Green ceramic material is a mixture of 60 wt % of clay, 10 wt % of calcite waste and 30 wt % of the clay fired at 1000°C for 90 min. The clay consists of 83 wt % of phyllosicates. The samples were undergone to XRD analysis, DTA, TGA, TDA and mf-TMA during heating 5°C/min. The mf-TMA was based on the measuring Young’s modulus by resonant method. The samples pass over several changes–release of the physically bounded water, burning of the organic impurities, dehydroxylation of kaolinite and illite, decomposition of calcite and creation of anorthite and mullite. The first visible increasing of Young’s modulus, which runs from room temperature to ~300°C, is a consequence of the release of the physically bounded water from pores, micropores and faces of crystals. In a temperature interval 450–650°C dehydroxylation of kaolinite and illite takes place, then decomposition of calcite runs between ~700 and 900°C. These three processes produce new structures which are mechanically weak because of significant part of micropores. In spite of that, Young’s modulus tends to slightly increase from 500 to 750°C and decreases only in a small extent during heating from 750 to 850°C. Then a steep increase of Young’s modulus values is recorded which can be ascribed to superposition of the solid-state sintering and creation of anortite at ~950°C and mullite above 950°C.

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Silica gel macrospheres were prepared from water glass as the silica source. The water glass solution was mixed with sodium alginate solution and added dropwisely to 1 M CaCl₂ solution to form macrospheres with ∼4 and 2.6 mm in diameter. Those SiO₂ macrospheres were soaked in 1:1 (volume) mixture of ethanol and 0.1 M Na₂HPO₄ to deposit hydroxyapatite layer (HAp-SiO₂ macrospheres). Bovine serum albumin (BSA) and egg lysozyme (LYZ) were adsorbed those SiO₂ and HAp-SiO₂ macrospheres. The amount of proteins adsorbed was well correlated to the Langmuir-type adsorption equation. The electrostatic interaction was predominant between the macrosphere surface and the protein molecules. Protein molecular entrapment in the mesopores (5–25 nm) was also probable for the SiO₂ macrospheres but not applicable to the HAp-SiO₂ ones without the mesopores. From consideration that protein molecule has a few groups with negative or positive partial charges, a multi-layer adsorption model was proposed.

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Joining of alumina with an alumina/zirconia insert by microwave heating was carried out at a low mechanical pressure of 0.17 MPa and high temperatures of 1650–1750°C. Joining occurred by diffusion bonding at 1650 and 1700°C, which are lower than the eutectic temperature of alumina/zirconia, and by liquid-phase assisted bonding at 1750°C, which is higher than the eutectic temperature of alumina/zirconia. Alumina joining under a low mechanical pressure and high temperature occurred successfully. Alumina joined at 1700 and 1750°C showed strengths of 310 and 212 MPa, respectively. Finally, joining by microwave local heating was demonstrated.

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Electric field-dependent permittivity of n-TiO₂ (rutile) along different crystallographic axes was investigated by an electrochemical impedance spectroscopy (EIS) measurement. The C⁻² versus U plots were fitted with a quadratic function of U, derived from a model that adds the effects of electric field dependent permittivity to the conventional Mott–Schottky equation. Only when atomically flat n-TiO₂ single crystal electrodes were used, could the intrinsic behavior of the electric field dependent permittivity be observed. The principal components of permittivity in the ab-plane exhibited a weak electric field dependence, while a strong electric field dependence was confirmed along the c-axis direction. By taking the electric field dependent permittivity into account, we were able to evaluate accurately the flat-band potential and the donor density. Different photocurrent behavior between (110), (100), and (001) electrodes is discussed in terms of the electric field strength at the surface and the depletion layer width within TiO₂.

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Porous silicon-bonded silicon carbide with tailored pore structure was prepared from silicon carbide, silicon, carbon, and boron powders as starting materials. Three different kinds of silicon particle sizes were used as pore formers, namely, fine (2.6 µm), intermediate (12.9 µm) and coarse (169.8 µm) while sintering temperatures varied from 1600 to 1800°C. These different processing conditions affected the characteristics of the prepared silicon-bonded silicon carbide (SBSC) which showed densities ranging from 1.65 to 1.95 g/cm³. Flexural strengths and gas permeability showed an inverse proportion, up to 70 MPa, 3.18 × 10⁻¹² m², respectively. Finally the effect of different silicon particle size and sintering temperatures on the gas permeability of silicon-bonded silicon carbide has been discussed.

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By introducing Ni ion into the B–site of perovskite lattice, (K_0.47Na_0.51Li_0.02)(Nb_0.94−xSb_0.06Ni_x)O₃ (KNN-LSN, x = 0, 0.002, 0.005, and 0.008) Pb-free piezoceramics were prepared by solid state reaction method. The effect of Ni doping amounts on the structure and electrical properties of KNN-LSN ceramics were investigated. XRD results showed that all ceramics had pure orthorhombic perovskite structure. The introduction of Ni ion into B–site of KNN-LSN ceramics effectively improved the electrical properties. The optimal electrical properties of d₃₃ = 192 pC/N, k_p = 38.6%, Q_m = 128, ε_r = 756, tan δ = 0.025, P_r = 25.6 µC/cm², and E_c = 1.21 kV/mm were obtained when Ni doping amount x = 0.005, indicating that this ceramic was a promising Pb-free candidate for practical use.

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CaMoO₄ and SrMoO₄ rods have been controllably synthesized by a simple sonochemical method without any surfactants at room temperature. The as-prepared powders were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). It was found that the ultrasonic time and Na₂MoO₄ and M(NO₃)₂ (M=Ca and Sr) molar ratio played a crucial role on the controllable synthesis of CaMoO₄ and SrMoO₄ rods. This route is proved to be convenient, mild and energy-efficient, and can be extended to the controllable synthesis of tungstates.

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Delta-alumina (δ-Al₂O₃) nanopowders and c-plane sapphires (α-Al₂O₃) were nitridated under a mixed gas flow of nitrogen and methane. The δ-Al₂O₃ nanopowders began to be converted to aluminum nitride (AlN) at 1300°C with phase transformation to α-Al₂O₃ but were not completely converted to AlN even after 10 h at 1600°C. The X-ray diffraction pattern and cross-sectional high-resolution transmission electron microscopy image of the nitridated sapphire showed the orientation relationship of AlN[0001]||Al₂O₃[0001] in the growth and the formation of an amorphous AlO_xN_y interlayer between the AlN layer and the sapphire substrate. This formation strongly supported the reaction mechanism in which Al₂O₃ converts to AlN through solid-state intermediates in the carbothermal reduction and nitridation reaction.

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