东海近海水质无机氮类测定中的不确定度探讨

分析探讨了东海近海水质无机氮类测定中不确定度的影响因素。其中,考虑到海洋环境监测的一些特殊性,在建立评定不确定度分量的数学模型时,引入了重复性实验校正因子f,并选取2004年东海区海洋环境监测中不同海域的试样进行原始平行性测定资料,以A类方式评定量化重复性实验校正因子f的不确定度分量;同时,以A类或B类的方式对近海水质无机氮类测定中的其它各个不确定度分量进行了评定。结果表明,NH_4~ 测定的相对合成标准不确定度分量最大,重复性实验校正因子f是近海水质无机氮类测定不确定度的主要来源。在此基础上,计算了东海近海水质无机氮类(NO_2~-、NO_3~-、NH_4~ )测定中的相对合成标准不确定度分别约为0.080,0.034,0.10。

A Study on the Measurement Uncertainty of Inorganic Nitrogen in the Offshore Waters of the East China Sea

In the paper, the measurement uncertainty of inorganic nitrogen in the offshore waters in the East China Sea is discussed. Considering the specific characteristics in marine environment monitoring, the replicate-correctness-factor ( f ) is introduced when the mathematical model of estimating the components of measurement uncertainty is built, according to the data of ( 2004 ) the measurements of original parallel samples from the East China Sea, the replicate-correctness-factor ( f ) is estimated by identifying pattern A, the other components of measurement uncertainty of inorganic nitrogen were estimated by the identifying pattern A and pattern B. The results show that the relative combined standard uncertainty of ammonia measurement is the largest. The replicate-correctness-factor ( f ) is the main source of measurement uncertainty, and according to this, the relative combined standard uncertainty of nitrite, nitrate and ammonia measurements is calculated, and about 0.080, 0.034, 0.10 respectively.