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- Abstract： In this paper, a new high power and wideband amplifier with permanent periodic magnet(PPM) focusing is presented.It consists of klystron and FEM . 摘要： 提出了一种新的高功率宽带放大器，它由速调管和自由电子脉塞组成，用永久周期磁铁聚焦。
- That period was a bright page in the history of Chinese literature. 那个时期是中国文学史上光辉的一页。
- Let us hope that the period of this injustice will be over soon. 让我们希望这个不公正的时期很快结束吧。
- New strains of viruses appear periodically. 新菌系的细菌周期性地产生。
- Childhood is a period of rapid growth. 幼年是生长迅速的时期。
- He consulted the chronicles of the period. 他参考了这一时期的编年史。
- He had to decide within a given period. 他得在一定时间内作出决定。
- She has a detailed knowledge of this period. 她对这段时期的情况了解地相当详细。
- In that period auto sales hit a14-year low. 这时期汽车销售量达到14年来最低水平。
- In this period, unemployment reaches record levels. 这段时间的失业人数又达到了创纪录水平。
- Which period of history are you studying? 你正在学哪一段历史？
- In accordance with the effective mass theory, the magnetic Kronig-Penny potential was used to solve the electronic band structure of GaAs/Al?xGa? 1-xAs superlattice in a periodic magnetic field. 在有效质量理论近似下;采用磁Kronig-Penny势场;精确求解了GaAs/AlxGa1-xAs超晶格中的电子在周期性磁场中形成的能带结构.
- periodically magnetized 周期磁化
- The computed values of the periodic magnetic system containing the equivalent models by the 2D FEMM are in agreement with the measured results of the real system with open magnetic rings. 该2维等效模型能代替开口磁环进行计算。
- Can you tell me the time period when it was stolen? 能不能告诉我大概什么时候被偷的？
- Chaucer wrote in the late mediaeval period. 乔叟写作的时代是中世纪末。
- She'll be away for an indefinite period. 她将离开一段时间，何时回来未定。
- This was the most difficult period of his life. 这是他一生中最艰难的时期。
- The meeting finally came to a period. 会议终于结束了。
- A new high power and wideband amplifier with permanent periodic magnet focusing 一种新的永久周期磁铁聚焦的高功率宽带放大器
