精馏中出现液泛主要是由于气相负荷大,气相负荷主要是通过()来降低。
A、提高精馏温度
B、降低精馏温度
C、提高回流比
D、降低回流比
参考答案:B
词语辨析。
A)用because of, because填空
1.____the bad weather, they had to have their P.E. lessons indoors.
2. He won't come ____ he has been informed of the change of the meeting.
B)用a number of, the number of填空
3. All the members were present, but ____ them left earlier for different reasons.
4. Since then ____ people learning English has been increasing rapidly.
C)用even if, as if填空
5.____ I have to sell my house, I'll keep my business going.
6. The stranger is talking ____ he knows everything about the plan.
D)用specially, especially填空
7. My little sister often catches cold, ____ in early spring.
8. I bought this chocolate cake ____ for your birthday.
生产1m3石灰膏需生石灰( )kg。
A.320
B.560
C.630
D.660