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101.
MASAHIRO TATSUMISAGO AKIRA HAMADA TSUTOMU MINAMI MASAMI TANAKA 《Journal of the American Ceramic Society》1982,65(11):575-577
Glasses were prepared in the wide variety of compositions in the system Li2 O-BaO-Nb2 O5 , which contains no "glass-former," by the twin-roller quenching technique. The crystallization temperature ranges from 500° to 700°C and increases as Li2 O is replaced by BaO. The dielectric constant increases steeply with temperature, reaching an anomalously large value (104 ) in glasses which contain a large amount of Li2 O. Such a temperature dependence of dielectric constant is very similar to that of conductivity in each glass, indicating that the dielectric behavior is caused by polarization due to the ionic motion in glass. The conductivity at 500 K ranges from 10−13 to 10−5 Ω−1 ·cm−1 and the activation energy for conduction from 120 to 40 kJ/mol. The concentration of Li+ ions mainly controls the conductivity and the addition of Ba2+ ions slightly lowers it. 相似文献
102.
103.
We have developed a high energy resolution electron energy-loss spectroscopy (EELS) microscope, which can take spectra from specified small specimen areas and specified small reciprocal space areas to investigate detailed electronic structures. The EELS microscope is equipped with retarding Wien filters as the monochromator and the analyser. The filters are designed to achieve a stigmatic focus. The energy resolutions are 12 meV and 25 meV for cases without and with a specimen, respectively. Spatial and momentum resolutions are 30–110 nm in diameter and 1.1 nm−1 in angular diameter, respectively. EELS spectra are presented to show the performance of this instrument. 相似文献
104.
PANMANAS SIRISOMBOON MUNEHIRO TANAKA SHUJI FUJITA TAKAYUKI KOJIMA 《Journal of texture studies》2000,31(6):679-690
The relationship between texture and pectin constituents and some related compounds of the Japanese pear (Pyrus serotina Render var. culta 'Housui') during fruit enlargement and ripening was studied. The modulus of elasticity, deformation ratio, and relaxation value from the flat plate compression test, and all the properties from the puncture test were affected by the pectin constituents, alcohol insoluble solids, and soluble solids. The hardness and deformation of the fruit obtained from the plate compression test might depend on the combination of the alcohol insoluble solids in fresh weight and weight of the fruit. The oxalate soluble pectin both in alcohol insoluble solids and in fresh weight affected the fruit texture more than the water soluble pectin. The solubitization of nonsoluble pectin to water soluble pectin appeared to influence the textural properties more than that of the nonsoluble pectin to oxalate soluble pectin. The puncture test was superior in analyzing the textural properties of the Japanese pear fruits with regard to changes in the pectin constituents. 相似文献
105.
TAKESHI TAGUCHI JENG-REN LO MUNEHIKO TANAKA YUJI NAGASHIMA KEISHI AMANO 《Journal of food science》1989,54(6):1521-1523
Changes in activities of actomyosin, acto-heavy meromyosin (acto-HMM), and acto-subfragment-I (acto-S-I) ATPases from tuna and sardine due to heat treatment (20°, 25°, 30°, 35°, 40°C) were compared for ordinary muscle and dark muscle. Activation of ordinary muscle actomyosin Mg-ATPases was more than doubled for tuna and tripled for sardine by heating at 35°C, while activation of dark muscle actomyosin was not observed at any temperature. The occurrence of thermal activation corresponded to a rapid loss of the EDTA-ATPase activity. Activation of hybrid actomyosins from dark and ordinary muscles was dependent upon myosin. For acto-HMM and acto-S-I thermal activation was not observed. The role of myosin tail fragments in thermal activation is discussed. 相似文献
106.
107.
