot. In this case
we combine a Japanese-English dictionary with a Malay-English dictionary, to produce a Japanese-Malay dictionary. Our method
differs from previous methods in its improved matching through normalization of the pivot language. We have made a prototype
dictionary of around 76,000 Japanese-Malay pairs for 50,000 Japanese head words. 相似文献
44.
Fumikazu Imai Kimio Kunimori Takaaki Manabe Toshiya Kumagai Hisakazu Nozoye 《Thin solid films》1997,310(1-2):184-193
We synthesized titanium oxide thin films on MgO(100) single-crystal substrates by two reactive deposition methods and compared the structures of the thin films formed by these methods. In one method (pulsed-molecular-beam deposition method), molecular oxygen is supplied to the substrates by using a pulsed-molecular-oxygen beam source and deposition of one unit layer of titanium and subsequent supply of molecular oxygen are repeatedly performed. In the other method (radical beam deposition method), atomic oxygen is irradiated to the substrates by using an atomic oxygen beam generated by the radical beam source and irradiation of the atomic oxygen and deposition of titanium are simultaneously performed. In the case of the pulsed-molecular-beam deposition method, the crystal structure was changed by increasing the number of oxygen pulses supplied from the beam source. We found that the crystal structure of titanium oxide depended on the composition ratio of O:Ti in the film. The maximum ratio of O:Ti attainable by this method was 1.85, and at this ratio, (100)-oriented pseudorutile was formed. In the case of the radical beam deposition method, (100)-oriented anatase was formed below the titanium deposition rate of 0.10 nm/s and pseudorutile (TiO2−δ) was formed above 0.15 nm/s. The pseudorutile structure synthesized on this experiment was very stable in air. We concluded that the crystal structure of the pseudorutile is a new crystal structure of titanium oxide. 相似文献
45.
Hideshi Suzuki Masahiro Ogawa Kenji Hironaka Kunio Ito Hisakazu Sunada 《Drug development and industrial pharmacy》2001,27(9):951-958
Nifedipine is a poorly water soluble drug that demonstrates low bioavailability. In a previous study, a coground mixture of nifedipine with sodium deoxycholate (DCNa), a bile salt, immediately produced colloidal particles when dispersed in water. In this study, the effect of the weight fraction of DCNa, grinding time, dissolution media, and storage conditions on colloidal particle formation in solution was investigated. The coground mixture was prepared with a vibration rod mill, and its solid state was characterized using powder X-ray diffraction. A laser diffraction particle size analyzer was used to determine the particle size distribution curve in water. The size of particles formed in solution decreased with an increase in the weight fraction of DCNa and grinding time. A nifedipine-DCNa (1 : 2 w/w) mixture coground for 30 min was used in the experiments. Colloidal particle formation from the coground mixture was also observed in dissolution media of water and a pH 6.8 buffer solution at 37°C. Most precipitates passed through a filter with a pore size of 0.8 μm, but the particle size distribution in water was different from that in the pH 6.8 buffer solution. DCNa exhibited not only micellar solubilization for drug crystals, but also a retarding effect on drug crystal growth in a supersaturated solution. The latter effect could serve to form colloidal particles in solution. When stored under 75% relative humidity at 40°C for 1 month, the amorphous coground mixture crystallized, and the particle size in water markedly increased. Therefore, the weight fraction of DCNa, grinding time, dissolution media, and humidity during storage influence the dissolution characteristics of nifedipine from a coground mixture. 相似文献
46.
Daisuke Kosemura Maki Hattori Tetsuya Yoshida Toshikazu Mizukoshi Atsushi Ogura 《Journal of Electronic Materials》2010,39(6):694-699
Defects and stress gradually accumulate throughout various Si large-scale integration fabrication processes. It is essential
to monitor defects and stress carefully to suppress their unintentional introduction. In this study, we measured the stress
and crystal quality in shallow trench isolation (STI) samples by ultraviolet (UV)-Raman spectroscopy with an extremely high-resolution
wavenumber to evaluate the effect of post-annealing on the recovery of Si crystals. The variations of crystal quality in 200-mm
wafers with STI structures gradually decreased after post-annealing for 4 h, 6 h, and 8 h; however, there was no substantial
difference in the values of full-width at half-maximum of the Raman spectra. Precise measurements of variations of stress
and crystal quality were successfully performed by UV-Raman spectroscopy with a high-resolution wavenumber, which enabled
us to evaluate the STI process accurately. 相似文献
47.
