Enclosures for protection against ionizing radiation Lead shielding units for 150 mm, 200 mm and 250 mm thick walls Part 1: Chevron units of 150 mm and 200 mm thickness???是什么意思_Enclosures for protection against ionizing radiation Lead shielding units for 150 mm, 200 mm and 250 mm thick walls Part 1: Chevron units of 150 mm and 200 mm thickness???在线翻译_英语_读音_用法_例句