四氯乙烯 AR,98%,GR,99.5%,99%(分子筛、 Water≤50 ppm),色谱级, ≥99.0%,红外分析用,环保级,99.5%(GC)(标准试剂),光谱纯,≥99%,红外测油仪专用,≥99.8%