British Parliamentary procedure is perplexing at the best of times.即使在最好情况下，英国议会的程序也很费解。It took years to understand many perplexing diseases.许多疑难病症要耗时数年才能搞明白。This might seem very perplexing to those who know nothing abou...
Oxidized wax modified by amidation reaction to produce acylamide with better physical and chemical properties.氧化蜡经过胺改性可以得到具有更佳物化性能的脂肪酸酰胺.A new leather fatliquor product was synthesized by amidation, esterification and ne...