微生物肥料与化学肥料有什么不同?
微生物肥料有哪些种类?
当移动台通话时动态功率调整与时间接前量在哪个信道上传送() ["AGCH","TCH","SACCH","FACCH"]
在匹配的病例对照研究中,病例与对照的比例最常用()。 ["1:1","1:2","1:4","1:6","1:8"]
对于PHASE2+的MS在空闲状态下进行小区选择和重选的依据是() ["C1算法,C1算法","C2算法,C2算法","C1算法,C2算法","C2算法,C1算法"]
为什么在积液阶段不开下塔的液氮回流阀?