电厂的热污染主要是指不采用()的直接水系统的温排水。
参考答案:冷却塔
I thought Father would be better, but _______it is, he is getting worse, which makes me more worried.
A.before
B.as
C.because
D.after
对膨胀烟丝()的要求为不低于98%。
A.长丝率
B.整丝率
C.碎丝率
D.纯净度