2018/06/11 16:46
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产品配置单:
科捷通用气相/GC5890N气相色谱仪
型号: GC 5890N
产地: 江苏
品牌: 南京科捷
¥3万 - 5万
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方案详情:
目前,防冻液质量的优劣主要通过以下两点来衡量:首先是防冻液效果,另一个是防冻液的沸点。乙二醇是一种无色微粘的液体,沸点是197.4℃,冰点是-11.5℃,能与水任意比例混合。混合后由于改变了冷却水的蒸汽压,冰点显著降低。其降低的程度在一定范围内随乙二醇的含量增加而下降。当乙二醇的含量为68%时,冰点可降低至-68℃,超过这个极限时,冰点反而上升。为了控制防冻液的质量,一些发达国家都规定了质量标准和相应的评定方法。根据美、日及中国相关的防冻液标准,对防冻液的各项评定项目主要有:抗冻性(冰点)、金属腐蚀性、发泡性、水泵气穴腐蚀性、沉淀性(灰分)、溶解性、密度、酸度值(PH值)、储备碱度、变色性、沸点等。但对其中的乙二醇含量分析的文献未见报道。本实验采用气相色谱内标法对防冻液中乙二醇的含量进行了测定。
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