【单选题】(单选)有一外径为18mm的无缝钢管,管内通冷冻盐水,为减少冷量损失,在管外包一层导热系数λ=0.18W/(m·°C)的石棉,保温层外壁与空气对流给热系数α=10W/(m2·°C),比较石棉厚为5mm和8mm时的冷量损失:
【单选题】(单选)有一外径为18mm的无缝钢管,管内通冷冻盐水,为减少冷量损失,在管外包一层热导率λ=0.18W/(m·℃)的石棉,保温层外壁与空气对流给热系数α=10W/(m2·℃),比较石棉厚为5mm和8mm时的冷量损失()*
【单选题】有一外径为18mm的无缝钢管,管内通冷冻盐水,为减少冷量损失,在管外包一层热导率λ=0.18W/(m·°C)的石棉,保温层外壁与空气对流给热系数α=10W/(m2·°C),比较石棉厚为5mm和8mm时的冷量损失()*
【单选题】We found that the plane_____ when we got to the airport.
C.
was already taking off
【单选题】What a pity ! Considering his ability and experience , he ____better. A . need have done B.must have done C. can have done D . might have done
【单选题】有一外径为 18mm 的无缝钢管,管内通冷冻盐水,为减少冷量损失,在管外包一层热导率 λ =0.18W/(m · °C ) 的石棉,保温层外壁与空气对流给热系数 α =10W/(m2 · °C ), 比较石棉厚为 5mm 和 8mm 时的冷量损失( )
【简答题】在“体检中心”页面,可以很醒目的看到目前店铺急需处理的()()()和待跟进申诉等。
【单选题】What a pity! When we got to the cinema, the movie Let the Bullets Fly ______, so we saw only the end of it