以下不属于生产性噪声控制措施的是( )。
A.消除或降低噪声、振动源B.加强个人防护和健康监护C.消除或减少噪声、振动的传播D.采用水力清砂代替风铲清砂
参考答案:D
They usually have the medicine ______ before putting into the market all over the country. [ ]
A. testing out
B. to be tested out
C. being tested out
D. tested out
吸收塔大量带液不仅会造成(),而且会使甲烷化炉催化剂被()而失去活性。