Saku T Fushinobu S Jun SY Ikeda N Nojiri H Yamane H Omori T Wakagi T 《Journal of Bioscience and Bioengineering》2002,93(6):568-574
2-Hydroxy-6-oxo-7-methylocta-2,4-dienoate (6-isopropyl-HODA) hydrolase (CumD), an enzyme of the cumene biodegradation pathway encoded by the cumD gene of Pseudomonas fluorescens IP01, was purified to homogeneity from an overexpressing Escherichia coli strain. SDS-polyacrylamide gel electrophoresis and gel filtration demonstrated that it is a dimeric enzyme with a subunit molecular mass of 32 kDa. The pH optima for activity and stability were 8.0 and 7.0-9.0, respectively. The enzyme exhibited a biphasic Arrhenius plot of catalysis with two characteristic energies of activation with a break point at 20 degrees C. The enzyme has a K(m) of 7.3 microM and a k(cat) of 21 s(-1) for 6-isopropyl-HODA (150 mM phosphate, pH 7.5, 25 degrees C), and its substrate specificity covers larger C6 substituents compared with another monoalkylbenzene hydrolase, TodR Unlike TodF, CumD could slightly hydrolyze 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate (6-phenyl-HODA). A mutant enzyme as to a putative active site residue, S103A, had 10(5)-fold lower activity than that of the wild-type enzyme. 相似文献
48.
ABSTRACT: Antimicrobial activity of salsa mexicana against Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus , and Saccharomyces cerevisiae was studied. The pressed salsa juice suppressed completely the growth of E. coli, B. subtilis , and S. aureus. K. pneumoniae and B. cereus were suppressed partly but Saccharomyces cerevisiae was not suppressed at all by the juice. Three types of microbicidal or microbiostatic components have been found: (1) H+ , (2) volatile compounds, and (3) non-ionized carboxylic acids or analogous compounds. It is proposed that the supplementation of stink bugs in the salsa seen widely in the south of Mexico is used to intensify the herbal odor of the salsa. 相似文献
49.
A method has been developed for the identification of unknown brighteners in detergents by a high-performance liquid chromatography
(HPLC)/mass spectrometry (MS)/ultraviolet (UV)/fluorescence system with MS/MS capability. Ten brighteners from five groups—stilbene,
biphenyl stilbene, pyrazoline, oxazole, and coumarin derivatives—were separated on a C8 reverse-phase HPLC column. The UV and fluorescence detectors positively located the brightener peaks and differentiated betweentrans andcis isomers separated by the chromatographic system. Ion-spray (IS)/MS and IS/MS/MS spectra were then used to identify the structure
of unknown brighteners in detergent products. An HPLC with a diode-array detector provided a quick identification check and
accurate quantitative data for known brighteners, even on overlapping peaks. 相似文献
50.
Semisuperjunction MOSFETs: new design concept for lower on-resistance and softer reverse-recovery body diode 总被引:3,自引:0,他引:3
Saito W. Omura I. Aida S. Koduki S. Izumisawa M. Ogura T. 《Electron Devices, IEEE Transactions on》2003,50(8):1801-1806
A new superjunction (SJ) structure offering remarkable advantages compared with the conventional SJ structure is proposed and demonstrated for a power-switching device. In the proposed structure (semi-SJ structure), an n-doped layer is connected to the bottom of the SJ structure. According to the results of experiment and simulation, the semi-SJ structure has both lower on-resistance and softer recovery of body diode than conventional SJ MOSFETs. The fabricated semi-SJ MOSFETs with breakdown voltage of 690 V realize on-resistance 28% lower than that of the conventional SJ MOSFET with same aspect ratio. The softness factor of the body diode is also improved by a factor of five. The proposed MOSFET is very attractive for H bridge topology applications, such as switching mode power supplies and small inverter systems, thanks to the low on-resistance and the soft recovery body diode. 相似文献