Permaphase
带硅氧烷聚合物层的色谱固定相
🗣️ 情景例句
When will you be through with your homework?
你的家庭作业什么时候可以做完？
Excuse me to have kept you waiting.
对不起让你就等了。
Yes, it is. Why don't you take off your sweater?
是啊，你何不脱了羊毛衫呢？