Five Co-B amorphous alloy catalysts were prepared by chemical reduction in different media, including pure water and pure ethanol as well as the mixture of ethanol and water with variable ethanol content, Their cataly...Five Co-B amorphous alloy catalysts were prepared by chemical reduction in different media, including pure water and pure ethanol as well as the mixture of ethanol and water with variable ethanol content, Their catalytic properties were evaluated using liquid phase furfural hydrogenation to furfuryl alcohol as the probe reaction. It was found that the reaction media had no significant influence on either the amorphous structure of the Co-B catalyst or the electronic interaction between metallic Co and alloying B. This could successfully account for the fact that all the as-prepared Co-B catalysts exhibited almost the same selectivity to furfuryl alcohol and the same activity per surface area ( Rs ), which could be considered as the intrinsic activity, since the nature of active sites remained unchanged. However, the activity per gram of Co ( R^mH ) of the as-prepared Co-B catalysts increased rapidly when the ethanol content in the water-ethanol mixture used as the reaction medium for catalyst preparation increased. This could be attributed to the rapid increase in the surface area possibly owing to the presence of more oxidized boron species which could serve as a support for dispersing the Co-B amorphous alloy particles.展开更多
研究了Al-0.5Mg-0.1Sn-0.1Si-0.02In合金作为铝空气电池的阳极材料,在2 mol/L Na Cl,4 mol/L Na OH乙醇-10%水,4 mol/L Na OH溶液中的腐蚀行为及电化学性能。结果表明,该合金在4 mol/L Na OH乙醇-10%水溶液中性能优良,具有较高的阳极利...研究了Al-0.5Mg-0.1Sn-0.1Si-0.02In合金作为铝空气电池的阳极材料,在2 mol/L Na Cl,4 mol/L Na OH乙醇-10%水,4 mol/L Na OH溶液中的腐蚀行为及电化学性能。结果表明,该合金在4 mol/L Na OH乙醇-10%水溶液中性能优良,具有较高的阳极利用率及较低的自腐蚀速率。腐蚀形貌及电化学阻抗谱测试结果与合金腐蚀特性一致。通过对比Zn在4 mol/L Na OH溶液中的电化学性能,Al-0.5Mg-0.1Sn-0.1Si-0.02In合金在4 mol/L Na OH乙醇-10%水介质中作为铝空气电池的阳极材料具有可行性。展开更多
基于乙醇/水溶液体系结晶纯化制备了Fmoc-L-亮氨酸.通过HRMS,IR和1 H NMR对该化合物进行了化学结构分析.被测化合物相对分子质量与Fmoc-L-亮氨酸理论相对分子质量一致,含有芴环、酰胺键和苯环等Fmoc-L-亮氨酸特征基团,其结构与目标化合...基于乙醇/水溶液体系结晶纯化制备了Fmoc-L-亮氨酸.通过HRMS,IR和1 H NMR对该化合物进行了化学结构分析.被测化合物相对分子质量与Fmoc-L-亮氨酸理论相对分子质量一致,含有芴环、酰胺键和苯环等Fmoc-L-亮氨酸特征基团,其结构与目标化合物的分子结构一致.展开更多
文摘Five Co-B amorphous alloy catalysts were prepared by chemical reduction in different media, including pure water and pure ethanol as well as the mixture of ethanol and water with variable ethanol content, Their catalytic properties were evaluated using liquid phase furfural hydrogenation to furfuryl alcohol as the probe reaction. It was found that the reaction media had no significant influence on either the amorphous structure of the Co-B catalyst or the electronic interaction between metallic Co and alloying B. This could successfully account for the fact that all the as-prepared Co-B catalysts exhibited almost the same selectivity to furfuryl alcohol and the same activity per surface area ( Rs ), which could be considered as the intrinsic activity, since the nature of active sites remained unchanged. However, the activity per gram of Co ( R^mH ) of the as-prepared Co-B catalysts increased rapidly when the ethanol content in the water-ethanol mixture used as the reaction medium for catalyst preparation increased. This could be attributed to the rapid increase in the surface area possibly owing to the presence of more oxidized boron species which could serve as a support for dispersing the Co-B amorphous alloy particles.
文摘研究了Al-0.5Mg-0.1Sn-0.1Si-0.02In合金作为铝空气电池的阳极材料,在2 mol/L Na Cl,4 mol/L Na OH乙醇-10%水,4 mol/L Na OH溶液中的腐蚀行为及电化学性能。结果表明,该合金在4 mol/L Na OH乙醇-10%水溶液中性能优良,具有较高的阳极利用率及较低的自腐蚀速率。腐蚀形貌及电化学阻抗谱测试结果与合金腐蚀特性一致。通过对比Zn在4 mol/L Na OH溶液中的电化学性能,Al-0.5Mg-0.1Sn-0.1Si-0.02In合金在4 mol/L Na OH乙醇-10%水介质中作为铝空气电池的阳极材料具有可行性。