题目内容

使用60.0 MHz NMR仪器时，TMS的吸收与化合物中某质子之间的频率差为240 Hz，若使用500.0 MHz NMR仪器时，它们之间的频率差为多少？该质子的化学位移δ值是多少？

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某化合物的两个氢核HA和HB的化学位移δ分别为1.2和1.0（所使用的仪器300.0 MHz 1H NMR）,它们之间的耦合常数为JAB=20Hz, 请指出A和B两个氢核构成什么自旋体系，是否属于一级裂分，并解释原因。

Task 1 : There are five short dialogues about humans and animals. Listen carefully, and choose the best answer to each question.Q: According to the man, what do dogs and humans have in common?[音频]

A. They share similar emotions.
B. They are both cute.
C. They both miss the woman.
D. They can tell what the other is feeling.

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Task 1 : There are five short dialogues about humans and animals. Listen carefully, and choose the best answer to each question.Q: What does the woman think makes us different from animals?[音频]

A. Our ability to walk upright.
B. Our ability to talk.
C. Our ability to think.
D. Our ability to self-reflect.

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Task 1 : There are five short dialogues about humans and animals. Listen carefully, and choose the best answer to each question.Q: What is the popular belief about animals?[音频]

A. That they can form deep loving bonds with each other.
B. That we have a lot more in common with animals than we thought.
C. That they cannot form deep loving bonds with each other.
D. That we should have deep loving relationships with them.

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