铝及其合金加热时,会在表面生成Al2O3膜,但不会造成焊接时的熔合困难。
参考答案:错
短文填空。根据短文内容及首字母提示完成单词,补全短文。
There is a football match at Dalian S __1__ on W __2__. I would like to w __3__ it that afternoon
with my friend, David. There are some famous players (运动员) in the m __4__ . They are Anderson,
Lionel Messi and Kaka. Anderson is my f __5__ player. But my brother Mike doesn't want to to go with
us. He would like to go to the c __6__. The f __7__ is Rob-B-Hood (《宝贝计划》). It's a Jackie
Chan's film and Jackie Chan is my brother's favourite film s __8__ .
经化验白酒内含乙酸乙酯147mg/L,其阈值为0.0036mg/L,同时,酒中含有HEMF15mg/L,其阈值为0.00004mg/L,问在呈香上,谁大谁小,两者相差多少倍?