If granulated tin is used the reaction may have to be initiated by careful warming.如果所用的是粒状锡,那么须靠小心加温来引起反应.When given cold setting , the granulated metal materials were obtained.同时配以相应的冷却条件,即能得到一种金属材料颗粒化的方法.Beat together...
Usefulness includes the fact the negatives have been calibrated.所谓有用,是指在底片上要有标度.The theory is of limited usefulness.这个理论用途有限。The report is of potential usefulness to the government.这个报告可能对政府有用。There are doubts about the ...