基于稀释通道采样系统开展室内模拟燃烧实验,采用同位素稀释高分辨气相色谱-高分辨质谱法,分析了民用生物质和煤炭燃烧细颗粒物(PM_(2.5))中二噁英(PCDD/Fs)的排放特征并计算得到其排放因子.结合中国燃料消耗和人口密度数据,基于“自下...基于稀释通道采样系统开展室内模拟燃烧实验,采用同位素稀释高分辨气相色谱-高分辨质谱法,分析了民用生物质和煤炭燃烧细颗粒物(PM_(2.5))中二噁英(PCDD/Fs)的排放特征并计算得到其排放因子.结合中国燃料消耗和人口密度数据,基于“自下而上”的方法构建了中国民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的排放清单.研究结果表明:(1)民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的质量浓度在0.181~4.700 pg/m^(3)之间,国际毒性当量(I-TEQ)浓度范围为0.081~2.300 pg I-TEQ/m^(3),其中,2,3,7,8-四氯二苯并对二噁英(2,3,7,8-T4CDD)(P<0.01,R^(2)=0.90)这一单体同系物的质量浓度与总I-TEQ浓度存在强相关性,可作为民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs毒性的良好指标.(2)民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的质量浓度排放因子分别为(1.82±0.97) ng/kg和(4.09±2.76) ng/kg;I-TEQ浓度排放因子分别为(0.40±0.21) ng I-TEQ/kg和(0.53±0.24) ng I-TEQ/kg.(3)2021年,民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的排放量为90.0 g I-TEQ,从空间上看,PCDD/Fs的高排放区主要集中在东北和华东地区,排放高值大于8μg I-TEQ/km^(2).与前人研究相比,垃圾焚烧(22.56 g I-TEQ)和工业燃烧(208 g I-TEQ)PM_(2.5)中PCDD/Fs的排放量分别是民用生物质和煤炭燃烧排放量的0.2倍和1.5倍.这表明,民用生物质和煤炭燃烧是PM_(2.5)中PCDD/Fs排放不容忽视的重要来源.(4)民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs排放导致的个人吸入的平均健康风险分别为(9.5±7.2)×10^(-5)和(3.1±1.7)×10^(-5),分别是从事各类工业生产活动的职业工人((2.88±2.45)×10^(-5))的3.3倍和1.1倍.展开更多
This study analyzed 10 years of sounding data from Yongxing Island to characterize temperature,humidity,and wind profiles in the atmospheric boundary layer(ABL).Our key findings are as follows.(1)Relative humidity inv...This study analyzed 10 years of sounding data from Yongxing Island to characterize temperature,humidity,and wind profiles in the atmospheric boundary layer(ABL).Our key findings are as follows.(1)Relative humidity inversions(RIs)were the most frequent events(99.8%),followed by surface-based temperature inversions(SBIs,63%),elevated temperature inversions(EIs,50%),and low-level jets(LLJs,41%).(2)Higher near-surface temperature leads to a decrease in EI height,thickness,and intensity.(3)When EIs occurred,RIs were consistently observed beneath the base of the EIs.(4)The intensity of the RIs correlated negatively with surface humidity,whereas the intensity of the LLJs correlated positively with surface winds except in summer.(5)The boundary layer heights(BLHs)are best estimated using the potential temperature gradient method when EIs occur,otherwise,the Richardson number method is the best method.In contrast,the relative humidity and temperature gradient methods exhibit high dispersion or uncertainty.(6)The BLHs showed seasonal variability,peaking in winter(350–1450 m).These findings advance our understanding of ABL dynamics and BLH estimation over tropical islands.展开更多
文摘基于稀释通道采样系统开展室内模拟燃烧实验,采用同位素稀释高分辨气相色谱-高分辨质谱法,分析了民用生物质和煤炭燃烧细颗粒物(PM_(2.5))中二噁英(PCDD/Fs)的排放特征并计算得到其排放因子.结合中国燃料消耗和人口密度数据,基于“自下而上”的方法构建了中国民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的排放清单.研究结果表明:(1)民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的质量浓度在0.181~4.700 pg/m^(3)之间,国际毒性当量(I-TEQ)浓度范围为0.081~2.300 pg I-TEQ/m^(3),其中,2,3,7,8-四氯二苯并对二噁英(2,3,7,8-T4CDD)(P<0.01,R^(2)=0.90)这一单体同系物的质量浓度与总I-TEQ浓度存在强相关性,可作为民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs毒性的良好指标.(2)民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的质量浓度排放因子分别为(1.82±0.97) ng/kg和(4.09±2.76) ng/kg;I-TEQ浓度排放因子分别为(0.40±0.21) ng I-TEQ/kg和(0.53±0.24) ng I-TEQ/kg.(3)2021年,民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs的排放量为90.0 g I-TEQ,从空间上看,PCDD/Fs的高排放区主要集中在东北和华东地区,排放高值大于8μg I-TEQ/km^(2).与前人研究相比,垃圾焚烧(22.56 g I-TEQ)和工业燃烧(208 g I-TEQ)PM_(2.5)中PCDD/Fs的排放量分别是民用生物质和煤炭燃烧排放量的0.2倍和1.5倍.这表明,民用生物质和煤炭燃烧是PM_(2.5)中PCDD/Fs排放不容忽视的重要来源.(4)民用生物质和煤炭燃烧PM_(2.5)中PCDD/Fs排放导致的个人吸入的平均健康风险分别为(9.5±7.2)×10^(-5)和(3.1±1.7)×10^(-5),分别是从事各类工业生产活动的职业工人((2.88±2.45)×10^(-5))的3.3倍和1.1倍.
基金National Key Research and Development Program of China(2023YFC3008002)National Natural Science Foundation of China(U21A6001,42075059)Key Laboratory of Guangdong Province(2020B1212060025)。
文摘This study analyzed 10 years of sounding data from Yongxing Island to characterize temperature,humidity,and wind profiles in the atmospheric boundary layer(ABL).Our key findings are as follows.(1)Relative humidity inversions(RIs)were the most frequent events(99.8%),followed by surface-based temperature inversions(SBIs,63%),elevated temperature inversions(EIs,50%),and low-level jets(LLJs,41%).(2)Higher near-surface temperature leads to a decrease in EI height,thickness,and intensity.(3)When EIs occurred,RIs were consistently observed beneath the base of the EIs.(4)The intensity of the RIs correlated negatively with surface humidity,whereas the intensity of the LLJs correlated positively with surface winds except in summer.(5)The boundary layer heights(BLHs)are best estimated using the potential temperature gradient method when EIs occur,otherwise,the Richardson number method is the best method.In contrast,the relative humidity and temperature gradient methods exhibit high dispersion or uncertainty.(6)The BLHs showed seasonal variability,peaking in winter(350–1450 m).These findings advance our understanding of ABL dynamics and BLH estimation over tropical islands.
