共查询到10条相似文献,搜索用时 109 毫秒
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阐述ICP光源中射频功率测量的意义,提出了测量范围为100~1 500 W,频率为27.12 MHz的功率测量装置的设计方案。详细分析了射频功率测量装置中的电路设计,包括采样互感器、功率合成电路、幅度相位分析电路和移相电路,并给出了判断ICP光源负载状态和性质的方法。在实验中,利用BIRD43型功率计和BIRD4304A型功率计对射频功率测量装置进行了参数校准。 相似文献
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The electrochemical properties of neutral (dedoped) and oxidized (doped) poly(1,11‐bis(1,1‐pyrrole)‐3,6,9‐trioxaundecane) (poly‐ I ) film electrodes were investigated using cyclic voltammetry and electrochemical impedance spectroscopy (EIS) techniques. Poly‐ I was deposited on glassy carbon electrode (GCE) from acetonitrile solution containing 5.0 × 10?3M 1,11‐bis(1,1‐pyrrole)‐3,6,9‐trioxaundecane ( I ) and 0.1M LiClO4 supporting electrolyte. Doped poly‐ I exhibits a single semicircle in its complex‐capacitance plots, indicating a single dominant ion transport process, together with high capacitance values. These features make this polymer film a candidate for an energy storage material. Also, poly‐ I can be a candidate as a sensory material for the detection of Ag+ based on impedance parameters. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
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Multi-Walled Carbon NanoTubes (MWCNT) are ideally suited to be used for damage sensing in fiber reinforced composite materials, and are used for structural health monitoring in adhesive joints. In this work, the capability of MWCNTs for condition monitoring of a single lap Al-Al adhesive joints (SLJ) under shear load is studied using impedance measurements. Different weight percent of MWCNT, i.e. 2.5, 6 and 9 wt.% are added to epoxy adhesive. Epoxy adhesive containing 9 wt.% MWCNT is identified during shear loading to have the highest ultimate strength among the considered specimens and provide the best sensory properties. To provide a more concise evaluation of the damage progression in the adhesive layer under shear stress, artificial defects are inserted into the SLJ specimens. The effects of square and circular defects on the damage progression in the adhesive layer are studied. The results show that primary microcracks are initiated at and consequently develop from the defect boundary in the adhesive joints with larger size of defect. It was found that the shape of the defect does not have a significant effect on the impedance response and sharp resistance changes for specimens with circular and square defect areas of 70% overlap area were about 4.55 and 4.2% respectively. Additionally, when the crack grows entirely through the adhesive layer, a nonzero slope of the resistance change resulted even for low levels of shear displacement. 相似文献
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建立电涡流传感器的数学计算模型,使用Matlab编程求解线圈的等效电阻和等效电感。通过实验测试与模型计算值的对比发现,理论值与实测值间的误差较大,使得模型应用存在偏差。因此,提出一个适用于线径变化情况的修正函数对阻抗进行修正,结果表明:修正后理论值与实测值间的最大相对误差减小了10%左右。 相似文献
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基于DDS芯片的可控声源较其它的声源装置在信号精度以及信号转换速度上有比较大的提高,可以在声源定位系统、新型声纳等研究方面作为比较好的信号源. 相似文献
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D.E. Vladikova Z.B. Stoynov A. Barbucci M. Viviani P. Carpanese J.A. Kilner S.J. Skinner R. Rudkin 《Electrochimica acta》2008,53(25):7491-7499
This paper reports impedance studies of the cathode/electrolyte behaviour in solid oxide fuel cells (SOFC), based on comparative investigation of half-cells with yttria stabilized zirconia (YSZ) electrolyte and different cathode materials: lanthanum strontium manganite (LSM), and composite LSM/YSZ with low ionic conductivity as well as the electron conducting Ag, Pt and Au. For improved impedance data analysis the technique of the differential impedance analysis is applied. It ensures structural and parametric identification without preliminary assumptions about the working model. It is found that despite the low ionic conductivity of LSM, the cathode reaction of the oxide cathode materials is a two-step process including: (i) charge transfer with activation energy of the resistivity Ea increasing with the temperature and (ii) transport of oxygen ions through the bulk of the electrode (rate-limiting stage) with Ea independent on the temperature. For the metal (electron conducting) electrodes, the reaction behaviour is described with one step process with higher Ea at higher temperatures. The activation energy of the electrolyte conductivity decreases with the increase of the temperature. The observed changes in Ea for the electrolyte and the cathode reaction (the charge transfer step for the LSM-based electrodes) appear in the same temperature interval. This interesting coincidence suggests for correlation between the bulk (electrolyte) and surface conduction properties. Approaches for improvement of both the ionic conductivity and the supply with electrons in LSM should be also searched. 相似文献
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介绍基于脉冲测距技术的距离传感器,结合贵阳烟厂制丝线,阐述了其结构特点和使用方法,并对其应用前景作了描述。 相似文献
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Vitali P. Parkhutik 《Journal of Porous Materials》2000,7(1-3):97-101
The present work aims to study the AC impedance of porous silicon films left in the contact with the anodizing bath after their growth is over. It is shown that the layers grown at p-type silicon experience noticeable changes of their impedance behavior resulting in the gradual growth of electrical resistance of the p-PS layer. This change is assumed to be related with the deposition of a passive layer at the pore bottoms associated with reabsorption of dissolved Si-containing material from the electrolyte. The layers formed at n-Si also show changes of the electrical impedance, although they are much more complicated than in the previous case (dependence of the kinetics of changes on the polarization current and polarization time, presence of the inductive loops at the impedance spectra, etc. 相似文献