国内外初中化学教材编写的比较研究

选取国内外有代表性的初中化学教材作为范例,从教材设计的背景中对教材编写理念、教材内容选取、教材内容组织方式、教材栏目和版面设计以及化学实验和习题设计等方面进行比较,并从5个维度得出现行国内外初中化学教材编写的共同特点。     

Degradation of pyrazinamide in aqueous solution by electron beam irradiation: kinetics,influence factors and mechanism study

The degradation of pyrazinamide (PZA) by electron beam irradiation (EBI) was studied. It was found that the degradation of PZA was efficient with the removal rate of 99% for 0.2 mM PZA under 5 kGy, and the degradation kinetics followed pseudo-first-order kinetics. The presence of CO₃^2?, HCO₃^?, NO₃^?, and fulvic acid inhibited the degradation of PZA. The addition of H₂O₂ or K₂S₂O₈ effectively enhanced the degradation and mineralization of PZA. The scavenger experiments and quantum chemical calculations showed that ^·OH was the primary reactive species in the degradation. The identification of intermediates and quantum chemical calculations illustrated the mechanism of degradation.