知识贝壳
知识贝壳
所属栏目：英汉双解生物技术与遗传工程
A secondary sewage-treatment process where biological processing of the sewage by microbial activity is the main method of treatment. In this step,sewage that has been previously treated in settling tanks is aerated in large tanks to encourage growth of m ......（本文共 702 字 ） [阅读本文] >>