Quantitative IR spectrum and vibrational assignments for glycolaldehyde vapor: glycolaldehyde measurements in biomass burning plumes.
Quantitative IR spectrum and vibrational assignments for glycolaldehyde vapor: glycolaldehyde measurements in biomass burning plumes.
复制标题
乙醇醛蒸气的定量红外光谱和振动分配：生物质燃烧羽流中的乙醇醛测量。
DOI：
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发表时间：
2013
影响因子：
2.9
通讯作者：
Stephen D. Williams
中科院分区：
文献类型：
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作者：
T. Johnson;R. Sams;Luisa T. M. Profeta;S. K. Akagi;I. R. Burling;R. Yokelson;Stephen D. Williams
乙醇醛（GA，2-羟基乙醛，C2 H4 O2）是一种重要的半挥发性大气分子，最近被认为是形成水相二次有机气溶胶（SOA）的前体。有几种方法来测量GA蒸汽，但红外光谱法已成功地使用。使用经过审查的协议，我们已经完成了所有的基本振动模式的第一次分配，也得到了定量的红外吸收带强度使用净和压力加宽的GA蒸汽。即使GA是有问题的，由于其倾向于二聚和冷凝，我们的强度同意与以前公布的几个值。使用ν10波段Q分支860.51 cm（-1），我们还确定了GA混合比的生物质燃烧羽流所产生的现场和实验室燃烧的燃料从美国东南部和西南部，包括第一个红外现场测量烟雾中的GA。GA排放因子与确认GA从阴燃燃烧释放的修改后的燃烧效率呈反相关。GA的排放因子（克GA排放每公斤生物质燃烧的干质量的基础上）有一个低的依赖燃料类型与生产机制是纤维素热解一致。GA从野外火灾中以0.23 ± 0.13%的CO排放，我们计算出它占我们能够测量的水相SOA前体的1.18%。
Glycolaldehyde (GA, 2-hydroxyethanal, C2H4O2) is a semivolatile molecule of atmospheric importance, recently proposed as a precursor in the formation of aqueous-phase secondary organic aerosol (SOA). There are few methods to measure GA vapor, but infrared spectroscopy has been used successfully. Using vetted protocols we have completed the first assignment of all fundamental vibrational modes and also derived quantitative IR absorption band strengths using both neat and pressure-broadened GA vapor. Even though GA is problematic due to its propensity to both dimerize and condense, our intensities agree well with the few previously published values. Using the ν10 band Q-branch at 860.51 cm(-1), we have also determined GA mixing ratios in biomass burning plumes generated by field and laboratory burns of fuels from the southeastern and southwestern United States, including the first IR field measurements of GA in smoke. The GA emission factors were anti-correlated with modified combustion efficiency confirming release of GA from smoldering combustion. The GA emission factors (grams of GA emitted per kilogram of biomass burned on a dry mass basis) had a low dependence on fuel type consistent with the production mechanism being pyrolysis of cellulose. GA was emitted at 0.23 ± 0.13% of CO from field fires, and we calculate that it accounts for ∼18% of the aqueous-phase SOA precursors that we were able to measure.