【单选题】保温材料使用时的含水率,应( )。
A.
相当于该材料在当地自然风干状态下的平衡含水率
【单选题】材料处于( )状态时,测得的含水率是平衡含水率。
【判断题】如果用“肥田粉”[主要成分是(NH4) 2 S0 4 ]给农作物施肥,土壤的pH逐渐减小,请解释原因。
【单选题】材料处于 ( ) 状态时,测得的含水率是平衡含水率
【单选题】Who are most likely to be influenced by an innovation?
A.
people who didn't know about the innovation
B.
people who don't like the innovation
C.
people who like the innovation
D.
people who belong to a certain political party
【单选题】A market economy encourages innovation because:
A.
state ownership of enterprises reduces risks of innovation.
B.
economic freedom leads to greater incentives for innovation.
C.
government-owned and funded research centers become hubs of innovation.
D.
the prices of goods and services, including new products, are fixed by government.
【多选题】材料N在干燥状态的质量是8.8g,在自然状态(空气中)的质量是11g, 在吸水饱和状态的质量是13.2g,求材料N的平衡含水率和吸水率( )。