PPabbr.包裹邮递（=Parcel Post)abbr.过去分词（=past participle）abbr.邮资付讫的(=postpaid)n.一种中文文件交换软件和通讯软件PPEabbr.个人防护用品(=Personal Protective Equipment)abbr.(尤用于牛津大学)哲学﹑ 政治学和经济学(=philosophy；politics and economics)

1. The enhanced mechanism of PP fiber and polymer emulsion on cement mortar properties was explored.
   对聚丙烯纤维和聚合物乳液改性水泥砂浆的机理进行了初步讨论。
2. The paper introduces the anticlastic and water-tight performance of low content polypropylene fibre concrete.
   文章介绍了低掺率聚丙烯纤维混凝土的抗裂和抗渗性能。