在晶体中存在杂质时对扩散有重要的影响,主要是通过(),使得扩散系数增大。
A. 增加缺陷浓度
B. 使晶格发生畸变
C. 降低缺陷浓度
说明本征扩散与非本征扩散的区别;正常扩散与反常扩散(逆扩散)的区别,并举出逆扩散的例子。
Part I··Structure··(10 minutes)Directions: This part is to test your ability to construct grammatically correct sentences.It consists of 2sections.Section A21. I am interested in the training course, which ___________at Hilton Hotel in Beijing from March 8 to 12,2018.
A)held
B) was held
C)will hold
D) will be held
22. In his paper, John is trying to identify___________determines the final result of the project.
A)what
B)whether
C)when
D) how