About DING Dayu
About HIGAKI MORIMASA
About OKI YUZO
About YOSHIDA TADAO
About Science and Technology of Energetic Materials
About blasting supplies
About projectile
About steel pipe
About pressure sensor
About pressure fluctuation
About launching
About fireworks
About pressure increase
About Hobby and amusement goods
About 打揚
About 煙火
About 筒内圧力
About 打上げ