2. its use in flash lamps for high-speed photography.作从句的主语,因为太长所以置后,还原后为,among which its use in flash lamps for high-speed photography may be mentioned.
2. its use in flash lamps for high-speed photography.作从句的主语,因为太长所以置后,还原后为,among which its use in flash lamps for high-speed photography may be mentioned.