Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&...Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>.展开更多
To enhance sulfur adsorption and reactive activity, ordered mesoporous Cu-ZnO-Al2O3 adsorbents were prepared by a novel one-pot evaporation-induced self-assembly strategy using P123 as a structure-directing agent and ...To enhance sulfur adsorption and reactive activity, ordered mesoporous Cu-ZnO-Al2O3 adsorbents were prepared by a novel one-pot evaporation-induced self-assembly strategy using P123 as a structure-directing agent and ethanol as the solvent for reactive adsorption desulfurization. The metal oxide precursor molecules around P123 micellized, and self-assembly simultaneously occurred during evaporation from an ethanol solution at 60 °C, leading to the formation of the p6 mm hexagonal symmetry mesoporous structure. Characterization results prove that the Cu-ZnO-Al2O3 adsorbents possess an ordered mesoporous structure with high thermal stability, large surface area(386–226 m2/g), large pore volume(0.60–0.46 cm3/g), and good dispersion of ZnO and Cu, which is beneficial for transforming S-compounds to ZnO. The sulfur saturation capacity of the ordered-mesoporous-structure Cu-ZnO-Al2O3 adsorbents is larger(49.4 mg/g) than that of the unordered mesoporous structure(13.5 mg/g).展开更多
以纳米ZrO 、微米Al O 为原料,采用无压烧结方式制备了ZTA 复相陶瓷。结果表明:nano-ZrO 的 2 2 3 2加入有利于制备细晶ZTA 复相陶瓷。此外,nano-ZrO 的加入对 Al O 陶瓷的显微结构也产生影响,ZrO ...以纳米ZrO 、微米Al O 为原料,采用无压烧结方式制备了ZTA 复相陶瓷。结果表明:nano-ZrO 的 2 2 3 2加入有利于制备细晶ZTA 复相陶瓷。此外,nano-ZrO 的加入对 Al O 陶瓷的显微结构也产生影响,ZrO 颗粒以 2 2 3 2“晶内型”和晶界型两种形式存在。合理的配方组成及制备工艺有利于 Z r O 以四方亚稳相存在。Z r O 含量为 2 23 0 w t % 时,其四方相含量可达 6 9 %,有利于应力诱导相变增韧,该 Z T A 复相陶瓷的抗弯强度、断裂韧性分别达到 604MPa、6.87MPa·m1/2。展开更多
文摘Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>.
基金support by the National Natural Science Foundation of China(21676300)~~
文摘To enhance sulfur adsorption and reactive activity, ordered mesoporous Cu-ZnO-Al2O3 adsorbents were prepared by a novel one-pot evaporation-induced self-assembly strategy using P123 as a structure-directing agent and ethanol as the solvent for reactive adsorption desulfurization. The metal oxide precursor molecules around P123 micellized, and self-assembly simultaneously occurred during evaporation from an ethanol solution at 60 °C, leading to the formation of the p6 mm hexagonal symmetry mesoporous structure. Characterization results prove that the Cu-ZnO-Al2O3 adsorbents possess an ordered mesoporous structure with high thermal stability, large surface area(386–226 m2/g), large pore volume(0.60–0.46 cm3/g), and good dispersion of ZnO and Cu, which is beneficial for transforming S-compounds to ZnO. The sulfur saturation capacity of the ordered-mesoporous-structure Cu-ZnO-Al2O3 adsorbents is larger(49.4 mg/g) than that of the unordered mesoporous structure(13.5 mg/g).
文摘以纳米ZrO 、微米Al O 为原料,采用无压烧结方式制备了ZTA 复相陶瓷。结果表明:nano-ZrO 的 2 2 3 2加入有利于制备细晶ZTA 复相陶瓷。此外,nano-ZrO 的加入对 Al O 陶瓷的显微结构也产生影响,ZrO 颗粒以 2 2 3 2“晶内型”和晶界型两种形式存在。合理的配方组成及制备工艺有利于 Z r O 以四方亚稳相存在。Z r O 含量为 2 23 0 w t % 时,其四方相含量可达 6 9 %,有利于应力诱导相变增韧,该 Z T A 复相陶瓷的抗弯强度、断裂韧性分别达到 604MPa、6.87MPa·m1/2。