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【简答题】
用括号内所给动词的适当形式填空。 1. After a knock at the door, the child heard his mother's voice _____ (call) him. 2. It's no good _____ (waste) strength in shouting. 3. Our group is mainly concerned with bird _____ (conserve) in coastal areas. 4. He felt embarrassed with so many eyes _____ (focus) on his clothes he was wearing. 5. The children talked so loudly at dinner table that I had to struggle _____ (hear).
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【简答题】原子吸收光谱法适合哪些物质的分析?常见的原子化器主要有哪两类?各有什么特点?
【简答题】原子吸收光谱法具有哪些特点?
【简答题】原子吸收分析法其独有的分析特点是: 。非火焰原子吸收光谱法的主要优点是:
【单选题】以下哪个不是红外吸收光谱分析法的特点?
A.
应用范围广:除单原子分子及单核分子外,几乎所有有机物均有红外吸收;
B.
分子结构更为精细的表征:通过IR谱的波数位置、波峰数目及强度确定分子基团、分子结构;
C.
常用来做定量分析;
D.
固、液、气态样均可用,且用量少、不破坏样品;