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Li Z.,China National Tobacco Quality Supervision and Test Center | Tang G.,China National Tobacco Quality Supervision and Test Center | Bian Z.,China National Tobacco Quality Supervision and Test Center | Feng Q.,Shanghai Tobacco Quality Supervision and Test Station | And 3 more authors.
Tobacco Science and Technology | Year: 2013

Reference material (RM) of nicotine purity was prepared. Six laboratories collaboratively confirmed quantitatively the purity of the prepared material by the method recommended by ISO 13276: 1997 "Tobacco and tobacco products-Determination of nicotine purity-Gravimetric method using tungstosilicic acid". The results showed that: 1) The purity of RM of nicotine was 98.5% with the expanded uncertainty of 0.6%. 2) The prepared RM featured good homogeneity test result and higher stability during investigating period, and satisfied the technical requirements of national second grade reference material. Source


Chen D.,Yunnan Tobacco Quality Supervision and Test Station | Li L.,Yunnan Tobacco Quality Supervision and Test Station | Peng L.,Yunnan Tobacco Quality Supervision and Test Station | Zhang Y.,Yunnan Tobacco Quality Supervision and Test Station | Li S.,Yunnan Tobacco Quality Supervision and Test Station
Tobacco Science and Technology | Year: 2015

In order to promote the accuracy of test results, the uncertainties in measurement of chromium (Cr), nickel (Ni), arsenic (As), selenium(Se), cadmium(Cd), and lead (Pb) in tobacco samples by inductively coupled plasma mass spectrometry (ICP-MS) were evaluated according to JJF 1059.1-2012 Evaluation and expression of uncertainty in measurement. The factors affecting the uncertainty were analyzed systematically with a cause-and-effect diagram, a procedure for assessing the uncertainty in the measurement was then developed, and the uncertainty of individual component was estimated with mathematic models. The results showed that: 1)The determined values for Cr, Ni, As, Se, Cd, and Pb were 1.41, 3.26, 0.42, 0.69, 1.97 and 4.11 μg/g, respectively; their expanded uncertainties at a confidence level of 95% were 0.10, 0.21, 0.03, 0.10, 0.13, and 0.33 μg/g, respectively. 2) The major factors influencing measurement uncertainty included recovery, repeatability, calibration curve fitting, and standard solution preparation. 3) The precision and accuracy of test results could be improved by preparing standard solution with gravimetric method, choosing a proper concentration range for standard working solution, and ensuring the stability of instrument by minimizing drift. © 2015, Editorial Office of Tobacco Science & Technology. All right reserved. Source

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