Abstract：A new method for determining the moisture in gases by the cavity ring down spectroscopy is available to measure the concentration between 0.2×10-9 mol/mol and 20×10-6 mol/mol.A mathematical model is established for the uncertainty evaluation,and the results of the expanded uncertaunties are in the range of（8～20）×10-9 mol/mol （k=2, p=95%）.
周鑫,周泽义. 光腔衰荡光谱法测定气体中微痕量水不确定度评估[J]. 计量学报, 2012, 33(2): 178-180.
ZHOU Xin,ZHOU Ze-yi. The Uncertainty Evaluation of Determining the Moisture in Gases by the Method of Cavity Ring Down Spectroscopy. Acta Metrologica Sinica, 2012, 33(2): 178-180.
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2012, Vol. 33 
