化学分析中非线性曲线拟合结果的不确定度评定

Evaluation of uncertainty of non-linear curve fitting results in chemical analysis

为了评定非线性曲线拟合结果的不确定度,采用乘幂法将非线性曲线化为线性曲线,借助计算线性曲线拟合结果不确定度的一般公式来计算非线性曲线拟合结果的不确定度。评定过程及结果表明,此法简便易行,适用于2次及以上的高次曲线,可作为评定非线性曲线拟合结果不确定度的一般方法。

In order to evaluate the uncertainty of non-linear curve fitting results,the non-linear curve was transformed into linear curve by power algorithm.On the basis of the general formula of uncertainty of linear curve fitting results,the uncertainty of non-linear curve fitting results was calculated.The evaluation process and results showed that,the proposed method was simple and easy to carry out.It was applicable for the high order curve（quadratic and higher）,which could be used as the general method for the evaluation of uncertainty of non-linear curve fitting results.