MECHANISM AND KINETICS OF TRANSFORMATION OF ALUMINA INCLUSIONS BY CALCIUM TREATMENT

The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, experiments were performed by studying reactions between AltOs and CaO in a laboratory furnace and by performing calcium treatments in an 8kg induction furnace for Al deoxidised melt. The phases formed during the reaction between Al2O3 and CaO were examined by SEM-EDS （scanning electron microscope-energy dispersive spectrometer）, and the reaction sequence of Al2O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l） was discussed in term of the experimental observations. The kinetics of the reaction of calcium with alumina inclusions were simulated by immersing alumina plates in a Ca treated steel melt in the induction furnace. Results were compared with observations of real inclusion transformation. A kinetic model was proposed based on the results.

数字普惠金融与农业机械绿色之路

农业机械化是农业现代化的重要标志,农业机械化离不开绿色发展,降低农业机械的化石能耗、提升电力清洁能耗,是我国农业机械迈向绿色之路的重要方向。立足中国省际面板数据,选取农业机械的电力动能占比,表征农业机械的绿色化,实证检验数字普惠金融对农业机械绿色转型的影响与机制。研究表明:数字普惠金融显著提升我国农业机械的电力动能占比,数字普惠金融的覆盖广度、使用深度以及数字化支付程度,都推动农业机械绿色转型。对于涉农财政支出不足的地区,数字普惠金融促进农业机械绿色化的调节作用更明显,说明数字普惠金融弥补了涉农财政的资金缺口,通过金融互补机制助推农业机械绿色转型。对于经济落后地区和环境规制强度更高的地区,数字普惠金融推动农机绿色转型的效果也更突出。