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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.

Han Y.-H.,China Tobacco Standardization Research Center | Han L.,Gansu Tobacco Industrial Co.
Chung-kuo Tsao Chih/China Pulp and Paper | Year: 2012

With the voice rising for resource saving and environment protection, there is a general trend of using vacuum metallization inner liner to replace with the composite aluminum foil paper for cigarette packaging. In this paper, we briefly introduced the quality protection capability, environment protection performance and machine adaptability of the vacuum metallization inner liner, technology, characteristic and identification method of the direct metallization paper and the transfer paper.

Ye C.-W.,Huazhong Agricultural University | Ye C.-W.,China Tobacco Standardization Research Center | Zhang X.-N.,Huazhong Agricultural University | Gao Y.-L.,Huazhong Agricultural University | And 3 more authors.
Analytica Chimica Acta | Year: 2012

This study presents the potential of multiple headspace solid-phase microextraction (multiple HS-SPME) for the quantification of analytes in solid samples. Multiple HS-SPME shares the same advantages as SPME. It also enables a complete recovery of the target compound and therefore the matrix effect, which commonly appears in SPME-based analysis, is avoided. A method based on multiple HS-SPME for the determination of the toxic contaminant ethyl carbamate (EC) in bread samples has been developed and validated, using gas chromatography with flame ionization detector. A novel polyethylene glycol/hydroxy-terminated silicone oil fiber was prepared for the first time and subsequently used instead of commercial ones because of its high extraction ability and good operational stability. An important problem still remained in multiple HS-SPME of EC in fresh bread samples. The adsorption of EC by water in the samples caused low transport of analyte to the headspace, which made multiple HS-SPME invalidated. Mixing with anhydrous sodium sulphate, the sensitivity of the method was improved and the problem was solved. The proposed method showed satisfactory linearity (0.15-1500μgg -1), precision (1.6%, n=5) and limit of detection (0.041μgg -1). Good recoveries, from 92.5 to 103.4%, were observed at three spiking levels. The method was applied to 14 bread samples. The multiple HS-SPME technique offers several advantages including reducing the manipulation time and cost, and avoiding analyte losses, especially in the analysis of a large number of samples in different matrices. © 2011 Elsevier B.V.

Yang K.,Chinese Academy of Sciences | Yang K.,Hefei University of Technology | Cui H.,Chinese Academy of Sciences | Li H.,Beijing Tobacco Quality Supervision and Testing Station | And 7 more authors.
Tobacco Science and Technology | Year: 2015

In order to accurately analyze the puff-by-puff release characteristics of CO in gas phase of mainstream cigarette smoke, an on-line puff-by-puff analysis system for cigarette smoke was established, which incorporated tunable diode laser absorption spectroscopy (TDLAS) technology with a modified single port smoking machine. The effects of cigarette smoke remained in pipeline and filter pad holder on the results of puff-by-puff analysis were analyzed with the system. The puff-by-puff release and transfer tendency of CO in mainstream smoke of cigarettes of four different types were analyzed. The results showed that: 1)The puff-by-puff transfer tendency of CO obviously differed before and after flushing the residual smoke from pipeline and filter pad holder. 2)Under the flushing mode, the puff-by-puff release of CO in mainstream smoke decreased at the first and second puffs then increased gradually with the minimum at the second puff. Comparing with traditional analysis methods, the modified single port smoking machine combined with TDLAS technology can complete the analysis of CO in cigarette smoke quickly and avoid the interference from other components in mainstream cigarette smoke effectively. © 2015, Editorial Office of Tobacco Science & Technology. All right reserved.

Yang L.,Zhongyuan University of Technology | Fan X.,Zhongyuan University of Technology | Zhang Q.,China Tobacco Standardization Research Center | Zhao H.,China Tobacco Standardization Research Center | And 4 more authors.
Tobacco Science and Technology | Year: 2014

In order to assess the cleaning effects of new flocked filter fabrics on the recirculated air from air conditioning system in cigarette manufacturing department, two fabrics of different types were tested and their influencing factors were analyzed. The results showed that: 1) The filtration efficiency of pile fabric was influenced by air velocity more significantly with a standard deviation of filtration efficiency distribution of 21.4%. The filtration efficiency of nap fabric was less affected by air velocity fluctuation, and its highest standard deviation of filtration efficiency distribution was 5.2%. 2) Dust concentration did not affect the running resistance of the two filtration fabrics significantly. 3) The average dust retentivities of nap fabric and pile fabric were 359.2 and 707.1 g/m2, respectively. Though lower in dust retentivity, nap fabric was considered to be more applicable due to its advantages of lower filtration resistance and higher stabilities of filtration efficiency and filtration resistance when air velocity or dust concentration fluctuated. ©, 2014, Editorial Office of Tobacco Science and Technology. All right reserved.

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