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51.
52.
Koji Ishida Ken Hirota Osamu Yamaguchi Hideki Kume Suguru Inamura Hiroki Miyamoto 《Journal of the American Ceramic Society》1994,77(5):1391-1395
In the system ZrO2 –Al2 O3 , a new method for preparing ZrO2 solid solutions from ZrCl4 and AlCl3 using hydrazine monohydrate is investigated. c -ZrO2 solid solutions containing up to ∼40 mol% Al2 O3 crystallize at low temperatures from amorphous materials. The formation mechanism is discussed from IR spectral data. The values of the lattice parameter α increase linearly from 0.5072 to 0.5105 nm with increasing Al2 O3 content. At higher temperatures, transformation of the solid solutions proceeds as follows: c ( SS ) → t ( ss ) → t ( ss ) +α-Al2 O3 → m +α-Al2 O3 . m -ZrO2 –α-Al2 O3 composite ceramics are fabricated by hot isostatic pressing for 2 h at 1250°C and 196 MPa. Microstructures and mechanical properties are examined, in connection with increasing Al2 O3 content. 相似文献
53.
Toshio Ogasawara Yuichi Ishida Takashi Ishikawa Takahira Aoki Toshiyuki Ogura 《Composites Part A》2006,37(12):2236-2240
Helium gas permeability of silicate clay (montmorillonite) particles/epoxy nanocomposites was examined. The incorporation of increasing amounts of montmorillonite particles reduced the helium gas permeability. Based on Fick’s law, gas permeation behavior of the nanocomposite was evaluated. With the increase of montmorillonite loading, gas diffusivity decreased, while gas solubility increased. Helium diffusion behavior is in agreement to the numerical results based on the Hatta–Taya–Eshelby theory. It has been revealed that dispersion of nanoscale platelets in polymer is effective in improving gas barrier property. 相似文献
54.
Tunable Optical Notch Filter Realized by Shifting the Photonic Bandgap in a Silicon Photonic Crystal Line-Defect Waveguide 总被引:1,自引:0,他引:1
Chu T. Yamada H. Gomyo A. Ushida J. Ishida S. Arakawa Y. 《Photonics Technology Letters, IEEE》2006,18(24):2614-2616
A tunable optical notch filter was realized by thermally shifting the TM-like (the light's electric field perpendicular to the substrate) bandgap of a silicon photonic crystal slab W1 line-defect waveguide with silica cladding. This device is compact-its footprint is 340times16 mum2, excluding the electrode pads. The 3-dB bandwidth of the device was about 5 nm, and the extinction ratio at the center wavelength was as high as 40 dB. A maximum center wavelength shift of 17.9 nm was attained at a heating power of 0.7W, with a tuning efficiency of 25.5 nm/W. The tuning response time was less than 100 mus 相似文献
55.
Experimental investigation and thermodynamic calculation of the phase equilibria in the Cu-Sn and Cu-Sn-Mn systems 总被引:2,自引:0,他引:2
X. J. Liu R. Kainuma C. P. Wang I. Ohnuma K. Ishida 《Metallurgical and Materials Transactions A》2004,35(6):1641-1654
The phase equilibria in the Cu-rich portion of the Cu-Sn binary and Cu-Sn-Mn ternary systems have been determined using the
diffusion-couple method, differential scanning calorimetry (DSC), high-temperature electron diffraction (HTED), and high-temperature
X-ray diffraction (HTXRD) techniques. The present experimental results on the binary Cu-Sn system show the presence of the
two-stage, second-order reaction A2 → B2 → D03 in the bcc-phase region, rather than a two-phase equilibrium between the disordered bcc (A2) and the ordered bcc (D03) phases, as reported before. Phase equilibria in the Cu-Sn-Mn ternary system in the composition range of 0 to 30 at. pct
Sn and 0 to 30 at. pct Mn at 550 °C, 600 °C, 650 °C, and 700 °C have been determined, and a ternary compound (Cu4MnSn) with a very small solubility has been detected. A thermodynamic analysis of the Cu-Sn-Mn ternary system including the
Cu-Sn and Mn-Sn binary systems has also been carried out by the CALPHAD (Calculation of Phase Diagrams) method, in which the
Gibbs energy of the bcc phase is described by the two-sublattice model in order to take into account the second-order A2/B2
ordering reaction. A consistent set of optimized thermodynamic parameters for the Cu-Sn-Mn system for describing the Gibbs
energy of each phase results in a better fit between calculation and experiment. 相似文献
56.
57.
Masahiro Ishida Toru Nakura Takashi Kusaka Satoshi Komatsu Kunihiro Asada 《Journal of Electronic Testing》2016,32(3):257-271
This paper proposes a power integrity control technique for dynamically controlling power supply voltage fluctuations for a device under test (DUT), and demonstrates its effectiveness for eliminating the overkills/underkills due to the difference of power supply impedance between an automatic test equipment (ATE) and a practical operating environment of the DUT. The proposed method injects compensation currents into the power supply nodes on the ATE system in a feed-forward manner such that the ATE power supply waveform matches with the one on the customer’s operating environment of the DUT. A method for calculating the compensation current is also described. Experimental results show that the proposed method can emulate the power supply voltage waveform under a customer’s operating condition and eliminate 95 % of overkills/underkills in the maximum operating frequency testing with 105 real silicon devices. Limitations and applications of the proposed method are also discussed. 相似文献
58.
59.
This paper presents the silicon based on-chip antenna using a LC resonator. The proposed antenna consists of a stacked capacitor and a spiral inductor on silicon substrate. The spiral inductor structure without underpass was proposed for improvement the performance of the silicon based-antenna. The resonant frequency of the fabricated antenna was measured as 465 MHz. Its return loss was 23.4 dB at resonant frequency. The antenna has a gain of ?35.75 dBi due to small size and silicon substrate. However, the fabricated antenna has good performance in the near-field. 相似文献
60.
Development of Motor Model of Rotor Slot Harmonics for Speed Sensorless Control of Induction Motor 下载免费PDF全文
This paper proposes a novel mathematical dynamic model to represent the steady‐state and transient‐state characteristics of rotor slot harmonics of an induction motor for sensorless control. Although it is well known that the rotor slot harmonics originate from the mechanical structure of the induction motor, a mathematical model that describes the relationship between the stator/rotor currents of the induction motor and the slot harmonics has not yet been proposed. Therefore, in this paper, a three‐phase model of the induction motor that depicts the rotor slot harmonics is developed by taking into consideration the magnetomotive force harmonics and the change in the magnetic air gap caused by the rotor slots. The validity of the proposed model is verified by comparing the experimental results and the calculated values. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 63–74, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22478 相似文献