Papers by Author: Shou Zhi Yi

Abstract: The better appearance of LCD rare earth polishing powder, the better sales. High-performance polishing powder for LCD was synthesized by using NH₄HCO₃ subsidence method, with rare earth carbonate as starting material. Coloring mechanism of rare earth polishing powder was studied by using TGA, XRD and so on. Color of rare earth polishing powder was quantitative described with the values of L, a, b, R, and chemical composition had a great influence on it. The result showed that Ca, Mg, Zn, Mn, P, Fe, Cu had a great effect on the white color of rare earth polishing powder, and the color had regular changes with chemical composition, calcining temperature, calcining time. The result can control production of rare earth polishing powder based its color, and it has significant practical value to color control of rare earth polishing powder.

Abstract: The advanced pretreatment by electrolysis of Bohai seawater in Tianjin used a diaphragm electrolyzer in the experiment. Removal efficiency and influence factors of the method were analyzed. Results show that turbidity, organic compounds, SDI and chroma of seawater were effectively decreased by electrolysis. Removal efficiency was significantly increased by current density, operation time and inter-electrode distance, and the optimum electrolytic conditions was determined as inter-electrode distance of 2 cm, current density of 15.87 mA·cm^-2, operation time of 10 minutes. It was investigated that when the water quality after electrolysis was of pH 8.6, the chroma and turbidity decreasing trend slowed down, with chroma of 0.052 A, removal rate reached 88.4%; the residual turbidity reduced to 2.52 NTU, removal rate reached 90.71%. A PH of about 8.5, COD_Cr decreasing trend slowed down, and when COD_Cr < 750 mg/L, it conformed to the requirements of the reverse osmosis water.

Abstract: Polishing powder based on CeO₂ is synthesized by a neutral precipitation method under the action of an additive, with Ce₂(CO₃)₃ as starting material and NH₄HCO₃ as the precipitant. The size distribution of CeO₂ particles is narrow-ranged and their morphology show a shape of polyhedral globules. They have a satisfied dispersion in water. The optimum characteristics are obtained under the conditions of followings: the mass ratio of F (in H₂SiF₆ ) to CeO₂ 7%, the molar concentration of additive A4 0.85mol/L, calcined at 850°C for 2 hours.

Abstract: Alkalizer or coagulation and alkalizer technology were adopted to pretreat seawater in the study. Turbidity removal was investigated with different pH, mixing time,and mixing speed. The A was the best by contrasting alkalizer A, B and C. Turbidity removal was 99.4%. The effect of boron removal in the seawater was also studied. The results showed that the pH value has a great impact on the boron removal. The highest boron removal was 89% by alkalizer A under pH 11.The best reaction condition for turbidity removal : pH value 10.8,stirring rate 200r/min,reaction time 10 minutes and dosage of PAM 0.5 mg/L.

Abstract: The inhibition effects of sodium silicate, phytic acid and their mixtures in 5% NaCl solutions have been investigated using weight loss method and Tafel polarization techniques. The surface morphology of carbon steel was obtained using scanning electron microscopy (SEM). The results show that the co-addition of 70 mg∙1^-1 sodium silicate and 5 g∙1^-1 phytic acid has the optimum inhibition efficiency (84.15%) and the lowest corrosion rate (0.13 g∙m^-2∙h^-1). Compared with their individual inhibition effects, the optimum inhibition efficiency of sodium silicate is 62.17% at 90 mg∙1^-1 and phytic acid is 80.05% at 15 g∙1^-1, respectively. The results obtained from weight loss method and Tafel polarization curves are in good agreement. The results show the enhanced inhibition effect by the inhibitors mixtures.