The important fators which affect culture conditions of ? Halobacterium halobium ? B were screened by Plackett? Burman design.利用Plackett-Burman设计筛选出影响盐生盐杆菌( Halobacteriumhalobium )B培养条件的重要因素,然后利用正交试验设计对这些重要因素加以优化....
She was wearing the obligatory sweater and pearl necklace.她穿着那件经常穿的毛衣，戴着那串惯常戴的珍珠项链。When an end is lawful and obligatory, the indispensable means to is are also lawful and obligatory. (Abraham Lincoln , American statesman...