【判断题】【消耗次数：1】
低剂量照射紫外线，对微生物几乎没有影响，但以超过某一阈值剂量的紫外线照射，则会导致微生物的基因突变。
①
正确
②
错误
参考答案：
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阳光中的紫外线照射到皮肤上可生成( )。
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【单选题】
使用紫外线灯消毒时紫外线强度不低于（）
①
50μW/cm<sup>2</sup>
②
60μW/cm<sup>2</sup>
③
70μW/cm<sup>2</sup>
④
80μW/cm<sup>2</sup>
随机题目
【单选题】
当用光照射半导体时，打破了产生和复合的相对平衡，产生（）复合，在半导体中产生了非平衡载流子，半导体处于非平衡状态。
①
A.等于
②
B.少于
③
C.不超过
④
D.超过