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| Study on Air Density Measurement for Measuring Weights |
| WANG Xiao-lei,WANG Jian,ZHONG Rui-lin,ZHANG Yue,CAI Chang-qing,YAO Hong,DING Jing-an |
| National Institute of Metrology, Beijing 100013, China |
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Abstract To determine air density for high accuracy measurement of the weights, the method using the recommended equation is studied. According to the CIPM-2007 equation, an equipment of air density measurement that for high accuracy measurement of the weights is developed. Measurement of temperature, humidity, pressure and CO2 are integrated on it to measure air density automatically. Comparing with the results using approximation formula for air density, the relative error of 0.022% is achieved when CO2 is 937.4×10-6. The experimental results prove that additional measurement of CO2 can improve accuracy of air density measurement.
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2011, Vol. 32 
