Chalbot Marie-Cecile G, Chitranshi Priyanka, da Costa Gonçalo Gamboa, Pollock Erik, Kavouras Ilias G
University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States; University of Alabama at Birmingham, Birmingham, AL 35216, United States.
States Food and Drug Administration, Jefferson, AR, United States.
Atmos Environ (1994). 2016 Mar;128(March 2016):235-245. doi: 10.1016/j.atmosenv.2015.12.067.
The functional and C isotopic compositions of water-soluble organic carbon (WSOC) in atmospheric aerosol were determined by nuclear magnetic resonance (H-NMR) and isotope ratio mass spectrometry (IRMS) in an urban location in the Southern Mississippi Valley. The origin of WSOC was resolved using the functional distribution of organic hydrogen, δC ratio, and positive matrix factorization (PMF). Three factors were retained based on NMR spectral bins loadings. Two factors (factors 1 and 3) demonstrated strong associations with the aliphatic region in the NMR spectra and levoglucosan resonances. Differences between the two factors included the abundance of the aromatic functional group for factor 1, indicating fresh emissions and, for factor 3, the presence of resonances attributed to secondary ammonium nitrate and low δC ratio values that are indicative of secondary organic aerosol. Factors 1 and 3 added 0.89 and 1.08 μgC m, respectively, with the highest contribution in the summer and fall. Factor 2 retained resonances consistent with saccharides and was attributed to pollen particles. Its contribution to WSOC varied from 0.22 μgC m in winter to 1.04 μgC m in spring.
在美国密西西比河谷南部的一个城市地区，利用核磁共振（H-NMR）和同位素比率质谱（IRMS）测定了大气气溶胶中水溶性有机碳（WSOC）的功能和碳同位素组成。利用有机氢的功能分布、δC比率和正定矩阵因子分解（PMF）解析了WSOC的来源。根据核磁共振光谱箱载荷保留了三个因子。两个因子（因子1和因子3）在核磁共振光谱的脂肪族区域和左旋葡聚糖共振方面表现出强烈关联。这两个因子之间的差异包括：因子1中芳香族官能团的丰度，表明是新鲜排放；对于因子3，存在归因于硝酸氢铵的共振以及表明是二次有机气溶胶的低δC比率值。因子1和因子3分别贡献了0.89和1.08 μgC/m，在夏季和秋季贡献最大。因子2保留了与糖类一致的共振，归因于花粉颗粒。其对WSOC的贡献在冬季为0.22 μgC/m，在春季为1.04 μgC/m。
