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The discharge performance of antiferroelectric (AFE) capacitors is complicated and difficult to simulate due to the nonlinear polarization behavior of AFE. In this work, a nonlinear model for pulsed discharge AFEs was proposed based on a combination of the Preisach model and Kirchhoff's law. The model was driven by the data from first-order reversal curves and direct-current-bias (DC-bias) dielectric test measurements. Thus, the discharge behavior of the AFE can be studied without actual discharge experiments. Specifically, AFE discharge waveforms were calculated and evaluated for different size parameters and external circuit parameters that were conducive to compare the properties of different AFE materials. Moreover, the size effect of the capacitor on the discharge performance was discussed, which should draw the attention of researchers to prevent exaggerated conclusions. As a consequence, this method would fill the gap of AFE discharge simulation. [ABSTRACT FROM AUTHOR]

The effects of LiF addition on phase evolution, microstructure and dielectric properties of BaTiO based ceramics were investigated. The LiF addition lowered the sintering temperature of BaTiO based ceramics effectively from 1,380 to 1,100 °C. Orthorhombic-to-pseudocubic phase transition appeared as increasing sintering temperature or LiF content. Li dissolved in the lattice of BaTiO, replaced Ti site, produced oxygen vacancies and further inhibited the grain growth. F entered into O site, might cause weakening of oxygen bond strength, together with the low-melting-point liquid phase sintering of LiF, facilitated the formation of uniform dense and fine-grained structure and maintained good dielectric properties. Samples with 2 wt% LiF sintered at 1,100 °C showed excellent dielectric properties: ε = 1,956, tanδ = 0.8 % (at 1 kHz), ΔC/C < 10.44 % (−55-125 °C) and alternating current breakdown voltage E > 4.50 kV/mm. [ABSTRACT FROM AUTHOR]

Pb-doped In4-xPbxSe3 (x = 0.01-0.06) and Pb/Sn-codoped In4Pb0.01SnySe3 (y = 0.03-0.05) are prepared by solid state reactions of the elements (1223 K, 1 d, annealing at 753 K for 5 d). [ABSTRACT FROM AUTHOR]

The microstructures and dielectric properties of Y-Mg-Ga-Si co-doped barium titanate ceramics were investigated. Y 3+ dissolved in the lattice of BaTiO 3 replacing both Ba 2+ site and Ti 4+ site, and Mg 2+ replaced Ti 4+ site. The replacements of Y 3+ and Mg 2+ inhibit the grain growth, cause tetragonal-to-pseudocubic phase transition, reduce the dielectric loss, and flatten the temperature dependence of capacitance curve. The incorporation of Ga 3+ can improve sintering and increase permittivity. Y 3+ and Ga 3+ tended to remain close to the grain boundaries, and play an important role as a shell maker in the formation of the core–shell structure in the co-doped BaTiO 3 ceramics. Excellent dielectric properties: ϵ r = ∼2487, tan δ = ∼0.7% (at 1 kHz), ΔC/C 25 < ∼6.56% (from −55 °C to 125 °C) and alternating current breakdown voltage E < ∼4.02 kV/mm can be achieved in the BaTiO 3 –0.02Y 2 O 3 –0.03MgO–0.01Ga 2 O 3 –0.005SiO 2 ceramics sintered at 1380 °C. This material has a potential application in alternating current multilayer ceramic capacitor. [ABSTRACT FROM AUTHOR]

A simple and accurate method was developed for determining silicon in gasoline using inductively coupled plasma optical emission spectroscopy (ICP-OES). For sample inroduction a Burgener nubulizer and a Cyclonic spray chamber were used. A gasoline sample was diluted with isooctane and then introduced into the cooled spray chamber of the ICP-OES. Good linearity was achieved in the silicon concentration range 0.1 - 10.0 mg x kg(-1), and the correlation coefficient was 0.999 96. The detection limit for silicon was 0.012 mg x kg(-1) and the silicon recoveries from gasoline samples were 95.8% - 98.4%, with relative standard deviations of less than 3.0% The method was proved to be simple, reliable and highly sensitive, and suitable for determining silicon in samples of motor gasoline, ethanol-gasoline and methanol-gasoline fuel mixtures those containing not more than 15% (V/V) oxygenates.