Reduction - metathesis method for preparation of strontium carbonate from celestite is developed.提出还原 - 复分解法制备碳酸锶的新工艺.Several kinds of ruthenium - catalyzed organic reactions were reviewed: hydrogenation, oxidation, isom...
你一定注意到他有时候显得特别疲惫。You must have noticed how tired he sometimes looks.他正挥手以引起他们的注意。He was waving his arms to draw their attention.罗斯听到了熟悉的声音，但没注意听说的是什么。Rose heard the familiar voice, but tuned out the words....
The two ends of the pipeline are connected with the radiator.管道的两端与暖气片相连接.The pipeline supplies Jordan with 15 per cent of its crude oil.该管道供给约旦15%的原油.A single pipeline serves all the houses with water.一条单管路给所有的房子供水....