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8572618 
Journal Article 
Apparatus for accurate determination of dynamic melting point organic reference materials 
Wang, HF; Sun, GH; Li, J; Ma, K; Zhao, M 
2010 
31 
5 A 
37-41 
Chinese 
A capillary type melting point apparatus with the vacuum adiabatic vessel is developed for the determination of dynamic melting point of organic substances. A high accuracy is achieved due to the reduction of systematic errors from the temperature gradient and the thermal lag of thermometer. This apparatus is applied in the determination of eight certified reference materials including lauric acid, biphenyl, imidazole, acetanilide, phenacetin, 4-methyl benzoic acid, anthracene and carbazole. The expanded uncertainty of dynamic melting point is 0.20°C and 0.17°C at the rate of 1.0°C/min and 0.5°C/min. Furthermore, these results are compared with those by an improved differential scanning calorimetry (DSC) method. The difference of the results of two methods is less than 0.23°C. The consistency of two methods also validates the accuracy of this apparatus. 
Capillary melting point apparatus; Differential scanning calorimeter; Dynamic melting point; Metrology; Reference materials; Uncertainty