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Partial isothermal sections of the Bi-Fe-Ti system at 700 °C and 900 °C were constructed to investigate the reactivity of Fe with Bi-Ti liquid alloy. In the ternary system, three-phase equilibria such as liquid-Fe-Fe2Ti, liquid-Fe2Ti-Bi2FeTi4, and liquid-Bi9Ti8-Bi2FeTi4 were confirmed at both temperatures. The solubility of Fe in liquid Bi at these temperatures is negligibly small. On the other hand, it is notable that the solubility of Fe in liquid Bi containing Ti at 900 °C is much larger and reaches 2.3 mol pct. Then, we measured the electromotive force (emf) between Bi-20 mol pct Ti alloy and pure Ti at 700 °C in equimolar NaCl-KCl where 1 mol pct TiCl2 was added. From the result, the interaction parameter of the liquid phase in the Bi-Ti system and the standard molar Gibbs energies of formation of Bi9Ti8 and Bi2FeTi4 at 700 °C were estimated. 相似文献
33.
A Method for Reducing the Dead‐Time Voltage and Impedance Voltage in a Series Voltage Compensator
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Atsushi Nakata Masahiro Nozaki Akihiro Torii Akiteru Ueda 《Electrical Engineering in Japan》2014,186(3):85-93
Many research groups are developing series voltage compensators. In a series converter, since a transformer is used in series in the power system, the power system current flows into the voltage source inverter through the transformer. The inverter current, which is determined by the transformation ratio, gives rise to an error voltage that consists of a dead‐time voltage and an impedance voltage. The error voltage is generated even when the reference voltage is zero. This paper describes the mechanism by which the error voltage occurs and proposes a method for reducing the error voltage. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 85–93, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22333 相似文献
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Yuta Fujita Akihiro Ametani Keisuke Nakamura Koichi Yamabuki 《Electrical Engineering in Japan》2014,188(1):36-45
This paper investigates the mutual grounding impedance between vertical grounding electrodes based on field measurements and FDTD simulations. In the case of vertical electrodes, the mutual impedance between the electrodes is almost completely independent of the electrode length, and thus the induced voltage is nearly constant as the electrode length becomes longer. This characteristic is different from that of an overhead conductor, where the electromagnetic‐induced voltage is proportional to the conductor length. The greater the separation distance between the electrodes, the smaller the induced voltage, as in the case of an overhead conductor. The propagation speed increases as the separation increases. It is found that the speed is not necessarily proportional to the inverse of the relative permittivity of the earth. 相似文献
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Satoshi Semboshi Shigeo Sato Mikio Ishikuro Kazuaki Wagatsuma Akihiro Iwase Takayuki Takasugi 《Metallurgical and Materials Transactions A》2014,45(8):3401-3411
We investigated the precipitation processes in Cu-4 mol pct Ti alloy specimens aged at 723 K (450 °C), by means of X-ray diffraction and chemical analyses of the precipitates extracted from the parent alloy specimens. Aging-induced precipitate particles of a spinodally decomposed disorder, α′; those of a metastable order, β′-Cu4Ti; and those of a stable order, β-Cu4Ti, were continuously formed in the aged specimens. The extraction of the precipitate particles from the aged specimens by submergence in a nitric solution allowed for not only the structural analyses of the constituent precipitate phases but also the quantitative evaluation of their chemical compositions and volume fractions. Early during the aging process, the supersaturated Cu solid solution decomposes spinodally in a continuous manner, and an unstable disorder, α′, appears. Then, fine needle-shaped β′-Cu4Ti particles, which have a Ti content of approximately 37.5 mol pct, form in the Cu matrix. During prolonged aging, coarse cellular components composed of the terminal Cu solid solution and stable β-Cu4Ti particles which have a Ti content of 20.5 mol pct nucleate and grow, primarily in the grain boundaries, at the expense of the metastable β′-Cu4Ti particles. The volume fraction of the β′-Cu4Ti particles in the alloy reaches a maximum of approximately 1.7 pct after aging for 24 hours, while that of the β-Cu4Ti particles increases steadily to more than 18 pct after 480 hours. The volume fraction of the fine β′-Cu4Ti particles in the alloy specimens remained constant throughout the age-hardening, indicating that the hardening is primarily owing to the fine dispersion of the β′-Cu4Ti particles and not because of the large volume fraction of coarse β-Cu4Ti particles. 相似文献
38.
Akihiro Shimamura Manabu Fukushima Mikinori Hotta Tatsuki Ohji Naoki Kondo 《Journal of the American Ceramic Society》2016,99(2):440-444
A novel fabrication route to make macroporous silicon carbide (SiC) has been proposed in this study. The route is composed of the following two steps: the fabrication of porous α‐SiC/novolac‐type phenolic composite using hexamethylenetetramine (HMT) as a curing/blowing agent for the novolac monomer and a conventional reaction‐bonded (RB) sintering of the composite. The α‐SiC/novolac‐type phenolic composite was carbonized at 800°C for 2 h in N2 gas and then reacted with the molten silicon at 1450°C for 30 min under vacuum, resulting in the macroporous RB‐SiC with an open porosity of 48% and relatively large pore size of ~110 μm. The compressive strength of the macroporous RB‐SiC was 113 MPa, which is relatively high compared to those reported for macroporous SiC of equivalent porosities and pore sizes. 相似文献
39.
Inside Cover: Biosynthetic Gene Cluster for Surugamide A Encompasses an Unrelated Decapeptide,Surugamide F (ChemBioChem 18/2016)
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