紫外-可见分光光度法测定没食子酸辛酯含量的不确定度评定

Evaluation of Measurement Uncertainty in Content Determination of Octyl Gallate by Ultraviolet and Visible Spectrophotometry

研究旨在建立紫外-可见分光光度法测定没食子酸辛酯含量的不确定度评定方法。利用紫外-可见分光光度法,构建没食子酸辛酯含量测定的数学模型,研究和量化不确定度来源,计算合成标准测量不确定度,给出扩展不确定度,得到不确定度报告。结果显示没食子酸辛酯含量为100.07%,标准不确定度为0.59%,扩展不确定度为1.18%,测量结果表示为(100.07%±1.18%),k=2。没食子酸辛酯含量测定的不确定度主要来源为吸光度的测定、供试品的称量、稀释体积以及测量重复性,要对仪器进行定期检定、维护和保养,实验过程中选用精度高且经过校准的玻璃量器,以降低测量误差。本次研究所建立的不确定度评定方法科学、完整、可靠,可为同法测定的不确定度评定提供参考,同时,也为有效控制没食子酸辛酯含量测定方法的准确性提供依据。

An evaluation method was established for the uncertainty of the determination of Octyl gallate by ultraviolet and visible spectrophotometry.By ultraviolet and visible spectrophotometry,a mathematical model for the determination of Octyl gallate was constructed,the source of uncertainty was studied and quantified,the synthesis and the expanded uncertainty were calculated and the uncertainty report was obtained.The results showed that the content of Octyl gallate was 100.07%,and standard uncertainty was 0.59%,and expended uncertainty was 1.18%,and the determination result was(100.07%±1.18%),k=2.The main sources of uncertainty in the determination of the content of Octyl gallate were the determination of absorbance,weighing of the test sample,dilution volume,and measurement repeatability.Regular calibration,maintenance and upkeep of the instrument were necessary,and high-precision and calibrated glass measuring instruments should be selected during the experimental process to reduce measurement errors.The established uncertainty assessment method was scientific,complete and reliable,which can provide reference for the evaluation of uncertainty in the same method of measurement,and also provide a basis for effectively controlling the accuracy of the content determination method of Octyl gallate.