Abstract：The principle of density measurement by hydrostatic weighing method and the characteristic formula of pure water density in volume measurement were analyzed, and the calculation formula of liquid density measured by solid standard of known density was deduced. The weighing method assigned a value to the solid density standard silicon sphere, and the relative measurement uncertainty was 3×10-6 (k=2). Finally, using a high-precision liquid density measuring device at 20℃, the density of the solid standard (silicon sphere) was transferred to the density of pure water by static weighing method. Compared with the Tanaka model, the En value was 0.059, and the comparison results were equivalent. The experimental results not only verify the high-precision liquid density measurement device, but also verify the theoretical value of the 20℃ pure water density model.
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2023, Vol. 44 
