pin-point charge

例句：

1. 1. The scientist used a pin-point charge to detect the location of the virus.
   科学家使用一个精确的电荷来检测病毒的位置。
2. 2. The new device has a pin-point charge that can be charged quickly and released with precision.
   这款新设备有一个精确的电荷，可以快速充电并精确释放。
3. 3. The research team focused on developing a pin-point charge for use in medical imaging.
   研究团队专注于开发一种用于医学成像的精确电荷。