Evolution of tropospheric ions observed by an ion mobility spectrometer with a drift tube
Evolution of tropospheric ions observed by an ion mobility spectrometer with a drift tube
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带漂移管的离子迁移谱仪观测对流层离子的演化
DOI：
10.1029/97jd01974
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发表时间：
1998
影响因子：
--
通讯作者：
T. Ogawa
中科院分区：
文献类型：
--
作者：
K. Nagato;T. Ogawa
通过研究实验室空气中产生的离子迁移率谱随老化时间的变化，研究了对流层离子的演化。本文报道了一台带有漂移管的离子迁移谱仪，它能高分辨率地测量老化时间为0.03- 5S的离子的迁移谱。研究结果表明，对流层近地面离子迁移率谱随年龄的变化具有以下特征：正离子迁移率谱随年龄的变化显著，迁移率峰值从1.8 cm 2 V-1 s-1左右移动到1.0 cm 2 V-1 s-1。在正离子谱中，迁移率在2.0 ~ 1.0cm2V-1 s-1范围内有6个峰，并观察到正离子随着年龄的增加迁移率降低的趋势.有时在0.9 cm 2 V-1 s-1左右可分辨出另外四个峰，表明形成了重正离子（可能超过400 amu）。得到的负离子迁移率谱的特征在于在1.9和1.7 cm 2 V-1 s-1的两个突出的峰。两个峰的相对强度随离子年龄的变化而变化，迁移率为1.9cm2V-1 s-1的离子在约1 s后占优势。通过与迄今为止由Gerdien型抽吸冷凝器获得的自然离子谱的比较，可以预期负离子向具有较低迁移率的负离子的进一步转换。
The evolution of tropospheric ions has been studied by investigating the change in the mobility spectrum of ions generated in laboratory air as a function of aging time. An ion mobility spectrometer with a drift tube was constructed to get high-resolution measurements of mobility spectra of ions aged for about 0.03-5 S. Mobility spectra and their changes with ion age obtained in the present study showed the following features of tropospheric ion evolution near the ground: The positive ion mobility spectrum changes significantly with aging time, in which the peak mobility value shifts from 1.8 to about 1.0 cm 2 V -1 s -1 . Six peaks are usually distinguished in the mobility range between 2.0 and 1.0 cm 2 V -1 s -1 in the positive spectrum, and a tendency of positive ions to evolve to have lower mobilities with increasing ion age is observed. Four additional peaks are sometimes resolved at around 0.9 cm 2 V -1 s -1 , indicating formation of heavy positive ions (probably over 400 amu). The negative ion mobility spectrum obtained is characterized by two prominent peaks at 1.9 and 1.7 cm 2 V -1 s -1 . The relative intensity of the two peaks varies with ion age, and the ions with a mobility of 1.9 cm 2 V -1 s -1 dominate after about 1 s. Further conversions of the negative ions to those with lower mobilities can be expected from a comparison with the natural ion spectra obtained so far by the Gerdien type aspiration condenser.