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101.
The oxidation behavior of an Fe61B15Zr8Mo7Co5Y2Cr2 bulk metallic glass (Fe7-BMG) was investigated in three oxygen-containing atmospheres over the oxygen partial pressure range of 103–105 Pa at 650 °C. The oxidation kinetics of the Fe7-BMG followed the parabolic rate law in all cases, indicating that solid-state diffusion is the rate-controlling step during oxidation. The oxidation rate constants (kp values) increased with increasing oxygen partial pressure, implying a typical scaling behavior with a p-type semiconductivity. Duplex scales formed on the Fe7-BMG consisted of an outer layer of mostly iron oxides (Fe2O3/Fe3O4) and minor amounts of B2O3, and a heterophasic inner layer of mostly tetragonal-ZrO2 (t-ZrO2) intermixed with non-oxidized intermetallic phases. 相似文献
102.
This paper describes a TV signal compression scheme which may become a common practice for analog video transmission and broadcast via satellite by the year 2000. The technique uses twodimensional interfield processing to reduce the video bandwidth with minimum degradation in subjective quality, and time multiplexed with analog multiplexing technique for transmission in component format. Computer simulations of the processing technique on the test slides, and analysis of subjective quality andS/N expected over a typical satellite link, are reported. A proof-of-concept prototype being developed at COMSAT Laboratories is also outlined. 相似文献
103.
104.
A production/inventory system consisting of work stations in series and a finished product warehouse is introduced. Bounds for the throughput are developed through the analysis of the reversed system of tandem queues. Examples are provided to show the bounds. 相似文献
105.
In reactions between solders and Cu, additions of minor alloying elements, such as Fe, Co or Ni, to solders often reduce the
Cu3Sn growth rate. Nevertheless, the mechanism for this effect remains unresolved. To provide more experimental observations
that are essential for uncovering this mechanism, growth of Cu3Sn in the reaction between Cu and high-lead solders with or without Ni additions has been studied. The solders used for this
study were 10Sn-90Pb and 5Sn-95Pb doped with 0 wt.%, 0.03 wt.%, 0.06 wt.%, 0.1 wt.% or 0.2 wt.% Ni. Reaction conditions included
one reflow at 350°C for 2 min and solid-state aging at 160°C for up to 2000 h. The effect of Ni on the growth of Cu3Sn is discussed in detail based on the experimental results. 相似文献
106.
Some sufficient conditions for the global exponential stability of cellular neural networks with variable coefficients and
time-varying delays are obtained by a method based on a delayed differential inequality. The method, which does not make use
of Lyapunov functionals, is simple and effective for the stability analysis of cellular neural networks with variable coefficients
and time-varying delays. Some previous results in the literature are shown to be special cases of our results.
相似文献
107.
108.
Chia-Hsiung Kao Ping-Yu Tsai Wen-Pin Lin Yao-Jen Chuang 《Analog Integrated Circuits and Signal Processing》2008,55(3):205-212
A high efficiency and low distortion and switching power amplifier is proposed. We use feedback to reduce the total harmonic
distortion (THD) and the DC output bias current. The experimental results show that the proposed circuit has 0.24% total harmonic
distortion and 91% power efficiency while the DC output bias current is 12 μA at 1.5 V supply voltage. 相似文献
109.
110.
Ming-Kwei Lee Chi-Hsing Chu Yu-Chu Tseng Jong-Min Shyr Chia-Hsiung Kao 《Electron Device Letters, IEEE》2000,21(12):587-589
A porous silicon Al Schottky barrier diode shows differential negative resistance. The thin wires in porous silicon have much lower electron mobility than that of thick wires, due to electron surface scattering from space confinement. The energy of carriers in thick wires increases with applied bias. Some carriers can overcome the conduction-band discontinuity and flow into the thin wires. The negative differential resistance comes from the mobility difference between thick wires and thin wires in porous silicon. 相似文献