污水处理过程产生的浮渣及污泥如果不能有效地从系统分离出来,会对污水处理系统产生恶性循环。
参考答案:对
___in a heavy snow, the couple had to walk home, leaving their car behind.
A.Caught
B.Having caught
C.Catching
D.To catch
外周血中嗜酸粒细胞绝对值大于多少可诊断为嗜酸粒细胞增多症 ()
A.0.55×109/L
B.0.50×109/L
C.0.45×109/L
D.0.40×109/L
E.0.35×109/L