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Method of Measurement of Capacitance and Dielectric Loss Factor Using Artificial Neural Networks

., Sankaran, P., Sudhakar Rao, K. (2003). Measurement of C and tan δ of a capacitor employing PSDs and dual slope DVMs. IEEE Transactions on Instrumentation & Measurement , 52, (5), 1588-1592. [10] Cichy, A. (2013). Non-bridge circuit with double quasi-balancing for measurement of dielectric loss factor. IET Science Measurement & Tech nology, 7 (5), 274-279. [11] Roj, J. (2013). Neural approximation of empirical functions. Acta Physica Polonica A , 124 (3), 554-557. [12] Hornik, K., Stinchcombe, M., White, H. (1989). Multilayer feedforward networks are

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Microwave dielectric properties of BiFeO3 multiferoic films deposited on conductive layers

Abstract

Nondoped BiFeO3 (BFO) and doped Bi0.9La0.1Fe0.9Mn0.1O3 (BLFMO) thin films (d = 200–350 nm) were grown at 650–750 °C by RF sputtering on Si and SrTiO3(100), coated by conductive LaNiO3 films and La2/3Ca1/3MnO3/SrRuO3 bilayers. The complex dielectric permittivity of the films was measured at room temperature in the frequency range from 10 MHz to 10 GHz using parallel plate capacitor structures. Dielectric properties of the polycrystalline BFO films were compared with those of the epitaxial quality BLFMO films, and it was seen that the latter has better microwave performance than the former. The dielectric losses were below 0.05 at 1 GHz frequency, which may be acceptable for microwave applications.

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Investigation of dielectric properties of heterostructures based on ZnO structures

Abstract

The voltage and frequency dependence of dielectric constant є′, dielectric loss є″, electrical modulus M″, M′, loss tangent tanδ and AC electrical conductivity σAC of p-Si/ZnO/PMMA/Al, p-Si/ZnO/Al and p-Si/PMMA/Al structures have been investigated by means of experimental G-V and C-V measurements at 30 kHz, 100kHz, 500 kHz and 1 MHz in this work. While the values of є′, є″, tanδ and σAC decreased, the values of M′ and M″ increased for these structures when frequency was increased and those of p-Si/ZnO/Al and p-Si/PMMA/Al were comparable with those of p-Si/ZnO/PMMA/Al. The obtained results showed that the values of p-Si/ZnO/PMMA/Al structure were lower than the values of p-Si/ZnO/Al and p-Si/PMMA/Al.

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Influence of Bi2O3 addition on structure and dielectric properties of Ag(Nb0.8Ta0.2)O3 ceramics

Abstract

The structure and dielectric properties of perovskite Ag(Nb0.8Ta0.2)O3 ceramics were explored. A small amount of Bi2O3 was used to modify the dielectric properties of the ceramics. The addition of Bi2O3 led the ceramics to a high densification and optimal dielectric properties. With the addition of 4.5 wt% Bi2O3, the permittivity of Ag(Nb0.8Ta0.2)O3 ceramics increased from 470 to 733, the dielectric loss decreased from 62×10−4 to 6.7×10−4, and the temperature coefficient of capacitance, TCC, decreased from 2004 ppm/°C to −50 ppm/°C. The high permittivity obtained was due to the high densification and weak Ta-O or Nb-O bond strength in the oxygen octahedron that results from the addition of Bi2O3.

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Vibrational, electrical, dielectric and optical properties of PVA-LiPF6 solid polymer electrolytes

Abstract

Solid polymer electrolytes based on polyvinyl alcohol (PVA) doped with LiPF6 have been prepared using solution casting technique. Electrical properties of prepared electrolyte films were analyzed using AC impedance spectroscopy. The ionic conductivity was found to increase with increasing salt concentration. The maximum conductivity of 8.94 × 10−3 S·cm−1 was obtained at ambient temperature for the film containing 20 mol% of LiPF6. The conductivity enhancement was correlated to the enhancement of available charge carriers. The formation of a complex between the polymer and salt was confirmed by Fourier transform infrared spectroscopy (FT-IR). The optical nature of the polymer electrolyte films was analyzed through UV-Vis spectroscopy.

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Colossal dielectric constant of NaNbO3 doped BaTiO3 ceramics

the sample sintered at 1270 °C is 4.5 × 10 5 as shown in Fig. 2a , while the dielectric loss ( Fig. 2b ) is less than 0.2 at temperature range from −40 °C to 100 °C. For the sample of NN-BT sintered at 1250 °C, the dielectric constant is only half of the value of the sample sintered at 1270 °C, the temperature coefficient of capacity ∆C/C ranges from −15.4 to +16.7 in the temperature range of −40 °C to 90 °C and the dielectric loss is also almost half of the sample sintered at 1270 °C. When the sintering temperature is higher than 1270 °C, the dielectric constant

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Dielectric, etching and Z-scan studies of glycine doped potassium thiourea chloride crystal

.1 Dielectric studies The dielectric studies are vital to understand the electro-optic properties of crystalline material [10] for which the dielectric constant and dielectric loss of pure and glycine doped potassium thiourea chloride crystals have been evaluated at different frequencies using the Gwinstek-819 LCR cube meter at room temperature. To conduct good measurements, the parallel-faced single crystals were selected and covered by silver paste to avoid loss of data due to external factors. The active electronic, ionic, dipolar and space charge polarization

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Analysis of X-ray structure, dielectric properties and AC conductivity of (4E)-2-amino-3-cyanobenzo[b]oxocin-6-one

about bound (localized) electric charge carriers. This leads to good explanation and understanding of the electric and dielectric behavior of organic semiconductors [ 12 ]. The present work aimed to investigate the crystal structure of the powder of the (4E)-2-amino-3-cyanobenzo[b]oxocin-6-one, (4(E)-ACBO) using X-ray diffraction technique for the first time. The dielectric properties and AC electrical conductivity were analyzed for the bulk (4(E)-ACBO). The temperature and frequency dependence of dielectric constant, dielectric loss and AC electrical conductivity

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Structural, dielectric and AC conductivity studies on 0.8Ba0.2(Bi0.5K0.5)Ti1-xZrxO3 lead free ceramic system

the dielectric loss measured for all the Zr substituted samples as a function of temperature at different frequencies. Dielectric loss is decreasing with an increase of Zr content. Dielectric loss is higher at lower frequencies and decreases with an increase of frequency. It shows that at higher frequencies dipoles were unable to follow the applied AC field and hence, a decrease in dielectric loss at higher frequencies occurred [68, 11 ]. Zhi et al. [ 16 ] reported that dielectric constant value also depends on the density of the samples. The decrease in density or

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Synthesis, investigation on structural and electrical properties of cobalt doped Mn–Zn ferrite nanocrystalline powders

= 0.5 and −0.0008518 for x = 0.9 respectively. The strain results show that the strain changes from tensile to compressive nature with the increase in the cobalt content in the Mn–Zn ferrite. Fig. 6 W-H plot of Co x Mn y Zn y Fe 2 O 4 with (a) x = 0.1, y = 0.45 (b) x = 0.5, y = 0.25 and (c) x = 0.9, y = 0.05. 3.2 Dielectric properties The dielectric properties of Co x Mn y Zn y Fe 2 O 4 with x = 0.1, 0.5, 0.9 and y = 0.45, 0.25, 0.05 were studied using HIOKI 3532-50 LCR HITESTER. Dielectric loss, dielectric constant were computed according to

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