Abstract：The purifying device based on zone melting designed by the National Institute of Metrology (NIM) is described. The calorific primary reference material of benzoic is purified by the device. For improving the quality of highly purified sample,a new design of twin heater is employed. The crackle of glass tube due to inner tension is avoided by the new design of angle controller which can increase cross sectional area. The purity of benzoic is determined by the national primary standard instrument of coulometry. The result of benzoic purified by the device is 99.999%,which expanded uncertainty is 0.016 %(k=2). It proves the device meet the primary reference material requirements of purification.
孙国华, 李佳, 吴冰, 王海峰, 孟凡敏. 苯甲酸标准物质制备中区域熔融提纯装置的研制[J]. 计量学报, 2014, 35(2): 180-183.
SUN Guo-hua, LI Jia, WU Bing, WANG Hai-feng, MENG Fan-min. Development Purifying Device for CRM of Benzoic Based on Zone Melting. Acta Metrologica Sinica, 2014, 35(2): 180-183.
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2014, Vol. 35 
