By 1978, in the USA, the use of CFCs in aerosol propellants was banned.美国自1978年起禁止在喷雾剂压缩气体中使用含氯氟烃。This law closely resembles that obtained with conventional propellants.这种规律非常类似于用普通推进剂所得出的规律.The lighter version used liqu...
The lighter version used liquid hydrogen, the heavier used hypergolic propellants.较轻的推进器采用液态氢, 较重的采用自燃推进剂.Pressure - fed engines are particularly susceptible to dissolved gas in the propellants.挤压 式 发动机对推进剂中溶解的气体特别敏感.Thi...
先前所投入的人力物力可能会付诸东流.The resources previously committed might have been committed in vain.你也许要考虑等到你确实有了人力物力再独自采取这一措施.You might consider waiting until you do have resources to do it alone.这个建筑,耗用了不少人力物力.This architecture con...
There will moreover be a stipend of fifty pounds a year.每年还有五十镑一笔薪俸.This sum was nearly a third of his total stipend.这笔钱几乎是他全部津贴的三分之一。An absence without adequate excuse could result in the suspension of a financial stipe...