A.適當(dāng)降低真空度B.適當(dāng)升高真空度C.適當(dāng)降低塔液位D.適當(dāng)升高塔液位
A.全封閉式葉輪B.閉式葉輪C.全開式葉輪D.半開式葉輪
A.濾紙B.濾布C.機頭布D.機尾布