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101.
Highly transparent conductive Al2O3 doped zinc oxide (AZO) thin films have been deposited on the glass substrate by pulsed laser deposition technique. The effects of substrate temperature and post-deposition annealing treatment on structural, electrical and optical properties of AZO thin films were investigated. The experimental results show that the electrical resistivity of films deposited at 240 °C is 6.1 × 10−4 Ω cm, which can be further reduced to as low as 4.7 × 10−4 Ω cm by post-deposition annealing at 400 °C for 2 h in argon. The average transmission of AZO films in the visible range is 90%. The optical direct band gap of films was dependent on the substrate temperature and the annealing treatment in argon. The optical direct band gap value of AZO films increased with increasing annealing temperature. 相似文献
102.
103.
104.
Six new second order band-pass filter configurations using only a single current-controlled current differencing buffered
amplifier (CC-CDBA) are proposed. Further, the proposed filters also have a minimum number of external electronic components.
They realize current-mode, voltage-mode and transadmittance-mode filter characteristics. The quality factor and natural frequency
can be adjusted electronically without changing the values of the passive components. The proposed filters use a minimum number
of passive elements (two or three). There is no second order active filter structure which uses two passive components and
one active component in the literature. The validity of the proposed filters is verified through PSpice simulations. 相似文献
105.
Serkan Şimşek Sasan Ahdi Rezaeieh 《AEUE-International Journal of Electronics and Communications》2013,67(11):981-983
An efficient design method for substrate integrated waveguide electromagnetic bandgap (SIW-EBG) filters is proposed which provides direct dimensional synthesis approach for desired filter objectives without using network representations. The method is applied to the design of an X band SIW-EBG filter and its response is compared with HFSS (high frequency structure simulator) simulations for validation purposes. Fairly good agreement between the results shows the applicability of the proposed method for SIW-EBG filter design. 相似文献
106.
G.D. SkotisAuthor Vitae C. Psychalinos 《AEUE-International Journal of Electronics and Communications》2010,64(12):1178-1181
A voltage-mode Multiphase Sinusoidal Oscillator realized using Second Generation Current Conveyors and only grounded passive elements is introduced in this paper. The proposed topology is suitable for realizing oscillators with both odd and even number of phases without modifying the core of the topology. Only non-inverting Current Conveyors are required for the construction of the oscillator's topology and this is a benefit from the discrete component implementation point of view. The behavior of the proposed topology has been evaluated, through experimental results, in the cases of three and six-phase oscillators. 相似文献
107.
本文给出了强流相对论性电子束(IREB)在低压中性气体中传输特性的理论和实验研究结果。660kV,40kA,脉宽100ns的电子束注入充有H_2,N_2的漂移管,稳定的传输气压范围在(0.7-6.7)×10~2Pa间,传输效率可达80%以上;极低气压时(P≈13.3Pa)由于空间电荷效应,束电子被虚阴极阻滞并径向发散,不能有效传输;而较高气压时,束电子除受自身电磁场作用及库仑碰撞散射外,等离子体不稳定性使束流传输效率明显降低。用蒙特·卡洛法及数值解析法对电荷中和、电流中和过程进行了模拟计算并解释了实验结果。 相似文献
108.
P. Albella F. Moreno J.M. Saiz F. Gonzlez 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(8):1339-1346
The presence of small defects in micron-sized structured surfaces introduces small changes in the backscattering that can be assessed by means of an integrated parameter. In this work the influence of the optical properties of the substrate on this technique is analyzed for two different configurations: defect on the microstructure and defect on the substrate beside the microstructure. 相似文献
109.
托卡马克等离子体中的杂质会影响托卡马克的放电品质及等离子体特性。许多理论和实验对杂质的产生和输运做了深入详细的研究。等离子体电流起始阶段,由于约束性能不好,会引起大量的杂质产生,辐射损失增大是杂质增加引起的直接后果。杂质辐射是等离子体辐射的主要组成部分之一,等离子体线辐射功率~Z_(eff)~6,复合辐射功率~Z_(eff)~4,轫致辐 相似文献
110.
Souad Mokrane Laïd Makhloufi Nicolas Alonso-Vante 《Journal of Solid State Electrochemistry》2008,12(5):569-574
Conducting polypyrrole (PPy)/C (Vulcan XC-72) composite materials were synthesized by chemical polymerization method. These
materials were used as matrix to support platinum nanoparticles, which were produced by the carbonyl chemical route. For the
same catalyst loading (50 μg cm−2), it was observed that the nature of the composite strongly influences the electrochemical activity of nanoparticulated platinum
toward the oxygen reduction reaction in acid medium. The variation of the PPy/C ratio determines the so-called substrate effect
for electrocatalysis.
Dedicated to Prof. Dr. Teresa Iwasita on the occasion of her 65th birthday in recognition of her numerous contributions to
interfacial electrochemistry. 相似文献