protective gas保护气体protectiveadj.保护的；防卫的protective reaction of antibody抗体保护反应protective clothing for welders焊接服protective preparation for meta金属保护制剂protective atmosphere equipment保护气氛供应设备protective coatings for chassis底盘护理涂料Protective Integrated Hood MaskProtective range of an arrester避雷器的保护范围protective clothing of asbestos石棉防护服或金属防护protective atmosphere annealing保护气氛退火protective pillar against water防水安全煤岩柱