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121.
The unity gain buffer will be good to design high frequency SCF if its resistiveeffects can be eliminated,and therefore the whole parasitic sensitivities will greatly be reduced.On the basis of this concept,a novel parasitic tolerant SC DTE(differential transconductanceelement)is proposed.SC floating inductor and integrator fit for high frequency applications areformed by the DTE.The computer simulation and experiment on a third order elliptic LP filterverify its validity. 相似文献
122.
对苯二甲酸精制过程中几个反应工程问题探讨 总被引:5,自引:0,他引:5
从反应工程角度出发,对TA(对苯二甲酸)加氢宏观反应过程进行了分析,认为三相床层中存在的粘滞液膜和滞留液囊对外湿润率有较大影响,在对影响TA精制过程的几个反应工程问题进行计算和讨论的基础上,探讨了PTA(精对苯二甲酸)装置长周期,高负荷稳定运行的工艺条件。 相似文献
123.
JaeHyunKim JounHoLee JiChulLim ChangHoonLee MooHyoungSong JuYeonYoon HeeDongChoi JeomJaeKim ChangHoOh SangDeogYeo 李路海 《现代显示》2004,31(5):31-33
薄膜晶体管液晶电视(TFT-LCD TV)因为具有薄、轻、紧凑和可随意放置的特点,已经占据了大部分电视机市场。除了这些物理特性以外,最重要的特性是已具有了良好像质的对比度。为了将对比度提高到1:600以上,对偏振片膜、背光源板、滤色片树脂、电极锥角和摩擦条件等都进行了研究。优化的背光板组合,光滑的电极锥角和摩擦方法的控制是提高对比度的主要控制因素。应用新开发的滤色片树脂,对获得高对比度最为有效。 相似文献
124.
Personality is an essential feature for creating socially interactive robots. Studies on this dimension will facilitate enhanced human–robot interaction (HRI). Using AIBO, a social robotic pet developed by Sony, we examined the issue of personality in HRI. In this gender-balanced 2 (AIBO personality: introvert vs. extrovert) by 2 (participant personality: introvert vs. extrovert) between-subject experiment (N = 48), we found that participants could accurately recognize a robot's personality based on its verbal and nonverbal behaviors. In addition, various complementarity attraction effects were found in HRI. Participants enjoyed interacting with a robot more when the robot's personality was complementary to their own personalities than when the robot's personality was similar to their own personalities. The same complementarity attraction effect was found in participants' evaluation of the robot's intelligence and social attraction. Participants' feelings of social presence during the interaction were a significant mediator for the complementarity attraction effects observed. Practical and theoretical implications of the current study for the design of social robots and the study of HRI were discussed. 相似文献
125.
126.
The stability of five major phenolics, namely (−)-epicatechin (EC), procyanidin B2 (PC-B2), chlorogenic acid (ChA), hyperoside (HP) and isoquercitrin (IQ), in hawthorn fruits and a canned hawthorn drink were evaluated during 6 months of storage in the dark at three different temperatures (4, 23 and 40 °C). HPLC with a diode-array detector was used to determine the contents of the individual compounds. The results showed that the studied phenolics in the hawthorn fruits and the drink were both stable at 4 °C and relatively unstable at 23 and 40 °C with varied extents of degradation. At room temperature (23 °C), marked degradations of EC and PC-B2 were observed in both the fruits and the drink with around 50% and 30% decrease after a 6-month storage, respectively. A more significant decrease of the phenolics was observed at 40 °C, especially for EC and PC-B2, which were almost completely degraded after a 6-month storage. HP, IQ and ChA were relatively stable at 23 °C, but unstable at 40 °C. Therefore, low-temperature storage is recommended for maintaining the quality and efficacy of hawthorn fruits and its preparations. 相似文献
127.
The relatively fast diffusion of Au atoms in eutectic PbSn matrix is considered one of the contributing factors to the Au
embrittlement problem. In this study, we further investigated the Au embrittlement problem in high-Sn solders. Experimentally,
Sn3.5Ag (wt.%) spheres with 500-μm diameter were soldered over the Au/Ni soldering pads. It was found that some of the AuSn4 needles that formed after reflow inside the solder migrated back to the solder/pad interface during thermal aging. However,
the migration kinetics in high-Sn solders was slower compared to that in eutectic PbSn. The difference in migration kinetics
of AuSn4 in eutectic PbSn and SnAg was ascribed to the difference in the magnitudes of the Au flux and the Ni flux. In eutectic PbSn,
the Au flux was much greater than that of the Ni flux, and the Au and Ni flux were in the same order of magnitude in eutectic
SnAg. The relative magnitude of the Au and Ni flux changed in eutectic PbSn and SnAg because the homologous temperatures of
PbSn and SnAg were different. 相似文献
128.
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