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问题 单项选择题

PET探测原理是基于

A．湮灭辐射
B．韧致辐射
C．光电效应
D．康普顿效应
E．电子对生成效应

答案

参考答案：A

解析： PET技术的基础是正负电子“湮灭”所发出的成对光子的复合探测。

听力题

单词拼写（共10小题；每小题0.5分，满分5分）

小题1:If what you are teaching doesn’t a            to your students, they will lose interest in it.

小题2:The Hope Project is s              by wealthy big companies, who hope to advertise their companies or their products.

小题3:The height of the mountains v             from 1000 meters to over 2000 meters.

小题4:Some students think so many tests every week make them under a lot of s             .

小题5:I behaved badly yesterday and I am a            of myself now.

小题6:The film is a           from a novel with the same name.

小题7:After s             the water out of the skirt, she hung it in the sun.

小题8:He a               for this job, but was refused.

小题9:He worked very hard and e              his effort paid off in College Entrance Exam.

小题10:As we all know, smoking has many harmful e           on both smokers and non-smokers.
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单项选择题

一个小孢子母细胞或大孢子母细胞经过减数分裂形成（）个子细胞。

A.1

B.2

C.4

D.8
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