【单选题】在原子荧光分光光度计中,光源、原子化器和分光系统是排成()
【简答题】What mathematical concept is a relational database model based on?
【单选题】在原子荧光分光光度计中,光源、原子化器和分光系统是排成( )。
【简答题】在原子荧光光度计 中, ___________ 和检测器 呈直角放置,其目的是为了避免 ___________对荧光测定的干扰 。
【简答题】原子荧光法测定海水中汞的方法原理为:水样经硫酸过硫酸钾消化后,在还原剂硼氢化钾的作用下,汞离子被还原成单质汞。以氩气为载气将汞蒸气带入原子荧光光度计的原子化器中,以特种()为激发光源,测定汞原子荧光强度。
【单选题】What does relational argumentation concern?
A.
It concerns the nature and definition of things.
B.
It concern the relationship between things.
C.
It concerns the value or worth of things.
【单选题】What are the relationships that the relational database is named for?
A.
Relationships between entities
B.
Relationships between rows and columns
C.
Relationships between databases
D.
Relationships between fields and records
【简答题】某企业某年12月份发生以下经济业务,要求编制有关的会计分录:
企业以银行存款50000元偿还所欠供应单位的购料款。