A number of vertical line sources was generally caused by catalytic agents, dispersed from falling pyrotechnical flares of an airplane or a rocket.

下投式飞机和火箭焰弹分散的催化剂一般都形成若干条垂直线源。

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The influence of the oxygen balance of pyrotechnical combustion agent and the structure of its rare earth metal shell on the burning performance of the combined combustion element were studied.

分析了烟火燃烧剂的氧平衡及稀土壳体的结构对复合燃烧元件燃烧性能的影响，提供了复合燃烧元件的各项物化性能数据。

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However, these pyrotechnical feats came at a price.

WSJ: When Two Makes Perfect | By Byron Janis

The National Capital Commission's (NCC) Guy Laflamme, one of the festival's organizers, said the opening will be "bigger than ever" featuring "a huge cascade of pyrotechnical effects" pouring from the Alexandra Bridge into the icy river.

BBC: Embracing winter in Ottawa