为了获得更好的脱硫效果,脱硫系统全部采用氧化锌脱硫剂进行脱硫。
参考答案:错
解析:氧化锌脱硫剂对有机硫吸收能力低,一般不能单独使用,而是与加氢催化剂串联使用。
It is several years since he ______ ill and his illness _______ great damage to his health. [ ]
A. fell; has done
B. fell; does
C. was; had done
D. felt; has done
变频调速所用的VVVF型变频器,具有()功能。
A、调压
B、调频
C、调压与调频
D、调功率