Papers by Author: Hong Tao Jiang

Abstract: Pure Bi₁₂SiO₂₀ powder was successfully prepared by a molten salt method using Bi₂O₃ and SiO₂ as raw materials and using KCl-K₂CO₃ as flux at 635°C with the heating rate of 5°Cmin^-1. The phase composition and microstructure of these products were analyzed by X-ray diffraction and scanning electron microscopy, and the effects of the processing parameters, such as the ratio of Bi₂O₃/SiO₂, calciniation temperature, isothermal time and relative amount of salt, on the composition and particle size were investigated. The results indicated that regardless of changing the ratio of Bi₂O₃/SiO₂, calciniation temperature, isothermal time or relative amount of salt the reaction only yielded Bi₁₂SiO₂₀ without Bi₂SiO₅ and Bi₄Si₃O₁₂. Henceforth, KCl-K₂CO₃ molten salts may be considered as an ideal reaction medium to synthesize pure phase of Bi₁₂SiO₂₀. The particle size of Bi₁₂SiO₂₀ phase can be determined by changing the temperature, isothermal time and relative amount of salt.

Abstract: The ceramic company financial performance indicator has multilayers, many dimensions and intersect characters, and the comprehensive evaluation on it is a big challenge. Firstly, this paper introduces principal component analysis theory and tool. Secondly, it constructs the four-dimensional evaluating indicator system based on “debt-paying ability, operation capability, profitability, and development capability”. In the end, based on the financial report data, this paper conducts an empirical principal component analysis on 20 typical ceramic enterprises’ financial performance. The conclusion is that the ceramic business finance performance is mainly decided by four greatest factors including “debt-paying ability, profitability, efficiency, development” and the impact of the four greatest factors upon the finance performance degree is different. This research’s innovation lies in using the principal components method to give the weight to the evaluating indicators objectively, providing not only the new tool for the ceramic enterprise financial performance assessment method’s evolution, but also the new mentality for the ceramic enterprise financial performance’s improvement.

Abstract: In this paper, Ni_0.5Zn_0.5Fe₂O₄ferrite ceramics were produced with Ni_0.5Zn_0.5Fe₂O₄powders prepared by reaction in a molten salt using Fe₂O₃, NiO and ZnO powders as raw materials. Ni-Zn powders were characterized by X-ray diffraction (XRD). Density and shrinkage in diameter of Ni_0.5Zn_0.5Fe₂O₄ceramics were measured. MicroSubscript text structures were observed using field emission scanning electron microscopy (FESEM), and magnetic properties were examined by HP4291B impedance analyzer. XRD pattern indicated that the powders synthesized at 900°C for 1h were pure spinel Ni_0.5Zn_0.5Fe₂O₄phase. Via the measurement of density and shrink in diameter, optimal temperature was 1200°C and holding time was 2h, which was in accord with the results concluded from micrographs. FESEM images illustrated that the average grain size increased with increasing holding time, which followed the Ostwald liquid growth mechanism. At lower frequencies, the initial permeability (μ_i) increased from 86.65 to 183.48 with increasing holding time, while the threshold frequency decreased from 13.3MHz to 8.52MHz, which implied the initial permeability (μ_i) variation complied with the Snoek law to some extent.