用水滑石前驱体制备了Mg Fe O和Mg Fe Al O氧化物催化剂,研究了该催化剂在CO2气氛中乙烷脱氢催化活性。实验结果表明,添加Mg和Al元素有利于催化活性和乙烯收率的提高。MgFe0 5Al0 5Ox样品的活性较好,在700℃和V(CO2)/V(C2H6)=7时,乙烷...用水滑石前驱体制备了Mg Fe O和Mg Fe Al O氧化物催化剂,研究了该催化剂在CO2气氛中乙烷脱氢催化活性。实验结果表明,添加Mg和Al元素有利于催化活性和乙烯收率的提高。MgFe0 5Al0 5Ox样品的活性较好,在700℃和V(CO2)/V(C2H6)=7时,乙烷转化率20 6%,乙烯收率18 8%。CO2的作用是通过逆水煤气变换反应(CO2+H2 CO+H2O)推动乙烷脱氢反应并提高乙烯的选择性,通过CO2+C 2CO反应消除表面积炭提高催化剂的稳定性。展开更多
利用金相、X射线衍射(X-rays of diffraction,XRD)和扭摆内耗仪对固溶处理的冷却速度和Al质量分数对Fe-18Ga合金显微组织及阻尼性能的影响进行研究。结果表明,Fe-18Ga合金的阻尼性能随着固溶处理冷却速度的下降而升高。在Fe-18Ga合金中...利用金相、X射线衍射(X-rays of diffraction,XRD)和扭摆内耗仪对固溶处理的冷却速度和Al质量分数对Fe-18Ga合金显微组织及阻尼性能的影响进行研究。结果表明,Fe-18Ga合金的阻尼性能随着固溶处理冷却速度的下降而升高。在Fe-18Ga合金中以Al替代部分Ga,即替代体心立方Fe-Ga晶胞中Ga原子形成的置换式固溶,使材料中主要存在A_(2)相及少量有序的L1_(2)相。添加过多或较少的Al均无法形成可以钉扎合金磁畴或位错运动的有序相;而当添加Al的质量分数为3%时,对Fe-Ga合金的阻尼性能改善最为明显。展开更多
Nanometer powders of Al Fe alloy were prepared by gas evaporation. The formation regularity of the phases in the as prepared powders and the morphology of the particles were examined. The experimental results show tha...Nanometer powders of Al Fe alloy were prepared by gas evaporation. The formation regularity of the phases in the as prepared powders and the morphology of the particles were examined. The experimental results show that chemical composition of the master alloy is the key factor which controls the chemical composition of the compound phases in nanometer powders at given evaporating temperature, the compound phases with high Fe mole fraction will form with increasing of Fe content in master alloy. Only Al 13 Fe 4, FeAl 2 and Al 2Fe compound phases form in nanometer powders in present experiment, changing of the pressure of Ar can only alter relative amounts of the compound phases in the powders. Nanometer particles with inhomogeneous tissue were obtained, which is very different from that of pure Al and Fe nanometer particles. When mole fraction of Fe in particles increases, the inhomogeneity is enhanced. [展开更多
文摘用水滑石前驱体制备了Mg Fe O和Mg Fe Al O氧化物催化剂,研究了该催化剂在CO2气氛中乙烷脱氢催化活性。实验结果表明,添加Mg和Al元素有利于催化活性和乙烯收率的提高。MgFe0 5Al0 5Ox样品的活性较好,在700℃和V(CO2)/V(C2H6)=7时,乙烷转化率20 6%,乙烯收率18 8%。CO2的作用是通过逆水煤气变换反应(CO2+H2 CO+H2O)推动乙烷脱氢反应并提高乙烯的选择性,通过CO2+C 2CO反应消除表面积炭提高催化剂的稳定性。
文摘利用金相、X射线衍射(X-rays of diffraction,XRD)和扭摆内耗仪对固溶处理的冷却速度和Al质量分数对Fe-18Ga合金显微组织及阻尼性能的影响进行研究。结果表明,Fe-18Ga合金的阻尼性能随着固溶处理冷却速度的下降而升高。在Fe-18Ga合金中以Al替代部分Ga,即替代体心立方Fe-Ga晶胞中Ga原子形成的置换式固溶,使材料中主要存在A_(2)相及少量有序的L1_(2)相。添加过多或较少的Al均无法形成可以钉扎合金磁畴或位错运动的有序相;而当添加Al的质量分数为3%时,对Fe-Ga合金的阻尼性能改善最为明显。
文摘Nanometer powders of Al Fe alloy were prepared by gas evaporation. The formation regularity of the phases in the as prepared powders and the morphology of the particles were examined. The experimental results show that chemical composition of the master alloy is the key factor which controls the chemical composition of the compound phases in nanometer powders at given evaporating temperature, the compound phases with high Fe mole fraction will form with increasing of Fe content in master alloy. Only Al 13 Fe 4, FeAl 2 and Al 2Fe compound phases form in nanometer powders in present experiment, changing of the pressure of Ar can only alter relative amounts of the compound phases in the powders. Nanometer particles with inhomogeneous tissue were obtained, which is very different from that of pure Al and Fe nanometer particles. When mole fraction of Fe in particles increases, the inhomogeneity is enhanced. [
