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问题 单项选择题

属于五环三萜皂苷的是

A．羽扇豆烷型
B．羊毛脂甾烷型
C．螺旋甾烷型
D．联苯环辛烯型
E．异螺旋甾烷型

答案

参考答案：A

解析：五环三萜主要有齐墩果烷型、熊果烷型、羽扇豆烷型等。

单项选择题

能够检验封闭在高密度金属材料中的低密度材料是（）的独特优点。

A．X射线探伤

B．γ射线探伤

C．中子射线检测

D．超声检测
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听力题

B）根据短文内容及首字母提示，填写所缺单词。

It happens to most of us at times as we try to get through our workday. When sitting at work, we suddenly f  1   a bit headache. But don’t worry; there are some simple things that you can do to ease(减轻) a headache at work w  2   medicine.

Drink a bottle of warm water. Many people do not r  3   that the dry air in their working place can be a danger because of the lack(缺少) of water.

Eat a h  4   snack. During a busy day, it is easy to f  5   to eat, have a snack with much protein(蛋白质) which will improve your e  6   and quickly get rid of the hunger that is c  7   the headache. A cup of coffee or a piece of chocolate can be just the thing that you n  8   to ease your headache fast and get back on your way to a great day at work.

Step away from what you are working on for five to ten m  9  . Often, your headache is from your too much a  10   paid to one thing. This can be a computer screen or even one project. The best thing would be to go outside for your eyes to get some natural light.  
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