中国近海大气气溶胶中有机胺的浓度分布及来源

发布时间：2018-05-01 09:34

本文选题：中国近海 + 有机胺　；参考：《中国海洋大学》2015年硕士论文

【摘要】：利用2013年3-4月南海、5月东海、6-7月黄渤海、8月东海以及10月东海五个航次采集的57套Anderson分粒径气溶胶样品,分析其中有机胺的浓度,探讨了中国近海大气气溶胶中有机胺的种类,浓度分布,粒径分布及其主要来源。结果表明,中国近海大气气溶胶中有机胺的种类主要是二甲胺(DMA)和三甲胺(TMA),在2013年3月南海航次中这两种有机胺的平均浓度均是2.3nmol/m3,2013年6月黄渤海航次采集的大气气溶胶中DMA的浓度比南海大气中高,而TMA稍低,平均浓度分别为3.2nmol/m3和2.0nmol/m3;5月、8月以及10月东海航次中TMA的浓度较南海以及黄渤海航次均有所降低,平均浓度分别为0.3nmol/m3、1.7nmol/m3、0.3nmol/m3, DMA在5月以及8月航次中的平均浓度水平较南海与黄渤海差距不大,分别为2.4nmol/m3和2.8nmol/m3,而10月东海航次中DMA的浓度较低,为1.8nmol/m3。通过分析有机胺的粒径分布发现,在五个航次中,3-4月南海、6-7月黄渤海和8月东海所采集的气溶胶样品中DMA和TMA均主要分布在粒径小于2.1μm(PM2.1)的细颗粒上,DMA和TMA在PM2.1中的浓度占PM11(粒径小于11μm的颗粒物)中有机胺总浓度的比例达到70%-85%左右。分析5月和10月东海大气气溶胶中DMA和TMA的粒径分布则发现,DMA和TMA的分布规律并没有南海、黄渤海以及8月东海中所观测到的DMA和TMA分布规律好,但是总体上5月和10月东海气溶胶中DMA和TMA在PM2.1中的浓度也达到了PM11中有机胺浓度的50%左右。分析2013年3月南海、6月黄渤海以及8月东海三个航次中DMA和TMA的数据发现,DMA和TMA之间存在非常好的相关关系,R2值分别是0.80、0.86、0.89,表明它们有相同的来源；通过比较有机胺与典型的陆源污染特征离子NH4+和SO42-的浓度分布发现,有机胺的浓度变化趋势与NH4+、SO42的浓度变化不一致,说明陆源对海洋大气中有机胺的贡献很小,同时通过比较8月东海航次中有机胺的浓度和叶绿素a、异养细菌生物量的空间分布发现,总体上呈现较好的相关性,说明海洋生物排放可能是大气中有机胺的主要来源。此外,DMA和TMA在细粒子上的峰值分布与典型的二次离子NH4+和SO42-分布非常相似,NH4+和SO42-在2013年3月南海、6月黄渤海以及8月东海航次中在PM2.1细颗粒上的浓度占总浓度的65%～90%,同时这三个航次PM2.1中DMA、TMA的浓度也能达到总颗粒物中有机胺浓度的70%～85%左右；5月和10月东海航次采集的大气气溶胶中有机胺的浓度较其他三个航次中有机胺的浓度低,在PM2.1中的浓度约占总浓度的一半左右,NH4+和SO42-在PM2.1的浓度占总浓度的比例约为70%。DMA、TMA与NH4+、SO42在粒径分布上这种较好的一致性,说明中国近海大气气溶胶中有机胺主要是通过气-粒转化生成的。最后通过有机胺与NH4+的比值发现,DMA、TMA与NH4+的比值在粒径小于0.43μm的细粒子上较大,且DMA较TMA可能对中和酸的贡献更大,如在10月东海的航次中DMA与NH4+的比值达到了0.14,说明在一定的情况下有机胺在颗粒物的酸碱平衡中扮演着一定的角色。
[Abstract]:Using 57 sets of Anderson particle size aerosol samples collected from the South China Sea, the East China Sea, the East China Sea in May, the East China Sea in the East China Sea, the East China Sea in the East China Sea and the East China Sea in August, and the East China Sea in October, the concentration of organic amines is analyzed. The types, concentration distribution, particle size distribution and main sources of the atmospheric aerosols in China's offshore atmosphere are discussed. The results show that the Anderson is the main source of the organic amines. The main types of organic amines in atmospheric aerosols are two methylamine (DMA) and trimethylamine (TMA). The average concentration of these two kinds of organic amines in the March 2013 sea voyage of the South China Sea is higher than that of the South China Sea atmosphere in the atmospheric aerosols collected by the Yellow Bohai voyage in June 2.3nmol/m32013, and the TMA is slightly lower, the average concentration is 3.2nmol/m3 and 2.0nmol/m, respectively. 3, the concentration of TMA in May, August and October is lower than that of the South China Sea and Huang Bo sea voyage, the average concentration is 0.3nmol/m3,1.7nmol/m3,0.3nmol/m3, the average concentration of DMA in May and August is less than that of the South China Sea and the Yellow Bohai, 2.4nmol/m3 and 2.8nmol/m3 respectively, and the DMA concentration in the east sea voyage in October. By analyzing the particle size distribution of organic amines, it is found that in the five voyage, the DMA and TMA of the aerosol samples collected in the South China Sea, the Yellow Bohai and the East China Sea in the 3-4 month of the five voyages are mainly distributed on the fine particles with a particle size less than 2.1 m (PM2.1), and the concentration of