【判断题】按GB16899-1997《自动扶梯和自动人行道的制造与安装安全规范》的规定,自动扶梯额定速度是指梯级在额定载荷下的运行速度。
【简答题】在吸收过程中,根据被吸收的组分数,可把吸收分为 ▲ 吸收和 ▲ 吸收;根据吸收质和吸收剂之间是否发生显著的化学反应,可把吸收分为 ▲ 吸收和 ▲ 吸收。
【单选题】Aunt Dotty loves adventure. On her 60th birthday, she went mountain climbing in the Alps. On her 70th birthday, she went on a trip to the North Pole. When she was 80, she drove solo across the United ...
A.
On her 60th birthday, she went mountain climbing in the Alps.
B.
On her 70th birthday, she went on a trip to the North Pole.
C.
When she was 80, she drove solo across the United States.
D.
She loves to eat chocolate.
E.
We all wonder what she will do when she is 90.
【判断题】分析天平分别称量两个物体,若两者的绝对误差相等,则相对误差也一定相等。
【判断题】吸收过程中吸收剂对吸收质要有较小的溶解度和较小的选择性。
【简答题】什么是临界热绝缘直径?平壁外和圆管外敷设保温材料是否一定能起到保温的作用,为什么?
【单选题】48 衰变常数λ反映了放射性物质的固有属性 ( )λ值越大,说明该物质越不稳定,衰变的越快
【判断题】自动扶梯额定速度是指梯级在额定载荷下的运行速度。