研制了一种性能优异的易切削铋黄铜来替代有毒的铅黄铜.An environmental friendly Bi - brass with cutting - free and excellent properties was developed to substitute for Pb - brass....
The method was established for purification of diflubenzuron by crystal technique with mixed solvents.本文论述了利用混合溶剂——结晶法提纯除虫脲的分析技术.The separation and determination of the primary impurities of diflubenzuron by liquid chrom...
他现在拥有970家连锁食品店.He now owns a chain of 970 food stores.所有的元件严密地连锁在一起.All the units interlock with one another rigidly.这家超大型连锁加油站有各种名牌食品 、 洁净的卫生间 、 友好的服务并且结帐迅速.The hypermarket stations had a wide selection of branded foods...