As2O5溶胶在电场中向正极移动,要使其发生聚沉,下列电解质中聚沉能力最强的是()。
A.NaCl
B.CaCl2
C.Na3PO4
D.Al2(SO4)3
参考答案:D
Everything comes with price;there is no such thing as free lunch in the world.
A.a,a
B.the, /
C.the, /
D.a, /
新品上市时,()是衡量市场效果的重要指标。
A.覆盖率
B.重需率
C.上柜率
D.动销率