Liu Gang, Li Jiu-Hai, Wu Dan, Xu Hui
Huan Jing Ke Xue. 2014 Jan;35(1):73-8.
Wheat straws of six genotypes were burned under different conditions, and n-alkanoic acids in the straw and its smoke were measured by GC/MS. The results showed that the carbon number of the fatty acids in all the smoke ranged from C8 to C32. In the flaming smoke, the total amounts of the compounds varied from 1,509.3 to 10,543.7 mg x kg(- ), with a mean value of 5,871.2 mg x kg(-1). And the content ratio values of n-alkanoic acids with low carbon number (C8 to C16) to those with high carbon number (C17 to C32) (L/H) were between 0.8 and 5.3, with an average of 2.8. In addition, the mean values for C14/C16, C28/C16 and C30/C16 were 16.5%,14.1% and 11.4%, respectively. The distribution of the compounds in the smoke was bimodal with the peak carbon number of C16 followed by C28 or C30, and it showed an even carbon number preference. The mean values of carbon preference index (CPI) and average carbon chain length (ACL) were 19.8 and 18.2, respectively. In the smoldering smoke,the total amounts of the fatty acids were in the range of 5,799.3 to 37,244 mg x kg(-1), and the mean was 15,838.6 mg x kg(-1). Moreover, the L/H ratios varied from 1.2 to 5.6, with a mean value of 4.2. The average ratio values for C14/C16, C28/C16 and C30/C16 were 12.7% , 10.1% and 6.0%, respectively. The content distribution pattern of the compounds was similar to that in the flaming smoke, and the mean values of CPI and ACL were 24.7 and 17.7, respectively. In general, n-alkanoic acids in both wheat straw and its two types of smoke had similar distribution modes, both with even carbon number preference, but there was prominent distinction among the chemical compositions of the compounds in the straw and the smokes. This is maybe useful in identifying the organic matter from wheat straw or its smoke in the atmospheric aerosol.
对六种基因型的小麦秸秆在不同条件下进行燃烧，并通过气相色谱/质谱联用仪（GC/MS）测定秸秆及其烟雾中的正构烷酸。结果表明，所有烟雾中脂肪酸的碳数范围为C8至C32。在明火烟雾中，化合物的总量在1509.3至10543.7mg·kg⁻¹之间，平均值为5871.2mg·kg⁻¹。低碳数（C8至C16）正构烷酸与高碳数（C17至C32）正构烷酸的含量比值（L/H）在0.8至5.3之间，平均值为2.8。此外，C14/C16、C28/C16和C30/C16的平均值分别为16.5%、14.1%和11.4%。烟雾中化合物的分布呈双峰型，峰值碳数为C16，其次是C28或C30，且呈现偶数碳数偏好。碳偏好指数（CPI）和平均碳链长度（ACL）的平均值分别为19.8和18.2。在阴燃烟雾中，脂肪酸总量在5799.3至37244mg·kg⁻¹范围内，平均值为15838.6mg·kg⁻¹。此外，L/H比值在1.2至5.6之间，平均值为4.2。C14/C16、C28/C16和C30/C16的平均比值分别为12.7%、10.1%和6.0%。化合物的含量分布模式与明火烟雾中的相似，CPI和ACL的平均值分别为24.7和17.7。总体而言，小麦秸秆及其两种烟雾中的正构烷酸具有相似的分布模式，均呈现偶数碳数偏好，但秸秆和烟雾中化合物的化学组成存在显著差异。这可能有助于识别大气气溶胶中小麦秸秆或其烟雾中的有机物。
