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排序方式: 共有817条查询结果,搜索用时 31 毫秒
761.
We show here how a Ru(bpy)2(CE-bpy) complex can be used for the ECL detection of sodium ion in both aqueous and nonaqueous media. Recognition of Na+ by the crown ether moiety in CE-bpy results in a significant increase in the ECL emission intensity of the complex. 相似文献
762.
J.?AzaiezEmail author K.?Chiba F.?Chinesta A.?Poitou 《Archives of Computational Methods in Engineering》2002,9(2):141-198
Summary Short fiber reinforced composites have gained increasing technological importance due to their versatility that lends them
to a wide range of applications. These composites are useful because they include a reinforcing phase in which high tensile
strengths can be reached, and a matrix that allows to hold the reinforcement and to transfer applied stress to it. It is a
well-known fact, that such materials can have excellent mechanical, thermal and electrical properties that make them widely
used in industry. During the manufacture process, fibers adopt a preferential orientation that can vary significantly across
the geometry. Once the suspension is cooled or cured to make a solid composite, the fiber orientation becomes a key feature
of the final product since it affects the elastic modulus, the thermal and electrical conductivities, and the strength of
the composite material. In this work we analyzed the state-of-the-art and the recent developments in the numerical modeling
of short fiber suspensions involved in industrial flows. 相似文献
763.
Masahide Ooshima Satoru Miyazawa Tazumi Deido Akira Chiba Fukuzo Nakamura Tadashi Fukao 《Electrical Engineering in Japan》1996,117(4):95-108
Super-high-speed and high-power electric machines are required for turbomolecular pumps and spindle drives. High rotational speed and high-power drives can be achieved with bearingless motors. In this paper, a bearingless motor with principles of permanent magnet-type synchronous motors is proposed. High-power factor and high efficiency can be expected in permanent magnet-type bearingless motors. The proposed bearingless motor is a 4-pole permanent magnet synchronous motor, in which additional 2-pole windings are wound together with 4-pole motor windings in stator slots. With currents of 2-pole windings, radial magnetic forces are produced to support a rotor shaft. Principles of radial force production of surface-mounted permanent magnet bearingless motors are analyzed mathematically. The relationships between radial forces and the permanent magnet thickness were derived. From these relationships, the optimal permanent magnet thickness to produce radial forces efficiently is found. A test machine was built to confirm the relationships of radial forces, currents and voltages. 相似文献
764.
Mitsuyasu Kido Tomio Chiba Hiroyuki Kudo Junzou Kawakami Tadao Kawai 《Electrical Engineering in Japan》1992,112(5):88-99
Power system control and protection equipment has required higher sensitivity and operational reliability than conventional one. Studies of digital signal processing suitable for electric power systems fulfill this objective using fast sampling and digital filtering by a 32-bit floating point DSP (Digital Signal Processor). The sampling rate of 3 kHz is carefully selected in order to separate the power spectrums of the A-D conversion output errors from the signal bandwidth. The new 12-bit A-D conversion unit equipped with a recursive-type digital filter achieved the equivalent high resolution of 14-bit conversion. This paper describes the design concept and the characteristics showing applications to current differential relays, distance relays and power system controllers. 相似文献
765.
766.
This study shows the effects of a selective endothelin ET(B) receptor agonist, IRL 1720 {Ac-[Ala11,15]endothelin-1-(8-21)}, on cardiovascular responses in anesthetized spontaneously hypertensive rats and Wistar-Kyoto rats. Single intravenous bolus injection of IRL 1720 caused a dose-related short-lasting fall in blood pressure, left ventricular pressure and myocardial contractility. However, repeated intravenous bolus injection of 10(-5) mol/kg IRL 1720 produced a biphasic response consisting of an initial short-lasting decrease followed by a sustained increase in these parameters. The initial decrease was reduced, whereas the following increase was enhanced with the repeated injections of IRL 1720. The cardiovascular pressor response was not inhibited by the endothelin ET(A) receptor antagonist, FR139317 ((R)2-[(R)-2-[(S)-2-[[1-(hexahydro-1H-azepinyl)]carbonyl] amino-4-+methylpentanoyl] amino-3-[3-(1-methyl-1H-indolyl)]propionyl]amino -3- (2-pyridyl)propionic acid). The effects of IRL 1720 were qualitatively similar but more potent in spontaneously hypertensive rats than in Wistar-Kyoto rats. These results suggest the existence of two types of endothelin ET(B) receptor for IRL 1720: a tachyphylactic endothelin ET(B) receptor that mediates cardiovascular depressor responses and a less tachyphylactic endothelin ET(B) receptor that mediates pressor responses in the rat. 相似文献
767.
768.
Tohru Ohyama Kazuo Jin Yoshinobu Katoh Yoshiaki Chiba Katsuhiro Inoue 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(3):F8
Chemical reactions in foods II 相似文献
769.
We present the development of a procedural method for texturing and modeling different kinds of woven canvas used to support easel paintings. The detailed macro- and microgeometry of textiles and different weaving patterns found in woven fabrics is conveniently simulated by procedural displacement and surface shading. The common varieties of canvas used in art production since the Italian Renaissance period are presented and recreated. The anatomy of an oil-based painting is briefly introduced and a visual simulation of decay presented. We also apply our texturing and shading techniques to a simple geometric representation of painting to help visualize the changing characteristics developed during the aging process of a canvas support kept in uncontrolled environmental conditions. 相似文献
770.