1. The performance depends much on the linearity of the mixer used for up-conversion and the selectivity of filters. 性能在很大程度上取决于上变频所用混合器的线性以及滤波器的选择性。
2. A relationship between benzene conversion or products selectivity or energy efficiency and energy density was studied. 考察了苯的转化率、产物选择性、能量效率随能量密度的变化关系。
3. The key to the art of listening is selectivity. You stand guard at the ear —gateway to your mind, heart and spirit. You decide what you will accept. 有选择性是倾听艺术的关键。你把守着你的耳朵——你的大脑、心灵和精神的通道,决定自己接受什么样的信息。