LOW- AND HIGH-CYCLE FATIGUE PROPERTIES OF VARIOUS STEELS SPECIFIED IN JIS FOR MACHINE STRUCTURAL USE
K. TANAKA S. NISHIJIMA S. MATSUOKA T. ABE F. KOUZU 《Fatigue & Fracture of Engineering Materials & Structures》1981,4(1):97-108
Abstract —Low-cycle fatigue properties were investigated on four carbon steels and five low alloy steels specified in JIS (Japanese Industrial Standard) for machine structural use, which are the most commonly used in Japan. Several different heats from each of several representative manufacturers were sampled so as to represent the average fatigue characteristics of current materials. The cyclic deformation behaviour of material was denned by comparing the monotonie yield stress on the extrapolated tensile work hardening curve with the cyclic yield stress in the cyclic stress-strain curve determined by incremental step test. The normalized ferrite-pearlitic steels cyclically hardened, while the quench-tempered martensitic were cyclically stable or softened. The S–N relations derived from the strain-controlled low-cycle tests were compared with the results obtained by load-controlled high-cycle tests. The extrapolated S–N curves based on the cyclic stress-strain curve predicted the fatigue strength in the high-cycle range to be stronger for cyclic-hardening steels, but weaker for cyclic-softening steels. The predicted S–N curves for stable steels coincided with the high cycle test data. The fatigue limit had a proportional relationship with cyclic yield stress, slightly depending on the cyclic deformation behaviour. On the other hand, the cyclic yield stress was found to exhibit a very good linear correlation with the monotonie tensile strength, independent of cyclic deformation behaviour. This explains the empirical law that the fatigue limit is approximately proportional to the tensile strength. 相似文献
108.
Scaling Law of Coupling Coefficient and Coil Size in Wireless Power Transfer Design via Magnetic Coupling
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CHIAKI NAGAI KENJI INUKAI MASATO KOBAYASHI TATSUYA TANAKA KENSHO ABUMI TAKEHIRO IMURA YOICHI HORI 《Electrical Engineering in Japan》2018,202(4):21-30
Wireless Power Transfer (WPT), such as magnetic resonant coupling using a magnetic field, is being studied and discussed for a wide variety of applications. When the transmission distances are large, very large transmitters and receivers need to be considered. However, in the early stages of an investigation, it might be prohibitive to manufacture and evaluate coils of such a large size. To reduce costs and effort, a scaling law can be used to estimate the WPT efficiency of very large coils using the results of smaller coils. In this paper, a scaling law is proposed that relates the coil size to the coupling coefficient, assuming the ratio between the coil diameter and coil length remains constant. The coupling coefficient is one of the parameters that determine the maximum efficiency of magnetic field WPT. The proposed method was verified by an electromagnetic field simulator and experiment. The results of this study provide an easy method for estimating the WPT efficiency of very large coils. 相似文献
109.
Two optimal control problems which have the same optimal feedback control laws and identical minimum costs are said to be equivalent. The conditions for the equivalence of two optimal control problems have been presented by other authors, but it seems that the equivalence conditions given by other authors are not complete. In this paper, a necessary and sufficient condition for the equivalence classes is derived. 相似文献
110.
KEN‐ICHIRO TANAKA MASARU HASEGAWA ATSUSHI MATSUMOTO 《Electrical Engineering in Japan》2017,199(4):55-64
This paper proposes a novel flux estimation method for the position sensorless control of permanent magnet synchronous motors (PMSMs). In general, the stator flux linkage for position estimation in PMSMs is obtained using the pure integration of voltages. The infinite dc gain of the pure‐integrator, however, causes numerical drifts in the obtained stator flux linkage due to the dc offset in the input of this integrator. To address this problem, a quasi‐integrator is often substituted instead of the pure integrator to restrict the dc gain, leading to another problem in which the phase characteristics vary according to the operating frequency. As a result, the ideal phase characteristics (?90° constant) cannot be held, and the position estimation performance deteriorates. Therefore, this paper proposes a phase characteristic correction method for quasi‐integrators using all‐pass filters, which achieves extremely precise estimation under transient conditions as well as in steady state. 相似文献