The hydrogenation can be controlled to produce any degree of hardness desired in the product.为了生产所需要的任何硬度的产品,可对氢作用加以控制.Its hydrogenation activity in aromatics saturation and ring opening activity were investigated.芳烃加氢饱和...
With a low-pitched rumbling noise, the propeller began to rotate.伴随着隆隆的低沉噪声，螺旋桨开始旋转起来。The engine turned a propeller.发动机使螺旋桨旋转起来。The freighter fouled its propeller in fishing nets.货船的螺旋桨被渔网缠住了。...
这本敏感的书谨慎、简洁地讨论了收养这一微妙问题。This sensitive book tackles the delicate issue of adoption with care and simplicity." 我们现在的防御工事距离市区只有一英里远."兰德尔队长简洁地说." Our present fortifications are only a mile from town,'said Captain Randa...