He sat penitently in his chair by the window.他懊悔地坐在靠窗的椅子上。She had been sitting with her knitting at her fourth-floor window.她那时正坐在5楼的窗前织东西。She stared dreamily out of the small window at the blue horizon.她出神地看着小窗子外面的蓝色地平线...
以焦油苊为原料,研制萘酰亚胺型荧光 增白剂.Naphthoylimine Fluorescent Whitening Agent ( FWA ) can be made from tar - acenaphthene.目的: 了解泰安市面粉中增白剂的添加情况.Objective : To understand the brightening agent adding condition of flour in Taian.去污力强, 对...