If we were able to build a perfect crystal, we should keep it at ________, otherwise defects would appear.

A. absouble zero
B. zero degrees Celsius
C. twenty-five degrees Celsius

固体在热力学上最稳定的状态是________。

A. 0K 时的状态
B. 0°C时的状态
C. 25°C时的状态

你认为研究晶体结构缺陷的意义是什么？举例说明。