DMA and TMA in PM2.1 is in the particles with a particle size less than 11 micron m. The distribution of DMA and TMA in the atmospheric aerosols in the East China Sea in May and October shows that the distribution of DMA and TMA has not been found in the South China Sea, the Yellow Bohai and the East China Sea in August, and the distribution of DMA and TMA is good, but the overall concentration of DMA and TMA in the Eastern Sea gas sol in May and October in May and October is concentrated in PM2.1, but the distribution of the particle size distribution of the atmospheric aerosols in the East China Sea in May and October The degree also reached about 50% of the concentration of organic amine in PM 11. Analysis of the data of DMA and TMA in the March 2013 South China Sea, yellow Bohai in June and the three voyages in the East China Sea in August found that there was a very good correlation between DMA and TMA, and R2 values were 0.80,0.86,0.89, indicating that they had the same source; by comparing organic amines to typical land source pollution. The concentration distribution of NH4+ and SO42- showed that the change trend of the concentration of organic amine was not consistent with the concentration of NH4+ and SO42, indicating that the contribution of Lu source to the organic amines in the ocean atmosphere was small. At the same time, by comparing the concentration of organic amines and chlorophyll a in the eastern sea aviation in August, the spatial distribution of the biomass of the heterotrophic bacteria was found to be better in general. The correlation shows that marine emissions may be the main source of organic amines in the atmosphere. In addition, the peak distribution of DMA and TMA on fine particles is very similar to the typical two ion NH4+ and SO42- distribution. The concentration of NH4+ and SO42- in the South China Sea in March 2013, the June yellow Bohai and the eastern sea navigation in August, account for 65% of the total concentration. To 90%, at the same time, the concentration of DMA and TMA in the three voyage PM2.1 can also reach about 70% ~ 85% of the concentration of organic amines in the total particles; the concentration of organic amines in the atmospheric aerosols collected in the East China Sea in May and October is lower than the concentration of organic amines in the other three voyages, and the concentration in PM2.1 is about half of the total concentration, and NH4+ and SO42- are in PM2 The ratio of the concentration of.1 to the total concentration is about 70%.DMA, TMA and NH4+, and the consistency of SO42 in the particle size distribution shows that the organic amines in the atmospheric aerosols in China are mainly generated by the gas particle transformation. Finally, the ratio of DMA and TMA to NH4+ is found to be larger on the fine particles with a particle size less than 0.43 u m through the ratio of organic amines to NH4+. And DMA may contribute more to neutralizing acid than TMA, for example, the ratio of DMA to NH4+ in the voyage of the East China Sea in October is 0.14, indicating that in certain circumstances organic amines play a role in the acid and alkali balance of particles.

【学位授予单位】：中国海洋大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X513

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