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1.
MASARU MIYAYAMA SHINICHI KATSUTA YOSHIHIRO SUENAGA HIROAKI YANAGIDA 《Journal of the American Ceramic Society》1983,66(8):585-588
Electrical conduction in tetragonal β-Bi2 O3 doped with Sb2 O3 was investigated by measuring electrical conductivity, ionic transference number, and Seebeck coefficient. The β-Bi2 O3 doped with 1 to 10 mol% Sb2 O3 was stable up to 600°C and showed an oxygen ionic and electronic mixed conduction, where the electron conduction was predominant at low oxygen pressures. The oxygen-ion conductivity showed a maximum at 4 mol% Sb2 O3 , whereas the activation energy for the ionic conduction remained unchanged for 4 to 10 mol% Sb2 O3 -doped specimens. These results were interpreted in terms of the oxygen vacancy concentration and the distortion of the tetragonal structure. The electron conductivity and its oxygen pressure dependence decreased with increasing Sb2 O3 content. The fact that Sb5+ is partially reduced by excess electrons in heavily doped β specimens at low oxygen pressures is explained. 相似文献
2.
Gas Sensing Characteristics of Porous ZnO and Pt/ZnO Ceramics 总被引:2,自引:0,他引:2
SHINICHIRO SAITO MASARU MIYAYAMA KUNIHITO KOUMOTO HIROAKI YANAGIDA 《Journal of the American Ceramic Society》1985,68(1):40-43
Changes in resistivity and chemical changes in reducing gases were measured for porous zinc oxide ceramics with and without a platinum catalyst at 300° and 400°C to examine the gas sensing mechanism and the effect of platinum additions. Reducing gases were oxidized to CO2 and Hz2 on the sensor surfaces. Platinum addition promoted the oxidation of reducing gases but did not lead to an increase in the resistivity change at 400°C. The reaction sequences for the gas sensing process are proposed, taking into account partially oxidized intermediates of hydrocarbons and oxidation on platinum without an electron transfer process. 相似文献
3.
The dependence of grain-boundary resistivity and resistance per square centimeter of grain-boundary surface on grain-boundary density (D) in yttria-stabilized zirconia was investigated using reported data. The grain-boundary resistivity increased with increasing D in the high-D region but was independent of D in the low-D region. These results were interpreted in terms of intrinsic effects such as lattice irregularity and extrinsic effects such as impurity segregation. 相似文献
4.
A two-level method to find the optimal control of a linear system is presented. We consider that the system is composed of coupled subsystems. And we solve two decoupled first-level problems and one coordinating second-level problem iteratively. When the system can be decoupled into weakly coupled subsystems, the solution fast converges to the optimal. 相似文献
5.
MASARU ISHIDA YUTAKA FUKUI KEISUKE EBISUTANI 《International Journal of Electronics》2013,100(1):151-158
A novel active-R synthesis baaed on the single-pole rolloff characteristics of operational amplifiers is described. Various types of driving-point impedance, such as an inductance, frequency-dependent negative-resistance and frequency-dependent negative-inductance are systematically derived by the suitable choice of the amplifier transfer function. It is shown by experiments that the inductance simulator presents reliable high frequency performance. 相似文献
6.
The visible spectra of a series of 1,4-disubstituted benzoanthraquinone dyes in benzene solution has been measured. The position of the absorption maxima of the dyes has been found to be well correlated with a mean ionization potential of the substituent groups. An annelation of anthraquinone dyes in the position of 2, 3 or 6, 7produced a small hypsochromic shift, while 5,6-annelation produced a large bathochromic shift. The additive properties on the absorption maximum of dibenzoanthraquinone dyes were also observed. 相似文献
7.
JOYCE MOLINELLI MINORU TOMOZAWA MASASUKE TAKATA 《Journal of the American Ceramic Society》1985,68(3):165-168
The variation with water content of dc conductivity and Na diffusion coefficient for the Na2 O · 4siO2 and Na2 O · 2SiO2 glass systems was found to be similar to that of the Na2 O.3SiO2 series reported earlier. The conductivity was estimated for the ternary system Na2 O-H2 O-SiO2 by combining the present results with the previous data on the Na2 O · 3SiO2 system. When the conductivity of those glasses with a constant [Na2 O] + [H2 O] content was plotted against water content, a pronounced mixed "alkali" effect was demonstrated. The Haven ratio, calculated by comparison of the dc conductivity to the Na diffusion coefficient at 100°C for each of the three glass systems, was found to increase toward unity with increasing water content. This suggests that the addition of water reduces the number of sodium charge carriers. The subsequent increase in conductivity beyond the minimum with the introduction of larger amounts of water is, probably, due to an increase in the mobility of the Na+ ions. 相似文献
8.
Na2 O·3 SiO2 glasses of high water content were prepared under high-pressure, hydrothermal conditions. The sodium diffusion coefficient, DNa , in these glasses measured at 100°C depended strongly on H2 O content. With increasing H2 O content, DNa . at 100°C decreased initially to a minimum at 3∼4 wt% H,O and then increased. This behavior of DNa . Was similar to that of dc conductivity. 相似文献
9.
KENICHI AOKI MASAKAZU KANEZASHI MASARU ITOH HARUKI MATSUURA 《International journal of systems science》2013,44(11):1977-1989
A new method for solving a power generation scheduling problem in an electric power system is presented. The objective is to determine the hourly start-up/ shut-down schedules of all generators so that forecasted hourly power demands per day may be met and total operating costs, the sum of setup and fuel costs for a given day, may be minimized. The problem may be formulated as a large-scale combinatorial optimization problem which includes 0-1 variables representing the start-up/shut-down of generators and continuous variables representing the power outputs. Determination of an optimalsolution within practical time limits is consequently difficult. Until now, the lagrangian relaxation method has been studied as it appeared to be the most practical method for obtaining an approximate solution to the problem. The efficiency of this method, however, depends on how the Lagrange multipliers are determined. Here, it is proposed that the Lagrange multipliers be estimated by utilizing the neural network and results determined from examination of the possibility of applying the backpropagation algorithm to pattern recognitions which presume the relationship between power demand pattern and Lagrange multipliers are reported. Through numerical experiments, it was established that the Lagrange multipliers, estimated by the neural network, are applicable to the problem. 相似文献
10.
KAZUO TORAICHI MASARU KAMADA SHUICHI ITAHSHI RYOICHI MORI 《International journal of systems science》2013,44(12):2491-2505
The rectangular, triangular, and Parzen windows, which have been defined independently of each other, are obtained by repeating convolution integrals of the rectangular window with itself. They are extended to make a series of window functions. This series has the advantage that the sidelobe fall-off is variable though it has the disadvantage that the mainlobe band-width for the same highest sidelobe level is 1–1·3 times those of the gaussian, Kaiser, Dolph–Chebyshev or Blackman–Harris windows. Moreover, this series has a desirable mainlobe bandwidth of 0·85–1 times that of cosx x windows for the same highest sidelobe level and sidelobe fall-off. Thus, this series is useful in designing window functions whose mainlobe bandwidth is in between that of the gaussian or Kaiser windows and that of cosx x windows and whose sidelobe fall-off is as good as that of the cosx x windows. 相似文献