I saw Louise walking slowly to the bus stop.我看见路易丝慢慢地走向公共汽车站。The three of them parted company at the bus stop.他们三个在公共汽车站分了手。He headed for the bus stop.他朝着公共汽车站走去。...
用各种稀的无机酸来萃取阴离子.A variety of dilute mineral acids are used to extract the anions.它对氟离子的选择性比其它普通阴离子高几千倍.It'shows a thousandfold selectivity for fluoride over other common anions.通常, 钙素过量是与该元素相联系的阴离子伴随产生的.In general, e...