permagn.清洁金属用粉permn.电烫发v.电烫（头发）Permeation irrigation渗灌permafrost protection冻土保护permafrost embankment冻土路基permeability of ladle钢包透气性permeation experiment渗透实验permeation resistance抗渗permeability pressure渗透压力permeability-stress渗透率permonosulphuric acid过一硫酸Permethylpolysiloxane二甲硅油, 消泡净[消泡沫剂]