使用液态氮作冷媒时，可将液氮直接喷向食品，使食品直接与-196℃的低温接触而快速冻结。
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根据制冷循环中制冷剂的冷却方式可以把冷水机分为水冷式冷水机和风冷式冷水机
A. 对
B. 错
After he failed in the business, he ended up ____ nothing to his name.
A. to have
B. have
C. had
D. having
Don't think they flew 90 billion light years to come down here and ___ a war.
A. begin
B. start
C. make
D. commence
The staff in the kitchen has ____ the message that a customer wanted a special dish.
A. ordered
B. accepted
C. pointed
D. received
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