大气中甲烷连续自动监测结果的不确定度评定  

Evaluation of the Uncertainties of Continuous Measurement for Methane in the Atmosphere

作　　者：崔虎雄 柴文轩 王颖 伏晴艳 CUI Hu-xiong;CHAI Wen-xuan;WANG Ying;FU Qing-yan(Shanghai Environmental Monitoring Center,Shanghai 200235,China;China National Environmental Monitoring Centre,Beijing 100012,China;Shanghai Chemical Environmental Protection Monitoring Station,Shanghai 200050,China)

机构地区：[1]上海市环境监测中心,上海200235 [2]中国环境监测总站,北京100012 [3]上海市化工环境保护监测站,上海200050

出　　处：《计量学报》2023年第8期1293-1297,共5页Acta Metrologica Sinica

基　　金：上海市科技计划项目(20DZ1204000,19DZ1205000)。

摘　　要：大气中甲烷浓度的持续增加引起的全球气候变化已成为世界共同面临的热点问题。为了精准研究环境空气中甲烷浓度变化特征和规律,评估甲烷测量结果的不确定度具有重要意义。基于在线气相色谱法测定大气中甲烷,对测量过程中产生不确定度的主要来源进行了分析,量化和评定各不确定度分量。结果表明:甲烷浓度为2000 nmol/mol时,其扩展不确定度为100 nmol/mol(取包含因子k=2,置信概率P=95%)。经分析发现,大气中甲烷在线测量的不确定度主要由标准气体稀释配制和标准曲线拟合所引入。The global climate change caused by the increase of methane concentration in the atmosphere has become a hot spot in the world.In order to accurately study the variation of methane concentration in the atmosphere,it is extremely important to understand and master the uncertainty of methane measurement.On-line gas chromatography is used to measure methane in the atmosphere,the main sources of uncertainty in the measurement process are analyzed,and each uncertainty component is quantified and evaluated.The results show that the expanded uncertainty is 100 nmol/mol(k=2,P=95%)when methane concentration is 2000 nmol/mol.According to the analysis,it is found that the uncertainty of online measurement of methane in the atmosphere are mainly introduced by the dilution and preparation of standard gases and the fitting of standard curves.

关 键 词：计量学 甲烷浓度 大气监测 在线气相色谱法 不确定度 

分 类 号：TB99[一般工业技术—计量学]