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Bi0.5Na0.5TiO3 (BNT) is a lead-free ferroelectric ceramic that has received much attention in recent years. However, the pure BNT presents a tetragonal structure with considerable remanent polarization at room temperature, which lead to its low energy storage efficiency thus limiting its application in energy storage. In this paper, on the basis of the introduction of Ba0.3Sr0.7TiO3 (BST), NaNbO3 (NN) into BNT to form a relaxor ferroelectric, Gd2O3 is further doped to refine grain and reduce oxygen vacancy concentration thereby improving the breakdown strength, which is beneficial to improve its energy storage performance. A series of ceramic samples of 0.9 (0.5BNT-0.5BST)-0.1NN + xwt%Gd (x = 0, 0.5, 1, 2.5, 3) were prepared by the solid-state reaction method. The effect of Gd2O3 on the microstructure and electrical properties of the systems was investigated. The results show that a suitable doping level of Gd2O3 can significantly refine the grains and improve the breakdown strength of the system. For x = 2.5 ceramic sample obtained a high energy storage density of Wrec = 4.86 J/cm3 and an energy storage efficiency of η = 86% at 250 kV/cm. Furthermore, this sample exhibited a stable discharge density (Wd ≥ 1.44 J/cm3) and an ultra-fast discharge rate (t0.9 ≤ 0.056 µs) in the temperature range of 140 kV/cm, 40∼140 °C. [ABSTRACT FROM AUTHOR]

Spray-freeze drying (SFD) is a novel and advanced drying technology in the production of high-value foods and pharmaceuticals. However, long drying time is still a disadvantage for the SFD applications. This constraint could be alleviated using inert particles. This article provides the experimental results on SFD of whole milk in an integrated spray-freeze and vacuum freeze drying equipment. The effects were quantified in terms of the SFD drying time and the properties of the obtained milk powder in relation to the size of stainless steel balls used as inert particles. It is shown that the drying time could be reduced to some extent due to inert particles embedded and the milk powder of reduced size has high porous microstructure. [ABSTRACT FROM AUTHOR]

Abstract: The low-frequency internal friction Q −1 and relative shear modulus M of La2Cu1−x Ni x O4+δ (0≤ x ≤1) compounds were measured. For x ≤0.005, there are two relaxation internal friction peaks around 200 and 250K, both due to the hopping of the interstitial O atoms, while the peak located at lower temperature is invisible for 0.015≤ x ≤1. The 3D ordering process of interstitial oxygen occurs at x ≈0.5 (δ ≈0.082) and the fraction of the 3D ordering phase increases as a function of Ni content. [Copyright &y& Elsevier]

Abstract: Double-perovskite Gd1−x Pr x BaCo2O5+ δ membranes showed appreciable oxygen permeability at moderate temperatures. The overall oxygen permeation process of GdBaCo2O5+ δ was found to be controlled mainly by the bulk diffusion step with the membrane thickness larger than 0.8 mm, and the limitation by oxygen surface exchange came into play at reduced thickness of 0.8 mm. The electrical conductivity measurement showed Gd1– x Pr x BaCo2O5+ δ samples possessed a semiconducting behavior at a wide temperature range below 300 °C and a metallic behavior at 300–850 °C with a high conductivity of nearly 103 S cm−1. [Copyright &y& Elsevier]

Abstract: Composite membranes based on Ni and Zr-doped BaCeO3 are promising for hydrogen separation. Such composites show high proton conductivity and adequate chemical stability in H2O and CO2, but may be unstable in H2S. In this work, the hydrogen permeation performance of Ni–BaZr0.1Ce0.7Y0.2O3−δ was measured in an H2S-containing atmosphere at 900°C. The hydrogen permeation flux began to degrade in 60ppm H2S and decreased by about 45% in 300ppm H2S. After hydrogen permeation tests, X-ray diffraction analysis revealed the formation of BaS, doped CeO2, Ni3S2 and Ce2O2S. Analysis of the microstructure and phase composition, and results of thermodynamic calculations suggest that reaction between H2S and doped BaCeO3 caused the performance loss of the Ni–BaZr0.1Ce0.7Y0.2O3−δ . [Copyright &y& Elsevier]