Measurements of HNO 3 and N 2 O 5 using ion drift-chemical ionization mass spectrometry during the MILAGRO/MCMA-2006 campaign
Measurements of HNO 3 and N 2 O 5 using ion drift-chemical ionization mass spectrometry during the MILAGRO/MCMA-2006 campaign
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DOI：
10.5194/acp-8-6823-2008
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发表时间：
2008-11
影响因子：
6.3
通讯作者：
Jun Zheng;Renyi Zhang;Edward Charles Fortner;R. Volkamer;L. Molina;A. Aiken;J. Jimenez;K. Gaeggeler;J. Dommen;S. Dusanter;P. Stevens;X. Tie
中科院分区：
文献类型：
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作者：
Jun Zheng;Renyi Zhang;Edward Charles Fortner;R. Volkamer;L. Molina;A. Aiken;J. Jimenez;K. Gaeggeler;J. Dommen;S. Dusanter;P. Stevens;X. Tie
3月7日至31日在墨西哥城部署了一台离子漂移化学电离质谱仪（ID-CIMS），在墨西哥城大都会区(MCMA)-2006现场活动中测量气相硝酸（HNO3）和五氧化二氮（N2O5）。观察点位于墨西哥城市区北部的墨西哥彼得奥莱奥研究所，该地区主要排放来自住宅、车辆和工业的污染物。白天夜间和清晨，HNO3浓度低于200万亿分之一（ppt）。HNO3浓度从中部标准时间上午9时左右开始稳步上升，在下午早些时候达到峰值0.5 ~ 3 ppb，随后在下午5时左右急剧下降至峰值的一半以下。ID-CIMS与离子色谱仪/质谱计（ICMS）的相互比较表明，两者的HNO3测量结果吻合较好（r2 =0.75）。HNO3的混合比例与亚微米级气溶胶硝酸盐呈负相关，表明气粒分配过程是决定气体HNO3浓度的主要因素。不可逆损失
An ion drift-chemical ionization mass spectrome- ter (ID-CIMS) was deployed in Mexico City between 7 and 31 March to measure gas-phase nitric acid (HNO3) and dini- trogen pentoxide (N2O5) during the Mexico City Metropoli- tan Area (MCMA)-2006 field campaign. The observation site was located at the Instituto Mexicano del Petr ´ oleo in the northern part of Mexico City urban area with major emis- sions of pollutants from residential, vehicular and industrial sources. Diurnally, HNO3 was less than 200 parts per trillion (ppt) during the night and early morning. The concentration of HNO3 increased steadily from around 09:00 a.m. central standard time (CST), reached a peak value of 0.5 to 3 parts per billion (ppb) in the early afternoon, and then declined sharply to less than half of the peak value near 05:00 p.m. CST. An inter-comparison between the ID-CIMS and an ion chromatograph/mass spectrometer (ICMS) showed a good agreement between the two HNO3 measurements (R 2 =0.75). The HNO3 mixing ratio was found to anti-correlate with submicron-sized aerosol nitrate, suggesting that the gas- particle partitioning process was a major factor in determin- ing the gaseous HNO3 concentration. Losses by irreversible