运用CALPHAD技术,基于多组元多相复杂平衡体系的吉布斯自由能最小化原理,用大型集成数据库F A C T系统,考察了铝和氧化铁经典反应体系的热力学规律。针对材料的反应合成技术,计算了化学计量铝和氧化铁体系以及各种产物中物种的相变情况...运用CALPHAD技术,基于多组元多相复杂平衡体系的吉布斯自由能最小化原理,用大型集成数据库F A C T系统,考察了铝和氧化铁经典反应体系的热力学规律。针对材料的反应合成技术,计算了化学计量铝和氧化铁体系以及各种产物中物种的相变情况;分析了原料初始温度、配料比和SiO2含量对绝热温度和平衡组成的影响。展开更多
Mg/Al/Fe layered double hydroxide(MAF-LDH1) was prepared by solvothermal method with the sodium dodecyl sulfate as the template, and the ethanol system was benefit to growth of sample. The nature in the resulting MAF-...Mg/Al/Fe layered double hydroxide(MAF-LDH1) was prepared by solvothermal method with the sodium dodecyl sulfate as the template, and the ethanol system was benefit to growth of sample. The nature in the resulting MAF-LDH was investigated by X-ray diffraction, field emission scanning electron microscopy, Fourier transformed infrared spectra, thermogravimetric analysis, and N2 adsorption-desorption.The morphology of MAF-LDH1 is petal-like with the size of 400-500 nm and the thickness about 10-20 nm. The adsorption performance of the samples was evaluated by absorption of the Congo red(CR) solutions. Compared with Mg/Al layered double hydroxide(MA-LDH), the maximum adsorption capacities of the MAF-LDH1 samples were 943.4 mg/g which was greatly enhanced. Furthermore, after seven cycling tests, the adsorption performance was still up to 90%. Theoretical calculation results revealed that the adsorption process was spontaneous and followed the pseudo-second-order kinetic model and Freundlich model. This work provides a promising alternative strategy to enhance the adsorptive properties of hydrotalcite-like materials.展开更多
The 3D morphologies and growth mechanisms of proeutectic FeAl_(3) at the Al/Fe interface under different cooling rates were studied by synchrotron X-ray tomography.With increasing cooling rate,FeAl_(3) crystals develo...The 3D morphologies and growth mechanisms of proeutectic FeAl_(3) at the Al/Fe interface under different cooling rates were studied by synchrotron X-ray tomography.With increasing cooling rate,FeAl_(3) crystals developed from faceted polygonal prism,plates with flat surface,thin ribbon-like with periodic undulating surface to non-faceted rods with radial dendrites in cross section,indicating a gradual interface growth mode transition from two-dimensional layer growth to continuous growth.At a higher cooling rate,twinning mechanism plays a leading role in the formation and growth of FeAl_(3).A link between the morphologies,twinning and crystallographic structure was established based on quantitative analyses on the 3D structures.展开更多
文摘运用CALPHAD技术,基于多组元多相复杂平衡体系的吉布斯自由能最小化原理,用大型集成数据库F A C T系统,考察了铝和氧化铁经典反应体系的热力学规律。针对材料的反应合成技术,计算了化学计量铝和氧化铁体系以及各种产物中物种的相变情况;分析了原料初始温度、配料比和SiO2含量对绝热温度和平衡组成的影响。
基金Funded by the Science and Technology Development Plan Project of Shandong Province,China(No.2013GSF11714)the Open Project of Hunan Sustentation Fund:Key Laboratory of Applied Environmental Photocatalysis,China(No.ccsu-KF-1501)
文摘Mg/Al/Fe layered double hydroxide(MAF-LDH1) was prepared by solvothermal method with the sodium dodecyl sulfate as the template, and the ethanol system was benefit to growth of sample. The nature in the resulting MAF-LDH was investigated by X-ray diffraction, field emission scanning electron microscopy, Fourier transformed infrared spectra, thermogravimetric analysis, and N2 adsorption-desorption.The morphology of MAF-LDH1 is petal-like with the size of 400-500 nm and the thickness about 10-20 nm. The adsorption performance of the samples was evaluated by absorption of the Congo red(CR) solutions. Compared with Mg/Al layered double hydroxide(MA-LDH), the maximum adsorption capacities of the MAF-LDH1 samples were 943.4 mg/g which was greatly enhanced. Furthermore, after seven cycling tests, the adsorption performance was still up to 90%. Theoretical calculation results revealed that the adsorption process was spontaneous and followed the pseudo-second-order kinetic model and Freundlich model. This work provides a promising alternative strategy to enhance the adsorptive properties of hydrotalcite-like materials.
基金supported by the National Natural Science Foundation of China-Excellent Young Scholars(No.51922068)National Natural Science Foundation of China(Nos.51821001,51904186,and 51904187)。
文摘The 3D morphologies and growth mechanisms of proeutectic FeAl_(3) at the Al/Fe interface under different cooling rates were studied by synchrotron X-ray tomography.With increasing cooling rate,FeAl_(3) crystals developed from faceted polygonal prism,plates with flat surface,thin ribbon-like with periodic undulating surface to non-faceted rods with radial dendrites in cross section,indicating a gradual interface growth mode transition from two-dimensional layer growth to continuous growth.At a higher cooling rate,twinning mechanism plays a leading role in the formation and growth of FeAl_(3).A link between the morphologies,twinning and crystallographic structure was established based on quantitative analyses on the 3D structures.
