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1、环 境 地 球 化 学 1 Emissions of Parent, Nitro, and Oxygenated Polycyclic Aromatic Hydrocarbons from Residential Wood Combustion in Rural China 中国农村地区室内燃烧产生的母体、 硝化和含氧的多中国农村地区室内燃烧产生的母体、 硝化和含氧的多环芳烃排放物环芳烃排放物 学生姓名：XXX 班号：XXXX 学号：XXXXXXXX 20XX 年 XX 月 XX 日 环 境 地 球 化 学 2 ABSTRACT Residential wood combustion is o
2、ne of the important sources of air pollution in developing countries. Among the pollutants emitted, parent polycyclic aromatic hydrocarbons (pPAHs) and their derivatives, including nitrated and oxygenated PAHs (nPAHs and oPAHs), are of concern because of their mutagenic and carcinogenic effects.In o
3、rder to evaluate their impacts on regional air quality and human health, emission inventories, based on realistic emission factors (EFs), are needed. In this study, the EFs of 28 pPAHs (EFPAH28), 9 nPAHs (EFPAHn9), and 4 oPAHs (EFPAHo4) were measured for residential combustion of 27 wood fuels in ru
4、ral China.The measured EFPAH28,EFPAHn9, and EFPAHo4 for brushwood were 86.7 67.6, 3.22 1.95 102, and5.56 4.32 mg/kg, which were significantly higher than 12.7 7.0, 8.27 5.51 103, and 1.19 1.87 mg/kg for fuel wood combustion (p 0.05) and 5 times higher than12.1 6.7 mg / kg for fuel wood (p 0.05） ，并且
5、5 倍高 于乔木的 12.16.7mg/kg（p 0.05). pPAHs, oPAHs, and nPAHs EFs were all significantly positively correlated (p 0.05） 。 pPAHs，oPAHs 和 nPAHs 的 EFs 与同时 测量的 EF PM有显著的正相关关系 （p 0.05). Ambient pPAHs, nPAHs, and oPAHs concentrations in indoor and outdoor air in a rural household burning crop residue and wood f
6、or cooking were measured by Ding et al., 4 In comparison to this study, RN and RO ratios in ambient air were significant higher thanin emissions from wood combustion (p 0.05, SI Table S8). Although these ratios may be useful for identifying emissions from these different combustion sources, more fie
7、ld data is needed before it can be broadly applied in source apportionment. Gas-Particle Partition of pPAHs, nPAHs, and oPAHs. 0.7920.237 和 6.567.5410-2，在乔木和 灌木燃烧中的比例没有明显的差异 （p0.05） 。 Ding et al.在一个农村家庭里测量了用 农作物残留物和乔木烧火做饭的 pPAHs、 nPAHs和oPAHs在室内和室外周围空气中的 的浓度。与本次研究形成对比，周围空气的 RN和 RO的含量比例明显高于乔木燃烧的排 放量（p
8、0.05） ，特别是在夏季中的 RN。例 如， 周围空气中 1N-NAP/NAP 的含量比例在 冬季和夏季中分别为 1.1710-2和 2.8910-1， 并且两者在周围空气中的含量均 明显高于在研究中从乔木初级燃烧中测得 的 7.88 10-4的含量比例。 这表明,nPAHs 是 在直接燃烧排放后的光化学反应中形成的。 木材燃烧时产生了比农作物残余物和 煤燃烧显著更高的 9FO/FLO 含量比例，然 而农作物残余物燃烧产生较高的 ATQ /ANT 与 BaAQ /BaA 和较低的 9FO/FLO。煤炭燃 烧产生最低的 RO（SI 图 S4） 。在 RN和 RO上 的这些差异可能是用于区分室内
9、三种类型 固体燃料排放的有用方法。 。先前的研究发 现，RO与煤炭燃烧产生的 EF pPAHs呈明显的 正相关，与农作物残留物燃烧产生的的 EF pPAHs呈明显的负相关。然而，在此次乔 木燃烧研究中我们并没有发现类似的关系 （p0.05，SI 表 S8） 。虽然这些比例可用于 识别这些不同的燃烧源排放量， 然而需要更 多的数据， 然后才可以广泛地应用于来源解 析。 气体粒子分区的 pPAHs，nPAHs，oPAHs 环 境 地 球 化 学 19 Figure 6. Relationship between Kp of various PAHs and their molecular weig
10、ht (A) and dependence of Kp on logPL0 (B) and KOA (C). Kp, PL0, and KOA are all log transformed. 图 6.各种 PAHs 的 Kp与它们的分子质量之间的关系（A） 、Kp与 logPLO的关系（B） 、Kp与的 KOA关系。Kp、PLO和 KOA都为对数值。 pPAHs and their derivatives are emitted from combustion sources in the gaseous and / or particulate phase depending on the
11、ir molecular weight and vapor pressure. Gas-particle partitioning is usually described by the partition coefficient (KP), defined as Kp = F / (A PM), where F and A are the particle-bound and gaseous phase concentrations, and PM is the mass concentration of coemitted PM. Log-transformed KP values for
12、 the various compounds measured in this study were calculated and plotted against molecular weight in Figure 6A, showing an increasing tendency. As shown in SI Figure S5, Kp of most derivatives were significantly higher than (p 0.05). These results aresimilar to oPAHs emitted from crop residue and c
13、oal burning. In comparison with the corresponding pPAHs, the derivatives often have lower vapor pressures and are more likely to be present in the particulate phase. Gas-particle partitioning is thought to be controlled by the relative importance of absorption into organic matter and adsorption onto
14、 the particle surface.The two different pPAHs 及其衍生物是从燃烧源发出气态还 是颗粒相，取决于它们的分子量和蒸气压。 气体粒子分配通常分配系数描述（Kp） ，定 义为 Kp=F/（APM） ，其中 F 和 A 代表粒子 范围和气态浓度，PM 代表 PM 物质的质量 浓度。在图 6A 中测量标绘了本次研究中各 种化合物的Kp值的对数和它们的分子质量， 呈现出增加的趋势。正如在图 SI 图 S5 中显 示的， 大多数衍生物的Kp明显高于 （p0.05） 。这些结果与从农作物残余物和 煤炭燃烧产生的相应 pPAHs 结果类似。与 pPAHs 不同的是，这
15、些衍生物通常有较低的 蒸气压力，并且更可能是以颗粒相出现。 气体粒子分割被认为是由有机物吸收 和颗粒表面吸附的相对重要性控制的。 这两 种不同的 环 境 地 球 化 学 20 processes can be identified by plotting the KP values plot against the subcooled liquid vapor pressures (PL0), and the slope may indicate adsorption (steeper than -1) or absorption (shallower than -0.6) governanc
16、e, respectively. In this study on calculated slope of KP against PL0 is-0.39 0.06, suggesting a dominance of absorption into particles (Figure 6B). This mechanism of sorption is confirmed by the positive correlation between KP and octanol-air partition coefficient (KOA) (r = 0.919, p 0.05) (Figure 6C).A similar result was reported for crop residue and coal
