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61.
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Slags used in steelmaking and continuous casting that contain SiO2, Na2O, and CaF2 tend to be unstable and gaseous. Species, such as NaF and SiF4, evolve simultaneously from these slags at steelmaking temperatures. In addition, the reaction between NaF and SiF4 can occur to produce Na2SiF6 (sodium hexafluorosilicate). In a previous study on the vaporization of NaF into an inert gas stream, the diffusivity of
NaF in argon, nitrogen, and helium was measured. In this study, the rate of NaF vaporization in a SiF4 atmosphere was measured. Ternary diffusion coefficients were then evaluated from the binary diffusion coefficients obtained
in a previous study, and a kinetic analysis was carried out. The rate calculations were found to be in accord with the measured
results, indicating that the experiments were carried out in a regime where diffusion of NaF from the surface of the sample
was rate controlling. 相似文献
63.
Yoshiaki Mizuno Takami Tohyama Sadamichi Maekawa 《Journal of Low Temperature Physics》1999,117(3-4):389-393
We examine two-spin (2S) and cyclic four-spin (4S) magnetic interactions in insulating ladder and two-dimensional (2D) cuprates. By a comparison of eigenstates between d-p and Heisenberg models, we evaluate magnitudes of these interactions. We find that the 4S interaction is 10 % of nearest neighboring 2S interaction, and a diagonal 2S interaction is considerably small. The 4S interaction for a ladder cuprate is larger than that for 2D one, and plays an important role in the low-energy excitation. The Heisenberg ladder with the obtained 2S and 4S interactions reproduces very well the experimental result of the temperature dependence of the magnetic susceptibility. 相似文献
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Bismuth titanate (BiT) based composites containing silver particles are fabricated by a solution chemical process. Incorporation
of silver particles does not result in unwanted reaction phase. SEM micrographs reveal fine silver particles distribute at
BiT grain boundaries and into larger BiT plate-like grains. With the addition of silver, the dielectric constant increases
up to ∼10 times higher than that of pure BiT ceramic, which can be attributed to the effective electric fields developed around
the dispersed metal particles and the percolation effect. Additionally, the dielectric losses are significantly reduced by
incorporating silver particles, and the values of BiT/Ag composites are lower than 0.5%. The dielectric properties of BiT/Ag
composites are nearly frequency independent in the measured frequency range (1 kHz to 1 MHz). 相似文献
69.
Yoshiaki Kano Kyohei Watanabe Takashi Kosaka Nobuyuki Matsui 《Electrical Engineering in Japan》2011,174(1):49-58
This paper proposes a new modeling approach for circuit‐field‐coupled time‐stepping electromagnetic analysis of a saturated interior permanent magnet synchronous motor (IPMSM). To predict the drive performance quickly, the proposed approach consists of a dynamic simulator based on a new analytical model of the d‐ and q‐axis magnetization characteristics (λ‐id‐iq‐θ). The model can take into account not only cross‐saturation but also the harmonics of the inductance distributions and EMF waveforms. The validity of the model is verified from suitable simulation results for the instantaneous current and torque waveforms of the IPMSM. The proposed analysis leads to a dramatic reduction in the computation time compared to circuit‐field‐coupled time‐stepping FEA, while maintaining analytical accuracy. The effectiveness of the proposed method is experimentally verified using a 10‐kW, 15,000‐rpm concentrated‐winding IPM motor. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(1): 49–58, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21024 相似文献
70.
Hirofumi Chiba Yukio Suzuki Yoshiaki Yasuda Mitsuyasu Kumagai Takaaki Koyama Shuji Tanaka 《Electrical Engineering in Japan》2021,214(1):62-68
This paper reports a deep‐ultraviolet LED (deep‐UV‐LED) package based on silicon MEMS process technology (Si‐PKG). The package consists of a cavity formed by silicon crystalline anisotropic etching, through‐silicon vias (TSVs) filled with electroplated Cu, bonding metals made of electroplated Ni/AuSn and a quartz lid for hermetic sealing. A deep‐UV LED die is directly mounted in the Si‐PKG by AuSn eutectic bonding without a submount. It has advantages in terms of size, heat dissipation, light utilization efficiency, productivity and cost over conventional AlN ceramic packages. We confirmed a light output of 30 mW and effective reflection on Si (111) cavity slopes in the Si‐PKG. Based on simulation, further improvement of the optical output is expected by optimizing DUV‐LED die mount condition. 相似文献